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Study on the Influence of Aspect Ratio on the Seismic Response and Overturning Resistance of a New Staggered Story Isolated Structure
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作者 Tiange Zhao Dewen Liu 《World Journal of Engineering and Technology》 2024年第3期617-634,共18页
The aspect ratio of the structure has a significant impact on the overall stability of the ultra high-rise building. A large aspect ratio of the structure increases the risk of overturning and reduces the lateral stif... The aspect ratio of the structure has a significant impact on the overall stability of the ultra high-rise building. A large aspect ratio of the structure increases the risk of overturning and reduces the lateral stiffness of the structure, leading to significant tensile and compressive stresses in the isolated bearings. To study the effect of aspect ratio on the seismic response and overturning resistance of a new staggered story isolated structure, three models with different aspect ratios were established. Nonlinear time-history analysis of the three models was conducted using ETABS finite element software. The results indicate that the overturning moment and overturning resistance moment of the superstructure in the new staggered story isolated structure increase with an increasing aspect ratio. However, the increase in the overturning moment of the superstructure is much greater than the increase in the overturning resistance moment, resulting in a decrease in the overturning resistance ratio of the superstructure with an increasing aspect ratio. The overturning moment and overturning resistance moment of the substructure in the new staggered story isolated structure decrease with an increasing aspect ratio. However, the decrease in the overturning moment of the substructure is greater than the decrease in the overturning resistance moment, leading to an increase in the overturning resistance ratio of the substructure with an increasing aspect ratio. The decrease in the overturning resistance ratio of the superstructure in the new staggered story isolated structure is much greater than the increase in the overturning resistance ratio of the substructure. Therefore, as the aspect ratio of the overall structure increases, the overturning resistance ratio of the superstructure and the entire structure decreases. 展开更多
关键词 Aspect Ratio A new Staggered Story Isolated structure Seismic Response Overturning Resistance Ratio Isolated Bearing
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First-Principle Study on the Electronic Structure and Optical Property of New Diluted Magnetic Semiconductor(Y_(0.75)Ca_(0.25))(Cu_(0.75)Mn_(0.25))SO
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作者 Zhou Wenjie 《材料科学与工程(中英文B版)》 2024年第1期14-20,共7页
The band structure,DOSs,and optical properties of(Y_(0.75)Ca_(0.25))(Cu_(0.75)Mn_(0.25))SO,including dielectric function,absorption function,reflection function,and energy loss spectrum were studied by using the first... The band structure,DOSs,and optical properties of(Y_(0.75)Ca_(0.25))(Cu_(0.75)Mn_(0.25))SO,including dielectric function,absorption function,reflection function,and energy loss spectrum were studied by using the first-principles calculation.The calculation results indicate that(Y_(0.75)Ca_(0.25))(Cu_(0.75)Mn_(0.25))SO is a direct bandgap semiconductor with a bandgap of 1.1 eV.The Fermi surface is asymmetric and exhibits spin splitting phenomenon.The new type of dilute magnetic semiconductor(Y_(0.75)Ca_(0.25))(Cu_(0.75)Mn_(0.25))SO exhibits significant light loss around 70 eV,with light reflection gradually increasing after 30 eV,and light absorption mainly occurring around 8-30 eV.These results also provide a basis for the discovery of more types of 1111 phase new dilute magnetic semiconductors in the future. 展开更多
关键词 First-principles calculation electronic structure optical property new diluted magnetic semiconductor
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Density Structure of the Papua New Guinea-Solomon Arc Subduction System
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作者 XU Chong XING Junhui +3 位作者 GONG Wei ZHANG Hao XU Haowei XU Xiaoyu 《Journal of Ocean University of China》 SCIE CAS CSCD 2023年第5期1269-1276,共8页
The Papua New Guinea-Solomon(PN-SL)arc is one of the regions with active crustal motions and strong geological actions.Thus,its complex subduction system makes it an ideal laboratory for studying the initiation mechan... The Papua New Guinea-Solomon(PN-SL)arc is one of the regions with active crustal motions and strong geological actions.Thus,its complex subduction system makes it an ideal laboratory for studying the initiation mechanism of plate subduction.However,the PN-SL subduction system has not yet been sufficiently studied,and its density structure has yet to be revealed.In this paper,we used the free-air gravity data,Parker-Oldenburg density surface inversion method,and the genetic algorithm density inversion method to obtain the density structure of an approximately 1000-km-long northwest-southeast line crossing the PN-SL subduction system under the constraints of the CRUST1.0 global crustal model,onshore seismic data,and the LLNL-G3Dv3 global P-wave velocity model.The density structure shows that density differences between the plates on the two sides of the trench could play a significant role in plate subduction. 展开更多
关键词 Papua new Guinea-Solomon plate subduction gravity anomaly density structure genetic algorithm
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Structure of the Quarks and a New Model of Protons and Neutrons: Answer to Some Open Questions
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作者 Ágnes Cziráki 《Natural Science》 CAS 2023年第1期11-18,共8页
The described structural model tries to answer some open questions such as: Why do quarks not exist in the open state? Where are the antiparticles from the Big Bang?
