Furthermore, all hydrogels exhibited salt sensitivity and excellent water retention capacity under the high temperature state and displayed smart swelling behaviors in physiological saline solutions. The water absorbency, reusability, and salt sensitivity of the hydrogels give these smart polymer wide promising applications.In this study, nickel-catalyzed electrochemical oxidative esterification of thiols with alcohols for the synthesis of sulfinate esters has been reported. The electrochemical oxidative esterification proceeded through a nickel-catalyzed oxidation of thiols using an undivided cell of graphite/nickel electrodes, where the nickel oxidation was studied by cyclic voltammetry. The method was conveniently and directly used for the one-pot synthesis of sulfinate esters of thiols.In water remediation, biomimetic membranes are gaining **** attention due to their selectivity, dynamic stability, nontoxicity, and biocompatibility. Lyotropic liquid crystals (LLCs) are self-organizing networks that can conform to an array of geometries with high pore densities. As such, LLCs are excellent membrane materials for water applications because they are water insoluble and are manipulated to conform to an array of morphologies that provide natural water channels that are readily tunable in size. They have the ability to create uniform pores, between the range of 1 and 5 nm, with large surface areas. Thus, this work focuses on the design, fabrication, and characterization of LLC-modified Janus-type membranes for forward osmosis applications. Physical characterization of the membranes was performed using scanning electron microscopy (SEM), and the results show an open-pore radius and the presence of both finger- and sponge-like pores depending on membrane preparation. The contact angle assessment indicates that as the membranes are further modified with other polymers (e.g., PAN), higher hydrophilicity and surface energy are achieved. Moreover, the Brunauer-Emmett-Teller (BET) analysis showed a significant variation in the pore distribution between membranes. Functionalized membranes presented satisfactory water flux and superior salt rejection compared to nonfunctionalized membranes. SupPACMoDS membranes are 83% more efficient at preventing salt **** flux than the nonmodified version. This is credited to the thickness and pore structure provided by the PAN support layer in the membrane.Based on the implementation of the global Minamata Convention, developing an efficient and economical technology for mercury reduction in coal-fired flue gas becomes a hotspot in the field of air pollution control. The composite oxidant NaClO/NaClO2 combined with limestone was used in the simultaneous removal of SO2 and Hg0 in this study, and the three-factor and four-level orthogonal experiments were performed in a packed tower. The influential sequence of various factors on SO2 and Hg0 removals was investigated through range analysis of the orthogonal experiments. https://www.selleckchem.com/products/triapine.html Results showed that factors affecting desulfurization was C > A > B (liquid-gas ratio > oxidant concentration ratio > initial pH of absorption liquid), while factors affecting Hg0 removal was A > C > B (oxidant concentration ratio > liquid-gas ratio > initial pH of absorption liquid). Optimum conditions of simultaneous desulfurization and demercuration by NaClO/NaClO2 were A4B1C4; that is, the oxidant concentration ratio was 10/4 (mmol/Lmmol/L), the initial pH was 5, and the liquid-gas ratio was 18 (L/m3). The simultaneous removal efficiencies of SO2 and Hg0 reached 99.5 and 85.4% under these optimum conditions, respectively. Analysis of the characteristics of the solid products showed that the main products of the wet oxidation were CaSO4 and CaSO3. Analysis of the existing form of oxidized mercury showed that 23% of mercury was in the gypsum, while 77% was in the supernatant. Results of this research would provide a practical reference for promoting the simultaneous removal of SO2 and Hg0 by NaClO/NaClO2 with limestone in industrial application.Pure gases and mixtures containing stable isotopes are used in a wide variety of applications including health care, food authentication, geochemistry, and environmental monitoring. It is therefore important to understand the role of moisture, which is one of the most critical impurities in compressed gas mixtures and pure gases, in their stability. Gaseous carbon dioxide (CO2) was