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For a wide range of applications, paper materials require effective protection against the destructive effect of water, which is most effectively realized by superhydrophobic coatings. In recent years, a considerable amount of scientific research has been carried out in this area, focusing particularly on biogenic resources. With this contribution, we go one step further and examine how biogenic materials can be transferred into aqueous dispersions and coated onto paper via existing technologies. With this paper coating, based on a hydrophobic cellulose derivative in combination with a structurally similar wax, thermally regenerable flower-like surface morphologies are obtained via self-assembly, where the hydrophobic cellulose polymer acts as a structural template for the co-crystallization of the wax component. Such hydrophobic structures in the low micrometer range ensure perfectly water-repellent paper surfaces with contact angles > 150° starting from coating weights of 5 g/m2. The dispersion can be successfully applied to a variety of commercially available paper substrates, whereby the effects of different roughness, porosity, and hydrophobicity were investigated. In this context, a certain roughness of the base paper (Sa ~ 1.5–3 µm) was found to be beneficial for achieving the highest possible contact angles. Furthermore, the approach proved to be paper process-compatible, recyclable, and regenerable, whereby the processing temperatures allow the coating properties to be thermally generated in situ. With this work, we demonstrate how biogenic waxes are very well suited for superhydrophobic, regenerative coatings and, importantly, how they can be applied from aqueous coatings, enabling simple transfer into the paper industry. [ABSTRACT FROM AUTHOR]

We report on the development of an electrochemical probe for the trace analysis of 2,4,6-trinitrotoluene (TNT) in soil samples. The probe is a combination of graphite electrodes, filter paper, with ethylene glycol and choline chloride as the solvent/electrolyte. Square wave chromatovoltammograms show the probes have a sensitivity for TNT of 0.75 nA/ng and a limit of detection of 100 ng. In addition, by taking advantage of the inherent paper chromatography step, TNT can be separated in both time and cathodic peak potential from 4-amino-dinitrotolene co-spotted on the probe or in soil samples with the presence of methyl parathion as a possible interferent. [ABSTRACT FROM AUTHOR]

In this paper, we report the fabrication of highly conductive poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT:PSS)/cellulose nanofiber (CNF) nanocomposite paper with excellent flexibility through post-treatment with an organic solvent. The post-treated PEDOT:PSS/CNF porous nanocomposite papers showed a lower sulfur content, indicating the removal of residual PSS. The electrical conductivity of PEDOT:PSS/CNF porous nanocomposite paper was increased from 1.05 S/cm to 123.37 S/cm and 106.6 S/cm by post-treatment with dimethyl sulfoxide (DMSO) and ethylene glycol (EG), respectively. These values are outstanding in the development of electrically conductive CNF composites. Additionally, the highly conductive nanocomposite papers showed excellent bending stability during bending tests. Cyclic voltammetry (CV) showed a Faradaic redox reaction and non-Faradaic capacitance due to the redox activity of PEDOT:PSS and large surface area, respectively. Electrochemical energy storage ability was evaluated and results showed that capacitance improved after post-treatment. We believe that the highly conductive PEDOT:PSS/CNF porous nanocomposite papers with excellent flexibility described here are potential candidates for application in porous paper electrodes, flexible energy storage devices, and bioengineering sensors. [ABSTRACT FROM AUTHOR]

This paper presents the continuation of experimental investigations conducted by the present authors to measure and compare the thermal and fluid dynamic performance of a residential hydronic air coil using nanofluids. The prior experiments were limited to testing only one volumetric concentration (1%) of aluminum oxide (Al2O3) nanofluid. They compared it with the base fluid, a 60% ethylene glycol/40% water mixture by mass (60% EG). The original tests revealed some deficiencies in the experimental setup, which was subsequently revised and improved. This paper summarizes the results of experiments from the improved test bed using three concentrations of Al2O3 nanofluids: 1, 2, and 3% volumetric concentrations prepared with an average particle size of 45 nm in a 60% EG dispersion. The test bed in these experiments simulates a small air handling system typical of heating, ventilation, and air conditioning (HVAC) applications in cold regions. Entering conditions for the air and liquid were selected to emulate typical commercial air handling systems operating in cold climates. Contrary to previous findings, our test results revealed that nanofluids did not perform as well as expected. Prior predictions from many analytical and numerical studies had promised significant performance gain. The performance of the 1% nanofluid was generally equal to that of the base fluid under identical inlet conditions. However, the performance of the 2% and 3% nanofluids was considerably lower than that of the base fluid. The higher concentration nanofluids exhibited heat rates up to 14.6% lower than the 60% EG and up to 44.3% lower heat transfer coefficient. The 1% Al2O3/60% EG exhibited a 100% higher pressure drop across the coil than the base fluid, considering equal heat output. This performance degradation was attributed to the inability to maintain nanofluid dispersion stability, agglomeration, and subsequent decline in the thermophysical properties. [ABSTRACT FROM AUTHOR]

In this paper, a heat generator with fluid agitation is developed and experimentally studied. This heat generator can convert kinetic energy from a wind turbine directly to thermal energy through the process of viscous dissipation—a process achieved through the agitation of the working fluid inside a container. In the experimental study, an electric motor (instead of a wind turbine) was used to provide the kinetic energy input to the heat generator. The torque, rotational speed, and temperature rise in the fluid were measured. Using the measured quantities, the efficiency of kinetic energy to sensible heat conversion was calculated. Experiments were conducted to investigate the effects of different impellers, rotational speeds, and working fluids, including distilled water, ethylene glycol (EG), and their respective nanofluids, with A l 2 O 3 nanoparticles at different concentrations. The study also found that the temperature rise in fluids due to viscous dissipation was influenced by the specific heat of the fluid, suggesting that the heat generator can be optimized for energy storage with high-specific-heat fluids, such as water, or for achieving a higher temperature rise with low-specific-heat fluids, such as ethylene glycol. The experimental results indicated that the heat generator was up to 90% efficient in converting kinetic energy to thermal energy. The study revealed that, for constant power input, the heat dissipation rate depends solely on the vessel's geometry, not the fluid properties. Optimizing the impeller design and baffles within the vessel is crucial for maximizing power input. For applications, a wind turbine can power this heat generator to provide heat to a house or a commercial building. [ABSTRACT FROM AUTHOR]

High-molecular-weight poly(L-lactide)-b-poly(ethylene glycol)-b-poly(L-lactide) (PLLA-PEG-PLLA) is a flexible and biodegradable bioplastic that has promising potential in flexible food packaging but it has no antibacterial ability. Thus, in this work, the effect of zinc oxide nanoparticles (nano-ZnOs) which have antimicrobial activity on various properties of PLLA-PEG-PLLA was determined. The addition of nano-ZnOs enhanced the crystallization, tensile, UV-barrier, and antibacterial properties of PLLA-PEG-PLLA. However, the crystallization and tensile properties of nanocomposite films decreased again as the nano-ZnO increased beyond 2 wt%. The nano-ZnO was well distributed in the PLLA-PEG-PLLA matrix when the nano-ZnO content did not exceed 2 wt% and exhibited some nano-ZnO agglomerates when the nano-ZnO content was higher than 2 wt%. The thermal stability and moisture uptake of the PLLA-PEG-PLLA matrix decreased and the film's opacity increased as the nano-ZnO content increased. The PLLA-PEG-PLLA/ZnO nanocomposite films showed good antibacterial activity against bacteria such as Escherichia coli and Staphylococcus aureus. It can be concluded that nano-ZnOs can be used as a multi-functional filler of the flexible PLLA-PEG-PLLA. As a result, the addition of nano-ZnOs as a nucleating, reinforcing, UV-screening, and antibacterial agent in the flexible PLLA-PEG-PLLA matrix may provide protection for both the food and the packaging during transportation and storage. [ABSTRACT FROM AUTHOR]