关键词 structure of Quarks new Model PROTON Neutron Open Questions
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A Glance on the Mineral Deposits and Stratigraphic Sequential Variations and Structures in Different Sections of Indus Basin (Pakistan): New Titanosaurian Sauropod Dinosaurs from the Latest Maastrichtian Vitakri Formation of Pakistan
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作者 Muhammad Sadiq Malkani 《Open Journal of Geology》 2023年第10期1069-1138,共70页
Indus basin hosts many significant mineral deposits like gypsum and cement raw materials, gemstones, iron, coal, marble, dimension and construction stones, petroleum and water resources, world class pink salt and othe... Indus basin hosts many significant mineral deposits like gypsum and cement raw materials, gemstones, iron, coal, marble, dimension and construction stones, petroleum and water resources, world class pink salt and other many minerals in different regions which need further exploitation and development. The construction of new water dams in different regions are vital (for availability of cheap electricity), because of available barren and fertile lands and wastage of water as flood. Further the installation of more cement industries in different regions of Indus Basin especially in middle Indus (Sulaiman Range where gypsum, clays and limestones can be available via belt) can increase export to receive more foreign exchange and make local cement cheap for the sustainable development of Pakistan. 31 stratigraphic sequential sections at different sections of Indus basins are presented to know the variation and local stratigraphy. Further here three new titanosaur taxa are being described. Saraikimasoom is based on snout;Gspsaurus, (Maojandino), Nicksaurus and Khanazeem are based on cranial, vertebral and appendicular elements;Balochisaurus, Marisaurus, Pakisaurus, and 3 new genera and species Imrankhanhero zilefatmi, Qaikshaheen masoomniazi and Ikqaumishan smqureshi based on vertebral and appendicular elements;and Sulaimanisaurus and Khetranisaurus based on only caudal vertebrae. Although Pakistani Titanosaurians seem to be proliferated found from one horizon of Vitakri Formation just below the K-Pg boundary they have a wide range of diagnostic features and key elements among titanosaurs which can be used for comparison and phylogenetic analyses with broad updated character data set of titanosaurs. 展开更多
关键词 Mineral Deposits Stratigraphic Sequences structureS Multiple Sections Indus Super Basin new Titanosaurs Latest Maastrichtian Vitakri Formation Pakistan
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Optimization of Rural Governance Structure under the Development of New Agricultural Management Entities
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作者 Jun Wu Ling Jiang Chaolin Li 《Proceedings of Business and Economic Studies》 2023年第6期55-62,共8页
The positive impact of the development of new agricultural business entities and their institutional systems on the optimization of rural governance structures can be examined from various perspectives,including the s... The positive impact of the development of new agricultural business entities and their institutional systems on the optimization of rural governance structures can be examined from various perspectives,including the state,market,rural society,urban-rural relations,and grassroots governance structure in rural communities.The development of these new agricultural business entities has not only redefined but also restructured the power distribution and governance patterns in rural developing countries,markets,and villages.The rural social order has evolved into a ternary mutual structure governance pattern,often referred to as the“state market rural”model.This transformation has prompted adjustments in the national economic and social policy structure and management systems at both macro and micro levels.It has led to the reshaping of power dynamics,benefit distribution,and governance structures in both urban and rural areas,resulting in significant changes to the economic and social fabric of rural regions.Furthermore,the grassroots governance structure in rural