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不同体育生活方式大学生体质状况的探讨与分析

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首都体育学院学报 2009年第6期21卷 737-739页

作者：李恺宪南京林业大学体育部江苏南京210039

为探讨不同体育生活方式大学生的体质状况以及两者相互关系,采用文献资料、问卷调查、专家访谈等研究方法,对江苏地区普通高校大学生的体育生活方式进行问卷调查,结果显示:体育生活方式存在较为明显的年级差异,一、二、三年级良好体育... 详细信息

为探讨不同体育生活方式大学生的体质状况以及两者相互关系,采用文献资料、问卷调查、专家访谈等研究方法,对江苏地区普通高校大学生的体育生活方式进行问卷调查,结果显示:体育生活方式存在较为明显的年级差异,一、二、三年级良好体育生活方式的学生比例逐年增多,至四年级时突然下降至最低;对调查样本中具有不同体育生活方式大学生的体质状况进行对比分析,结果表明,具有良好体育生活方式特征的大学生体质状况明显好于另一部分大学生;因此,建立良好的体育生活方式,可以提高身体机能素质,促进柔韧、速度和耐力素质的发展,最终促进大学生体质的全面发展。

关键词：体育生活方式大学生体质健康

C_(60)对DNA光动力学作用的FT-Raman光谱研究

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中国激光 1998年第7期25卷 661-666页

作者：严庆丰钱凯先李文铸浙江大学生物科学与技术系

采用傅里叶变换激光Ｒａｍａｎ光谱术从分子水平研究了富勒烯Ｃ６０对小牛胸腺ＤＮＡ的光动力学作用。结果表明光激发Ｃ６０对ＤＮＡ各组分基团均有不同程度的损伤，其中ＤＮＡ的空间构像破坏显著，腺嘌呤次之，骨架磷酸基团、脱氧核糖... 详细信息

采用傅里叶变换激光Ｒａｍａｎ光谱术从分子水平研究了富勒烯Ｃ６０对小牛胸腺ＤＮＡ的光动力学作用。结果表明光激发Ｃ６０对ＤＮＡ各组分基团均有不同程度的损伤，其中ＤＮＡ的空间构像破坏显著，腺嘌呤次之，骨架磷酸基团、脱氧核糖、嘧啶环等也遭到破坏并导致ＤＮＡ链断裂。这种结果并非由于Ｃ６０与ＤＮＡ分子之间直接的电子相互作用，而是通过单线态氧（１Ｏ２）或·ＯＨ。

关键词： DNA 激光拉曼光谱术光动力学作用富勒烯碳60

我国部分普通高校体育俱乐部教学模式现状与发展对策的研究

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吉林体育学院学报 2007年第3期23卷 83-84页

作者：李恺宪王燕南京林业大学体育教育部江苏南京210037

运用问卷调查法、专家访谈法、文献资料法、归纳演绎法、数理统计等方法,对我国部分高校实施体育俱乐部教学模式的现状进行调研与分析,结果显示:我国高校体育俱乐部在组织管理、教学课程设置、师资配备、硬件设施、活动经费、考核与评... 详细信息

运用问卷调查法、专家访谈法、文献资料法、归纳演绎法、数理统计等方法,对我国部分高校实施体育俱乐部教学模式的现状进行调研与分析,结果显示:我国高校体育俱乐部在组织管理、教学课程设置、师资配备、硬件设施、活动经费、考核与评价、学习动机、参与态度等诸多方面还存在较为严重的共性问题与突出问题,成为制约其发展的瓶颈,为此提出了相应的改进措施与建设性意见,使之更趋完善,为高校体育的延续性教学提供一个契机。

关键词：中国部分高校体育俱乐部教学模式现状与对策

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运输顺槽深孔爆破断顶卸压护巷技术研究

山东煤炭科技 2024年第2期42卷 59-62页

作者：张杰李开贤陈勇兖矿能源集团股份有限公司济宁二号煤矿山东济宁272000

针对济宁二号煤矿93下11-2运输顺槽在采动影响下巷道围岩变形大、难维护的问题,结合深孔爆破切顶卸压技术原理和理论计算,确定了切顶高度45 m、切顶角度75°以及钻孔布置方式。现场工业试验表明,深孔爆破断顶卸压后,巷道顶底板变形约80.... 详细信息

