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Chinese Chemical Letters 2023年第9期34卷 138-142页

作者： Bao-Gui cai Guo-Yong Xu Jun xuan Anhui Province Key Laboratory of Chemistry for Inorganic/Organic Hybrid Functionalized Materials College of Chemistry&Chemical EngineeringAnhui UniversityHefei 230601China Key Laboratory of Structure and Functional Regulation of Hybrid Materials Ministry of EducationHefei 230601China Institute of Physical Science and Information Technology Anhui UniversityHefei 230601China

Herein,we report an efficient photochemical method for the synthesis of poly-substituted pyrazoles through a multicomponent reaction of acceptor-only diazoalkanes,alkynes,and solvents(cyclic ethers or nitriles).The key to this success was driven by the photolysis of acceptor-only diazoalkanes to form free carbene species and the fast in situ[3+2]-cycloaddition formation of nucleophilic N–H pyrazole *** work also serves as an entry to allow future reaction design on the combination of carbene reactivity of diazoalkanes with their other reaction modes.

关键词： Photochemical synthesis Multicomponent reaction Diazoalkanes Carbene Pyrazoles

Asymptotic Speed of Wave Propagation for A Discrete Reaction-Diffusion Equation

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Acta Mathematicae Applicatae Sinica 2006年第3期22卷 369-386页

作者： Xiu-xiang Liu pei-xuan Weng School of Mathematics Science South China Normal University Guangzhou 510631 China

We deal with asymptotic speed of wave propagation for a discrete reactlon-diffusion equation. We find the minimal wave speed c★ from the characteristic equation and show that c★ is just the asymptotic speed of wave propagation. The isotropic property and the existence of solution of the initial value problem for the given equation are also discussed.

关键词： Discrete reaction-diffusion equation travelling wave solutions monotone iteration asymptotic speed of wave propagation isotropic property

Macroscopic Regulation of Hierarchical Nanostructures in Liquid-crystalline Block Copolymers towards Functional Materials

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Chinese Journal of Polymer Science 2021年第4期39卷 397-416,I0004页

作者： Feng cai Yu-xuan Chen Wen-Zhong Wang Hai-Feng Yu Department of Materials Science and Engineering and Key Laboratory of Polymer Chemistry and Physics of Ministry of EducationCollege of EngineeringPeking UniversityBeijing 100871China

The great potential of liquid-crystalline block copolymers(LCBCs)containing photoresponsive mesogens toward novel applications in photonics and nanotechnology has been attracting increasing attention,due to the combination of the inherent property of microphase separation of block copolymers and the hierarchically-assembled structures of liquid-crystalline polymers(LCPs).The periodically ordered nanostructures in bulk film of LCBCs can be acquired by supramolecular cooperative motion,derived from the interaction between liquid-crystalline elastic deformation and microphase separation,which are able to improve physical properties of polymer film toward advanced functional ***,various micro/nano-patterned structures have been fabricated via light manipulation of photoresponsive LCBCs with good reproducibility and mass *** to recent developments in synthesis and polymerization techniques,diverse azobenzene-containing LCBCs have been designed,resulting in the creation of a wide variety of novel *** review illustrates recent progresses in macroscopic regulation of hierarchical nanostructures in LCBCs towards functional *** existing challenges are also discussed,showing perspectives for future studies.

关键词： Liquid-crystalline block copolymers Microphase separation Hierarchical nanostructures Functional materials

Homologous CoS2 interface with directed electron transfer and strong chloridion repulsion for efficient seawater oxidation

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Science China Chemistry 2025年

作者： Yuan Tian Jiang-Bo Chen Jie Ying Ge Tian Yu-xuan Xiao Yi Lu Si-Ming Wu Wei Geng Ling Shen Xiao-Yu Yang State Key Laboratory of Advanced Technology for Materials Synthesis and Processing and School of Materials Science and Engineering and Shenzhen Research Institute & Laoshan Laboratory Wuhan University of Technology School of Chemical Engineering and Technology Sun Yat-Sen University National Energy Key Laboratory for New Hydrogen-Ammonia Energy Technologies Foshan Xianhu Laboratory

Seawater electrolysis is a highly promising method to produce high energy density hydrogen,especially in dry areas that have scarce freshwater ***,application of seawater electrolysis is confronted by two major problems associated with catalysts employed for the anodic oxygen evolution reaction （OER） including the competitive hypochlorite evolution reaction（HCER） and strong chloridion （Cl–） triggered *** studies aimed at overcoming these problems,a facile method has been developed to synthesize a homologous CoS2heterojunction as an OER *** to a difference in work functions at the interface and increased electron density,this material has directed electron transfer and strong chloridion repulsion properties,*** have shown that CoS2achieves low overpotentials of 289 and 322 mV at 10 mA cm-2current density in respective alkaline （1 M KOH） and alkaline simulated seawater ***,the outstanding stability of CoS2is reflected in a negligible decline in activity during promotion of the OER for 100 *** of density functional theory calculations reveal that the homologous CoS2heterojunction promotes directed electron transport for optimizing adsorption/desorption of reactive species and heightens the Cl-adsorption energy for strongly repulsing Cl-,phenomena that enhance OER performance in alkaline simulated seawater.

