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Large Bi-Polar Signature in a Perpendicular Electric Field of Two-Dimensional Electrostatic Solitary Waves Associated with Magnetic Reconnection: Statistics and Discussion

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Chinese Physics Letters 2013年第1期30卷 231-234页

作者： li shi-you ZHANG shi-Feng DENG Xiao-Hua CAI Hong College of Aerospace Science and Engineering National University of Defense TechnologyChangsha 410073 Department of Space Physics Wuhan UniversityWuhan 430072 Nanchang University Nanchang 330031

More than 300 electrostatic solitary waves(ESWs)with a large perpendicular component which is a bi-polar waveform structure are observed in the boundary layer within the magnetic reconnection diffusion region in the near-Earth *** ESWs are called two-dimensional ESWs.A Singe-reconnection-based-statistical study of two-dimensional ESWs shows that:(1)ESWs can be continuously observed in the plasma sheet boundary layer(PSBL)associated with the magnetic reconnection diffusion region,and their amplitude ranges are mainly from several tens to hundreds ofμV/m;(2)both one-dimension-like ESWs(very small magnitude on E⊥)and two-dimension-like ESWs(large magnitude on E⊥,which are even comparable to that in the E||)are observed within a small time interval;(3)within the observation time spans,more than 61%of ESWs are regarded as two-dimensional ESWs for the I_(2)D>20%.We discuss the bi-polar structure in E⊥.The observation of ESWs with a large bi-polar structure in the perpendicular electric field gives evidence that the unique waveform differs from previous understanding from observations and simulations which suggests that it should be a uni-polar waveform structure in the E⊥of ESWs.

关键词： structure dimension Polar

Spatial Evolution of Electrostatic Solitary Waves along Plasma Sheet Boundary Layer Adjacent to the Magnetic Reconnection X-line

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Chinese Physics Letters 2012年第8期29卷 313-317页

Analysis on the spatial structure of electrostatic solitary waves(ESWs)along the plasma sheet boundary layer(PSBL)near an on-going magnetic reconnection X-line is *** of the ESWs in the PSBL of R3 region near reconnection X-line are propagating earthwards away from the reconnecting *** analysis of their spatial structure shows that,when ESWs propagate along the ambient field in the PSBL,outwards from the magnetic reconnection X-line,their amplitude will finally attenuate and thus the electron hole will fade away but their spatial scale remains ***,the spatial structure of propagating ESWs evolves from 1-D-like to 2-D-like though totally in a 1-D structure.

关键词： Spatial propagating structure

Effect of TiO_(2) addition on microstructures and properties of Mgo-Cao refractory aggregates

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Journal of Iron and Steel Research International 2024年第6期31卷 1547-1554页

作者： Shuai Zhang Jing-ran Wang Yuan-gao li Feng-you li Wen Yan Hui-ying shi The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081HubeiChina Joint International Research Laboratory of Refractories and Metallurgy Wuhan 430081HubeiChina Shanxi Luweibao Taigang Refractory Co. Ltd.Taiyuan 030003ShanxiChina

MgO-CaO(40 wt.%CaO)refractory aggregates were prepared using the calcined dolomite and light-burned magnesia fine powder as raw materials and TiO_(2) as *** effect of TiO_(2) on their phase composition,microstructures and properties was investigated by X-ray diffraction and scanning electron *** properties such as bulk density,apparent porosity,relative aggregate tube strength and hydration resistance were also *** results showed that the CaTiO_(3) generated by the reaction between CaO and TiO_(2) was distributed around the CaO grain boundaries and intermittently distributed with MgO,which formed an isolation layer around CaO and greatly improved the hydration ***,the introduction of TiO_(2) promoted sintering and increased the grain size,further improving the strengths and hydration resistance of the *** addition,the most significant enhancement in the hydration resistance and strengths of the samples was achieved when 1.0-2.0 wt.%TiO_(2) was *** this case,the relative strength of aggregate increased from 33.3% to 37.3%-43.1%,and the mass gain after the hydration test decreased from 3.13% to 1.26%-1.45%.

关键词： MgO-CaO refractory aggregate TiO_(2)addition Phase composition Microstructure Hydration resistance

Application and Experiment on the Least-action Principle of Explosive Welding of Stainless Steel/Steel

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Journal of Iron and Steel Research International 2014年第6期21卷 625-629页

作者： Chang-gen shi Yu WANG Si-jing li Jun you PLA University of Science and Technology 78138 Troops of PLA

In nature, many physical phenomena follow the least-action principle, which is also abided by the course of explosive welding of stainless steel/steel. The optimal welding interface can be obtained with the least explosive charge by theoretical analysis and interface test. The bonding energy can be acknowledged as the ＂action＂ in explosive welding. To minimize the bonding energy, these rules must be followed such as the lower limit of explosive charge, the upper limit of span and the explosive of critical explosion velocity. The principle of least-action is achieved in the course of explosive welding, and the interface will be optimum.

