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In this study, a novel, cost-effective, and environmental-friendly acetylcholinesterase (AChE)-based electrochemical biosensor was developed and utilized for paraoxon-ethyl (PE) detection. In this biosensor, cerium oxide (CeO2) and poly(3,4 ethylenedioxythiophene):poly(styrenesulfonate) (PESOT:PSS) modified paper electrode was fabricated by a simple dip-coating method. The synergistic effect of CeO2 and PEDOT:PSS enhance the performance of AChE-based biosensor in terms of sensitivity and selectivity. The electrical conductivity and stability of the fabricated electrode are further improved with the treatment of ethylene glycol (EG). EG decreases the coulombic interactions between PEDOT and PSS molecules, causes polymer chain reorientation, and improves the non-covalent interaction between cellulose molecules and PEDOT, which further leads to higher conductivity. All electrochemical results validate that the biosensor shows good selectivity (Kselectivity < 1), high sensitivity of 52.10 µA/nM, and a low detection limit of 0.12 nM. The accuracy and applicability of the proposed biosensor were also checked with two real samples. All results validate that the fabricated paper electrode can be a promising alternative to other conventional electrodes. [ABSTRACT FROM AUTHOR]

A highly sensitive, flexible, cheap, and biodegradable biosensor has been fabricated to detect paraoxon-ethyl (PE) more effectively. In this work, copper oxide (CuO) and poly(3,4-ethylenedioxythiophene):poly(4-styrenesulfonate) (PEDOT:PSS)-modified Whatman paper (WP)-based electrode are fabricated and then characterized by using different techniques. For the fabrication of CuO@PEDOT:PSS/WP electrode, firstly, the PEDOT:PSS/WP was optimized by various solvents such as ethylene glycol (EG), 1-methyl-2-pyrrolidone (NMP), dimethylformamide (DMF), N,N-dimethyl acetamide (NMA), and glycerol to enhance the conductivity. The EG-treated PEDOT:PSS/WP electrode shows maximum conductivity (1.4 × 10− 2 S cm− 1) among all solvents. Further, the incorporation of CuO enhances the electrochemical performance of proposed biosensor. All electrochemical results validate that the proposed biosensor (AChE/CuO@PEDOT:PSS/WP) shows high sensitivity and low detection limit of 9.1279 µA/nM and 0.42 nM, respectively. The proposed paper electrode can be a highly promising alternative to conventional electrodes that are known to have limited applications due to their high cost and limited flexibility. The accuracy of the proposed biosensor was successfully checked in two real samples, which makes it more applicable for PE detection in real-world scenarios. [ABSTRACT FROM AUTHOR]

In this elucidation, we synthesized novel molecularly imprinted polymers (MIPOH1-4) that were used as organic fillers on bagasse pulp to form cellulosic paper sheets, the formation of MIPOH1-4 from the reaction of enaminone 3 with methyl methacrylate monomer in the presence of ethylene glycol dimethyl acrylate and 2,2'-azobisisobutyronitrile. The obtained MIPOH1-4 was confirmed via FT-IR and SEM with different pore sizes. And we noticed that the increase of template 3 increases the hydrogen bond between monomer and template and gave sponge surface of MIPOH4. Furthermore, the computational energies of the template with different monomers utilize DFT/B3LYP/6-31G (d) level to know the stability of polymers and hydrogen bonding between them. So that we applied that in paper manufacture through the adsorption of MIPOH4 as an organic filler on bagasse pulp to form novel cellulosic paper sheets with different concentrations and these sheets which characteristic through FT-IR, SEM, sizing test, tensile strength, and elucidation their antimicrobial activity with theoretical and docking studies. The MIPOH4 and cellulosic paper sheets showed the thermal stability and high tendency of sizability of these paper sheets and concluded the interaction between cellulose fibers of pulp with MIPOH polymer with physical hydrogen bonding. [ABSTRACT FROM AUTHOR]

A novel pressure-sensitive adhesive containing carboxymethyl starch (CMS) with various degrees of substitution, has been developed for the paper industry. Obtained adhesives were transferred onto water-dispersible paper carrier giving repulpable double-sided splicing tape. The effect of carboxymethyl starch degree of substitution (DS) on essential adhesive properties: tack, peel adhesion, as well as shear strength for steel and various papers have been tested. Additionally, the solubility in water and alkaline medium has been evaluated. The highest tack and peel adhesion increase was reported for PSA containing CMS with degree of substitution DS 0.86, to fax paper. Moreover, the dynamic shear strength test, imitating the shear conditions in paper processing revealed, that the highest values of this parameter exhibited the system with 15 wt% CMS DS 0.86. For this system, the shortest water-dissolving times as well as at elevated pH were noted: 314 s and 60 s, respectively. The best performance exhibited the adhesive prepared from the mixture of acrylic monomers (35 wt% 2-ethylhyexyl acrylate, 30 wt% butyl acrylate and 35 wt% acrylic acid), 0.4 wt% aluminum acetyl acetonate (crosslinking agent), 50 wt% poly(ethylene glycol) as plasticizer, and 15 wt% CMS with DS 0.86 (basing on acrylic polymer content). [ABSTRACT FROM AUTHOR]

The possibilities of application of carbonized paper (CP) for preparation of carbon-containing material modified with various electroactive compounds and composites both in the acidic and alkaline media are studied. It is shown that carbonized paper is an adequate substrate for the electrochemical synthesis of poly- o-phenylenediamine electroactive polymer, nickel oxygen compounds from nickel sulfonated phthalocyanine (NiTsPc), as well as for the chemisorption of silicododecamolybdic acid (SiMo). It is shown that CP modified with nickel compounds can be used as the catalyst for the electrooxidation of ethylene glycol (EG). [ABSTRACT FROM AUTHOR]

A fluorometric method based on molecularly imprinted upconversion fluorescence test strip was developed for the determination of tyramine. It exploited the green fluorescence of upconversion nanoparticles (UCNPs) and the specific recognition property of molecularly imprinted polymers (MIPs). UCNPs were attached to filter paper with glue, and MIPs were prepared via in situ polymerization on the surface of UCNPs by using tyramine as template, methacrylic acid as functional monomer, and ethylene glycol dimethacrylate as cross-linker. The green fluorescence of the test strip, with excitation/emission wavelength 980/550 nm, was enhanced by tyramine. The test strip was suitable for the determination of tyramine in the linear range 1.0–100.0 mg L−1, and a relatively low limit of detection (0.2 mg L−1) was achieved. The test strip also worked well for the quantitation of tyramine in spiked red wine and mature vinegar. Recoveries are ranged from 84.9 to 99.9%. The relative standard deviations are below 5.6%. [ABSTRACT FROM AUTHOR]

In order to use carbon nanotube (CNT)-supported catalyst as fuel cell electrodes, Pt-Ni-Fe/CNT/carbon paper (CP) electrode was prepared using an ethylene glycol reduction method. CNTs were directly synthesized on Ni-impregnated carbon paper, plain carbon cloth, and Teflonized carbon cloth using chemical vapor deposition. FESEM and TEM images and thermogravimetric analysis indicated that in situ CNT on carbon paper (ICNT/CP) possesses more appropriate structural quality and stronger adhesion to the substrate than other substrates. The contact angle analysis demonstrated that the degree of ICNT/CP surface hydrophobicity encountered a 24% increase in comparison to CP and promoted to superhydrophobicity from hydrophobicity. The polarization curves and electrochemical impedance spectroscopy results of the loaded Pt-Ni-Fe on in situ and ex situ CNT/CP illustrated that the power density increased and charge transfer resistance reduced compared to commercial Pt/C loaded on CP. The results can be attributed to the outstanding properties of CNTs and high catalytic activity of triple catalysts causing alloying of Pt with Ni and Fe, which makes them a proper candidate to be used as cathode electrodes in proton exchange membrane fuel cells. [ABSTRACT FROM AUTHOR]