Simple Summary: In order to improve the comprehensive utilization of oil tea seed meal and increase the comprehensive economic benefits of the oil tea industry. In this paper, the low eutectic solvent was used as the extraction system, and the ultrasonic extraction method was combined with the enzymatic method to jointly extract the tea saponins. It was further purified with a large-pore adsorption resin to develop a set of environmentally friendly, energy-saving, and efficient tea saponin extraction and purification processes. On this basis, the tea saponins extracted from oil tea seed meal were further analyzed for antioxidant capacity and bacteriostatic activity. The results provided the scientific experimental basis and theoretical support for the efficient use of oil tea by-products. Tea saponins have high surface-active and biological activities and are widely used in chemicals, food, pharmaceuticals, and pesticides. Tea saponins are usually extracted using ethanol or water, but both methods have their disadvantages, including a negative impact on the environment, high energy consumption, and low purity. In this study, we explored an effective process for extracting tea saponins from tea meal using deep eutectic solvents combined with ultrasonic extraction and enzymatic techniques. The experimental results showed that a high extraction efficiency of 20.93 ± 0.48% could be achieved in 20 min using an ultrasonic power of 40% and a binary DES consisting of betaine and ethylene glycol (with a molar ratio of 1:3) at a material–liquid ratio of 1:35 and that the purity of the tea saponins after purification by a large-pore adsorption resin reached 95.94%, which was higher than that of commercially available standard tea saponin samples. In addition, the extracted tea saponins were evaluated for their antioxidant and bacteriostatic activities using chemical and biological methods; the results showed that the tea saponins extracted using these methods possessed antioxidant properties and displayed significant antibacterial activity. Therefore, the present study developed a method for using deep eutectic solvents as an environmentally friendly technological solution for obtaining high-purity tea saponins from tea meal oil. This is expected to replace the current organic solvent and water extraction process and has great potential for industrial development and a number of possible applications. [ABSTRACT FROM AUTHOR]

Although the incidence of infections in orthopedic surgeries, including periprosthetic surgeries, remains low at approximately 1–2%, the number of surgeries and the incidence of drug-resistant bacteria is increasing. The cost and morbidity associated with revision surgeries are huge. More effective drug combinations and delivery methods are urgently needed. In this paper, three anti-infective drugs (vancomycin, rifampicin, and silver sulfadiazine) have been jointly and effectively electrospun in thin (0.1 mm) flexible nanofiber mats of either poly (methyl methacrylate) (PMMA) or poly (lactic-co-glycolic acid) (PLGA). The inclusion of poly (ethylene glycol) (PEG) enabled optimal drug release with a reduced water contact angle for wetting. The controlled release of these three agents from 20% PEG (w/w to polymer)-blended PMMA or PLGA nanofiber mats may allow for the prophylactical prevention of implant-related infections or provide methods to treat orthopedic infections at the time of revision surgeries. These combinations of drugs provide excellent additive or synergistic antibiotic action against a broader spectrum of bacteria than each drug alone. [ABSTRACT FROM AUTHOR]

Natural gas hydrate (NGH) is a potential future energy resource. More than 90% of NGH resources exist in the pore medium of seafloor sediments. During the development of deep-sea oil and gas fields, wellbore pipelines are often clogged due to the synthesis of gas hydrates, and the addition of thermodynamic inhibitors is a common solution to prevent hydrate synthesis. In this paper, the effects of two single inhibitors, sodium chloride and ethylene glycol, as well as hybrid inhibitors combining these two inhibitors on the synthesis of methane hydrates were investigated using the self-developed one-dimensional gas hydrate exploitation simulation test apparatus. The effects of single and hybrid inhibitors were investigated in terms of the hydrate synthesis volume and gas–water two-phase conversion rate. The results show that the hybrid inhibitor has a better inhibitory effect on hydrate synthesis with the same initial synthesis driving force. When the concentration of inhibitors is low, salt inhibitors can have a better inhibitory effect than alcohol inhibitors. However, in the mixed inhibitor experiment, increasing the proportion of ethylene glycol in the mixed inhibitor can more effectively inhibit the synthesis of hydrates than increasing the proportion of sodium chloride in the mixed inhibitor. [ABSTRACT FROM AUTHOR]

The paper deals with an experimental investigation of a new approach for cooling the external heat exchange surfaces of a cooler using an air pressure nozzle system. The G12+ coolant (50:50 ethylene glycol/water concentrate) is heated to an operating temperature of 80 °C and cooled by a cooler. Three ways of forced cooling of the external heat exchange surfaces of the cooler are experimentally compared—fan, nozzles, and a combination of nozzles and fan. The spacing between the nozzles and the cooler is variable from 60 to 170 mm in inline and staggered nozzle arrangements. Coolant temperatures in the cooler inlet and outlet pipes are recorded by thermistors. The air pressure nozzle system achieved an improvement in the cooling process compared to a conventional fan. At a spacing of 160 mm, the heat exchange surface is completely covered by the air flow, which leads to a reduction in cooling time and an increase in the temperature difference. The maximum temperature difference of 28.84 °C and 16.90 °C for staggered arrangement of nozzles at a spacing of 160 mm are achieved for the combination of nozzles with fan and nozzles, respectively. When comparing 60 mm and 160 mm spacing, there was an increase in thermal performance of 70.3%, 55.99%, 6.20%, and 1.83% for inline nozzles, staggered nozzles, fan with inline nozzles, and fan with staggered nozzles, respectively. The air nozzle system fully replaces the fan in the cooling process and achieves improved heat dissipation, making the cooling process significantly shorter and more efficient. In addition, the air nozzle system can also be used as an additional equipment for intensification of heat dissipation in combination with the fan. [ABSTRACT FROM AUTHOR]

This paper focuses on the environmental leaching of antimony, a critical mineral, using deep eutectic solvents. Mining residues often contain embedded antimony, posing environmental risks. Deep eutectic solvents, known for being low in toxicity, cost-effective, and environmentally friendly, present a promising avenue for sustainable antimony extraction. The study focuses on optimizing the leaching process through experimental analysis by considering variables such as temperature, time, and percentage of solids. Different deep eutectic solvent (DES) compositions are being studied, including choline chloride with malonic acid, thiourea, and ethylene glycol in different molar ratios, to identify the most effective solvent system for antimony extraction. A sample, originally obtained from mining waste produced via the flotation of antimonite ore, was used to test these three types of DESs. By optimizing the leaching process by changing the ratio of solid and liquid components, as well as the amount of oxidizing agent up to 3 g, iodine, yields of up to 100% were achieved after leaching for 4 h at 100 °C. The aim of the study is to advance sustainable resource management by providing knowledge on an ecological and feasible method of extracting antimony from mine waste, leading to more conscious and efficient resource practices in the mining sector. [ABSTRACT FROM AUTHOR]

