High-energy density lithium-ion batteries(LIBs)with layered high-nickel oxide cathodes(LiNi_(x)Co_(y)Mn_(1-x-y)O_(2),x≥0.8)show great promise in consumer electronics and vehicular applications.However,LiNi_(x)Co_(y)M...High-energy density lithium-ion batteries(LIBs)with layered high-nickel oxide cathodes(LiNi_(x)Co_(y)Mn_(1-x-y)O_(2),x≥0.8)show great promise in consumer electronics and vehicular applications.However,LiNi_(x)Co_(y)Mn_(1-x-y)O_(2)faces challenges related to capacity decay caused by residual alkalis owing to high sensitivity to air.To address this issue,we propose a hazardous substances upcycling method that fundamentally mitigates alkali content and concurrently induces the emergence of an anti-air-sensitive layer on the cathode surface.Through the neutralization of polyacrylic acid(PAA)with residual alkalis and then coupling it with 3-aminopropyl triethoxysilane(KH550),a stable and ion-conductive cross-linked polymer layer is in situ integrated into the LiNi_(0.89)Co_(0.06)Mn_(0.05)O_(2)(NCM)cathode.Our characterization and measurements demonstrate its effectiveness.The NCM material exhibits impressive cycling performance,retaining 88.4%of its capacity after 200 cycles at 5 C and achieving an extraordinary specific capacity of 170.0 mA h g^(-1) at 10 C.Importantly,this layer on the NCM efficiently suppresses unfavorable phase transitions,severe electrolyte degradation,and CO_(2)gas evolution,while maintaining commendable resistance to air exposure.This surface modification strategy shows widespread potential for creating air-stable LiNi_(x)Co_(y)Mn_(1-x-y)O_(2)cathodes,thereby advancing high-performance LIBs.展开更多
Cross-linked pectin/high amylose mixtures were evaluated as a new excipient for matrix tablets formulations,since the mixing of polymers and cross-linking reaction represent rational tools to reach materials with modu...Cross-linked pectin/high amylose mixtures were evaluated as a new excipient for matrix tablets formulations,since the mixing of polymers and cross-linking reaction represent rational tools to reach materials with modulated and specific properties that meet specific therapeutic needs.Objective:In this work the influence of polymer ratio and cross-linking process on the swelling and the mechanism driving the drug release from swellable matrix tablets prepared with this excipient was investigated.Methods:Cross-linked samples were characterized by their micromeritic properties(size and shape,density,angle of repose and flow rate)and liquid uptake ability.Matrix tablets were evaluated according their physical properties and the drug release rates and mechanisms were also investigated.Results:Cross-linked samples demonstrated size homogeneity and irregular shape,with liquid uptake ability insensible to pH.Cross-linking process of samples allowed the control of drug release rates and the drug release mechanism was influenced by both polymer ratio and cross-linking process.The drug release of samples with minor proportion of pectin was driven by an anomalous transport and the increase of the pectin proportion contributed to the erosion of the matrix.Conclusion:The cross-linked mixtures of high amylose and pectin showed a suitable excipient for slowing the drug release rates.展开更多
Solid polymer electrolytes(SPEs)have become increasingly important in advanced lithium-ion batteries(LIBs)due to their improved safety and mechanical properties compared to organic liquid electrolytes.Cross-linked pol...Solid polymer electrolytes(SPEs)have become increasingly important in advanced lithium-ion batteries(LIBs)due to their improved safety and mechanical properties compared to organic liquid electrolytes.Cross-linked polymers have the potential to further improve the mechanical property without trading off Li-ion conductivity.In this study,focusing on a recently developed cross-linked SPE,i.e.,the one based on poly(vinylene carbonate)-poly(ethylene oxide)cross-linked network(PVCN),we used solid-state nuclear magnetic resonance(NMR)techniques to investigate the fundamental interaction between the chain segments and Li ions,as well as the lithium-ion motion.By utilizing homonuclear/heteronuclear correlation,CP(cross-polarization)kinetics,and spin-lattice relaxation experiments,etc.,we revealed the structural characteristics and their relations to lithium-ion mobilities.It is found that the network formation prevents poly(ethylene oxide)chains from crystallization,which could create sufficient space for segmental tumbling and Li-ion co nductio n.As such,the mechanical property is greatly improved with even higher Li-ion mobilities compared to the poly(vinylene carbonate)or poly(ethylene oxide)based SPE analogues.展开更多
Dimethyl carbonate(DMC)is a crucial chemical raw material widely used in organic synthesis,lithiumion battery electrolytes,and various other fields.The current primary industrial process employs a conventional sodium ...Dimethyl carbonate(DMC)is a crucial chemical raw material widely used in organic synthesis,lithiumion battery electrolytes,and various other fields.The current primary industrial process employs a conventional sodium methoxide basic catalyst to produce DMC through the transesterification reaction between vinyl carbonate and methanol.However,the utilization of this catalyst presents several challenges during the process,including equipment corrosion,the generation of solid waste,susceptibility to deactivation,and complexities in separation and recovery.To address these limitations,a series of alkaline poly(ionic liquid)s,i.e.[DVBPIL][PHO],[DVCPIL][PHO],and[TBVPIL][PHO],with different crosslinking degrees and structures,were synthesized through the construction of cross-linked polymeric monomers and functionalization.These poly(ionic liquid)s exhibit cross-linked structures and controllable cationic and anionic characteristics.Research was conducted to investigate the effect of the cross-linking degree and structure on the catalytic performance of transesterification in synthesizing DMC.It was discovered that the appropriate cross-linking degree and structure of the[DVCPIL][PHO]catalyst resulted in a DMC yield of up to 80.6%.Furthermore,this catalyst material exhibited good stability,maintaining its catalytic activity after repeated use five times without significant changes.The results of this study demonstrate the potential for using alkaline poly(ionic liquid)s as a highly efficient and sustainable alternative to traditional catalysts for the transesterification synthesis of DMC.展开更多