In search of strategies to operate photochromic compounds in aqueous environments, we synthesized two oxazines with a pendant oligo(ethylene glycol) chain each and a co-polymer with multiple oxazine and oligo(ethylene glycol) tails appended to a common macromolecular backbone. The hydrophilic character of the oligo(ethylene glycol) chains imposes solubility in water on two of the three systems. Their laser excitation in water opens the oxazine ring in less than 6 ns to generate zwitterionic isomers able to absorb in the visible region of the electromagnetic spectrum. The photogenerated species revert spontaneously back to the original forms with first-order kinetics. The transition from organic solvents to aqueous environments, however, causes a five-fold decrease in the quantum yield of the photoinduced ring-opening process and elongates the lifetime of the photogenerated isomer from the nanosecond to the microsecond domain. These hydrophilic and photochromic switches can be interconverted hundreds of times between their two states with no sign of degradation in water. As a result, our structural design for the realization of water-soluble photochromic compounds can lead to the development of viable strategies to modulate the structures and functions of biomolecules with microsecond switching times and excellent fatigue resistances under the influence of optical stimulation. [ABSTRACT FROM AUTHOR]

Inadequate ionic conductivity and freezing of the electrolyte are considered one of the main problems in low-temperature electrochemical energy storage. Mixing two or more solvents can reduce the overall freezing point of the solution and also increase the ionic conductivity at low temperatures. Therefore, using the co-solvent method to prepare electrolytes is crucial for preventing electrolyte freezing and improving ion conductivity. In this paper, ethylene glycol (EG) was used as a low-temperature co-solvent and an electrolyte with a freezing point lower than − 80 ℃ was obtained by the introduction of a volume fraction of 20% ethylene glycol in 4.5 mol L−1 LiCl aqueous solution. The resulting electrolyte exhibited high ionic conductivity (1.143 mS·cm−1) at − 60 ℃ and low viscosity (1.391 mPa·s) at 20 ℃. The molecular dynamics (MD) simulations and FITR results indicate that hydrogen bonds can be effectively formed between ethylene glycol and water molecules, which facilitate the electrolyte to operate at low temperatures. Additionally, the supercapacitor was able to operate better even at − 60 °C by introducing ethylene glycol into the electrolyte. [ABSTRACT FROM AUTHOR]

In this paper, the effect of cross-linking agent on structural, morphological and luminescence properties of Ce-doped Gadolinium–aluminium–gallium garnet (called GAGG:Ce3+) was studied. Monoethylene glycol (EG) and various molecular weights (MWs) of Polyethylene glycol (PEG 400 and 1000) were used as cross-linking agents for sol–gel derived samples which were characterized by differential scanning calorimetry/thermogravimetry (DSC/TG), X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), Fourier transform infrared spectrometry (FTIR) and photoluminescence (PL). XRD analysis showed that GAGG: Ce3+ crystallized in a single stable cubic phase for EG prepared sample and, independently in mixed cubic/perovskite phases for PEG 400 and 1000 prepared samples. FE-SEM investigation indicated a significant influence of the cross-linking agent on the morphology and the size of particles. Largest particles were obtained in PEG 1000 sample with an average size of ~ 414 nm. For PL, the highest emission intensity was observed for EG sample which is ascribed to single cubic phase. However, high luminescence quenching was found in high MWs of PEG samples that can be attributed to the growth of secondary phases, defect generation and high Ce4+ content. The nanogarnet obtained using EG presented a pure stable cubic phase and high luminescence emission making it a potential candidate to serve as an efficient scintillator. [ABSTRACT FROM AUTHOR]

Regarding the increasing production from unconventional reservoirs, especially shale reservoirs, it is essential to determine appropriate drilling fluid in drilling operations to have maximum efficiency. Selective performance of drilling fluids may increase the formation penetration rate and increase the drilling efficiency. This paper compares the three types of drilling fluids to compare their rheological properties and provide the best drilling fluid composition for shale stabilization. This paper can bring reliable experimental results for petroleum industries, especially drilling operations, to reduce the formation damage and shale instabilities in subsurface formations. To perform the tests under the same conditions, the formulation of all samples is the same in terms of both utilized polymers to determine the effect of other compositions in selected drilling fluids. For the silicate drilling fluid, since silicates perform well at higher pH (potential of hydrogen), the pH of the silicate drilling fluid is increased to 11 by the addition of sodium hydroxide (NaOH). The lowest decrease in fluid viscosity is related to silicate fluids, indicating the more excellent thermal stability of these types of drilling fluid than glycol and potassium chloride (KCl). Plastic viscosity (PV) is about 20 cP for silicate drilling fluids, while it has the minimum value for glycol drilling fluids after heating. It is about 7.5 cP. Apparent viscosity (AV) is about 23 cP for silicate drilling fluids, while it has the minimum value for glycol drilling fluids after heating. It is about 11 cP. The yield point (YP) before heating is almost the same for different fluids, but after heating the drilling fluids, the reflux point for silicate and glycol drilling fluids is significantly reduced. The yield point is about 6.5 Ib/100ft2 for silicate drilling fluids, while it has the maximum value for glycol drilling fluids after heating. It is about 8 Ib/100ft2. [ABSTRACT FROM AUTHOR]

The use of water-based chemistry in photolithography during semiconductor fabrication is desirable due to its cost-effectiveness and minimal environmental impact, especially considering the large scale of semiconductor production. Despite these benefits, limited research has reported successful demonstrations of water-based photopatterning, particularly for intrinsically water-soluble materials such as Poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) due to significant challenges in achieving selective dissolution during the developing process. In this paper, we propose a method for the direct patterning of PEDOT:PSS in water by introducing an amphiphilic Poly(ethylene glycol)-block-poly(propylene glycol)-block-poly(ethylene glycol) (PEO-PPO-PEO, P123) block copolymer to the PEDOT:PSS film. The addition of the block copolymer enhances the stretchability of the composite film and reduces the hydrophilicity of the film surface, allowing for water absorption only after UV exposure through a photoinitiated reaction with benzophenone. We apply this technique to fabricate tactile and wearable biosensors, both of which benefit from the mechanical stretchability and transparency of PEDOT:PSS. Our method represents a promising solution for water-based photopatterning of hydrophilic materials, with potential for wider applications in semiconductor fabrication. [ABSTRACT FROM AUTHOR]

Heart disease-related deaths have increased in recent decades, with most patients dying of sudden cardiac arrest. In such instances, the effect of regular electrocardiogram (ECG) measurements is minimal. Therefore, long-term ECG monitoring has become increasingly important. In this paper, we report a non-adhesive high accuracy ECG monitoring system that can be used in various scenarios without interfering with daily activities. The ECG ultra-thin film electrode is made by water-resistant material based on poly(3,4-ethylenedioxythiophene) poly(4-styrenesulfonate) (PEDOT: PSS) electrode doped with ethylene glycol (EG) and xylitol, to improve the noise signal caused by sweat. The optimal ratio of the three ingredients of PEDOT: PSS/xylitol/EG was determined experimentally to accommodate the ECG monitoring. By using the proposed selectively closed multi-channel single-lead logic circuit, the noise of ECG signal received from the proposed film electrode can be successfully reduced during broad-area electrode measurements, thus to improve ECG measurement accuracy. [ABSTRACT FROM AUTHOR]

