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Spatial-temporal Characteristics of Green Development Efficiency and Influencing Factors in Restricted Development zones:A Case Study of Jilin province,China

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Chinese Geographical Science 2020年第4期30卷 736-748页

作者： LI ping TONG Lianjun guo Yanhua guo Fuyou Northeast Institute of Geography and Agroecology Chinese Academy of SciencesChangchun 130102China University of Chinese Academy of Sciences Beijing 100049China Urban Development Institute Jilin Province Academy of Social SciencesChangchun 130000China College of Geographical Science Northeast Normal UniversityChangchun 130024China College of Geography and Tourism Qufu Normal UniversityRizhao 276826China

Green development is an important issue of sustainable development in *** to the relatively backward economy and the fragile ecological environment,restricted development zones need to embrace green *** 38 counties in Jilin province as the empirical research objects,and based on cross-sectional data for each county in 2005,2010,and 2015,we accurately depicted the spatiotemporal evolutionary characteristics of green development efficiency(GDE)in restricted development zones of Jilin province using the slacks-based measure-data envelope analysis(SBM-DEA)***,the factors that influence GDE were further analyzed using the Tobit *** found that:first,GDE showed a V-shaped trend in restricted development zones of Jilin *** differences in GDE in the eastern,central,and western Jilin province increased ***,76%of counties in the restricted development zones had high or higher *** resource-based cities were the main areas with low or lower ***,the economic development level was the core factor affecting *** level had a significant negative effect on GDE in the restricted development *** effect of technological innovation level on GDE fluctuated,and we found that a‘backward mechanism’of technological innovation was beginning to *** structure and environmental governance had no significant effects on GDE.

关键词： green development efficiency spatiotemporal evolution influencing factor restricted development zones Jilin province

Microstructure Development of Directionally Solidified Nb-Ti-Si Based Ultrahigh Temperature Alloy

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稀有金属材料与工程 2009年第A03期38卷 24-27页

作者： guo Haisheng guo Xiping Yao Chengfang State Key Laboratory of Solidification processing Northwestern Polytechnical University Xi＇an 710072 China

Integrally directional solidification of an Nb-Ti-Si based ultrahigh temperature alloy was performed in an ultrahigh temperature and high thermal gradient furnace with the use of ceramic crucibles. The microstructural evolution with the withdrawing rate increasing during directional solidification was revealed. The integrally directionally solidified microstructure was composed of couple grown lamellar (Nbss+(Nb,X)5Si3) eutectic colonies and a few hexagonally cross-sectioned (Nb,X)5Si3 columns (X represents Ti and Hf elements). All the directionally solidified microstructure was straightly aligned along the longitudinal axis of the specimens. With increasing of the withdrawing rate, the average diameter of the eutectic cells and inter lamella spacings in the eutectic cell decreased. The near-planar solid/liquid interface appeared when the withdrawing rate was 1μm/s, and the cellular solid/liquid interface formed when the withdrawing rate was 5 μm/s.

关键词：超高温合金物理性能热梯度定向凝固组织

STRONG N-DISCOUNT AND FINITE-HORIzON OpTIMALITY FOR CONTINUOUS-TIME MARKOV DECISION pROCESSES

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Journal of Systems Science & Complexity 2014年第5期27卷 1045-1063页

作者： zHU Quanxin guo Xianping School of Mathematical Sciences and Institute of Finance and Statistics Nanjing Normal University School of Mathematics and Computational Science Zhongshan University

This paper studies the strong n(n =—1,0)-discount and finite horizon criteria for continuoustime Markov decision processes in polish *** corresponding transition rates are allowed to be unbounded,and the reward rates may have neither upper nor lower *** mild conditions,the authors prove the existence of strong n(n =—1,0)-discount optimal stationary policies by developing two equivalence relations:One is between the standard expected average reward and strong—1-discount optimality,and the other is between the bias and strong 0-discount *** authors also prove the existence of an optimal policy for a finite horizon control problem by developing an interesting characterization of a canonical triplet.

关键词： Continuous-time Markov decision process expected average reward criterion finite-horizon optimality polish space strong n-discount optimality

Biomimetic Janus paper with Controllable Swelling for Shape Memory and Energy Conversion

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Journal of Bionic Engineering 2019年第1期16卷 1-12页

作者： pan Tian zhiguang guo Hubei Collaborative Innovation Centre for Advanced Organic Chemical Materials and Ministry of Education Key Laboratory for the Green preparation and Application of Functional Materials Hubei UniversityWuhan 430062China State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of Sciences Lanzhou 730070China

Being inspired by the "seismonastic reaction"of Mimosa pudica,an asymmetric swelling system was constructed to induce the controllable directional deformation of filter *** this work,multifunctional biomimetic Janus paper was facilely fabricated via depositing poly(vinylidene fluoride)(pVDF)on one side of Qualitative Filter paper (QFp),the permeation of polymer solutions within filter paper was well controlled during *** wetting and swelling behavior of the prepared Janus paper were *** Janus paper showed controllable swelling-induced deformations in *** the degree and orientation of the deformation were fully *** the one hand,the degree of deformation depends on the gradient wettability and hygroscopicity of the Janus paper,on the other hand,the orientation of deformation is related to the storage and release of ***,the steady deformation during swelling endows the Janus paper with novel shape memory property both under idling and loading *** Janus paper was also applied to achieve reversible energy conversion from the swelling potential energy to mechanical potential energy.

