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Possibility of Searching for Accreting White Dwarfs with the Chinese Space Station Telescope

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Research in Astronomy and Astrophysics 2022年第5期22卷 21-27页

作者： wei xie Hai-Liang Chen Yunnan Observatories Chinese Academy of SciencesKunming 650216China University of the Chinese Academy of Sciences Beijing 100049China

Accreting WDs are very important for the studies of binary evolution,binary population synthesis and accretion *** far,there are a lot of accreting WD binaries with low accretion rates,such as cataclysmic variables,detected by different ***,few accreting WD binaries with high accretion rates have been *** this paper,we studied the spectrum properties of accreting WD binaries and investigated whether accreting WD binaries with high accretion rates can be detected by the Chinese Space Station Telescope(CSST).We found that some accreting WD binaries with high accretion rates can be distinguishable from other types of stars with(NUV-y,u-y),(NUV-r,u-g),(NUV-i,u-g),(NUV-z,u-g)and(NUV-y,u-g)color-color ***,some accreting WD binaries with high accretion rates can be detected by the CSST.

关键词： white dwarf stars whitedwarfs-binarystars close binarystars-low massstars low-massstar

The prospects for China＇＇s food security and imports： Will China starve the world via imports？

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Journal of Integrative Agriculture 2017年第12期16卷 2933-2944页

作者： HUANG Ji-kun wei wei CUI Qi xie wei China Center for Agricultural Policy School of Advanced Agricultural Sciences Peking University Beijing 100871 P.R. China Center for Chinese Agricultural Policy Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 P.R.China University of Chinese Academy of Sciences Beijing 100049 P.R.China

China＇s food supply and demand have significant implications for both China＇s own national food security and that of the world. This study reviews China＇s food security prospects and their implications, focusing on international trade in the coming decade. The results show that China＇s policies for ensuring food security will be enhanced and China will move to sustainable agriculture. Most studies anticipate that China will increase its food and feed imports in the coming decade. China＇s overall food self-sufficiency is likely to fall from 94.5% in 2015 to around 91% by 2025. The greatest increases in imports are likely to be soybean, maize, sugar, and dairy products. However, within the production capacity of the major exporting countries and of many food-importing developing countries, China＇s additional imports of 3 to 5% of its total food consumption in the coming decade are unlikely to threaten global food security. Indeed, the projected imports of feed and several foods could provide opportunities for many exporting countries to expand their production and save global resources.

关键词： food security food supply import China global

Cell adhesion molecules in Drosophila synapse development and function

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Science China(Life Sciences) 2012年第1期55卷 20-26页

作者： SUN MingKuan xie wei Key Laboratory of DGHD MOEInstitute of Life SciencesSoutheast UniversityNanjing 210096China

Synapse is a highly specialized inter-cellular structure between neurons or between a neuron and its target cell that mediates cell-cell communications. Ample results indicate that synaptic adhesion molecules are critically important in modulating the complexity and specificity of the synapse. And disruption of adhesive properties of synapses may lead to neurodevelopmental or neurodegenerative diseases. In this review, we will use the Drosophila NMJ as a model system for glutamatergic synapses to discuss the structure and function of homophilic and heterophilic synaptic adhesion molecules with special focus on recent findings in neurexins and neuroligins in Drosophila.

关键词： Drosophila cell adhesion molecules synapse neuromuscular junction neurexin neuroligin

Regularized inversion for coseismic slip distribution with active constraint balancing

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Journal of Central South University 2017年第12期24卷 2961-2968页

作者： TONG Xiao-zhong xie wei GAO Da-wei School of Geosciences and Info-physics Central South University School of Earth and Ocean Sciences University of Victoria

Estimating the spatial distribution of coseismic slip is an ill-posed inverse problem, and solutions may be extremely oscillatory due to measurement errors without any constraints on the coseismic slip distribution. In order to obtain stable solution for coseismic slip inversion, regularization method with smoothness-constrained was imposed. Trade-off parameter in regularized inversion, which balances the minimization of the data misfit and model roughness, should be a critical procedure to achieve both resolution and stability. Then, the active constraint balancing approach is adopted, in which the trade-off parameter is regarded as a spatial variable at each model parameter and automatically determined via the model resolution matrix and the spread function. Numerical experiments for a synthetical model indicate that regularized inversion using active constraint balancing approach can provides stable inversion results and have low sensitivity to the knowledge of the exact character of the Gaussian noise. Regularized inversion combined with active constraint balancing approach is conducted on the 2005 Nias earthquake. The released moment based on the estimated coseismic slip distribution is 9.91×1021 N·m, which is equivalent to a moment magnitude of 8.6 and almost identical to the value determined by USGS. The inversion results for synthetic coseismic uniform-slip model and the 2005 earthquake show that smoothness-constrained regularized inversion method combined with active constraint balancing approach is effective, and can be reasonable to reconstruct coseismic slip distribution on fault.