Inkjet printing technology holds a great potential for fabrication of biosensor device. An optimized programmed printing makes the processing steps easier on a variety of substrates at low cost. The drop-on-demand piezoelectric mode of printing can construct a design pattern with low volume of material at specified position onto a suitable substrate. But to achieve this successfully, a formation of stable ink suspension remains the most challenging task. In recent times, nanoparticles are considered to pave a way for miniaturization of biosensing devices. Thus, we synthesized, characterized and investigated the stability of magnetic Fe3O4 nanoparticles stabilized by the polyamidoamine (PAMAM = N(CH2CH2C(O)NHCH2CH2NH2)(CH2CH2N(CH2CH2C(O)NHCH2CH2NH2)2)2) dendrimer (PAMAM@Fe3O4). A best stable ink dispersion of PAMAM@Fe3O4 nanoparticles was obtained in a solvent mixture of 70% ethylene glycol and 30% distilled water. The nanoparticle ink with surface tension of 57.47 mN/m and viscosity of 5.45 mPa/s formed a narrow and uniform printed pattern onto graphene paper. Further, as a model protein for future biosensing application, antibody against alpha-fetoprotein was conjugated onto the dendritic surface and printed onto graphene paper. The characterization of the printed pattern by TEM revealed spherical morphology, whereas SEM provided evidence of difference in printed line width and spacing of nanoparticles and antibody conjugated nanoparticles. As a proof-of-concept, the study demonstrated a printable ink dispersion based on PAMAM@Fe3O4 nanoparticles for future miniaturization of biosensing steps on a chip-based platform. [ABSTRACT FROM AUTHOR]

This paper reports the results of an experimental investigation of graphene particle suspensions in lubricating oil, ethylene glycol and glycerol-based fluids. Graphene particles of different specific surface area show variation in the viscosity depending on the shear rate and the temperature. The lubricating effect, e.g., reduction in the viscosity compared to the base fluid, is observed for the concentration (below 0.4 mass%) in lubricating oil and glycerol. In the range of parameters studied (e.g., concentration below 1 mass% and temperature up to 80 °C), the activation energy slightly decreases. The enhancement of viscosity with graphene volume fraction is larger for ethylene glycol. [ABSTRACT FROM AUTHOR]

For the outside cabin heat exchanger of wind power generation, the overall numerical simulation plays an important role in its design and optimization. The periodic iterative simulation method proposed in this paper makes up for the deficiency of analogy research using the local model in the previous research of plate-fin heat exchanger so that the research conclusions can be directly applied to practical engineering. The effectiveness of this method is verified by comparing 10 groups of simulation results with experimental results. It is concluded that the maximum relative error of the periodic iterative simulation method is 0.9%, which meets the requirements of engineering calculation. The number of iterations can be reduced to two when only the outlet average temperature is involved, which is more convenient than the dozens of iterations. Furthermore, the effects of altitude, air velocity, air temperature, wave fin structure parameters, and generator power on the performance of heat exchanger are comprehensively analyzed. The results show that larger naturally captured air volume, lower ambient temperature, and lower altitude can effectively reduce the outlet temperature of ethylene glycol solution. When the amplitude and wavelength of the corrugated fin on the airside of the heat exchanger are 0.6 mm and 20 mm respectively, the naturally captured air volume is effectively increased, the overall heat exchange performance of the heat exchanger is further improved. [ABSTRACT FROM AUTHOR]

Due to their strong antibacterial activity and nanometric size, nanoparticles have become a feasible option for a range of medical treatments. The purpose of the research is to prepare a nanocomposite of four materials, and to study the effect of the content of silicon dioxide (SiO2) / cobalt oxide (CO2O3) NPs on the PVA–PEG mixture. In this paper, samples of polymer nanocomposite were created by solution casting. The test specimens were made of an organic host matrix consisting of poly (ethylene glycol) (PEG) and poly (vinyl alcohol) (PVA) polymer mixture. Different concentrations of silicon dioxide (SiO2) and cobalt oxide (CO2O3) were introduced to specimens at different weight percentages (0%, 2%, 4%, 6%, and 8%). The present research tested the optical, structural, morphological, and antibacterial characteristics of (PVA–PEG-SiO2–CO2O3) NCs. The blended homogenous nanoparticle distribution, which forms a unified network across the polymer matrix, is shown in the optical microscope photos. The outcomes of field emission scanning electron microscope (FE-SEM) investigations show that the surface morphology is sufficiently homogenous and distributed. The blend consisting of polyvinyl alcohol (PVA) and (polyethylene glycol) (PEG) was discovered to be amorphous by X-ray diffraction (XRD) investigation. Furthermore, peaks of other nanomaterials appeared at all nanocomposites sample concentrations, and we compared them with the reference code PDF. For both allowed and forbidden transitions, the energy gap shrinks from (4.23 to 3.22) eV and (3.9 to 2.59) eV, respectively. The outcomes indicate an upward trend between the measured absorbance values, absorption coefficient (α), refractive index (n), real and imaginary dielectric constants, and optical conductivity (σop) with riesing the concentrations of (SiO2–CO2O3) nanoparticles, especially in the UV and visible areas. It appeared clearly at the highest amount of nanoparticles at a certain wavelength (390 nm), and the results indicated that they could be attractive materials for nano-oriented optoelectronic devices. The antibacterial properties of the (PVA–PEG-SiO2–CO2O3) nanocomposites were finally studied. As the ratio of SiO2–CO2O3 nanoparticles to PVA-PEG grew, so did the antibacterial activity of S. aureus and E. coli, yielding inhibition region values of (20 and 21) mm, respectively. Accordingly, this study's results show how useful and viable nanocomposites are for use in the optical electronics, and medical industries. [ABSTRACT FROM AUTHOR]

The paper describes examples of microemulsions based on a well-known biocompatible surfactant, lecithin, and the possibilities of their use as drug carriers. The main problem encountered when developing lecithin microemulsions is the search for suitable cosurfactants. Molecules with short alkyl chains (4–5 C atoms) and relatively large polar "head," such as short-chain aliphatic alcohols, acids, and amines are most suitable as cosurfactants for the preparation of lecithin microemulsions. Therewith, high concentrations of the cosurfactants (the cosurfactant : lecithin weight ratio usually is 1 : 1) are necessary. Most often, ethanol, n-propanol, or n-butanol are used as cosurfactants for the preparation of lecithin microemulsions in various natural and synthetic oils. To replace toxic alcohols with less toxic components, other well-known surfactants may be added to lecithin microemulsions. They are, e.g., Brij 96V (poly(ethylene glycol) oleate), Tween 80 (polyoxyethylene-20-sorbitan monooleate), Tween 20 (polyoxyethylene-20-sorbitan monolaurate). Triton X-100 (tert-octylphenyl ether of poly(ethylene glycol)) or oleic acid. Composites based on lecithin microemulsions have been described as means for local anesthesia and delivery of vitamins, as well as agents with anti-inflammatory, antifungal, anticancer, and wound healing effects. The considered examples show the promise of the study and development of lecithin microemulsions as drug carriers. [ABSTRACT FROM AUTHOR]