society,characterized by“township governance and village governance,”is undergoing continuous development and improvement.This transition is marked by a shift towards a collaborative governance structure that encourages diverse participation.Building upon the aforementioned optimizations,the rural governance structure now exhibits new characteristics.These include a more extensive and diverse range of rural governance mechanisms,increased openness in governance processes,and a heightened synergy among various governance mechanisms.This dynamic evolution reflects a richer,more diverse,and more open approach to rural governance,fostering a stronger collaborative effort in the pursuit of effective governance. 展开更多
关键词 new agricultural business entities Rural governance structural optimization
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Beijing's Foreign Trade——Readjusting the Structure for New Growth Points in Beijing's Foreign Trade
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作者 Ren Xiaoqiang 《China's Foreign Trade》 1997年第6期16-16,共1页
At a working conference, Vice Mayor Lu Yucheng presented a plan for Beijing’s 1997 work in foreign trade and economic cooperation. The general task is to carry out the strategy of great economy and trade, expand expo... At a working conference, Vice Mayor Lu Yucheng presented a plan for Beijing’s 1997 work in foreign trade and economic cooperation. The general task is to carry out the strategy of great economy and trade, expand exports, use foreign funds reasonably and effectively, and conduct international economic and technical cooperation. The major target is to complete export volume of US$2.3 billion. Last year’s import and 展开更多
关键词 beijing’s Foreign Trade Readjusting the structure for new Growth Points in beijing’s Foreign Trade
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嵌套SP网络的New-Structure系列结构的零相关线性逼近与不可能差分性质研究 被引量:3
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作者 付立仕 崔霆 金晨辉 《电子学报》 EI CAS CSCD 北大核心 2017年第6期1367-1374,共8页
分组密码的安全性分析是密码学的重要研究内容,其中不可能差分分析和零相关线性分析是密码算法安全性分析的重要方法.本文利用中间相错方法,通过对扩散层进行限制,给出了嵌套SP网络的New-Structure系列结构的零相关线性逼近.给出了New-S... 分组密码的安全性分析是密码学的重要研究内容,其中不可能差分分析和零相关线性分析是密码算法安全性分析的重要方法.本文利用中间相错方法,通过对扩散层进行限制,给出了嵌套SP网络的New-Structure系列结构的零相关线性逼近.给出了New-Structure I和New-Structure IV结构中概率非零的差分传递链和相关优势非零的线性逼近传递链在结构上的一致性.此外也给出了嵌套SP网络New-Structure I、III的16/22轮不可能差分特征.最后给出在分组规模和密钥规模均为128比特时,对New-Structure I,III,IV进行21/28/22轮的不可能差分攻击和19/28/22轮的多维零相关线性逼近攻击所需要的时间复杂度和数据复杂度.本文的结果对基于New-Structure结构设计的密码算法的安全性分析提供了理论依据. 展开更多
关键词 信息安全 不可能差分分析 零相关线性分析 new-structure系列
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Dynamic behavior of new cutting subgrade structure of expensive soil under train loads coupling with service environment 被引量:16
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作者 QIU Ming-ming YANG Guo-lin +3 位作者 SHEN Quan YANG Xiao WANG Gang LIN Yu-liang 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第4期875-890,共16页
Expansive soil is sensitive to dry and wet environment change. And the volume deformation and inflation pressure of expansive soil may induce to cause the deformation failure of roadbed or many other adverse effects. ... Expansive soil is sensitive to dry and wet environment change. And the volume deformation and inflation pressure of expansive soil may induce to cause the deformation failure of roadbed or many other adverse effects. Aimed at a high-speed railway engineering practice in the newly built Yun-Gui high-speed railway expansive soil section in China, indoor vibration test on a full-scaled new cutting subgrade model is carried out. Based on the established track-subgrade-foundation of expansive soil system dynamic model test platform, dynamic behavior of new cutting subgrade structure under train loads coupling with extreme service environment(dry, raining, and groundwater level rising) is analyzed comparatively. The results show that the subgrade dynamic response is significantly influenced by service conditions and the dynamic response of subgrade gradually becomes stable with the increasing vibration times under various service environment conditions. The vertical dynamic soil stress is related with the depth