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An exciting new class of heat transmission fluids, nanofluids, has been developed as an alternative to traditional fluids in manufacturing. Fuel cells, heat exchangers and pharmaceutical processes are just a few of the many uses for them. When compared to monofluids, the heat transmission properties of hybrid fluids are superior. These are findings used in an extensive diversity of fields, from solar energy to air conditioning. The objective of this paper is to examine how Lorentz force and chemical reaction parameters affect the characteristics of a couple stress hybrid nanofluid (Ethylene Glycol + Graphene + Copper) flow via an exponentially stretching surface. The heat transport phenomenon is studied using viscous dissipation, exponential heat source and thermal radiation parameters. Furthermore, irreversibility analysis is provided in this paper. Governing equations are transformed into a set of nonlinear ordinary differential equations using suitable similarity transformations. The bvp4c solver in MATLAB is used to solve the transformed system. Engineering parameters of interest, including skin friction coefficient, are described using bar diagrams. It has been noted that the magnetic field and volume fraction of graphene nanoparticles (ϕ1) reduce the skin friction coefficient. At 0≤ϕ1≤0.105$0 \le {\phi }_1 \le 0.105$, the skin friction coefficient decreases at a rate of 4.68187. It is observed that there is an increment in the fluid temperature with the rise in the exponential heat source parameter, and the velocity profile increases with the increase in the mixed convection parameter. It is detected that, while Eckert number (Eck$Eck$) was set to 0≤Eck≤0.7$0 \le Eck \le 0.7$, Nusselt number was reduced by 6.29239. It is noticed that, while the chemical reaction (Cr$Cr$) is set to 0≤Cr≤0.7$0 \le Cr \le 0.7$, the mass transfer rate rises at a Rate of 0.349644. It has been observed that as the Brinkmann number and magnetic field parameters increase, so does the rate of entropy production. It is also detected that as the porosity parameter increases, the fluid momentum decreases. Furthermore, increasing the couple stress parameter decreases the fluid velocity. [ABSTRACT FROM AUTHOR]

Water‐dispersible fluorescent nano‐/microspheres have been widely used as fluorescent probes in many fields. In this paper, aldehyde‐functionalized fluorescent micelles are synthesized by self‐assembly of end‐modified hyperbranched poly(m‐phenyleneethynylene‐alter‐p‐phenyleneethynylene)(hb‐PMPE). First, hb‐PMPE with ‐Br end‐groups(hb‐PMPE‐Br) is obtained by the polymerization of AB2 monomer PhBr2–C≡C–Ph–C≡CH, then the reaction of hb‐PMPE‐Br with 4‐ethynylbenzaldehyde (EBA) gives end aldehyde‐functionalized hyperbranched polymer hb‐PMPE‐CHO. Hence, hb‐PMPE‐CHO is reacted with aminooxy methoxypolyethylene glycol‐2000 (NH2O‐MPEG2000) to link poly(ethylene glycol) (PEG) chains to the ends of hb‐PMPE‐CHO with partial residual aldehyde end‐groups, resulting in aldehyde‐functionalized amphiphilic polymer hb‐PMPE‐PEG. Fluorescent micelles with aldehyde‐containing fluorescent hb‐PMPE core and PEG shell are obtained by self‐assembling hb‐PMPE‐PEG in water. The micelle diameter is determined by the PEG content in hb‐PMPE‐PEG, which can be controlled by the reaction weight ratio of NH2O‐MPEG2000/hb‐PMPE‐CHO. When the ratio of NH2O‐MPEG2000/hb‐PMPE‐CHO > 0.75/1, micelles with a diameter < 50 nm are obtained. The water dispersion of hb‐PMPE‐PEG‐1/2 micelles (28.9 nm) emits bright green fluorescence with λmax ≈ 490 nm under UV irradiation, and the emission intensity increases with increasing concentration. [ABSTRACT FROM AUTHOR]