Coal to ethylene glycol still lacks algorithm optimization achievements for distillation sequencing due to high-dimension and strong nonconvexity characteristics, although there are numerous reports on horizontal comparisons and process revamping. This scenario triggers the navigation in this paper into the simultaneous optimization of parameters and heat integration of the coal to ethylene glycol distillation scheme and double-effect superstructure by the self-adapting dynamic differential evolution algorithm. To mitigate the influence of the strong nonconvexity, a redistribution strategy is adopted that forcibly expands the population search domain by exerting external influence and then shrinks it again to judge the global optimal solution. After two redistributive operations under the parallel framework, the total annual cost and CO2 emissions are 0.61%/1.85% better for the optimized process and 3.74%/14.84% better for the superstructure than the sequential optimization. However, the thermodynamic efficiency of sequential optimization is 11.63% and 10.34% higher than that of simultaneous optimization. This study discloses the unexpected great energy-saving potential for the coal to ethylene glycol process that has long been unknown, as well as the strong ability of the self-adapting dynamic differential evolution algorithm to optimize processes described by the high-dimensional mathematical model. [ABSTRACT FROM AUTHOR]

This paper analyzes heat transfer mechanisms in a compound parabolic concentrator solar collector by demonstrating a new thermal resistance network. Present study developed an analytical thermal model based on nanofluids. In addition, experimental data in similar conditions have been applied to validate and increase the reliability of the model. A laminar flow in the Reynolds number range of 726 to 1827 flows through the absorbent tube. The results were examined in four volumetric flow rates of 1, 1.5, 2, 2.5 L min−1 and three concentrations of the SiO2/ethylene glycol–Water nanofluid with 0.5%, 1% and 1.5% volumetric fractions. The results revealed that the developed thermal model with an error percentage of less than 6% for the nanofluid was in good agreement with the experimental data. The mean error of the temperature difference between the thermal modeling and empirical data was estimated at 4.61%. Furthermore, the analysis pointed out that the increase in pumping power was less than 3.65%, whereas the thermal efficiency enhancement was up to 10.43% in the highest volumetric fraction of nanofluid. Since the thermal model is based on applying physical laws, it could be applied to other heat transfer fluids in various operative and environmental conditions. Likewise, the presented thermal model is a secure tool for designing and optimizing as well as controlling different energy parameters in compound parabolic concentrators. [ABSTRACT FROM AUTHOR]

In recently years, polyol prepared from biobased renewable resources has attracted researchers' attention to synthesize green environmental polyurethane. Among numerous polyols, poly (trimethylene ether glycol) (PO3G) is used to prepare polyurethane due to outstanding performances. This paper aims to prepare photosensitive polyurethane acrylate based on 100% renewable PO3G with low viscosity, great flexibility and fast curing speed. The physical and thermal properties of materials were characterized by FTIR, ATR, DSC and DMA. The mechanical properties were measured emphatically. All the results suggest the prepared PO3G-based resins exhibit excellent strength and flexibility with low viscosity. On the other hand, the blocking agent with dynamic covalent bond was introduced to ensure the low viscosity of resins under UV curing. With the break of blocking agent, the isocyanate group could be fully released and carry out chain extension with amine during secondary curing to form polyurethane network and comprehensive performance of resins. Furthermore, the prepared materials have significant advantage and show good application potential in UV-curing 3D printing. [ABSTRACT FROM AUTHOR]

Artificial calcium oxalate films have been applied to protect sculptures, monuments, and buildings made of marble due to their potential protective capacities. Unfortunately, artificially prepared calcium oxalate films are usually loose, and easy to peel off in contrast to the natural ones. In this paper, a new method was developed for the preparation of a compact and cohesive calcium oxalate film, using ethylene glycol as an additive. The morphology, elemental composition, structure, and crystal phase of the film were analyzed by SEM, EDX, IR, and XRD, and the protective effects were investigated by acid resistance test, while its adhesion to the underlying marble by the Scotch tape test. The porosity, water absorption, and color of treated marble were also assessed. The results showed that a calcium oxalate film with a compact structure, good adhesion, and a protective effect against acid rain can be successfully obtained by including ethylene glycol as an additive. With the new preparation method, a better bond between the stone and the film is obtained which contributes to solving the spalling problem of the artificial calcium oxalate films. [ABSTRACT FROM AUTHOR]

In this paper, the results of the experimental study on density, surface tension and optical properties of ethylene glycol-based nanofluids containing silicon dioxide have been presented. The nanofluid-air surface tension values were determined in the temperature range from 283.15 K to 318.15 K with Du Noüy ring method with the commercial equipment and self-made station. To determine the surface tension of a fluid, the information about its density is required; therefore, density of all examined nanofluids was measured in the same temperature range, and results were summarized in the paper. The refractive index of SiO 2 -EG nanofluids was determined in the same temperature range in which the surface tension was examined. Finally, the extinction (UV–Vis spectra) of these materials was examined and presented. [ABSTRACT FROM AUTHOR]

The synthesis of polymeric nanoparticles (NPs) with efficient drug loading content and targeting moieties is an attractive field and remains a challenge in drug delivery systems. Atomistic investigations can provide an in-depth understanding of delivery devices and reduce the number of expensive experiments. In this paper, we studied the self-assembly of poly (lactic-co-glycolic acid)-b-poly (ethylene glycol) with different molecular weights and surface compositions. The innovation of this molecular study is the loading of an antitumor drug (docetaxel) on a targeting ligand (riboflavin). According to this work, a novel, biocompatible and targeted system for cancer treatment has been developed. The obtained results revealed a correlation between polymer molecular weight and the stability of particles. In this line, samples including 20 and 10 w/w% moiety NPs formed from polymers with 3 and 4.5 kDa backbone sizes, respectively, are the stable models with the highest drug loading and entrapment efficiencies. Next, we evaluated NP morphology and found that NPs have a core/shell structure consisting of a hydrophobic core with a shell of poly (ethylene glycol) and riboflavin. Interestingly, morphology assessments confirmed that the targeting moiety located on the surface can improve drug delivery to receptors and cancerous cells. The developed models provided significant insight into the structure and morphology of NPs before the synthesis and further analysis of NPs in biological environments. However, in the best cases of this system, Dynamic Light Scattering (DLS) tests were also taken and the results were consistent with the results obtained from All Atom and Coarse Grained simulations. [ABSTRACT FROM AUTHOR]

A new strategy was developed to build a CO2-philic/hydrophilic surfactant by combining the common free radical polymerization and the grafting modification technology, and a brush polymer was synthesized with poly(vinyl acetate)(PVAc) based copolymer as the CO2-philic group (as the main chain) and the methoxy poly(ethylene glycol) (mPEG) as the hydrophilic part (as the branched chain) (PVAc-g-mPEG). The CO2-philic ability can be controlled by adjusting the chain length of the CO2-philic fragment. The results indicate that PVAc-g-mPEG has excellent surfactant activity, and can emulsify the CO2/H2O system to obtain the CO2-in-water (C/W) high interval phase emulsion (HIPE 80%, v/v), which can remain stable for more than 20 h. If using the monomers/crosslinking agent solution instead of water, the highly porous monolithic materials will be obtained after the continuous phase is polymerized. In this paper, polyacrylamide (PAM) and poly(acrylamide/diethyl aminoethyl methacrylate) (PADM)-based porous monolithic materials were prepared. These materials were used to remove bovine serum albumin (BSA, as the model matter) from the solution, and the results indicated that PAM-based porous monolithic materials had almost no enrichment capacity for protein, while PADM-based porous monolithic materials can adsorb BSA up to 129.3 mg/g. [ABSTRACT FROM AUTHOR]

