|
|
|
题名
|
作者
|
年代
|
出处
|
被引量
|
| 1 | A semi-spring and semi-edge combined contact model in CDEM and its application to analysis of Jiweishan landslide显示文摘Continuum-based discrete element method(CDEM)is an explicit numerical method used for simulation of progressive failure of geological body.To improve the efficiency of contact detection and simplify the calculation steps for contact forces,semi-spring and semi-edge are introduced in calculation.Semispring is derived from block vertex,and formed by indenting the block vertex into each face(24semisprings for a hexahedral element).The formation process of semi-edge is the same as that of semi-spring(24semi-edges for a hexahedral element).Based on the semi-springs and semi-edges,a new type of combined contact model is presented.According to this model,six contact types could be reduced to two,i.e.the semi-spring target face contact and semi-edge target edge contact.By the combined model,the contact force could be calculated directly(the information of contact type is not necessary),and the failure judgment could be executed in a straightforward way(each semi-spring and semi-edge own their characteristic areas).The algorithm has been successfully programmed in C++program.Some simple numerical cases are presented to show the validity and accuracy of this model.Finally,the failure mode,sliding distance and critical friction angle of Jiweishan landslide are studied with the combined model. | Chun Feng Shihai Li Xiaoyu Liu Yanan Zhang | 2014 | Journal of Rock Mechanics and Geotechnical Engineering2014，6，1： | 34 |
| 2 | A fundamental theorem for eco-environmental surface modelling and its applications显示文摘We propose a fundamental theorem for eco-environmental surface modelling(FTEEM) in order to apply it into the fields of ecology and environmental science more easily after the fundamental theorem for Earth’s surface system modeling(FTESM). The Beijing-Tianjin-Hebei(BTH) region is taken as a case area to conduct empirical studies of algorithms for spatial upscaling, spatial downscaling, spatial interpolation, data fusion and model-data assimilation, which are based on high accuracy surface modelling(HASM), corresponding with corollaries of FTEEM. The case studies demonstrate how eco-environmental surface modelling is substantially improved when both extrinsic and intrinsic information are used along with an appropriate method of HASM. Compared with classic algorithms, the HASM-based algorithm for spatial upscaling reduced the root-meansquare error of the BTH elevation surface by 9 m. The HASM-based algorithm for spatial downscaling reduced the relative error of future scenarios of annual mean temperature by 16%. The HASM-based algorithm for spatial interpolation reduced the relative error of change trend of annual mean precipitation by 0.2%. The HASM-based algorithm for data fusion reduced the relative error of change trend of annual mean temperature by 70%. The HASM-based algorithm for model-data assimilation reduced the relative error of carbon stocks by 40%. We propose five theoretical challenges and three application problems of HASM that need to be addressed to improve FTEEM. | Tianxiang YUE Na ZHAO Yu LIU Yifu WANG Bin ZHANG Zhengping DU Zemeng FAN Wenjiao SHI Chuanfa CHEN Mingwei ZHAO Dunjiang SONG Shihai WANG Yinjun SONG Changqing YAN Qiquan LI Xiaofang SUN Lili ZHANG Yongzhong TIAN Wei WANG Ying’an WANG Shengnan MA Hongsheng HUANG Yimin LU Qing WANG Chenliang WANG Yuzhu WANG Ming LU Wei ZHOU Yi LIU Xiaozhe YIN Zong WANG Zhengyi BAO Miaomiao ZHAO Yapeng ZHAO Yimeng JIAO Ufra NASEER Bin FAN Saibo LI Yang YANG John PWILSON | 2020 | Science China Earth Sciences2020，63，8： | 7 |