Thermosensitive hydrogel can integrate vapor molecular capture,in-situ liquefaction,and thermal-induced water release for freshwater capture.This study aimed to examine the dynamic behavior of poly(N-isopropylacrylami...Thermosensitive hydrogel can integrate vapor molecular capture,in-situ liquefaction,and thermal-induced water release for freshwater capture.This study aimed to examine the dynamic behavior of poly(N-isopropylacrylamide)(PNIPAM)single chain and cross-linking thermosensitive hydrogel through molecular dynamics simulation.Specifically,the impact of lower critical solution temperature(LCST)on the conformation of polymer chain and the interaction between water and polymer chain were also investigated.The polymer chain conformation underwent a transition from coil to globule when the temperature exceeded the LCST,indicating the temperature responsiveness of PNIPAM.Additionally,thermosensitive hydrogel samples with different cross-linking degrees(DOC)were studied,and relevant parameters such as the number of free water,the diffusion coefficient of water,and the pore size distribution were counted to evaluate the temperature responsiveness and water release characteristics of thermosensitive hydrogel.展开更多
The aim of this study was to modify the sago starch and evaluate its efficacy as tablet disintegrant. Cross-linked car-boxymethylated sago starch (CMSS) was synthesized using native sago starch (SS) and monochloroacet...The aim of this study was to modify the sago starch and evaluate its efficacy as tablet disintegrant. Cross-linked car-boxymethylated sago starch (CMSS) was synthesized using native sago starch (SS) and monochloroacetic acid (MCA) with sodium hydroxide in microwave radiation environment. FT-IR analysis of the sample confirmed the carboxy-methylation by showing absorption peak at 1607.2 cm-1. CMSS with degree of substitution (DS) of 0.31 was formed and, it was further evaluated as disintegrant in Ondasetron based tablets. The results revealed that CMSS could be used as disintegrant in tablet formulation in concentration dependant manner.展开更多
Starch biosynthesis is a complex process that relies on the coordinated action of multiple enzymes.Resistant starch is not digested in the small intestine,thus preventing a rapid rise in the glycemic index.Starch synt...Starch biosynthesis is a complex process that relies on the coordinated action of multiple enzymes.Resistant starch is not digested in the small intestine,thus preventing a rapid rise in the glycemic index.Starch synthase 2a(SS2a)is a key enzyme in amylopectin biosynthesis that has significant effects on starch structure and properties.In this study,we identified an ss2a null mutant(M3-1413)with a single base mutation from an ethyl methane sulfonate(EMS)-mutagenized population of barley.The mutation was located at the 3'end of the first intron of the RNA splicing receptor(AG)site,and resulted in abnormal RNA splicing and two abnormal transcripts of ss2a,which caused the inactivation of the SS2a gene.The starch structure and properties were significantly altered in the mutant,with M3-1413 containing lower total starch and higher amylose and resistant starch levels.This study sheds light on the effect of barley ss2a null mutations on starch properties and will help to guide new applications of barley starch in the development of nutritious food products.展开更多
Resistant starch(RS)has attracted much researchers'attention because of its health-beneficial effects.Gut microbiota obviously shapes human health,but the effects of RS supplementation on the changes of human gut ...Resistant starch(RS)has attracted much researchers'attention because of its health-beneficial effects.Gut microbiota obviously shapes human health,but the effects of RS supplementation on the changes of human gut microbiota remain unclear.This observational meta-analysis aimed to reveal the effects of RS intake onα-diversity and composition of gut microbiota through meta-analysis.Two independent authors systematically searched articles from inception until February 2023 on four electronic databases.Twenty-four highly relevant trials were included conforming to Preferred Reporting Items for Systematic reviews and MetaAnalysis protocol,and a total of 816 individuals were included.Significant heterogeneity analyses revealed that RS intake notably decreased Shannon index(weighted mean difference(WMD):-0.11;95%confidence interval(CI):-0.21,-0.01),and stimulated the composition of health promoting bacteria genera,including Bifidobacterium(relative abundance:WMD:1.75;95%CI:0.39,3.11;bacterial populations:WMD:0.36;95%CI:0.04,0.69),Faecalibacterium(relative abundance:WMD:0.70;95%CI:0.20,1.20;fold change:effect size:0.91;95%CI:0.60,1.23),and Prevotella(relative abundance:WMD:0.35;95%CI:0.01,0.69).Taken together,the present study revealed that changes in the gut microbiota diversity and genera were correlated with RS supplementation,which may contribute to benefits in human health.展开更多
Retrogradation of semi-dry rice noodles severely reduced their eating quality during storage.Three commonly used modified starches(oxidized starch,acetylated starch,and hydroxypropyl starch)were applied to investigate...Retrogradation of semi-dry rice noodles severely reduced their eating quality during storage.Three commonly used modified starches(oxidized starch,acetylated starch,and hydroxypropyl starch)were applied to investigate the anti-retrogradation effects of semi-dry rice noodles during cold storage.Loss of water content,migration of water,and increase in relative crystallinity,retrogradation enthalpy,and hardness could be retarded by adding chemically modified starches,especially hydroxypropyl starches.The effect of hydroxypropyl starch addition levels(2%,4%,6%,8%,and 10%)on the properties of rice flour and the edible quality of semi-dry rice noodles was further evaluated.The water solubility index of rice flour decreased with the addition of hydroxypropyl starch,while the swelling power showed the opposite trend.The quality of semi-dry rice noodles were improved with the addition of hydroxypropyl starch.Compared to the control,semi-dried rice noodles with 8%hydroxypropyl starch possessed superior properties,i.e.lower cooking loss(decreasing from 12.89%to 6.62%),lower adhesiveness(decreasing from 5.40 to 4.31 g·s),and higher hardness(rising from 10.89 to 13.81 N).These findings demonstrated that the incorporation of hydroxypropyl starch is a promising strategy for the preparation of semi-dry rice noodles with satisfactory cooking and edible qualities as well as a long shelf life.展开更多
