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Digital Earth: decadal experiences and some thoughts

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International Journal of Digital Earth 2010年第1期3卷 31-46页

作者： h.D.Guo Z.liu l.W.zhu Center for Earth Observation and Digital Earth Chinese Academy of SciencesNo.9 Beiyitiao RoadZhongguancunHaidian DistrictBeijing 100190China

The understanding that mankind should reasonably exploit and utilize earth resources and effectively protect the planet on which we live,is now widely ***,effective actions can only be conducted if we better understand and visualize the *** meet this need,digital earth science and technology have been put forward and *** paper introduces the evolution and development process of digital earth,and presents an overview by reviewing and analyzing the 1999 and 2009 Beijing Declaration on Digital Earth,the scientific and commercial digital earth systems,global and regional digital earth research,and some existing platforms of digital earth *** also presents some thoughts about digital earth’s future development.

关键词： Beijing Declaration digital earth system global change

Parameter influence on electron collection efficiency of a bare electrodynamic tether

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Science China(Information Sciences) 2018年第2期61卷 24-35页

作者： Gangqiang lI Zheng h.zhu Department of Earth and Space Science and Engineering York University Department of Mechanical Engineering York University

This study develops a coupled multiphysics finite element method for the dynamic analysis of a bare flexible electrodynamic tether. Contrary to the existing methods, the new method discretizes and solves the orbital motion limited equation and the dynamic equation of an elastic flexible tether ***, the new method is verified via comparison with the existing methods in a straight tether ***, the number of tether elements, tether bending deformation, and two design parameters at the cathodic end affecting the electrical current are investigated. It is determined that the tether bending deformation and the two parameters i.e., the impedance ZT and ΦPWhave a significant impact on the electron collection efficiency of an electrodynamic tether system. The results indicate that the proposed method should be applied in the refined mission analysis.

关键词： multiphysics coupled finite element electrodynamic tether electron collection efficiency

Effects on the mixing process of a coiled tube after a T-junction:Simulation and correlation

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Chinese Journal of Chemical Engineering 2018年第12期26卷 2441-2447页

作者： Shan zhu Kai Wang Yangcheng lü State Key laboratory of Chemical Engineering Department of Chemical Engineering Tsinghua University

Simulations were performed to examine the effects of a coiled tube after a T-junction on the mixing and flow characteristics. A coiled tube was found to have two effects: inducing a radial flow and flattening the axial velocity distribution, which enhances and weakens the mixing, respectively. In the straight tube section connecting the Tjunction and coiled tube, the latter may dominate and cause the mixing to deteriorate. An experiment was performed with the Villermaux/Dushman method to verify the simulation results. Based on a mixing performance simulation with various fluid and geometric structure parameters, a dimensionless correlation was obtained that can be used to determine the mixing intensity along the coiled tube with a deviation of less than 1.5%.These results provide guidance for designing a coiled tube or optimizing the operating conditions to meet the mixing requirements of specific chemical processes.

关键词： Mixing T-junction Simulation Coiled tube Correlation Flow

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太湖底泥磷释放量及释放规律的研究综述

湖泊科学 2025年第1期37卷 14-35页

作者：朱伟侯豪刘环许小格朱瑜星陈诺曹俊林乃喜河海大学环境学院南京210098 河海大学土木与交通学院南京210098 河海大学水科学研究院南京210098

太湖是我国最为重要的湖泊之一,是国家湖泊治理的重点。自2007年水危机以来,太湖治理累计投入超2620亿元,是世界上治理力度最大的湖泊。2016年以来太湖出现磷反弹,2020年开始显著好转,2023年水华减少。太湖蓝藻水华与磷的响应相对显著,... 详细信息