| 3 | Optical observations of LIGO source GW 170817 by the Antarctic Survey Telescopes at Dome A,Antarctica显示文摘The LIGO detection of gravitational waves(GW) from merging black holes in 2015 marked the beginning of a new era in observational astronomy. The detection of an electromagnetic signal from a GW source is the critical next step to explore in detail the physics involved. The Antarctic Survey Telescopes(AST3),located at Dome A, Antarctica, is uniquely situated for rapid response time-domain astronomy with its continuous night-time coverage during the austral winter. We report optical observations of the GW source(GW 170817) in the nearby galaxy NGC 4993 using AST3. The data show a rapidly fading transient at around 1 day after the GW trigger, with the i-band magnitude declining from 17:23 ± 0:13 magnitude to 17:72 ± 0:09 magnitude in ~1:8 h. The brightness and time evolution of the optical transient associated with GW 170817 are broadly consistent with the predictions of models involving merging binary neutron stars. We infer from our data that the merging process ejected about ~10^(-2) solar mass of radioactive material at a speed of up to 30% the speed of light. | lei hu xuefeng wu igor andreoni michael c.b.ashley jeff cooke xiangqun cui fujia du zigao dai bozhong gu yi hu haiping lu xiaoyan li zhengyang li ensi liang liangduan liu bin ma zhaohui shang tianrui sun n.b.suntzeff charling tao syed a.uddin lifan wang xiaofeng wang haikun wen di xiao jin xu ji yang shihai yang xiangyan yuan hongyan zhou hui zhang jilin zhou zonghong zhu | 2017 | Science Bulletin2017，62，21： | 6 |
| 4 | A two-scale contact model for collisions between blocks in CDEM显示文摘Contact detection between interacting blocks is of great importance to discontinuity-based numerical methods, such as DDA, DEM, and NMM. A rigorous contact theory is a prerequisite to describing the interactions of multiple blocks. Currently, the penalty method, in which mathematical springs with high stiffness values are employed, is always used to calculate the contact forces. High stiffness values may cause numerical oscillations and limit the time step. Furthermore, their values are difficult to identify. The intention of this study is to present a two-scale contact model for the calculation of forces between colliding blocks. In this new model, a calculation step taken from the moment of contact will be divided into two time stages: the free motion time stage and the contact time stage. Actually, these two time stages correspond to two real physical processes. Based on this, we present a new numerical model that is intended to be more precise and useful in calculating the contact forces without mathematical springs. The propagation of the elastic wave during collision is of a characteristic length, which determines the volume of material involved in the contact force calculation. In conventional contact models, this range is always regarded as the length of one element, which may lead to an inaccurate calculation of contact forces. In fact, the real scale of this range is smaller than the length of a single element, and subdivided elements, which are refined according to the characteristic length and are presented in the new contact model. | LI ShiHai TANG DeHong WANG Jie | 2015 | Science China(Technological Sciences)2015，58，9： | 4 |
| 5 | Nutritional strategies to alleviate oxidative stress in sows显示文摘The performance of high-yielding sows is directly related to the productivity of pig farming. Fetaldevelopment mainly occurs during the last month of pregnancy, and the aggressive metabolic burden ofsows during this stage eventually leads to systemic oxidative stress. When affected by oxidative stress,sows exhibit adverse symptoms such as reduced feed intake, hindered fetal development, and evenabortion. In addition, milk synthesis during the lactation period causes a severe metabolic burden. Thebiological response to oxidative stress during this period is associated with a decrease in milk production,which further affects the growth of piglets. Understanding the nutritional strategies to alleviateoxidative stress in sows is crucial to maintain their reproduction and lactation performance. Recently,advances have been made in the field of nutrition to relieve oxidative stress in sows during late pregnancyand lactation. This review highlights the nutritional strategies to relieve oxidative stress in sowsreported within the last 20 years. | Qihui Li Siwang Yang Fang Chen Wutai Guan Shihai Zhang | 2022 | Animal Nutrition2022，，2： | 4 |