5-Aminolevulinic acid(ALA)is a novel plant growth regulator that has shown outstanding capability to promote stomatal opening.Starch degradation,catalyzed byβ-amylase(EC3.2.1.2,BAM),plays an important role in stomata...5-Aminolevulinic acid(ALA)is a novel plant growth regulator that has shown outstanding capability to promote stomatal opening.Starch degradation,catalyzed byβ-amylase(EC3.2.1.2,BAM),plays an important role in stomatal opening.However,whether the starch breakdown is involved in ALA-regulating stomatal movement is unclear.In the current study,we found that exogenous ALA effectively stimulated the starch breakdown in guard cells,increasedβ-amylase activity and promoted stomatal opening in leaves of apple(Malus×domestica).Based on genome-wide identification,we identified a total of 119 members of BAM gene family in ten commonly Rosaceae crops.Analyses of gene structure,motif identification,and gene pair collinearity revealed relative conservation among members within the same group or subgroup.Among these genes,MdBAM17 and other 12 genes were identified as the orthologous genes of AtBAM1,which is responsible for starch degradation to modulate the stomatal movement in Arabidopsis.qRT-PCR analysis revealed a positive correlation between the expressions of MdBAM17 and stomatal aperture,as well asβ-amylase activity,whereas a negative correlation was observed with the starch content.Subcellular localization analysis confirmed that MdBAM17 is a chloroplast protein,consistent with the AtBAM1.MdBAM17 was mainly expressed in guard cells and responsive to exogenous ALA.Overexpressing MdBAM17 increasedβ-amylase activity and promoted starch breakdown,leading to stomatal opening,which was further strengthened by ALA.RNA-interfering MdBAM17 decreasedβ-amylase activity,resulting in starch accumulation,and impairing the stomatal opening by ALA.However,modulation of MdBAM17 expression did not affect the levels of flavonols and H_(2)O_(2)in guard cells,suggesting that MdBAM17-promoted starch degradation may function at downstream of ROS signaling in the ALAregulated stomatal opening.Our findings provide new insights into the mechanisms of ALA-regulated stomatal movement.展开更多
Banana fruit ripening is a highly regulatory process involving various layers consisting of transcriptional regulation,epigenetic factor,and post-translational modification.Previously,we reported that MaERF11 cooperat...Banana fruit ripening is a highly regulatory process involving various layers consisting of transcriptional regulation,epigenetic factor,and post-translational modification.Previously,we reported that MaERF11 cooperated with MaHDA1 to precisely regulate the transcription of ripening-associated genes via histone deacetylation.However,whether MaERF11 is subjected to post-translational modification during banana ripening is largely unknown.In this study,we found that MaERF11 targeted a subset of starch degradation-related genes using the DNA affinity purification sequence(DAP-Seq)approach.Electrophoretic mobility shift assay(EMSA)and dual-luciferase reporter assay(DLR)demonstrated that MaERF11 could specifically bind and repress the expression of the starch degradation-related genes MaAMY3,MaBAM2 and MaGWD1.Further analyses of yeast two-hybrid(Y2H),bimolecular fluorescence complementation(BiFC)and Luciferase complementation imaging(LCI)assays indicated that MaERF11 interacted with the ubiquitin E3 ligase MaRFA1,and this interaction weakened the MaERF11-mediated transcriptional repression capacity.Collectively,our results suggest an additional regulatory layer in which MaERF11 regulates banana fruit ripening and expands the regulatory network in fruit ripening at the post-translational modification level.展开更多
Selective hydrogenation of furfural to furfuryl alcohol is a great challenge in the hydrogenation field due to thermodynamic preference for hydrogenation of C=C over C=O.Herein,a novel Al_(2)O_(3)/C-u hybrid catalyst,...Selective hydrogenation of furfural to furfuryl alcohol is a great challenge in the hydrogenation field due to thermodynamic preference for hydrogenation of C=C over C=O.Herein,a novel Al_(2)O_(3)/C-u hybrid catalyst,composed of N-modified dendritic carbon networks supporting Al_(2)O_(3)nanoparticles,was successfully prepared via carbonizing the freeze-dried gel from spontaneous cross-linking of alginate,Al3+and urea.The obtained carbon-supported Al_(2)O_(3)hybrid catalyst has a high ratio (31%) of Al species in pentahedral-coordinated state.The introduction of urea enhances the surface N content,the ratio of pyrrolic N,and specific surface area of catalyst,leading to improved adsorption capacity of C=O and the accessibility of active sites.In the furfural hydrogenation reaction with isopropyl alcohol as hydrogen donor,Al_(2)O_(3)/C-u catalyst achieved a 90%conversion of furfural with 98.0% selectivity to furfuryl alcohol,outperforming that of commercial γ-Al_(2)O_(3).Moreover,Al_(2)O_(3)/C-u demonstrates excellent catalytic stability in the recycling tests attributed to the synergistic effect of abundant weak Lewis acid sites and the anchoring effect of the carbon network on Al_(2)O_(3)nanoparticles.This work provides an innovative and facile strategy for fabrication of carbon-supported Al_(2)O_(3)hybrid catalysts with rich AlVspecies,serving as a high selective hydrogenation catalyst through MPV reaction route.展开更多
Based on the ESI-MS and ^(13)C-NMR analysis of the forms of glyoxal in acidic and alkaline solutions,the soy-based adhesive cross-linked by glyoxal was prepared in this work.The results showed that glyoxal existed in ...Based on the ESI-MS and ^(13)C-NMR analysis of the forms of glyoxal in acidic and alkaline solutions,the soy-based adhesive cross-linked by glyoxal was prepared in this work.The results showed that glyoxal existed in water in different forms at different pH levels.Under alkaline conditions,glyoxal transformed to glycolate through the intramolecular disproportionation reaction.Under acidic conditions,although some of glyoxal transformed to glycolate as what happened under alkaline conditions,most of glyoxal molecules existed in the form of fiveor six-membered cyclic ether structure.No ethylene tetraol or free aldehyde group was actually detected under these conditions.Although glyoxal reacted with soy protein under both acidic and alkaline conditions,alkaline conditions were more favorable for the improvement of mechanical performance and water resistance of soybased adhesives than acid conditions.展开更多
The aim of this study is to analyze the various compositions of polyvinyl alcohol (PVA) and starch blends. The blends have been cross-linked with glyoxal to enhance its properties. The hydroxyl groups of PVA and starc...The aim of this study is to analyze the various compositions of polyvinyl alcohol (PVA) and starch blends. The blends have been cross-linked with glyoxal to enhance its properties. The hydroxyl groups of PVA and starch react with glyoxal via formation of acetal bonds;hence crosslinking could take place. The cross-linking of glyoxal is observed in various analytical methods such as DSC and FTIR. The cross-linked blends showed better thermal and mechanical properties. Viscosity, tensile shear strength, pencil hardness and ultimate stress were evaluated to estimate the changes due to cross-linking. It was observed that the cross-linking is directly proportional to starch, since the starch hydroxyl groups are easily accessible for reacting. The cross-linked blend showed better cohesion between its chains, thereby increasing glass transition temperature. It was reflected in the subsequent increase in tensile strength properties.展开更多
