184 results
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2. A comparative and comprehensive study on robust silver-immobilized chitosan/carboxy methyl chitosan macromolecules for elimination of dyes.
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Wang, Song, Rahman, Suhaib, Nawaz, Arif, Khan, Fatima, Atif, Muhammad, Khan, Adnan, Ali, Nisar, Yang, Yong, and Zhang, Shizhong
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RHODAMINE B , *MACROMOLECULES , *RESPONSE surfaces (Statistics) , *DYES & dyeing , *PERMUTATION groups , *FILTER paper , *CHITOSAN ,CATALYSTS recycling - Abstract
[Display omitted] • Recyclable silver immobilized chitosan/carboxy methyl chitosan macromolecules as visible light-responsive photocatalyst. • Structural tailoring morphological studies was scrutinized using advanced techniques. • Highly efficient photocatalytic degradation of methyl orange (MO) and rhodamine B (RB) dyes from wastewater. • Optimization of degradation using response surface methodology (RSM). This study explores the potential of modified chitosan (CH) resulting from carboxy methyl (CM) group substitution in the chitosan skeleton, producing carboxy methyl chitosan (CMCH). Silver (Ag) was loaded to chitosan and modified chitosan (carboxy methyl substituted chitosan) supported on cellulose filter paper (FP) to tailor organic–inorganic macromolecule composites "Ag-Chi/CFP and Ag-CMCH/CFP" further applied as substantial composite for the reductive removal of methyl orange (MO) and rhodamine B (RB) dyes from wastewater. The synthesized catalyst was characterized via FTIR, 1H NMR, XRD, and SEM analysis. The degree of substitution was also measured, which was approximately 0.85. The reductive elimination efficiency of Ag-CMCH/CFP and Ag-Chi/CFP for MO dye was 95.31% and 88.85 %. In comparison, the elimination of RB was 98.28 and 94.04 %, respectively, in 16 min time, 0.6 mM Ag concentration, 40 mg/L, dye concentration and 0.3 M NaBH 4 concentration. The synthesized catalysts were recycled three times. The degradation of MO and RB dyes using Ag-CMCH/CFP and Ag-Chi/CFP catalysts can be described by the first-order kinetic model. The determination coefficients (R2) and rate constants (k) values for MO degradation were found to be 0.9934 and 0.1736 s−1 for Ag-CMCH/CFP, and 0.9242 and 0.1001 s−1 for Ag-Chi/CFP, respectively. Similarly, for RB degradation, the R2 values were 0.9866 for Ag-CMCH/CFP and 0.9803 for Ag-Chi/CFP, with corresponding k values of 0.219 s−1 and 0.1548 s−1, respectively. The degradation process was optimized using response surface methodology (RSM) to determine the optimal conditions for maximum dye removal efficiency. The RSM models were statistically significant, as validated by ANOVA and correlation coefficient values. The F values of MO and RB models are significant as they have 2450.15 and 21999.37, respectively. The P value for both was <0.0001. [ABSTRACT FROM AUTHOR]
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- 2024
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3. Chromo-fluorogenic detection of Sarin, Tabun, and mustard gas mimics triggering the ring-opening reaction in a spirolactam-based probe.
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Ahamed, Sabbir, Tohora, Najmin, Sahoo, Rajkumar, Mahato, Manas, Sultana, Tuhina, Maiti, Arpita, Ghanta, Susanta, and Kumar Das, Sudhir
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MUSTARD gas , *NERVE gases , *TABUN , *PINK , *RING-opening reactions , *RHODAMINES - Abstract
A dual-mode chromo-fluorogenic probe BASO has been introduced that can selectively recognize sarin, tabun, and mustard gas mimics diethylchlorophosphate (DCP), diethylcyanophosphonate (DCNP), and 2-chloroethyl ethyl sulfide (2CEES) in a 1:1 water–dimethyl sulfoxide (DMSO) mixture while native one was non-fluorescent. The opening of the spirolactam ring due to the addition of DCP, DCNP, and 2CEES shows a noticeable pink colorimetric and pink color fluorometric change, which is readily detectable by the naked eye in the µM range in neutral medium. [Display omitted] • A dual-mode chromo-fluorogenic probe BASO has been introduced. • BASO can selectively recognize various nerve agents' and mustard gas mimics. • The opening of the spirolactam ring by the various nerve agents' and mustard gas mimics shows a pink colorimetric and fluorometric change, • BASO could detect various nerve agents' and mustard gas mimics in the µM range in the neutral medium by the naked eye. • BASO has been employed for detecting the vapor phase and soil sample analysis as a practical applicability. Nerve agents are becoming serious issues for the healthy and sustainable environment in modern civilization. Strategically, we have designed and introduced a Schiff base triggered dual chromo-fluorogenic probe BASO via condensation reaction between rhodamine B hydrazide and 3-formyl chromone, which can selectively recognize different toxic target analytes helping a reference to a healthy and sustainable environment. The BASO probe displays enhanced pink photoluminescence extraordinarily due to the introduction of sarin, tabun, and mustard gas mimics diethylchlorophosphate (DCP), diethylcyanophosphonate (DCNP), and 2-chloroethyl ethyl sulfide (2CEES), in a 1:1 water–dimethyl sulfoxide (DMSO) mixture while native one was non-fluorescent. The opening of the spirolactam ring owing to the addition of DCP, DCNP, and 2CEES shows a noticeable pink colorimetric and pink color fluorometric change, which is readily detectable by the naked eye in the µM range in neutral medium and found to be better than numerous available chemosensor (Table S1). We have also fabricated simple paper strip-based test kits as portable and displayable handy photonic tools for on-site detection without any expensive instrumental techniques. The probe BASO has also been employed for detecting the vapor phase and soil sample analysis as a practical applicability. The simple, rapid detection techniques make our probe unique and have significant utility for the recognition of DCP, DCNP, and vesicant or blistering agents mimicking 2CEES. [ABSTRACT FROM AUTHOR]
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- 2024
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4. Evaluation of the interaction between new trypanocide 1,2,4-triazolo-3-thiones with human serum albumin
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Rio, Gabriel F., Castro, Larissa Henriques E., Souza, Gabriela S.R., Augusto Chaves, Otávio, Edilson Freire de Lima, Marco, Cesarin-Sobrinho, Darí, and Sant’Anna, Carlos Mauricio R.
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- 2024
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5. Microscopic mechanism of enhancing shale oil recovery through CO2 flooding- insights from molecular dynamics simulations.
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Liu, Feng, Gao, Xiaoquan, Du, Jia, Lin, Liming, Hou, Dali, Luo, Jin, and Zhao, Jinsheng
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• Shale oil reservoirs have micro-nano pores and complex fluid occurrence characteristics. They are also rich in organic matter. When shale oil is adsorbed by organic carbon, it exists in both adsorbed and dissolved states. When the adsorption capacity of organic carbon reaches saturation, shale oil exists in the free state. • Molecular dynamics simulation studies have shown that the micro mechanisms of enhanced shale oil recovery through CO 2 flooding mainly include crude oil swelling, crude oil viscosity reduction, CO 2 diffusion, CO 2 extraction, CO 2 crude oil mixing, and adsorption and competitive adsorption, among others. • Molecular dynamics simulation of enhanced shale oil recovery through CO 2 flooding will primarily focus on CO 2 composite oil recovery, constructing composite mineral models, enhancing adsorption and dissolved shale oil recovery, and integrating with quantum mechanics research methods. Shale oil reserves are abundant worldwide and are a primary focus for future oil and gas development. Shale reservoirs are dense, highly heterogeneous, and have a low oil recovery degree. CO 2 flooding can achieve the efficient development of shale oil, but the development of micro- and nano-pores in shale oil reservoirs and the complexity of fluid occurrence make it difficult to analyze the micro-mechanisms governing the enhanced recovery of shale oil through macroscopic CO 2 flooding by conventional methods. This seriously limits the widespread application of CO 2 flooding in shale oil development. Molecular dynamics offers a microscopic perspective to analyze the interaction between CO 2 molecules and crude oil molecules in various states of occurrence, including their interaction with shale pore walls. This approach has become a crucial method for studying reservoir development. In this paper, first, the molecular dynamics simulation methods are summarized, including details on basic principles, force fields, ensemble theory, boundary conditions, simulation process, and molecular simulation software. Second, the characteristics of shale oil reservoirs are elucidated from the perspectives of shale reservoir properties, kerogen type, and occurrence status. The micro-mechanisms (swelling, diffusion, viscosity reduction, extraction, mixing, adsorption, and competitive adsorption) of the displacement of shale oil through CO 2 flooding are analyzed in detail, and the main factors (temperature, pressure, crude oil composition, CO 2 injection amount, etc.) affecting the mechanism of shale oil displacement through CO 2 flooding are summarized. Finally, this paper elucidates the current challenges in molecular simulation technology regarding the micro-mechanisms of CO 2 -enhanced oil recovery. It also discusses the potential applications and future development directions for CO 2 -enhanced shale oil recovery. Regarding CO 2 shale oil recovery, important future directions for molecular simulation include CO 2 composite oil recovery research, constructing composite mineral models, enhancing adsorption and dissolved shale oil recovery, and integrating quantum mechanics research methods. Molecular dynamics can accurately simulate the micro-displacement process of CO 2 in shale pores, build a bridge between macro- and micro-displacement dynamics, and provide guidance for the widespread application of CO 2 -enhanced shale oil recovery. This study provides a reference for the development and application of molecular simulation technology in unconventional oil and gas development. [ABSTRACT FROM AUTHOR]
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- 2024
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6. Molecular dynamics study on hydration characteristics of expansive clay minerals by temperature and inorganic salts.
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Zhou, Runnan, Zhang, Dong, Cheng, Hao, Jin, Tong, Ye, Peng, and Wei, Jianguang
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MOLECULAR dynamics , *CLAY minerals , *SALINE waters , *PETROLEUM , *HYDRATION , *KAOLINITE - Abstract
• Four different types of rock and mineral including Na-montmorillonite, quartz, kaolinite, calcite is selected in this paper to conduct the simulation. • Molecular dynamics method was used to simulate different temperature conditions as well as different inorganic salts added. • The mechanism of temperature and inorganic salts inhibiting water molecules was explained from a microscopic perspective. • External conditions will make the peak value of the first hydration layer formed by water molecules adsorbed on the rock wall change and he first hydration layer has a stable structure. Most strata rock minerals have hydrophilic characteristics and the mineral surface is negatively charged. It can adsorb water molecules to form hydration layers on the mineral surface. The existence of hydration layer will reduce the effective pore diameter of rock pore microchannel. Thus, the development efficiency of crude oil is affected. Hydration layer compared to free water, water molecules are arranged in a highly ordered manner, with higher density and more stable toughness. Therefore, it is very important to study the structure of hydration layer adsorbed on rock wall and its influencing factors. Four different rock and mineral types are selected in this paper: Na-montmorillonite, quartz, kaolinite, calcite. Molecular dynamics method was used to simulate different temperature conditions and adding different inorganic salts. Study the influence of temperature and inorganic salts on the hydration layer structure of rock wall. The simulation results show that the increase of temperature and the addition of inorganic salts of different components have a great influence on the adsorption of water molecules on the rock wall, and it changes the original structure of the hydration layer. The adsorption of water molecules on different rock surfaces and the effect of different rock walls on the adsorption of hydration layer are described in molecular form. This study explains the mechanism of temperature and inorganic salts inhibiting water molecules from a microscopic perspective. It is of great significance to study the physical properties of hydration layer. It provides a theoretical basis for the field well wall stability research. [ABSTRACT FROM AUTHOR]
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- 2024
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7. Recent advances of nanofiltration separation in pharmaceutical field from water to organic solution.