The sluggishness of the complementary oxygen evolution reaction (OER) is reckoned as one of the major drawbacks in developing an energy‐efficient green hydrogen‐producing electrolyzer. An array of organic molecule oxidation reactions, operational at a relatively low potential, have been explored as a substitute for the OER. Glycerol oxidation reaction (GOR) has emerged as a leading alternative in this context because glycerol, a waste of biodiesel manufacturing, has become ubiquitous and accessible due to the significant growth in the biodiesel sector in recent decades. Additionally, the GOR generates several value‐added organic compounds following oxidation that enhance the cost viability of the overall electrolysis reaction. In this study, a low‐cost, room temperature operable, and energy‐efficient synthetic methodology has been developed to generate unique two‐dimensional CuO nanosheets (CuO NS). This CuO NS material was embedded on a carbon paper electrode, which showcased excellent glycerol electro‐oxidation performance operational at a moderately low applied potential. Formic acid is the major product of this CuO NS‐driven GOR (Faradaic efficiency ~80 %), as it is formed primarily via the glyceraldehyde oxidation pathway. This CuO NS material was also active for oxidizing other abundant alcohols like ethylene glycol and diethylene glycol, albeit at a relatively poor efficiency. Therefore, this robust CuO NS material has displayed the potential to be used in large‐scale electrolyzers functioning with HER/GOR reactions. [ABSTRACT FROM AUTHOR]

The construction of diverse and distinctive self‐assembled structures in water, based on the control of the self‐assembly processes of artificial small molecules, has received considerable attention in supramolecular chemistry. Cage‐like perforated vesicles are distinctive and interesting self‐assembled structures. However, the development of self‐assembling molecules that can easily form perforated vesicles remains challenging. This paper reports a lower critical solution temperature (LCST) behavior‐triggered self‐assembly property of a 4‐aminoquinoline (4‐AQ)‐based amphiphile with a tetra(ethylene glycol) chain, in HEPES buffer (pH 7.4). This property allows to form perforated vesicles after heating at 80 °C (> LCST). The self‐assembly process of the 4‐AQ amphiphile can be controlled by heating at 80 °C (> LCST) or 60 °C (< LCST). After cooling to room temperature, the selective construction of the perforated vesicles and nanofibers was achieved from the same 4‐AQ amphiphile. Furthermore, the perforated vesicles exhibited slow morphological transformation into intertwined‐like nanofibers but were easily restored by brief heating above the LCST. [ABSTRACT FROM AUTHOR]

In our prior paper, surface micelles with the core‐shell‐petal structure of the double hydrophilic block copolymer poly(N‐isopropylacrylamide)‐block‐poly[oligo(ethylene glycol) acrylate] (PNIPAM‐b‐POEGA) were successfully evaluated. In this work, ionic strength (under acidic conditions) and anion‐specificity effects (under neutral conditions) on the aggregation behavior of PNIPAM‐b‐POEGA at the air/water interface and the morphologies of its Langmuir–Blodgett (LB) films were systematically studied. Under acidic conditions, the salting‐out effect prevails over the electrostatic shielding effect, and the amide group shells with a slight protonation degree are covered up by the large POEGA petals. Under neutral conditions, the stretching degrees of POEGA blocks at low/moderate salt concentrations are close. At high salt concentrations, the isotherms gradually shift to large molecular areas in the order of the NaCl, Na2SO4, NaNO3, and NaSCN cases. The hysteresis degrees of the monolayers increase with the increase of salt concentrations due to the gradually increased interfacial stretching degree and compression‐induced underwater solubility of POEGA blocks. All the initial LB films of PNIPAM‐b‐POEGA exhibit isolated circular micelles with small cores. Upon compression, the LB films exhibit slightly large micelles because of the possible coalescence of some neighboring cores. [ABSTRACT FROM AUTHOR]