This paper demonstrates the preparation of ZnMn2O4 nanoparticles through thermal hydrolysis in different solvents, such as isopropanol, ethylene glycol, glycerol, and water, combined with pyrolysis. The obtained samples were characterised by using X-ray diffraction (XRD), infrared spectroscopy (FT‒IR), scanning electron microscopy (SEM), energy-dispersive X-ray mapping, nitrogen adsorption/desorption isotherms, and a vibrating sample magnetometer. The electrocatalytic activity of ZnMn2O4 nanoparticles was investigated toward the oxidation of uric acid (UA) and xanthine (XA). The ZnMn2O4-nanoparticle-modified electrode not only enhances the oxidation currents of the two purine derivatives but also successfully separates the voltammetric signals of the analytes in their binary mixture and, hence, is employed for their simultaneous determination. The factors affecting the analysis, such as pH, scan rate, linear range, detection limit, reproducibility, and interferents, were also investigated. The results show that the UA and XA limits of detection are as low as 0.55 and 1.28 µM, and the modified electrodes have satisfactory repeatability and reproducibility. The practical application of the modified electrode was demonstrated by simultaneously determining the concentrations of UA and XA in urine samples with exceptional accuracy. [ABSTRACT FROM AUTHOR]

This paper investigates drug release from a novel series of mPEG-functionalised PLLA polymers whose individual components (PEG and PLLA) have regulatory FDA approval. Two processing methods were explored to understand their effect on the morphology and drug release profiles of the polymers, with and without mPEG functionalisation. In the first method the polymer and Propranolol.HCl drug powders were mixed together before injection moulding. In the second method, supercritical CO2 was used to mix the polymer and drug before injection moulding. When non-functionalised PLLA was processed through injection moulding alone, there were no signs of polymer-drug interaction, and the drug was confined to crystals on the surface. This resulted in up to 85 wt% burst release of propranolol.HCl after one day of incubation. By contrast, injection moulding of mPEG-functionalised polymers resulted in the partial dissolution of drug in the polymer matrix and a smaller burst (50 wt% drug) followed by sustained release. This initial burst release was completely eliminated from the profile of mPEG-functionalised polymers processed via supercritical CO2. The addition of mPEG facilitated the distribution of the drug into the bulk matrix of the polymer. Paired with supercritical CO2 processing, the drug release profile showed a slow, sustained release throughout the 4 months of the study. [ABSTRACT FROM AUTHOR]

In this paper, a novel molecularly imprinted polymer (MIP) for specific adsorption of steviol glycosides was designed, and the imprinting mechanism of self-assembly system between template and monomers was clearly explored. Firstly, steviol (STE) was chosen as dummy template, and the density functional theory (DFT) at B3LYP/6–31 + G (d, p) level was used to select monomers, imprinting molar ratios, solvents, and cross-linking agents. The selectivity to five steviol glycosides was also calculated. Importantly, reduced density gradient (RDG) theory combined with atom in molecules (AIM) and infrared spectrum (IR) was applied to investigate the bonding situation and the nature of noncovalent interaction in self-assembly system. The theoretical designed results showed that the template which interacts with acrylic acid (AA) has the minimum binding energy, and the complex with the molar ratio of 1 : 4 has the most stable structure. Toluene (TL) and ethylene glycol dimethacrylate (EGDMA) were chosen as the optimal solvent and cross-linking agent, respectively. Five hydrogen bonds formed in the self-assembly system are the key forces at the adsorption sites of MIPs through the RDG and AIM analyses. The MIPs were synthesized by theoretical predictions, and the results showed that the maximum adsorption capacity towards dulcoside A is 26.17 mg/g. This work provided a theoretical direction and experimental validation for deeper researches of the MIPs for steviol glycosides. In addition, the method of RDG theory coupled with AIM and IR also could be used to analyze other imprinting formation mechanisms systematically. [ABSTRACT FROM AUTHOR]

The environmental pollution caused by complicated wastewater, such as oily wastewater with various metal ions, is becoming more and more serious, which promotes the rapid development of separation materials and relevant methods. In this paper, poly (vinylimidazole-co-polyethylene glycol diacrylate) (V-co-P) cryogel was synthesized by poly (ethylene glycol) diacrylate and vinylimidazole as monomers via freeze-thawing method, followed by its characterization with SEM, FT-IR, and XPS. It was found that Cu(II) was chemically absorbed on poly (V-co-P) cryogels and the maximum adsorption capacity of the poly (V-co-P) cryogel was determined to be 51.57 mg g−1. More importantly, the poly (V-co-P) cryogel can effectively separate various oil-in-water emulsions containing Cu(II) in one step, and the micron droplets in the emulsion disappeared completely. The efficiency of Cu(II) removal was determined to be more than 97.5%. Moreover, this cryogel could be reused without significant loss of separation performance after ten cycles. In general, the cryogel prepared by simple freezing polymerization shows both heavy metal removal capacity and oil–water separation ability, which offers considerable potential applications on the disposal of complicated wastewater in the environment. [ABSTRACT FROM AUTHOR]

Controls over the dimensions of waterlogged archaeological wood (WAW) upon drying are a critical issue for its conservation. Surface-initiated activator regenerated by electron transfer atom transfer radical polymerization (SI-ARGET ATRP) has been proven to be an effective consolidation method to increase the dimensional stability. However, the drawback of the current method is that the expansion stress generated during graft polymerization cannot be well controlled. An improved SI-ARGET ATRP system using a bifunctional monomer ethylene glycol dimethacrylate (EGDMA) to introduce a cross-linking process during the polymerization is presented in this paper. Both Pinus massoniana and Sapium sp. samples with different maximum moisture contents as 507% and 863%, respectively, show a reduced volumetric shrinkage of around 5% without any expansion phenomenon after the treatment. This method shows potential applications in the field of WAW conservation and may provide a new solution for consolidation of other organic archaeological objects as well as developing new wood-based materials. [ABSTRACT FROM AUTHOR]

The popularization of conventional dimethyl oxalate to ethylene glycol (DMOtEG) has kept ongoing in the past decade in China. Recently, a northern China factory in construction attracts attention using alternative formaldehyde to ethylene glycol (FtEG) route. Thus, a question arises about the individual comparative advantages of these two processes. So, this paper conducts a systematic modeling analysis of DMOtEG and FtEG, and the life cycle assessment is performed by SimaPro v9 to compare their impact. The results indicate the inferiority of life cycle energy consumption and life cycle cost of FtEG to those of DMOtEG due to the high energy consumption and pollutant emissions. Moreover, most impact categories of FtEG are worse than the DMOtEG as global warming, and photochemical oxidant formation potential. Despite this, FtEG still wins for better potentials in ozone formation, fine particulate matter formation, and terrestrial acidification because of less nitride emissions. In addition, the decrease in energy consumption and external cost will significantly decrease the life cycle cost under controllable catalyst costs of FtEG. These results describe the impact categories of DMOtEG and FtEG and provide a basis to help decision-makers develop coal to ethylene glycol processes. [ABSTRACT FROM AUTHOR]

The paper presents the results of an experimental study of the density and surface tension of ethylene glycol-based nanofluids containing zinc oxide, magnesium oxide and indium oxide. Du Noüy ring method was employed to determine the values of the surface tension of these nanofluids. Samples were prepared in various mass fractions from 0.01 to 0.05 with 0.01 step. Examination was performed in the temperature range from 283.15 K up to 318.15 K. The averaged surface tension values for the studied ZnO14-EG, ZnO25-EG, MgO-EG, In 2 O 3 -EG nanofluids at 298.15 K are 48.685, 48.471, 48.335, and 48.462 mN·m - 1 , respectively. It was presented that surface tension value could be consider as constant within the examined mass fraction of the particles, and the explanation of such behaviour was provided. [ABSTRACT FROM AUTHOR]