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Li, Cunyu, Ma, Yun, Tang, Shuwan, Xu, Yangyang, and Zhi, Xinglei
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MEMBRANE separation , *SEPARATION (Technology) , *PHARMACEUTICAL technology , *NANOFILTRATION , *POLLUTION - Abstract
• Review of application and challenge of nanofiltration in pharmaceutical wastewater. • Nanofiltration for organic pharmaceutical wastewater separation is limited. • A novel nanofiltration approach about molecular state and interfacial dispersion. • Compatibility can improve the application of nanofiltration. • Nanofiltration reduces environmental pollution and recycles wastewater. The pharmaceutical industry has grown rapidly, leading to significant improvements in drug quality and pharmaceutical technology. However, there is still an inevitable problem with the appropriate disposal of pharmaceutical wastewater. Pharmaceutical wastewater contains water, organic solvent, proteins, peptides, polyphenols, and other heat-sensitive ingredients. Because nanofiltration separation has technological advantages in room temperature, it is hard for alternative separation technologies to replace it. However, the separation model designed for aqueous solutions has significant disadvantages in organic solutions. To improve the applicability of the nanofiltration in the pharmaceutical industry, this paper reviewed the nanofiltration separation mechanism, application characteristics, and defects of active ingredients in organic solutions, combined with the actual states and interfacial mass transfer behaviors of components in complex solution systems based on the relationship among solute, solvent and nanofiltration membrane. The physicochemical characteristics of the nanofiltration membrane separation layer (effective separation pore size, membrane fouling, membrane material) and the solute's state change in conjunction with a transition in the solvent from water to organic in pharmaceutical wastewater. The differences in the diffusion behavior of solutes in various existing states at the nanofiltration membrane interface under the charge effect complete nanofiltration separation according to the effect of effective filtration pore size. It is found that models of nanofiltration separation are constructed based on solution separation parameters, the charge effect of the nanofiltration membrane, and effective separation pore size. It additionally suggested research strategies for the separation mechanism of active ingredients in organic solution: first, clarify the solute molecular state and nanofiltration membrane potential in organic solution; second, analyze the solute distribution curve in the interface layer with different existing states; third, calculate the effective filtration pore size of nanofiltration; fourth, according to the quantitative cutting model of the interface layer by effective filtration pore size, the nanofiltration separation mechanism was investigated. This paper provides a systematic review of the current state of application for nanofiltration technology in the pharmaceutical industry and suggests solutions appropriate for various solvent systems. These will help to increase the technology's applicability in the pharmaceutical industry, increase the effectiveness of using heat-sensitive ingredients, and lessen environmental pollution from organic wastewater. [ABSTRACT FROM AUTHOR]
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- 2024
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8. A review on modified red mud-based materials in removing organic dyes from wastewater:Application, mechanisms and perspectives.
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Fang, Wei, Zhou, Yue, Cheng, Mingqian, Zhang, Liping, Zhou, Tao, Cen, Qihong, Li, Bin, and Liu, Zewei
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ORGANIC dyes , *COLOR removal (Sewage purification) , *SOLID waste , *GRAVITATIONAL interactions , *METAL compounds , *DYE-sensitized solar cells , *CATALYTIC oxidation - Abstract
[Display omitted] • Modified red mud-based materials can remove dyes from wastewater. • Four removal mechanisms of dye from wastewater are reviewed. • Future research of modified RM-based materials for dye removal are pointed out. Red mud (RM) is a highly alkaline solid waste generated during alumina production and should be disposed of and recycled in an environmentally sound manner. Red mud is rich in metal compounds, making it a promising material for environmental remediation treatment. However, there are fewer papers on the removal of organic dyes from wastewater using modified red mud-based materials. Therefore, this paper provides a comprehensive review on the properties of dyes and reveals the adverse effects caused by dye wastewater pollutants. The application of modified red mud-based materials in dye wastewater are further reviewed. Meanwhile, the removal mechanism includes electrostatic gravitational interaction, hydrogen bonding, π-π bonding, and catalytic oxidation. In addition, this paper suggests that the activation methods for red mud materials should be optimized in future studies as well as develops red mud-based materials with absorbing many dyes. This paper aims to expand modified red mud-based materials application for removing organic pullents from wastewater and red mud utilization. [ABSTRACT FROM AUTHOR]
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- 2024
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9. A correction of the neglected tautomerism in the spectra prediction of o-methoxyaniline terminated monoazonaphthols: DFT and 15N NMR study.
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Antonov, Liudmil and Lyčka, Antonín
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TAUTOMERISM , *AZO dyes , *DENSITY functionals , *OPTICAL spectra , *ABSORPTION spectra , *POLAR effects (Chemistry) - Abstract
• It is shown that the tautomeric state plays a crucial role for the optical properties of azo dyes. • Currently there is no suitable DFT approach to predict the optical spectra of tautomeric azo dyes. • Do not neglect the tautomeric state. In a paper of Zhu and co-workers ("Study of the electronic effect and quantitative spectra predictions of o-methoxyanilineterminated monoazonaphthols: a combined experimental and DFT study" by Guoxun Zhu, Yan Lin, Wenxian Zhou, Huacan Song and Zhengquan Li, RSC Advances, 2023, 13 , 33736), the authors derived a protocol for the absorption spectra prediction is sulphonated azo naphthols assuming that they exist as single azo tautomers. However, as it is well known before and as shown by the available experimental data and the calculations, performed in this note, the studied dyes exist almost solely in hydrazone tautomeric form, which unavoidably affects the conclusions and linear relations made in the original paper. A detailed benchmarking on the spectra prediction, involving 39 density functionals (33 of them hybrid and 6 – pure) indicates that there is no a functional correctly predicting the absorption spectra of the tautomers in azo naphthols. [ABSTRACT FROM AUTHOR]
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- 2024
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10. Impact of micro-rotation on a double-diffusive radiative flow within a lid-driven enclosure fearuring Joule heating, porosity and Lorentz forces.
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Shahzad, Hasan, Li, Zhiyong, Tang, Tingting, and Kanwal, Marya
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RADIATIVE flow , *LORENTZ force , *HEAT radiation & absorption , *HEAT transfer , *PARTIAL differential equations , *ROTATIONAL motion , *FREE convection - Abstract
• The present paper explores the fluid dynamics, heat and mass transmission characteristics within hexagonal enclosure with square object. • The phenomenon encompasses the interplay of various physical mechanism, including micro-rotation of fluid particles, Joule heating, thermal radiation, porous materials, and magnetic field. • The governing nonlinear partial differential equations are transformed into non-dimensional form and then investigated numerically using continuous Galerkin finite element method. The pressure component of the momentum equation is removed by employing the Penalty parameter. • The validation of findings is ensured by establishing a consensus with previous studies. Flow, heat and mass distributions are depicted using streamlines, isotherms and isoconcnetrations. • Graphical representation of average Nusslet number and Sherwood number are also provided. It is anticipated to offer novel concept for enhancing the performance of cooling systems and optimizing the energy efficiency in diverse engineering applications. The present paper explores the fluid dynamics, heat and mass transmission characteristics within hexagonal enclosure with square object. The phenomenon encompasses the interplay of various physical mechanism, including micro-rotation of fluid particles, Joule heating, thermal radiation, porous materials, and magnetic field. The governing nonlinear partial differential equations are transformed into non-dimensional form and then investigated numerically using continuous Galerkin finite element method. The pressure component of the momentum equation is removed by employing the Penalty parameter. In order to achieve the consistent solution the value of Penalty parameter is set to 10 7. The analysis includes several physical parameters, such as Buoyancy ratio (−1–1), micropolar parameter (2–6), Joule heating parameter (0–5), Richardson number (0.5–5), thermal radiation parameter (0.1 – 0.5), Lewis number (0.1–5), Darcy number (0.001–0.1) and Hartmann number (0–50). Results reveal notable trends regarding the impact of key parameters on flow behavior and thermal-solutal transfer within cavity. Increasing Darcy numbers intensify fluid motion and subsequently augments thermal and solutal transfer. The flow regime shifts from shear fricition-dominated at low Richardson number to buoyancy-induced at high Richardson numbers. For concentration-dominant counter flow, a uniform distribution pattern emerges, while aiding flow leads to increased fluid velocity, temperature, and concentration. Additionally, the micropolar parameter influences flow velocity, with varying effects on heat and mass transfer rates depending on the Hartmann number. Mass distribution expands with increasing Lewis number, while temperature rises significantly due to variations in radiation and Joule heating parameters. These findings contribute to a deeper understanding of enclosed flow dynamics and have implications for the optimization of diverse engineering systems. [ABSTRACT FROM AUTHOR]
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- 2024
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11. Comments on "Fundamental properties and intermolecular interaction of triethylene glycol + ethylenediamine aqueous solution for CO2 capture".
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Motati, Saikiran and Acree, William E.
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CARBON sequestration , *INTERMOLECULAR interactions , *AQUEOUS solutions , *ETHYLENEDIAMINE , *MOLECULAR volume , *ETHYLENE glycol - Abstract
• Published Vex data in Table 5 and in Figure 2a are not the same. • Published Redlich-Kister equation does not back-calculated Vex values reported in Table 5. • Published Redlich-Kister equation does not back-calculated Vex values depicted in Figure 2a. • Inconsistencies also noted between tabulated and graphed values of Δ η and Δ G *E. A polemic is given regarding the volumetric properties that Wang and coworkers reported in their published paper. The tabulated excess molar volumes, Vex , reported by the authors are not the same values as graphically depicted in the paper. Our analysis of the experimental data indicated that the tabulated were likely calculated assuming a ternary system, while the graphically depicted values were likely calculated using a pseudo-binary system treatment. Similar inconsistences were noted between several of the tabulated and graphed viscometric properties in the published paper. [ABSTRACT FROM AUTHOR]
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- 2024
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12. Comparative study of nanoemulsion and micelle formed by surfactants containing benzene ring for spontaneous imbibition displacement.
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Yin, Junrong, Wu, Junwen, Wu, Nan, Liu, Weihua, Wang, Yibo, Xian, Chenggang, and Jia, Wenfeng
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ENHANCED oil recovery , *NONIONIC surfactants , *ANIONIC surfactants , *SURFACE active agents , *INTERFACIAL tension , *EMULSIONS - Abstract
• In this paper, a new formulation of nanoemulsion composed of two surfactants containing benzene rings was proposed, and compared with micelle for spontaneous imbibition displacement experiments. • In this paper, it was found that the nanoemulsion had good solubilization and enhanced oil recovery performance. • It is of great significance to select the best oil displacement agent and promote the application of oil displacement agent in oilfield. Nanoemulsion has a wide range of applications in oilfield chemistry due to its unique nanoscale size, excellent kinetic stability and high specific surface area. In this paper, a novel nanoemulsion oil flooding system was prepared using anionic surfactant sodium dodecyl benzene sulfonate (SDBS), the nonionic surfactant alkylphenol ethoxylates (OP-10), kerosene, n-butanol and deionized water. The particle size, Zeta potential, interfacial tension (IFT) and wettability properties were evaluated in the laboratory. The displacement performance of nanoemulsion was evaluated by the spontaneous imbibition experiment. Meanwhile, it compared with the same concentration of SDBS + OP-10 + n-butanol (SOB) system. The results showed that the particle size of the nanoemulsion was 70 ∼ 100 nm. When the concentration of nanoemulsion was 0.10 %, the oil–water IFT could reach 0.091 mN/m. The spontaneous imbibition oil recovery of the nanoemulsion (0.10 wt%) could reach 33.20 %, which was 23.02 % higher than that of SOB system. We also research the spontaneous imbibition displacement mechanism of nanoemulsion and micelle in low-permeability reservoirs. This paper will help to select the best oil displacement agent for the design of enhanced oil recovery (EOR) projects and promote the application of oil displacement agent in oilfield. [ABSTRACT FROM AUTHOR]
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- 2024
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13. Is there a relationship between conformational and transport properties of associative polymers in porous media?
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Chissonde, Salomao, Patel, Viralkumar, Sahib Azad, Madhar, and Trivedi, Japan J.
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POROUS materials , *FIELD-flow fractionation , *MOLECULAR weights , *POROUS polymers , *RHEOLOGY , *VISCOSITY - Abstract
• Associative polymers exhibit complex flow behavior in porous media. • Conventional shear rheology cannot decode the associative polymer's behavior in porous media. • Extensional rheology cannot decode the associative polymer's porous media behavior. • Retention complicates the transport behavior of associative polymers. • Conformational properties can decode the transport properties of associative polymer. This paper delves into the conformational and transport properties of three different associative polymers (C-319, P-329 and D-118) in porous media, focusing on the role of hydrophobicity at varying concentrations. In our latest paper it was reported that at 1000 parts per million (ppm), higher hydrophobic polymers (D-118) display a distinct increase in shear thickening but a decreased extensional viscosity compared to their less hydrophobic counterparts C-319 and P-329. This relationship inverts at 2000 ppm, where an increase in hydrophobicity is associated with a decrease in shear thickening, and extensional viscosity, suggesting extensional rheology of associative polymers could correlate with porous media behavior at higher concentrations but not at lower concentrations. Higher retention was found to be the reason for the higher resistance factor of higher hydrophobic polymers at 1000 ppm whereas at 2000 ppm they have less retention. Is there another phenomenon related to polymer physics that causes this contradiction, and plays a major role during the transport of associative polymeric flow in porous media? This paper aims to answer this question using the combination of extensional rheology and asymmetrical flow field-flow fractionation (AF4). The extensional viscosity of these systems at 1000 ppm are 90 Pa.s, 222 Pa.s and 201 Pa.s. At 2000 ppm, these values are 448 Pa.s, 344 Pa.s, and 196 Pa.s. The shape factor for D-118 was found to be between 0.41 (at 1000 ppm) and 0.20 (at 2000), an indication that the polymer chains are taking the conformation of random coils and spheres at 1000 and 2000 ppm respectively. For C-319 and P-329, respectively, these values are (0.51–0.57) and (0.40–0.49), an indication that they are even more random. It appears that the higher resistance factor shown by D-118 at 1000 ppm is due to the preserved randomness of the polymer chain and amplified Mw despite having the lower extensional viscosity. Contrarily at 2000 ppm, the shape factor was found to be 0.20, an indication that they are compacted. As the compacted polymer chain doesn't stretch, D-118 doesn't appears to get retained significantly at 2000 ppm. C-319 has more flexible chain than P-329 at both concentrations which is the reason why they have higher extensional viscosity and resistance factor. A novel contribution of this work is the elucidation of porous media transport properties of associative polymers, which are intricately tied to the randomness of polymer chains as well as their molecular weight and hydrophobic characteristics. The key novelty of this work is transport properties of the associative polymer in porous media are better delineated by a combination of AF4 and extensional rheology, and retention appears to be related to the randomness of the polymer chain. [ABSTRACT FROM AUTHOR]
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- 2024
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14. Proposed prototype for a quantitative biosensor for insulin detection using a liquid crystal.