关键词： explosive welding least-action principle lower limit rule bonding interface

Synergistic antitumor effect of TRAIL and doxorubicin on colon cancer cell line SW480

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World Journal of Gastroenterology 2003年第6期9卷 1241-1245页

作者： li-HongXu Chang-ShengDeng you-QingZhu shi-Quanliu Dong-Zhouliu DepartmentofGastroenterology ZhongnanHospitalofWuhanUniversityWuhan430071HubeiProvinceChina DepartmentofOncology ZhongnanHospitalofWuhanUniversityWuhan430071HubeiProvinceChina DepartmentofNephrology RenminHospotalofWuhanUniversityWuhan430060HubeiProvinceChina

AIM: TRAIL (tumor necrosis factor-related apoptosis-inducing ligand) has been reported to specifically induce apoptosis of cancer cells although only a small percentage of cell lines were sensitive to it. Cell lines not responding to TRAIL in vitro were said to be more prone to apoptosis when TRAIL was combined with another anticancer ***, factors affecting drug-sensitivity involve many apoptosis-related proteins, including p53. The expression of wild-type p53 gene was proposed as an important premise for tumor cells responding to chemotherapy. The present study was to investigate the cell killing action of TRAIL on colon cancer cell line SW480, its synergistic effect with doxorubicin, and the possible ***: SW480 cells were cultured in the regular condition and incubated with different levels of *** changes in these cells after treatment were observed under phase-contrast microscope and cytotoxicity by TRAIL alone and in combination with doxorubicin was quantified by a 1-day microculture tetrazolium dye (MTT) assay. In addition, flow cytometry assay (FCM) and transmission electron microscopy were used to detect apoptosis among these cells. Variation of p53 protein level among different groups according to concentrations of agents was measured by Western blot ***: (1) SW480 cells were not sensitive to TRAIL,with IC50>l mg·L^1 and dose-independent cytotoxicity. (2)SW480 cells were sensitive to doxorubicin at a certain degree,with dose-dependent cytotoxicity and IC50=65.25±3.48μmol·L^-1. (3) TRAIL could synergize with doxorubicin to kill SW480 cells effectively, which was represented by the boosted killing effect of doxorubicin on theses cells. IC50 of doxorubicin against SW480 cells sharply reduced when it was combined with TRAIL. (4) Subtoxic TRAIL (100 μg·L^-1),combined with subtoxic doxorubicin (0.86 μmol·L^-1), could kill SW480 cells sufficiently. Cytotoxicity by MTT assay arrived at 80.12±2.67 %, which was signi

关键词：结肠癌 SW480细胞系化学疗法阿霉素肿瘤坏死因子相关凋亡诱导配体

Evaluating the Accuracy of ERA5 Wave Reanalysis in the Water Around China

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Journal of Ocean University of China 2021年第1期20卷 1-9页

作者： shi Hongyuan CAO Xuefeng li Qingjie li Delei SUN Jiacheng you Zaijin SUN Qingying School of Civil Engineering Ludong UniversityYantai 264025China Institute of Ports and Coastal Disaster Mitigation Ludong UniversityYantai 264025China National Marine Environmental Monitoring Center Dalian 116023China Yantai Marine Environmental Monitoring Central Station State Oceanic AdministrationYantai 264006China Key Laboratory of Ocean Circulation and Waves Institute of OceanologyChinese Academy of SciencesQingdao 266071China

Wave parameters, such as wave height and wave period, are important for human activities, such as navigation, ocean engineering and sediment transport, etc. In this study, wave data from six buoys around Chinese waters, are used to assess the quality of wave height and wave period in the ERA5 reanalysis of the European Centre for Medium-Range Weather Forecasts. Annual hourly data with temporal resolution are used. The difference between the significant wave height(SWH) of ERA 5 and that of the buoy varies from-0.35 m to 0.30 m for the three shallow locations;for the three deep locations, the variation ranges from-0.09 m to 0.09 m. The ERA5 SWH data show positive biases, indicating an overall overestimation for all locations, except for E2 and S1 where underestimation is observed. During the tropical cyclone period, a large(about 32%) underestimation of the maximum SWH in the ERA5 data is observed. Hence, the ERA5 SWH data cannot be used for design applications without site-specific validation. The difference between the annual wave period from ERA5 and the mean wave period from the buoys varies from-1.31 s to 0.4 s. Inter-comparisons suggest that the ERA5 dataset is consistent with the annual mean SWH. However, for the average period, the performance is not good, and half of the correlation coefficients in the four points are less 50%. Overall, the deep water area simulation effect is better than that in the shallow water.