The release of drugs from core/shell nanoparticles (NPs) is a crucial factor in ensuring high reproducibility, stability, and quality control. It serves as the scientific basis for the development of nanocarriers. Several factors, such as composition, composition ratio, ingredient interactions, and preparation methods, influence the drug release from these carrier systems. The objective of our study was to investigate and discuss the relationship between modifications of core/shell NPs as multifunctional drug delivery systems and the properties and kinetics of drug release using an in vitro drug release model. In this paper, we prepared four core/shell NPs consisting of a superparamagnetic iron oxide NPs (Fe3−δO4) core encapsulated by a biocompatible thermo-responsive copolymer, poly(2-(2-methoxy) ethyl methacrylate-oligo (ethylene glycol) methacrylate) or P(MEO2MAx-OEGMA100−x) (where x and 100 − x represented the molar fractions of MEO2MA and OEGMA, respectively), and loaded with doxorubicin (DOX). Colloidal behavior measurements in water and PBS as a function of temperature showed an optimization of the lower critical solution temperature (LCST) depending on the molar fractions of MEO2MA and OEGMA used to form each NPs. In vitro studies of doxorubicin release as a function of temperature demonstrated a high control of release based on the LCST. A temperature of approximately 45 °C for 60 h was sufficient to release 100% of the DOX loaded in the NPs for each sample. In conclusion, external stimuli can be used to modulate the drug release behavior. Core/shell NPs hold great promise as a technique for multifunctional drug delivery systems. [ABSTRACT FROM AUTHOR]

The thermophysical properties of various types of nanofluids are often studied to find more effective working fluids for heat transfer applications. In this paper, the mass density, isobaric heat capacity, thermal conductivity, dynamic viscosity surface tension, and electrical properties of calcium carbonate-ethylene glycol (CaCO 3 -EG) nanofluids were investigated. The samples with mass fractions of 0.01, 0.02, and 0.03 were prepared with a two-step method and studied as well as pure base fluid (ethylene glycol). The measurements were conducted at temperatures between 283.15 and 313.15 K and the obtained results show the impact of CaCO 3  nanoparticles on the thermophysical and electrical properties of ethylene glycol. [ABSTRACT FROM AUTHOR]

The colorless and odorless ethylene glycol is prone to unknowingly causing poisoning, making preventive monitoring of ethylene glycol necessary. In this paper, scandium (III) trifluoromethanesulfonate was used as a catalyst to successfully prepare covalent organic framework (COF) nanospheres linked by imines at room temperature. The COF nanospheres were characterized by XRD, SEM, TEM, FT-IR, UV-Vis and BET. The results show that COF nanospheres have rough surfaces and a large number of mesoporous structures, which greatly increase the active sites on the surface of the sensing material and enhance the gas sensing performance. The sensing results showed that the prepared imine-conjugated COF nanospheres exhibited a good response–recovery ability for 10 consecutive response–recovery cycles for ethylene glycol at room temperature and had a theoretical detection limit of 40 ppb. In addition, the responses of COF nanospheres to nearly 20 interfering gases, including HCl, HNO3, phenol, formaldehyde and aniline, are relatively low compared to the response to ethylene glycol, indicating that the COF nanospheres have high selectivity towards ethylene glycol. The COF nanospheres show good sensitivity and selectivity for the detection of ethylene glycol, which should be attributed to the large specific surface area, hydrogen bonding interactions, and high defects. This work provides an effective method for the detection of ethylene glycol and expands the application field of COF materials. [ABSTRACT FROM AUTHOR]

Gum rosin is an important agricultural commodity which is widely used as a raw material for various industries. However, gum rosin has low stability, crystallizes easily, and tends to oxidize. This is due to carboxyl groups and conjugated double bonds in gum rosin's structure. Therefore, to reduce these weaknesses, it is necessary to modify the rosin compound to achieve better stability via the esterification process. This paper surveys esterification agents such as glycerol, pentaerythritol, methanol, ethylene glycol, polyethylene glycol (PEG), allyl group, and starch Rosin ester. The product is used in the manufacture of pressure-sensitive adhesives, drug delivery, solder flux for electronic devices, as a plasticizer, and as a coating agent in fertilizers. In general, the esterification reaction between alcohols and carboxylic acids is very slow without a catalyst. Heterogeneous catalysts have the advantage of controlling size, structure, spatial distribution, surface composition, thermal-chemical stability, and selectivity. Among the catalysts for gum rosin esterification are ZSM-5, Fe3O4, ZnO, Calcium, TiO2, Kaolin, and Al2O3, among others. Different catalysts and esterification agents can produce various physical and chemical properties of rosin ester and will result in specific rosin ester products, such as glycerol ester, pentaerythritol ester, methyl ester, glycol ester, allyl ester, and acid starch-based rosin. [ABSTRACT FROM AUTHOR]

Solar concentrator collectors have the potential of meeting the medium- and high-temperature thermal energy demands of the world. A heat transfer fluid (HTF) is a vital component of a concentrating system to transfer and store thermal energy. This paper presents the design development of a solar paraboloidal dish concentrator (SPDC) and a study of selected HTFs using the storage receiver system of the concentrator. The locally designed SPDC (diameter 1.21 m and height 0.20 m) has features like light weight, effortless tracking, convenient transportation along with high optical and thermal performance. Three HTFs, silicone oil (SO), engine oil (EO) and ethylene glycol (EG), are selected based on their favorable properties for medium temperature (150–300 °C) applications. The characteristic parameters of HTFs, heating rate (Rh), instant thermal efficiency (ηith) and the overall heat loss coefficient (UL), are illustrated and determined experimentally. A new characteristic parameter, the normalized maximum fluid temperature (Tnf), is also introduced in the paper. In the heating test, the maximum attained temperatures by fluids, SO, EO and EG are found to be 240 °C, 180 °C and 160 °C, respectively. The thermal efficiencies of SO, EO and EG are determined to be 45, 36 and 31%, respectively. The heating rate of 6.56 °C/s is found to be the maximum for SO. Through the cooling test, the overall heat loss coefficient (UL) is computed to be 14 W/mK, which is the least among the three fluids compared. The high thermal performance, environmental safety and chemical stability of silicone oil make it suitable for use in concentrators for medium-temperature heat transfer and storage applications. [ABSTRACT FROM AUTHOR]

In this paper, we present an alternative technique for the removal of Brilliant Green dye (BG) in aqueous solutions based on the application of molecularly imprinted polymer (MIP) as a selective adsorbent for BG. The MIP was prepared by bulk radical polymerization using BG as the template; methacrylic acid (MAA) as the functional monomer, selected via computer simulations; ethylene glycol dimethacrylate (EGDMA) as cross-linker; and 2,2′-azobis(2-methylpropionitrile) (AIBN) as the radical initiator. Scanning electron microscopy (SEM) analyses of the MIP and non-molecularly imprinted polymer (NIP)—used as the control material—showed that the two polymers exhibited similar morphology in terms of shape and size; however, N2 sorption studies showed that the MIP displayed a much higher BET surface (three times bigger) compared to the NIP, which is clearly indicative of the adequate formation of porosity in the former. The data obtained from FTIR analysis indicated the successful formation of imprinted polymer based on the experimental procedure applied. Kinetic adsorption studies revealed that the data fitted quite well with a pseudo-second order kinetic model. The BG adsorption isotherm was effectively described by the Langmuir isotherm model. The proposed MIP exhibited high selectivity toward BG in the presence of other interfering dyes due to the presence of specific recognition sites (IF = 2.53) on its high specific surface area (112 m2/g). The imprinted polymer also displayed a great potential when applied for the selective removal of BG in real river water samples, with recovery ranging from 99 to 101%. [ABSTRACT FROM AUTHOR]

