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Distributed Least-Squares Iterative Methods in Large-Scale networks:A Survey

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中兴通讯技术：英文版 2017年第3期15卷 37-45页

作者： SHI Lei ZHAO Liang SONG Wenzhan Goutham Kamath WU Yuan LIU Xuefeng Georgia state university Atlanta GA 30302 USA Georgia Gwinnett College Lawrenceville GA 30043 USA university of Georgia Athens GA 30602 USA Zhejiang university of Technology Hangzhou 310023 China The Hong Kong Polytechnic university Hong Kong China

Many science and engineering applications involve solvinga linear least-squares system formed from some field measurements. In the distributed cyber-physical systems(CPS),each sensor node used for measurement often only knowspartial independent rows of the least-squares system. To solve the least-squares all the measurements must be gathered at a centralized location and then perform the computa-tion. Such data collection and computation are inefficient because of bandwidth and time constraints and sometimes areinfeasible because of data privacy concerns. Iterative methods are natural candidates for solving the aforementionedproblem and there are many studies regarding this. However,most of the proposed solutions are related to centralized/parallel computations while only a few have the potential to beapplied in distributed networks. Thus distributed computations are strongly preferred or demanded in many of the realworld applications, e.g. smart-grid, target tracking, etc. Thispaper surveys the representative iterative methods for distributed least-squares in networks.

关键词： distributed computing iterative methods least⁃squares mesh network

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木质素聚氨酯涂料的研究进展

现代化工 2024年第5期44卷 48-53页

作者：王丽云龙马建波庄文平赵锡润郭宗伟吕高金齐鲁工业大学(山东省科学院)生物基材料与绿色造纸国家重点实验室山东济南250353 山东龙德复合材料科技股份有限公司山东潍坊262699 临朐玉龙造纸有限公司山东潍坊262600

对近年来木质素聚氨酯涂料的研究进展进行了综述。介绍了木质素的结构和不同种类木质素聚氨酯涂料。针对木质素聚氨酯涂料制备过程中存在的问题,从木质素的分离和改性以及如何与异氰酸酯更好地聚合等方面提出了展望,以期为木质素在聚氨... 详细信息

对近年来木质素聚氨酯涂料的研究进展进行了综述。介绍了木质素的结构和不同种类木质素聚氨酯涂料。针对木质素聚氨酯涂料制备过程中存在的问题,从木质素的分离和改性以及如何与异氰酸酯更好地聚合等方面提出了展望,以期为木质素在聚氨酯涂料领域的高效利用提供有益参考。

关键词：木质素化学改性聚氨酯涂料

Precise fabrication of single-atom alloy co-catalyst with optimal charge state for enhanced photocatalysis

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National Science Review 2021年第1期8卷 81-88页

作者： Yating Pan Yunyang Qian Xusheng Zheng Sheng-Qi Chu Yijun Yang Chunmei Ding xi Wang Shu-Hong Yu Hai-Long Jiang Hefei National laboratory for Physical Sciences at the Microscale CAS Key Laboratory of Soft Matter ChemistryDepartment of Chemistry University of Science and Technology of China National Synchrotron Radiation laboratory (NSRL) University of Science and Technology of China Beijing Synchrotron Radiation Facility Institute of High Energy PhysicsChinese Academy of Sciences Key laboratory of Luminescence and Optical Information Ministry of EducationDepartment of Physics School of Science Beijing Jiaotong University Dalian National laboratory for Clean Energy State Key Laboratory of Catalysis Dalian Institute of Chemical Physics Chinese Academy of Sciences

While the surface charge state of co-catalysts plays a critical role for boosting photocatalysis, studies on surface charge regulation via their precise structure control remain extremely rare. Herein, metal-organic framework（MOF） stabilized bimetallic Pd@Pt nanoparticles, which feature adjustable Pt coordination environment and a controlled structure from core-shell to single-atom alloy（SAA）, have been ***, apart from the formation of a Mott-Schottky junction in a conventional way, we elucidate that Pt surface charge regulation can be alternatively achieved by changing its coordination environment and the structure of the Pd@Pt co-catalyst, where the charge between Pd and Pt is redistributed. As a result, the optimized Pd;@Pt;/MOF composite, which involves an unprecedented SAA co-catalyst, exhibits exceptionally high photocatalytic hydrogen production activity, far surpassing its corresponding counterparts.

