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Over the past few decades, studies have focused on nanomaterials with enzyme-like features (nanozymes) as simple, stable, high-performance alternatives to natural enzymes in a wide range of implementations. A variety of inorganic nanomaterials including Cd, carbon based nanomaterials, CeO2, Co3O4, CuO, Au, Fe, Mn, Pd, Pt, SiO2, Ag, VO2, and Zn NPs have been considerably used to mimic the activity of naturally occurring enzymes. These nanomaterials have shown to mimic extensively enzyme-like activities, and great progresses have been made in these systems due to the enormous development in nano-research and the distinctive properties of nanomaterials. To accentuate the growth in the field of nanozymes, this review considers different inorganic nanomaterials that have been investigated to mimic peroxidase-like enzyme in biological, chemical and medical applications. We discuss regarding the kinetics, mechanisms and applications of peroxidase-like nanozymes. Finally, we will discuss regarding the different parameters that influence the catalytic activity of nanozymes and focus on the current challenges and future outcomes.

Crocin has a strong Two-photon Absorption (TPA) capability that makes it suitable for medicine and photonic devices. To study the linear and nonlinear optical properties of crocin in solvent and Microemulsion (MEs), Z-scan instruments, Uv–Vis, and fluorescence were used. Nonlinear absorption coefficient (β), nonlinear refractive index (n2), third-order susceptibility (χR), and second-order molecular hyperpolarizability (γR) values were extracted from the Z-scan instrument. The β and n2 reduce with the increase in solvent's dielectric constant (e). In crocin mixed with MEs, the nonlinear optical values depend on the size and concentration of the droplet at constant crocin concentration. The MEs can enhance the value of β as compared with other solvents. A red shift in absorption spectra of crocin was observed with an increase in e. However, the absorption peak was constant in the MEs. The ratios of the excited state to the ground state of the dipole moments (μe/μg) of crocin in the solutions were determined by the quantum perturbation theory. It was shown that μe/μg has similar behavior with 1/γR. The value of μg and γR are reduced with an increase in e.

Temperature dependency of infrared band intensity for methylene rocking vibration could be used as indication for creation of solid crystals while decreasing temperature. In this work, different experiments were conducted to measure wax appearance temperature, WAT, such as cross polarized microscopy, rheometry and FTIR spectroscopy. Three Iranian crude oils were characterized based on the SARA test and PC-SAFT model was developed to predict WAT. The obtained results by FTIR spectroscopy and PC-SAFT model were in quite agreement. FTIR spectroscopy determined higher WAT values which may be due to its higher sensitivity to smaller wax crystals. Also, the effect of a polymeric crystal modifier (EVA) and an aromatic solvent (toluene) on wax precipitation was investigated. EVA dramatically decreased the pour point of lower waxy crude oils. Toluene dissolved polar compounds such as asphaltene and consequently decreased WAT and pour point. This observation confirmed that asphaltene supports the wax crystallization and its growth.

It is a fact that utilizing additives is a effectual approach to create an ameliorated concrete, but researchers still have a long way to gain a deep insight of the manner of interior and surface interactions of this components at the molecular scale. The objective of this study is merging nano-silica/zinc-titanate nanoparticles(NZ), zinc-titanate nanoparticles/Dawson(DZ), nano-silica/Dawson(ND), and nano-silica/zinc-titanate nanoparticles/Dawson(NDZ) with ordinary and self-compacting concrete(SCC) to specify the surface and interface interactions, and hydrogen bonds as well as their influences on the mechanical properties of mentioned concretes. Through the quantum mechanical studies, the adsorption energies for optimized geometries of NZ, DZ, ND, and NDZ perused, and NDZ was determined as the most stable structure with more and stronger formed hydrogen and partially covalent bonds. From the value of absorption energies point of view, NZ, ND, and DZ functioned much weaker than what NDZ did, so NDZ has the most binding energy. Accordingly, the use of NDZ could make the system substantially stable and rose the amount of adsorption. In another track, ordinary concrete and SCC including the dosage of 1–5% of NZ, DZ, ND, and NDZ were tested for compressive, tensile and flexural strength. The percentage of water absorption after 0.5, 24 and 72 h and the rate of concrete creep strain after 50, 150 and 250 days were determined. The experimental studies reported an increase up to 34.6%, 10.1%, and 15.6%, respectively, for compressive, tensile and flexural strength of ordinary concrete. This optimum growth obtained for compressive, tensile and flexural strength of SCC as 35%, 14.9%, and 24.5%, respectively. These trends were in line with quantum mechanical studies, and the same sequence observed for adsorption energies. It is also clarified that this growth in strength could be considered as a function of the hydrogen bonds and other interactions on the surface of the additives. This area of research due to its interdisciplinary nature would own many potentials to be pioneering with creating an opening gateway to connect sciences and engineering like chemistry, material science, nanotechnology, and field of engineering to encourage a broad spectrum of contribution in the engineering sciences and applications.