The paper deals with the actual topic of mechanical properties of 3D prints made from the polymer material rPET-G and its changes. Using this material in additive technology has great potential in the automotive industry. The research evaluates five different post-processing modifications of 3D prints from rPET-G (recycled polyethylene terephthalate-glycol) material produced by the Fused Filament Fabrication technology. The post-processing included the chemical smoothing of the samples using dichloromethane vapors and heat treatment in an annealing furnace. An epoxy resin, a synthetic coating, and a water-based coating were also applied. The standard was represented by samples without post-processing modifications, both in the form of recycled material and in the form of virgin PET-G. The texture of the samples was evaluated according to EN ISO 4287. Furthermore, the moisture absorption of the samples was evaluated using the gravimetric method according to EN ISO 62. The mechanical testing of the samples was carried out using a tensile test (EN ISO 527-2), a three-point bending test (EN ISO 178), impact strength (EN ISO 179-2), and a cupping test (EN ISO 1520). Degradation of the coatings took place using cyclic tests, which used a combination of exposure in a salt fog environment and in a climate chamber. The results of the experiments indicate that heat treatment appears to be a universal post-processing technology, as this method statistically improves not only the mechanical properties but also significantly reduces moisture absorption. [ABSTRACT FROM AUTHOR]

This paper demonstrates the in situ sinter bonding of Ag microparticle pastes to a Si substrate via the temporal formation and decomposition of Ag carboxylate on the surface of Ag microparticles. This was proposed via the investigation of Ag sinter bonding using the redox reaction between Ag2O and ethylene glycol, which achieved a bonding strength above 30 MPa even for the bonding temperature at 220 °C. Thermal analysis was used to identify the product of the redox reaction between Ag2O and ethylene glycol and determine the bonding temperature because the final reaction facilitates the interfacial sinter bonding with the substrate. Fourier-transform infrared spectroscopy and nuclear magnetic resonance results indicated the in situ formation of Ag salts of carboxylic acids, such as Ag oxalate on the surface of Ag microparticles. Therefore, the sinter bonding process enabled by the in situ formation and subsequent decomposition of these Ag salts was investigated using Ag microparticles and oxalic acid. Observations of the surface and interfacial morphology of the Ag particles after heating revealed the formation of Ag nanoparticles on the surfaces of the microparticles and the formation of sintering necks between the particles. The bonding experiments demonstrated a significant increase in strength with the addition of oxalic acid to the Ag paste due to the enhanced interfacial sinter bonding with the substrate. The in situ formation and decomposition of Ag salts are promising strategies for improving sintered bonds in electronic devices because they can provide enhanced localized sinter bonding using stable insert materials. [ABSTRACT FROM AUTHOR]

This paper describes a novel nanoformulation for dual MRI/US in vivo monitoring of drug delivery/release. The nanosystem was made of a perfluoropentane core coated with phospholipids stabilized by glycol chitosan crosslinked with triphosphate ions, and it was co-loaded with the prodrug prednisolone phosphate (PLP) and the structurally similar MRI agent Gd-DTPAMA-CHOL. Importantly, the in vitro release of PLP and Gd-DTPAMA-CHOL from the nanocarrier showed similar profiles, validating the potential impact of the MRI agent as an imaging reporter for the drug release. On the other hand, the nanobubbles were also detectable by US imaging both in vitro and in vivo. Therefore, the temporal evolution of both MRI and US contrast after the administration of the proposed nanosystem could report on the delivery and the release kinetics of the transported drug in a given lesion. [ABSTRACT FROM AUTHOR]

This study investigated the influence of microstructure on the performance of Ag inkjet-printed, resistive temperature detectors (RTDs) fabricated using particle-free inks based on a silver nitrate (AgNO3) precursor and ethylene glycol as the ink solvent. Specifically, the temperature coefficient of resistance (TCR) and sensitivity for sensors printed using inks that use monoethylene glycol (mono-EG), diethylene glycol (di-EG), and triethylene glycol (tri-EG) and subjected to a low-pressure argon (Ar) plasma after printing were investigated. Scanning electron microscopy (SEM) confirmed previous findings that microstructure is strongly influenced by the ink solvent, with mono-EG inks producing dense structures, while di- and tri-EG inks produce porous structures, with tri-EG inks yielding the most porous structures. RTD testing revealed that sensors printed using mono-EG ink exhibited the highest TCR (1.7 × 10−3/°C), followed by di-EG ink (8.2 × 10−4/°C) and tri-EG ink (7.2 × 10−4/°C). These findings indicate that porosity exhibits a strong negative influence on TCR. Sensitivity was not strongly influenced by microstructure but rather by the resistance of RTD. The highest sensitivity (0.84 Ω/°C) was observed for an RTD printed using mono-EG ink but not under plasma exposure conditions that yield the highest TCR. [ABSTRACT FROM AUTHOR]

New microfluidic lab-on-a-chip capabilities are enabled by broadening the toolkit of devices that can be created using microfabrication processes. For example, complex geometries made possible by 3D printing can be used to approach microfluidic design and application in new or enhanced ways. In this paper, we demonstrate three distinct designs for microfluidic one-way (check) valves that can be fabricated using digital light processing stereolithography (DLP-SLA) with a poly(ethylene glycol) diacrylate (PEGDA) resin, each with an internal volume of 5–10 nL. By mapping flow rate to pressure in both the forward and reverse directions, we compare the different designs and their operating characteristics. We also demonstrate pumps for each one-way valve design comprised of two one-way valves with a membrane valve displacement chamber between them. An advantage of such pumps is that they require a single pneumatic input instead of three as for conventional 3D-printed pumps. We also characterize the achievable flow rate as a function of the pneumatic control signal period. We show that such pumps can be used to create a single-stage diffusion mixer with significantly reduced pneumatic drive complexity. [ABSTRACT FROM AUTHOR]

Ethylene glycol (EG) produced from biomass is a promising candidate for several new applications. In this paper, EG derivatives such as mono- and di-tert-butyl ethers are considered. However, accurate thermodynamic data are essential to optimise the technology of the direct tert-butyl ether EG synthesis reaction or reverse process isobutene release. The aim of this work is to measure the vapour pressures and combustion energies for these ethers and determine the vaporisation enthalpies and enthalpies of formation from these measurements. Methods based on the First and Second Law of Thermodynamics were combined to discover the reliable thermodynamics of ether synthesis reactions. The thermochemical data for ethylene glycol tert-butyl ethers were validated using structure–property correlations and quantum chemical calculations. The literature results of the equilibrium study of alkylation of EG with isobutene were evaluated and the thermodynamic functions of ethylene glycol tert-butyl ethers were derived. The energetics of alkylation determined according to the "First Law" and the "Second Law" methods agree very well. Some interesting aspects related to the entropy of ethylene glycol tert-butyl ethers were also revealed and discussed. [ABSTRACT FROM AUTHOR]