| 6 | Martensitic Transformation and Magnetic-Field-Induced Strain in Magnetic Shape Memory Alloy NiMnGa Melt-Spun Ribbon显示文摘A magnetic shape memory alloy with nonstoichiometric Ni5oMn27Ga23 was prepared by using melt-spinning technology. The martensitic transformation and the magnetic-field-induced strain (MFIS) of the polycrystalline melt-spun ribbon were investigated. The experimental results showed that the melt-spun ribbons underwent thermal-elastic martensitic transformation and reverse transformation in cooling and heating process and exhibited typical thermoelastic shape memory effect. However the start temperature for martensitic transformation decreased from 286 K for as-cast alloy to 254 K for as-quenched ribbon and Curie temperature remains approximately constant. A particular internal stress induced by melt-spinning resulted in the formation of a texture structure in the ribbons, which made the ribbons obtain larger martensitic transformation strain and MFIS. The internal stress was released substantially after annealing, which resulted in a decrease of MFIS of the ribbons. | Shihai GUO, Yanghuan ZHANG, Jianliang LI, Baiyun QUAN, Yan QI and Xinlin WANG Department of Functional Material Research, Central Iron and Steel Research Institute, Beijing 100081, China | 2005 | Journal of Materials Science & Technology2005，21，2： | 3 |
| 7 | Structure and Corrosion Resistance of Microarc Oxidation Coatings on AZ91D Magnesium Alloy显示文摘Magnesium alloys are widely used as shells of 3C (computer, mobile phone and consumer electronics) equipments for its impressive mechanical and physical properties, such as low density, good resistance to electromagnetic radiation, suitable for high pressure diecasting and easily recycling, etc. But poor corrosion resistance confines its extensively application. In this paper, protective coatings was successfully prepared on AZ91D magnesium alloys by micro-arc oxidation (MAO) and painting process. Microstructures and phases of MAO coatings were invesgated with scanning electron microscope (SEM) and X-Ray diffractometer. Mechanical properties of MAO coating, such as adhesive force and corrosion resistance, were also tested. Results showed that MAO coatings were a good base for painting process. MAO coatings with paint have good adhesive properties to base metal and excellent corrosion resistance. Micro-arc oxidation with painting process is a good kind of surface treatment to improve the corrosion resistance of mobile phone shell made of AZ91D magnesium alloys. | Cui Shihai Han Jianmin Li Weijing Li Ronghua Zhu Xiaowen Wang Jinhua | 2004 | Journal of Rare Earths2004，22，z2： | 3 |
| 8 | mRNA profiles of cytokine receptors in unstimulated peripheral blood mononuclear cells from patients with chronic idiopathic urticaria显示文摘This present study was aimed to investigate the roles of the receptors of Th1/Th2 cytokines and chemokines in the pathogenesis of chronic idiopathic urticaria (CIU).Thirty patients with CIU,30 patients with dermographism and 30 healthy controls were randomly enrolled.Reverse transcription-PCR (RT-PCR) was used to analyze the mRNA of cytokine receptors in peripheral blood mononuclear cells (PBMCs).The mRNA levels of tumor necrosis factor receptor (TNFR),interferon-γ receptor (IFN-γR),and interleukin-10 receptor (IL-10R) were statistically increased in the CIU group (P < 0.05),while IL-2R,IL-4R,IL-6R,and IL-13R showed no significant differences between the CIU and other groups.The mRNA levels of CCR3 and CCR6 were statistically increased in the CIU group (P < 0.05).The toll-like receptor 2 (TLR2) mRNA level was significantly lower in the CIU group than the healthy control group (P < 0.05).These findings indicate that the regulation of mRNA of TNFR,IFN-γR,IL-10R,CCR3,CCR6 and TLR2 may be involved in the pathogenesis of CIU. | Jianming Gao Aizhen Yang Min Chen Ansheng Li Xu Yao Yumei Li Shihai Xie Xueyuan Yang Liansheng Zhong Zhiqiang Chen | 2011 | The Journal of Biomedical Research2011，25，2： | 3 |