针对济宁二号煤矿93下11-2运输顺槽在采动影响下巷道围岩变形大、难维护的问题,结合深孔爆破切顶卸压技术原理和理论计算,确定了切顶高度45 m、切顶角度75°以及钻孔布置方式。现场工业试验表明,深孔爆破断顶卸压后,巷道顶底板变形约80.5 mm,两帮移近量约71.8 mm,巷道围岩变形明显减小,取得了较好的效果。

关键词：采动煤巷爆破卸压

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川西断缝体储层封堵固壁钻井液技术

钻井液与完井液 2023年第5期40卷 556-562页

作者：高书阳汤志川宋碧涛李凯贤刘祚才页岩油气富集机理与有效开发国家重点实验室北京102206 中石化石油工程技术研究院有限公司北京102206 中石化西南石油工程有限公司四川德阳618000

为解决川西断缝体破碎性地层钻进过程中卡钻频发、成井难度大等技术难题,分析了该地层地质特征,实验研究了其井壁失稳机理。结果表明,川西断缝体破碎性地层岩石破碎、胶结程度弱,微裂隙发育,流体侵入后微裂缝扩展,损害岩石完整性及力学... 详细信息

为解决川西断缝体破碎性地层钻进过程中卡钻频发、成井难度大等技术难题,分析了该地层地质特征,实验研究了其井壁失稳机理。结果表明,川西断缝体破碎性地层岩石破碎、胶结程度弱,微裂隙发育,流体侵入后微裂缝扩展,损害岩石完整性及力学性能,改变井壁岩石有效应力状态,导致井壁垮塌。在此基础上,基于“封堵+固壁”技术对策,研制了抗高温化学固壁剂,优选了高效封堵剂,构建了断缝体地层封堵固壁井壁稳定钻井液体系,提升了钻井液的封堵固壁能力。该钻井液在M6等井进行了成功应用,维持了断缝体破碎性地层的井壁稳定性,具有良好的应用前景。

关键词：断缝体破碎性地层封堵固壁钻井液

A Unified Trajectory Optimization Approach for Long-Term and Reactive Motion Planning of Legged Locomotion

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Journal of Bionic Engineering 2023年第5期20卷 2108-2122页

作者： Yapeng Shi Bin Yu kaixian Ba Mantian li School of Mechanical Engineering Yanshan UniversityNo.438 West Hebei AvenueQinhuangdao066004HebeiPeople’s Republic of China State Key Laboratory of Robotics and System Harbin Institute of TechnologyHarbin150001People’s Republic of China

This paper proposes a unified trajectory optimization approach that simultaneously optimizes the trajectory of the center of mass and footholds for legged *** on a generic point-mass model,the approach is formulated as a nonlinear optimization problem,incorporating constraints such as robot kinematics,dynamics,ground reaction forces,obstacles,and target *** unified optimization approach can be applied to both long-term motion planning and the reactive online planning through the use of model predictive control,and it incorporates vector field guidance to converge to the long-term planned *** effectiveness of the approach is demonstrated through simulations and physical experiments,showing its ability to generate a variety of walking and jumping gaits,as well as transitions between them,and to perform reactive walking in obstructed environments.

关键词： Legged locomotion Motion planning Trajectory optimization Bionic robot

Water Soluble C_(60)-liposome and the Biological Effect of C_(60) to Human Cervix Cancer Cells

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Chinese Physics Letters 1994年第4期11卷 207-210页

作者： li Wenzhu QIAN kaixian HUANG Wendong ZHANG Xinxin CHEN Wanxi Department of Physics Zhejiang UniversityHangzhou 310027 Department of Biology Zhejiang UniversityHangzhou 310027 Department of Chemistry Zhejiang UniversityHangzhou 310027

A preparative technique to obtain water soluble C_(60)-liposome by means of molecular package of C_(60) with lecithin has been *** concentration of C_(60) presented in liposome is 1.09 x 10-4mol/*** molecular system of C_(60)-liposome with human cervix cancer cells is irradiated with laser(570nm,800mW),there is obvious biological effect of C_(60) to huma cervix cancer cells.

