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Dispersive Ability of Carboxylated Cellulose Nanofibrils for Aqueous Monolayer Montmorillonite Dispersion:Influence of Na^(+) and Ca^(2+) Concentrations

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Paper And Biomaterials 2022年第1期7卷 28-37页

作者： kaihuang chen Chuan Sun Guanhui Li Jinhao Huang Zhiqiang Fang Xueqing Qiu School of Chemistry and Chemical Engineering South China University of TechnologyGuangzhouGuangdong Province510640China State Key Laboratory of Pulp and Paper Engineering South China University of TechnologyGuangzhouGuangdong Province510640China School of Chemical Engineering and Light Industry Guangdong Provincial Key Laboratory of Plant Resources BiorefineryGuangdong University of TechnologyGuangzhouGuangdong Province510006China

Carboxylated cellulose nanofibrils(CNFs)have emerged as effective green dispersants for monolayer montmorillonite(MMT)***,their dispersion capability is sensitive to the metal ion concentration in aqueous ***,this study investigated the effects of Na^(+) and Ca^(2+) concentrations on the dispersive ability of carboxylated CNFs for monolayer MMTs in *** crystal microbalance with dissipation monitoring(QCM-D)and atomic force microscopy(AFM)were utilized to explore the interfacial interactions between the carboxylated CNFs and monolayer MMTs under different Na^(+) and Ca^(2+) *** the concentration of Na^(+) reached 0.1 mmol/L,the adhesion mass of carboxylated CNFs on MMT-coated wafer peaked at 24.47 mg/m^(2),higher than control sample(carboxylated CNF-dispersed monolayer MMT dispersion without metal ions,16.03 mg/m^(2)).Moreover,the electrostatic shielding effect promoted a better dispersion of monolayer MMTs by carboxylated CNF *** a further increase in the Na^(+) concentration,the surface charge of CNFs and MMTs would be reversed resulting from the improved electrostatic shielding effect,which weaken the dispersive ability of carboxylated *** addition of Ca^(2+) reduced the dispersive ability of carboxylated CNFs for monolayer MMTs,because Ca^(2+) required a lower concentration for the onset of charge reversal compared to Na^(+).This study provides interfacial scale insights into the influence of metal ion concentration on carboxylated CNF-dispersed monolayer MMT *** also provides a strategy to enhance the dispersive ability of carboxylated CNFs for monolayer MMTs.

关键词： monolayer montmorillonite carboxylated cellulose nanofibrils dispersion mechanism metal ion

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滇黔桂盆地碎屑物源的变化及其对古特提斯洋演化历史的启示

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山东国土资源 2021年第3期37卷 11-21页

作者：陈开煌皮桥辉桂林理工大学地球科学学院广西桂林541004

古特提斯洋的构造与演化过程一直是研究热点,很多学者在其产生、扩张、俯冲及闭合的时间上持有不同观点。本次研究中,运用LA-ICP-MS锆石U-Pb测年技术对滇黔桂盆地三叠纪罗楼组碎屑锆石、泥盆纪坡松冲组碎屑独居石进行分析测试,同时结合... 详细信息

古特提斯洋的构造与演化过程一直是研究热点,很多学者在其产生、扩张、俯冲及闭合的时间上持有不同观点。本次研究中,运用LA-ICP-MS锆石U-Pb测年技术对滇黔桂盆地三叠纪罗楼组碎屑锆石、泥盆纪坡松冲组碎屑独居石进行分析测试,同时结合古生代以来碎屑物源的演化历史,以期确定出古特提斯洋开启与闭合的时间。锆石测试结果显示:者桑地区罗楼组碎屑锆石U-Pb年龄主要集中在308-396 Ma,440-680 Ma,727-930 Ma,1004-1266 Ma,1400-1880 Ma,2360-2724 Ma;老寨湾地区坡松冲组碎屑独居石U-Pb年龄则主要集中在657-460 Ma和998-798 Ma。通过对比研究区与周围地块的年龄分布特征,联系研究区岩相古地理、古海流以及古流向等地质证据,发现滇黔桂盆地古生代时期碎屑物源在460 Ma左右发生了变化,460 Ma以前碎屑物源主要来自印度北部、喜马拉雅、拉萨、羌塘、海南岛、澳大利亚西部及江南造山带,460 Ma以后碎屑物源主要来自越北古陆、湘粤桂构造山系,云开地区也可能提供了碎屑物源。

关键词：古特提斯洋碎屑物源锆石U-Pb定年独居石U-Pb定年滇黔桂盆地

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纳米纤维素/纳米铜复合材料制备及应用研究进展

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中国造纸 2021年第10期40卷 88-99页

作者：熊梓航方志强杨东杰周杰陈开湟邱学青华南理工大学化学与化工学院广东广州510641 华南理工大学制浆造纸工程国家重点实验室广东广州510641 广东工业大学轻工化工学院广东广州510006

