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Superabsorbent polymer gels are widely used in commercial areas, such as in hygiene products. A key aspect in these and other applications is the gel swelling kinetics, and a key factor of influence on that is the hydrophobicity of the gel. This paper reports on the synthesis of superabsorbent polymer microgel particles with four differently hydrophobic crosslinkers: N,N'‐methylenebisacrylamide (MBAA), N,N'‐ethylenebisacrylamide (EBAA), N,N'‐propylenebisacrylamide (PBAA), and N,N'‐butylenebisacrylamide (BBAA). This work uses droplet‐based microfluidics to produce uniform and well‐defined microgel specimen and study the influence of the crosslinker hydrophobicity on the swelling kinetics. In particular, this work determines swelling constants and their dependencies on the temperature of the swelling medium as well as the activation energies of swelling in relation to the crosslinker hydrophobicity. This work finds two competing effects, leading to a narrow window in which the activation energy of the swelling of the microgels decreases with increasing crosslinker hydrophobicity. [ABSTRACT FROM AUTHOR]

Bone drilling in neurosurgical, dental, and orthopedic procedures, combined with the use of coolants, generates a dispersion of bone particles, coolants, and blood aerosols in the air. This poses the threat of airborne transmission of infectious diseases between patients and medical practitioners. Highly viscoelastic polymeric poly(acrylic acid) (PAA) and poly(ethylene oxide) (PEO) solutions of various concentrations were used as coolants during bone drilling at different mass flow rates to suppress aerosol generation, thereby mitigating the threat of cross-infection. The results revealed that the PAA and PEO solutions provide less advection than water and a comparable cooling performance. However, excessive viscoelasticity of PEO causes the fluid to rise along the cutting burr (the Weissenberg effect), thereby reducing the cooling coverage area. In contrast, slightly lower viscoelasticity of PEO results in a high cooling coverage area. The cooling coverage area is smaller for the PAA at 20 ml/min because the corresponding PAA solution easily swirls or splashes away from the drilling location. However, at 80 ml/min, the supplied PAA solution sufficiently cools the drilling area, despite the loss through splashing. The numbers of atomized droplets of water and the PAA and PEO solutions were quantified and compared to investigate the degree of aerosol formation and dispersion. The solution with the strongest viscoelasticity most significantly suppressed aerosolization and produced the fewest dispersed aerosol droplets during bone drilling. [ABSTRACT FROM AUTHOR]

Two approaches to the synthesis of hydrogels based on polyacrylamide (pAAm) with copolymers were compared in the paper—traditional chemical cross-linking and physical cross-linking with montmorillonite (MMT). The main aim of the work was to find an adequate replacement of the chemical toxic cross-linking agent MBAAm (N,N'-methylene-bis-acrylamide) by using non-toxic—natural clay MMT for synthesis of pAAm gels, which are planned to be used as soil conditioners. A series of hydrogels based on acrylic monomers (acrylamide (AAm), acrylonitrile (AN), acrylic acid (AA)) physically cross–linked by MMT and chemically cross-linked were synthesized. For the synthesized gels, the influence of the synthesis method on the formation of the structure and the mechanism of thermal destruction in the presence of air was analyzed using a set of physicochemical methods: FTIR, XRD, SEM, DSC and TG/DTG. According to FTIR and XRD data, pAAm-MMT and pAAm-AN-MMT samples formed an intercalated/exfoliated structure, whereas pAAm-AA-MMT had an intercalated structure. The endothermic reaction of decomposition of xerogels based on acrylic polymers with and without MMT was observed using DSC and derivative thermogravimetry analyses, coupled with measurement of FTIR spectra of volatile products of thermolysis. All studied composites were relatively thermoresistant, which had three distinct regions of phase transitions and their thermal decomposition occurred at a temperature range 310–465 °C. [ABSTRACT FROM AUTHOR]

In this work, MoVTeNbOx catalysts was doped with Cr by using spray drying method. The effect of Cr doping on the crystalline phase, physicochemical properties, and catalytic performance of selective oxidation of propane to acrylic acid of MoVTeNbOx was investigated. The results showed that the samples as-prepared by spray drying method present unique spherical morphology stacked by rod particles. In addition, Cr doping induced a change in the mesopore structure formed by rod stacking, reducing the pore radius of the catalysts from 5-10 nm to 2-4 nm. Meanwhile, Cr doping dramatically reduced the average particle size of MoVTeNbOx catalysts, decreasing the rod cross-section diameter of catalysts from 234.21 to 134.96 nm and the rod length from 1.096 μm to 485.71 nm, which significantly increased the amount of (001) active crystalline plane. Moreover, an appropriate amount of Cr doping increased the number of reducible species in the catalyst and reduced its acidity. At the same time, the surface V5+ content of the catalyst was increased from 35.8% to 72.6%. Cr-doped MoVTeNbOx with mesoporous structure showed excellent performance in catalyzing selective oxidation of propane to acrylic acid reaction. Among them, S-3 sample (V: Cr = 1:0.015) increased the selectivity and yield to acrylic acid from 67.5% to 84.3% and from 26.4% to 43.2%, respectively, at reaction temperature of 380 °C. [ABSTRACT FROM AUTHOR]

The three-dimensional imprinted polymeric network was synthesized via a bulk polymerization reaction in the presence of a flavonoid as a template. In this reaction, methacrylic acid (MAA) and acrylic acid (AA), tetrahydrofuran and trimethylolpropanetrimethacrylate, were used as functional monomers, porogen, and cross-linker, respectively. In this study, two kinds of molecularly imprinted polymers (MIPs) with different ratios of 1:8:40 and 1:20:80 (template: functional monomer: cross-linker) were synthesized and compared together. The related binding capacities were calculated as equal to 392.08 mg/g and 609.00 mg/g, respectively, by UV-spectrometer. The synthesized polymers have been evaluated via field emission scan electron microscopy, transmission electron microscopy, and Brunauer–Emmett–Teller techniques. High selectivity and the proper specific surface area as equal to 167.00 m2/g in MIPs-based methacrylic acid (MIPs-MAA) and 434 m2/g in MIPs-based acrylic acid (MIPs-AA) comparatively to non-imprinted molecular polymers are the privileged characteristics in this research. The MIPs provided are a good candidate for the separation of flavonoids with the solid phase extraction method. [ABSTRACT FROM AUTHOR]

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Copyright of Inorganic Chemicals Industry is the property of Editorial Office of Inorganic Chemicals Industry and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this study, poly(acrylic acid) (PAA) thin films were deposited on silicon wafer and glass surfaces by initiated chemical vapor deposition (iCVD) method using di-tert-butyl peroxide (TBPO) as the initiator and acrylic acid (AA) as the monomer. During iCVD, two different precursor feeding approaches, namely continuous and closed-batch, were employed. The effects of substrate temperature and the precursor feeding approaches on the deposition rates and surface morphology of the films were investigated. The highest deposition rates for the continuous and closed-batch iCVD approaches were found as 26.1 nm/min and 18.6 nm/min, respectively, at a substrate temperature of 15 ℃. FTIR analysis of the films deposited by both approaches indicated high structural retention of the monomer during the polymerization. AFM results indicated that, PAA thin films possessed low RMS roughness values of 2.76 nm and 1.84 nm using continuous and closed-batch iCVD, respectively. Due to the slightly higher surface roughness of the film deposited under continuous iCVD, that film exhibited a lower water contact angle of 16.1° than the film deposited in closed-batch iCVD. In terms of monomer utilization ratio, closed-batch system was found to be more effective, which may help to minimize the carbon footprint of iCVD process. [ABSTRACT FROM AUTHOR]