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窟野河流域次降雨事件下水沙变化特征及其输移过程

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水土保持研究 2025年第2期32卷 52-60页

作者：杨晨佘冬立黄萱河海大学农业科学与工程学院南京211100

[目的]深入分析黄土高原粗沙区流域次降雨事件尺度下水沙动态变化特征及其输移过程,为黄土高原粗沙区流域的水沙管理和调控提供重要科学依据。[方法]以黄土高原中游粗沙多沙区窟野河流域为对象,收集2006—2019年间的160场次降雨事件水... 详细信息

[目的]深入分析黄土高原粗沙区流域次降雨事件尺度下水沙动态变化特征及其输移过程,为黄土高原粗沙区流域的水沙管理和调控提供重要科学依据。[方法]以黄土高原中游粗沙多沙区窟野河流域为对象,收集2006—2019年间的160场次降雨事件水沙数据。通过运用方差分析、水沙关系曲线、滞后分析等方法,比较位于窟野河及其子流域次降雨事件下产流输沙特征,构建了各流域次降雨事件尺度下水沙关系曲线,分析了水沙滞后关系及滞后指数的空间差异,以揭示次降雨尺度下窟野河流域的水沙输移过程。[结果](1)4个流域径流相关参数无显著差异,但泥沙相关参数差异显著;(2)位于窟野河上游东部的新庙流域水沙相关性强,表征外界人为干扰的参数(a)最大,位于上游西部的王道恒塔流域泥沙浓度低,水沙相关性弱,表征河流本身输沙能力的参数(b)最大;(3)新庙、王道恒塔和温家川3个流域的主要滞后模式为逆时针型,泥沙来源于上游区域,且高含沙降雨事件的滞后系数(HI)平均值多为负;而神木流域的主要滞后模式为“8”字型,指示泥沙来源相对接近流域出口,且高含沙降雨事件的HI平均值多为正。[结论]窟野河嵌套流域次降雨事件尺度下水沙变化空间差异显著,泥沙输移过程复杂,不同子流域滞后模式揭示了泥沙来源和输移机制的空间异质性。

关键词：次降雨事件尺度输移过程水沙关系滞后分析

Optimization Study on Expansion Energy Used Air-Powered Vehicle with Pneumatic-Hydraulic Transmission

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Chinese Journal of Mechanical Engineering 2018年第1期31卷 220-229页

作者： Xiang-Heng Fu Mao-Lin cai Yi-xuan Wang Yan Shi School of Automation Science and Electrical Engineering Beihang University The State Key Laboratory of Fluid Power & Mechatronic Systems Zhejiang University

Pneumatic-hydraulic transmission has been developed for years. However, its dynamic properties are not good enough for application. In this paper, in order to increase the output characteristics, a late-model air-powered vehicle using expansion energy is proposed which can boost energy through a pneumatic-hydraulic transmission. The dynamic characteristics of the air-powered vehicle is modeled and verified by conducting experiment. In addition,the influence of the key parameters of the air-powered vehicle is researched for the optimization of the system performance. Through the results, the author got the conclusion that, firstly, comparison of the results of model and experiment proves the built model to be effective; secondly, input air pressure should be set according to the request of the practical loads, and range of 0.65 to 0.75 MPa can be chosen; thirdly, as a key structure parameter of the airpowered vehicle, ratio of the areas is considered to be set to approximate 8; what’s more, a bigger orifice with a limit will promote the system dynamic characteristic property, and the limit is about 3.5 mm; last but not the least, not too farther position of the rings will increase the quality of output dynamic characteristics. This paper can be a reference for system design of air-powered vehicle and dynamic improvement.

关键词： Air-powered vehicle Expansion energy Pneumatic-hydraulic transmission Output dynamic characteristics

FAM53B promotes pancreatic ductal adenocarcinoma metastasis by regulating macrophage M2 polarization

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World Journal of Gastrointestinal Oncology 2024年第4期16卷 1479-1499页

作者： xuan-Zeng pei Min cai Da-Wei Jiang Song-Hai Chen Qing-Qing Wang Hui-Min Lu Yi-Fan Lu Department of Hepatological Surgery The First Hospital of JiaxingJiaxing 314000Zhejiang ProvinceChina Department of General Surgery West China Hospital of Sichuan UniversityChengdu 610044Sichuan ProvinceChina