High performance copolyesters with ultrahigh glass transition temperature (Tg) are crucial in emerging technology fields such as electronic devices, automotives, and coatings. In this paper, a series of poly(ethylene bis[4‐(2‐hydroxyethoxy) phenyl] sulfone 2,6‐naphthalate) (PESNs) with high Tg are synthesized by the copolymerization of 2,6‐naphthalenedicarboxylic acid (2,6‐NDA), bis[4‐(2‐hydroxyethoxy) phenyl] sulfone (BHEBS), and ethylene glycol (EG). The chemical structure and compositions of prepared copolymers are confirmed by hydrogen nuclear magnetic spectra (1H NMR). Tg of copolyesters (121.1–152.2 °C) depends on composition and is comparable to that of polyetheretherketone (PEEK: 143 °C), increasing as the amount of BHEBS units is increased. The Fox, Gordon–Taylor, and Kwei equations are employed to evaluate the variation of Tg with respect to the composition of PESNs, respectively. In these three equations, the data calculated by Kwei equation fit the actual results best, attributed to the peculiar dielectric properties. In addition, PESNs show good solubility in 1,1,2,2‐tetrachloroethane, DMF, and DMSO, which is conducive to meet the needs of polyester coating. [ABSTRACT FROM AUTHOR]

The development of sustainable drug delivery systems is very important in the field of pharmaceutical research and has many advantages over the usual methods of drug administration, including improving effectiveness, reducing side effects, and increasing patient compliance. Among various techniques, electrospraying as a voltage‐driven process has emerged as a promising technology for the fabrication of drug‐loaded nanoparticles. In recent years, the application of electrospray approach for drug release has been widely investigated. However, optimization of electrospray process parameters and development of mathematical models to predict drug release kinetics from microparticles are still challenging. To address these issues, a combination of Central Composite Design (CCD) and Response Surface Methodology (RSM) has been used. This paper focuses on the application of CCD‐RSM for modeling and optimization of doxorubicin (DOX)‐poly(caprolactone) (PCL)‐polyethylene glycol (PEG) microparticles prepared using electrospray method. Doxorubicin, a widely used anticancer drug, exhibits potent cytotoxicity against a wide range of cancers. PCL‐PEG microparticles are promising as drug carriers due to their biocompatibility, controlled release properties, and ability to protect the encapsulated drug from degradation. The CCD‐RSM approach allows systematic investigation and optimization of several formulation and process variables, including polymer concentration, PCL‐PEG weight ratio, and applied voltage on drug release behavior. In addition, the effect of rheology and electrical conductivity of polymer fluid on the size of particles obtained from electrospraying was investigated. The effect of adding folic acid and doxorubicin in the optimized sample of nanoparticles and the effect of different concentrations of doxorubicin were investigated, and SEM, DLS, and FTIR techniques were used to characterize the microparticles, and the MMT test was performed to evaluate their cytotoxicity. The results showed that the optimized formulation is effective for sustained drug release over a long period for drug delivery applications. [ABSTRACT FROM AUTHOR]

Mathematical simulation of biological fluids is of upmost significance due to its numerous medical uses. Interpreting various biological flows necessitates a thorough knowledge of the peristaltic mechanism. This paper presents a computational study for the peristaltic pumping within vertical asymmetric channels filled with BN‐EG nanofluid under the influence of temperature‐dependent electrical conductivity and thermal radiation. Experimental study showed that the nanofluid created by suspending Boron Nitride particles in a combination of Ethylene Glycol exhibited non‐Newtonian characteristics. Further, the Carreau's fluid model provides accurate predictions about the rheological properties of BN‐EG nanofluid. Various configurations of the outer boundaries are considered, namely, square wave, multi‐sinusoidal wave, trapezoidal wave, and triangular wave. A uniform magnetic field together with nanoparticles and mass concentrations, joule heating, first‐order chemical reaction as well as viscous dissipation are considered. Influences of the Dufour and Soret numbers are examined, and the cases of biological scientific assumptions which is known as low Reynolds number and long wavelength are applied. All the computations are obtained numerically using Mathematica symbolical software (ND‐Solve), and the obtained results are presented in terms of the axial velocity u, heat transfer rate Z, concentration profile Ω, temperature profile θ, extra stress tensor Sxy${S}_{xy}$, pressure gradient dpdx$\frac{{dp}}{{dx}}$, pressure rise Δpλ${\mathrm{\Delta p}}_{{\lambda}}$ and stream function ψ. The major outcomes revealed that the maximizing in electrical conductivity coefficient, variable viscosity coefficient and magnetic field parameter is better to obtain a higher rate of the heat transfer while the increase in thermo‐diffusion effects as well as linear thermal radiation coefficient causes a reduction in the rate of heat transfer. [ABSTRACT FROM AUTHOR]