Silicon oxide (SiOx) is heralded as the forefront anode material for high‐energy density lithium‐ion batteries, owing to its exceptional specific capacity. Nevertheless, the traditional combination of polyacrylic acid binder and acetylene black conductive carbon continues to struggle with the immense stress induced by the repetitive volume expansion and contraction processes. Here we report a high ionic conductivity, sulfonyl fluoro‐containing binder for SiOx anode via free radical copolymerization reaction between perfluoro (4‐methyl‐3,6‐dioxaoct‐7‐ene) sulfonyl fluoride and acrylic acid. The electrode fabrication process incorporated amino‐functionalized carbon nanotubes (CNT‐NH2) as the conductive agent. A three‐dimensional conductive network structure is constructed through physical and chemical double cross‐linking interactions between the ‐COOH and ‐SO2F functional groups of PAF0.1 binder, the ‐NH2 groups of CNT‐NH2, and the ‐OH groups on the surface of SiOx, including hydrogen bonds and covalent bonds. In addition, the binder induces the formation of a solid electrolyte interphase (SEI) rich in inorganic components such as Li2O, Li2SO3, Li2CO3, and LiF. Benefiting from the synergistic effects of the physically and chemically double cross‐linked three‐dimensional conductive network constructed by the PAF0.1 binder and CNT‐NH2, coupled with the rich‐inorganic SEI, the SiOx anode delivers exceptional rate performance, cycle stability, and lithium‐ion diffusion dynamics. [ABSTRACT FROM AUTHOR]

New self‐healing resin composites with tertiary amine microcapsules enhance the mechanical performance of dental restorations. However, a higher concentration of dibenzoyl peroxide (BPO) must be added to the composite to react with the core material when the microcapsules rupture, reducing the shelf life of dental materials due to their reactivity. As a result, one approach to reducing the amount of BPO dissolved in dental resin is to microencapsulate it. Thus, this manuscript described the encapsulation of BPO in poly(urea‐formaldehyde) (PUF) microcapsules (MC) and investigated its effect on the flexural strength of BisGMA/TEGDMA composites. To synthesize hollow MC, poly(acrylic acid) (PAA) was tested as a continuous phase viscosity modifier. The MC were then infiltrated with BPO dissolved in linseed oil as core materials. PAA in continuous phase increased MC diameter due to improved air bubble stability. BPO dissolved in linseed oil was successfully infiltrated into empty PUF MC, causing the MC shell wall to expand. The dental resin had adequate adhesion to the PUF shell, which ruptured under induced stress. Thus, the MC filled with BPO as a healing agent has the potential to reduce the amount of BPO that is typically dissolved in the monomeric phase of dental materials, which can increase the shelf life of self‐healing dental materials. Highlights: The reactivity of dibenzoyl peroxide (BPO) affects resin stability in dental materials.When combined with tertiary amines, BPO acts as a healing agent in self‐healing composite materials.BPO dissolved in linseed oil can be infiltrated in PUF microcapsules and increase its size.Hollow microcapsules synthesized in a more viscous continuous phase have a larger diameter.Microencapsulated BPO is released during stress stimuli in dental resin. [ABSTRACT FROM AUTHOR]

Hydrogels can relieve wound pain and provide a moist environment for wound healing. Although hydrogels based on natural materials have proven to be biocompatible and biodegradable, their antibacterial and anti-inflammatory properties are not desirable. Natural extracts with antimicrobial and antioxidant properties are becoming increasingly attractive because of their environmentally friendly nature and good biocompatibility. Herein, composite cellulose/silk fibroin/polyacrylic acid hydrogels based on natural materials were fabricated by crosslinking between oxidized cellulose and silk fibroin together with radical polymerization of acrylic acid. The fabricated hydrogels displayed a uniform hierarchical topography with high porosity, as well as good mechanical properties, swelling properties, air permeability and biocompatibility. With the addition of tea polyphenols to natural extracts, the composite hydrogels exhibited significant antimicrobial and antioxidant properties such that they could prevent bacterial infection and relieve wound inflammation in the inflammation stage and could promote the synthesis of extracellular matrix (ECM), angiogenesis, collagenization and re-epithelization during wound healing. The tea polyphenols/cellulose/silk fibroin/polyacrylic acid hydrogels fabricated in this study can accelerate wound healing, demonstrating their great potential for application in wound dressings. [ABSTRACT FROM AUTHOR]

Hybrid hydrogels with superabsorbent properties based on acrylic acid (20%), sodium alginate (0.5%) and poly(ethylene oxide) (0.1%) were obtained by electron-beam irradiation between 5 and 20 kGy, and are characterized by different physical and chemical methods; the first results reported showed gel fractions over 87%, cross-link densities under 9.9 × 103 mol/cm3 and swelling degrees of 400 g/g. Two types of hydrogels (without and with 0.1% initiator potassium persulfate) have been subjected to swelling and deswelling experiments in different swelling media with different pHs, chosen in accordance with the purpose for which these superabsorbent materials were obtained, i.e., water and nutrients carriers for agricultural purposes: 6.05 (distilled water), 7.66 (tap water), 5.40 (synthetic nutrient solution) and 7.45 (organic nutrient solution). Swelling kinetics and swelling dynamics have been also studied in order to investigate the influence of swelling media type and pH on the absorption phenomenon. The swelling and deswelling behaviors were influenced by the hydrogel characteristics and pH of the swelling media. Both the polymeric chain relaxation (non-Fickian diffusion) and macromolecular relaxation (super case II) phenomenon were highlighted as a function of swelling media type. [ABSTRACT FROM AUTHOR]

Zn–air batteries (ZABs) are a promising technology; however, their commercialization is limited by challenges, including those occurring in the electrolyte, and thus, gel polymer electrolytes (GPEs) and hydrogels have emerged as substitutes for traditional aqueous electrolytes. In this work, PVA/PAA membranes were synthesized by the solvent casting method and soaked in 6 M KOH to act as GPEs. The thickness of the membrane was modified (50, 100, and 150 μm), and after determining the best thickness, the membrane was modified with synthesized SiO2 nanospheres and multi-walled carbon nanotubes (CNTs). SEM micrographs revealed that the CNTs displayed lengths of tens of micrometers, having a narrow diameter (95 ± 7 nm). In addition, SEM revealed that the SiO2 nanospheres had homogeneous shapes with sizes of 110 ± 10 nm. Physicochemical experiments revealed that SiO2 incorporation at 5 wt.% increased the water uptake of the PVA/PAA membrane from 465% to 525% and the ionic conductivity to 170 mS cm−1. The further addition of 0.5 wt.% CNTs did not impact the water uptake but it promoted a porous structure, increasing the power density and the stability, showing three-times-higher rechargeability than the ZAB operated with the PVA/PAA GPE. [ABSTRACT FROM AUTHOR]