in an approximate exponential function, and the curves of vertical dynamic soil stress present a "Z" shape distribution along transverse distance. The peak value of dynamic soil stress appears below the rail, and it increases more obviously near the roadbed surface. However, the peak value of dynamic soil stress is little affected outside 5.0 m of center line. The vibration velocity and acceleration are in a quadratic curve with an increase in depth, and the raining and groundwater level rising increase both the vibration velocity and the acceleration. The vertical deformations at different depths are differently affected by service environment in roadbed. The deformation of roadbed increases sharply when the water gets in the foundation of expansive soil, and more than 60% of the total deformation of roadbed occurs in expansive soil foundation. The laid waterproofing and drainage structure layer, which weakens the dynamic stress and improves the track regularity, presents a positive effect on the control deformation of roadbed surface. An improved empirical formula is then proposed to predict the dynamic stress of ballasted tracks subgrade of expansive soil. 展开更多
关键词 high-speed RAILWAY FULL-SCALE model testing dynamic response expansive SOIL service environment new SUBGRADE structure
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Human Capital Structure and Economic Growth:From the Perspective of New Structural Economics 被引量:9
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作者 Feng Jun Li Mingfeng 《China Economist》 2019年第6期36-55,共20页
The Chinese economy has achieved remarkable development over the past 40 years of reform and opening-up.However,with the narrowing of potential for efficiency improvement from resources reallocation and changes in pop... The Chinese economy has achieved remarkable development over the past 40 years of reform and opening-up.However,with the narrowing of potential for efficiency improvement from resources reallocation and changes in population age structure,the Chinese economy has moved from high-speed growth to high-quality development.In this setting,understanding factor endowment and comparative advantages of the economy from a perspective of human capital structure so as to enhance industrial structure adaptability by riding the trend is of significance for cultivating new driving force for economic development.This paper,following a theoretical paradigm of new structural economics,demonstrates how human capital structure matches industrial structure and the presence of optimal human capital structure using mathematical deduction.On this basis,national level panel data and instrumental variables are adopted for generalized method of moments,the results of which shows that there are varied impacts on economic growth in light of different human capital structure characteristics.The proportions of high-level human capital and medium-level human capital boost economic development,while that of low-level human capital has an inhibitory effect on economic growth.The policy implication of this study is that large economies should diversify efforts as per different human capital structure characteristics in terms of development need of tapping growth impetus from human capital structure improvement.It is of equal importance to raise the proportion of high and medium human capital in order to stimulate economic growth and to cut the proportion of low human capital that hinders economic development. 展开更多
关键词 human CAPITAL structure ECONOMIC growth new structurAL ECONOMICS
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Exotic Localized Coherent Structures of New (2+1)-Dimensional Soliton Equation 被引量:8
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作者 ZHANG Jie-Fang HUANG Wen-Hua ZHENG Chun-Long 《Communications in Theoretical Physics》 SCIE CAS CSCD 2002年第11期517-522,共6页