This work proposes an efficient catalytic recovery and utilization method for waste polyurethane foam. This method uses ethylene glycol (EG) and propylene glycol (PPG) as two-component alcohololytic agents for the alcoholysis of waste polyurethane foams. For the preparation of recycled polyethers, the conditions of different catalytic degradation systems were catalyzed by duplex metal catalysts (DMC) and alkali metal catalysts, and a synergy with both was also used. The experimental method was adopted with the blank control group and was set up for comparative analysis. The effect of the catalysts on the recycling of waste polyurethane foam was investigated. The catalytic degradation of DMC and the alkali metal catalysts alone, as well as the synergistic effect of the two catalysts, was explored. The findings revealed that the NaOH and DMC synergistic catalytic system was the best, and that the system activity was high under a two-component catalyst synergistic degradation. When the amount of NaOH added in the degradation system was 0.25%, the amount of DMC added was 0.04%, the reaction time was 2.5 h, and the reaction temperature was 160 °C, the waste polyurethane foam was completely alcoholized, and the prepared regenerated polyurethane foam had high compressive strength and good thermal stability. The efficient catalytic recycling method of waste polyurethane foam proposed in this paper has certain guiding and reference values for the practical production of solid-waste-recycled polyurethane. [ABSTRACT FROM AUTHOR]

Pollution with organic dyes is one of the most typical environmental problems related to industrial wastewater. The removal of these dyes opens up new prospects for environmental remediation, but the design of sustainable and inexpensive systems for water purification is a fundamental challenge. This paper reports the synthesis of novel fortified hydrogels that can bind and remove organic dyes from aqueous solutions. These hydrophilic conetworks consist of chemically modified poly(ethylene glycol) (PEG-m) and multifunctional cellulose macromonomers ("cellu-mers"). Williamson etherification with 4-vinylbenzyl chloride (4-VBC) is used to modify PEGs of different molecular masses (1, 5, 6, and 10 kDa) and cellobiose, Sigmacell, or Technocell™ T-90 cellulose (products derived from natural renewable resources) with polymerizable/crosslinkable moieties. The networks are formed with good (75%) to excellent (96%) yields. They show good swelling and have good mechanical properties according to rheological tests. Scanning electron microscopy (SEM) reveals that cellulose fibers are visibly embedded into the inner hydrogel structure. The ability to bind and remove organic dyes, such as bromophenol blue (BPB), methylene blue (MB), and crystal violet (CV), from aqueous solutions hints at the potential of the new cellulosic hydrogels for environmental cleanup and clean water safeguarding. [ABSTRACT FROM AUTHOR]

This paper reports an experimental investigation of the heat transfer features of new and recycled Alumina (Al2O3) nanofluids (NFs) in the pool boiling (PB) system. The mixture of ethylene glycol (EG) and distilled water (DW) is selected as the base fluid (BF), and NFs samples of two low concentrations (0.01 and 0.05 vol.%) of Al2O3 nanoparticles were prepared. Furthermore, the characteristics of the prepared NFs are evaluated to investigate the heat transfer performance as well as the reusability of the NFs for long-term applications and recycling consideration. Although there have been a large number of boiling studies with NFs, the current study is the first of its kind that addresses the mentioned operation conditions of recycling NF samples. The results are compared with the relevant BF in terms of properties, critical heat flux (CHF), burnout heat flux (BHF), and the convection coefficient of the Al2O3 NFs in the PB system. The results showed good enhancements in both CHF and BHF of these NFs yielding up to 60% and 54% for BHF at 0.05 vol.%, respectively. The reusage of the previously used (recycled) Al2O3 NF showed a considerable increase in heat transfer performance compared to base fluids but slightly lower than the newly prepared one. The results of the reused nanofluids demonstrate the great prospects of their recyclability in heat transfer systems and processes such as in pool boiling. [ABSTRACT FROM AUTHOR]

Curcumin comes from the plant species Curcuma longa and shows numerous pharmacological activities. There are numerous curcumin formulations with gels or cyclodextrins in order to increase its solubility and bioavailability. This paper presents the formulation of complex of curcumin with 2-hydroxypropyl-β-cyclodextrin in a thermosensitive hydrogel, based on N-isopropylmethacrylamide and N-isopropylacrylamide with ethylene glycol dimethacrylate as a crosslinker. The product was characterized by chemical methods and also by FTIR, HPLC, DSC, SEM, XRD. The results show that synthesis was successfully done. With an increase in the quantity of crosslinker in the hydrogels, the starting release and the release rate of curcumin from the formulation of the complex with hydrogels decreases. The release rate of curcumin from the gel complex formulation is constant over time. It is possible to design a formulation that will release curcumin for more than 60 days. In order to determine the mechanism and kinetics of curcumin release, various mathematical models were applied by using the DDSolver package for Microsoft Excel application. The Korsmeyer-Peppas model best describes the release of curcumin from the gel formulation of the complex, while the values for the diffusion exponent (0.063–0.074) shows that mechanism of the release rate is based on diffusion. [ABSTRACT FROM AUTHOR]

The "unprotected" metal and alloy nanoclusters (UMCs) prepared by the alkaline ethylene glycol method, which are stabilized with simple ions and solvent molecules, have the advantages of a small particle size, a narrow size distribution, good stability, highly efficient preparation, easy separation, surface modification and transfer between different phases. They can be composited with diverse materials to prepare catalytic systems with controllable structures, providing an effective means of studying the different factors' effects on the catalytic properties separately. UMCs have been widely used in the development of high-performance catalysts for a variety of functional systems. This paper will review the research progress on the formation mechanism of the unprotected metal nanoclusters, exploring the structure–function relationship of metal nanocluster catalysts and the preparation of excellent metal catalysts using the unprotected metal nanoclusters as building blocks or starting materials. A principle of the influence of carriers, ligands and modifiers in metal nanocluster catalysts on the catalytic properties is proposed. [ABSTRACT FROM AUTHOR]

The paper presents the preparation of new ionic liquids based on hexamethylenetetramine with bis(trifluoromethanesulfonyl)imide and dicyanamide anion, which were characterized in detail in terms of their purity (Ion Chromatography) and thermal properties (Differential Scanning Calorimetry), as well as stability. The obtained substances were used to develop curing systems with ethylene glycol, which were successfully tested for their application with bisphenol A diglycidyl ether molecule. In addition, the curing process and its relationship to the structure of the ionic liquid are characterized in detail. The research showed that hexamethylenetetramine-based new ionic liquids can be successfully designed using well-known and simple synthetic methods—the Delepine reaction. Moreover, attention was paid to their stability, related limitations, and the application of hexamethylenetetramine-based ionic liquids in epoxy-curing systems. [ABSTRACT FROM AUTHOR]

In order to simplify the experimental procedure and treatment procedure, we preserved the embryonic callus (EC) of Fraxinus mandshurica more efficiently. In this paper, we established a method for cryopreservation of EC of F. mandshurica by vitrification. EC was subcultured for 7–10 days (d). Vigorous EC with good growth conditions were selected, and cryopreservation was performed by vitrification. The best pre-culture method was to pre-culture EC on 0.5 mol·L−1 sucrose medium for 3 d, load and culture in the liquid woody plant medium (WPM) supplemented with 2 mol·L−1 glycerol and 0.4 mol·L−1 sucrose for 60 min, then dehydrate in 2 mL of plant vitrification solution 2 (PVS2) (30% glycerol + 15% dimethyl sulfoxide (DMSO) + 15% ethylene glycol + 0.4 mol·L−1 sucrose + liquid WPM). EC was rewarmed in a 40 °C water bath for 2 min after cooling in liquid nitrogen. The procedure for cryopreservation of F. mandshurica EC by the vitrification method established in this experiment is relatively reliable. The results from the present study provide a technical reference for improving the cryopreservation of F. mandshurica EC. [ABSTRACT FROM AUTHOR]