| 9 | IL-9 blockade attenuates inflammation in a murine model of methicillin-resistant Staphylococcus aureus pneumonia显示文摘Methicllin-resistant Staphylococcus aureus(MRSA)is an important etiology of pneumonia.Interleukin(L)-9 is a T helper 9(Th9)cytokine and participates in the pathogenesis of infectious diseases.Here,we investigated the role of IL9 by using an MRSA pneumonia animal model.The BALB/c mice underwent nasal inhalation with an ST239 MRSA strain to establish the mouse model of MRSA pneumonia,and a subset of mice were intravenously injected with IL9 neutral-izing antibody or immunoglobulin (lg)G.At 3 and 8 days postinfection,the peripheral blood,bronchioalveolar lavage fluid(BALF),and lung tissues were collected.The frequencies of Th9 cells and the levels of cytokines in peripheral blood,BALE and lung tissues were determined by flow cytometry and enzyme-linked immunosorbent assay(ELISA),respectively.The colony counts of MRSA in BALF and lung tissue were detected.The lung pathological changes were examined using hematoxylin and eosin staining.Data from flow cytometry,qRTPCR,and ELISA showed that MRSA infected mice exhibited higher frequency of Th9 cells and higher IL9 mRNA and protein levels in the peripheral blood,BALF and lung tissues of mice.In contrast,the neutralization of IL9 abrogated MRSA inoculation-induced Th9 cell generation and IL9 production in BALF and lung tissues.Furthermore,bacterial counting and histological examination showed that the numbers of bacteria in BALF and lungs and the lung pathological scores induced by MRSA inoculation were attenuated by the neutralization of IL9.Moreover,cell counting and ELISA results demonstrated that IL9 neutralization diminished the MRSA inoculation-induced count of neutrophils and macrophages and levels of pro-inflammatory cytokines in BALF Collectively,IL9 neutralization attenuated inflammation of MRSA pneumonia by regulating Th9/L9 expression. | Weihua Xu Keyin Tian Xiaoshuang Li Shihai Zhang | 2020 | Acta Biochimica et Biophysica Sinica2020，52，2： | 3 |
| 10 | Recent progress of porcine milk components and mammary gland function显示文摘As the only nutritional source for newborn piglets,porcine colostrum and milk contain critical nutritional and immunological components including carbohydrates,lipids,and proteins(immunoglobulins).However,porcine milk composition is more complex than these three components.Recently,scientists identified additional and novel components of sow colostrum and milk,including exosomes,oligosaccharides,and bacteria,which possibly act as biological signals and modulate the intestinal environment and immune status in piglets and later in life.Evaluation of these nutritional and non-nutritional components in porcine milk will help better understand the nutritional and biological function of porcine colostrum and milk.Furthermore,some important functions of the porcine mammary gland have been reported in recent published literature.These preliminary studies hypothesized how glucose,amino acids,and fatty acids are transported from maternal blood to the porcine mammary gland for milk synthesis.Therefore,we summarized recent reports on sow milk composition and porcine mammary gland function in this review,with particular emphasis on macronutrient transfer and synthesis mechanisms,which might offer a possible approach for regulation of milk synthesis in the future. | Shihai Zhang Fang Chen Yinzhi Zhang Yantao Lv Jinghui Heng Tian Min Lilang Li Wutai Guan | 2019 | Journal of Animal Science and Biotechnology2019，10，1： | 2 |
| 11 | A hazard analysis via an improved timed colored petri net with time–space coupling safety constraint显示文摘Petri nets are graphical and mathematical tools that are applicable to many systems for modeling, simulation, and analysis. With the emergence of the concept of partitioning in time and space domains proposed in avionics application standard software interface(ARINC 653), it has become difficult to analyze time–space coupling hazards resulting from resource partitioning using classical or advanced Petri nets. In this paper, we propose a time–space coupling safety constraint and an improved timed colored Petri net with imposed time–space coupling safety constraints(TCCP-NET) to fill this requirement gap. Time–space coupling hazard analysis is conducted in three steps: specification modeling, simulation execution, and results analysis. A TCCP-NET is employed to model and analyze integrated modular avionics(IMA), a real-time, safety-critical system. The analysis results are used to verify whether there exist time–space coupling hazards at runtime. The method we propose demonstrates superior modeling of safety-critical real-time systems as it can specify resource allocations in both time and space domains. TCCP-NETs can effectively detect underlying time–space coupling hazards. | Li Zelin Wang Shihai Zhao Tingdi Liu Bin | 2016 | Chinese Journal of Aeronautics2016，29，4： | 2 |