The variable separation approach is used to obtain localized coherent structures of the new (2+1)-dimensional nonlinear partialdifferential equation. Applying the Backlund transformation and introducing the arbitraryf... The variable separation approach is used to obtain localized coherent structures of the new (2+1)-dimensional nonlinear partialdifferential equation. Applying the Backlund transformation and introducing the arbitraryfunctions of the seed solutions, the abundance of the localized structures of this model are derived. Some special types ofsolutions solitoff, dromions, dromion lattice, breathers and instantons are discussed by selecting the arbitrary functionsappropriately. The breathers may breath in their amplititudes, shapes, distances among the peaks and even the numberof the peaks. 展开更多
关键词 variable separation approach coherent structures new (2+1)-dimensional SOLITON equation
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THE STRUCTURE OF ARMILLARIZIN,A NEW PROTOILLUDANE SESQUITERPENOID AROMATIC ESTER FROM ARMILLARIA MELLEA(VAHL.EX FR)QUEL. 被引量:8
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作者 Jun Shan YANG Ya Lun SU Yu Lan WANG Xiao Zhang FENG De Quan YU Xiao Tian LIANG Institute of Materia Medica,Chinese Academy of Medical Sciences,Beijing,100050 《Chinese Chemical Letters》 SCIE CAS CSCD 1990年第2期173-174,共2页
A new protoilludane sesquiterpenoid aromatic ester,named armillarizin (1)has been isolated from the artificially cultured mycelium of Armillaria me- llea(Vahl.ex Fr)Quel.(Tricholomataceae).Its structure was deduced on... A new protoilludane sesquiterpenoid aromatic ester,named armillarizin (1)has been isolated from the artificially cultured mycelium of Armillaria me- llea(Vahl.ex Fr)Quel.(Tricholomataceae).Its structure was deduced on the ba- sis of spectral analyses.The relative configuration was established from the nuclear Overhauser effects and from the values of ~1H-~1H coupling constants. 展开更多
关键词 FR THE structure OF ARMILLARIZIN A new PROTOILLUDANE SESQUITERPENOID AROMATIC ESTER FROM ARMILLARIA MELLEA VAHL.EX FR)QUEL
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Translocator protein 18 kDa(TSPO): old dogma, new mice, new structure, and new questions for neuroprotection 被引量:1
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作者 Eun-Jung Kim Seong-Woon Yu 《Neural Regeneration Research》 SCIE CAS CSCD 2015年第6期878-880,共3页
The normal development and optimal functioning of the brain requires a vigilant immune surveillance system to detect and remove potential risk factors and prevent infection and tissue damage. Microglia are the residen... The normal development and optimal functioning of the brain requires a vigilant immune surveillance system to detect and remove potential risk factors and prevent infection and tissue damage. Microglia are the resident immune cells and the frontline defenders responsible for the immune response of the brain. Resting microglia possess a ramified morphology with numerous thin processes that continuously sample the environment. In response to inflammatory signals, microglia become activated and transform their morphology into a thick, amoeboid-like shape. Activated microglia proliferate, tolerate to sites of iniurv, 展开更多
关键词 TSPO old dogma Translocator protein 18 kDa new mice new structure
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SYNTHESIS AND CRYSTAL STRUCTURE OF A NEW COMPOUND Sr_6Sn_2Nb_8O_30 被引量:1
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作者 FANG Liang ZHANG Hui WU Bolin YUAN Runzhang Wuhan University of Technology 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 1999年第2期35-39,共5页
A new compound Sr6Sn2Nb8O30 was found in the ternary system of SrO-SnO2-Nb2O5. The transparent colorless crystal with needle-like shape can be grown by flux method. The crystal structure of new compound was determined... A new compound Sr6Sn2Nb8O30 was found in the ternary system of SrO-SnO2-Nb2O5. The transparent colorless crystal with needle-like shape can be grown by flux method. The crystal structure of new compound was determined by X-ray diffraction, and its belongs to tungsten bronze structure. Sr6Sn2Nb8O30 crystallizes in orthorhombic system with unit cell parameters a= 17. 579 (DA,6= 17. 509(DA,c=7. 7880(5)A,Z = 4 and space group Cmm2. 展开更多
关键词 Sr_6Sn_2Nb_8O_30 system new compound tungsten bronze structure
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ISOLATION, STRUCTURE ELUCIDATION AND SYNTHESIS OF A NEW PRENYLATED FLAVONOL, MAACKIAFLAVONOL, FROM MAACKIA TENUIFOLIA 被引量:2