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Satya, Athul and Bhattacharjee, Ayon
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BIOSENSORS , *LIQUID crystals , *INSULIN therapy , *INSULIN sensitivity , *BINDING energy , *MOLECULAR docking - Abstract
• Prototype for quantitative detection of Human insulin by 4-cyano-4-pentyl biphenyl (5CB) Liquid Crystals (LCs). • Concentration-dependent behaviour of the human insulin to LC was studied within the range of 25 μM and 500 μM under POM. • Molecular docking using AutoDock software to identify the minimum binding energy site of 5CB-LC on human insulin surface. • Ramachandran plot and Z-score values for stereochemical stability validation. • 5CB docking was conducted separately at four chains of human insulin structure, providing insights for enhancing biosensor accuracy. In this paper, we present a novel approach for label-free detection of human insulin using 5CB liquid crystal (LC). Monitoring insulin levels in the body is essential for treating diseases like diabetes, which are caused by insufficient production or inefficient use of insulin. Contemporary techniques of detection rely on glucose detection, and limited information is available on the direct detection of insulin. A simple method using a common room temperature LC 4-cyano-4-pentyl biphenyl (5CB) interacting with different concentrations of insulin, observed through a polarising optical microscope (POM), is reported in this paper. An analysis of observed textures revealed the detection of insulin as low as 25 μM concentration. The distinguishable features of the observed textures provide a scale for estimating insulin concentration. The effect of different pH and salt concentrations was studied in order to understand the optimal working condition of the proposed biosensor. Image J analysis demonstrated a positive correlation (R2 equal to 0.9553) between grey index (GI) values and human insulin concentrations. RGB analysis and interference studies confirmed the biosensor's specificity in insulin detection. To correlate the textures to the happenings at the molecular level, docking studies were carried out. In addition to this, properties such as aromaticity, H-bond, hydrophobicity, interpolated charges, ionizability and solvent accessible area (SAS) in the minimum energy binding sites of 5CB-LC and human insulin chains were measured to know more about the interaction properties. This novel strategy shows promise for improving insulin detection sensitivity and accuracy, ultimately leading to better diabetes management and healthcare outcomes. [ABSTRACT FROM AUTHOR]
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- 2024
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15. Molecular dynamics simulation of periodic flow containing contaminant in the regenerator.
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Zhu, Yifan, Chen, Xi, Zheng, Pu, and Lu, Yilin
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MOLECULAR dynamics , *PHASE transitions , *FLOW simulations , *REGENERATORS , *TRANSITION temperature - Abstract
[Display omitted] • Establish a NEMD model to investigate contaminated gases in the regenerator. • Focuses on N 2 to unveil its behavior patterns. • Observe N 2 cluster and adsorption to wire above the phase transition temperature. • Pressure and contaminant amount hardly affects the distribution. • Two predictions of the distribution of N 2 are proposed. The lifespan of regenerative refrigerators is predominantly influenced by contamination. This paper studies the interaction between N 2 and regenerator wire at a microscopic scale for the first time. A section of regenerator wire is simulated using molecular dynamics to investigate the impacts of temperature, charging pressure, and contamination amount. Based on the single-wire model, it indicates that N 2 initially forms clusters and then adheres to the wire surface when the temperature is below 80 K. Clusters decrease in size as the temperature rises from 80 K to 90 K. The quantity of N 2 attached to the wire decreases by 50% when the temperature reaches 130 K and decreases to 0 at 170 K. Charging pressure and contamination amount slightly affect adsorption. When a row of wires is aligned perpendicular to the flow, adsorption rates are fast and the adsorption process is completed in several cycles. At 50 K, the size of the largest cluster decreases by 80.6%, marking the greatest reduction. Based on this, the paper proposes that N 2 will mostly congeal within the regenerator between 90 K and 70 K while the refrigerator operates. This study establishes a theoretical foundation for further exploration of contamination-induced failure mechanisms. [ABSTRACT FROM AUTHOR]
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- 2024
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16. Exploring ultrasonic wave transmission in liquids and liquid mixtures: A comprehensive overview.
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Das, Niharika, Kumar Praharaj, Manoj, and Panda, Subhraraj
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ULTRASONIC waves , *THERMODYNAMICS , *LIQUID mixtures , *LIQUID density , *SPECIFIC gravity , *MEASUREMENT of viscosity - Abstract
• This review paper focuses on the ultrasonic studies to investigate the molecular structure and interactions in various liquid mixtures, including binary, ternary, and organic solutions. • The ultrasonic study has gained popularity due to its non-destructive testing (NDT) nature and finds applications in medical and scientific fields, agriculture, industries, and more. • The primary objective of this review is to explore the interactions between different liquid mixtures, employing different evaluation criteria. • Thermo properties, excess functions, and acoustic parameters are essential components of the examined research papers. An understanding of the molecular process can be gained by analyzing the molecule interaction using the knowledge of how thermodynamic parameters vary with composition and temperature. Reliable information about the chemical and physical characteristics of a broad range of liquid mixes is required by industry. This review examines multiple research papers investigating molecular interactions, focusing on the acoustic/ultrasonic technique. This technique employs ultrasonic waves to probe molecular interactions. Researchers utilized an ultrasonic interferometer to measure ultrasonic wave velocity, liquid density can be determined by using a specific gravity bottle, and employed the Ostwald viscometer for viscosity measurements. The velocity of ultrasonic waves, the density of a particular liquid combination, and viscosity can all be measured to analyze various acoustic and thermodynamic properties. Understanding the molecular interactions in each sample is greatly aided by this study. A detailed explanation of the many measured parameters has been provided. [ABSTRACT FROM AUTHOR]
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- 2024
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17. A systematic review on promising development of cost-effective, biodegradable, and environment friendly vegetable based nanofluids as a future resource for green transformer insulation oil.
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Siddique, Abubakar, Yaqoob, Muhammad, Aslam, Waseem, Zaffar, Faryal, Atiq, Shahid, and Usama Shahid, M.
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INSULATING oils , *TRANSFORMER insulation , *NANOFLUIDS , *LIQUID dielectrics , *VEGETABLE oils , *BASE oils - Abstract
• This comprehensive review paper explores the evolution of dielectric fluids for transformers, emphasizing environmentally friendly alternatives and advancements in nanofluids. The adoption of ester-based dielectric liquids, both synthetic and natural, is examined, highlighting their fire safety, biodegradability, and environmental sustainability. • Studying how nanofluids age is crucial to understand how well they perform in real and extended operating situations for transformers. Yet, because of stability concerns, the ageing process used for regular insulating oils can't be applied to nanofluids. • Enhancing the heat and electricity features of the liquid can bring about significant transformations in the design of transformers. Additionally, the mismatch between nanofluids and the current transformer materials necessitates the exploration of new materials for the secure and effective functioning of transformers. Investigating the necessary design adjustments for transformers filled with nanofluids represents another area that requires thorough examination. • In contrast to using just one kind of tiny particle and a basic fluid, nanofluids that involve multiple particles and a blend of base fluids employ various types of nanoparticles mixed in different proportions with the base oil. Each type of particle has the potential to boost various properties, both in the nanoparticles themselves and in the base oil. The contribution of this article is to update the reader on the latest developments of transformer insulating oils in ensuring the reliability of power systems. Commencing with the prevalent use of mineral oil (MO), our exploration extends to alternative solutions, including esters. The scrutiny of esters involves a particular emphasis on natural variants highlighting their potential as eco-friendly substitutes for conventional insulating oils. A significant aspect of this work entails the incorporation of different nanoparticles (NPs) into vegetable insulating oils, forming nanofluids, which emerge as a promising avenue for enhancing insulating properties. The paper systematically categorizes nanoparticles based on conductivity and thoroughly examines nanofluid synthesis methods. Stability assessment techniques, encompassing sedimentation capturing, zeta potential analysis, and spectral analysis, are discussed alongside strategies for stability enhancement, including surfactant addition, surface modification, ultrasonic agitation, and pH control. Environmental considerations, covering biodegradability, recyclability, and fire protection, are scrutinized for both mineral and vegetable oils. [ABSTRACT FROM AUTHOR]
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- 2024
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18. A Machine Learning approach for enhancing permittivity mixing rules of binary liquids with a Gaussian modification and a new interaction factor estimation.
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Monteagudo Honrubia, Miguel, Herraiz-Martínez, Francisco Javier, and Matanza Domingo, Javier
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MACHINE learning , *PERMITTIVITY , *DIELECTRIC resonators , *MOLECULAR volume , *GAUSSIAN function - Abstract
The microstructure and solvation mechanics of binary liquids are key for predicting mixture permittivity. However, since traditional mixing rules do not consider this complexity, they must be modified to address the mixture characteristics through an interaction factor (k i n t). This paper evaluates this parameter for several mixing rules, applying Support Vector Regressor models trained with glycerin-water reflective signals acquired with a Dielectric Resonator sensor. The regression error of these models indicates both the optimal interaction factor and the mixing rule that fits the most with experimental permittivity values. Kraszewski and Hashin-Shtrikman mixing rules achieved the best performance with an RMSE of around 1. In addition, this paper suggests that the interaction factor can be estimated through the molar volume and the dielectric contrast between liquids (k i n t = 2.67) without acquiring experimental data. Moreover, after analyzing the physical limitations of a linear modification formula, this paper proposes an alternative based on a Gaussian function that avoids unrealistic volume fractions. Both contributions enhance mixing rule accuracy and improve the flexibility to model mixture dielectric behavior. • Machine Learning models trained with a specific mixture data can validate any permittivity characterization from any mixture. • A novel estimation formula to calculate the interaction factor through the molar volume ratio and the dielectric contrast. • A Gaussian formula provides physically realistic volume fraction modifications to model the mixture dielectric behavior. • Multiparametric fraction volume modification enhances the fitting between mixing rule estimations and experimental values. [ABSTRACT FROM AUTHOR]
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- 2024
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19. Gold(III)-DNA interaction in aqueous solution.
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Akulinina, A.A., Roshchin, I.S., Konstantinov, L.E., Yarullin, D.N., Zavalishin, M.N., Kholodkov, I.V., and Gamov, G.A.
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STABILITY constants , *AQUEOUS solutions , *ATOMIC force microscopy , *GOLD , *COORDINATION compounds , *HYDRAZONES - Abstract
In aqueous solutions, gold(III) complexes with organic ligands in the presence of DNA can dissociate releasing metal ion. A degree of dissociation depends on the stability of gold(III) complexes with DNA and a small molecule. This paper reports on the stability constants of the complexes formed by chlorohydroxy complexes of gold(III) and DNA. [Display omitted] • Nature of gold(III) species interaction with DNA depends on C(Cl-). • Log K of gold(III) species binding with DNA are determined. • AFM confirms the gold(III)-DNA interaction. • Speciation diagram for the system of gold(III)-hydrazone-DNA is drawn. Gold(III) complexes resemble cisplatin and other similar platinum(II) complexes in structure and electron properties. Because of this similarity, the coordination compounds formed by gold(III) can find application in medicine. They are considered to bind with DNA, disrupting its normal replication. However, there are a few available papers devoted to the study of the interaction between tetrachloroaurate(III), which is used often for the synthesis of other gold(III) complexes, and DNA. The stability constants of gold(III) and DNA are also useful for studying the reactions between gold(III) complexes and DNA, as the dissociation of the metal complex is possible. Therefore, this paper describes the interactions between [AuCl 4 ]- and its hydrolyzed species and DNA in pure water and aqueous 0.1 M NaCl solution. Binding mode and binding constants are determined from the results of UV–Vis and circular dichroism titration, while the kinetic fluorescent measurements are used to study the ethidium bromide replacement. Atomic force microscopy is also used to show the influence of gold(III) species on DNA. The calculated equilibrium constants are used to calculate the speciation diagram for the solution containing chlorohydroxyaurate(III) species, hydrazone derived from pyridoxal 5′-phosphate, and DNA at different pH values. [ABSTRACT FROM AUTHOR]
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- 2024
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20. Flexible metallosalen complex for pyrophosphate sensing in biological milieu: Use disassembly strategy for signal amplification.