A new type of crown ether cross-linked chitosan was synthesized by the reaction of chitosan with 4,4′-dibromodibenzo-18-crown-6 (Br-DBC). Its token structure was analyzed with FT-IR and NMR and the adsorption behavio...A new type of crown ether cross-linked chitosan was synthesized by the reaction of chitosan with 4,4′-dibromodibenzo-18-crown-6 (Br-DBC). Its token structure was analyzed with FT-IR and NMR and the adsorption behaviors for lead and cadmium in environmental water samples by FAAS were studied. In addition the best analysis conditions were discussed and the adsorption mechanism was explained. As the enrichment factor is above 100, both recoveries are 94%–106%, the detection limits of lead and cadmium are 0.5μg·L?1 and 0.04 μg·L?1 and the relatively standard deviations of lead and cadmium are 3.1% and 2.8% respectively, this new method was successfully applied to the determination of environmental water samples. This method is fast and simple and it greatly enhances the determination ability of FAAS for lead and cadmium.展开更多
The performance of cross-linked magnetic chitosan, coated with magnetic fluids and cross-linked with ePichlorohydrin, was investigated for the adsorption of Copper (Ⅱ) from aqueous solutions. Infrared spectra of ch...The performance of cross-linked magnetic chitosan, coated with magnetic fluids and cross-linked with ePichlorohydrin, was investigated for the adsorption of Copper (Ⅱ) from aqueous solutions. Infrared spectra of chitosan before and after modification showed that the coating and cross-linking are effective. Experiments were performed at different pH of solution and contact time, and appropriate conditions for the adsorption of Cu(Ⅱ) were determined. Experimental equilibrium data were correlated with Langmuir and Freundlich isotherms for determination of the adsorption potential. The results showed that the Langmuir isotherm was better compared with the Freundlich isotherm, and the uptake of Cu(Ⅱ) was 78.13 mg·g^- 1. The kinetics of adsorption corresponded with the first-order Langergren rate equation, and Langergren rate constants were determined.展开更多
The grain surfaces(film surface and grain boundary)of polycrystalline perovskite films are vulnerable sites in solar cells since they pose a high defect density and initiate the degradation of perovskite absorber.Achi...The grain surfaces(film surface and grain boundary)of polycrystalline perovskite films are vulnerable sites in solar cells since they pose a high defect density and initiate the degradation of perovskite absorber.Achieving simultaneously defect passivation and grain protection from moisture is crucial for the viability of perovskite solar cells.Here,an in situ cross-linked grain encapsulation(CLGE)strategy that improves both device stability and defect passivation is reported.Cross-linkable semiconducting small molecules are mixed into the antisolvent to uniformly form a compact and conducting cross-linked layer over the grain surfaces.This cross-linked coating layer not only passivates trap states and facilitates hole extraction,but also enhances the device stability by preventing moisture diffusion.Using the CLGE strategy,a high power conversion efficiency(PCE)of 22.7%is obtained in 1.55-eV bandgap planar perovskite solar cells.The unencapsulated devices with CLGE exhibit significantly enhanced device stability again moisture and maintain>90%of their initial PCE after shelf storage under ambient condition for over10,000 h.展开更多
Large-scale and low-cost preparation of carbon-based potassium anode with long life and high capacity is one of the footstones for the development of potassium ion batteries(PIBs).Herein,a low-cost carbon-based materi...Large-scale and low-cost preparation of carbon-based potassium anode with long life and high capacity is one of the footstones for the development of potassium ion batteries(PIBs).Herein,a low-cost carbon-based material,cross-linked hollow graphitic carbon(HGC),is large scale synthesized to apply for PIBs anode.Its hollow structure can afford sufficient space to overcome the damage caused by the volume expansion of graphitic carbon(GC).While the cross-linked structure forms a compact interconnection network that allows electrons to rapid transfer between different GC frameworks.Electrochemical measurements demonstrated that the HGC anode exhibited low charge/discharge plateau(about 0.25 V and 0.1 V)and excellent specific capacity as high as 298 m A h g^(-1)at the current density of 50 m A g^(-1).And more important,after 200 cycles the capacity of HGC anode still shows 269 m A h g^(-1)(the decay rate of per cycle is only 0.048%).Meanwhile,the use of commercial traditional electrolyte(KPF_(6))and cheap raw materials that provide new hope for trying and realizing the large-scale production of PIBs based on carbon anode materials.展开更多
Performance characteristics of partially hydrolyzed polyacrylamide (HPAM) and cross- linked polymer (CLP, Cr^3+ as the cross linker) solutions have been investigated. A Brookfield viscometer, rheometer, dynamic l...Performance characteristics of partially hydrolyzed polyacrylamide (HPAM) and cross- linked polymer (CLP, Cr^3+ as the cross linker) solutions have been investigated. A Brookfield viscometer, rheometer, dynamic light scattering system, and core flow device have been used to measure the viscosity, viscoelasticity, polymer coil dimensions, molecular configuration, flow characteristics, and profile modification. The results show that, under conditions of high salinity and low HPAM and Cr^3+ concentrations, cross-linking mainly occurred between different chains of the same HPAM molecule in the presence of Cr^3+, and a cross-linked polymer (CLP) system with a local network structure was formed. Compared with an HPAM solution of the same concentration, the apparent viscosity of the CLP solution increased slightly or remained almost unchanged, but its viscoelasticity (namely storage modulus, loss modulus, and first normal stress difference) increased, and the resistance coefficient and residual resistance coefficient increased significantly. This indicates that the CLP solution exhibits a strong capability to divert the sequentially injected polymer flood from high-permeability zones to low- permeability zones in a reservoir. Under the same HPAM concentration conditions, the dimensions of polymer coils in the CLP solution increased slightly compared with the dimensions of polymer coils in HPAM solution, which were smaller than the rock pores, indicating that the cross-linked polymer solution was well adapted to reservoir rocks. Core flood experiments show that at the same cost of reagent, the oil recovery by CLP injection (HPAM-1, Cr^3+ as the cross linker) is 3.1% to 5.2% higher than that by HPAM- 2 injection.展开更多