太湖是我国最为重要的湖泊之一,是国家湖泊治理的重点。自2007年水危机以来,太湖治理累计投入超2620亿元,是世界上治理力度最大的湖泊。2016年以来太湖出现磷反弹,2020年开始显著好转,2023年水华减少。太湖蓝藻水华与磷的响应相对显著,回顾太湖磷十余年来的研究,关于底泥内源释放对水体总磷贡献的说法不一,这对于太湖整体磷负荷的认识及内源治理措施的制定产生了重要影响。针对太湖底泥磷的源汇、释放量以及释放规律,本文对国内外关于湖泊底泥磷释放的监测、实验、计算等研究进行系统回顾,对关于太湖底泥释放方面的研究进行梳理。通过比较和分析,尝试形成对太湖底泥磷释放规律和范围的一些基本认识。通过综述总结提出了“总源”“总汇”“净源”“净汇”的概念,并对可能成为“净源”的5个过程的发生条件和释放强度进行分析。认为Fick扩散释放是可以恒常性发生的过程,而在具备条件才发生的过程中,DOl后出现的磷还原释放是比较主要的过程,需要重点关注。“净源”是否发生应该依据实际湖泊的环境条件开展动态释放实验来判断。太湖目前虽然处于“总汇”状态,但“净源”是显著存在的,明确“净源”存在的位置和发生的时段对于太湖内源治理非常重要。

关键词：太湖底泥磷释放源汇质量平衡释放实验

Microstructural Dependence of Damping Behaviour of Eutectoid Zn-Al Based Alloy (ZA27)──Discussion of "Damping Behaviour and Mechanism of Graphite Particulate Reinforced Metal Matrix Composites

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Journal of Materials Science & Technology 1999年第2期15卷 178-180页

作者： zhu, Y.h. Institute de Investigaciones en Materiales UNAM Mexico D.F. 04510 Apart.P.70-360 Mexico Dept. of Manufacturing Engineering Hong Kong Polytechnic University Hong Kong

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中国改革中的渐进主义和国家集权的作用

国外社会科学 1997年第1期 85-86页

作者：Ｌ．Ｈ．利乌

中国改革中的渐进主义和国家集权的作用〔澳〕Ｌ．Ｈ．利乌在强调分权化和加强市场作用观点为主流的理论讨论中，一些政治学家赞同在经济改革中加强政府的集权功能和实行渐进主义政策。中国与其他前共产主义国家相比，改革的成就是显而... 详细信息

中国改革中的渐进主义和国家集权的作用〔澳〕Ｌ．Ｈ．利乌在强调分权化和加强市场作用观点为主流的理论讨论中，一些政治学家赞同在经济改革中加强政府的集权功能和实行渐进主义政策。中国与其他前共产主义国家相比，改革的成就是显而易见的。本文就此强调了有力的中央政...

关键词：渐进主义中央政府分权化通货膨胀中华人民共和国

Analysis of interlaminar stress and nonlinear dynamic response for composite laminated plates with interfacial damage

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Acta Mechanica Sinica 2008年第6期24卷 709-720页

作者： F.h.zhu .M.Fu College of Mechanics and Aerospace Hunan University410082 ChangshaChina

By considering the effect of interfacial damage and using the variation principle, three-dimensional nonlinear dynamic governing equations of the laminated plates with interfacial damage are derived based on the general sixdegrees-of-freedom plate theory towards the accurate stress analysis. The solutions of interlaminar stress and nonlinear dynamic response for a simply supported laminated plate with interfacial damage are obtained by using the finite difference method, and the results are validated by comparison with the solution of nonlinear finite element method. In numerical calculations, the effects of interfacial damage on the stress in the interface and the nonlinear dynamic response of laminated plates are discussed.