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Mondal, Sourav and Dey, Nilanjan
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FLUORESCEIN , *PYROPHOSPHATES , *COMPLEX compounds , *SIGNAL detection , *ELECTRONIC structure , *MOLECULAR structure , *WATER sampling - Abstract
[Display omitted] • Ppb-level, ratiometric detection of pyrophosphate: Signal amplification. • Pyrophosphate induced demetallation which led to disassembly of probe molecule. • Electronic influence of spacer unit: rigid vs flexible spacer. • Detection in diluted blood serum samples and inside living cells. • On-location rapid detection using low-cost, reusable paper strips. In the present work, we have designed and synthesized two dimeric fluorescein derivatives with flexible salen (1) or a rigid salophen (2) linker unit. The Fe(III) complexes of these compounds ([ 1.Fe]+ and [ 2.Fe]+) showed changes in solution color specifically upon addition of inorganic pyrophosphate (PPi) at pH 7.0 in PBS buffer. Along this, we also observe appearance of green fluorescence (turn-on) in the prescence of PPi. The mechanistic studies suggested PPi-induced demetallation process, which led to disassembly for molecular structure in the aqueous medium and release of highly fluorescent fluorescein aldehyde. The disassembly process was found to be dependent on electronic structure, rigidity of the linker unit, temperature, and local pH etc. The selectivity as well as sensitivity of [ 1.Fe]+ towards PPi was also found to be superior than that observed with [ 2.Fe]+. Since each disassembly process released two signalling unit (fluorescein), we could observe a huge increment in FL intensity even with small quantity of PPi (<10 µM). Finally, the sensory system was utilized for detection of PPi in diluted blood serum samples and inside living mammalian cells (HeLa, cervical cancer cells). Chemically-modified paper strips have been developed for the detection of PPi in water samples at outside laboratory conditions. [ABSTRACT FROM AUTHOR]
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- 2024
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21. Surface modification of superparamagnetic nanoparticles for enhanced oil recovery: A review.
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Che Mohamed Hussein, Siti Nurliyana, Jan, Badrul Mohamed, Khalil, Munawar, Amir, Zulhelmi, and Azizi, Azlinda
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ENHANCED oil recovery , *POROUS materials , *SURFACE charges , *NANOPARTICLES , *INTERFACIAL tension - Abstract
[Display omitted] • Superparamagnetic nanoparticles (SPNs), show great potential for enhanced oil recovery (EOR) methods. • The synthesis methods for fabricating SPNs and the parameters affecting synthesis are discussed. • Various types of surface modifiers used in EOR and the parameters for successful surface modification are reviewed. • The mechanism involved in using surface modifiers to improve the performance of SPNs in EOR application are emphasized. • Further studies can explore the relationship between modified SPNs and other types of EOR applications. It is no secret that nanoparticles are promising material which have been used to improve the efficiency of enhanced oil recovery (EOR). Superparamagnetic nanoparticles (SPNs) are material often used in EOR due to their superior properties namely high surface-to-volume ratio, excellent superparamagnetic abilities, high thermal stability, and ease of fabrication. However, SPNs are known to be hydrophobically weak and prone to aggregation due to its magnetic nature and high surface charge. To minimize this issue, surface modification have been employed to reduce the agglomeration of SPN. This review paper discusses the development and performance of SPNs post surface modification from EOR perspective. Firstly, this paper details the synthesis methods of SPNs fabrication and the key parameters influencing their synthesis. The discussion also covers the types of surface modifiers and critical parameters in EOR applications. Furthermore, this review paper highlights the mechanisms involved in EOR application in which surface modifier was applied to improve the performance of the SPNs. Finally, this review includes discussion on modelling, simulation works and field trials. Based on the reviewed literature, it seems that surface modification of SPNs tends to exhibit excellent stability. This, in turn, leads to higher oil recovery rates of up to 73%. By varying the surface modifications of SPNs, promising results can be achieved such as a low contact angle of up to 14.7 degrees, indicating a strongly water-wet state; a mobility ratio of 0.86, which is less than 1 and signifies an adequate sweep efficiency; and a significant reduction in interfacial tension from 3.7mN/m to 0.84 mN/m, a reduction of 77%. To gain deeper insights into the potential of SPNs, further studies which involve modelling of interaction between the modified SNPs and porous media under reservoir condition should be initiated. [ABSTRACT FROM AUTHOR]
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- 2024
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22. The thickening mechanism of CO2 thickener poly (vinyl acetate -vinyl ether) (PVAEE): A molecular dynamics study.
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Du, Yingzhe, Liu, Shasha, and Yuan, Shiling
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VINYL ethers , *MOLECULAR dynamics , *VINYL acetate , *THICKENING agents , *DISTRIBUTION (Probability theory) , *ELECTRIC potential , *CARBON dioxide - Abstract
TOC The visocisty of CO 2 and the spatial distribution function of two oxygen containing groups on PVAEE. [Display omitted] • With the increasing of PVAEE, the viscosity of CO 2 also increases, indicating that the addition of PVAEE can improve the thickening efficiency. • PVAEE will gradually curl and aggregate under the effect of electrostatic potential energy, forming a certain network structure. • We also found that CO 2 molecules tend to be circularly distributed around the methyl (CH 3) groups on the VAc and VEE groups. • VDW potential interaction energy is the main driving force. This paper performed molecular dynamics simulation to calculate the effect of poly (vinyl acetate-vinyl ether) (PVAEE) on the viscosity of CO 2 and its thickening mechanism. The main conclusions are as follows: i) With the increasing of PVAEE, the viscosity of CO 2 also increases, indicating that the addition of PVAEE can improve the thickening efficiency. VDW potential interaction energy is the main driving force. ii) PVAEE will gradually curl and aggregate under the effect of electrostatic potential energy, forming a certain network structure. The curled PVAEE chains can increase the rigidity and viscosity of the system. iii) Through studying the properties of the Vinyl Acetate (VAc) and Vinyl Ether (VEE) groups under salt ions environment, we found that VAc groups on PVAEE can bind more CO 2 and increase viscosity significantly than VEE groups. iiii) Moreover, we also found that CO 2 molecules tend to be circularly distributed around the methyl (CH 3) groups on the VAc and VEE groups. While Ca2+ and Mg2+ ions tend to be distributed around O atoms of them. Based on the conclusions above, this paper can provide selection and assistance for the synthesis of better CO 2 thickeners. [ABSTRACT FROM AUTHOR]
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- 2024
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23. Efficient adsorption of butyl xanthate by imidazolium ionic liquid modified fumed silica.
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Zhao, Baoxun, Deng, Lijun, Wang, Yaming, Li, Guosheng, and Cao, Yijun
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ADSORPTION kinetics , *ADSORPTION (Chemistry) , *SILICA , *ADSORPTION isotherms , *POROUS silica , *IONIC liquids - Abstract
• Imidazolium ionic liquid was impregnated onto fumed silica at room temperature. • Ionic liquid could alter the charge characteristics of fumed silica and as active groups for adsorption. • IFS exhibited a high adsorption capacity along with a rapid adsorption rate. • IFS demonstrated excellent reusability. Butyl xanthate (BX) usually serve as an available collector in the sulfide mineral flotation. However, it will cause severe pollution and be harmful for living beings when discharged together with beneficiation wastewater. Adsorption, affected by sorbents structure to a great extent, is an effective strategy to treat BX-bearing wastewater. In this paper, ionic liquid-loaded fumed silica (IFS) generated by a simple process was acted as an adsorbent for removing BX from aqueous solution. The ratio of IL loaded onto silicon was about 40 %. The N elements existing in the structure of adsorbents suggested IL loaded onto silica surface successfully. The specific surface area of IFS was 65.25 m2/g, which was smaller than original material. And the total pore volume decreased from 36.75 to 15.22 cm3 g−1 after modification. Different from the virginal silica barely adsorbing BX, ionic liquid (IL) loaded silica had large uptake capacity up to 202.84 mg/g under the combined effect of functional groups modified in the silica particle and the porous structure of nanomaterial. The adsorption kinetics and isotherms are followed with the pseudo-second-order model and Langmuir model, respectively. And the functional groups, charge of adsorbent were analyzed to reveal approaching mechanism. This paper provides an alternative for xanthate and other organic contaminants treatment. [ABSTRACT FROM AUTHOR]
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- 2024
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24. Hansen solubility parameters sphere calculations and thermodynamic model fitting of two novel copper complexes supported by bis(imino)pyridine ligands.
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Zhang, Wenyue, Ma, Xiaoli, Yang, Cancan, Ni, Congjian, Pang, Ziyuan, Li, Xinyan, and Yang, Zhi
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THERMODYNAMICS , *SOLUBILITY , *PYRIDINE , *HEAT radiation & absorption , *LIGANDS (Chemistry) , *COPPER compounds , *METAL complexes - Abstract
• The solubility of four compounds was investigated. • The experimental solubility data were correlated by thermodynamic models. • The values of HSPs for metal complexes were predicted. • The optimal mixing ratios of the two metal complexes in the two mixed solvents were predicted. In this paper, two novel five-coordinated copper(II) metal complexes, [2,6-(ArN = CMe) 2 C 5 H 3 NCuCl 2 ] (Ar = 2-EtC 6 H 4 , L 1 CuCl 2 ; Ar = 4-EtC 6 H 4 , L 2 CuCl 2), bearing bulky 2,6-bis[1-(2-ethylphenylimino)ethyl]pyridine ligands L 1 (L 1 = 2,6-(ArN = CMe) 2 C 5 H 3 N, Ar = 2-EtC 6 H 4), 2,6-bis[1-(4-ethylphenylimino)ethyl]pyridine ligands L 2 (L 2 = 2,6-(ArN = CMe) 2 C 5 H 3 N, Ar = 4-EtC 6 H 4) have been synthesized and characterized, and the thermodynamic properties of these complexes are reported in a variety of mono-solvents. The copper(II) metal complexes based on bis(imino)pyridine are widely used in catalysis, photoelectric material, biopharmaceuticals and other fields. In this paper, the solubility of L 1 and L 2 in four solvents, the solubility of L 1 CuCl 2 in four solvents and the solubility of L 2 CuCl 2 in five solvents were studied by static analysis. The solubility of these compounds was investigated in a certain temperature range to provide data to support the selection of optimal solvents for organic reactions, coating and crystallization separations. Hansen solubility parameters (HSPs) were used to explain the dissolution behavior of solutes and were found to be consistent with experimentally measured results. Moreover, the values of HSPs for L 1 CuCl 2 and L 2 CuCl 2 lacking Cu data were simulated by the Hansen Solubility Parameters in Practice (HSPiP) software, which allowed the prediction of solvents with good dissolution behavior. The values of total solubility parameter of Hildebrand (δ) for L 1 CuCl 2 and L 2 CuCl 2 are 24.5 and 23.0, respectively. Besides, solubility properties of L 1 CuCl 2 and L 2 CuCl 2 in two solvent mixtures at different percentages were predicted. In addition, seven thermodynamic models were used to correlate the solubility data. For L 1 and L 2 , Polynomial models fit better with an average absolute relative deviation (ARD) less than 1 %; for L 1 CuCl 2 and L 2 CuCl 2 , Polynomial model fits best (ARD < 1 %). In addition, the enthalpy–entropy compensation relationship in the dissolution process was analyzed by calculating the thermodynamic parameters of the substances, and the results showed that the dissolution process of L 1 and L 2 was an enthalpy-driven heat absorption process. [ABSTRACT FROM AUTHOR]
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- 2024
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25. Comments on the calculation of thermodynamic adsorption equilibrium constant using the distribution coefficient in Journal of Molecular Liquids 380 (2023) 121725.