纳米纤维素/纳米铜复合材料兼顾了纳米纤维素的优异力学和光学性能、高比表面积、低热膨胀系数、环境友好等特性以及铜的导电、导热、抗菌等性能,近年来在锂离子电池、多相催化、抗菌领域有广泛的应用。本文首先分别介绍了纳米纤维素和... 详细信息

纳米纤维素/纳米铜复合材料兼顾了纳米纤维素的优异力学和光学性能、高比表面积、低热膨胀系数、环境友好等特性以及铜的导电、导热、抗菌等性能,近年来在锂离子电池、多相催化、抗菌领域有广泛的应用。本文首先分别介绍了纳米纤维素和纳米铜的制备方法和理化特性;重点阐述了纳米纤维素/纳米铜复合材料的制备方法(物理沉积法和化学还原法)、理化特性(导电性能、催化性能和抗菌性能)及其在电子器件、催化剂和抗菌材料的应用进展;最后总结了纳米纤维素/纳米铜复合材料存在的问题并展望了未来的发展趋势。

关键词：纳米复合材料纳米铜纳米纤维素

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Halogen composition and heterogeneity in the continental lithospheric mantle

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Science China Earth Sciences 2025年第1期68卷 310-314页

作者： Chunfei chen State Key Laboratory of Geological Processes and Mineral Resources School of Earth Sciences China University of Geosciences

1. Introduction Halogens, including fluorine(F), chlorine(Cl), bromine(Br), and iodine(I), are highly mobile and water-soluble elements that can become significantly enriched in melts and fluids. In fluids and melts, halogens react with nearly all metals and readily form complexes with metal cations, significantly influencing the distribution of metal elements between different phases. Therefore, halogens play a crucial role in the migration, enrichment, and mineralization of key metals in the lithosphere(Weis et al., 2012; Liu et al., 2024).

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Cyano migration-mediated radical-polar crossover cyclopropanation

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Science China Chemistry 2025年第1期68卷 241-248页

作者： Ziqiang Wang Yasu chen Jie Li chen Zhu Key Laboratory of Organic Synthesis of Jiangsu Province College of Chemistry Chemical Engineering and Materials ScienceSoochow University Frontiers Science Center for Transformative Molecules Zhangjiang Institute for Advanced Study and Shanghai Key Laboratory for Molecular Engineering of Chiral Drugs Shanghai Jiao Tong University

We report a novel cyano migration-mediated radical-polar crossover process, whereby both the sulfonylcyanation of aliphatic alkenes and the formation of cyclopropanes are concurrently achieved. This transformation yields a diverse array of multisubstituted cyclopropanes under mild photocatalytic conditions. Mechanistic studies elucidate that the reaction proceeds via intramolecular nucleophilic substitution, leading to the formation of the cyclopropane derivatives.

关键词： cyclopropanation cyano migration radical-polar crossover radical reactions

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Two paths, one goal: mechanism of calcium homeostasis to balance plant growth and immunity

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Science China Life Sciences 2025年第1期68卷 306-308页

作者： Aziz Ul Ikram Yanping Jing Huan chen Jian chen International Genome Center Jiangsu University Joint Center for Single Cell Biology School of Agriculture and BiologyShanghai Jiao Tong University

Calcium(Ca2+) is an essential nutrient and a cellular signal in plants. The level of free Ca2+in the apoplast is ～10,000-fold higher than that in the cytoplasm at the resting state. This large Ca2+level gradient across the membrane between the interior and exterior can cause Ca2+overload and toxicity. Plants have evolved mechanisms to export Ca2+out of the cytoplasm or store it in intracellular organelles, such as endoplasmic reticulum（ER）, mitochondria, and vacuole.

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Efficient photocatalytic reduction of CO2 to formate by a molecular noble metal-free system

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Science China Chemistry 2025年第1期68卷 152-156页

作者： Lihua Zhang Lingjing chen Huatian Shi Yue Wei Gui chen Tai-Chu Lau School of Environment and Civil Engineering Research Center for Eco-environmental Engineering Dongguan University of Technology Department of Chemistry and Institute of Molecular Functional Materials City University of Hong Kong

Reducing CO2to carbon-neutral solar fuels can not only alleviate the energy demand but also mitigate the greenhouse *** present,developing an efficient non-noble metal photo/electrocatalytic system for converting CO2to a specific product beyond CO is still a big ***,we report a new cobalt complex bearing 2,2′-bi-1,10-phenanthroline ligand that can photocatalytically reduce CO2to formate （HCOO-）.Turnover number （TON） for HCOO-up to 677 with 99%selectivity can be achieved using organic dyes purpurin as photosensitizer and 1,3-dimethyl-2-phenyl-2,3-dihydro-1H-benzo[d]imidazole （BIH） as sacrificial reductant in a CO2-saturated NMP/TEA （v/v,3:1） solution under visible light *** potential electrolysis at-1.41 V （***/Ag Cl） in the presence of 12 m M Et3NHBF4also produced HCOO-with Faradaic efficiency of 39%.Spectroscopic and electrochemical studies suggest that a[CoI-H]species is the key intermediate for CO2reduction.