Despite the fact that additives ameliorate the concrete compressive strength, details about how they interact together on the surface at molecular scale have remained unknown. Our objective is incorporating nanosilica-polyamide(NP), polyamide-Keggin(PK), nanosilica-keggin(NK), and nanosilica-polyamide-Keggin(NPK) into concrete to investigate DFT calculations for clarifying the surface and interface interactions accompanied by experimental investigations. Adsorption, interaction, and deformation energies for optimized geometries of NP, PK, NK, and NPK investigated using DFT calculations. The optimized structure on NPK demonstrated that stronger and more hydrogen bonds formed on the surface. The adsorption(interaction) energy of NPK was more negative than those of NK, PK and NP. Therefore, utilizing NPK made the system considerably stable and increased the adsorption amount. In the experimental section, concrete cubes (150 × 150 × 150 mm) containing 1–5% of NP, PK, NK, and NPK examined. The 7-day and 28-day compressive strength, and 30-min, 24-h and 72-h water absorption obtained. The results illustrated an increase up to 38.6% in concrete compressive strength which was belonged to NPK, and it also consistent with the DFT calculations. The same sequence observed for adsorptions, interactions and deformation energies. They also showed an increase in compressive strength as a function of the hydrogen bonds on the additives surface. This study, will open up new possibilities for using these materials in concrete technology to produce stronger concretes would result in environmental advantages along with application in key concrete elements using in field of civil engineering.

Solubility of CO2 in the hybrid solvents composed of aqueous N-methyldiethanolamine (MDEA) blended with 1-methyl-3-octyl-imidazolium tetrafluoroborate ([Omim][BF4]) ionic liquid (IL) was measured at temperatures from (298.15–343.15 K) and pressures of (0.2–4 MPa). The experimental trials were performed in a static high pressure equilibrium cell to determine the CO2 absorption capacity of novel absorbent solutions based on the isochoric saturation technique. The experimental data showed that, by rising the concentration of IL in the absorbent solutions’, the mole fraction of dissolved CO2 gas enhances gradually. Absorption capacity of these aqueous solutions was assessed and compared with pure ILs and alkanolamine solvents, which indicates the solutions studied in this research as better hybrid solvents in terms of CO2 loading. Furthermore, a semi empirical model is used to correlate the solubility data of this work, which presents a good agreement with an absolute average deviation (AAD %) of below 1%.

One of the intriguing properties of clay minerals is swelling, which is considered an essential characteristic for various geological processes, environmental science, and engineering. Almost all previous experimental and simulation studies focused on the understanding of the swelling behavior of pure clays. The fact is that about 30 percent of all clays are a pure type, and virtually 70 percent of clays are the mixed-layer one that swelling mechanism is still elusive. In this research, molecular dynamics simulations were used to exclusively investigate the effect of layer charge distribution on the crystalline swelling and hydration behavior of the most common types of mixed clays, so-called illite-montmorillonite mixed-layer clay (I-Mt MLC) with Na+ and K+ counterions in the presence of different water concentrations. Based on the results, we found that the layer charge density and charge location of both illite and Mt significantly influenced the I-Mt clays' swelling behavior. Regardless of Mt charge density, the presence of highly charged illite led to powerful interactions of counterions with the surface sheet, resulting in less swelling behavior of the I-Mt system. Also, the various polarization power of clay surface due to the difference in charge distribution of octahedral sheets had a significant influence on water molecules and interlayer cations interaction with clay surface, which affected the swelling behavior of I-Mt clays. Overall, our findings demonstrated the new insight into I-Mt clays' swelling behavior, which is a function of charge distribution of both illite and Mt.