An alternative synthetic pathway was proposed for the optimization of synthesis to find a better correlation between the swelling and elasticity of hyaluronic acid-interpenetrated gels via temperature regulation. An experimental design methodology was presented for the synthesis of polyacrylamide/poly(acrylic acid sodium salt)/hyaluronic acid, PAAm/PSA/HyA, gels by modifying the one-pot procedure using free radical crosslinking copolymerization of AAm with the addition of anionic linear PSA chains in the presence of various amount of HyA, ranging between 0.05% and 0.20% (w/v). Semi-interpenetrated polymer network (IPN)-structured gels were designed with tunable elasticity, in which the extent of covalent crosslinking interactions is controlled by polymerization temperature ranging between −18 and 45 °C. Depending on the HyA content added in the synthesis and the polymerization temperature, the swelling ratio could be controlled. The addition of 0.05% (w/v) HyA increased the swelling of semi-IPNs, while the elastic modulus increased with increasing HyA content and decreased with the polymerization temperature. PAAm/PSA/HyA semi-IPNs showed the typical pH-sensitive swelling of anionic gels, and the swelling reached a maximum at a pH of 11.2. PAAm/PSA/HyA gels were tested for the removal of methyl violet from wastewater. Adsorption kinetics were shown to be well-fitted with the pseudo-second-order model using linear and nonlinear regression analysis. With the clear relationship between increased modulus and composition, this study enabled the fine-tuning of semi-IPN interactions by varying the polymerization temperature. [ABSTRACT FROM AUTHOR]

An acrylic acid-modified epoxy phosphate resin coating was synthesized by a four-step method marked "A-B-C-D", and it was used as an efficient protective layer for steel structures. The coating exhibited good properties, mainly including water resistance (≥240 h), salt spray resistance (≥300 h), surface drying time (≤1 h), and adhesion (≥6.5 MPa). [ABSTRACT FROM AUTHOR]

A magnetic hydrogel based on xylan (X), poly (acrylic acid), and maghemite (γ-Fe2O3) named HXA-Fe2O3 was synthesized, characterized, and applied as an alternative material to remove methylene blue (MB) from aqueous media by adsorption. Maghemite was synthesized by coprecipitation method and later incorporated in the hydrogel matrix synthesized by free radical polymerization. The characterization studies included FTIR, DSC, XRD, VSM, Zeta Potential, TGA, SEM, TEM, and N2 adsorption isotherms (BET). The physicochemical characterization results confirmed the intended synthesis and showed the compositional, thermal, structural, morphological, textural, and magnetic profile of the materials. The adsorption studies included experimental design, kinetic, and isotherm. A full factorial design was employed considering the factors adsorbent dosage (g L−1), pH, and ionic strength (mmol L−1 of NaCl) for adsorption capacity and removal percentage responses. As ionic strength was not significant, a Doehlert design was employed with adsorbent dosage and pH, indicating the optimal adsorption conditions. The kinetics was well described by the PSO model, while the isotherm obeyed the Sips model. Equilibrium was attained at 60 min, and the maximum experimental adsorption capacity was up to 250.26 mg g−1 at pH 8.5, adsorbent dosage of 0.2 g L−1, and 298 K. These findings show that the magnetic hydrogel produced has great potential to be applied in the adsorption of basic molecules, such as MB. [ABSTRACT FROM AUTHOR]

Abstract This study aims to create a novel, distinct form of elastomer with superior ability to resist fire, high resistance to radiation, and resistance to environmental conditions such as temperature and solvents. This type of natural-based elastomer was prepared using carboxymethyl cellulose CMC, polyacrylic acid PAA, crosslinked with tannic acid TA. Most techniques in elastomer manufacture technologies are unfriendly and participate in increasing carbon emissions. Gamma radiation was used as a clean tool for copolymerization and crosslinking the elastomer. The irradiation dose of 5 kGy with a rate of 3.32 kGy/h was enough to produce CMC/PAA/TA elastomer. The properties of the produced elastomer were investigated by Fourier-transformed infrared spectroscopy (FT-IR), X-ray diffraction, thermal gravimetric analysis (TGA), and limiting oxygen index (LOI). CMC/PAA/TA has high resistance to solvents such as acetone, benzene, HCl, and HNO3. The tensile strength is 3.376 MPa, the elongation percent is 501.689%, and the LOI value is 30%. The produced elastomer possessed excellent gamma radiation resistance. The elastomer was exposed later to 1864 kGy of gamma radiation without showing degradation and retained its properties, as confirmed by FTIR, TGA, and mechanical properties. After investigation, it can be inferred that the produced CMC/PAA/TA elastomer exhibited outstanding properties.

A new highly effective sizing reagent based on grafted collagen copolymers has been proposed for cotton yarn. The copolymers were synthesized by reacting an aqueous solution of collagen with acrylic monomers--acrylic, matacrylic acids, and their amides in the presence of potassium persulfate. Based on Scanning electron microscopy--Energy dispersive (SEM-EDS) analysis data, the composition of the copolymers was determined. Unsaturated acids are more actively grafted onto collagen than their amides. When a polymer film is formed from a solution of a collagen copolymer with (meth)acrylic acid, microcracks appear on the surface of the sample; microcracks are absent in films of copolymers with (meth)acrylamide. Films of copolymers, especially methacrylamide, are quite flexible and contribute to a significant improvement in the properties of the yarn. The tensile strength of yarn sized with copolymers increases by 20%-65% compared to unsized yarn, and by 13%--38% compared to yarn sized with a starch solution. At the same time, the relative tensile elongation of the experimental yarn improves by 14%-58%, while this property of starch-size yarn deteriorates by 14%-22% compared to unsized yarn. The complete removal of graft copolymers from the surface of the yarn in the process of biochemical desizing using the enzyme protease is shown. Highlights * Graft copolymerization of (meth)aciylamide with collagen was carried out. * Grafting is initiated by the interaction of collagen with potassium persulfate. * The synthesized copolymers are effective sizing reagents for cotton yarn. * The copolymer with poly(meth)acrylamide forms a flexible and stable film. * The protease enzyme completely removes the size from the surface of the yarn. KEYWORDS acrylic monomer, collagen, cotton yam, graft copolymer, morphology, sizing, 1 | INTRODUCTION The preparation of cotton yarn for weaving is a technological link between the production of yarn and the production of fabric, therefore it plays a significant role [...]

The evaluation of toxicity related to polychlorinated dibenzo- p -dioxins and furans (PCDD/Fs) and dioxin-like polychlorinated biphenyls (DL-PCBs) is crucial for a comprehensive risk assessment in real-world exposure scenarios. This study employed a controlled feeding experiment to investigate the metabolic effects of dioxin-like compounds (DLCs) on laying hens via feed exposure. Diets enriched with two concentrations (1.17 and 5.13 pg toxic equivalents (TEQ)/g dry weight (dw)) were administered over 14 days, followed by 28 days of clean feed. Metabolomics analyses of blood samples revealed significant metabolic variations between PCDD/Fs and DL-PCBs exposed groups and controls, reflecting the induced metabolic disruption. Distinct changes were observed in sphingosine, palmitoleic acid, linoleate, linolenic acid, taurocholic acid, indole acrylic acid, and dibutyl phthalate levels, implying possible connections between PCDD/Fs and DL-PCBs toxic effects and energy-neuronal imbalances, along with lipid accumulation and anomalous amino acid metabolism, impacting taurine metabolism. Moreover, we identified three differential endogenous metabolites—L-tryptophan, indole-3-acetaldehyde, and indole acrylic acid—as potential ligands for the aryl hydrocarbon receptor (AhR), suggesting their role in mediating PCDD/Fs and DL-PCBs toxicity. This comprehensive investigation provides novel insights into the metabolic alterations induced by PCDD/Fs and DL-PCBs in laying hens, thereby enhancing our ability to assess risks associated with their exposure in human populations. [Display omitted] [ABSTRACT FROM AUTHOR]