关键词： Janus paper swelling shape memory energy conversion

Double drumheadlike surface states in elemental group Ⅴ nodal line semimetals

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Nano Research 2020年第4期13卷 927-931页

作者： Yang Hang Wanlin guo State Key Laboratory of Mechanics and Control of Mechanical Structures Key Laboratory for Intelligent Nano Materials and Devices of Ministry of Educationand Institute of NanoscienceNanjing University of Aeronautics and AstronauticsNanjing 210016China

Drumheadlike surface states are typical characteristics in nodal line semimetals and bring varieties of unusual attractive *** we demonstrate the double drumheadlike surface states in group V elemental semimetals As,Sb,Bi,which family materials behave a nodal line topology with a 3D flowerlike nodal line,using first-principles ***(001)surface of group V elemental semimetals,the projection pattern of the nodal line overlaps and a complicated double drumheadlike surface state appears inside the overlapped *** double surface state is widely distributed on the surface region up to a penetration depth of 3.5 nm,which is much deeper than the depth of single surface state on(111)*** that the simplicity of the elemental structure and the small gap induced by the spin orbit coupling,this family materials are promising candidates for the experimental observation of the novel double drumheadlike surface state.

关键词： double drumheadlike surface states nodal line semimetals elemental materials electronic structure

Research and Development of Electronic and Optoelectronic Materials in China

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Journal of Semiconductors 2000年第11期21卷 1041-1049页

作者： WANG zhan\|guo(z.G.Wang (Laboratory of Semiconductor Materials Science, Institute of Semiconductors, The Chinese Academy of Sciences, Beijing\ 100083, China) Lab. of Semicond. Mater. Sci. Inst. of Semiconductors Chinese Acad. of Sci. Beijing 100083 China

A review on the research and development of electronic and optoelectronic materials in China, including the main scientific activities in this field, is presented. The state\|of\|the\|arts and prospects of the electronic and optoelectronic materials in China are briefly introduced, such as those of silicon crystals, compound semiconductors, synthetic crystals,especially nonlinear optical crystals and rare\|earth permanent magnets materials, etc., with a greater emphasis on Chinese scientist’s contributions to the frontier area of nanomaterials and nanostructures in the past few years. A new concept of the trip chemistry proposed by *** zhongfan from peking University has also been described. Finally the possible research grants and the national policy to support the scientific research have been discussed.

关键词：电子材料光电子材料压力材料研究进展

Design of a Servo Mechanical press with Redundant Actuation

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Chinese Journal of Mechanical Engineering 2009年第4期22卷 574-579页

作者： guo Weizhong GAO Feng State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong University Shanghai 200240 China

A servo press is a new type of mechanical press that is driven by programmable motors and offers superior performance such as low noise, excellent efficiency and high precision for metal forming operations. Similar to multi-link mechanical presses, a servo mechanical press tends to grow in size as the tonnage increases that calls for larger, heavy duty servo motors, which could be expensive and may not even be available. In this paper, a new concept of servo mechanical press with redundant actuation is proposed firstly using two servo motors driving one input shaft, i.e. one-point-two-motor mode that makes it possible to produce a larger press with available servomotors. Then the punching mechanism design is detailed. The performance indices are set up including mechanical advantage reciprocal and link force ratios. A bounded feasible solution space is constructed for dimensional synthesis based on non-dimensional link lengths and assembly conditions. The performance atlases are depicted over the bounded feasible solution space that lead to a visual solution of the punching mechanism with global optimization. Finally, case studies are given to illustrate the design method with visual global optimization, and a prototype with 200 t punching force is being developed in our laboratory to demonstrate efficacy of the new concept for servo mechanical press. The presented research provides a feasible solution to the development of heavy-duty servo mechanical presses and finds potential applications in the development of other types of heavy equipments with electric drive.

关键词： servo mechanical press redundant actuation mechanism design visual global optimization prototype

Distribution of static equilibrium points in static electric field produced by fixed electrons

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The Journal of China Universities of posts and Telecommunications 2014年第4期21卷 92-95页

作者： guo Feng School of Science China University Mining & Technology(Beijing)

Fix n electrons on the disk ｜z｜≤R. They generate a static electric field. Let a be an electron located in the disk ｜z｜≤R sin π/n. It shows that the closed disk with center a and radius R contains at least one s... 详细信息

关键词： fixed electrons static electric field static equilibrium points

Spherical packing Superlattices in Self-Assembly of Homogenous Soft Matter:progresses and potentials

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Chinese Journal of polymer Science 2023年第5期41卷 607-620,I0005页

作者： Yuchu Liu Huanyu Lei Qing-Yun guo Xianyou Liu Xinghan Li Yuean Wu Weiyi Li Wei zhang Geng Xin Liu Xiao-Yun Yan Stephen z.D.Cheng South China Advanced Institute for Soft Matter Science and Technology School of Molecular Science and EngineeringSouth China University of TechnologyGuangzhou 510640China School of polymer Science and polymer Engineering The University of AkronAkron OH 44325-3909USA State Key Laboratory for Modification of Chemical Fibers and polymer Materials Center for Advanced Low-dimension MaterialsCollege of Material Science and EngineeringDonghua UniversityShanghai 201620China

The construction of complex superlattices using homogenous soft matter has great potential for the bottom-up fabrication of complex,nanoscale *** topic is not only interested in scientific exploring for new concepts of supramolecular crystals with nanometer in sizes,which is about thousand times larger in volumes than those of normal crystals,but also practically important to provide construction principles of metamaterials which are artificially structured materials for controlling and manipulating light,sound,and other physical *** systems have fast assembly kinetics and convenient processing procedures,making them ideal for large-scale superlattice *** this perspective,we focus on recent developments in the construction of complex spherical packing superlattices using homogenous soft *** discuss the general mechanism of those formations of supramolecular motifs and provide an overview of the spherical packing superlattices self-assembled by homogenous soft matters based on different volume ***,we outline the potentials of utilizing this approach in constructing novel superlattices as well as its future challenges.

关键词： Soft matter Self-assembly Spherical packing phases Superlattice Bottom-up construction