Lateral Flow Assays (LFAs) are cost‐effective and widely utilized for rapid diagnostics, yet they often suffer from limited sensitivity. This study introduces a straightforward yet highly effective method to enhance LFAs performance by integrating a poly(ethylene glycol) diacrylate (PEGDA) hydrogel to create a "reaction trap." This hydrogel reaction trap optimizes the flow rate and reaction time at the sensing components, substantially improving assay performance. By applying various hydrogel concentrations (6%, 9%, 12%, 15%, and 18% w/v), significant enhancements across a range of detection systems are achieved. An optimized 18% hydrogel concentration shows a 1.5 times increase in sensitivity in the tested commercial pregnancy test. Additionally, 12% hydrogel concentration is tested in pregnancy, ovulation, and Coronavirus disease 2019 (COVID‐19) commercial kits, and the improvement reached up to a sevenfold increase in signal intensity. The enhancement in detection illustrates the profound impact of this simple modification and shows the importance of hydrogel concentration optimization to maximize detection improvement. These results demonstrate that hydrogel‐coated LFAs offer a scalable and highly effective solution for boosting the reliability and sensitivity of rapid diagnostics across different healthcare settings, with broad potential for global health diagnostics applications. [ABSTRACT FROM AUTHOR]

A novel microwave‐assisted intercalation (MAI) strategy is proposed for fast and efficient intercalation of layered MXene to prepare large‐size single‐layer MXene. After LiF‐HCl etching of Ti3AlC2, the as‐prepared multi‐layer Ti3C2Tx (M‐T) are intercalated with Li3AlF6 as an intercalator and ethylene glycol (EG) as a solvent under microwave irradiation for 5 min. Furthermore, the dispersed high‐quality large‐sized single‐layer Ti3C2Tx (S‐T) nanosheets with a thickness of 1.66 nm and a large lateral size over 20 µm are achieved with a yield of over 60% after a further ultrasonic delamination followed by electrostatic precipitation, acid washing, and calcination. In addition, Pd/S‐T composite catalyst, which is constructed with Pd nanoparticles supported on the as‐prepared S‐T nanosheets, exhibits an excellent performance for rapid and efficient selective hydrogenation of nitroarenes with H2 under a mild condition. At room temperature, full conversion of nitrobenzene and 100% aniline selectivity are achieved over Pd/S‐T catalyst in 20 min with 0.5 MPa of H2 pressure. This work provides a novel method for facile, fast, and large‐scale preparation of single‐layer MXene and develops a new approach for constructing efficient nanocatalytic systems. [ABSTRACT FROM AUTHOR]

The general strategy for n‐type organic thermoelectric is to blend n‐type conjugated polymer hosts with small molecule dopants. In this work, all‐polymer n‐type thermoelectric is reported by dissolving a novel n‐type conjugated polymer and a polymer dopant, poly(ethyleneimine) (PEI), in alcohol solution, followed by spin‐coating to give polymer host/polymer dopant blend film. To this end, an alcohol‐soluble n‐type conjugated polymer is developed by attaching polar and branched oligo (ethylene glycol) (OEG) side chains to a cyano‐substituted poly(thiophene‐alt‐co‐thiazole) main chain. The main chain results in the n‐type property and the OEG side chain leads to the solubility in hexafluorineisopropanol (HFIP). In the polymer host/polymer dopant blend film, the Coulombic interaction between the dopant counterions and the negatively charged polymer chains is reduced and the ordered stacking of the polymer host is preserved. As a result, the polymer host/polymer dopant blend exhibits the power factor of 36.9 µW m−1 K−1, which is one time higher than that of the control polymer host/small molecule dopant blend. Moreover, the polymer host/polymer dopant blend shows much better thermal stability than the control polymer host/small molecule dopant blend. This research demonstrates the high performance and excellent stability of all‐polymer n‐type thermoelectric. [ABSTRACT FROM AUTHOR]