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Zhou, Xueyong, Zhang, Xiaoying, Hao, Jianchao, and Liu, Huifen
- Subjects
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THERMODYNAMIC equilibrium , *FERRIC oxide - Abstract
• The unit of distribution coefficient is the ratio of the mass of adsorbent to the volume of solution. • Confusion of adsorbate and adsorbent leads to miscalculation of the standard equilibrium constant. • The correct method for computing K o by distribution coefficient was provided here. This comment discussed the calculation of the standard equilibrium constant thermodynamic parameters about the paper published in Journal of Molecular Liquids 380 (2023) 121725. Recently, Khankhasaeva et al. (2023) published a high academic paper to reveal the adsorption kinetic and thermodynamic regularities of diclofenac (DCF) on Fe 2 O 3 -pillared montmorillonites (Fe-PMts). Although the author tries to convert the distribution coefficient (K d) to the standard equilibrium constant (K o), the calculation formula is incorrect due to the confusion of adsorbate and adsorbent. This creates dimension for K o obtained from Eq. (2). In this comment, the origin and background of this kind of error is analyzed and the method for correcting the error is presented. We hope this comment clarifies the essence of calculating the standard equilibrium constant by using the distribution coefficient, so others avoid the propagation of this kind of error. [ABSTRACT FROM AUTHOR]
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- 2024
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26. NADES systems comprising choline chloride and polyphenols: Physicochemical characterization, antioxidant and antimicrobial activities.
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Uka, Denis, Kukrić, Teodora, Krstonošić, Veljko, Jović, Branislav, Kordić, Branko, Pavlović, Ksenija, and Popović, Boris M.
- Abstract
[Display omitted] • Four out of ten systems could be diluted with water without affecting their stability, increasing their applicability. • The viscosity of the system decreases as the choline chloride content increases. • Selected systems showed antibacterial activity against Escherichia coli ATCC 25922 and Salmonella enterica ATCC 13076. Natural Deep Eutectic Solvents (NADES) represent a new group of green and environmentally friendly solvents that comply with all the principles of green chemistry. NADES are formed via hydrogen bonding by combining hydrogen bond donors (HBD) and hydrogen bond acceptors (HBA). In this paper, we presented ten NADES systems based on choline chloride and different polyphenols. The basic physicochemical and biological properties were evaluated (stability, density, viscosity, FTIR, ORAC, antibacterial activity). It was shown that all the systems had a high densities and high dynamic viscosities. The densities ranged from 1.096 – 1.221 mg/mL for ChCl – resveratrol and ChCl – rutin, respectfully. The dynamic viscosities ranged from 0.247–1.662 Pa S for ChCl – gallic acid and ChCl – chlorogenic acid, respectfully. The viscosity could be lowered by increasing the molar ratio of choline chloride. Four NADES systems, comprising catechin, rosmarinic acid, gallic acid and chlorogenic acid could be diluted with water without affecting the stability of those systems. This finding could increase the usability of those systems. The FT-IR analysis of the selected systems showed that the peaks are widened and slightly shifted, without formation of new peaks, which proves the formation of hydrogen bonds between the NADES constituents. All tested systems showed high ORAC value (426.94–874.96 Trolox eq/mL) and antibacterial activity (0.625–2.5 % NADES). [ABSTRACT FROM AUTHOR]
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- 2024
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27. Elucidation of the solution structure of macrocyclic paritaprevir and exploration of its antitumor potential through molecular docking.
- Author
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Zhang, Xiong, Li, Tong, Xu, Hongyu, Wang, Qi, Wu, Xiaodan, Yan, Rui, Jin, Yingxue, and Wang, Zhiqiang
- Abstract
[Display omitted] • The structure of paritaprevir in protic and aprotic solvents was investigated. • The weak noncovalent interactions within different conformations in liquid environments were analyzed. • The antitumor potential of paritaprevir was elucidated through molecular docking. Macrocyclic molecules have emerged as significant contenders in drug development and supramolecular chemistry. Paritaprevir is a 15-membered macrocycle approved for the treatment of chronic Hepatitis C virus infection. The structural flexibility inherent in paritaprevir enables the presentation of diverse conformational features in solutions, thereby influencing its binding pattern with proteins. In this paper, we investigated the structural characteristics of paritaprevir in protic solvents (methanol and trifluoroethanol) as well as an aprotic solvent (acetonitrile) by using experimental electronic circular dichroism spectra combined with density functional theory calculations. Our study reveals that paritaprevir can adopt different molecular conformations due to its flexible carbon chain and the solvent environment. Conformer B is particularly stable in polar solvents because of the planar hydrophobic interactions between the phenanthridine and methylpyrazine groups. Density functional theory calculations-assisted structural analyses further disclosed the weak noncovalent interactions within the stable conformations of paritaprevir. Molecular docking of paritaprevir on different cancer proteins showed that the macrocycle was highly selective against lymphoma, endometrial carcinoma, colorectal cancer, and breast cancer. This suggests that paritaprevir could potentially serve as a promising lead compound for drug design targeting these specific types of cancers. The comparison between the low energy conformation and pharmacophore conformation (docking conformation) indicates that conformer B is the primary pharmacophore conformation of paritaprevir, providing important macrocyclic structural characteristics for future macrocyclic drug development. [ABSTRACT FROM AUTHOR]
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- 2024
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28. Molecular simulation of understanding the structure and separation thermodynamics of BTX (Benzene, Toluene, Xylene) using amino acid based ionic liquids.
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Kumar, Manish and Sappidi, Praveenkumar
- Abstract
[Display omitted] • The amino acid based ionic liquid considering tetra butyl phosphonium and valine anion is considered for the separation of BTX. • ΔG solv of BTX in IL is favourable at 298 K when compared to n-heptane. • Log P values show favourable for the separation of benzene. The separation of aromatics and aliphatic from the hydrocarbon mixture stands a significant challenge. In this manuscript we present atomistic molecular dynamic simulations to understand the structure and separation thermodynamic properties of BTX (Benzene, toluene, xylene) from n-heptane using ionic liquids. Here we considered the amino acid derived ionic liquid considering the tetra butyl phosphonium as cation and valine anion at three different temperatures 298 K, 323 K and 348 K. We observe that IL show strong intermolecular structure with BEN (benzene) when compared to TOL (toluene) and XYL (p-xylene). Based on the solvation free energy (ΔG solv), transfer free energy (ΔG transfer) and partition coefficient (log P) analysis of BEN show favourable for the transfer from n-heptane to IL phase when compared to TOL and XYL. Overall results presented in this paper provide molecular level understanding of the design of amino acid-based IL for the separation BTX from the hydrocarbon mixture. [ABSTRACT FROM AUTHOR]
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- 2024
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29. Effects of imidazolium-based ionic liquids on the elasticity of DNA revealed by magnetic tweezers.
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Chen, Yun-Long and Zhang, Xing-Hua
- Abstract
[Display omitted] • DNA maintains the B-conformation after interacting with ILs ([bmim]Cl and [omim]Cl). • ILs induce unwinding and softening of DNA. • ILs binding to DNA surface reduce DNA torsional stiffness and twist-stretch coupling. • ILs reduce Na+ and water binding on DNA and take part in the solvation process of DNA. The functions of DNA are related to its mechanical properties, including elasticity and conformational transitions. Ionic liquids, known as green solvents, are used for DNA separation and as a solvent medium for long-term DNA storage. This paper elucidated DNA interaction mechanisms with two imidazolium-based ionic liquids: 1-butyl-3-methylimi-dazolium chloride ([bmim]Cl) and 1-octyl-3-methylimidazolium chloride ([omim]Cl), via magnetic tweezers, bulk techniques and molecular dynamic simulation (MD). By stretching and twisting individual DNA molecules, we measured the elasticity of DNA in the presence of ILs ([bmim]Cl and [omim]Cl). As results, the persistence length, stretch modulus, torsional stiffness and twist-stretch coupling exhibited a significant decrease compared to the DNA without ILs binding. Isothermal titration calorimetry analysis indicated that the ILs in the presence of DNA were thermodynamically favored driven by enthalpy and entropy. DNA underwent size transition and conformational change induced by ILs, and the charges of DNA were neutralized by the added ILs. The binding of ILs induced unwinding and softening of DNA. Circular dichroism spectra and MD results indicated that DNA maintained B-conformation after interacting with ILs. Compared to [bmim]+, [omim]+ showed stronger binding affinity to DNA and tended to aggregate on the DNA surface. ILs binding reduced Na+ and water binding on DNA, which likely prevented the hydrolytic reactions that denatured DNA and helped stabilize DNA for the long term. This research provides a critical theoretical foundation for the utilization of ionic liquids in life sciences. [ABSTRACT FROM AUTHOR]
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- 2024
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30. Separation of hematite and quartz in a cationic collector flotation system using Pullulan as a greener depressant.
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Zhao, Panxing, Liu, Wengang, Liu, Wenbao, Guo, Ying, Chen, Mengqiang, Mao, Yong, and Ding, Rui
- Abstract
• Pullulan was a green and efficient depressant of hematite in DDA reverse flotation. • Pullulan could enhance the hydrophilicity of the hematite surface. • Pullulan could adsorb on hematite surface through hydrogen bonding and chemical bonds. As the uncertainly of climate and the world situation intensifies, there are more and more pressures on resources and environment faced by human beings, the requirements for the development of mineral resources have become higher and higher. Iron mineral, as the most exploited mineral by mankind at present, the green and efficient purification of iron ore is an important means to realize energy saving and carbon reduction. In this paper, a novel hematite depressant—Pullulan (an environment friendly microbial polysaccharide, represented as PU thereafter), was introduced into the purification of hematite from quartz in cationic collector flotation system. Furthermore, a serious of surface tests were applied to explore the adsorption mechanisms between PU and the mineral surfaces. According to these experiments, it can be concluded as follows. The results of micro-flotation exhibited that PU showed better inhibition for hematite in DDA flotation system, the concentrate product with Fe grade of 65.88 %, and 91.06 % recovery was obtained from the artificial mixed minerals at 20 mg/L DDA, 15 mg/L PU at natural slurry pH. Wettability analysis suggested that PU could enable the hematite surface to become more hydrophilic, while little effect on wettability changes were observed on the quartz surface. The zeta-potential, FTIR and XPS analyses revealed that PU could occur adsorption on the hematite surface relying on hydrogen bonding with the hydrated hematite surface, and chemical complexation formed between the hydroxyl groups on PU and the Fe sites of the hematite surface. [ABSTRACT FROM AUTHOR]
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- 2024
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31. Capillary effects of submicron heterogeneities in aqueous solutions of sugars. The additional mechanism of microfluidics.
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Penkov, Nikita V., Zhmurin, Vasily A., Manokhin, Andrey A., Kobelev, Alexey V., and Penkova, Nadezda A.
- Abstract
• Submicron heterogeneities spontaneously form in aqueous solutions of sugars. • Submicron heterogeneities are destroyed in glass capillaries. • This factor may be an important mechanism of microfluidics. In this paper, we study submicron heterogeneities (SMH) that spontaneously form in aqueous solutions of sugars: glucose, fructose and sucrose, with a concentration of 0.5 mol%. These solutions were passed through glass capillaries with a diameter of about 6 and 13 µm, which led to a decrease in the concentration of SMH without significantly changing their size. For capillaries of smaller diameter, this effect is more pronounced. The decrease in the concentration of SMH is not associated with their mechanical destruction or adsorption on the surface of capillaries. This phenomenon is explained by the destruction of SMH as a result of their interaction with the hydrophilic surface of the capillary. The fundamental differences between the presence of SMH in microfluidic conditions and bulk reservoirs are discussed. This phenomenon should be taken into account in microfluidics. [ABSTRACT FROM AUTHOR]
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- 2024
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32. Molecular dynamics simulation on thermal and transport properties of LiF-KF.
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Yang, Qifan, Sang, Lixia, and Huang, Ji
- Abstract
• RNEMD method is applied to calculate the transport properties of binary LiF-KF. • Microstructures associated with thermal-transport properties are investigated. • The thermal conductivity increases exponentially with Li+ concentration. • The enhancement of thermal-transport properties of binary LiF-KF is studied. Molten fluoride is considered as an attractive heat transfer and storage medium in advanced energy utilization facilities, but it is short of the necessary thermal and transport properties at high temperature. In this paper, the thermal and transport properties of the binary LiF-KF mixtures at 1073–1473 K are obtained by classical molecular dynamics. The deviation of simulated thermal conductivity of binary LiF-KF at 1073 K from experimental value is less than 19 %. Moreover, the deviation of simulated viscosity of pure LiF at different temperatures from experimental value is around 10 %. It is indicated that reverse non-equilibrium molecular dynamics (RNEMD) is acceptable for describing fluoride salts. An exponential correlation is established between molar fraction of LiF and thermal conductivity at different temperatures. Furthermore, the macroscopic thermal and transport properties correlated with local structure are analyzed, especially the dependence of local structure on temperature and composition of LiF is discussed deeply. With temperature increasing, ion clusters are considered to be formed and overall structure become loose, which leads to reductions in density, thermal conductivity and viscosity. An increase in composition of LiF results in higher specific heat capacity, thermal conductivity and viscosity, which is related to the reduction of Li-Li bond length and the enhancement of interactions between F−. The comparison of properties enhancement of different compositions is completed through the analysis of the synergy coefficient of macroscopic properties. This work provides the basic data for the accurate design of high-temperature heat transfer system. [ABSTRACT FROM AUTHOR]
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- 2024
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33. Photocatalytic degradation of iohexol by photo-driven double Z heterojunction photocatalyst under strong internal electric field in synergy with peroxymonosulfate (PMS).