In the industrial mining environment, coal dust pollution has been a persistent issue, causing harm to both human health and the ecosystem. Starch–based polymers have emerged as promising solutions for dust suppression in mines. These polymers not only effectively control dust dispersion but also offer environmental benefits. Derived from natural sources and biodegradable, starch–based polymers align with sustainability concerns in resource extraction industries. Their ability to bond with coal dust particles improves air quality and safety for workers and communities. Sustainable practices are essential to mitigate the environmental and health impacts of coal mining despite its importance in global energy production. The thesis research focused on creating an environmentally friendly dust suppressant gel, CSS-g-AA-AEO 0.04%, to tackle the ongoing problem of coal dust pollution in mining environments. The researchers combined cassava starch with acrylic acid using graft copolymerization techniques to yield the innovative CSS-g-AA gel. Structure tests using x-ray diffraction and infrared spectroscopy (IR) clearly showed that the grafting process was successful, indicating that the gel was flexible and could be used for various applications. Extensive research efforts, including simulations, precise surface tension measurements, and comprehensive contact angle analyses, led to the identification of a surfactant with exceptional wetting properties, a 0.04% AEO surfactant. scanning electron microscope (SEM) and EDS analyses showed that the dust suppressant had good adhesion and adsorption effects on coal. The water retention capability exhibited an evaporation percentage of 90.94%, whereas wind erosion control achieved a lower dust suppression of 16.2%. This difference is of particular significance, especially under challenging high wind conditions. Incorporating starch solidification within the gel further bolstered its efficacy as a sustainable solution for coal dust suppression, emphasizing its potential as a game-changing approach to combating coal dust pollution while advocating for sustainable mining practices. These groundbreaking findings underscore the immense promise and viability of CSS-g-AA-AEO 0.04% as a cutting-edge, environmentally conscious strategy to mitigate coal dust pollution and promote sustainable mining practices for a cleaner and healthier environment. [ABSTRACT FROM AUTHOR]

A new separation technology, three-phase crystallization (TPC), was utilized to purify acrylic acid (AA) from a binary liquid mixture comprising AA and propionic acid (PA). The solid–liquid equilibrium data of AA/PA mixture reported in the literature were adopted to recover the activity coefficients of the liquid mixture; and, subsequently, the vapor–liquid equilibrium conditions of AA/PA mixture were predicted using Raoult's law and the Wilson equations for the recovered activity coefficients. The reported solid–liquid equilibrium data and the predicted vapor–liquid equilibrium conditions were coupled to determine the three-phase transformation conditions of AA/PA mixture, which were employed to conduct the batch TPC experiments. Upon conclusion of the TPC, the yield and purity were measured to estimate the amount of the AA crystals and volume of the liquid mixture retained in the overall final product, respectively. [ABSTRACT FROM AUTHOR]

Abstract Cadmium is a highly toxic metal, and its presence can have adverse effects on both human health and aquatic ecosystems. The efficient removal of cadmium from wastewater is therefore of crucial importance, but traditional methods have proved to be inadequate. Thus, technologies for the treatment of wastewater containing cadmium, including adsorption, have been developed. The aim of this study was the preparation of a polymeric material by the grafting reaction of κ-carrageenan and its use as an adsorbent for cadmium removal. This was performed to study the removal capacity of cadmium ions in synthetic solutions, as well as the effects of pH and ions on adsorption capacity, adsorption kinetics, isotherms, and reusability. Additionally, the disinfectant potential of the solution was evaluated for the inactivation of total coliforms and E. coli in river water. The best adsorption capacity was 75.52 ± 1.325 mg g−1, with the kinetics described by the pseudo-second order model. Maximum adsorption capacity (127.6 ± 1.833 mg g−1) and RL (0.0113) were determined using the Langmuir model, the Freundlich model was the one that best fits the experimental data and indicated cooperative adsorption, and the Dubinin-Radushkevich isotherm was used to obtain the adsorption energy and identify that it is physical. The presence of ions K+, Na+, Mg2+, and Ca2+ in a concentration of 0.5% decreased the adsorption capacity, and that at pH 2.0, the adsorption capacity was drastically reduced. The study indicates that the polymer has potential as an adsorbent for removing cadmium from aqueous solutions and exhibits self-disinfecting properties.

Objective To investigate the effects of polybutylene terephthalate(PBT) grafted with various monomers, such as acrylic acid(AA), acrylamide(AM), sodium styrene sulfonate(SSS), AA+ AM and AA+ SSS on platelet adhesion and function. Methods The AA, AM, SSS, AA+ AM, and AA+ SSS were grafted onto the surface of PBT by γ-ray irradiation, and the grafted PBT was characterized by fourier transform infrared spectrometry(FTIR) and wetting time. Platelet activation and aggregation of different monomers grafted with PBT were observed by scanning electron microscopy(SEM). Platelet concentration, maximum aggregation ability, positive expression rate of CD62p and hypotonic shock rate(HSR)of PBT grafted with different monomers were tested to study their effect on platelet adhesion and function. Results The characteristic absorption peaks of AA, AM and SSS appeared in FTIR, and the hydrophilicity of the grafted material was improved obviously, indicating that the monomer was grafted successfully. The results of SEM showed that the degree of platelet activation and aggregation caused by the original PBT was significantly higher than that of modified ones. Compared with the original platelets, the platelet concentration of PBT was(533.00±4.58 vs 672.00±3.61)×109/L, the maximum platelet aggregation rate was(48.80±0.96 vs 58.60±1.37)%, the positive expression rate of CD62p was(45.35±0.58 vs 39.90±0.52)%, and the platelet HSR was(48.74±0.46 vs 51.86±0.93)%(P

MoV‐based composites stand out as the most promising potential catalysts targeted for direct production of acrylic acid from alkane/alkene substances. Herein, MoVTeNbO powder was synthesized and successfully fabricated by adding graphite as an appropriate tableting agent. Without employing graphite as lubricant, the fabrication of tablets was not practicable. The physicochemical effects of graphite on the catalyst properties were investigated via characterization by X‐ray diffraction (XRD), Brunauer–Emmett–Teller (BET), scanning electron microscopy (SEM), ammonia temperature‐programmed desorption (NH3‐TPD), and thermal gravimetric analysis (TGA) methods. In addition to the easy and operative formation of tablets by consisting graphite, TGA results indicated better thermal stability compared to the bare powder. No harmful impact of graphite on the catalyst crystalline phases and morphology was detected by XRD and SEM analysis. The SEM images proved the graphite incorporation as a binder in the physical combination of the catalyst particles along the compression process, resulting in the desired physical resistance. Graphite caused a slight decrease in the BET surface area and final catalyst acidity. Despite the effect of reducing propene conversion, interestingly, a substantial improvement in the yield of acrylic acid was found by tableting. The graphite as an inert agent suppressed hot spots on the catalyst surface, leading to superior consistency in activity over time as well as lower selectivity to undesirable COx. [ABSTRACT FROM AUTHOR]

We present a straightforward, catalyst- and additive-free method for synthesizing keto γ-butyrolactones using readily available β-keto sulfoxonium ylides and acrylic acids. This robust approach demonstrates exceptional compatibility with various functional groups on β-keto sulfoxonium ylides and α-substituted acrylic acids, resulting in good to high yields of the anticipated products. Moreover, the practicality of this approach was validated through large-scale reactions and the successful conversion of some synthesized derivatives into bioactive natural products, including L-factor, muricatacin, and cytosporanone A. [ABSTRACT FROM AUTHOR]

