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Residual alkali-evoked cross-linked polymer layer for anti-air-sensitivity LiNi_(0.89)Co_(0.06)Mn_(0.05)O_(2)cathode 被引量:1
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作者 Chao Zhao Xuebao Li +7 位作者 Yun Zhao Jingjing He Yuanpeng Cao Wei Luo Ding Wang Jianguo Duan Xianshu Wang Baohua Li 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第5期450-458,共9页
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
关键词 Lithium-ion batteries Nickel-rich layered cathode Residual alkalis cross-linked polyme rmodification Airsensitivity
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Insights into the swelling process and drug release mechanisms from cross-linked pectin/high amylose starch matrices 被引量:1
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作者 Fernanda M.Carbinatto Ana Do´ris de Castro +1 位作者 Raul C.Evangelista Beatriz S.F.Cury 《Asian Journal of Pharmaceutical Sciences》 SCIE CAS 2014年第1期27-34,共8页
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
关键词 High amylose starch PECTIN cross-linking SWELLING Drug delivery mechanism
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Mechanism of high Li-ion conductivity in poly(vinylene carbonate)-poly(ethylene oxide)cross-linked network based electrolyte revealed by solid-state NMR
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作者 Fan Li Tiantian Dong +5 位作者 Yi Ji Lixin Liang Kuizhi Chen Huanrui Zhang Guanglei Cui Guangjin Hou 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第6期377-383,I0010,共8页
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
关键词 ssNMR Lithium-ion mobility cross-link Solid polymer electrolyte
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Tuning the cross-linked structure of basic poly(ionic liquid)to develop an efficient catalyst for the conversion of vinyl carbonate to dimethyl carbonate
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作者 Zhaoyang Qi Shiquan Zhong +4 位作者 Huiyun Su Changshen Ye Limei Ren Ting Qiu Jie Chen 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第8期106-116,共11页
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
关键词 Poly(ionic liquid) cross-linking degree Dimethyl carbonate production Transesterification reaction Mechanism
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Molecular Dynamics Study on Hydrothermal Response of PNIPAM:From Single Chain to Cross-Linked Polymer
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作者 Xianzhi Chen Dong Niu +1 位作者 Hongtao Gao Mu Du 《Frontiers in Heat and Mass Transfer》 EI 2024年第6期1743-1760,共18页
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
关键词 Thermosensitive hydrogel water harvesting coil to globule cross-linked molecular dynamics simulation
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Microwave Assisted Synthesis and Evaluation of Cross-Linked Carboxymethylated Sago Starch as Superdisintegrant
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作者 Akhilesh V. Singh Lila K. Nath +1 位作者 Manisha Guha Rakesh Kumar 《Pharmacology & Pharmacy》 2011年第1期42-46,共5页
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
关键词 SAGO starch CARBOXYMETHYLATION DISINTEGRANT SEM FT-IR
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A barley SS2a single base mutation at the splicing site leads to obvious changes in starch
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作者 Bang Wang Jing Liu +12 位作者 Xiaolei Chen Qiang Xu Yazhou Zhang Huixue Dong Huaping Tang Pengfei Qi Mei Deng Jian Ma Jirui Wang Guoyue Chen Yuming Wei Youliang Zheng Qiantao Jiang 《Journal of Integrative Agriculture》 2025年第4期1359-1371,共13页
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
关键词 BARLEY EMS mutagenesis starch synthase 2a splicing site mutation starch property resistant starch
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Effect of resistant starch supplementation on the diversity and composition of human gut microbiota:a systematic review and meta-analysis
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作者 Jiaxin Xu Haocun Kong +2 位作者 Caiming Li Xiaofeng Ban Zhaofeng Li 《Food Science and Human Wellness》 2025年第3期850-863,共14页
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
关键词 Resistant starch Gut microbiota META-ANALYSIS HUMAN
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Effect of chemically modified starch on retrogradation and quality characteristics of semi-dry rice noodles
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作者 Xudong Yan Weirong Wen +3 位作者 Meng Li Shunjing Luo Jiangping Ye Chengmei Liu 《Grain & Oil Science and Technology》 2025年第1期13-20,共8页
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
关键词 Semi-dry noodles Modified starch RETROGRADATION Edible quality
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MdBAM17, a novel member of the β-amylase gene family,positively regulates starch degradation in ALA-induced stomatal opening in apple
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作者 Longbo Liu Jiayi Zhou +2 位作者 Jianting Zhang Yan Zhong Liangju Wang 《Horticultural Plant Journal》 2025年第2期504-519,共16页