关键词： cervix cancer Cancer

Global Water Vapor Content Decreases from 2003 to 2012： An Analysis Based on MODIS Data

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Chinese Geographical Science 2017年第1期27卷 1-7页

作者： MAO Kebiao CHEN Jingming li Zhaoliang MA Ying SONG Yang TAN Xuelan Yang kaixian National Hulunber Grassland Ecosystem Observation and Research Station Institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural Sciences Beijing 100081 China Department of Geography University of Toronto Toronto M5S 3G3 Canada School of Geographical Sciences Northeast Normal University Changchun 130024 China College of Resources and Environments Hunan Agricultural University Changsha 410128 China Department of Geography University of Cincinnati Cincinnati 45221 USA

Water vapor in the earth′s upper atmosphere plays a crucial role in the radiative balance, hydrological process, and climate change. Based on the latest moderate-resolution imaging spectroradiometer(MODIS) data, this study probes the spatio-temporal variations of global water vapor content in the past decade. It is found that overall the global water vapor content declined from 2003 to 2012(slope b = –0.0149, R = 0.893, P = 0.0005). The decreasing trend over the ocean surface(b = –0.0170, R = 0.908, P = 0.0003) is more explicit than that over terrestrial surface(b = –0.0100, R = 0.782, P = 0.0070), more significant over the Northern Hemisphere(b = –0.0175, R = 0.923, P = 0.0001) than that over the Southern Hemisphere(b = –0.0123, R = 0.826, P = 0.0030). In addition, the analytical results indicate that water vapor content are decreasing obviously between latitude of 36°N and 36°S(b = 0.0224, R = 0.892, P = 0.0005), especially between latitude of 0°N and 36°N(b = 0.0263, R = 0.931, P = 0.0001), while the water vapor concentrations are increasing slightly in the Arctic regions(b = 0.0028, R = 0.612, P = 0.0590). The decreasing and spatial variation of water vapor content regulates the effects of carbon dioxide which is the main reason of the trend in global surface temperatures becoming nearly flat since the late 1990 s. The spatio-temporal variations of water vapor content also affect the growth and spatial distribution of global vegetation which also regulates the global surface temperature change, and the climate change is mainly caused by the earth's orbit position in the solar and galaxy system. A big data model based on gravitational-magmatic change with the solar or the galactic system is proposed to be built for analyzing how the earth's orbit position in the solar and galaxy system affects spatio-temporal variations of global water vapor content, vegetation and temperature at large spatio-temporal scale. This comprehensive examination of water vapor changes p

关键词： water vapor content climate change moderate-resolution imaging spectroradiometer(MODIS)

Global vegetation change analysis based on MODIS data in recent twelve years

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High Technology Letters 2016年第4期22卷 343-349页

作者：毛克彪 li Zhaoliang Chen Jingming Ma Ying liu Guang Tan Xuelan Yang kaixian National Hulunber Grassland Ecosystem Observation and Research Station Institute of Agricultural Resources and Regional PlanningChinese Academy of Agricultural Sciences International Institute for Earth System Science Nanjing University State Key Laboratory of Remote Sensing Science Institute of remote sensing and Digital Earth Research Institute and Beijing Normal University College of Resources and Environments Hunan Agricultural University Department of Geography University of Cincinnati

Vegetation cover change is critical for understanding impacts and responses of vegetation to climate change. A study found that vegetation in the regions between 45°N-70°N was increasing using normalized difference vegetation index( NDVI) from 1981 to 1991 ten years ago. The global vegetation growth has changed because of climate change in recent twelve years( 2001- 2012). After thorough analysis based on satellite data,it is found that it is evident that the global vegetation changed( NDVI) little,and it is increasing slightly in Northern hemisphere while it is decreasing slightly in Southern Hemisphere. For different latitudes,vegetation is increasing 0.17% every year from 60°N to 70 °N( R^2= 0.47,P > 0.013),while the vegetation is decreasing 0.11% every year from 10°N to 10° S( R^2= 0.54,P > 0.004). For different continents,the vegetation in South America is decreasing 0.16% every year( R^2= 0.78,P > 0.0001) and it is increasing 0.05% every year in Asia( R^2= 0.28,P > 0.072) and 0.25% every year in Oceania( R^2= 0.24,P > 0.1). The analysis of global vegetation in different seasons indicates that spatial distribution of global temperature and water vapor will affect the spatial distribution of vegetation,in turn,the spatial distribution of vegetation will also regulate the global temperature and water vapor spatial distribution at large scale. The growth and distribution of vegetation are mainly caused by the orbit of the celestial bodies,and a big data model based on gravitational-magmatic change with the solar or the galactic system as its center is proposed to be built for analyzing how the earth's orbit position in the solar and galaxy system affects spatial-temporal variations of global vegetation and temperature at large scale. These findings promise a holistic understanding of the global climate change and potential underlying mechanisms.

关键词： vegetation global climate change remote sensing