基金supported by the National Natural Science Foundation of China(52162030)the Yunnan Major Scientific and Technological Projects(202202AG050003)+4 种基金the Key Research and Development Program of Yunnan Province(202103AA080019)the Scientific Research Foundation of Kunming University of Science and Technology(20220122)the Graduate Student Top Innovative Talent Program of Kunming University of Science and Technology(CA23107M139A)the Analysis and Testing Foundation of Kunming University of Science and Technology(2023T20220122)the Shenzhen Science and Technology Program(KCXST20221021111201003)。
文摘High-energy density lithium-ion batteries(LIBs)with layered high-nickel oxide cathodes(LiNi_(x)Co_(y)Mn_(1-x-y)O_(2),x≥0.8)show great promise in consumer electronics and vehicular applications.However,LiNi_(x)Co_(y)Mn_(1-x-y)O_(2)faces challenges related to capacity decay caused by residual alkalis owing to high sensitivity to air.To address this issue,we propose a hazardous substances upcycling method that fundamentally mitigates alkali content and concurrently induces the emergence of an anti-air-sensitive layer on the cathode surface.Through the neutralization of polyacrylic acid(PAA)with residual alkalis and then coupling it with 3-aminopropyl triethoxysilane(KH550),a stable and ion-conductive cross-linked polymer layer is in situ integrated into the LiNi_(0.89)Co_(0.06)Mn_(0.05)O_(2)(NCM)cathode.Our characterization and measurements demonstrate its effectiveness.The NCM material exhibits impressive cycling performance,retaining 88.4%of its capacity after 200 cycles at 5 C and achieving an extraordinary specific capacity of 170.0 mA h g^(-1) at 10 C.Importantly,this layer on the NCM efficiently suppresses unfavorable phase transitions,severe electrolyte degradation,and CO_(2)gas evolution,while maintaining commendable resistance to air exposure.This surface modification strategy shows widespread potential for creating air-stable LiNi_(x)Co_(y)Mn_(1-x-y)O_(2)cathodes,thereby advancing high-performance LIBs.
基金Coordenac¸a˜o de Aperfei-c¸oamento de Pessoal de Nı´vel Superior(CAPES)and Fundac¸a˜o de Amparo a`Pesquisa do Estado de Sa˜o Paulo(FAPESP)is acknowledged.F.M.C.thanks FAPESP for a M.Sci.scholarship.
文摘Cross-linked pectin/high amylose mixtures were evaluated as a new excipient for matrix tablets formulations,since the mixing of polymers and cross-linking reaction represent rational tools to reach materials with modulated and specific properties that meet specific therapeutic needs.Objective:In this work the influence of polymer ratio and cross-linking process on the swelling and the mechanism driving the drug release from swellable matrix tablets prepared with this excipient was investigated.Methods:Cross-linked samples were characterized by their micromeritic properties(size and shape,density,angle of repose and flow rate)and liquid uptake ability.Matrix tablets were evaluated according their physical properties and the drug release rates and mechanisms were also investigated.Results:Cross-linked samples demonstrated size homogeneity and irregular shape,with liquid uptake ability insensible to pH.Cross-linking process of samples allowed the control of drug release rates and the drug release mechanism was influenced by both polymer ratio and cross-linking process.The drug release of samples with minor proportion of pectin was driven by an anomalous transport and the increase of the pectin proportion contributed to the erosion of the matrix.Conclusion:The cross-linked mixtures of high amylose and pectin showed a suitable excipient for slowing the drug release rates.
基金financially supported by the National Natural Science Foundation of China(Grant No.22325405,22321002,22279153)Liaoning Revitalization Talents Program(XLYC1807207,XLYC2203134)DICP I202104。
文摘Solid polymer electrolytes(SPEs)have become increasingly important in advanced lithium-ion batteries(LIBs)due to their improved safety and mechanical properties compared to organic liquid electrolytes.Cross-linked polymers have the potential to further improve the mechanical property without trading off Li-ion conductivity.In this study,focusing on a recently developed cross-linked SPE,i.e.,the one based on poly(vinylene carbonate)-poly(ethylene oxide)cross-linked network(PVCN),we used solid-state nuclear magnetic resonance(NMR)techniques to investigate the fundamental interaction between the chain segments and Li ions,as well as the lithium-ion motion.By utilizing homonuclear/heteronuclear correlation,CP(cross-polarization)kinetics,and spin-lattice relaxation experiments,etc.,we revealed the structural characteristics and their relations to lithium-ion mobilities.It is found that the network formation prevents poly(ethylene oxide)chains from crystallization,which could create sufficient space for segmental tumbling and Li-ion co nductio n.As such,the mechanical property is greatly improved with even higher Li-ion mobilities compared to the poly(vinylene carbonate)or poly(ethylene oxide)based SPE analogues.
基金supported by the National Key Research and Development Program of China(2022YFB4101800)National Natural Science Foundation of China(22278077,22108040)+2 种基金Key Program of Qingyuan Innovation Laboratory(00221004)Research Program of Qingyuan Innovation Laboratory(00523006)Natural Science Foundation of Fujian Province(2022J02019)。
文摘Dimethyl carbonate(DMC)is a crucial chemical raw material widely used in organic synthesis,lithiumion battery electrolytes,and various other fields.The current primary industrial process employs a conventional sodium methoxide basic catalyst to produce DMC through the transesterification reaction between vinyl carbonate and methanol.However,the utilization of this catalyst presents several challenges during the process,including equipment corrosion,the generation of solid waste,susceptibility to deactivation,and complexities in separation and recovery.To address these limitations,a series of alkaline poly(ionic liquid)s,i.e.[DVBPIL][PHO],[DVCPIL][PHO],and[TBVPIL][PHO],with different crosslinking degrees and structures,were synthesized through the construction of cross-linked polymeric monomers and functionalization.These poly(ionic liquid)s exhibit cross-linked structures and controllable cationic and anionic characteristics.Research was conducted to investigate the effect of the cross-linking degree and structure on the catalytic performance of transesterification in synthesizing DMC.It was discovered that the appropriate cross-linking degree and structure of the[DVCPIL][PHO]catalyst resulted in a DMC yield of up to 80.6%.Furthermore,this catalyst material exhibited good stability,maintaining its catalytic activity after repeated use five times without significant changes.The results of this study demonstrate the potential for using alkaline poly(ionic liquid)s as a highly efficient and sustainable alternative to traditional catalysts for the transesterification synthesis of DMC.