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
关键词 ALA APPLE BAM gene family MdBAM17 starch degradation Stomatal opening
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Interaction of MaERF11 with the E3 ubiquitin ligase MaRFA1 is involved in the regulation of banana starch degradation during postharvest ripening
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作者 Mengge Jiang Yingying Yang +6 位作者 Wei Wei Chaojie Wu Wei Shan Jianfei Kuang Jianye Chen Shouxing Wei Wangjin Lu 《Horticultural Plant Journal》 2025年第2期608-618,共11页
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
关键词 BANANA MaERF11 E3 ubiquitin ligase MaRFA1 Fruit ripening starch degradation
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Fabrication of carbon-supported Al_(2)O_(3) nanoparticles via spontaneous cross-linking to enhance selective hydrogenation of furfural
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作者 Weiwei Yu Xinbao Zhang +6 位作者 Hongyu Chen Yanan Wang Shaoguo Li Fucun Chen Zhenni Liu Xiujie Li Xiangxue Zhu 《Journal of Energy Chemistry》 2025年第1期612-620,共9页
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
关键词 Selective hydrogenation FURFURAL Furfuryl alcohol cross-linking Carbon supported Al_(2)O_(3) MPV route
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Carboxymethyl starch cross-linked by electron beam radiation in presence of acrylic acid sensitizer
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作者 Doan Binh Nguyen Thanh Duoc Pham Thi Thu Hong 《Nuclear Science and Techniques》 SCIE CAS CSCD 2013年第B12期19-22,共4页
关键词 交联密度 羧甲基淀粉 电子束辐射 丙烯酸 敏化剂 FT-IR光谱 吸收剂量 CMS
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Study on the Soy Protein-Based Adhesive Cross-Linked by Glyoxal 被引量:6
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作者 Zhigang Wu Jiankun Liang +3 位作者 Hong Lei Bengang Zhang Xuedong Xi Lifen Li 《Journal of Renewable Materials》 SCIE EI 2021年第2期205-218,共14页
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
关键词 GLYOXAL soy protein-based adhesive cross-link
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Study on Various Compositions of Polyvinyl Alcohol and Starch Blends by Cross-Linking with Glyoxal 被引量:3
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作者 Ravindra V. Gadhave Prakash A. Mahanwar Pradeep T. Gadekar 《Open Journal of Polymer Chemistry》 2019年第4期76-85,共10页
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
关键词 starch Polyvinyl ALCOHOL cross-linking GLYOXAL Mechanical Testing
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Applications of Crown Ether Cross-Linked Chitosan for the Analysis of Lead and Cadmium in Environmental Water Samples 被引量:6
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作者 Tang Yu-rong Zhang Shu-qin +1 位作者 Wang Yu-ting Feng Xue-song 《Wuhan University Journal of Natural Sciences》 CAS 2002年第2期217-221,共5页
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
关键词 Crown ether cross-linked chitosan lead and cadmium ADSORPTION FAAS
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Adsorptive Removal of Copper Ions from Aqueous Solution Using Cross-linked Magnetic Chitosan Beads 被引量:13
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作者 黄国林 杨婥 +1 位作者 章凯 SHI Jeffrey 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2009年第6期960-966,共7页
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
关键词 adsorption of copper (Ⅱ) cross-linked magnetic chitosan Langmuir isotherm Langergren rate equation
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Simultaneously enhanced moisture tolerance and defect passivation of perovskite solar cells with cross-linked grain encapsulation 被引量:3
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作者 Ke Xiao Qiaolei Han +6 位作者 Yuan Gao Shuai Gu Xin Luo Renxing Lin Jia Zhu Jun Xu Hairen Tan 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2021年第5期455-462,共8页
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
关键词 Perovskite solar cell cross-link Defect passivation Stability Moisture tolerance
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Cross-Linked Hollow Graphitic Carbon as Low-Cost and High-Performance Anode for Potassium Ion Batteries 被引量:5
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作者 Yanhong Feng Suhua Chen +2 位作者 Dongyang Shen Jiang Zhou Bingan Lu 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2021年第3期451-457,共7页
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
关键词 cross-linked hollow structure graphitic material high reversibility potassium ion battery
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Study of action mechanisms and properties of Cr^(3+) cross-linked polymer solution with high salinity 被引量:8
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作者 Lu Xiangguo Liu Jinxiang +2 位作者 Wang Rongjian Liu Yigang Zhang Song 《Petroleum Science》 SCIE CAS CSCD 2012年第1期75-81,共7页
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
关键词 cross-linked polymer solution apparent viscosity VISCOELASTICITY polymer coil dimension molecular configuration flow characteristics profile modification
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