used as a proxy for the evaluation of the effects of its isotopic composition, when in contact with moisture throughout the depletion of a cylinder's contents, as well as pressure regulation and long-term stability. To accentuate the detrimental effects of moisture on CO2 isotopic stability, enriched 18O-water was added to natural-abundance, gaseous carbon dioxide. The δ18O-CO2 changed from -23.16‰ vs Vienna Pee Dee Belemnite (VPDB) to +109‰ vs VPDB. It was further demonstrated that with appropriate cylinder preparation to reduce residual moisture, source material purity with low moisture content, and pressure regulation (from 57.0 down to 0.5 bar), both δ13C and δ18O remained consistent within ±0.04 and ±0.06‰, respectively, throughout the entire cylinder contents. Pressure reduction using a dual-stage regulator yielded statistically consistent results at the 99% confidence level from delivered pressures of 0.1-0.8 bar. Furthermore, the isotopic values remained consistent during a 1 year shelf-life study, illustrating the ability to utilize and regulate pressurized gases as working reference standard gases.In order to assist the refolding of recombinant nitrilase inclusion bodies, a series of thermoresponsive media were prepared by grafting poly(N-isopropylacrylamide-co-butyl-methacrylate) [P(NIPAM-co-BMA)] brushes onto PS microspheres with various particles and pore sizes via an atom transfer radical polymerization (ATRP) method. The effects of particle sizes, pore sizes, and brush grafting amounts of thermoresponsive microspheres on nitrilase refolding were investigated preliminarily. The results showed that the PS-P(NIPAM-co-BMA) microspheres with the medium particle size (74 μm), gigapore size (320 nm), and high grafting amount (35.6 mg/m2) were the most effective candidates. The final nitrilase activity yield could be up to 84.5% with a high initial protein concentration (1 mg/mL) at 30 °C, which was 52.5% higher than that of a simple dilution refolding method at the initial protein concentration (0.1 mg/mL). After the refolding process, the PS-P(NIPAM-co-BMA) microspheres can be easily separated by self-precipitation, and the activity yield of nitrilase still reached 74.
Furthermore, all hydrogels exhibited salt sensitivity and excellent water retention capacity under the high temperature state and displayed smart swelling behaviors in physiological saline solutions. The water absorbency, reusability, and salt sensitivity of the hydrogels give these smart polymer wide promising applications.In this study, nickel-catalyzed electrochemical oxidative esterification of thiols with alcohols for the synthesis of sulfinate esters has been reported. The electrochemical oxidative esterification proceeded through a nickel-catalyzed oxidation of thiols using an undivided cell of graphite/nickel electrodes, where the nickel oxidation was studied by cyclic voltammetry. The method was conveniently and directly used for the one-pot synthesis of sulfinate esters of thiols.In water remediation, biomimetic membranes are gaining much attention due to their selectivity, dynamic stability, nontoxicity, and biocompatibility. Lyotropic liquid crystals (LLCs) are self-organizing networks that can conform to an array of geometries with high pore densities. As such, LLCs are excellent membrane materials for water applications because they are water insoluble and are manipulated to conform to an array of morphologies that provide natural water channels that are readily tunable in size. They have the ability to create uniform pores, between the range of 1 and 5 nm, with large surface areas. Thus, this work focuses on the design, fabrication, and characterization of LLC-modified Janus-type membranes for forward osmosis applications. Physical characterization of the membranes was performed using scanning electron microscopy (SEM), and the results show an open-pore radius and the presence of both finger- and sponge-like pores depending on membrane preparation. The contact angle assessment indicates that as the membranes are further modified with other polymers (e.g., PAN), higher hydrophilicity and surface energy are achieved. Moreover, the Brunauer-Emmett-Teller (BET) analysis showed a significant variation in the pore distribution between membranes. Functionalized membranes presented satisfactory water flux and superior salt rejection compared to nonfunctionalized membranes. SupPACMoDS membranes are 83% more efficient at preventing