基金supported by National Natural Science Foundation of China(No.52206073)Fundamental Research Funds for the Central Universities(No.3132023119)Guangdong Basic and Applied Basic Research Foundation(Nos.2024A1515011379 and 2023A1515110613).
文摘Thermosensitive hydrogel can integrate vapor molecular capture,in-situ liquefaction,and thermal-induced water release for freshwater capture.This study aimed to examine the dynamic behavior of poly(N-isopropylacrylamide)(PNIPAM)single chain and cross-linking thermosensitive hydrogel through molecular dynamics simulation.Specifically,the impact of lower critical solution temperature(LCST)on the conformation of polymer chain and the interaction between water and polymer chain were also investigated.The polymer chain conformation underwent a transition from coil to globule when the temperature exceeded the LCST,indicating the temperature responsiveness of PNIPAM.Additionally,thermosensitive hydrogel samples with different cross-linking degrees(DOC)were studied,and relevant parameters such as the number of free water,the diffusion coefficient of water,and the pore size distribution were counted to evaluate the temperature responsiveness and water release characteristics of thermosensitive hydrogel.
文摘The aim of this study was to modify the sago starch and evaluate its efficacy as tablet disintegrant. Cross-linked car-boxymethylated sago starch (CMSS) was synthesized using native sago starch (SS) and monochloroacetic acid (MCA) with sodium hydroxide in microwave radiation environment. FT-IR analysis of the sample confirmed the carboxy-methylation by showing absorption peak at 1607.2 cm-1. CMSS with degree of substitution (DS) of 0.31 was formed and, it was further evaluated as disintegrant in Ondasetron based tablets. The results revealed that CMSS could be used as disintegrant in tablet formulation in concentration dependant manner.
基金supported by the Major Program of National Agricultural Science and Technology of China(NK20220607)the Sichuan Science and Technology Program,China(2023YFH0041)。
文摘Starch biosynthesis is a complex process that relies on the coordinated action of multiple enzymes.Resistant starch is not digested in the small intestine,thus preventing a rapid rise in the glycemic index.Starch synthase 2a(SS2a)is a key enzyme in amylopectin biosynthesis that has significant effects on starch structure and properties.In this study,we identified an ss2a null mutant(M3-1413)with a single base mutation from an ethyl methane sulfonate(EMS)-mutagenized population of barley.The mutation was located at the 3'end of the first intron of the RNA splicing receptor(AG)site,and resulted in abnormal RNA splicing and two abnormal transcripts of ss2a,which caused the inactivation of the SS2a gene.The starch structure and properties were significantly altered in the mutant,with M3-1413 containing lower total starch and higher amylose and resistant starch levels.This study sheds light on the effect of barley ss2a null mutations on starch properties and will help to guide new applications of barley starch in the development of nutritious food products.
基金financially supported by the National Key R&D Program of China(2022YFF1100600,2022YFF1100605)the Science and Technology Support Program(Modern Agriculture)of Jiangsu Province(BE2022323)the National Natural Science Foundation of China(32302011)。
文摘Resistant starch(RS)has attracted much researchers'attention because of its health-beneficial effects.Gut microbiota obviously shapes human health,but the effects of RS supplementation on the changes of human gut microbiota remain unclear.This observational meta-analysis aimed to reveal the effects of RS intake onα-diversity and composition of gut microbiota through meta-analysis.Two independent authors systematically searched articles from inception until February 2023 on four electronic databases.Twenty-four highly relevant trials were included conforming to Preferred Reporting Items for Systematic reviews and MetaAnalysis protocol,and a total of 816 individuals were included.Significant heterogeneity analyses revealed that RS intake notably decreased Shannon index(weighted mean difference(WMD):-0.11;95%confidence interval(CI):-0.21,-0.01),and stimulated the composition of health promoting bacteria genera,including Bifidobacterium(relative abundance:WMD:1.75;95%CI:0.39,3.11;bacterial populations:WMD:0.36;95%CI:0.04,0.69),Faecalibacterium(relative abundance:WMD:0.70;95%CI:0.20,1.20;fold change:effect size:0.91;95%CI:0.60,1.23),and Prevotella(relative abundance:WMD:0.35;95%CI:0.01,0.69).Taken together,the present study revealed that changes in the gut microbiota diversity and genera were correlated with RS supplementation,which may contribute to benefits in human health.
基金funded by the fund of national natural science foundation of China(32101996,32160530)the training plan for academic and technical leaders of major disciplines in Jiangxi province(20232BCJ23024)+1 种基金the key research and development program of Jiangxi province(20232BBF60023)“Shuangqian Project”of Jiangxi Province(jxsq2023201042)。
文摘Retrogradation of semi-dry rice noodles severely reduced their eating quality during storage.Three commonly used modified starches(oxidized starch,acetylated starch,and hydroxypropyl starch)were applied to investigate the anti-retrogradation effects of semi-dry rice noodles during cold storage.Loss of water content,migration of water,and increase in relative crystallinity,retrogradation enthalpy,and hardness could be retarded by adding chemically modified starches,especially hydroxypropyl starches.The effect of hydroxypropyl starch addition levels(2%,4%,6%,8%,and 10%)on the properties of rice flour and the edible quality of semi-dry rice noodles was further evaluated.The water solubility index of rice flour decreased with the addition of hydroxypropyl starch,while the swelling power showed the opposite trend.The quality of semi-dry rice noodles were improved with the addition of hydroxypropyl starch.Compared to the control,semi-dried rice noodles with 8%hydroxypropyl starch possessed superior properties,i.e.lower cooking loss(decreasing from 12.89%to 6.62%),lower adhesiveness(decreasing from 5.40 to 4.31 g·s),and higher hardness(rising from 10.89 to 13.81 N).These findings demonstrated that the incorporation of hydroxypropyl starch is a promising strategy for the preparation of semi-dry rice noodles with satisfactory cooking and edible qualities as well as a long shelf life.