The current paper proposes a novel multi-generation system, integrated with compound parabolic collectors and a biomass combustor. In addition to analyzing the comprehensive system in a steady state, the feasibility of using nanofluids as heat transfer fluids in the solar cycle and their effect on the overall performance of the system was studied. The multi-generation system is generally designed for generating electricity, cooling, freshwater, drying, hot water, and hydrogen, with the help of six subsystems. These include a double stage refrigeration system, an organic Rankine cycle, a steam Rankine cycle, a dryer, a proton exchange membrane electrolyzer, and a multistage flash distillation system. Two types of nanoparticles (graphene, silver), which have various high-quality properties when used within ethylene glycol, were chosen as absorbing fluids in the solar cycle. The performance parameters of the base case thermodynamic analysis and some of the variable parameters were calculated, and their effect on system performance was determined. According to the results, a spike in solar irradiation, ambient temperature, output temperature of biomass combustor and nanofluids' concentration positively affected the overall system performance. The results also clearly showed an improvement in system performance when using nanofluids as working fluids in solar collectors. [ABSTRACT FROM AUTHOR]

The research subject of this paper are natural polymer-based hydrogels modified with albumin particles. The proteins were obtained via the salt-induced precipitation method, and next characterized using dynamic light scattering (DLS), UV-Vis spectroscopy and FT-IR spectroscopy. The most favorable composition showing monodispersity and particles with a size lower than 40 nm was selected for modification of hydrogels. Such systems were obtained via the photopolymerization performed under the influence of UV radiation using diacrylate poly(ethylene glycol) as a crosslinking agent and 2-hydroxy-2-methylpropiophenone as a photoinitiator. Next, the hydrogels' swelling ability, mechanical properties, wettability and surface morphology were characterized. Moreover, FT-IR spectroscopy, incubation studies in simulated physiological liquids, pro-inflammatory activity analysis and MTT reduction assay with L929 murine fibroblasts were performed. The release profiles of proteins from hydrogels were also verified. Materials modified with proteins showed higher swelling ability, increased flexibility even by 50% and increased surface hydrophilicity. Hydrogels' contact angles were within the range 62–69° while the tensile strength of albumin-containing hydrogels was approx. 0.11 MPa. Furthermore, the possibility of the effective release of protein particles from hydrogels in acidic environment (approximately 70%) was determined. Incubation studies showed hydrogels' stability and lack of their degradation in tested media. The viability of fibroblasts was 89.54% for unmodified hydrogel, and approx. 92.73% for albumin-modified hydrogel, and such an increase indicated the positive impact of the albumin on murine fibroblast proliferation. [ABSTRACT FROM AUTHOR]

Simvastatin (SIM) particles are liposoluble drugs with large particle sizes, resulting in poor compatibility with electrospun polycaprolactone (PCL)/polyethylene glycol (PEG) nanofibers, so that part of them will be exposed to the electrospun nanofiber surface, which is easy to cause the burst release of drugs. Therefore, in this paper, stearic acid (SA) with good biocompatibility was innovatively added to increase the dispersion uniformity of SIM in the spinning solution, thus improving the performances of SIM-loaded PCL/PEG nanofiber membranes (NFMs). Accordingly, the effects of SA addition on the morphologies, mechanical properties, wettability, and drug release properties of the SIM-loaded NFMs were studied. The results showed that after SIM was dissolved in SA solution, the particle size of SIM was significantly reduced and could be evenly dispersed in the polymer spinning solution, thus obtaining the SIM-loaded composite NFMs with the best morphology and performance. [ABSTRACT FROM AUTHOR]

Despite the fact that amphiphilic block copolymers have been studied in detail by various methods both in common solvents and aqueous dispersions, their hydrodynamic description is still incomplete. In this paper, we present a detailed hydrodynamic study of six commercial diblock copolymers featuring the same hydrophilic block (poly(ethylene glycol), PEG; degree of polymerization is ca. 110 ± 25) and the following hydrophobic blocks: polystyrene, PS35-b-PEG115; poly(methyl methacrylate), PMMA55-b-PEG95; poly(1,4-butadyene), PBd90-b-PEG130; polyethylene PE40-b-PEG85; poly(dimethylsiloxane), PDMS15-b-PEG115; and poly(ɛ-caprolactone), PCL45-b-PEG115. The hydrodynamic properties of block copolymers are investigated in both an organic solvent (tetrahydrofuran) and in water micellar dispersions by the combination of static/dynamic light scattering, viscometry, and analytical ultracentrifugation. All the micellar dispersions demonstrate bimodal particle distributions: small compact (hydrodynamic redii, Rh ≤ 17 nm) spherical particles ascribed to "conventional" core–shell polymer micelles and larger particles ascribed to micellar clusters. Hydrodynamic invariants are (2.4 ± 0.4) × 10−10 g cm2 s−2 K−1 mol−1/3 for all types of micelles used in the study. For aqueous micellar dispersions, in view of their potential biomedical applications, their critical micelle concentration values and cytotoxicities are also reported. The investigated micelles are stable towards precipitation, possess low critical micelle concentration values (with the exception of PDMS15-b-PEG115), and demonstrate low toxicity towards Chinese Hamster Ovarian (CHO-K1) cells. [ABSTRACT FROM AUTHOR]

In this paper, a new aqueous two-phase extraction system(ATPES) consisting of UCON (poly(ethylene glycol-ran-propylene glycol) monobutyl ether)–NaH2PO4 was established, and four trace polycyclic aromatic hydrocarbons (PAHs: fluorene, anthracene, pyrene and phenanthrene) in water and soil were analyzed by high-performance liquid chromatography (HPLC)–ultraviolet detection. In the multi-factor experiment, the central composite design (CCD) was used to determine the optimum technological conditions. The final optimal conditions were as follows: the concentration of UCON was 0.45 g·mL−1, the concentration of NaH2PO4 was 3.5 mol·L−1, and the temperature was 30 °C. The recovery of the four targets was 98.91–99.84% with a relative standard deviation of 0.3–2.1%. Then UCON recycling and cyclic tests were designed in the experiment, and the results showed that the recovery of PAHs gradually increased in the three extractions because of the remaining PAHs in the salt phase of last extraction. The recovery of PAHs in the UCON recycling test was less than that in the extraction test due to the wastage of UCON. In addition, a two-phase aqueous extraction model was established based on the random forest (RF) model. The results obtained were compared with the experimental data, and the root mean square error (RMSE) was 0.0371–0.0514 and the correlation coefficient R2 was 96.20–98.53%, proving that the model is robust and reliable. [ABSTRACT FROM AUTHOR]

Post-consumer waste recycling is a crucial issue for building a sustainable society. However, mechanical recycling of poly(lactic acid) (PLA) often reduces the performance of the recycled material because PLA has a strong tendency to degrade during reprocessing. Therefore, it is of great interest to develop an effective recycling method to improve the mechanical performance of this material. This paper presents a one-pot melt process for turning PLA waste into a biodegradable block copolymer and its high strength and ductility composite. The process was conducted in a melt-mixer through a transesterification of PLA with poly(ethylene glycol) (PEG) or poly(propylene glycol) (PPG) as a soft component and clay as reinforcement. Effects of soft component content and sequence of clay addition on the mechanical performance of the prepared materials were focused. The results showed the successful preparation of PLA-based multiblock copolymers of high molecular weights (~100 kDa). Both virgin PLA and recycled source could serve as the starting material. PEG was more efficient than PPG in providing an intense improvement of PLA ductility. The nanocomposite of intercalated structure yielded nearly 100 times higher elongation at break (Eb = 506%) than the starting PLA (Eb = 5.6%) with high strength of 39.5 MPa and modulus of 1.4 GPa, considering the advantages of clay addition. Furthermore, the products with a broadened range of properties can be designed based on the ratio of PLA and soft component, as well as the organization and spatial distribution of clay in the copolymer matrices. [ABSTRACT FROM AUTHOR]