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Wu, Jie, Xu, Jingjing, and Chen, Mindong
- Abstract
• Double Z heterojunction g-C 3 N 4 /Bi 2 O 2 CO 3 /MnWO 4 with strong internal electric field was successfully prepared. • Under visible light irradiation, the double Z-scheme heterojunction g-C 3 N 4 /Bi 2 O 2 CO 3 /MnWO 4 coupled with the activation of PMS efficiently degrades 90.07 % of Iohexol within 40 min. • The catalytic system shows good cycle stability. • By constructing a double Z-scheme heterojunction, the electron transfer within g g-C 3 N 4 /Bi 2 O 2 CO 3 /MnWO 4 can be effectively facilitated, accelerating the electron transfer and enhancing the migration rate of photogenerated carriers. • Activating PMS can generate more reactive free radicals, among which, 1O 2 and h + are the main reactive radical and · OH, · SO 4 - and · O 2 – provided most of the help for the elimination of Iohexol. This paper describes the preparation of a double Z heterojunction photocatalyst, g-C 3 N 4 /Bi 2 O 2 CO 3 /MnWO 4 (CBCM), with a potent internal electric field using the hydrothermal method. The degradation efficiency can be further improved by combining photocatalytic technology with activated persulfate (PMS) technology. The synthesis of CBCM-7 was validated through XRD and TEM analyses, while XPS provided evidence of electron transfer and the establishment of heterojunctions within its structure. Additionally, PL, PC, and EIS measurements underscored CBCM-7′s proficient rate of photogenerated charge separation and robust charge transfer properties. The experimental results showed that the photocatalytic degradation of the iodinated contrast agent was substantially enhanced by this catalyst coupled with PMS. The degradation rate of Iohexol was up to more than 90 % within 40 min. After the completion of the recycling experiment, the degradation efficiency of this system remained above 80 %. Mechanistic analyses, including EPR tests, indicate that the main active groups generated by the degradation of this dual Z-scheme heterostructured photocatalyst coupled with activated PMS were superoxide radicals and hydroxyl radicals. [ABSTRACT FROM AUTHOR]
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- 2024
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34. Orientation time correlation functions up to the fourth cumulant for liquid water.
- Author
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Hsu, Chih-Chi, Chiu, Hung-Jen, Wang, Chi-Wei, and Wu, Ten-Ming
- Abstract
[Display omitted] • The fourth cumulant of orientational time correlation functions were derived. • Cumulants were calculated with stable rotational instantaneous normal modes. • The cumulant calculations were compared with simulation results for water. • The fourth cumulant produces an exponential decay at long times. • No fitting parameter was required in the cumulant calculations. The orientation time correlation functions (OTCFs) of molecular liquids are related to many experimental observations but subtle in theoretical calculations. Usually, the OTCFs at different timescales are described by distinct approaches. The OTCFs at short times were expanded into a series in an order of molecular angular velocity components, and the second cumulant (SC) of the series gave a single-frequency integral over one-mode propagation function weighted by a rotational density of states (DOS) of the liquid, whereas the OTCFs at long times displayed an exponential decay according to the Debye theory. In this paper, we derived the series of the OTCFs up to the fourth cumulant (FC), which gave a sum of twofold frequency integrals over two-mode propagation functions weighted by a product of two rotational DOSs associated with one or two molecular axes. With no need of any fitting parameter, the OTCFs calculated up to the SC and up to the FC were compared with simulation results for liquid water. With the power spectra of angular velocity autocorrelation function, which have a finite value at zero frequency, as the inputs, the OTCFs in both SC and FC schemes resulted in an exponential decay at long times, while the decay times were smaller than the simulation values. The positive results were the calculations with stable rotational instantaneous-normal-mode spectra, which have a linear behavior extrapolated to zero at low frequencies. As the stable rotational INM spectra were used as the inputs, the OTCFs in the SC scheme produced a slow power-law decay, but the OTCFs in the FC scheme captured the simulation behaviors from short to long timescale, including an exponential decay, with the decay times of the 2nd-rank OTCFs close to the simulation values. [ABSTRACT FROM AUTHOR]
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- 2024
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35. Stimuli-responsive materials for 4D Printing: Mechanical, Manufacturing, and Biomedical Applications.
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Kumar, Pankaj, Suryavanshi, Purushottam, Kumar Dwivedy, Santosha, and Banerjee, Subham
- Abstract
[Display omitted] • Four-dimensional printing involves utilization of intelligent materials in 3D printing process. • The process driven by stimuli and solvent responsive soft materials. • Materials undergo programmed shape changes over time when subjected to specific external stimuli. • 4D printed materials broaden their applications in various industries, including aerospace, biomedical, soft robotics, engineering, and fashion, potentially revolutionizing manufacturing. • Emerging smart materials exhibiting shape-changing capabilities and their reactions to internal or external stimuli. Four-dimensional printing (4DP) is an interesting field of study that integrates intelligent materials into three-dimensional printing (3DP). Using this method, objects that can gradually change form in response to environmental stimuli, such as moisture, electric or magnetic fields, UV light, temperature swings, pH variations, or alterations in the composition of ions, can be created. Intelligent materials, such as shape memory polymers, alloys, hydrogels, ceramics, and composites, which can react to external stimuli, are essential for 4DP. Unlike traditional 3D printing, the ability of 4D printed materials to undergo structural and/or property alterations expands their applications across industries such as aerospace, biomedical, soft robotics, engineering, and fashion, potentially revolutionizing manufacturing. This review provides an overview of current advancements in 4D printing and discusses both established and emerging smart materials with shape-changing capabilities and their responses to stimuli. It explores the differences between 4D and 3D printing technologies, traces the origins of 4D printing, and examines the materials involved, with emphasis on shape-memory polymers. This paper also highlights the applications of 4D printing in pharmaceuticals and biomedicine, particularly in dynamic polymers, and in the development of drugs for genetic diseases. In addition, it discusses progress in creating implantable biomedical devices and pharmaceutical medications. Despite being in its early stages, 4D printing technology has immense potential and promising exciting possibilities in the future. [ABSTRACT FROM AUTHOR]
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- 2024
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36. Experimental and molecular dynamics simulation study of the effect of composite surfactants on wetting of coal dust.
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Hao, Tianxuan, Jiang, Shan, Wang, Lei, and Jiang, Wan
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SURFACE tension , *IONIC surfactants , *CONTACT angle , *ANIONIC surfactants , *NONIONIC surfactants - Abstract
• By combining macroscopic experiments and microscopic simulations, the optimal combination of composite ionic surfactant solutions is derived, which can realize the efficient enhancement of the effect of dust reduction on coal dust. • The dynamic changes of surface tension and contact angle of different solutions were observed, and the microscopic wetting principles of each surfactant were characterized from their structural features by establishing their molecular models. • By constructing adsorption models containing two different ions, it was concluded that the nonionic and anionic surfactants had the most obvious longitudinal distribution between coal and water after compounding, which could form a tighter adsorption layer and allow water molecules to penetrate into the coal molecules, thus enhancing the wetting effect on coal dust. To improve surfactant wetting action on coal dust in the process of mine spray dust reduction, this paper adopts a combination of experiments and molecular simulation to study the wetting properties and mechanism of different kinds of active agents on coal dust and selects the compounded surfactants with better dust reduction effect. The results show that: fatty alcohol polyoxyethylene ether can reduce the surface tension to 34.16 mN·m−1, which is 35.84 mN·m−1 comparatively less than that of pure water; dodecylphenol polyoxyethylene ether and poly(ethylene glycol) octyl phenyl ether have the maximum electrostatic potentials of 0.0892 a.u and 0.0908 a.u, which exceed that of water molecules, which indicate that the nonionic active agents are the most polar, and it is easy for them to form the hydrogen bonding with water, and the ability to reduce surface tension is superior to other types of active agents; molecular simulation results show that the non + anionic complex system can form a tighter adsorption layer between coal and water, so that the water molecules move more vigorously, moving from the molecules of water to those of coal, thus producing a better wetting effect than the monomer active agent. In addition, dust settling experiments and particle size experiments were conducted to verify the reasonableness of the microscopic simulation. The study's findings can provide a reference for identifying and designing compounded surfactants with excellent wetting performance to improve the dust reduction effect. [ABSTRACT FROM AUTHOR]
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- 2024
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37. Fighting poison with poison: Degradation of ethyl paraben by Bi2Ti2O7-TiO2 doped with ethyl paraben.
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Liu, Xian and Wang, Xun
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- *
MOLECULAR imprinting , *TITANIUM dioxide , *ELECTRON transitions , *POISONS , *PHOTODEGRADATION - Abstract
[Display omitted] • The effect of bismuth on molecularly imprinted titanium dioxide was investigated. • Selective photocatalytic removal of ethyl paraben achieved. • Addition of ethyl paraben to achieve enhanced degradation of ethyl paraben. In this paper, a variety of titanium-bismuth-based composite photocatalysts were prepared by molecularly imprinted sol–gel method using ethyl paraben (EP) as the target pollutant and tetra-n-butyl titanate as the precursor for the degradation of EP. The photocatalytic removal of 81.4 % of 10 mg/L EP wastewater was achieved by synthesising Bi-EP-TiO 2 for 30 min at 500°C, 5 g Bi and 2 g EP. The main component of the prepared Bi-EP-TiO 2 and Bi-TiO 2 is Bi 2 Ti 2 O 7 -TiO 2. In addition, the forbidden bandwidth of Bi-EP-TiO 2 is 0.28 eV larger than that of Bi-TiO 2 but 0.30 eV smaller than that of TiO 2 , which suggests that, compared with TiO 2 , Bi-EP-TiO 2 requires a lower electron-leap energy, which is capable of generating more. This suggests that Bi-EP-TiO 2 requires lower electron transition energy than TiO 2 , and therefore can generate more photogenerated electron holes, thus improving the catalytic efficiency. Hence, Bi 2 Ti 2 O 7 -TiO 2 doped with ethyl paraben degrades EP with excellent performance. [ABSTRACT FROM AUTHOR]
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- 2024
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38. An SFG study of the effects of salts on MIBC adsorption and foamability.
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Nguyen, Cuong V., Nguyen, Anh V., Nguyen, Ngoc N., and Phan, Chi M.
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- *
NONLINEAR optics , *SURFACE tension , *SALINE waters , *WATER use , *MINERAL processing - Abstract
[Display omitted] • The interplay between MIBC and NaCl at air–water interface was investigated. • Surface-sensitive SFG spectroscopy, tensiometry and foamability experiments were applied. • Synergistic and antagonistic effects of NaCl on MIBC adsorption were revealed. • The new insights provide hints to designing new surfactant molecules. Methyl isobutyl carbinol (MIBC) is an alcohol-based surfactant and is widely used as a frother in the industry. Classical studies of MIBC adsorption by tensiometry fail to elucidate the mechanism(s) governing the frothing power of MIBC in the presence of salts. In this paper, sum-frequency-generation vibrational spectroscopy (SFG) is employed to study the adsorption of MIBC at the air-saline water interface and relate it with foamability and surface tension. The interface-specific spectroscopic experiments using non-linear optics SFG allowed detecting the change in the orientation and surface excess of MIBC molecules at the interface versus their bulk concentrations. At a concentration of MIBC of approximately 20 mM, the surface excess of MIBC stops increasing, implying the saturation of adsorption at the topmost monolayer. At this concentration, the antagonistic (salting-down) and synergistic (salting-up) effects of NaCl on the MIBC adsorption can be detected at low and high NaCl concentrations, respectively. At MIBC concentrations being either lower or higher than 20 mM, only a synergistic effect of NaCl is observed but with different underlying mechanisms. The finding is supported by the experimental results of foamability but cannot be explained by the results of continuously decreasing surface tension due to the adsorptions at the topmost monolayer and within the under-monolayer region at the MIBC concentration above 20 mM. This study provides insights into the frother-salt interaction and the role of the under-monolayer adsorption in controlling interfacial properties, stimulating further research and saline water use for a sustainable mineral industry. [ABSTRACT FROM AUTHOR]
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- 2024
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39. Deep eutectic solvent-immobilized magnetic nanoparticles as a capable catalyst for the green synthesis of triazolopyrimidines.