基金supported by the Natural Science Foundation of China(Grant No.32172512)the Jiangsu Special Fund for Frontier Foundation Research of Carbon Peaking and Carbon Neutralization(Grant No.BK20220005)a project funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions。
文摘5-Aminolevulinic acid(ALA)is a novel plant growth regulator that has shown outstanding capability to promote stomatal opening.Starch degradation,catalyzed byβ-amylase(EC3.2.1.2,BAM),plays an important role in stomatal opening.However,whether the starch breakdown is involved in ALA-regulating stomatal movement is unclear.In the current study,we found that exogenous ALA effectively stimulated the starch breakdown in guard cells,increasedβ-amylase activity and promoted stomatal opening in leaves of apple(Malus×domestica).Based on genome-wide identification,we identified a total of 119 members of BAM gene family in ten commonly Rosaceae crops.Analyses of gene structure,motif identification,and gene pair collinearity revealed relative conservation among members within the same group or subgroup.Among these genes,MdBAM17 and other 12 genes were identified as the orthologous genes of AtBAM1,which is responsible for starch degradation to modulate the stomatal movement in Arabidopsis.qRT-PCR analysis revealed a positive correlation between the expressions of MdBAM17 and stomatal aperture,as well asβ-amylase activity,whereas a negative correlation was observed with the starch content.Subcellular localization analysis confirmed that MdBAM17 is a chloroplast protein,consistent with the AtBAM1.MdBAM17 was mainly expressed in guard cells and responsive to exogenous ALA.Overexpressing MdBAM17 increasedβ-amylase activity and promoted starch breakdown,leading to stomatal opening,which was further strengthened by ALA.RNA-interfering MdBAM17 decreasedβ-amylase activity,resulting in starch accumulation,and impairing the stomatal opening by ALA.However,modulation of MdBAM17 expression did not affect the levels of flavonols and H_(2)O_(2)in guard cells,suggesting that MdBAM17-promoted starch degradation may function at downstream of ROS signaling in the ALAregulated stomatal opening.Our findings provide new insights into the mechanisms of ALA-regulated stomatal movement.
基金financially supported by the National Natural Science Foundation of China(Grant Nos.31830071,32202561)the earmarked fund for CARS(Grant No.CARS-31)。
文摘Banana fruit ripening is a highly regulatory process involving various layers consisting of transcriptional regulation,epigenetic factor,and post-translational modification.Previously,we reported that MaERF11 cooperated with MaHDA1 to precisely regulate the transcription of ripening-associated genes via histone deacetylation.However,whether MaERF11 is subjected to post-translational modification during banana ripening is largely unknown.In this study,we found that MaERF11 targeted a subset of starch degradation-related genes using the DNA affinity purification sequence(DAP-Seq)approach.Electrophoretic mobility shift assay(EMSA)and dual-luciferase reporter assay(DLR)demonstrated that MaERF11 could specifically bind and repress the expression of the starch degradation-related genes MaAMY3,MaBAM2 and MaGWD1.Further analyses of yeast two-hybrid(Y2H),bimolecular fluorescence complementation(BiFC)and Luciferase complementation imaging(LCI)assays indicated that MaERF11 interacted with the ubiquitin E3 ligase MaRFA1,and this interaction weakened the MaERF11-mediated transcriptional repression capacity.Collectively,our results suggest an additional regulatory layer in which MaERF11 regulates banana fruit ripening and expands the regulatory network in fruit ripening at the post-translational modification level.
基金China Postdoctoral Science Foundation (2023M733451)Dalian Innovation Team in Key Areas(2020RT06)Engineering Research Center for Key Aromatic Compounds and LiaoNing Key Laboratory,Liaoning Provincial Natural Science Foundation (Doctoral Research Start-up Fund 2024-BSBA-37)。
文摘Selective hydrogenation of furfural to furfuryl alcohol is a great challenge in the hydrogenation field due to thermodynamic preference for hydrogenation of C=C over C=O.Herein,a novel Al_(2)O_(3)/C-u hybrid catalyst,composed of N-modified dendritic carbon networks supporting Al_(2)O_(3)nanoparticles,was successfully prepared via carbonizing the freeze-dried gel from spontaneous cross-linking of alginate,Al3+and urea.The obtained carbon-supported Al_(2)O_(3)hybrid catalyst has a high ratio (31%) of Al species in pentahedral-coordinated state.The introduction of urea enhances the surface N content,the ratio of pyrrolic N,and specific surface area of catalyst,leading to improved adsorption capacity of C=O and the accessibility of active sites.In the furfural hydrogenation reaction with isopropyl alcohol as hydrogen donor,Al_(2)O_(3)/C-u catalyst achieved a 90%conversion of furfural with 98.0% selectivity to furfuryl alcohol,outperforming that of commercial γ-Al_(2)O_(3).Moreover,Al_(2)O_(3)/C-u demonstrates excellent catalytic stability in the recycling tests attributed to the synergistic effect of abundant weak Lewis acid sites and the anchoring effect of the carbon network on Al_(2)O_(3)nanoparticles.This work provides an innovative and facile strategy for fabrication of carbon-supported Al_(2)O_(3)hybrid catalysts with rich AlVspecies,serving as a high selective hydrogenation catalyst through MPV reaction route.
基金This work was supported by Science-technology Support Foundation of Guizhou Province of China(Nos.[2019]2325 and [2020]1Y125)the Growth Project of Young Scientific and Technological Talents in Colleges and Universities of Guizhou Province(No.[2019]184)+1 种基金Yunnan Fundamental Research Key Projects(No.2019FA012)National Natural Science Foundation of China(Nos.31870546 and 31800481).
文摘Based on the ESI-MS and ^(13)C-NMR analysis of the forms of glyoxal in acidic and alkaline solutions,the soy-based adhesive cross-linked by glyoxal was prepared in this work.The results showed that glyoxal existed in water in different forms at different pH levels.Under alkaline conditions,glyoxal transformed to glycolate through the intramolecular disproportionation reaction.Under acidic conditions,although some of glyoxal transformed to glycolate as what happened under alkaline conditions,most of glyoxal molecules existed in the form of fiveor six-membered cyclic ether structure.No ethylene tetraol or free aldehyde group was actually detected under these conditions.Although glyoxal reacted with soy protein under both acidic and alkaline conditions,alkaline conditions were more favorable for the improvement of mechanical performance and water resistance of soybased adhesives than acid conditions.