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作者 Jian Hua SHEN, Lan WANG and Bing Nan ZHOU State Key Laboratory for New Drug Research, Shanghai Institute of Materia Medica, Academia Sinica, Shanghai 200031 《Chinese Chemical Letters》 SCIE CAS CSCD 1991年第8期629-630,共2页
A new prenylated flavonol, maackiaflavonol, was isolated from the ethanol extract of the roots of Maackia tenuifolia. Its structure was elucidated as 7-hydrox-8-prenylflavonol by means of spectroscopic analysis (UV, I... A new prenylated flavonol, maackiaflavonol, was isolated from the ethanol extract of the roots of Maackia tenuifolia. Its structure was elucidated as 7-hydrox-8-prenylflavonol by means of spectroscopic analysis (UV, IR, MS, NMR and 1H-1H COSY) and confirmed by total synthesis. 展开更多
关键词 ISOLATION MAACKIAFLAVONOL structure ELUCIDATION AND SYNTHESIS OF A new PRENYLATED FLAVONOL FROM MAACKIA TENUIFOLIA
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Exotic Localized Coherent Structures of New(2+1)-Dimensional Soliton Equation 被引量:2
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作者 ZHANGJie-Fang HUANGWen-Hua 《Communications in Theoretical Physics》 SCIE CAS CSCD 2002年第5期517-522,共6页
The variable separation approach is used to obtain localized coherent structures of the new (2+1)-dimensional nonlinear partial differential equation. Applying the B?cklund transformation and introducing the arbitrary... The variable separation approach is used to obtain localized coherent structures of the new (2+1)-dimensional nonlinear partial differential equation. Applying the B?cklund transformation and introducing the arbitrary functions of the seed solutions, the abundance of the localized structures of this model are derived. Some special types of solutions solitoff, dromions, dromion lattice, breathers and instantons are discussed by selecting the arbitrary functions appropriately. The breathers may breath in their amplititudes, shapes, distances among the peaks and even the number of the peaks. 展开更多
关键词 variable separation approach coherent structures new (2+1)-dimensional soliton equation
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Atomically self-healing of structural defects in monolayer WSe_(2)
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作者 Kangshu Li Junxian Li +2 位作者 Xiaocang Han Wu Zhou Xiaoxu Zhao 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第9期49-55,共7页
Minimizing disorder and defects is crucial for realizing the full potential of two-dimensional transition metal dichalcogenides(TMDs) materials and improving device performance to desired properties. However, the meth... Minimizing disorder and defects is crucial for realizing the full potential of two-dimensional transition metal dichalcogenides(TMDs) materials and improving device performance to desired properties. However, the methods in defect controlcurrently face challenges with overly large operational areas and a lack of precision in targeting specific defects. Therefore,we propose a new method for the precise and universal defect healing of TMD materials, integrating real-time imaging withscanning transmission electron microscopy (STEM). This method employs electron beam irradiation to stimulate the diffusionmigration of surface-adsorbed adatoms on TMD materials grown by low-temperature molecular beam epitaxy (MBE),and heal defects within the diffusion range. This approach covers defect repairs ranging from zero-dimensional vacancydefects to two-dimensional grain orientation alignment, demonstrating its universality in terms of the types of samples anddefects. These findings offer insights into the use of atomic-level focused electron beams at appropriate voltages in STEMfor defect healing, providing valuable experience for achieving atomic-level precise fabrication of TMD materials. 展开更多
关键词 scanning transmission electron microscopy(STEM) atom manipulation nanoscale materials and structures:fabrication and characterization new materials:theory design FABRICATION
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An Analysis of the Consumer Demand Structure of Rural Residents in Chongqing City in the Context of New Urbanization