关键词： wave hindcasting reanalysis ERA5 wave height wave period

Patterns of human-wildlife conflict and compensation practices around Daxueshan Nature Reserve, China

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Zoological Research 2018年第6期39卷 406-412页

作者： Cheng Huang Xue-you li liu-Jun shi Xue-Long Jiang Kunming Institute of Zoology Chinese Academy of Sciences Kunming Yunnan 650223 China Kunming College of life Sciences University of Chinese Academy of Sciences Kunming Yunnan 650223 China Daxueshan Nature Reserve Yongde Yunnan 677600 China

Understanding the spatial patterns of human-wildlife conflict is essential to inform management decisions to encourage coexistence, but it is constrained by the lack of spatially-explicit data. We collected spatially-implicit data of human-wildlife conflicts from 2009-2015 around Daxueshan Nature Reserve, Yunnan, China, and investigated the patterns and drivers of these conflicts. A questionnaire was also designed to capture local resident attitudes toward insurance-based compensation for the losses caused by targeted wildlife. We found that the Asiatic black bear （Ursus thibetanus） was the most conflict-prone animal around the reserve, followed by the rhesus macaque （Macaca mulatta） and Southeast Asian sambar （Cervus equinus）. Conflicts were unevenly distributed among seasons, villages, and communities, with several grids identified as conflict hotspots. Poisson models revealed that human-bear conflicts were negatively related to distance to the reserve and proportion of forest, but positively correlated to the proportion of cropland. Binomial models showed that communities affected by crop depredation were positively correlated with the proportion of cropland and negatively correlated with distance to the reserve, whereas communities affected by livestock depredation were negatively correlated with the proportion of cropland. The insurance-based scheme has compensated over 90% of losses, to the satisfaction of 90.6% of respondents. Our results suggest that human-bear conflict could be potentially reduced by eliminating food crops near the reserve boundary and livestock grazing at conflict *** addition, the insurance-based scheme could be replicated at a broader scale with improvement in loss assessment.

关键词： Human-wildlife conflict Asiatic black bear Spatial heterogeneity Insurance scheme Daxueshan Nature Reserve

Functions and Application of the AP2/ERF Transcription Factor Family in Crop Improvement

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Journal of Integrative Plant Biology 2011年第7期53卷 570-585页

作者： Zhao-shi Xu Ming Chen lian-Cheng li you-Zhi Ma National Key Facility of Crop Gene Resources and Genetic Improvement (NFCRI) Key Laboratory of Crop Genetics and Breeding Ministry of Agriculture Institute of Crop Science Chinese Academy of Agriculture Sciences (CAAS) Beijing 100081 China

Plants have acquired sophisticated stress response systems to adapt to changing environments. It is important to understand plants＇ stress response mechanisms in the effort to improve crop productivity under stressful conditions. The AP2/ERF transcription factors are known to regulate diverse processes of plant development and stress responses. In this study, the molecular characteristics and biological functions of AP2/ERFs in a variety of plant species were analyzed. AP2/ERFs, especially those in DREB and ERF subfamilies, are ideal candidates for crop improvement because their overexpression enhances tolerances to drought, salt, freezing, as well as resistances to multiple diseases in the transgenic plants. The comprehensive analysis of physiological functions is useful in elucidating the biological roles of AP2/ERF family genes in gene interaction, pathway regulation, and defense response under stress environments, which should provide new opportunities for the crop tolerance engineering.

关键词： AP2/ERF gene regulation signal pathway stress tolerance transgenic plant

Inherent relationship between process parameters,crystallization and mechanical properties of continuous carbon fiber reinforced PEEK composites

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Defence Technology（防务技术） 2023年第6期24卷 269-284页

作者： Xiao-long Ma li-hua Wen shi-yu Wang Jin-you Xiao Wen-hao li Xiao Hou School of Astronautics Northwestern Polytechnical UniversityXi'an710072China China Aerospace Science and Technology Corporation Beijing100048China

High-performance thermoplastic composites have been developed as significant structural materials for cutting-edge equipment in the aerospace and defence ***,the internal mechanism of processing parameters on mechanical properties in the manufacturing process of thermoplastic composite structures is still a serious *** purpose of this study is to investigate the process/crystallization/property relationships for continuous carbon fiber(CF)reinforced polyether-ether-ketone(PEEK)*** composite laminates are fabricated according to orthogonal experiments via the thermoforming *** mechanical performance is investigated in terms of crystallization properties and fracture morphology *** results show that the mechanical performance and crystallization properties of thermoplastic composites are significantly affected by the coupling of processing *** increased molding temperature,pressure,and holding time improve the degree of fiber/matrix infiltration and affect the crystallinity and crystalline morphology of the matrix,which further influences the mechanical properties of the *** is reflected in the test results that crystallinity has an approximately linear effect on mode-I interlaminar fracture toughness and transverse flexural *** well as the higher molding temperature can destroy the pre-existent crystals to improve the toughness of the matrix,and the well-defined crystalline structures can be observed when fabricated at higher temperatures and longer periods of holding time.

关键词： Polymer matrix composites Thermoplastic Processing parameters Mechanical properties Crystallization