The use of dental composites based on dimethacrylates that have quaternary ammonium groups is a promising solution in the field of antibacterial restorative materials. This study aimed to investigate the mechanical properties and behaviors in aqueous environments of a series of six copolymers (QA:TEG) comprising 60 wt.% quaternary ammonium urethane-dimethacrylate (QAUDMA) and 40 wt.% triethylene glycol dimethacrylate (TEGDMA); these copolymers are analogous to a common dental copolymer (BG:TEG), which comprises 60 wt.% bisphenol A glycerolate dimethacrylate (Bis-GMA) and 40 wt.% TEGDMA. Hardness (HB), flexural strength (FS), flexural modulus (E), water sorption (WS), and water solubility (SL) were assessed for this purpose. The pilot study of these copolymers showed that they have high antibacterial activity and good physicochemical properties. This paper revealed that QA:TEGs cannot replace BG:TEG due to their insufficient mechanical properties and poor behavior in water. However, the results can help to explain how QAUDMA-based materials work, and how their composition should be manipulated to produce the best performance. It was found that the longer the N-alkyl chain, the lower the HB, WS, and SL. The FS and E increased with the lengthening of the N-alkyl chain from eight to ten carbon atoms. Its further extension, to eighteen carbon atoms, caused a decrease in those parameters. [ABSTRACT FROM AUTHOR]

Current research is focused on the utilization of a numerical solution of Casson cobalt ferrite nanofluid flow by taking two forms of base fluid. This investigation includes the gradual influence of nonlinear thermal radiation on the improvement of heat transfer related to the flow of nanofluids over a stretched rotating surface by the Darcy–Forchheimer law. The model constructed by a Casson nanoliquid in the boundary layer's flow is studied for its symmetric behaviour, including cobalt ferrite nanomaterials. Two base liquids named as ethylene glycol and water are considered. The rate of heat transport is examined by considering Newtonian heating conditions. By utilizing similarity transformations, a partial differential system that governs the said model has been transformed into a highly nonlinear ordinary differential system, and numerical outcomes are obtained by implementing the RK4 via shooting methodologies. All obtained results, including local skin friction coefficients and local Nusselt number, are defined and discussed in the paper. The study's findings ensure that the Casson cobalt ferrite nanofluid flowing towards a stretching plate has a unique solution: A variation of the solid volume fraction corresponds to the decrease in various values of the Casson nanofluid parameter for both type of nanofluid. Furthermore, a similar behaviour is noted for various values of the solid volume fraction, which corresponds to various values of the inertia coefficient parameter. Moreover, for the highest values of the solid volume fraction and all values of R 1 and N i taken into account, the rate of heat transfer upsurges. The data from the local skin friction coefficient (LSFC) and local Nusselt number (LNN) have been analysed using various statistical distributions, and it has been determined that both datasets generally fit the exponentiated Weibull distribution for various values of considered parameters. The findings would serve as a starting point for the manufacture of devices. [ABSTRACT FROM AUTHOR]

Numerous hydrogels made of poly-γ-glutamic acid (γ-PGA) and various cross-linkers have been explored, but only limited data on hydrogels made of γ-PGA and poly(ethylene glycol) (PEG) are available. In this study, γ-PGA, a biodegradable and edible biopolyamide, was successfully cross-linked with selected PEGs to obtain a series of hydrogels. The swelling behaviour of these hydrogels was investigated under various pH conditions. It was also found that the structure of the cross-linker (linear or branched) affected the hydrogels' swelling behaviour. In addition, in disc diffusion assay, hydrogel discs loaded with antibiotic were tested against Staphylococcus aureus and Escherichia coli. Prolonged activity of hydrogels loaded with antibiotics in comparison to paper discs containing antibiotics was observed. Moreover, the protective effect of hydrogels on entrapped probiotic cells subjected to low pH was investigated. The hydrogel swelling ratio and amount influenced the survival rate of the protected bacteria. Considering potential biomedical applications of hydrogels, cytotoxicity was evaluated towards two cell lines, MSTO and PANC 1. [ABSTRACT FROM AUTHOR]

The oxygen reduction reaction (ORR) is paid much more attention because of the high overpotential required for driving the four-electron process in the field of storage and sustainable energy conversion, including fuel cell applications. In this paper, PtCo nanoparticles encapsulated on carbon supports were prepared by a simple modified polyol method with ethylene glycol. Structural as well as electrochemical characterizations illustrated that the PtCo/C electrocatalysts had a minimum particle size of 4.8 nm, which is close to the commercial 40 wt% Pt/JM. Moreover, the electrochemical measurements indicated that ORR activity was competitive with the commercial 40 wt% Pt/JM catalyst. The synthesis method is a critical way to produce PtCo/C catalysts for use in polymer electrolyte membranes in fuel cells (PEMFCs). [ABSTRACT FROM AUTHOR]

In the current paper, a novel technique is represented to control the liquid petrochemical and petroleum products passing through a transmitting pipe. A simulation setup, including an X-ray tube, a detector, and a pipe, was conducted by Monte Carlo N Particle-X version (MCNPX) code to examine a two-by-two mixture of four diverse petroleum products (ethylene glycol, crude oil, gasoline, and gasoil) in various volumetric ratios. As the feature extraction system, twelve time characteristics were extracted from the received signal, and the most effective ones were selected using correlation analysis to present reasonable inputs for neural network training. Three Multilayers perceptron (MLP) neural networks were applied to indicate the volume ratio of three kinds of petroleum products, and the volume ratio of the fourth product can be feasibly achieved through the results of the three aforementioned networks. In this study, increasing accuracy was placed on the agenda, and an RMSE < 1.21 indicates this high accuracy. Increasing the accuracy of predicting volume ratio, which is due to the use of appropriate characteristics as the neural network input, is the most important innovation in this study, which is why the proposed system can be used as an efficient method in the oil industry. [ABSTRACT FROM AUTHOR]

This paper discusses the forced convective heat transfer characteristics of water–ethylene glycol (EG)-based Fe3O4 nanofluid and Fe3O4–MWCNT hybrid nanofluid under the effect of a magnetic field. The results indicated that the convective heat transfer coefficient of magnetic nanofluids increased with an increase in the strength of the magnetic field. When the magnetic field strength was varied from 0 to 750 G, the maximum convective heat transfer coefficients were observed for the 0.2 wt% Fe3O4 and 0.1 wt% Fe3O4–MWNCT nanofluids, and the improvements were approximately 2.78% and 3.23%, respectively. The average pressure drops for 0.2 wt% Fe3O4 and 0.2 wt% Fe3O4–MWNCT nanofluids increased by about 4.73% and 5.23%, respectively. Owing to the extensive aggregation of nanoparticles by the external magnetic field, the heat transfer coefficient of the 0.1 wt% Fe3O4–MWNCT hybrid nanofluid was 5% higher than that of the 0.2 wt% Fe3O4 nanofluid. Therefore, the convective heat transfer can be enhanced by the dispersion stability of the nanoparticles and optimization of the magnetic field strength. [ABSTRACT FROM AUTHOR]