salt back flux than the nonmodified version. This is credited to the thickness and pore structure provided by the PAN support layer in the membrane.Based on the implementation of the global Minamata Convention, developing an efficient and economical technology for mercury reduction in coal-fired flue gas becomes a hotspot in the field of air pollution control. The composite oxidant NaClO/NaClO2 combined with limestone was used in the simultaneous removal of SO2 and Hg0 in this study, and the three-factor and four-level orthogonal experiments were performed in a packed tower. The influential sequence of various factors on SO2 and Hg0 removals was investigated through range analysis of the orthogonal experiments. https://www.selleckchem.com/products/triapine.html Results showed that factors affecting desulfurization was C > A > B (liquid-gas ratio > oxidant concentration ratio > initial pH of absorption liquid), while factors affecting Hg0 removal was A > C > B (oxidant concentration ratio > liquid-gas ratio > initial pH of absorption liquid). Optimum conditions of simultaneous desulfurization and demercuration by NaClO/NaClO2 were A4B1C4; that is, the oxidant concentration ratio was 10/4 (mmol/Lmmol/L), the initial pH was 5, and the liquid-gas ratio was 18 (L/m3). The simultaneous removal efficiencies of SO2 and Hg0 reached 99.5 and 85.4% under these optimum conditions, respectively. Analysis of the characteristics of the solid products showed that the main products of the wet oxidation were CaSO4 and CaSO3. Analysis of the existing form of oxidized mercury showed that 23% of mercury was in the gypsum, while 77% was in the supernatant. Results of this research would provide a practical reference for promoting the simultaneous removal of SO2 and Hg0 by NaClO/NaClO2 with limestone in industrial application.Pure gases and mixtures containing stable isotopes are used in a wide variety of applications including health care, food authentication, geochemistry, and environmental monitoring. It is therefore important to understand the role of moisture, which is one of the most critical impurities in compressed gas mixtures and pure gases, in their stability. Gaseous carbon dioxide (CO2) was used as a proxy for the evaluation of the effects of its isotopic composition, when in contact with moisture throughout the depletion of a cylinder's contents, as well as pressure regulation and long-term stability. To accentuate the detrimental effects of moisture on CO2 isotopic stability, enriched 18O-water was added to natural-abundance, gaseous carbon dioxide. The δ18O-CO2 changed from -23.16‰ vs Vienna Pee Dee Belemnite (VPDB) to +109‰ vs VPDB. It was further demonstrated that with appropriate cylinder preparation to reduce residual moisture, source material purity with low moisture content, and pressure regulation (from 57.0 down to 0.5 bar), both δ13C and δ18O remained consistent within ±0.04 and ±0.06‰, respectively, throughout the entire cylinder contents. Pressure reduction using a dual-stage regulator yielded statistically consistent results at the 99% confidence level from delivered pressures of 0.1-0.8 bar. Furthermore, the isotopic values remained consistent during a 1 year shelf-life study, illustrating the ability to utilize and regulate pressurized gases as working reference standard gases.In order to assist the refolding of recombinant nitrilase inclusion bodies, a series of thermoresponsive media were prepared by grafting poly(N-isopropylacrylamide-co-butyl-methacrylate) [P(NIPAM-co-BMA)] brushes onto PS microspheres with various particles and pore sizes via an atom transfer radical polymerization (ATRP) method. The effects of particle sizes, pore sizes, and brush grafting amounts of thermoresponsive microspheres on nitrilase refolding were investigated preliminarily. The results showed that the PS-P(NIPAM-co-BMA) microspheres with the medium particle size (74 μm), gigapore size (320 nm), and high grafting amount (35.6 mg/m2) were the most effective candidates. The final nitrilase activity yield could be up to 84.5% with a high initial protein concentration (1 mg/mL) at 30 °C, which was 52.5% higher than that of a simple dilution refolding method at the initial protein concentration (0.1 mg/mL). After the refolding process, the PS-P(NIPAM-co-BMA) microspheres can be easily separated by self-precipitation, and the activity yield of nitrilase still reached 74.
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