Cu/SiO2 catalyst prepared by the ammonia-evaporation (AE) method is the potential preferred catalyst for hydrogenation of dimethyl oxalate (DMO) to ethylene glycol (EG). Although significant advancements have been obtained in the confirmation and influence factors of active species in the hydrogenation process, the relationship between the catalytic activity and the sensitive factors in the preparation or pretreatment process of the catalyst is still uncertain. In this paper, Cu/ZSM-5 catalysts for DMO hydrogenation to EG were prepared by the AE method using ZSM-5 molecular sieve with high silicon-alumina ratio (1500) as a support. The ZSM-5 support was pretreated by drying at 393 K for different hours and it was found that the surface hydroxyl group of the support had significant influence on the structure and catalytic hydrogenation performance of the prepared Cu/ZSM-5 catalyst. The distribution of surface hydroxyl groups could be significantly changed by pre-drying the carrier, which further resulted in the change of the copper dispersion and surface properties of subsequent copper-supported catalysts. With the decrease of hydroxyl content on the surface of the ZSM-5 support, the prepared reduced Cu/ZSM-5 catalyst possessed smaller Cu0 particles size, higher copper dispersion, higher surface area of Cu0 and Cu+ species, but weakened surface acidity of the catalyst, which resulted in the great improvement of the catalytic activity. The DMO conversion and EG selectivity could reach 100% and 93% even under the low reaction temperature at 448 K over the Cu/ZSM-5-24 catalyst (based on the ZSM-5 support pretreated by drying for 24 h). In addition, the catalytic activity did not show obvious change after 300 h of reaction, probably due to the low temperature reaction and suitable surface properties of the catalyst. [ABSTRACT FROM AUTHOR]

Detecting living algae from treated ship's ballast water is an important task for port state control (PSC) under the requirement of the International Ballast Water Convention. In this paper, electrokinetic detection and separation of living algae from NaClO- and UV-treated ship's ballast water in a microfluidic chip are presented. The electrokinetic movement of algae in a straight poly ethylene glycol (PEG)–modified PDMS microchannel filled with 10% PEG solution was measured by using an optical microscope. The experimental results show that the moving velocity of dead algae is lower by more than 80% in comparison with living algae. The decreased velocity is larger for larger dead algae and the velocity is decreased to zero for dead algae larger than 6 μm in diameter. A curve was obtained to evaluate the vitality of algae with similar moving velocity but different sizes. Electrokinetic separation of living algae from a mixture sample in a straight channel was also achieved. The method presented in this paper provides a moving velocity–based approach for quickly evaluating the living status of algae in treated ship's ballast water. [ABSTRACT FROM AUTHOR]

The leaching behavior of molybdenite was investigated in H2O2–H2SO4 solution in this paper. The results show that H2O2 was an effective oxidant for molybdenite leaching, but it had fast decomposition kinetics. A final molybdenum extraction of 73.0% was obtained under the experimental conditions of 0.5 mol/L H2SO4, 0.5 mol/L H2O2, and the fresh H2O2 addition enhanced molybdenum extraction from 73.0 to 94.5%. The leaching process was controlled by a mixture of surface reactions and diffusion, and the activation energy was 27.98 kJ/mol. Ethylene glycol enhanced molybdenum extraction and improved the stability of H2O2. Electrochemical studies suggested that the decomposition kinetics of H2O2 was faster than that of molybdenite oxidation, and ethylene glycol enhanced recovery by increasing the resistance of H2O2 decomposition and decreasing the resistance of molybdenite oxidation. XRD and XPS analysis confirmed that ethylene glycol did not alter the phase composition and the surface chemical statues of molybdenite. [ABSTRACT FROM AUTHOR]

Organic phase change materials (PCMs) are inexpensive, safe, and do not segregate. However, they exhibit a low thermal conductivity. Several papers have reported the synthesis of organic–inorganic hybrid PCMs by adding inorganic fillers to increase the thermal conductivity. However, large amounts of fillers are needed to support the shape for the encapsulation of PCMs. Herein, we propose a facile synthesis strategy that yields composite PCMs with enhanced thermal performance. Initially, 1,3:2,4-dibenzylidene sorbitol (DBS) organogel was added as an organic filler to poly(ethylene glycol) (PEG) PCMs for maintaining the form and prevent leakage. Subsequently, a small amount of an inorganic filler, graphene nanoplatelets (GNPs), was added to these organic PCMs. Consequently, the thermal conductivity and shape stabilization of the PEG/GNPs/DBS PCMs were significantly improved. These prepared composite PCMs, with excellent shape stabilization, appropriate latent heat, and ideal thermal conductivity, are potential as fillers in solar-thermal systems and energy-efficient buildings. [ABSTRACT FROM AUTHOR]

To quantitatively describe the kind of interaction between ion and solvent, it is convenient to use the concept of negative or positive solvation. We have established earlier that diffusion displacement distance ( d ¯ ) of an ion correlates with its solvation type. The ion is solvated positively if the average d ¯ value exceeds the crystallographic (structural) radius of an ion r i ; otherwise, ion solvation is negative. In this paper, we have estimated the length, time and velocity of ion diffusion displacement (hop) for singly charged ions Li + , Na + , K + , Rb + , Cs + , Me 4 N + , Et 4 N + , Bu 4 N + , F - , Cl - , Br - , BPh 4 - over the temperature range from 273.15 K to 473.15 K and for ions Pr 4 N + , I - , NO 3 - , ClO 4 - at 298.15 K in ethylene glycol. The fact of the negative solvation of almost all ions studied (except Li + , Na + , F - ) in ethylene glycol has been established for the first time. It has been shown that Me 4 N + ion has turned out solvated solvophilically in EG as well as in water while ions Et 4 N + , Bu 4 N + , and BPh 4 - appeared to be solvated solvophobically. We have estimated the temperature of transition T tr (from negative to positive ion solvation) for K + and Rb + ions. It physically corresponds to the absence of solvation of the ion ( d ¯ = r i ). [ABSTRACT FROM AUTHOR]

Converting renewable cellulose into glucose via cellulase catalysis for further production of biofuel has been recognized as one of the most promising ways for solving energy crisis. However, the hydrolysis performance of immobilized cellulase was not satisfactory for practical application due to the reduced catalytic efficiency and lack of β-glucosidase (BG) component in cellulase. Here, a facile method was developed to sequentially co-immobilize BG and cellulase by polymeric microparticles with hierarchical structure. In this strategy, BG was firstly entrapped into the cross-linked poly(ethylene glycol) (PEG) microparticles via inverse emulsion polymerization initiated by isopropyl thioxanthone (ITX) under the irradiation of visible light, leaving the formed ITX semi-pinacol (ITXSP) dormant groups on surface of BG-loaded microparticles, which could be further activated by visible light irradiation and initiated a graft polymerization to introduce poly(acrylic acid) (PAA) brush on the PEG core. After that, cellulase was covalently bonded on the PAA chains via carbodiimide reaction. The synergic effect of BG and cellulase was verified in the dual enzyme immobilization system, which led to a better stability at a wide range of temperature and pH than free enzymes. The dual enzymes system exhibited excellent reusability, which could retain 75% and 57% of the initial activity after 10 cycles of hydrolysis of carboxyl methyl cellulose and 5 cycles of hydrolysis of filter paper, respectively, indicative of the potential in biofuel areas in a cost-effective manner. [ABSTRACT FROM AUTHOR]