关键词： metal-organic framework (MOF) single-atom alloy (SAA) co-catalyst surface charge state photocatalysis

Powerful 2 μm Silica Fiber Sources: A Review of Recent Progress and Prospects

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Journal of Electronic Science and Technology 2015年第4期13卷 315-327页

作者： xiao-xi Jin xiong Wang Pu Zhou Hu xiao Ze-Jin Liu the College of Optoelectronic Science and Engineering National University of Defense Technology

A review on the progress of powerful 2 μm silica fiber sources in past decades is presented. We review the state-of-the-art records and representative achievements of 2 μm high-average-power continuous- wave, pulsed fiber lasers and amplifiers, and powerful superfluorescent sources. Challenges which limit the further power scaling of 2 μm silica fiber sources are discussed, including pumping brightness limitation, thermal problem and nonlinear effects. Potential and promising roadmaps to go beyond these limitations, like tandem pumping and beam combining, are discussed. Prospects of powerful 2 μm silica fiber sources are also presented in the end of paper.

关键词： Doped fiber amplifiers fiber lasers,high power amplifiers infrared spectra.

Bioreduction of hexavalent chromium:Effect of compost-derived humic acids and hematite

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Chinese Chemical Letters 2020年第10期31卷 2693-2697页

作者： Chao Yang Ming-xia Zheng Yuan Zhang Bei-Dou xi Zai-Feng Tian xiao-Song He School of Environmental Science and Engineering Tianjin UniversityTianjin 300350China state Environmental Protection Key laboratory of Simulation and Control of Groundwater Pollution Chinese Research Academy of Environmental SciencesBeijing 100012China state Key laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental SciencesBeijing 100012China Hebei Engineering Research Center for Geographic Information Application Institute of Geographical SciencesHebei Academy of SciencesShijiazhuang 050030China Hebei Provincial Academy of Ecological and Environmental Science Shijiazhuang 050037China

Composting can enhance the nutrie nt ele ments cycling and reduce carbon dioxide ***,little information is available regarding the application of compost for the remediation of the contaminated *** this study,we assess the response of the redox capacities(electron accepting capacities(EAC)and electron donating capacities(EDC))of compost-derived humic acids(HAs)to the bioreduction of hexavalent chromium(Cr(Ⅵ)),especially in presence of *** result showed that the compost-derived HAs played an important role in the bioreduction of Cr(Ⅵ)in presence and absence of hematite under the anoxic,neutral(pH 7)and motionless *** on the pseudo-first order kinetic model,the rate constants of Cr(Ⅵ)reduction increased by 1.3.-2.0 times when compost-derived HAs was *** redox capacity originating from the polysaccharide structure of compost-derived HAs made them effective in the direct Cr(Ⅵ)reduction(without MR-1)at pH ***,the reduction rates were inversely proportional to the composting treatment *** iron mineral(Fe_(2)O_(3.)and compost-derived HAs were both present,the rate constants of Cr(Ⅵ)reduction increased by 2.3.-5.09,which were higher than the rate of Cr(Ⅵ)reduction in HA-only systems,indicating that the hematite played a crucial role in the bioreduction process of Cr(Ⅵ).EAC and quinonoid structures played a major role in enhancing the bioreduction of Cr(Ⅵ)when iron mineral and compost-derived HAs coexisted in the *** results can extend the application fields of compost and will provide a new insight for the remediation of Cr(Ⅵ)-contaminated soil.

关键词： Bioreduction Hexavalent chromium Composting Humic acids Hematite

Progress of AFM single-cell and single-molecule morphology imaging

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Chinese Science Bulletin 2013年第26期58卷 3177-3182页

作者： LI Mi LIU LianQing xi Ning WANG YueChao DONG ZaiLi xiAO xiuBin ZHANG WeiJing state Key laboratory of Robotics Shenyang Institute of Automation Chinese Academy of Sciences university of Chinese Academy of Sciences Department of Mechanical and Biomedical Engineering City University of Hong Kong Department of Lymphoma Affiliated Hospital of Military Medical Academy of Sciences

Atomic force microscopy (AFM) can probe single living cells and single native membrane proteins in natural fluid environments with label-free high spatial resolution. It has thus become an important tool for cellular and molecular biology that significantly complements traditional biochemical and biophysical techniques such as optical and electron microscopy and X-ray crystallog-raphy. Imaging surface topography is the primary application of AFM in the life sciences. Since the early 1990s, researchers have used AFM to investigate morphological features of living cells and native membrane proteins with impressive results. Steady improvements in AFM techniques for imaging soft biological samples have greatly expanded its applications. Based on the authors' own research in AFM imaging of living cell morphologies, a review of sample preparation procedures for single-cell and single-molecule imaging experiments is presented, along with a summary of recent progress in AFM imaging of living cells and native membrane proteins. Finally, the challenges of AFM high-resolution imaging at the single-cell and single-molecule levels are discussed.