- Author
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Benrashid, Amin, Habibi, Davood, and Beiranvand, Masoumeh
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- *
IRON oxide nanoparticles , *IRON oxides , *SUSTAINABLE chemistry , *FIELD emission electron microscopy , *HAZARDOUS substances - Abstract
Synthesis of D , 4(a-d) and 4′(e-o) [Display omitted] • Preparation of a novel magnetic choline chloride-based deep eutectic solvent immobilized on Fe 3 O 4 magnetic nanoparticles (D). characterization of D. • Application of D as a capable catalyst in the synthesis of triazolopyrimidines. One of the principles of green chemistry is the use of catalysts to prevent and eliminate hazardous chemicals. Recently, remarkable developments have been made in the field of green catalysis, the design of safer chemicals, and green solvents. In this paper, novel magnetic choline chloride-based deep eutectic solvent immobilized on Fe 3 O 4 magnetic nanoparticles (Fe 3 O 4 @SiO 2 @THAM@ChCl = D) was obtained from the sequential synthesis of Fe 3 O 4 (A), Fe 3 O 4 @SiO 2 (B), and Fe 3 O 4 @SiO 2 @THAM (C), and characterized with various techniques such as Fourier transform–infrared spectroscopy (FT–IR), energy–dispersive X-ray spectroscopy (EDX), elemental mapping, vibrating sample magnetometer (VSM), field emission scanning electron microscopy (FE–SEM), transmission electron microscopy (TEM), thermo–gravimetric–differential thermal analysis (TGA–DTA) and X-ray diffraction analysis (XRD). TEM images confirm that the nanoparticles are core–shell. Then, the novel D was used as a capable heterogeneous catalyst for the one-pot three-component condensation reaction of 3-amino-1,2,4-triazole, aromatic aldehydes, and malononitrile for the synthesis of 1,2,4-triazolo[4,3- a ]pyrimidines under solvent-free conditions with high yields and short reaction times. Some advantages of using this catalyst are the novelty, easy separation from the reaction medium, reusability, high thermal stability, excellent yield, and short reaction times. [ABSTRACT FROM AUTHOR]
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- 2024
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40. Research on the effect of DES properties on the preparation of h-BN nanosheets by electrochemical-liquid phase exfoliation method.
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Ding, Qihui, Shan, Qian, Zhang, Qi, Chen, Mengda, Cai, Ding, and Wu, Wei
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- *
CHEMICAL stability , *NANOSTRUCTURED materials , *THERMAL stability , *SURFACE area , *BIOCOMPATIBILITY - Abstract
[Display omitted] • The type and properties of DES have a significant impact on the electrochemical exfoliation of BNNSs. • The intercalation effect of DES and the compatibility between DES and h-BN were the main factors affecting the yield. • The quality of BNNSs mainly depended on the decomposition and expansion effect of DES. • This rule also can be applied to prepare highly conductive and hydrophilic two-dimensional material Ti-MXene. Hexagonal boron nitride (h-BN) with a large specific surface area and unique optoelectronic properties has good application prospects in many fields. The liquid phase exfoliation method is considered the most promising method for achieving controllable preparation of boron nitride nanosheets (BNNSs), but the low-cost, relatively environmentally friendly and efficient liquid phase exfoliation is still difficult to achieve. Choosing a suitable solvent system is the key to achieving efficient exfoliation. Deep eutectic solvents (DESs) have the advantages of simple synthesis, low cost, high thermal and chemical stability and strong biocompatibility and are expected to be green solvents for preparation of BNNSs. In this paper, it was found that the properties of DESs and its interaction with h-BN had a significant impact on the electrochemical exfoliation of h-BN. The intercalation effect of DES and the compatibility between DES and h-BN were the main factors affecting the yield, while the quality of BNNSs mainly depended on the decomposition and expansion effect of DES. This rule also can be applied to prepare highly conductive and hydrophilic two-dimensional material Ti-MXene. This research explores the structure–activity relationship between two-dimensional materials and DESs, and provides a theoretical basis for the environmentally friendly and efficient preparation of two-dimensional materials using DESs as exfoliation solvents. [ABSTRACT FROM AUTHOR]
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- 2024
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41. Thermodynamic study on the dissolution of lithium cobaltate in the cathode of spent lithium-ion batteries recovered from supercritical water.
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Meng, Tian, Lu, Hang, Chen, Jingwei, and E, Jiaqiang
- Subjects
- *
SUPERCRITICAL water , *THERMODYNAMIC laws , *LITHIUM-ion batteries , *MOLECULAR dynamics , *METAL compounds , *EQUATIONS of state - Abstract
[Display omitted] • The thermodynamic dissolution law of LiCoO 2 in SCW was obtained. • The dissolution process of LiCoO 2 in SCW was simulated using MD. • The solubility of the product in SCW was calculated using the R-HKF model. • The effect of reaction parameters on solubility of LiCoO 2 in SCW was studied. The recovery of cathode metal materials in lithium-ion batteries using supercritical water (SCW) has attracted more and more attention. To explore the separation and extraction method of LiCoO 2 using SCW, the thermodynamic experiments of LiCoO 2 dissolution in SCW were carried out in this paper to study the effect of essential parameters on the solubility of LiCoO 2 in SCW. The results show that the solubility decreases with an increase in temperature and increases with an increase in pressure and density. The molecular dynamics were applied to simulate the dissolution process of LiCoO 2 and provide a theoretical explanation for the experimental law. The solubility of LiCoO 2 in SCW was also calculated using the R-HKF equation of state, and high-precision prediction results were verified using experimental data. This work will provide a reference for obtaining the solubility of cathode metal compounds of spent lithium-ion batteries in the supercritical state. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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42. Synergistic enhancement of NC-GCN/Ag2O photocatalytic reduction of uranium by D-A and p-n junction structures.
- Author
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Li, Zhouzhou, Li, Zheng, He, Feng, He, Wen, Chen, Qixu, and Wang, Hongqing
- Subjects
- *
PHOTOREDUCTION , *P-N heterojunctions , *COMPOSITE materials , *CRYSTAL structure , *URANIUM - Abstract
[Display omitted] • Synthesis of a new U(VI) catalyst for photocatalytic reduction, NC-GCN 10 /Ag 2 O(1:2). • A new strategy to enhance the performance of materials for photocatalytic reduction of U(VI). • Intramolecular D-A structure and p-n heterojunction co-promote the photocatalytic performance of GCN. • The removal efficiency of U(Ⅵ) by NC-GCN 10 /Ag 2 O(1:2) photocatalyst was seven times as much as GCN. • A mechanism of photocatalytic reduction of U(VI) was proposed. Recently, how to improve the photocatalytic uranium removal performance of Graphite-phase carbon nitride (GCN) has always been a hot research topic. In this paper, a new strategy based on p-n junction and D-A structure is proposed to improve the photocatalytic performance. And as a result, a novel cyano modified photocatalytic material NC-GCN/Ag 2 O was designed and prepared for the reduction of U(VI). Interestingly, the material shows better adsorption performance for U(VI) in the dark treatment stage, and its removal of U(VI) is close to 70 % under the initial U(VI) concentration of 20 ppm and the solid–liquid ratio of 0.2 g/L. And the adsorption is in accordance with the Langmuir model and Pseudo second order model. After 30 min of illumination, the removal rate of U(VI) can reach 93.2 %, significantly higher than that of GCN (13.6 %) and NC-GCN 10 (37.7 %). It's worth mentioning that photocatalytic reduction dominated the adsorption-reduction process for U(VI) removal after light exposure. In addition, after four cycles, the removal of U(VI) from the composite material decreased by only 5 % with no change in the crystal structure, i.e., it has good reusability and stability. Meanwhile, there was no significant interference with other ions except for Cu2+ and V5+, which had a weak interference. Finally, a new mechanism for U(Ⅵ) reduction was proposed. [ABSTRACT FROM AUTHOR]
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- 2024
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43. Unveiling the molecular insights of 2-(carboxymethyl) benzoic acid: A density functional theory approach towards structural and biological attributes.
- Author
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Sundaram, S., Praveena, R., Cheerlin Mishma, J.N., Shashwath, V.R., Joseph, Ginson P., Balasubramanian, V., Muthu, S., Chakravarty, Sujay, and Vijayakumar, V.N.
- Subjects
- *
POTENTIAL energy surfaces , *DENSITY functional theory , *MOLECULAR docking , *HYDROGEN bonding , *MORPHOLOGY - Abstract
[Display omitted] • Global reactive parameters, structural and topological studies provides the clear insight of the compound. • Chemical reactivity of the 2-(Carboxymethyl)benzoic acid is analyzed by MEP study in different solvent phases. • Enhanced NLO parameters provide favourable nonlinear optical applications. • Molecular docking studies verify the title compound's potent anticancer activity and its bioactive characteristics. Nowadays density functional theory (DFT) is one of the best methods to explore the vibrational modes and structure of the biological system. Quantum mechanical calculations are performed using gas phase and different solvents (DMSO, methanol and water). The derived global reactive parameters, structural and topological study provides the clear insight of the 2-(Carboxymethyl) benzoic acid. Depth studies of DFT proves the existence of hydrogen bonds between donor and acceptor in the compound, which is supportive for the biological applications. In this paper, different experimental and computational simulated FT-IR, FT-Raman, UV–Vis spectral studies are used to explicate vibration assignments of the 2-(Carboxymethyl) benzoic acid. Experimentally observed vibrational frequency is compared with theoretically simulated spectrum. B3LYP method with 6–311++G (d, p) basis set is used in DFT to optimize the 2-(Carboxymethyl)benzoic acid structure. The most stable lower energy conformer is identified using potential energy surface (PES) analysis using Gaussian 16 W software. ESP, HOMO-LUMO, NBO, and QTAIM calculations have evinced an adequate electronic characterization of 2-(Carboxymethyl) benzoic acid. Further, van der Waals and steric interactions among 2-(Carboxymethyl) benzoic acid have been discussed with the help of RDG study. Hirshfeld surface studies establish the existing various interaction among molecules and total packing arrangement of the crystal structure. Due to the high biological activity score, 2-(Carboxymethyl) benzoic acid is a good therapeutic candidate. Lipophilicity analysis of 2-(Carboxymethyl)benzoic acid clearly explicates the bioactivity properties and its effective drug applications. Further, molecular docking investigates that the compound can be used as anticancer medication. The detailed DFT study of the 2-(Carboxymethyl) benzoic acid justified its biological applications of the present communication. The calculated NLO parameters of 2-(Carboxymethyl)benzoic acid evidenced for good efficacy in diverse filed application has been discussed. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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44. Study on expanding flotation performance differentiation of quartz and magnesite by amino-trimethylphosphonic acid in dodecylamine system.
- Author
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Cheng, Tianyu, Xing, Dingquan, Shen, Zhengchang, Ma, Shuai, Shi, Shuaixing, Deng, Jianying, and Deng, Jiushuai
- Subjects
- *
MAGNESITE , *PHOSPHONIC acids , *ZETA potential , *CYCLOPROPANE , *FLOTATION - Abstract
[Display omitted] • ATMP has a strong depression effect on magnesite; • ATMP can achieve the separation of magnesite from quartz; • ATMP chelated with active site Mg2+ on the magnesite surface through –PO 3 group; • DFT was used to calculate the adsorption energy of ATMP on the magnesite surface. In this paper, amino trimethylene phosphonic acid (ATMP) was introduced into the separation process of magnesite and quartz, in order to reduce the content of associated minerals in magnesite and improve the industrial utilization value of magnesite. Micro-flotation tests showed that under the system of dodecylamine as collector, ATMP can selectively depress magnesite within the alkaline pulp environment. When the dosage of ATMP was 100 mg/L and the pulp pH was 11, the flotation recovery of magnesite was 12.65 % and that of quartz was 91.00 %. Additionally, the findings of the artificial mixed mineral flotation showed that a concentrate with a grade of 43.53 % MgO and a recovery of 91.03 % was achieved. Zeta potential, FTIR and XPS analyses demonstrated that ATMP chelated with the active site Mg2+ on the surface of magnesite through –PO 3 group. In addition, DFT calculation indicated that the adsorbed ATMP increased the distance of N atom in dodecylamine (DDA) to the surface of magnesite from 2.671 Å to 5.106 Å. The interaction energy between DDA and magnesite increased from −201.28 kJ/mol to −136.75 kJ/mol, resulting in it difficult for DDA to adsorb on the magnesite surface. However, ATMP was difficult to adsorb on the quartz surface and had no effect on the interaction between DDA and quartz. Therefore, the selective depression effect of ATMP on magnesite was realized. [ABSTRACT FROM AUTHOR]
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- 2024
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45. Natural polymers and electrolytes enhanced coal dust suppression and explosion prevention: New insight from experimental and molecular dynamic simulations.