A prerequisite for the development or optimization of heterogeneous catalysts is a comprehensive understanding of the reaction mechanism and kinetics at the level as elementary as possible. In comparison with steady‐state catalytic tests typically used for this purpose, non‐steady‐state (transient) studies provide deeper insights due to higher time resolution. For several decades, temporal analysis of products (TAP) and steady‐state isotopic transient kinetic analysis (SSITKA) have been successfully applied to the analysis of various heterogeneous reactions. In this review, we highlight the contributions made by TAP and SSITKA studies between 2017 and 2023 to the understanding of reaction mechanisms and to the derivation of microkinetics. The versatility of these methods is illustrated by the examples of oxidative coupling of methane, CO/CO2 hydrogenation to hydrocarbons or methanol, metathesis of ethylene with 2‐butenes to propene, acrolein oxidation to acrylic acid, methanol conversion to olefins and non‐oxidative propane dehydrogenation to propene. We also provide our personal views on possible developments in this area. [ABSTRACT FROM AUTHOR]

Background Objectives Materials and Methods Results Conclusions Acrylate polymers and cross‐polymers (ACPs) are frequently used cosmetic ingredients. The British Society for Cutaneous Allergy (BSCA) and the UK Cosmetic, Toiletry and Perfumery Association (CTPA) collaborated to investigate the allergenic potential of three commonly‐used ACPs.The objective of this study is to determine the prevalence of allergic contact dermatitis (ACD) to three ACPs: glyceryl acrylate/acrylic acid co‐polymer, sodium polyacrylate, and acrylates/C10‐30 alkyl acrylate cross‐polymer (Carbopol®).The BSCA prospectively audited data collected from 20 centres in the UK and Ireland between 1st September 2021 and 1st September 2022. Patients with suspected ACD to (meth)acrylates, with facial dermatitis, or consecutive patients, were patch tested to glyceryl acrylate/acrylic acid co‐polymer 10% aqueous (aq.) sodium polyacrylate 2% aq., and to acrylates/C10‐30 alkyl acrylate cross‐polymer 2% aq. (Carbopol®). The frequencies of positive, irritant, and doubtful reactions were recorded.In total, 1302 patients were patch tested. To glyceryl acrylate/acrylic acid co‐polymer, there was one doubtful reaction in a patient allergic to multiple (meth)acrylates, and one irritant. To sodium polyacrylate, there were four irritant reactions, one doubtful, and one positive reaction; in all cases, relevance was unknown and there was no demonstrable (meth)acrylate allergy. There were no reactions to Carbopol®.Sensitisation to these concentrations of the three tested ACPs is rare. Elicitation of dermatitis in (meth)acrylate‐sensitised patients by exposure to these three ACPs appears unlikely. [ABSTRACT FROM AUTHOR]

This study investigated the adsorption of Oxytetracycline (OTC) from pharmaceutical wastewater using a kappa carrageenan based hydrogel (KPB). The aim of the present study was to explore the potential of KPB for long-term pharmaceutical wastewater treatment. A sustainable adsorbent was developed to address oxytetracycline (OTC) contamination. The hydrogel's structural and adsorption characteristics were examined using various techniques like Scanning Electron Microscope (SEM), Fourier Transform Infrared (FTIR), X-ray powder diffraction (XRD), and kinetic models. The results revealed considerable changes in the vibrational modes and adsorption bands of the hydrogel, suggesting the effective functionalization of Bentonite nano-clay. Kappa carrageenan based hydrogel achieved the maximum removal (98.5%) of OTC at concerntration of 40 mg/L, pH 8, cotact time of 140 min and adsorbent dose of 0.1 g (KPB-3). Adsorption of OTC increased up to 99% with increasing initial concentrations. The study achieved 95% adsorption capacity for OTC using a KPB film at a concentration of 20 mg/L and a 0.1 g adsorbent dose within 60 min. It also revealed that chemisorptions processes outperform physical adsorption. The Pseudo-Second-Order model, which emphasized the importance of chemical adsorption in the removal process, is better suited to represent the adsorption behavior. Excellent matches were found that R2 = 0.99 for KPB-3, R2 = 0.984 for KPB-2 and R2 = 0.989 for KPB-1 indicated strong chemical bonding interactions. Statisctical analysis (ANOVA) was performed using SPSS (version 25) and it was found that pH and concentration had significant influence on OTC adsorption by the hydrogel, with p-values less than 0.05. The study identified that a Kappa carrageenan-based hydrogel with bentonite nano-clay and polyvinyl alcohol (PVA) can efficiently remove OTC from pharmaceutical effluent, with a p-value of 0.054, but weak positive linear associations with pH, temperature, and contact time. This research contributed to sustainable wastewater treatment and environmental engineering. [ABSTRACT FROM AUTHOR]

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A temperature/pH dual‐sensitive hydrogel was prepared through simple solution radical polymerization. A novel temperature/pH dual‐sensitive terpolymerized semi‐interpenetrating network, P(NIPAAm‐co‐AA‐co‐HEAA)/SA hydrogel, was synthesized using interpenetrating network technology (IPN) with sodium alginate (SA) as the raw material. The temperature‐sensitive monomer N‐isopropylacrylamide (NIPAAm), the pH‐sensitive monomer acrylic acid (AA), and the hydrophilic monomer N‐hydroxyethylacrylamide (HEAA) were incorporated into the structure. The structure and morphology of the hydrogels were investigated using FTIR, TGA and SEM. Additionally, the swelling properties, as well as temperature and pH sensitivity, were examined. The results showed that the content of HEAA and SA influenced the swelling properties of the gels. The gels exhibited distinct swelling behaviors at different temperatures and pH levels, demonstrating remarkable temperature and pH sensitivity. Moreover, it shows rapid response speed and efficient recovery, making them suitable for use as anticancer drug carriers that meet specific requirements. [ABSTRACT FROM AUTHOR]

The design of admirable hydrogel networks is of both practical and fundamental importance for diverse applications of hydrogels. Herein a general strategy of acid‐assisted training is designed to enable multiple improvements of conventional poly (sodium acrylate) networks for hydrogels. Hydrophobic homogeneous crosslinked poly (sodium acrylate) hydrogels are prepared to verify the strategy. The multiple improvements of poly (sodium acrylate) networks are simply achieved by immersing the hydrogel networks into 4 M H2SO4 solutions. The introduced acids would induce transformation of poly (sodium acrylate) into poly (acrylic acid) at hydrogel surface, which constructs dynamic hydrogen bonding interactions to tighten the network. The acid‐containing poly (sodium acrylate) hydrogels newly generate anti‐swelling and self‐healing performance, and show mechanical improvement. The internal poly (sodium acrylate) of the pristine acid‐containing hydrogels is further fully transformed via acid‐infiltration after following cyclic stretch/release training to significantly improve the mechanical performance. The Young's modulus, stress, and toughness of the fully‐trained hydrogels are 187.6 times, 35.6 times, and 5.4 times enhanced, respectively. The polymeric networks retain isotropic in fully‐trained hydrogels to ensure superior stretchability of 8.6. The acid‐assisted training performance of the hydrogels can be reversibly recovered by NaOH neutralization. The acid‐assisted training strategy here is general for poly (sodium acrylate) hydrogels. [ABSTRACT FROM AUTHOR]

