Objective: to improve the production efficiency and recovery of xylo-oligosaccharide by optimizing the adsorption and hydrolysis conditions of corn cob solid residue by fusion enzyme. Xylose oligosaccharide was prepar...Objective: to improve the production efficiency and recovery of xylo-oligosaccharide by optimizing the adsorption and hydrolysis conditions of corn cob solid residue by fusion enzyme. Xylose oligosaccharide was prepared by catalytic coupling adsorption enzyme. Results the optimal adsorption conditions were substrate concentration 5%, pH 7.0, temperature 20℃ and adsorption time 30min. Under the optimal conditions, the adsorption rate of dissolved protein was 90.3%. The optimum enzymolysis conditions were ph7.0, temperature 50℃ and reaction time 24h. The yield of xylitol was 47.7% and the average degree of polymerization was 2.3. TLC analysis showed that xylitol, iron xylose, tetraxylose and amyl ester sugar were contained in the enzymolysis products. The quantitative results of HPLC showed that the contents of xylitol and xylanase were 45.2% and 36.7%, respectively. Conclusion: this study will not only provide a basis for the new technology of adsorption-catalytic coupling to produce xylo-oligosaccharides, but also provide a reference for other preparation methods of oligosaccharides.展开更多
A series of CeO_(2)@MnO_(2)composites was prepared by deposition-precipitation methods.These materials were used to activate sodium persulfate(PDS)for the oxidation of tetracycline.It is found that the composites,espe...A series of CeO_(2)@MnO_(2)composites was prepared by deposition-precipitation methods.These materials were used to activate sodium persulfate(PDS)for the oxidation of tetracycline.It is found that the composites,especially the CeO_(2)@MnO_(2)-1:4 composites,exhibit better tetracycline removal rates than the pure components.X-ray diffraction(XRD),Raman and scanning electron microscopy(SEM)analyses all indicate that the composite has been successfully prepared with high purity and high crystalline.The XPS analysis shows that the strong interaction between the components promotes the electron transfer.Additionally,the kinetic rate constants of CeO_(2)@MnO_(2)-1:4 after 60 min are 3.8 and 12.7 times higher than pure CeO_(2)and MnO_(2),respectively.CeO_(2)@MnO_(2-)1:4 composite also exhibits excellent catalytic activity for individual and hybrid pollutants.The effects of wastewater matrix,pH,circulation and ion stre ngth on the degradation of tetracycline were investigated.It is found that CeO_(2)@MnO_(2)-1:4 composite has good practical application prospects.CeO_(2)@MnO_(2)composites with synergistic adsorption catalysis can activate PDS and peroxymo no sulfate(PMS)for efficient organic catalytic oxidation.This paper provides the theoretical basis and data support for the practical application of the CeO_(2)@MnO_(2)composite materials.展开更多
Room-temperature sodium–sulfur(RT Na–S)batteries are highly competitive energy storage devices due to their abundant natural reserves,low cost,and excellent theoretical energy density.S cathode,as an important compo...Room-temperature sodium–sulfur(RT Na–S)batteries are highly competitive energy storage devices due to their abundant natural reserves,low cost,and excellent theoretical energy density.S cathode,as an important component of RT Na–S,has challenges during charging/discharging processes,including large fluctuations in the volume of the S species during sodiation/desodiation,severe shuttle effect,and sluggish reaction kinetics,which greatly limit the development and practical application of RT Na–S.To solve these problems,the researchers designed a variety of reactors with different morphologies to inhibit the shuttling of sodium polysulfides(NaPSs)through van der Waals forces and mitigate the volume change during charging/discharging processes.It was found that the addition of suitable catalyst materials could increase the ion/electron transport rate of S cathode and improve the electrochemical performance through adsorption-catalysis synergy.Herein,a comprehensive review is conducted for the improvement work of RT Na–S battery cathode in the last decade,including reactor design,catalyst design,and S cathode design.Finally,the major challenges facing the development of cathode materials for RT Na–S batteries are summarized,and their future directions are outlined.展开更多
文摘Objective: to improve the production efficiency and recovery of xylo-oligosaccharide by optimizing the adsorption and hydrolysis conditions of corn cob solid residue by fusion enzyme. Xylose oligosaccharide was prepared by catalytic coupling adsorption enzyme. Results the optimal adsorption conditions were substrate concentration 5%, pH 7.0, temperature 20℃ and adsorption time 30min. Under the optimal conditions, the adsorption rate of dissolved protein was 90.3%. The optimum enzymolysis conditions were ph7.0, temperature 50℃ and reaction time 24h. The yield of xylitol was 47.7% and the average degree of polymerization was 2.3. TLC analysis showed that xylitol, iron xylose, tetraxylose and amyl ester sugar were contained in the enzymolysis products. The quantitative results of HPLC showed that the contents of xylitol and xylanase were 45.2% and 36.7%, respectively. Conclusion: this study will not only provide a basis for the new technology of adsorption-catalytic coupling to produce xylo-oligosaccharides, but also provide a reference for other preparation methods of oligosaccharides.