- Author
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Ding, Xuhan, Yang, Yong, Wang, Kai, Luo, Zhenmin, Fu, Qingyun, Wang, Tao, and Yi, Xin
- Subjects
- *
DUST explosions , *BIOPOLYMERS , *POLYELECTROLYTES , *COAL dust , *DYNAMIC simulation , *IONIC structure - Abstract
[Display omitted] • Natural polymers and electrolytes enhance dedusting and explosion prevention. • Dust suppression is jointly affected by wetting and agglomerating behaviour. • Wettability is affected by the diffusion coefficient and absolute wetting area. • Electrostatic potential energy and hydrogen bond are significant to agglomeration. • The neutralization between ions significantly reduces the reactivity of coal. This paper expressed a new insight including experimental and molecular dynamic simulations to illuminate multi-scale mechanisms of coal dust suppression and explosion prevention when applying natural polymers and electrolyte. Results reveals that the addition of natural polymers and electrolyte achieve a maximum 11.85% improvement on dedusting rate and 36.36% improvement on suppression speed when compares with the individual application of SDBS, the MIE and MITC also receives a maximum 1.5 times and 23.58% improvement as well. This achievement is jointly affected by the wetting and agglomerating behaviour between suppressant and coal particles. The chain-like ionic structure and two benzene rings offer LS-Na exhibits good planarity in space and can vertically embed into the surface of coal particles. The lower diffusion coefficient and larger wetting area brings LS-Na stronger ability to help SDBS adsorbing on the coal particles and therefore exhibit better wettability. However, higher electrostatic potential difference endows CMC-Na stronger ability to absorb H 2 O molecules to form more viscous liquid environment. More hydrogen bond and higher bond energy of CMC-Na could promote the agglomeration of coal particles. The kinetic analysis reveals that the activation energy of coal particles treated by ternary suppressant is higher than that of binary ones. With the help of neutralization reactions between Na· and Cl· generated by molten NaCl and H· and OH· generated by the combustion, the reactivity of coal particles has been diminished and the combustion chain has been interrupted. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
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46. Synthesis and investigation of acrylamide and 2-acrylamido-2-methylpropanesulfonic acid copolymer-modified graphene oxide nanomaterials with intensive viscosification capacity: An experimental and molecular dynamics study.
- Author
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Jia, Han, Jia, Haidong, Wang, Qiuxia, Wei, Xin, Yan, Hui, Wang, Yuanbo, Wang, Qiang, Lv, Kaihe, and Huang, Pan
- Subjects
- *
GRAPHENE oxide , *MOLECULAR dynamics , *POLYMER networks , *ACRYLAMIDE , *NANOSTRUCTURED materials , *INTERMOLECULAR interactions - Abstract
[Display omitted] • The AM-AMPS polymer modified GO material (GAA) was firstly synthesized. • The viscosification ability and aqueous stability of GAA molecules were affected by AMPS contents. • The more complexed topological network appeared in GAA system. • The GO segment in GAA increased the intermolecular dispersion attraction and the hydrogen bond. The polymer-modified nanomaterials with spontaneously generated cross-linked network greatly improve the dispersion viscosity, which is crucial for extending the sweep range and enhancing oil recovery. Recently, graphene oxide (GO) nanosheets have attracted extensive attention due to their high chemical reactivity and specific surface. In this paper, the AA molecule, synthesized by acrylamide (AM) and 2-acrylamido-2-methypropanesulfonic acid (AMPS) copolymerization, modified GO nanosheets (GAA) material is firstly synthesized and characterized. With the same content of AMPS segments, GAAn systems consistently exhibit better dispersion stability than AAn systems, along with higher absolute zeta potential values. The comprehensive investigation on the rheological property of GAA system reveals that GAA15 with the highest AMPS content exhibits the largest zero-shear viscosity (409.27 mPa·s) and the longest relaxation time. Based on the molecular dynamic simulation approaches, the aggregation morphology and stability of AA and GAA molecules are evaluated via the configuration analysis and the statistics of hydrogen bond numbers. The abundant binding sites from GO segments of GAA promote additional hydrogen bonds between GAA molecules and water, resulting in a more stable configuration. Molecular surface potential analysis and the independent gradient model based on Hirshfeld partition (IGMH) methods are further used to visualize the non-bonded interaction existed in cross-linked networks, which also predict and validate non-bonding interaction sites among molecular segments. The simulation results indicate higher viscosity in the GAA system should be ascribed to the formation of dispersion-strengthened cross-linked structures (AM-GO plane and GO-GO stacking segments). In summary, the microscopic viscosity-increasing mechanism of novel GAA system is proposed from the perspective of intermolecular interactions, which lays a preliminary theoretical foundation for the application of GAA material in the oil industry. [ABSTRACT FROM AUTHOR]
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- 2024
- Full Text
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47. Exploring the in-situ conversion of intermolecular hydrogen bonds into static electricity through experimental and theoretical methods.
- Author
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Chen, Zhuangzhuang and Shao, Huibo
- Subjects
- *
STATIC electricity , *SCANNING electrochemical microscopy , *MOLECULAR structure , *DENSITY functional theory , *ELECTRIC potential , *HYDROGEN bonding - Abstract
[Display omitted] • The in-situ conversion of hydrogen bonds into static electricity on the simulated biomembrane surface was investigated using SECM. • The number of hydrogen bonds at different pH was characterized by voltammetry and Approaching curves. • The intensity of in-situ conversion can be controlled by changing applied potential. • The key sites of weak interactions were visualized based on theoretical calculations. • Explored the influence of ion pairs on conversion intensity. In order to deeply understand the mechanism of biological function, it is significance to study conversion of weak interactions at the biomembrane surface. In this paper, the 3-mercaptopropionic acid self-assembled monolayer (3-MPA SAM) was constructed as a simplified model to simulate biomembrane, in which ferrocene carboxylic acid (FcCOOH) is adsorbed on the membrane surface through hydrogen bonds. Under positive potential induction, the in-situ conversion of hydrogen bonds into static electricity was investigated using scanning electrochemical microscopy (SECM). The conversion mechanism was the positive potential promoting the dissociation of carboxylic acids (COO−) on the membrane surface, followed by electrostatic attraction with the oxidation products (Fc+COOH). The study also found a positive correlation between conversion rate and potential value. Based on density functional theory (DFT), relevant information such as molecular structure, electrostatic potential and binding energy were obtained, and key sites of weak interactions were visualized using a reduced density gradient (RDG). The universality and competitiveness of conversion have been confirmed in different environments. This work provided some reference for revealing the properties and variations of weak interaction conversion at the biomembrane surface. [ABSTRACT FROM AUTHOR]
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- 2024
- Full Text
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48. Flexible, easy-to-produce, gradient distributed pitch broadband infrared reflectors with polymer-stabilized cholesteric liquid crystals.
- Author
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Liu, Yutong, Yuan, Xinpei, Xie, Mengqi, Liu, Zhidong, Zhao, Xiaohui, Cao, Hui, Wang, Huihui, Yang, Zhou, Wang, Dong, and He, Wanli
- Subjects
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CHOLESTERIC liquid crystals , *POLYMER liquid crystals , *LIQUID crystals , *POLYMER networks , *INFRARED equipment , *REFLECTANCE , *POLYMER films - Abstract
[Display omitted] In this study, we propose a simpler method to fabricate single-layer polymer cholesteric films with reflective bandwidth over 1500 nm instead of the previous multilayer films. We add polymerizable chiral compounds and non-polymerizable chiral compounds with the same rotation direction into the liquid crystal mixing system. Due to the presence of photoinitiators and UV-absorbing dyes, when UV light irradiates the polymerization, the polymerizable monomers, including the polymerizable chiral compounds, are rapidly polymerized in the near-light side, and the non-polymerizable monomers, including the non-polymerizable chiral compounds and partial monoacrylate monomers, do diffusion movement towards the far-light side, and after the anchoring action of the polymer network, the formation of the small-large-small pitch gradient distribution is realized, which results in the broadband reflection. In the paper, the effect of multiple factors on the reflection broadband of the film is explored, and the polymer-stabilized cholesteric liquid crystal (PSCLC) film with a reflection bandwidth of 1572 nm is successfully prepared, which is demonstrated to have many desirable properties, including thinness and flexibility. The flexible CLC films reported in this study are expected to be promising prospects for several applications such as shielding infrared devices, energy-efficient windows for automobiles, and modern building facades. [ABSTRACT FROM AUTHOR]
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- 2024
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49. Broad-band absorption and photo-thermal conversion characteristics of rGO-Ag hybrid nanofluids.
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Huminic, Gabriela, Vărdaru, Alexandru, Huminic, Angel, Fleacă, Claudiu, and Dumitrache, Florian
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NANOFLUIDS , *SOLAR collectors , *ETHYLENE glycol , *SILVER nanoparticles , *ABSORPTION , *GRAPHENE oxide - Abstract
• A new hybrid nanofluids, rGO-Ag/water and rGO-Ag/water + ethylene glycol were prepared. • Optical and photo-thermal properties of hybrid nanofluids were experimentally tested. • Both hybrid nanofluids achieve superior solar absorption. • The PTE performance was enhanced at low concentrations of hybrid nanofluids. In the current paper, the thermo-physical, optical and photo-thermal conversion characteristics of reduced graphene oxide nanosheets and silver nanoparticles suspended in water and water + ethylene glycol solution (1:1) were experimental investigated under indoor conditions. The results indicated that the hybrid nanofluids have a good solar absorption in both visible and near-infrared regions (220–1400 nm). Comparing transmission spectra and extinction coefficients of rGO-Ag/water and rGO-Ag/W + EG hybrid nanofluids it is found that the use of rGO-Ag/W + EG hybrid nanofluid is much more beneficial than the rGO-Ag/water nanofluid in solar applications. The rGO-Ag /water and rGO-Ag /W + EG hybrid nanofluids with 0.10 wt% exhibit a relative increase in the temperature difference by about 21 % and 37 % compared to the base fluids and also stored energy values of 4989 J and 5432 J respectively, after an irradiation time of 60 min. This study emphasized the solar potential of rGO-Ag hybrid nanofluids for improving the direct absorption solar collectors performance. [ABSTRACT FROM AUTHOR]
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- 2024
- Full Text
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50. A new phenoxazine-indanedione turn-on fluorescent probe with ultra-sensitivity for detecting hydrazine and its application in drinks, human urine and water samples and colorimetric test strips.
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Wang, Tao, Ma, Wenwen, Xing, Shu, Wang, Xingjian, Ren, Huijun, Hu, Tingting, Niu, Qingfen, Chen, Jianbin, and Ding, Yunqiao
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FLUORESCENT probes , *HYDRAZINE , *WATER sampling , *ENVIRONMENTAL health , *HYDRAZINES , *SILICA gel - Abstract
[Display omitted] • A new phenoxazine-indanedione based turn-on fluorescent probe PI was developed for N 2 H 4 detection. • PI shows significant advantages of high-specifity and ultra-sensitivity with an extreme low-detection-limit of 0.85 nM. • PI-laden colorimetric test strips were developed for real-time and on-site visual detection of gaseous and aqueous N 2 H 4. • PI could be applied as a powerful tool to quantitatively detect N 2 H 4 in water, drinks and bio-fluid. Considering that hydrazine (N 2 H 4) is a suspected carcinogen and shows severe toxicity to ecological and human health, thus, the effective detection of N 2 H 4 is an urgent need throughout the globe. In this work, a new phenoxazine-indanedione turn-on fluorescent probe PI was developed and applied for visually/ultra-sensitively monitoring N 2 H 4 in aqueous media. A brilliant green fluorescence lighting-up response of probe PI was achieved upon the N 2 H 4 adding. The N 2 H 4 detection by probe PI shows significant advantages of high-specificity, favorable pH working range (3 ∼ 11), and ultra-sensitivity with an extreme low-detection-limit (0.85 nM). The mechanism for N 2 H 4 detection was ascribed to the N 2 H 4 -induced C = C breakage, which was proved by the spectral means and DFT investigations. Probe PI -laden silica-gel, and paper/TLC strips were conveniently constructed for on-site and real-time visual monitoring gaseous and aqueous N 2 H 4 , demonstrating its potential application value. More importantly, the PI could accurately and ultra-sensitively monitor trace amounts of N 2 H 4 in real samples such as drinks, water and human urine with high precision. Overall, this work provided a new valuable turn-on fluorescent probe for ultra-sensitively detecting N 2 H 4. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
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