关键词：原子力显微镜成像实验分子形态单个活细胞生物物理技术高空间分辨率高分辨率成像生物样品

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苏州艺圃游人观景视点时空分布规律研究

园林 2024年第9期41卷 29-38页

作者：陈曦肖湘东任严钊谭立钟誉嘉苏州大学建筑学院苏州215127

园林文化遗产是凝聚地方建造技艺与文化蕴涵的物质载体。以苏州古典园林艺圃为例,剖析古典园林景观形态特征作用于游人时空分布的内在机理。借助Python爬虫爬取网络用户生成内容(User Generated Content,UGC),根据UGC影像数据所反映的... 详细信息

园林文化遗产是凝聚地方建造技艺与文化蕴涵的物质载体。以苏州古典园林艺圃为例,剖析古典园林景观形态特征作用于游人时空分布的内在机理。借助Python爬虫爬取网络用户生成内容(User Generated Content,UGC),根据UGC影像数据所反映的景观类型与观景视点进行信息提取与聚类分析。在此基础上,选取空间类型、景观偏好和季相表征为景观分析指标,将艺圃内各类景观形态特征与游人感知偏好指标间的相关性进行量化分析。初步结果表明,功能属性与空间类型、景观偏好类别、视线连通性、视域范围是影响游人空间分布的影响因子,植物季相特征构成了影响游人时空分布的主要因素。旨在科学量化游人观景视点的时空分布特征,深入解读游人的景观偏好及影响其观景行为时空分布的机制。

关键词：艺圃古典园林用户生成内容游人时空分布景观偏好

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Atom Response Theory of Nonlinear Optical Responses and Its Applications

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Chinese Journal of Structural Chemistry 2020年第12期39卷 2172-2181,2056页

作者： CHENG xi-Yue WHANGBO Myung-Hwan HONG Mao-Chun DENG Shui-Quan state Key laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China Fujian Provincial Key laboratory of Theoretical and Computational Chemistry Xiamen 361005China Department of Chemistry North Carolina State UniversityRaleighNC 27695-8204USA Fujian Science&Technology Innovation laboratory for Optoelectronic Information of china Fuzhou 350108China

Second-order nonlinear optical(NLO)crystalline materials are fundamentally and technologically important for their ability to double or triple the frequency of *** article provides a brief review of the atom response theory(ART)of NLO responses recently developed on the basis of the partial response functional *** ART analysis enables one to quantitatively evaluate the contributions of individual constituent atoms to the second harmonic generation(SHG)response of a NLO crystal material on the basis of first principles DFT *** general partitioning principles developed in our recent work provide the conceptual foundation for determining the functional motifs of SHG *** this mini review we will focus on the concepts and principles as well as on applications with *** practically important empirical rules resulting from the ART studies will also be reviewed.

关键词： atom response theory nonlinear optical materials functional motif first-principles calculation

Distinct structural characteristics define a new subfamily of Mycoplasma ferritin

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Chinese Chemical Letters 2022年第11期33卷 4952-4955页

作者： Wenming Wang xiaojia Liu Yajie Wang Yuan Wang Dan Fu Hongfang xi Yi Zhao Hongfei Wang Institute of Molecular Science Shanxi UniversityTaiyuan 030006China state Key laboratory of Medicinal Chemical Biology and College of Pharmacy Nankai UniversityTianjin 300350China Shanxi Key laboratory of Pharmaceutical Biotechnology Taiyuan 030006China

Ferritins can generally be divided into four subfamilies based on their structural characteristics,namely,the classic ferritins(Ftns),bacterioferritins(Bfrs),DNA-binding proteins from starved cells(Dps’),and encapsulated ferritins(Enc Ftns).However,the ferritin from Mycoplasma penetrans(Mpef)possesses a particular ferroxidase center with an extreme low activity and exhibits unusual characteristics,indicating that it could be a member of a quite different subfamily of ***,the crystal structure of the ferritin from Ureaplasma urealyticum(Uurf)is presented,Mpef and Uurf have very similar properties,though they display very low sequence ***,ferritins from Mycoplasma with these unique properties do not belong to any known subfamily,but they should rather be placed in a novel ferritin subfamily,which we term Mycoplasma Ferritin(Mfr).

关键词： Ferritin Ferritin subfamily Ureaplasma Mycoplasma Crystal structure