Polysaccharides are used extensively in various industrial applications, such as food, adhesives, coatings, construction, paper, pharmaceuticals, and personal care. Many polysaccharide structures need to be modified in order to improve their end-use properties; this is mostly done through chemical reactions. In the past 20 years many enzyme-catalyzed modifications have been developed to supplement chemical derivatization methods. Typical reactions include enzymatic oxidation, ester formation, amidation, glycosylation, and molecular weight reduction. These reactions are reviewed in this paper, with emphasis placed on the work done by the authors. The polymers covered in this review include cellulosic derivatives, starch, guar, pectin, and poly(ethylene glycol). [ABSTRACT FROM AUTHOR]

The route for the preparation of cellulose nanofiber dispersions from bacterial cellulose using ethylene glycol- or glycerol-based deep eutectic solvents (DES) is demonstrated. Choline chloride was used as a hydrogen bond acceptor and the effect of the combined influence of DES treatment and ultrasound on the thermal and mechanical properties of bacterial cellulose nanofibers (BC-NFs) is demonstrated. It was found that the maximal Young's modulus (9.2 GPa) is achieved for samples prepared using a combination of ethylene glycol-based DES and ultrasound treatment. Samples prepared with glycerol-based DES combined with ultrasound exhibit the maximal strength (132 MPa). Results on the mechanical properties are discussed based on the structural investigations that were performed using FTIR, Raman, WAXD, SEM and AFM measurements, as well as the determination of the degree of polymerization and the density of BC-NF packing during drying with the formation of paper. We propose that the disordering of the BC-NF surface structure along with the preservation of high crystallinity bulk are the key factors leading to the improved mechanical and thermal characteristics of prepared BC-NF-based papers. [ABSTRACT FROM AUTHOR]

Superparamagnetic iron oxide nanoparticles are of great interest in magnetic targeted drug delivery due to their unique properties. In this paper, size-controlled superparamagnetic iron oxide nanoparticles were synthesized in an ethylene glycol/diethylene glycol (EG/DEG) binary solvent system via a facile solvothermal method. X-ray diffraction (XRD), a scanning electron microscope (SEM), and a vibrating sample magnetometer (VSM) were used to confirm that the prepared samples were superparamagnetic Fe 3 O 4 nanospheres. When the V EG / V DEG was varied from 100/0 to 80/20, 60/40, and 40/60, the average diameters of the resulting Fe 3 O 4 nanospheres were approximately 700, 500, 300, and 100 nm, respectively. In addition, the saturation magnetization ( M s ) of Fe 3 O 4 nanoparticles with a size of 100, 300, 500, and 700 nm was 72.14, 75.94, 80.28, and 85.41 emu/g, and the corresponding remanent magnetization ( M r ) was 3.34, 3.97, 3.26, and 4.28 emu/g, respectively. The relevant formation mechanisms of Fe 3 O 4 nanoparticles are proposed at the end. These superparamagnetic Fe 3 O 4 nanoparticles with high saturation magnetization may have use as targeted drug carriers. [ABSTRACT FROM AUTHOR]

This study evaluated acrylamide (AA) levels and various quality parameters in homemade fried potatoes prepared in different sizes by integrating principles from the Slow Food Movement with advanced sensor technology. To this aim, a surface plasmon resonance (SPR) sensor based on a molecularly imprinted polymer (MIP) was first developed for the determination of AA in homemade fried potatoes at low levels, and the AA levels in the samples were established. First of all, monolayer formation of allyl mercaptane on the SPR chip surface was carried out to form double bonds that could polymerize on the chip surface. AA-imprinted SPR chip surfaces modified with allyl mercaptane were prepared via UV polymerization using ethylene glycol dimethacrylate (EGDMA) as a cross-linker, N,N′-azobisisobutyronitrile (AIBN) as an initiator, and methacryloylamidoglutamicacid (MAGA) as a monomer. The prepared AA-imprinted and nonimprinted surfaces were characterized by atomic force microscopy (AFM) and Fourier transform infrared (FTIR) spectroscopy methods. The SPR sensor indicated linearity in the range of 1.0 × 10−9–5.0 × 10−8 M with a detection limit (LOD) of 3.0 × 10−10 M in homemade fried potatoes, and the SPR sensor demonstrated high selectivity and repeatability in terms of AA detection. Additionally, the highest AA level was observed in the potato sample belonging to the T1 group, at 15.37 nM (p < 0.05), and a strong and positive correlation was found between AA levels and sensory parameters, the a* value, the ΔE value, and the browning index (BI) (p < 0.05). [ABSTRACT FROM AUTHOR]

Triazine pesticide (atrazine and its derivatives) detection sensors have been developed to thoroughly check for the presence of these chemicals and ultimately prevent their exposure to humans. Sensitive coatings were designed by utilizing molecular imprinting technology, which aims to create artificial receptors for the detection of chlorotriazine pesticides with gravimetric transducers. Initially, imprinted polymers were developed, using acrylate and methacrylate monomers containing hydrophilic and hydrophobic side chains, specifically for atrazine, which shares a basic heterocyclic triazine structure with its structural analogs. By adjusting the ratio of the acid to the cross-linker and introducing acrylate ester as a copolymer, optimal non-covalent interactions were achieved with the hydrophobic core of triazine molecules and their amino groups. A maximum sensor response of 546 Hz (frequency shift/layer height equal to 87.36) was observed for a sensitive coating composed of 46% methacrylic acid and 54% ethylene glycol dimethacrylate, with a demonstrated layer height of 250 nm (6.25 kHz). The molecularly imprinted copolymer demonstrated fully reversible sensor responses, not only for atrazine but also for its metabolites, like des-ethyl atrazine, and structural analogs, such as propazine and terbuthylazine. The efficiency of modified molecularly imprinted polymers for targeted analytes was tested by combining them with a universally applicable quartz crystal microbalance transducer. The stable selectivity pattern of the developed sensor provides an excellent basis for a pattern recognition procedure. [ABSTRACT FROM AUTHOR]

Despite the appealing properties of random copolymers, the use of these biomaterials in association with phospholipids is still limited, as several aspects of their performance have not been investigated. The aim of this work is the formulation of lipid/random copolymer platforms and the comprehensive study of their features by multiple advanced characterization techniques. Both biomaterials are amphiphilic, including two phospholipids (1,2-dioctadecanoyl-sn-glycero-3-phosphocholine (DSPC), 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC)) and a statistical copolymer of oligo (ethylene glycol) methyl ether methacrylate (OEGMA) and 2-(diisopropylamino) ethyl methacrylate (DIPAEMA). We examined the design parameters, including the lipid composition, the % comonomer ratio, and the lipid-to-polymer ratio that could be critical for their behavior. The structures were also probed in different conditions. To the best of the authors' knowledge, this is the first time that P(OEGMA-co-DIPAEMA)/lipid hybrid colloidal dispersions have been investigated from a membrane mechanics, biophysical, and morphological perspective. Among other parameters, the copolymer architecture and the hydrophilic to hydrophobic balance are deemed fundamental parameters for the biomaterial co-assembly, having an impact on the membrane's fluidity, morphology, and thermodynamics. Exploiting their unique characteristics, the most promising candidates were utilized for methotrexate (MTX) loading to explore their encapsulation capability and potential antitumor efficacy in vitro in various cell lines. [ABSTRACT FROM AUTHOR]