The dye with strong two photon absorption (2PA) at low concentration has application in Photodynamic therapy. For this reason, the nonlinear optical properties of Rose Bengal in various solvents, water-surfactant solution and water-in-ionic liquid microemulsion (MEs) was studied by Z-scan technique with a CW Diode laser at 532 nm wavelength and 50 mW power to study the effect of environment on Rose Bengal (RB). The dipole moment of RB in MEs was determined by using a spectrophotometer and fluorometer and the quantum perturbation theory. The results disclose that the nonlinear refractive index and 2PA of RB reduce with the increase of dielectric constant of the medium. Moreover, the NLO properties and dipole moment of RB depend on the formation of anionic surfactant and MEs.

In this research, absorption of CO2 in different ionic liquids (ILs) is studied. Thus four ILs were synthesized containing 1-butyl-3-methylimidazolium as the cation and nitrate [NO3]−, thiocyanate [SCN]−, dicyanamide [N(CN)2]− and hydrogen sulfate [HSO4]− as the anions, respectively. The resulting ILs were then immobilized into activated silica support in a 1/1 IL/SiO2 weight ratio via the impregnation-vaporization method. CO2 sorption behavior of both neat and silica supported ILs (ILs-SiO2) were investigated at different temperatures and flow rates under atmospheric pressure, while their desorption process were carried out under 20 mm Hg at 70 °C. In both sorbents, the best results were obtained at 25 °C with a flow rate of 12 mL/min, where [bmim][N(CN)2] with 1.85 (wt%) or 0.42 mmol CO2 per gram of sorbent and [bmim][HSO4]-SiO2 with 2.33 (wt%) or 0.53 mmol CO2 per gram of sorbent showed the highest sorption capacities. The effect of water on CO2 absorption capacity of the neat and silica supported ILs were also studied by transmission of CO2 gas flue containing 400 ppm water. The results indicated that the mass gain was higher when wet CO2 was passed through the sorbents, opposed to passing dry CO2. Because of the existence of a weak coulombic intraction between the sorbents and CO2, desorption occurs rapidly and a readily reuse of the sorbents is therefore provided.

Low salinity/Smart water injection (LSWI) is a promising enhanced oil recovery (EOR) method, where manipulating the injected water compositions helps in recovery from oil reservoirs via alteration of the rock wettability towards a more water-wet state. In this paper, the experimental data of LSWI in a carbonate core sample have been simulated and matched. The experimental results of oil recovery by injection of four different waters were examined, and the relative permeability curves were adjusted using a dynamic wettability alteration approach. Moreover, results of drainage and imbibition tests used to approximate the corresponding capillary pressures. True effective mobility (TEM) functions were also derived to evaluate the two-phase flow characteristics of the systems. Relative permeability and capillary pressure parameters showed strong correspondence with the injected salinity, and correlations were proposed for estimating the unknown parameters in other similar studies with different salinities. The trend of wettability alteration by LSWI was investigated, and it was concluded that the wettability does not linearly change with salinity, but rather it is non-linearly correlated with the logarithm of the total injected salinity. Injection of seawater (SW) did not significantly change the wettability and flow efficiency of the system compared to formation water (FW). However, dilution of SW to the salinity of 5000 ppm seemed to be the critical threshold below which the effect of LSWI had become substantially more pronounced. The results of this study can be helpful in optimizing and upscaling similar smart water applications, predicting the wettability-related parameters and two-phase flow characteristics at different injected salinities, and also block-to-block modelling in which the effect of the capillary pressure in the fracture network is also considered. Additionally, the non-linear relationship of the wettability-related parameters with salinity is particularly considerable for modifying the common modelling approaches of wettability alteration by LSWI in commercial simulators.