关键词： coseismic slip inversion trade-off parameter active constraint balancing model resolution matrix spread function

Changes of Population, Built-up Land, and Cropland Exposure to Natural Hazards in China from 1995 to 2015

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International Journal of Disaster Risk Science 2019年第4期10卷 557-572页

作者： Yimin Chen wei xie Xiaocong Xu School of Geography and Planning Sun Yat-sen UniversityGuangzhou 510275China Guangdong Key Laboratory for Urbanization and Geosimulation Sun Yat-sen UniversityGuangzhou 510275China

By using the latest China population grid and land-use data,we assess the changing exposure of China’s population and land uses to the hazards of storm surges,droughts,earthquakes,floods,and landslides from 1995 *** found that the single-hazard areas and the multihazard areas covered 43%and 26%of China’s territory,*** grew faster in the hazard-prone areas than in the non-hazard ***-up area expanded more rapidly in the areas prone to earthquakes and *** changed rapidly in many hazard-prone *** hazard-prone areas affected by floods featured the highest cropland loss rates,while the areas prone to earthquakes and landslides featured the highest cropland growth *** detected areas with significant exposure changes by using hot spot *** was found that population and built-up land in the Pearl River Basin were increasingly exposed to storm surges,floods,and *** Haihe River Basin and Huaihe River Basin also showed a consistent increase of population and built-up land exposure to droughts and *** findings can provide a foundation for the design and implementation of protection and adaptation strategies to improve the resilience of Chinese society to natural hazards.

关键词： China Exposure to natural hazards Population change Built-up land Cropland

Te-Pei Feng:a pioneer of neuromuscular physiology in China

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Protein & Cell 2022年第6期13卷 387-393页

作者： wei xie Ben-Yu Guo Yanyan Qian School of Psychology Nanjing Normal UniversityNanjing210097China Social and Behavioral Sciences Faculty Leiden University2333ACLeidenThe Netherlands

Te-Pei Feng(冯德培,1907–1995),was a famous Chinese neurophysiologist and also one of the pioneers of modern physiological researches in China(Fig.1).He mainly studied chemical transmission at the neuromuscular junction,the biological characteristic of high and low contraction speed muscles,and the long-term potentiation(LTP)function of the brain(Jin,2007).Richard Wuyin Tsien(钱永佑)of Stanford University highly valued Feng’s contributions to neurology in China,stating that,“It is safe to say that the past and the future of neuroscience in China would be very different had professor Feng not provided leadership,by dint of organization,persuasion and strong personal ***,Feng’s remarkable life and career spanned a lengthy epoch of history,in both the world and scientific arenas。

关键词： epoch contraction pioneer

Optimal design of a multi-mode interference splitter based on SOI

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Optoelectronics Letters 2008年第2期4卷 92-95页

作者： SONG wei xie Kang School of Optoelectronic Information University of Electronic Science and Technology of China Chengdu 610054 China

In this paper, the multimode waveguide lengths and the output port locations of a SOI （silicon on insulator） material-based 1×4 MMI （multimode interference） optical splitter are optimized by means of FD-BPM （finite difference - beam propagation method）. An improved 1×4 MMI optical splitter is designed. Compared with an usual optical splitter, a smaller loss 0. 12dB and a better output port power uniformity 0.11dB are achieved for the optical signal transmission.

关键词：多模式干涉分路器最优设计 SOI 透射

PERFORMANCE-BASED INTELLIGENT RESOURCE DESCRIPTION MODEL FOR INTERNET-BASED PRODUCT DESIGN

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Chinese Journal of Mechanical Engineering 2006年第1期19卷 96-100页

作者： ZHU Aibin CHEN wei xie Youbai Key Laboratory of Education Ministry for Mordern Design and Rotor-Searing System Xi＇ an Jiaotong University Xi＇ an 710049 China

Issues on intelligent resource description and multiple intelligent resources integration for lntemet based collaborative design are analyzed. A performance-based intelligent resource description model for lnternet-based product design is proposed, which can help to create, store, manipulate and exchange intelligent resource description information for applications, tools and systems in Interact-based product design. A method to integrate multiple intelligent resources to fulfill a complex product design and analysis via lntemet is also proposed. A real project for improving the bearing system design of a turbo-expander with many intelligent resources in prominent universities is presented as a case study.

关键词： Collaborative design Intelligent resource Performance feature Knowledge acquirement

EFFECT OF Mg AND δ-PHASE ON MECHANICAL PROPERTIES OF ALLOY GH169(INCONEL718)

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Acta Metallurgica Sinica(English Letters) 1993年第6期6卷 405-409页

作者： DONG Jianxin xie wei XU Zhichao xie Xishan ZHANG Shouhua University of Science and Technology Beijing BeijingChina

Micro-alloying of Mg,ranged from 30 to 70 ppm,may improve the high temperature ductility,stress rupture,especially,certain important mechanical properties,such as cyclic stress rupture,creep/fatigue interaction and crack propagation *** quantity, morphology and distribution of δ-phase may obviously influence the notched cyclic stress rup- ture *** relevant microstructure shows that the Mg may also influence to certain extent on the feature of δ-***,to keep the Mg and δ-phase under control may further im- prove the mechanical properties of alloy GH169.

关键词： superalloy GH169 mechanical property δ-phase Mg creep/fatigue interaction craek propagation rate