The corrosion resistance of cement–water-glass dual-liquid slurry is poor. Improving its material properties is necessary. In this study, we examined the influence of water-based lotions on the fluidity, gelling time, and mechanical properties of a cement–water-glass dual-liquid slurry based on the mix proportion of the dual-liquid slurry commonly used in construction. The mixture ratio of a C-S (cement–water-glass slurry) dual-liquid slurry was adjusted by introducing a waterborne polyurethane lotion and a waterborne acrylic lotion to modify the traditional C-S dual-liquid slurry material. When acrylic acid is used as a modifying polymer at a dosage of 7.5%, the flowability and gelation time of the dual-liquid slurry are excellent, the compressive strength of the stone body decreases slightly, the flexural strength is improved to a certain extent, and the stone body's crack resistance during water loss is also enhanced. Moreover, the porosity of the stone body is low. [ABSTRACT FROM AUTHOR]

In this paper, N-vinylpyrrolidone was copolymerized with acrylic acid and itaconic acid by free radical polymerization, and a series of polyacrylic acid-co-itaconic acid-co-N-vinylpyrrolidone (PAIN) dispersants with different pyrrolidone ligand contents were synthesized and characterized. Then, the cobalt blue nano-pigment slurry (20 wt%) was prepared through a water-based grinding method, and the optimum grinding technology was explored and determined as follows: PAIN2 as a dispersant, a dispersant dosage of 10 wt%, and a grinding time of 480 min. According to this optimum grinding technology, the prepared pigment slurry had a significantly decreased agglomeration, the D90 of which was 82 nm, and separately increased to 130 nm and 150 nm after heat storage for 3 and 7 days, exhibiting excellent heat storage stability. Additionally, its TSI value was also the lowest (1.9%), indicating good dispersion stability. The QCM and adorption capacity measuring results showed PAIN2 had a larger adsorption capacity, and the formed adsorption layer had a higher rigidity and was not easy to fall off. This was caused by both the interaction of carboxyl groups and the pyrrolidone ligand (strong coordination interaction) in PAIN2 with cobalt blue. The XPS and FT–IR measurements further proved the above-mentioned adsorption mechanism. [ABSTRACT FROM AUTHOR]

Photocatalytic membranes are crucial in addressing membrane fouling issues. However, the grafting amount of the catalyst on the membrane often becomes a key factor in restricting the membrane's self-cleaning capability. To address the challenge, this manuscript proposes a method for solving membrane fouling, featuring high grafting rates of bismuth oxide (Bi2O3) and acrylic acid (AA), significant contaminant degradation capability, and reusability. A highly photocatalytic self-cleaning microfiltration membrane made of polyvinylidene fluoride bismuth oxide and acrylic acid (PVDF-g-BA) was prepared by attaching nano Bi2O3 and acrylic acid onto the polyvinylidene fluoride membrane through adsorption/deposition and UV grafting polymerization. Compared with pure membranes and pure acrylic grafted membranes (PVDF-g-AA), the modified membrane grafted with 0.5% bismuth oxide not only improves the grafting rate and filtration performance, but also has higher self-cleaning ability. Furthermore, the degradation effect of this membrane on the organic dye methyl violet 2B under visible light irradiation is very significant, with a degradation rate reaching 90% and almost complete degradation after 12 h. Finally, after repeated filtration and photocatalysis, the membrane can still significantly degrade contaminants and can be reused. [ABSTRACT FROM AUTHOR]

Polyacrylamide (PAM) is a high-molecular-weight polymer with extensive applications. However, the inefficient natural degradation of PAM results in environmental accumulation of the polymer. Biodegradation is an environmentally friendly approach in the field of PAM treatment. The first phase of PAM biodegradation is the deamination of PAM, forming the product poly(acrylic acid) (PAA). The second phase of PAM biodegradation involves the cleavage of PAA into small molecules, which is a crucial step in the degradation pathway of PAM. However, the enzyme that catalyzes the degradation of PAA and the molecular mechanism remain unclear. Here, a novel monooxygenase PCX02514 is identified as the key enzyme for PAA degradation. Through biochemical experiments, the monooxygenase PCX02514 oxidizes PAA with the participation of NADPH, causing the cleavage of carbon chains and a decrease in the molecular weight of PAA. In addition, the crystal structure of the monooxygenase PCX02514 is solved at a resolution of 1.97 Å. The active pocket is in a long cavity that extends from the C-terminus of the TIM barrel to the protein surface and exhibits positive electrostatic potential, thereby causing the migration of oxygen-negative ions into the active pocket and facilitating the reaction between the substrates and monooxygenase PCX02514. Moreover, Arg10-Arg125-Ser186-Arg187-His253 are proposed as potential active sites in monooxygenase PCX02514. Our research characterizes the molecular mechanism of this monooxygenase, providing a theoretical basis and valuable tools for PAM bioremediation. [ABSTRACT FROM AUTHOR]

Many diseases exhibit circadian fluctuation, including diabetes, asthma, rheumatoid arthritis, and hypertension. These disorders cannot be effectively treated with conventional dosage forms and instead require time-scheduled drug release for pharmacological effectiveness. The objective of this work was to use simple process to overcome the solubility problem by employing a novel solubilizer and to generate peristaltic release based on the physical and chemical interactions between acrylic copolymer and organic acid. To address the solubility issue of nifedipine, sepitrap 4000 is being used as a solubilizer inside the core tablet. The resulting physical mixture underwent various analyzes including saturated solubility, in-vitro dissolution, FTIR, DSC, and PXRD. A saturation solubility analysis confirmed 368% improvement as significant impact of sepitrap 4000 on nifedipine solubility and bioavailability. The 32 complete factorial design was used to optimize press-coated pulsatile formulation, with lag time and time required to release 50% of drug, as responses and concentrations of eudragit RSPO and tartaric acid as independent variables. According to stability study, developed pulsatile product was found to be suitably stable under rapid and regulated settings. As a result, produced pulsatile tablet is suitable formulation for alleviation of early morning blood pressure spikes and other cardiac problems that follow a circadian rhythm. [ABSTRACT FROM AUTHOR]

Biomass‐based hydrogels can be used as the adsorbents in sewage water, as they have good adsorption capacity for heavy ions and dyes. A ternary‐grafted starch‐based hydrogel, St1.0/CMC0.5/P(AM3.0‐AA5.0‐AMPS1.0), was prepared using cornstarch (St) and sodium carboxymethyl cellulose (CMC) as raw materials, with acrylamide (AM), acrylic acid (AA), and 2‐acrylamido‐2‐methylpropane sulfonic acid (AMPS) as graft monomers. Due to the introduction of CMC and AMPS, the number and type of effective adsorption functional groups in the St1.0/CMC0.5/P(AM3.0‐AA5.0‐AMPS1.0) hydrogel increased, leading to an improved adsorption capacity and removal rate for methylene blue (MB). The maximum adsorption capacity and removal rate for MB could be 1624.49 mg/g and 91.8 %, respectively, at 25 °C. According to the adsorption isotherm and adsorption kinetics, the MB adsorption process on the hydrogel occurs according to the Langmuir isotherm model and quasi‐second‐order kinetics via a chemisorption process occurring on the adsorbent monolayer. Moreover, the St1.0/CMC0.5/P(AM3.0‐AA5.0‐AMPS1.0) hydrogel displayed good regeneration performance. The removal rate for MB could still achieve 84.3 % after the hydrogel was reused four times. [ABSTRACT FROM AUTHOR]