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作者 Xiaomin JIA 《Asian Agricultural Research》 2015年第7期30-32,共3页
Using ELES model and econometric methods,in the context of new urbanization,we use the time series data on the consumer spending of rural residents in Chongqing City to perform an empirical analysis of the consumer de... Using ELES model and econometric methods,in the context of new urbanization,we use the time series data on the consumer spending of rural residents in Chongqing City to perform an empirical analysis of the consumer demand structure of rural residents,reveal the characteristics,differences and changes concerning the consumption structure of rural residents in Chongqing City,and set forth some policy recommendations such as carrying out the new rural construction,optimizing the consumption structure,establishing sound social security system and income growth mechanism,and stabilizing the price level. 展开更多
关键词 new URBANIZATION CONSUMPTION structure of RURAL RE
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Synthetic Human Embryo-Like Structure: A New Paradigm for Human Embryology
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作者 Jianping Fu 《医用生物力学》 EI CAS CSCD 北大核心 2019年第A01期25-26,共2页
Early human embryonic development remains mysterious due to drastic species divergences between humans and othermammalian models and limited accessibility to human embryo samples. Recent studies from my laboratory and... Early human embryonic development remains mysterious due to drastic species divergences between humans and othermammalian models and limited accessibility to human embryo samples. Recent studies from my laboratory and others haveshown that under suitable culture conditions human pluripotent stem cells ( hPSCs) can undergo intricate morphogenetic eventsand self-organize to form patterned human embryo-like structures in vitro. These synthetic human embryonic tissueshold great promises for advancing human embryology and reproductive medicine. In this talk,I will describe a hPSC-based,synthetic 3D model of human post-implantation development that recapitulates key developmental landmarks successively,including pro-amniotic cavity formation,amniotic ectoderm-epiblast patterning,primordial germ cell specification,and developmentof the primitive streak with controlled anteroposterior polarity ( Fig.1) . We further show that the amniotic ectoderm,as the first lineage that segregates from the epiblast upon implantation of the human embryo,functions as a signaling centerto trigger primitive streak development in the epiblast. Together,our research has developed a powerful synthetic embryologicalmodel and provided new understandings of previously inaccessible but critical embryogenic events in human development. 展开更多
关键词 A new PARADIGM for HUMAN EMBRYOLOGY SYNTHETIC HUMAN Embryo-Like structure
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CRYSTAL STRUCTURE OF THE COPPER(II) COMPLEX OF NEW MACROCYCLIC DIOXOTETRAAMINE LIGAND FUNCTIONALIZED WITH 8-METHYL QUINOLINE PENDANT
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作者 Xian He BU Dao Li AN Man Xue YUAN and Yun Ti CHEN (Department of Chemistry, Nankai University,Tianjin 300071) 《Chinese Chemical Letters》 SCIE CAS CSCD 1994年第12期1055-1056,共2页
The copper (II) complex (1) of a new Iigand 4- (quinolin-8-ylmethyl)- 1, 4, 7. 10-tetraazacycoltridecane-11. 13-dione (L) has been syntehsized and its crystal structure determined. It is of orthorhomic crystal system ... The copper (II) complex (1) of a new Iigand 4- (quinolin-8-ylmethyl)- 1, 4, 7. 10-tetraazacycoltridecane-11. 13-dione (L) has been syntehsized and its crystal structure determined. It is of orthorhomic crystal system and Pcad space group with a=16.260 (3), b=7. 739 (2). c=27. 530 (9) A, Mr=416. 97, Z=8. Dx=1. 595 g/cm3,μ=12. 876 cm-1, and F(000)=1736. The final R factor is 0. 061 for 2594 observed reflections with I>3σ(I). The Cu .atom is five coordinated to form a distorted square pyramid geometry in which N(11) of the pendant is at apical site. 展开更多
关键词 II THE OF new structure COMPLEX COPPER
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