To provide the progressive global demand for energy, the use of renewable energies is being rapidly developed. Since solar radiation is available in most parts of the earth, the photovoltaic (PV) power plant is one of the worthwhile solutions. As a deficiency, temperature rise in photovoltaic cells leads to a drop in their electrical output power. In this experimental study, the circulation of carbon black nanofluid was investigated as a coolant of PV modules. Both water and ethylene glycol (EG) were used as the base fluids. It is found that all modified cases generate more output power than the conventional one. For instance, water + carbon nanofluid yields 54% more output power compared with the conventional one. To make a real assessment of using nanofluid as a coolant, the electrical consumption by pump and fan must be counted. Therefore, in this study, the net output power is calculated. In the cases of EG and EG + carbon, the net output powers get lower than the conventional module. So, they are not justifiable. In this paper, a modified formula is proposed to calculate the exergy efficiency, in order to achieve more accurate results. Accordingly, from an exergy viewpoint, 16.3% and 4.5% in electrical and thermal exergy efficiencies are achieved, when water + carbon nanofluid was used. Moreover, the values of entropy generation and lost exergy were reported for all considered cases. [ABSTRACT FROM AUTHOR]

In this paper, the semiconductor material BiVO4 was obtained by an adapted process of solution combustion synthesis, using poly(ethylene glycol) (PEG 6000) as an additional stabilizing agent, and deposited on indium-doped tin oxide (ITO) substrate, by the dip-coating deposition process, to build an ITO/BiVO4 thin film heterostructure, which can be used as photoanode in photoelectrochemical (PEC) cell. The ITO/BiVO4 photoanode has its performance evaluated by linear sweep voltammetry (LSV), chronoamperometry, and electrochemical impedance spectroscopy (EIS) techniques, under blue monochromatic light, provided by an InGaN LED source. The LSV curve shows that the photoactivity of the photoanode presents a drastic jump in the current density under illumination and negligible dark current density. Reproducibility of the electrode photoactivity is observed under light-chopped illumination. The decay profile of photocurrent suggests that despite of charge carriers recombination process occurring in the ITO/BiVO4 electrode, it still presents good photoelectrocatalytic efficiency. Additionally, the long-term current stability indicates that the current density stays stable, without considerable decay, for at least one hour. The steady-state photocurrent density obtained is equal 91 µA cm− 2. EIS results showed that under illumination, the charge transfer resistance (Rct) is considerably lower than the dark condition. The PEC performance evaluated for discoloration reaction in rhodamine B (RhB) and methylene blue (MB) shows that the photoelectrochemical system is quite efficient. [ABSTRACT FROM AUTHOR]

This paper focuses on an experimental study of the surface tension of nanofluids based on ethylene glycol with various types of nitride nanoparticles. Samples were prepared using a two-step method with mass content between 1 and 5% of particles. Nanofluids contain three types of nitride nanoparticles: aluminum nitride, silicon nitride and titanium nitride with various particle average sizes. Surface tension of nanofluids was investigated at a constant temperature of 298.15 K with two different techniques: du Noüy ring method and pendant drop method. It is presented that experimental values obtained with both methods are in good agreement with each other. Also, results obtained during this study show that the addition of this type of nanoparticles does not have a significant impact on the surface tension of base fluid for the concentrations and diameters of nitride nanoparticles considered. [ABSTRACT FROM AUTHOR]

Fluorinated compounds with side-chains longer than six carbon have been banned due to their toxicity to environment, organisms and human, so that attentions have been paid on degradable short-chain fluorinated or non-fluorinated materials. Here in this paper, several novel short-chain fluorinated polysiloxanes with multi-functions were synthesized successfully and applied on cotton fabrics. Chemical structure of these fluorinated polysiloxanes were characterized by Fourier-transform infrared spectrum and nuclear magnetic resonance. Liquid repellency, washing durability, thermal stability, fabric style and color deepening of treated cotton fabrics were investigated. Additionally, the effect of benzoyl spacer on the surface wettability was fully studied. Results demonstrate that FPAPS-20@cotton (cotton fabric treated by fluorinated polysiloxane with 20% fluorine content) exhibits the greatest liquid repellency as the contact angles for water, ethylene glycol, glycerol and octane are 150.1°, 132.3°, 138.1° and 105.5°. Moreover, the benzoyl spacer plays a positive role in the durable wettability of FPAPS-20@cotton, resulting in the water contact angles ranging from 150.1° to 146.0° when FPAPS-20@cotton exposes to the water droplet for 20 min. X-ray photoelectron spectroscopy provides the experimental evidence for this result. On the other hand, thermal-gravimetric analysis confirms that the fluoroalkyl segments of the fluorinated polysiloxanes can decelerate the thermal decomposition of cotton fabrics. Moreover, compared with the untreated dyed cotton fabric, the K/S values of cotton fabrics with navy, red and orange color treated with FPAPS-20 increase by 42.61%, 11.00% and 18.18%, respectively. [ABSTRACT FROM AUTHOR]

In this paper, we used neopentyl glycol as a comonomer to participate in the reaction with poly(ethylene terephthalate), and synthesized poly(ethylene terephthalate-co-neopentyl glycol) polyester samples. Through a series of tests, we found that the crystallization ability of the copolymer is closely related to the content of comonomer. Self-nucleation and annealing thermal fractionation were first used to study copolymer, as well as non-isothermal crystallization kinetics analysis were also employed to estimate how neopentyl glycol contents affected the crystallization ability of copolymer. With the increase of neopentyl glycol content, the crystallinity, crystalline rate, Avrami exponent of copolymer changed obviously. Besides, X‑ray diffraction was also used to study the crystalline structures of samples. Results showed that the crystalline of the copolymer have not been changed by the variety of neopentyl glycol content. [ABSTRACT FROM AUTHOR]

Marine coatings protect submerged surfaces from the negative effects of biofouling. In this work, we demonstrate a new method to prepare self-stratified, amphiphilic glycidyl-carbamate (GC)-based (epoxy urethane-based) coatings (AmpSiGC coatings) that have fouling-release properties making them suitable for marine use. The prepared coating systems are unique and durable in character as the bulk coating takes advantage of both epoxy and urethane functionalities while the surface is comprised of both hydrophilic and hydrophobic domains, granting it an amphiphilic characteristic. The experimental approach aimed to evaluate several factors that influence coating performance, including molecular weight of poly (ethylene glycol) (PEG) and PDMS moieties, ratio of hydrophobic (PDMS) and hydrophilic (PEG) components in the system, and the effect of different curing agents. The results demonstrated that polymeric chains of 10,000 M ¯ n PDMS and 750 M ¯ n PEG at 10–15 wt.% each offer substantially improved or comparable fouling-release performance in comparison to commercial marine coatings. This paper reports on the facile synthesis and characterization of the GC resin and GC prepolymers using FTIR and epoxy titrations; surface characterization of the coatings using ATR-FTIR, XPS, and AFM; and fouling-release assessment of the surfaces using laboratory biological assays with the barnacle Amphibalanus amphitrite, the algae Ulva linza and Navicula incerta, and the bacteria Cellulophaga lytica. Several of the AmpSiGC coatings exhibited promising performance, which were better or comparable to the internal and commercial reference coatings. The performance of the systems was dependent on all of the factors considered in this study. [ABSTRACT FROM AUTHOR]