BACKGROUND Our study investigated the role of FAM53B in regulating macrophage M2 polarization and its potential mechanisms in promoting pancreatic ductal adenocarcinoma(PDAC)*** To further investigate the role of FAM53B in regulating macrophage M2 polarization and its potential mechanism in promoting PDAC *** goal is to determine how FAM53B affects macrophage M2 polarization and to define its underlying mechanism in PDAC *** Cell culture and various experiments,including protein analysis,immunohisto-chemistry,and animal model experiments,were *** compared FAM53B expression between PDAC tissues and healthy tissues and assessed the correlation of FAM53B expression with clinical *** study analyzed the role of FAM53B in macrophage M2 polarization in vitro by examining the expression of relevant ***,we used a murine model to study the role of FAM53B in PDAC metastasis and analyzed the potential underlying *** Our research showed that there was a significant increase in FAM53B levels in PDAC tissues,which was linked to adverse tumor *** findings indicated that FAM53B can enhance macrophage M2 polarization,leading to increased anti-inflammatory factor *** results from the mouse model further supported the role of FAM53B in PDAC metastasis,as blocking FAM53B prevented tumor cell invasion and *** FAM53B promotes PDAC metastasis by regulating macrophage M2 *** discovery could lead to the development of new strategies for treating *** example,interfering with the FAM53B signaling pathway may prevent cancer *** research findings also provide important information for expanding our understanding of PDAC pathogenesis.

关键词： FAM53B Pancreatic ductal adenocarcinoma Tumor metastasis Macrophage polarization

Enhanced electromagnetic wave absorption property of binary ZnO/NiCo_(2)O_(4) composites

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Journal of Advanced Ceramics 2021年第4期10卷 832-842页

作者： Bin DU Mei cai xuan WANG Junjie QIAN Chao HE Anze SHUI School of Materials Science and Engineering South China University of TechnologyGuangzhou 510641China

Nowadays,metal oxide-based electromagnetic wave absorbing materials have aroused widely attentions in the application of telecommunication and electronics due to their selectable mechanical and outstanding dielectric ***,the binary ZnO/NiCo_(2)O_(4) nanoparticles were successfully synthesized via hydrothermal reaction and the electromagnetic wave absorption properties of the composites were investigated in *** a result,benefiting from the dielectric loss,the as-obtained ZnO/NiCo_(2)O_(4)-7 samples possessed a minimum reflection loss value of-33.49 dB at 18.0 GHz with the thickness of 4.99 *** work indicates that ZnO/NiCo_(2)O_(4) composites have the promising candidate applications in electromagnetic wave absorption materials in the future.

关键词： ZnO particles dielectric loss magnetic loss electromagnetic wave absorption

The Bioprospecting of Microbial-Derived Antimicrobial Peptides for Sustainable Agriculture

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Engineering 2023年第8期27卷 222-233页

作者： Shuhua Lin xuan Chen Huimin Chen Xixi cai Xu Chen Shaoyun Wang College of Chemical Engineering Fuzhou UniversityFuzhou 350108China College of Biological Science and Engineering Fuzhou UniversityFuzhou 350108China

Strategies aimed at defining,discovering,and developing alternatives to traditional antibiotics will underlie the development of sustainable agricultural *** such strategies,antimicrobial peptides(AMPs)with broad-spectrum antimicrobial activity and multifaceted mechanisms of action are recognized as ideal alternatives in the post-antibiotic *** particular,AMPs derived from microbes with active metabolisms that can adapt to a variety of extreme environments have long been sought ***,this review summarizes information on naturally occurring AMPs,including their biological activity,antimicrobial mechanisms,and the preparation of microbial-derived AMPs;it also outlines their applications and the challenges presented by their use in the *** dissecting the research results on microbial-derived AMPs of previous generations,this study contributes valuable knowledge on the exploration and realization of the applications of AMPs in sustainable agriculture.

关键词： Antibiotic alternatives Microbial-derived AMPs Sustainable agricultural systems

Investigation of Nuclear Binding Energy and Charge Radius Based on Random Forest Algorithm

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原子能科学技术 2023年第4期57卷 704-712页

作者： cai Boshuai YU Tianjun LIN xuan ZHANG Jilong WANG Zhixuan YUAN Cenxi Sino-French Institute of Nuclear Engineering and Technology Sun Yat-sen UniversityZhuhai 519082China

The random forest algorithm was applied to study the nuclear binding energy and charge *** regularized root-mean-square of error(RMSE)was proposed to avoid overfitting during the training of random *** for nuclides with Z,N>7 is reduced to 0.816 MeV and 0.0200 fm compared with the six-term liquid drop model and a three-term nuclear charge radius formula,*** interest is in the possible(sub)shells among the superheavy region,which is important for searching for new elements and the island of *** significance of shell features estimated by the so-called shapely additive explanation method suggests(Z,N)=(92,142)and(98,156)as possible subshells indicated by the binding *** the present observed data is far from the N=184 shell,which is suggested by mean-field investigations,its shell effect is not predicted based on present *** significance analysis of the nuclear charge radius suggests Z=92 and N=136 as possible *** effect is verified by the shell-corrected nuclear charge radius model.

关键词： nuclear binding energy nuclear charge radius random forest algorithm