AbstractConventional wound dressings used in trauma treatment have a single function and insufficient adaptability to the wound environment, making it difficult to meet the complex demands of the healing process. Stimuli-responsive hydrogels can respond specifically to the particular environment of the wound area and realize on-demand responsive release by loading active substances, which can effectively promote wound healing. In this paper, BC/PAA-pH responsive hydrogels (BPPRHs) were prepared by graft copolymerization of acrylic acid (AA) to the end of the molecular chain of bacterial cellulose (BC) network structure. Antibacterial pH-responsive ‘smart’ dressings were prepared by loading curcumin (Cur) onto the hydrogels. Surface morphology, chemical groups, crystallinity, rheological, and mechanical properties of BPPRHs were analyzed by different characterization methods. The drug release behavior under different physiological conditions and bacteriostatic properties of BPPRH-Cur dressings were also investigated. The results of structural characterization and performance studies show that the hydrogel has a three-dimensional mesh structure and can respond to wound pH in a ‘smart’ drug release capacity. The drug release behavior of the BPPRH-Cur dressings under different environmental conditions conformed to the logistic and Weibull kinetic models. BPPRH-Cur displayed good antimicrobial activity against common pathogens of wound infections such as E. coli, S. aureus, and P. aeruginosa by destroying the cell membrane and lysing the bacterial cells. This study lays the foundation for the development of new pharmaceutical dressings with positive health, economic and social benefits. [ABSTRACT FROM AUTHOR]

The preparation of high‐performance and fire‐safe electrolytes for flexible quasi‐solid‐state supercapacitors is challenging. In this work, a novel fire‐safe and multifunctional deep eutectic solvent gel (DESG) is fabricated using acrylic acid and urea as hydrogen bond donors and choline chloride as a hydrogen bond acceptor. DESG shows a high ionic conductivity (0.552 S m−1), good electrochemical performance (specific capacitance: 106.8 F g−1), and a wide operating temperature range (−20–90 °C), being a promising candidate for flexible solid‐state supercapacitors. Furthermore, it exhibits a good thermoelectric conversion capability (Seebeck coefficient: 1.56 mV K−1), being ideal for thermoelectric capacitors and fire‐warning sensors. The prepared DESG rapidly self‐extinguishes after removal from fire, reaching a limiting oxygen index value of 38.0% and demonstrating its excellent flame retardancy. In addition, DESG has a good self‐healing performance (healing efficiency of 84.3%). The work provides new insights into the preparation and application of high fire‐safety and multifunctional eutectogels for flexible quasi‐solid‐state supercapacitors. [ABSTRACT FROM AUTHOR]

Feed spacers improve mixing and mass transfer in membrane modules. However, they also lead to foulant deposition in the vicinity of the spacer surface. In this paper, two hydrophilic monomers, namely, acrylic acid (AA) and 2‐hydroxyethyl methacrylate (HEMA), are respectively coated on the surface of a commercial feed spacer via a plasma‐enhanced chemical vapor deposition (PECVD) method. The resulting modified spacers are then evaluated alongside with a reverse osmosis (RO) membrane for its solute rejection, water permeability, and antifouling properties. Results show that the surface hydrophilicity of feed spacers has been enhanced upon the AA and HEMA deposition. During filtration test, the HEMA‐modified spacer demonstrates higher flux recovery rate (94.17%) and salt rejection (95.78%) for the RO membrane. In contrast, the membrane with the unmodified spacer only shows 89.44% and 92.46%, respectively. Additionally, the membrane with the HEMA‐modified spacer has a thinner fouling layer (200 nm) compared to the unmodified spacer (700 nm). The HEMA‐coated spacer outperforms all the tested spacers, demonstrating that feed spacer modification with a hydrophilic monomer via the PECVD method can effectively reduce membrane fouling. [ABSTRACT FROM AUTHOR]

Fully negatively-charged (FNC) layer-by-layer nanofilms were successfully assembled on a living cell surface for the first time using only poly(acrylic acid) (PAA) by introducing strain-promoted click chemistry to crosslink PAA layers. The resulting nanofilms retained their negative charges and showed higher adsorption of positively-charged molecules without affecting the cell viability. [ABSTRACT FROM AUTHOR]

The polymer of sodium lignosulfonate and acrylic acid was prepared by grafting copolymerization, and lignin hydrogel was obtained by the polymer intercalated with montmorillonite, and the adsorption performance of Zn (II) by lignin hydrogel was investigated. The results showed that the prepared hydrogels have good adsorbability of Zn (II) and pH response. The adsorption capacity reached 285.39 mg/g, under the initial solution concentration of 600 mg/L, pH =4.5, adsorption temperature of 45 °C and adsorption time of 140 min, respectively. Modeling of adsorption kinetics indicated good agreement of experimental data with the quasi-second-order kinetic model. Langmuir equilibrium isotherm fitted the experimental data reasonable well, the adsorption is monolayer adsorption. [ABSTRACT FROM AUTHOR]

In the present study, the novel environmental-friendly adsorbent (PAA-g-CMCDAS) obtained from carboxymethyl chitosan (CMC), dialdehyde starch (DAS) and polyacrylic acid (PAA) is used for removing silver ion. The adsorbent characterized by XRD, SEM, TGA, BET and FTIR, was evaluated for removal of silver ion from aqueous solution. The adsorption process of silver ions conformed to Langmuir isotherm and the second-order kinetic mode. The maximum adsorption capacity for silver ions was 404.77 mg·g−1, and the maximum removal efficiency was 95.05%. Also, the reusability and selectivity of PAA-g-CMCDAS was investigated, and the adsorption amount was still 388.77 mg·g−1 and the removal efficiency was up to 91.29% after five times recycle; the removal efficiency of silver ions in mixed metal ions solution was 24.24% with the total removal efficiency of mixed metal ions 58%. Therefore, PAA-g-CMCDAS was an excellent silver ion adsorbent with good reusability. [ABSTRACT FROM AUTHOR]