文摘The aim of this study is to analyze the various compositions of polyvinyl alcohol (PVA) and starch blends. The blends have been cross-linked with glyoxal to enhance its properties. The hydroxyl groups of PVA and starch react with glyoxal via formation of acetal bonds;hence crosslinking could take place. The cross-linking of glyoxal is observed in various analytical methods such as DSC and FTIR. The cross-linked blends showed better thermal and mechanical properties. Viscosity, tensile shear strength, pencil hardness and ultimate stress were evaluated to estimate the changes due to cross-linking. It was observed that the cross-linking is directly proportional to starch, since the starch hydroxyl groups are easily accessible for reacting. The cross-linked blend showed better cohesion between its chains, thereby increasing glass transition temperature. It was reflected in the subsequent increase in tensile strength properties.
文摘A new type of crown ether cross-linked chitosan was synthesized by the reaction of chitosan with 4,4′-dibromodibenzo-18-crown-6 (Br-DBC). Its token structure was analyzed with FT-IR and NMR and the adsorption behaviors for lead and cadmium in environmental water samples by FAAS were studied. In addition the best analysis conditions were discussed and the adsorption mechanism was explained. As the enrichment factor is above 100, both recoveries are 94%–106%, the detection limits of lead and cadmium are 0.5μg·L?1 and 0.04 μg·L?1 and the relatively standard deviations of lead and cadmium are 3.1% and 2.8% respectively, this new method was successfully applied to the determination of environmental water samples. This method is fast and simple and it greatly enhances the determination ability of FAAS for lead and cadmium.
文摘The performance of cross-linked magnetic chitosan, coated with magnetic fluids and cross-linked with ePichlorohydrin, was investigated for the adsorption of Copper (Ⅱ) from aqueous solutions. Infrared spectra of chitosan before and after modification showed that the coating and cross-linking are effective. Experiments were performed at different pH of solution and contact time, and appropriate conditions for the adsorption of Cu(Ⅱ) were determined. Experimental equilibrium data were correlated with Langmuir and Freundlich isotherms for determination of the adsorption potential. The results showed that the Langmuir isotherm was better compared with the Freundlich isotherm, and the uptake of Cu(Ⅱ) was 78.13 mg·g^- 1. The kinetics of adsorption corresponded with the first-order Langergren rate equation, and Langergren rate constants were determined.
基金financially supported by the National Key R&D Program of China(2018YFB1500102,2018YFB2200101)the National Natural Science Foundation of China(61974063,61921005)+3 种基金Natural Science Foundation of Jiangsu Province(BK20190315)the Fundamental Research Funds for the Central Universities(14380168)the Thousand Talent Program for Young Outstanding Scientists in ChinaProgram for Innovative Talents and Entrepreneur in Jiangsu。
文摘The grain surfaces(film surface and grain boundary)of polycrystalline perovskite films are vulnerable sites in solar cells since they pose a high defect density and initiate the degradation of perovskite absorber.Achieving simultaneously defect passivation and grain protection from moisture is crucial for the viability of perovskite solar cells.Here,an in situ cross-linked grain encapsulation(CLGE)strategy that improves both device stability and defect passivation is reported.Cross-linkable semiconducting small molecules are mixed into the antisolvent to uniformly form a compact and conducting cross-linked layer over the grain surfaces.This cross-linked coating layer not only passivates trap states and facilitates hole extraction,but also enhances the device stability by preventing moisture diffusion.Using the CLGE strategy,a high power conversion efficiency(PCE)of 22.7%is obtained in 1.55-eV bandgap planar perovskite solar cells.The unencapsulated devices with CLGE exhibit significantly enhanced device stability again moisture and maintain>90%of their initial PCE after shelf storage under ambient condition for over10,000 h.
基金financially supported by National Natural Science Foundation of China(Nos.51922038 and 51672078)Hunan Outstanding Youth Talents(No.2019JJ20005)
文摘Large-scale and low-cost preparation of carbon-based potassium anode with long life and high capacity is one of the footstones for the development of potassium ion batteries(PIBs).Herein,a low-cost carbon-based material,cross-linked hollow graphitic carbon(HGC),is large scale synthesized to apply for PIBs anode.Its hollow structure can afford sufficient space to overcome the damage caused by the volume expansion of graphitic carbon(GC).While the cross-linked structure forms a compact interconnection network that allows electrons to rapid transfer between different GC frameworks.Electrochemical measurements demonstrated that the HGC anode exhibited low charge/discharge plateau(about 0.25 V and 0.1 V)and excellent specific capacity as high as 298 m A h g^(-1)at the current density of 50 m A g^(-1).And more important,after 200 cycles the capacity of HGC anode still shows 269 m A h g^(-1)(the decay rate of per cycle is only 0.048%).Meanwhile,the use of commercial traditional electrolyte(KPF_(6))and cheap raw materials that provide new hope for trying and realizing the large-scale production of PIBs based on carbon anode materials.
基金financial support from the National Key Technology R&D Program in the 12th Five Year Plan of PetroChina (No: 2011ZX05010-003-02)the National Key Technology R&D Program in the 12th Five Year Plan of CNOOC (No: 2011ZX05024-04-05-03)
文摘Performance characteristics of partially hydrolyzed polyacrylamide (HPAM) and cross- linked polymer (CLP, Cr^3+ as the cross linker) solutions have been investigated. A Brookfield viscometer, rheometer, dynamic light scattering system, and core flow device have been used to measure the viscosity, viscoelasticity, polymer coil dimensions, molecular configuration, flow characteristics, and profile modification. The results show that, under conditions of high salinity and low HPAM and Cr^3+ concentrations, cross-linking mainly occurred between different chains of the same HPAM molecule in the presence of Cr^3+, and a cross-linked polymer (CLP) system with a local network structure was formed. Compared with an HPAM solution of the same concentration, the apparent viscosity of the CLP solution increased slightly or remained almost unchanged, but its viscoelasticity (namely storage modulus, loss modulus, and first normal stress difference) increased, and the resistance coefficient and residual resistance coefficient increased significantly. This indicates that the CLP solution exhibits a strong capability to divert the sequentially injected polymer flood from high-permeability zones to low- permeability zones in a reservoir. Under the same HPAM concentration conditions, the dimensions of polymer coils in the CLP solution increased slightly compared with the dimensions of polymer coils in HPAM solution, which were smaller than the rock pores, indicating that the cross-linked polymer solution was well adapted to reservoir rocks. Core flood experiments show that at the same cost of reagent, the oil recovery by CLP injection (HPAM-1, Cr^3+ as the cross linker) is 3.1% to 5.2% higher than that by HPAM- 2 injection.