| 12 | A block particle coupled model and its application to landslides显示文摘To simulate the progressive failure of slope,a block particle coupled model is introduced.Particle oriented cell mapping(POCM)algorithm is used to enhance the search efficiency,and particlepoint,particle-edge,particle-face contact detecting method is adopted to establish contact pair between particles and blocks precisely.Strain softening Mohr Coulomb model with tensile cutoff is adopted for blocks,and brittle Mohr Coulomb model is used for particles.The particle-block replacement approach is used to describe the fracture and fragmentation process of continuum media.Once the cohesion or tensile strength of one block reaches zero,the block will be deleted,and particles are generated at the same place with all information inherited from the deleted block.Some numerical cases related to landslides demonstrate the precision and rationality of the coupled model. | Chun Feng Shihai Li Qindong Lin | 2020 | Theoretical & Applied Mechanics Letters2020，10，2： | 2 |
| 13 | Comparative proteomics analyses of intraspecific differences in the response of Stipa purpurea to drought显示文摘Stipa purpurea is widely distributed along a large precipitation gradient on the Tibetan Plateau.This implies that S.purpurea from different populations may have different responses to drought stress.To explore this we compared the morphological and physiological changes of S.purpurea seedlings cultivated from seeds from Gar County and Nagqu County after 7 and 14 days of drought stress and subsequent rewatering.The results showed that S.purpurea plants from the more arid Gar area were more tolerant to drought stress than that from Nagqu.To investigate the potential mechanisms underlying this difference,we used i TRAQ quantitative proteomics technology to analyze protein dynamics in S.purpurea samples treated with 7 days of drought stress and subsequent re-watering.The results indicated that,during the process of drought and re-watering treatments,there were differentially expressed proteins in either or both S.purpurea populations.These differential proteins were divided into 24 functional categories that were mainly associated with stress response,the antioxidant system,photosynthesis,carbohydrate metabolism,and post-translational modifications.According to these results,we concluded that the molecular basis of stronger drought resistance likely lies in the specific up-regulation or higher expression of many proteins involved in stress response,the antioxidant system,post-translational modification and osmotic regulation in S.purpurea from Gar County compared with that from Nagqu.This study improves our understanding of the intraspecific differences in drought resistance within S.purpurea populations,which helps to understand the distribution of S.purpurea along the moisture gradient,as well as the effect of climate change on this species. | Xiong Li Yunqiang Yang Shihai Yang Xudong Sun Xin Yin Youjie Zhao Yongping Yang | 2016 | 植物分类与资源学报2016，38，2： | 2 |
| 14 | Robust secrecy beamforming for full-duplex two-way relay networks under imperfect channel state information显示文摘Consider a two-way amplify-and-forward(AF) relay network where two legitimate nodes communicate through a relay in the presence of an eavesdropper. Assuming full duplexity at the legitimate nodes and the relay, a robust artificial noise(AN)-aided AF scheme is proposed to maximize the worst-case sum secrecy rate under imperfect channel state information(CSI) of the eavesdropper. This robust sum secrecy rate maximization(SSRM) problem is formulated as a max-min semi-infinite problem and is tackled by the semidefinite relaxation(SDR) method. In particular, we first convert the max-min semi-infinite problem into a maximization problem with a finite number of constraints. Then, an efficient two-block alternating difference-of-concave(DC) programming approach is proposed to iteratively solve the SDR problem, with one of the blocks computed in closed form. In addition, a specific robust rank-one solution construction procedure is presented to extract a feasible solution for the original robust SSRM problem from the SDR solution. The efficacy of the proposed method is demonstrated by numerical simulations. | Si LI Qiang LI Shihai SHAO | 2018 | Science China(Information Sciences)2018，61，2： | 2 |