In this paper, inorganic zinc oxide nanoparticles (ZnO NPs) were synthesized through co-precipitation method and after evaluating their physicochemical properties by using TEM and XRD techniques, the bio-thermodynamic and structural parameters upon interaction of ZnO NPs with human serum albumin (HSA) were determined by using fluorescence, UV–vis, CD and molecular docking studies. Also, the selective anticancer effects of ZnO NPs on leukemia (K562) cells were explored by using different cellular and molecular assays. It was determined that the crystalline structure of ZnO NPs has a diameter of about 30 nm. Thermodynamic parameters and docking analysis indicated that the hydrophobic forces mediate the formation of static complex between ZnO NPs and HSA molecules. UV–vis and CD spectroscopic methods showed that the melting temperature (Tm) and secondary structure of HSA, respectively remain substantially unchanged by increase of ZnO NPs. Anticancer assays demonstrated that ZnO NPs trigger an inhibitory impact on the proliferation of K562 cells while being safe against lymphocyte normal cells. Exposure of K562 cells to ZnO NPs resulted in membrane leakage, activation of caspase-9, -3, overexpression of Bax/Bcl-2 mRNA ratio, increase in the level of ROS, cell cycle arrest, and apoptosis/necrosis. In conclusion, it may be suggested that ZnO NPs can be utilized as potential agents in the development of anticancer platforms.

Production of oil from carbonate reservoirs has always been challenging. The nature of these reservoirs is complex and heterogeneous, and the rock matrix often has low permeability and unfavorable wettability. Hence, waterflooding as the primary method for enhanced oil recovery (EOR) usually results in low recovery in non-water-wet carbonate reservoirs. Alternatively, low salinity/Smart water injection (LSWI) has attracted considerable attention and is widely used for recovery improvement in carbonate rocks. Wettability alteration is believed to be the cause of incremental oil recovery during LSWI in carbonates through two main mechanisms of surface charge change and rock dissolution. In this study, the experimental data of smart water coreflooding of a carbonate rock sample from a real oil field was simulated, focusing on geochemical reactions and dynamic wettability alteration. The contribution of different mechanisms was investigated through careful ionic analysis at elevated temperatures. Oil recoveries from the injection of four brines with different salinities were matched, and the ionic compositions of the effluents were studied individually. Acceptable history match was achieved between the experimental and geochemically simulated concentrations. The trends for Ca2+ and Mg2+ concentrations indicated the presence of Calcite and Dolomite dissolution in all cases. In the case of seawater injection, Ca2+ was underestimated while Mg2+ was overestimated, which shows the dominance of Calcite dissolution in higher salinities. As the salinity was reduced to 5000 ppm, the experimental and simulated Mg2+ concentrations became close, which was translated to higher contribution of Dolomite dissolution. By decreasing the salinity to 2000 ppm, a decreasing trend in the SO42− concentration was observed along with overestimation of Mg2+, which showed the contribution of the surface charge change mechanism in lower salinities. According to the results, the proposed mechanism for wettability alteration was therefore concluded to be mainly mineral dissolution, with a contribution of surface charge change at lower salinities. Moreover, the time effect of LSWI on wettability alteration was also observed. This study provides a simulation approach in which, both practical and fundamental (mechanistic) aspects of LSWI are considered. The findings of this study can help for better understanding of the underlying mechanisms during LSWI and their contributions at reservoir temperatures. Furthermore, by using a systematic set of simulations based on the geochemical ionic analysis, optimal conditions for injection water composition could be provided for maximizing recovery during LSWI operations, without the need for numerous, expensive, and tedious laboratory experiments.