A polemic is given concerning the volumetric properties for acefylline piperazine dissolved in water reported in the published paper by Masood and coworkers. The authors′ measured densities and apparent molar volumes are not consistent with values given in a published follow-up study. [ABSTRACT FROM AUTHOR]

Nanofluid is the colloidal suspension of nanosized solid particles like metals or metal oxides in some conventional fluids like water and ethylene glycol. Due to its unique characteristics of enhanced heat transfer compared to conventional fluid, it has attracted the attention of research community. The forced convection heat transfer of nanofluid is investigated by numerous researchers. This paper critically reviews the papers published on experimental studies of forced convection heat transfer and pressure drop of AlO, TiO and CuO based nanofluids dispersed in water, ethylene glycol and water-ethylene glycol mixture. Most of the researchers have shown a little rise in pressure drop with the use of nanofluids in plain tube. Literature has reported that the pumping power is appreciably high, only at very high particle concentration i.e. more than 5 %. As nanofluids are able to enhance the heat transfer at low particle concentrations so most of the researchers have used less than 3 % volume concentration in their studies. Almost no disagreement is observed on pressure drop results of different researchers. But there is not a common agreement in magnitude and mechanism of heat transfer enhancement. Few studies have shown an anomalous enhancement in heat transfer even at low particle concentration. On the contrary, some researchers have shown little heat transfer enhancement at the same particle concentration. A large variation (2-3 times) in Nusselt number was observed for few studies under similar conditions. [ABSTRACT FROM AUTHOR]

The investigation of the transport properties of binary fluid mixtures remains a topic of interest in relation to the more challenging studies of ternary mixtures. In fact, the study of the phase boundary limits of the Gibbs composition triangle can be the initial step for a more complete analysis of ternary mixtures. In this paper, we apply the dynamic shadowgraphy optical technique to study non-equilibrium fluctuations induced by the presence of a gradient of temperature and/or concentration in the triethylene glycol (TEG)/water system. These thermodiffusion and free-diffusion experiments aim at measuring the transport properties of samples of the studied system at different experimental conditions. We scan both the average temperature and the TEG concentration, which allows us investigating both positive and negative thermodiffusive behaviours. The obtained values of mass diffusion coefficient are consistent with data available in the literature in the range of temperature investigated in this study. The mass diffusion coefficient of the sample prepared at 0.7 w/w TEG concentration are characterised by shadowgraphy following the two proposed methods, exhibiting consistent results. An increase of the mass diffusion coefficient as a function of the average temperature is highlighted. On the other hand, the thermodiffusion coefficient appears to be independent of the average temperature of the sample at 0.3 w/w TEG concentration. [ABSTRACT FROM AUTHOR]

In this paper, the improvement of heat transfer in SWCNTs (Single wall carbon nanotubes) ethylene glycol (EG)-based nanofluid through a complex (irregular) surface is examined. A complex surface is created as a sum of two sine functions in term of fundamental wave and its first harmonic wave. The modeled nonlinear governing equations are made dimensionless PDEs by introducing scaling variables. The resulting nonlinear PDEs are solved numerically using implicit scheme base on backward and central difference approximations. A study of heat transfer is performed in three different ways namely nanofluid flow along flat plate, flow along single sinusoidal surface and complex surface. To check in which case rate of heat transfer increases, the graphs of local Nusselt number, rate of total heat transfer and average Nusselt number are plotted. From these graphs, it is noticed that total heat transfer rate and Nusselt numbers of SWCNTs-based nanofluid increase as compared to base fluid. Also total heat transfer rate for both EG base fluid and nanofluid increases along complex surface as compared to single sinusoidal surface and opposite behavior is observed in Nusselt numbers. It is seen that by adding SWCNTs in EG base fluid, heat transfer rate increases 60% in case of dominant amplitude of fundamental wave and 88% to 98% approximately in case of dominant amplitude of harmonic wave w.r.t. the case of χ = 0.0 , α 1 = 0.5 , α 2 = 0.2. [ABSTRACT FROM AUTHOR]

The paper describes the chemical depolymerization of the polyethylene terephthalate (PET) waste from postconsumer soft drink bottles and a search for the way to use this product. The depolymerized oligoester obtained from glycolysis of PET waste using tiethylene glycol was transesterified with castor oil which resulted in the formation of hydroxyl-functional polyester polyol, with hydroxyl value of 391 mg KOH g−1. In the presented paper, series of castor oil-based waterborne polyurethane (CPU)/silica hybrid dispersions were prepared using dimethylolpropionic acid as an ionic center. The polyurethane prepolymers with pendent castor oil groups were prepared first, and then different concentrations of hydrophilic fumed silicas (0, 0.5, 0.75, 1.0 and 2.0 wt%) were added. For waterborne polyurethane dispersions of hydrophilic fumed silica with the surface area (50 ± 15 m2/g) and a primary particle size of 40 nm in the polymer matrix, ultrasound waves were used. The hybrid dispersions were prepared by adding the required amount of triethylamine and water. The molecular structures and mass of glycolyzed PET oligoesters, castor oil-based polyol and castor oil-based polyurethane-silica hybrid dispersions were estimated by FTIR method and gel permeation chromatography.The incorporation effect of SiO2 nanoparticles into the PU matrix on the thermal and mechanical properties of resulting polyurethane films has been examined by Fourier transform infrared spectroscopy (FTIR), thermogravimetry analysis, differential scanning calorimetry (DSC), SEM microscope, and measurement of the coatings properties. The DSC data results suggest that hard segment glass temperature decreases, but mixed-phase glass transition temperature increases with increasing SiO2 content. The FTIR deconvolution result of the degree of phase separation between oxide nanoparticles and hard segment supports to the DSC analysis. The addition of silica oxide caused the increase in the thermal stability. The T10% and T50% of CPU films (the temperatures where 10 and 50% weight loss occurred) increased with increasing the SiO2 content. UV-Vis spectrophotometry showed that introduction of nanosilica particles into polyurethane enhanced the shielding property of obtained films for UV light. The hardness, adhesion, and gloss quality of the polyurethane films were also determined considering the effect of the phase separation and the SiO2 content, so this paper confirmed the suitability of using these castor oil-based waterborne polyurethane/silica hybrid dispersions as new materials with high-performance coatings materials. [ABSTRACT FROM AUTHOR]

The researchers have diverted their mind to improve the thermophysical properties of convective heat transfer analysis. The studies on nanofluids have been reported because these systems display an anomalous enhancement of convective heat transfer. In this paper, we made a comparative analysis of Maxwell nanofluid with nanoparticles suspended in ethylene glycol through modern approaches of fractional differentiations. The governing equations of Maxwell nanofluid for velocity and temperature are fractionalized in terms of Atangana–Baleanu and Caputo–Fabrizio operators and then solved analytically by invoking Laplace transform to generate series solutions. The general solutions of temperature and velocity field are established in terms of Mittag–Leffler and Fox-H functions, respectively. Modern approaches of fractional differentiations have been analyzed for memory effects on the Maxwell nanofluid for improving the thermophysical properties. The impacts of rheological parameters are underlined for the volume fraction of nanoparticles, relaxation time and single- and multi-walled carbon nanotubes suspended in ethylene glycol. A graphical illustration is depicted to disclose the physical aspects of the problem based on the functionality of modern approaches of fractional differentiations. Our results suggest that thermal conductivity of Maxwell nanofluid increases when nanoparticle's volume fraction increases. [ABSTRACT FROM AUTHOR]