关键词： photocatalysis noble metal-free CO2 reduction formate cobalt hydride

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Toward understanding the role of genomic repeat elements in neurodegenerative diseases

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Neural Regeneration Research 2025年第3期20卷 646-659页

作者： Zhengyu An Aidi Jiang Jingqi chen Institute of Science and Technology for Brain-Inspired Intelligence Fudan UniversityShanghaiChina MOE Frontiers Center for Brain Science Fudan UniversityShanghaiChina MOE Key Laboratory of Computational Neuroscience and Brain-Inspired Intelligence Fudan UniversityShanghaiChina Zhangjiang Fudan International Innovation Center ShanghaiChina

Neurodegenerative diseases cause great medical and economic burdens for both patients and society;however, the complex molecular mechanisms thereof are not yet well understood. With the development of high-coverage sequencing technology, researchers have started to notice that genomic repeat regions, previously neglected in search of disease culprits, are active contributors to multiple neurodegenerative diseases. In this review, we describe the association between repeat element variants and multiple degenerative diseases through genome-wide association studies and targeted sequencing. We discuss the identification of disease-relevant repeat element variants, further powered by the advancement of long-read sequencing technologies and their related tools, and summarize recent findings in the molecular mechanisms of repeat element variants in brain degeneration, such as those causing transcriptional silencing or RNA-mediated gain of toxic function. Furthermore, we describe how in silico predictions using innovative computational models, such as deep learning language models, could enhance and accelerate our understanding of the functional impact of repeat element variants. Finally, we discuss future directions to advance current findings for a better understanding of neurodegenerative diseases and the clinical applications of genomic repeat elements.

关键词： Alzheimer's disease ataxia deep learning long-read sequencing neurodegeneration neurodegenerative diseases Parkinson's disease repeat element structural variant

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Fabrication and Mechano-sensing Characteristics of Bending Polypyrrole Actuator

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 240-245页

作者： chen Jinyou HU Wei School of Automotive Engineering Hunan Financial&Industrial Vocational-technical CollegeHengyang 421002China College of Mechanical and Electrical Engineering Hunan Agricultural UniversityChangsha 410128China

To prepare a conductive polymer actuator with decent performance,a self-built experimental platform for the preparation of polypyrrole film is *** of the essential goals is to examine the mechanical characteristics of the actuator in the presence of various combinations of process parameters,combined with the orthogonal test method of"four factors and three levels".The bending and sensing characteristics of actuators of various sizes are methodically examined using a self-made bending polypyrrole *** functional relationship between the bending displacement and the output voltage signal is established by studying the characteristics of the actuator sensor subjected to various degrees of *** experimental results reveal that the bending displacement of the actuator tip almost exhibits a linear variation as a function of length and *** the voltage reaches 0.8 V,the bending speed of the actuator tends to be ***,the mechanical properties of the self-assembled polypyrrole actuator are verified by the design and fabrication of the microgripper.

关键词： conductive polymer polypyrrole mechanical characteristics actuators sensing characteristics

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Miyaoka-type inequalities for terminal threefolds with nef anti-canonical divisors

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Science China Mathematics 2025年第1期68卷 1-18页

作者： Masataka Iwai chen Jiang Haidong Liu Department of Mathematics Graduate School of ScienceOsaka University Shanghai Center for Mathematical Sciences & School of Mathematical Sciences Fudan University Department of mathematics Sun Yat-sen University

In this paper,we study Miyaoka-type inequalities on Chern classes of terminal projective 3-folds with nef anti-canonical *** X be a terminal projective 3-fold such that-KXis *** show that if c1（X） · c2（X）≠0,then c1（X） · c2（X） ≥ 1/252;if further X is not rationally connected,then c1（X） · c2（X） ≥ 4/5 and this inequality is *** order to prove this,we give a partial classification of such varieties along with many *** also study the nonvanishing of c1（X）dim X-2· c2（X） for terminal weak Fano varieties and prove a Miyaoka-Kawamata-type inequality.

关键词： terminal threefolds Miyaoka-type inequality boundedness

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