Nanoparticles (NPs) have been widely used as anticancer and antibacterial agents. However, before their use in biomedical applications, some in vitro assays should be carried out to investigate their interaction with biological systems. The copper oxide NPs (CuO NPs) were synthesized by hydrothermal method and their interaction with human serum albumin (HSA), leukemia K562 cells and three strains of bacteria was explored by spectroscopic, docking, cellular, and antibacterial investigations. The TEM, DLS, XRD, FTIR, Raman, and UV–visible techniques revealed that synthesized CuO NPs provide a crystalline structure corresponding to CuO nanoclusters with good colloidal stability. Biothermodynamic studies showed that CuO NPs formed a static complex with HSA molecules through hydrogen bonds which was further confirmed by docking analysis. UV–Vis spectroscopy results exhibited that the melting temperature (Tm) of HSA was slightly changed in the presence of CuO NPs. Cellular studies displayed that CuO NPs selectively resulted in the mortality of K562 cells through cell membrane leakage, caspase-9 and -3 activation, and apoptosis. Finally, antibacterial assays depicted that CuO NPs can induce an inhibitory effect in the case of both Gram-negative and Gram-positive bacteria. In conclusion, this study may provide useful data regarding the protein binding and biomedical applications of NPs.

Surfactant flooding has emerged as an interesting enhanced oil recovery (EOR) process due to wettability alteration and reduction of oil-water interfacial tension (IFT). Environmental concerns and high cost, cause synthetic surfactant flooding to become expensive and uneconomical in some circumstances. Natural surfactants are environment-friendly and less expensive than synthetic surfactants which recently have been proposed as alternatives for synthetic surfactants in EOR processes. However, the exact mechanism behind natural surfactant flooding as EOR process is an unsettled and complex issue that has not been completely understood. In this communication, the use of natural surfactants as an alternative for synthetic surfactants for wettability alteration of oil-wet rocks in EOR processes was investigated. Through the wide range of experiments, the performance of a natural surfactant named Cedar in the wettability alteration of carbonate and sandstone rocks was deeply studied. Moreover the effect of natural surfactant on oil-water interfacial tension was compared with common used synthetic surfactants. The results showed that Cedar is very efficient in wettability alteration of both carbonate and sandstone rocks and its effect is comparable with common used synthetic surfactants. In addition, it was found that the cationic surfactant is more effective than anionic surfactants in wettability alteration of carbonate reservoirs. On the other hand, the anionic surfactants are very effective in sandstone rocks. In addition, two distinct trends were observed for wettability alteration of surfactants at different salt concentrations. When the head of surfactant and rock surface carries the same charge, there is an optimum salinity for wettability alteration. Finally, the core flooding experiments demonstrated that natural surfactant can increase oil recovery efficiently.

Antimicrobial and anti-adhesive properties of broad range of 1-Butyl-3-methylimidazolium ionic liquids (ILs) were investigated in our previous work. Since the biological properties of ILs have been one of the most highly debated topics and because of low information on the biological behavior of ILs, a supplementary study was performed to find antibacterial and anti-adhesive activity of many other important ILs. Therefore, imidazolium and pyridinium based ionic liquids including [HMIM][I], [HMIM][PF 6 ], [HMIM][Cl], [HMIM][BF 4 ], [HMIM][NTF 2 ], [HMIM][PTS], [HDMIM][BF 4 ], [HMIM][NO 3 ], [HPY][NO 3 ], [BPY][NO 3 ], [OMIM][NO 3 ] and [BMIM][NO 3 ] were selected for this study. Antibacterial and anti-adhesive activities of these ILs were evaluated against a wide range of pathogenic bacteria namely Staphylococcus aureus , Klebsiella pneumoniae , Salmonella typhimurium , Pseudomonas aeruginosa , Escherichia coli , Bacillus tequilensis and Bacillus subtilis . Agar disk diffusion, agar well diffusion and minimum inhibitory concentration (MIC) analyses as well as minimum bactericidal concentration (MBC) were used for determination of antimicrobial activity. Anti-adhesive activity was investigated by 96 well microtiter plate assay. All the ionic liquids showed antibacterial activity against mentioned microorganism. However, [OMIM][NO 3 ] showed the strongest antibacterial activity because of its long alkyl chain length. Among 1-Hexyl-3-methylimidazolium based ILs, [HMIM][NO 3 ] presented the best antibacterial activity. [HPY][NO 3 ] was on the other hand the strongest growth inhibitor among pyridinium based ILs. In addition, the result of the anti-adhesive activity showed that although [HPY][NO 3 ] exhibited the best anti-adhesive activity, not all ionic liquids have anti-adhesive activity.