| 15 | Comparisons on Mineralogy and Lithology between Paleozoic Marine and Lacustrine Dolostones, Northern China显示文摘1 Introduction Dolomite[Ca Mg(CO3)2],a common mineral in carbonate rocks,can be found in various geological settings from Precambrian to modern age,and is widely reported in almost all sedimentary and | LI Hong LIU Yiqun NIU Yuanzhe FENG Shihai LEI Yun LIU Yongjie | 2017 | Acta Geologica Sinica(English Edition)2017，91，S1： | 2 |
| 16 | Gaseous hydrogen storage properties of Mg-Y-Ni-Cu alloys prepared by melt spinning显示文摘For purpose of promoting the hydrogen absorption and desorption thermodynamics and kinetics properties of Mg-Ni-based alloys, partially substituting Y and Cu for Mg and Ni respectively and melt spinning technique were applied for getting Mg25-xYxNi9 Cu(χ = 0-7) alloys. Their microstructures and phases were characterized with the help of X-ray diffraction and transmission electron microscopy. Their hydrogen absorbing and desorbing properties were tested by a Sievert apparatus, DSC, and TGA, which were connected with a H2 detector. In order to estimate the dehydrogenation activation energy of alloy hydride, both Arrhenius and Kissinger methods were applied for calculation. It is found that their hydriding kinetics notably declines, however, their hydrogen desorption kinetics conspicuously improves, with spinning rate and Y content increasing. Their hydrogen desorption activation energy markedly decreases under the same constraint, and it is found that melt spinning and Y substituting Mg improve the real driving force for dehydrogenation. As for the tendency of hydrogen absorption capacity,it presents an elevation firstly and soon after a decline with the rising of spinning rate, however, it always lowers with Y content growing. With Y content and spinning rate increasing, their thermodynamic parameters(△H and △S absolute values) visibly decrease, and the starting hydrogen desorption temperatures of alloy hydrides obviously lower. | Yanghuan Zhang Yaqin Li Wei Zhang Zeming Yuan Zhonghui Hou Yan Qi Shihai Guo | 2019 | Journal of Rare Earths2019，37，7： | 2 |
| 17 | Expression of HIF-1α and CAIX in nasopharyngeal carcinoma and their correlation with patients’ prognosis显示文摘 | Yuhan Chen Xianming Li Shihai Wu Gang Xu Yayan Zhou Long Gong Zihuang Li Dong Yang | 2014 | Medical Oncology2014，，12： | 1 |
| 18 | Hydrogen Storage Kinetics of Nanocrystalline and Amorphous LaMg_(12)-Type Alloy–Ni Composites Synthesized by Mechanical Milling显示文摘The nanocrystalline and amorphous LaMg_(11)Ni + x wt% Ni(x = 100, 200) composites were synthesized by the mechanical milling, and their gaseous and electrochemical hydrogen storage kinetics performance were systematically investigated. The results indicate that the as-milled composites exhibit excellent hydrogen storage kinetic performances, and increasing Ni content significantly facilitates the improvement of the hydrogen storage kinetics properties of the composites. The gaseous and electrochemical hydrogen storage kinetics of the composites reaches a maximum value with the variation of milling time.Increasing Ni content and milling time both make the hydrogen desorption activation energy lower, which are responsible for the enhancement in the hydrogen storage kinetics properties of the composites. The diffusion coefficient of hydrogen atom and activation enthalpy of charge transfer on the surface of the as-milled composites were also calculated, which are considered to be the dominated factors for the electrochemical high rate discharge ability. | Yanghuan Zhang Baowei Li Huiping Ren Tai Yang Shihai Guo Yan Qi Dongliang Zhao | 2016 | Journal of Materials Science & Technology2016，32，3： | 1 |
| 19 | A Comparative Study on Different Parallel Solvers for Nonlinear Analysis of Complex Structures显示文摘 | Lei Zhang Guoxin Zhang Lixiang Wang Zhaosong Ma Shihai Li Zhiqiang Hu | 2013 | Mathematical Problems in Engineering2013，，： | 1 |
| 20 | Molecularly imprinted polymer-based solid phase clean-up for analysis of ochratoxin A in ginger and LC-MS/MS confirmation显示文摘 | Jiliang Cao Shujun Zhou Weijun Kong Meihua Yang Li Wan Shihai Yang | 2013 | Food Control2013，，2： | 1 |
您所在的机构暂未开通此部分的功能，请联系管理员