关键词： laminated plates Geometric nonlinearity Accurate stress analysis Interfacial damage Interlaminar stress Nonlinear dynamic response

Improving cyclic oxidation resistance of Ni_(3)Al-based single crystal superalloy with low-diffusion platinum-modified aluminide coating

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Journal of Materials Science & Technology 2020年第19期54卷 132-143页

作者： h.liu M.M.Xu S.li Z.B.Bao S.l.zhu F.h.Wang Institute of Metal Research Chinese Academy of SciencesWencui Road 62#Shenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaJinzhai Road 96#Hefei 230026China Shenyang National laboratory for Materials Science Northeastern UniversityWenhua Road 3#Shenyang 110819China

A low-diffusion Ni Re Pt Al coating((Ni,Pt)Al outer layer in addition to a Re-rich diffusion barrier layer)was prepared on a Ni_(3)Al-base single crystal(SC)superalloy via electroplating and gaseous aluminizing treatments,wherein the electroplating procedures consisted of the composite deposition of Ni-Re followed by electroplating of *** order to perform a comparison with conventional Ni Al and(Ni,Pt)Al coatings,the cyclic oxidation performance of the Ni Re Pt Al coating was evaluated at 1100 and 1150℃.We observed that the oxidation resistance of the Ni Re Pt Al coating was significantly improved by the greater presence of the residualβ-Ni Al phase in the outer layer and the lesser outward-diffusion of Mo from the *** addition,the coating with the Re-rich diffusion barrier demonstrated a lower extent of interdiffusion into the substrate,where the thickness of the second reaction zone(SRZ)in the substrate alloy decreased by 25%.The mechanisms responsible for improving the oxidation resistance and decreasing the extent of SRZ formation are discussed,in which a particular attention is paid to the inhibition of the outward diffusion of Mo by the Re-based diffusion barrier.

关键词： Ni_(3)Al-base superalloy Pt-modified aluminide coating Re-rich diffusion barrier Cyclic oxidation Interdiffusion Second reaction zone

Peri-centrosomal localization of small interfering RNAs in C. elegans

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Science China life Sciences 2025年

作者： Qile Jin Xuezhu Feng Minjie hong Ke Wang Xiangyang Chen Jiewei Cheng Yan Kuang Xiaoyue Si Mingjing Xu Xinya huang Shouhong Guang Chengming zhu Department of Obstetrics and Gynecology The First Affiliated Hospital of USTC The USTC RNA Institute Hefei National Research Center for Physical Sciences at the Microscale School of Life Sciences Division of Life Sciences and Medicine Biomedical Sciences and Health Laboratory of Anhui Province University of Science and Technology of China School of Basic Medicine Anhui Medical University

The centrosome is the microtubule-organizing center and a crucial part of cell division. Centrosomal RNAs(cnRNAs) have been reported to enable precise spatiotemporal control of gene expression during cell division in many species. Whether and how cnRNAs exist in C. elegans are unclear. here, using the nuclear RNAi Argonaute protein NRDE-3 as a reporter, we observed potential peri-centrosome localized small interfering(si)RNAs in C. elegans. NRDE-3 was previously shown to associate with pre-mRNAs and pre-rRNAs via a process involving the presence of complementary siRNAs. We generated a GFP-NRDE-3 knock-in transgene through CRISPR/Cas9 technology and observed that NRDE-3 formed peri-centrosomal foci neighboring the tubulin protein TBB-2, other centriole proteins and pericentriolar material(PCM)components in C. elegans embryos. The peri-centrosomal accumulation of NRDE-3 depends on RNA-dependent RNA polymerase(RdRP)-synthesized 22G siRNAs and the PAZ domain of NRDE-3, which is essential for siRNA binding. Mutation of eri-1, ergo-1, or drh-3 significantly increased the percentage of pericentrosome-enriched NRDE-3. At the metaphase of the cell cycle, NRDE-3 was enriched in both the peri-centrosomal region and the spindle. Moreover, the integrity of centriole proteins and pericentriolar material(PCM) components is also required for the peri-centrosomal accumulation of NRDE-3. Therefore, we concluded that siRNAs could accumulate in the pericentrosomal region in C. elegans and suggested that the peri-centrosomal region may also be a platform for RNAi-mediated gene regulation.

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