基金Project supported by the Science and Technology Project of Henan Province(242102321048,242102321045,232102320211)National Natural Science Foundation of China(22206080)+2 种基金Natural Science Foundation of Jiangsu(SBK2022041070)International Science and Technology Cooperation Projects of Henan Province(232102521009)Natural Science Youth Foundation of Henan Province(232300420336)。
文摘A series of CeO_(2)@MnO_(2)composites was prepared by deposition-precipitation methods.These materials were used to activate sodium persulfate(PDS)for the oxidation of tetracycline.It is found that the composites,especially the CeO_(2)@MnO_(2)-1:4 composites,exhibit better tetracycline removal rates than the pure components.X-ray diffraction(XRD),Raman and scanning electron microscopy(SEM)analyses all indicate that the composite has been successfully prepared with high purity and high crystalline.The XPS analysis shows that the strong interaction between the components promotes the electron transfer.Additionally,the kinetic rate constants of CeO_(2)@MnO_(2)-1:4 after 60 min are 3.8 and 12.7 times higher than pure CeO_(2)and MnO_(2),respectively.CeO_(2)@MnO_(2-)1:4 composite also exhibits excellent catalytic activity for individual and hybrid pollutants.The effects of wastewater matrix,pH,circulation and ion stre ngth on the degradation of tetracycline were investigated.It is found that CeO_(2)@MnO_(2)-1:4 composite has good practical application prospects.CeO_(2)@MnO_(2)composites with synergistic adsorption catalysis can activate PDS and peroxymo no sulfate(PMS)for efficient organic catalytic oxidation.This paper provides the theoretical basis and data support for the practical application of the CeO_(2)@MnO_(2)composite materials.
基金financially supported by the National Natural Science Foundation of China(No.U21A2077)the Natural Science Foundation of Shandong Province(Nos.ZR2022JQ08 and ZR2024MB003)+1 种基金the Taishan Scholar Project Foundation of Shandong Province(No.tsqn202211028)the China Postdoctoral Science Foundation(Nos.2023TQ0192 and 2023M742065).
文摘Room-temperature sodium–sulfur(RT Na–S)batteries are highly competitive energy storage devices due to their abundant natural reserves,low cost,and excellent theoretical energy density.S cathode,as an important component of RT Na–S,has challenges during charging/discharging processes,including large fluctuations in the volume of the S species during sodiation/desodiation,severe shuttle effect,and sluggish reaction kinetics,which greatly limit the development and practical application of RT Na–S.To solve these problems,the researchers designed a variety of reactors with different morphologies to inhibit the shuttling of sodium polysulfides(NaPSs)through van der Waals forces and mitigate the volume change during charging/discharging processes.It was found that the addition of suitable catalyst materials could increase the ion/electron transport rate of S cathode and improve the electrochemical performance through adsorption-catalysis synergy.Herein,a comprehensive review is conducted for the improvement work of RT Na–S battery cathode in the last decade,including reactor design,catalyst design,and S cathode design.Finally,the major challenges facing the development of cathode materials for RT Na–S batteries are summarized,and their future directions are outlined.