Cellobiose dehydrogenase (CDH) is applied as a bioelectrocatalyst in biosensors because its mobile cytochrome domain is capable of direct electron transfer. This study investigates the electron transfer mechanism of CDH molecules embedded in the polycation polyethyleneimine (PEI), which has been reported as a current‐boosting component of CDH‐based biosensors. By immobilizing different concentrations of CDH and its isolated cytochrome domain in PEI films, we found that increasing concentrations of cytochrome enhanced the film conductivity (up to 251±8 mS cm−1) through improved electron transfer between the protein redox centers. The increased electrical conductivity of the film contacts CDH molecules at a greater distance from the electrode. The cross‐linker poly(ethylene glycol) diglycidyl ether improves the packing and contacting of the cytochrome domains, whereas glutaraldehyde reduces the current obtained. Deglycosylation of CDH enhances the conductivity of enzyme‐polymer films by up to 34 %, implying a higher number of productive electron‐hopping events between cytochrome domains due to enhanced mobility or reduced shielding. By balancing negative charges on the CDH surface at neutral and alkaline pH, PEI increases the interdomain electron transfer and the electrical film conductivity. The resulting increased current output is relevant for in vivo bioanalytical applications. [ABSTRACT FROM AUTHOR]

The cell performance of Li−S batteries can be improved by establishing compatibility with the electrolyte of cathode and enhancing lithium‐ion diffusion (ionic conductivity) or electrical conductivity. In this work, we introduce cathode material based on ethylene glycol‐containing acrylic polyphosphazene. Poly[(2acrylamidoethoxy)‐random‐(methoxyethoxyethoxy)] phosphazenes were synthesized by macromolecular substitution of poly(dichloro)phosphazene with 2‐acrylamidoethanol and diethylene glycol methyl ether in two different ratios (25 and 50 mol% of ethylene glycol methyl ether), abbreviated as MP‐25EG and MP‐50EG, where ethylene glycol chains enhance the electrolyte compatibility and ion transport of the sulfur cathode material. Then, poly[S‐random‐(2acrylamidoethoxy)‐random‐(methoxyethoxyethoxy)] phosphazene polymers, designated as MP‐25EG‐xS or MP‐50EG‐xS (x=50 and 80 wt.% of sulfur) were prepared by inverse vulcanization of polymer with two feed sulfur ratios. Structural characterizations of the polymers were carried out using appropriate standard spectroscopic methods such as 1H and 31P NMR, FT‐IR, DSC and TGA as well as XPS. The electrochemical performance of MP‐25EG‐50S, MP‐25EG‐80S and MP‐50EG‐50S, MP‐50EG‐80S were evaluated and the effect of ethylene glycol was investigated by comparing cell performances. MP‐50EG‐50S demonstrated its promising applicability in Li–S batteries by exhibiting much better electrochemical respond with a discharge capacity of 745 mAh/g at C/5 current density over 100 cycles. [ABSTRACT FROM AUTHOR]

The evaporation of particle‐free silver ink droplets on heated substrates directly impacts the morphology of the resultant silver particles and electrically conductive inkjet‐printed films. In this work, COMSOL Multiphysics simulations of the droplet evaporation process are used to help explain the fluidic processes responsible for the experimental observations. The results show that the silver particle morphology depends on its location within the evaporating droplet where large particles (3 to 5 µm) accumulate at the center and smaller ones (1 to 2 µm) in the area beyond the central region. The smallest particles (≈500 nm) are near the contact line. Without the fluoro‐surfactant FS‐31, an inner ring with 3 µm particles also appears within the evaporating droplet. The large particles at the central region originate from the fluid near the droplet's apex due to the accumulation of polyacrylamide in the concentrated ethylene glycol solvent near the flow‐abundant apex. Furthermore, the capillary flow along the fluid–air interface transports silver ions and particles throughout the droplet, causing the larger particles to fall onto the substrate at the central vortex, forming the inner ring. The simulations also demonstrate that the evaporating droplet heterogeneously accumulates ethylene glycol in a sandhill formation at the bottom center. [ABSTRACT FROM AUTHOR]