The list of standard abbreviations for JDS is available at adsa.org/jds-abbreviations-24. Nonstandard abbreviations are available in the Notes. Dietary methane (CH 4) mitigation is in some cases associated with an increased hydrogen (H 2) emission. The objective of the present study was to investigate the acute and short-term effects of acceptors for H 2 (fumaric acid, acrylic acid, or phloroglucinol) supplemented via pulse-dosing to dairy cows fed CH 4 mitigating diets (using nitrate or 3-nitrooxypropanol), on gas exchange, rumen gas, and VFA composition. For this purpose, 2 individual 4 × 4 Latin square experiments were conducted with 4 periods of 3 d (nitrate supplementation) and 7 d (3-nitrooxypropanol supplementation), respectively. In each study, 4 rumen-cannulated Danish Holstein cows were used. Each additive for CH 4 mitigation was included in the ad libitum–fed diet within the 2 experiments (exp. 1 and exp. 2), to which the cows were adapted for at least 14 d. Acceptors for H 2 were administered twice daily in equal portions through the rumen fistula immediately after feeding of the individual cow. In exp. 1 (nitrate), the treatments were CON-1 (no H 2 -acceptor), FUM-1 (fumaric acid), ACR-1 (acrylic acid), and FUM+ACR-1 (50% FUM-1 + 50% ACR-1). In exp. 2 (3-nitrooxypropanol), the 3 treatments, CON-2, FUM-2, and ACR-2, were similar to CON-1, FUM-1 and ACR-1 treatments, however the fourth treatment was PHL-2 (phloroglucinol). Gas exchanges were measured in respiration chambers, and samples of rumen liquid and headspace gas were taken in time series relative to feeding and dosing on specific days. Headspace gas was analyzed for gas composition, and rumen liquid was analyzed for VFA composition and dissolved gas concentrations. Headspace gas composition and dissolved gas concentration were only measured in exp. 2. Dry matter intake was reduced upon acrylic acid supplementation. There were no significant effects of any treatments in any experiments on H 2 emission, except for a decrease in hourly H 2 emission rate (g/h) at 1 h after feeding in both experiments. In exp. 2, H 2 headspace proportions increased with ACR-2 supplementation, whereas dissolved concentrations were unaffected. In exp. 1, cows on ACR-1 increased propionate proportion at 1 h after feeding. In exp. 2, both FUM-2 and ACR-2 increased rumen propionate proportion in the hours after feeding and dosing. There was no effect on rumen acetate for cows on PHL-2. There was a strong positive correlation between rumen dissolved CH 4 and headspace CH 4 (r = 0.84), whereas the equivalent correlation was weaker for H 2 (r = 0.41). For the relationship between dissolved concentrations and emissions of CH 4 and H 2 , there was a moderate positive correlation for CH 4 (r = 0.54), whereas it was weak for H 2 (r = 0.28) with zero slope. In conclusion, the results suggested that fumaric acid and acrylic acid to some extent was reduced to propionate without associative effects on measures for H 2 redirection. Furthermore, phloroglucinol seemed not to be metabolized in the rumen in the present study, because no effects on rumen acetate or measures of H 2 were observed. Changes in H 2 headspace and emission may be a poor proxy for actual changes in the rumen fluid concentration of H 2. [ABSTRACT FROM AUTHOR]

Background: Obesity, defined as excessive or abnormal body fat accumulation, which could significantly increase the risk of cardiovascular disease, type 2 diabetes mellitus (T2DM) diseases and seriously affect people's quality of life. More than 2 billion people are overweight, and the incidence of obesity is increasing rapidly worldwide, it has become a widely concerned public health issue in the world. Diverse evidence show that active metabolites are involved in the pathophysiological processes of obesity. Aims: However, whether the downstream catabolite of tryptophan, 3-indole acrylic acid (IA), is involved in obesity remains unclear. Methods: We collected the samples of serum from peripheral blood of obesity and health controls, and liquid chromatography–mass spectrometry (LC-MS) was performed to identify the plasma levels of IA. Additionally, we verified the potential benefits of IA on human preadipocytes and HFD- induced zebrafish by cell viability assay, flow cytometry assay, Oil red O staining, total cholesterol (T-CHO), triglyceride (TG) and nonesterified free fatty acids (NEFA) measurements and Nile Red staining. RNA-Seq, functional analysis and western blot revealed the mechanisms underlying the function of IA. Results: We found that the content of IA in peripheral blood serum of overweight people was significantly lower than that of normal people. In addition, supplementation with IA in zebrafish larvae induced by a high fat diet (HFD) dramatically reduced HFD induced lipid accumulation. IA had no effect on proliferation and apoptosis of preadipocytes, but significantly inhibited adipogenesis of preadipocytes by down-regulate CEBPα and PPARγ. RNA-Seq and functional analysis revealed that IA regulated the adipogenesis of preadipocytes through stimulate the phosphorylation of STAT1. Conclusions: Taken together, IA has been identified as a potent metabolite for the prevention or treatment of obesity. [ABSTRACT FROM AUTHOR]

Rhodococcus rhodochrous strain М8 is a platform for development of the biotechnologies for biocatalytic production of acrylic monomers, the raw material for synthesis of acrylic heteropolymers. A genetic system for investigation of the cobalt-dependent transcription of nitrile hydratase genes in this strain was constructed, based on the reporter gene of the metal-independent acylamidase from Rhodococcus qingshengii TA37. The cobalt-regulated promoter was shown to be located at a significant distance (~0.5 kb) from nitrile hydratase genes. Excision of the region between the promoter and the nitrile hydratase genes decreased significantly both the promoter activity and the degree of regulation by cobalt. Our results improve the possibilities for rational design of regulated expression cassettes using the promoter of nitrile hydratase genes in Rhodococcus, and for further development of biocatalysts based on these bacteria. [ABSTRACT FROM AUTHOR]

Comblike polycarboxylate superplasticizers (PCs) have been widely used as construction and building materials by means of high fluidity and fine dispersibility via electrostatic repulsion and steric hindrance. The conventional PCs are usually synthesized by free radical polymerization, which limit to understand and even distort the structure-property relationship due to the random molecular structure and the broad polydispersity. In this work, polycarboxylate ether superplasticizers of acrylic acid (AA) and ethylene glycol monovinyl PEG (EPEG) with controlled structure were prepared by reversible addition-fragmentation chain transfer (RAFT) polymerization. The resultant copolymers (denoted as EPCs) were characterized by FT-IR, 1H NMR and GPC spectroscopy. The effect of actual acid/ether (AA/EPEG) ratio on the adsorption capacity and dispersion ability of EPCs in cement paste were deeply investigated. These results demonstrate that the dispersibility of EPCs with controlled molecular weights and comparatively narrow polydispersity indexes (PDI=1.2–1.4) strongly depends on the acid/ether ratio. With an increase of the feed molar ratio of AA/EPEG from 4∶1 to 8∶1 , the molecular weight and their distribution of EPCs increases accordingly. In addition, the adsorption capacity and dispersion property of EPCs to cement are densely related to the molecular structure and composition and superior to that of conventional PC analogues. A possible mechanism was proposed that EPCs can act uniformly on the surface of cement particles due to the well-defined molecular structure and well-distributed molecular weight, which is different from the conventional PCs, which will offer the fundamentals of design and synthesis for polycarboxylate superplasticizers with controlled structures. [ABSTRACT FROM AUTHOR]

At present, controlling the workability of concrete with high clay content sand presents a significant engineering challenge. A novel phosphonate group-modified polycarboxylate superplasticizer (PHS-PCE) was synthesized by using 2-(methacryloyloxy) ethyl phosphate (MOEP), isobutyl alcohol polyoxyethylene ether (IPEG) and acrylic acid (AA). Gel permeation chromatography (GPC), Fourier-transform infrared spectroscopy (FT-IR), 31P nuclear magnetic resonance (31P NMR) spectroscopy and elemental analysis measurements were conducted to characterize the molecular structure of PHS-PCE showing successful incorporation of the phosphonate group with high polymer purity. Despite the relatively low reactivity of MOEP, approximately 65 wt% monomer was incorporated into the copolymer. PHS-PCE exhibited superior flowability and stronger retardation effect than the conventional polycarboxylate superplasticizer (C-PCE), due to the increased negative charge density and enhanced complexing capacity with calcium ion imparted by the phosphonate group. In the presence of clay, the maximum variation of PHS-PCE adsorption on cement particle was 18%, whereas that of C-PCE was 25%. The phosphonate group facilitates adsorption of a portion of PHS-PCE on the clay particle edges, thereby preventing intercalation and improving the clay tolerance. [ABSTRACT FROM AUTHOR]