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平流层验证飞艇结构体系比较研究

宇航学报 2011年第4期32卷 713-720页

作者：高海健陈务军付功义上海交通大学空间结构研究中心上海200030

为研究平流层飞艇的受力、变形及合理的结构体系布局,根据平流层飞艇结构特点,提出了十种结构体系布局方案。基于浮力与重力作用下平衡形态的原理,建立平流层飞艇结构分析方法和各体系分析模型。以一个25m验证飞艇作为对象进行了系统的... 详细信息

为研究平流层飞艇的受力、变形及合理的结构体系布局,根据平流层飞艇结构特点,提出了十种结构体系布局方案。基于浮力与重力作用下平衡形态的原理,建立平流层飞艇结构分析方法和各体系分析模型。以一个25m验证飞艇作为对象进行了系统的数值分析,与工程弹性理论进行比较,论证了各体系的结构特点,最后提出合理的结构体系。本文对平流层飞艇结构设计具有参考价值。

关键词：平流层飞艇结构体系平衡形态

AT1 receptor in rostral ventrolateral medulla mediating blunted baroreceptor reflex in spontaneously hypertensive rats

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Acta Pharmacologica Sinica 2004年第11期 49-54页

作者： Xin-ya gao, Feng ZHANG, Ying HAN, Han-jun WANG, Ying ZHANG, Rui GUO, Guo-qing ZHUDepartment of Physiology, Nanjing Medical University, Nanjing 210029, China

AIM: To determine the role of AT 1 receptor in the rostral ventrolateral medulla (RVLM) in mediating the blunted baroreceptor reflex in spontaneously hypertensive rats (SHR). METHODS: Intravenous injections of graded doses of phenylephrine (1, 5, 10, 20, and 40 μg/kg) increased the blood pressure to elicit the baroreceptor reflex in both SHR and normotensive Wistar rats anesthetized with urethane. The baroreceptor reflex sensitivity (BRS) was determined before and after microinjection of Ang Ⅱ, losartan, or AT1 receptor antisense oligodeoxynucleotides into the RVLM. AT1 receptor protein level in the RVLM was measured by Western blotting. RESULTS: The BRS was significantly decreased in SHR compared with normal rats. Bilateral microinjection of AT1 receptor antagonist losartan (250 nmol/h) into the RVLM partly reversed the blunted BRS in SHR, but had no significant effect on the BRS in normal rats. Ang Ⅱ (1.5 nmol/h) significantly inhibited the BRS in normal rats, which was completely abolished by pretr

关键词： angiotensin Ⅱ antisense oligodeoxynucleotide hypertension baroreceptor reflex rostral ventrolat-eral medulla

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非饱和土中圆柱形衬砌隧道的瞬态动力响应

岩土力学 2022年第11期43卷 3185-3197页

作者：王滢王海萍高盟山东科技大学山东省土木工程防灾减灾重点实验室山东青岛266590 山东科技大学土木工程与建筑学院山东青岛266590

在以往关于圆柱形衬砌隧道的瞬态动力响应中,衬砌周围土体大多假定为弹性介质或饱和介质。然而,自然界中的土体大多为非饱和介质。考虑土体与衬砌结构的动力相互作用及动荷载引起的附加质量密度的影响,研究了瞬态荷载作用下非饱和土中... 详细信息

在以往关于圆柱形衬砌隧道的瞬态动力响应中,衬砌周围土体大多假定为弹性介质或饱和介质。然而,自然界中的土体大多为非饱和介质。考虑土体与衬砌结构的动力相互作用及动荷载引起的附加质量密度的影响,研究了瞬态荷载作用下非饱和土中无限长深埋圆柱形衬砌隧道的动力响应。基于多孔介质混合物理论和连续介质力学理论,建立了非饱和土中圆柱形衬砌隧道受到瞬态荷载作用时衬砌及周围土体的控制方程,利用Durbin数值反演法得到了衬砌及土体在时间域的动力响应。数值分析了饱和度对瞬态荷载下径向位移、径向应力、环向应力和孔隙水压力的影响。结果表明:饱和度对衬砌及周围土体的瞬态响应影响显著;饱和度对径向位移沿径向的衰减影响较小,对环向应力和孔隙压力沿径向的衰减影响较大。

关键词：非饱和土圆柱形衬砌隧道动力响应 Laplace变换饱和度

Analysis of vegetation dynamics and driving forces in Ordos: 2000-2019

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Ecological Economy 2020年第3期16卷 162-175页

作者： ZHAO Chuan-wu YAN Yue-guan GUO Wei gao Shang-qing College of Geoscience and Surveying Engineering China University of Mining and TechnologyBeijing 100083CHINA Graduate School of Education Beijing Foreign Studies UniversityBeijing 100089CHINA

As a typical resource-based city,Ordos has a rapid economic *** studies mostly focused on vegetation changes monitoring,and rarely discuss socioeconomic impacts on vegetation *** on MOD13Q1 data,climate data and 11 socioeconomic indicators from 2000 to 2019,combined with GIS technology and statistical methods,the spatiotemporal changes of Ordos vegetation and its influencing factors were *** results show that:(1)In the past 20 years,the NDVI value of Ordos ranged from 0.233 to 0.395,showing a fluctuating growth trend with a growth rate of 0.058/10a;the NDVI values of the eight counties under its jurisdiction also showed a fluctuating growth trend,but there were differences among regions.(2)Spatially,the vegetation in Ordos is high in the northeast and low in the *** area of low vegetation area is 54200 km2,accounting for 62.39%of the total area of *** area of high vegetation area is only 19900 km2,mainly concentrated in the Yellow River impact area in the north of Dalate Banner.(3)In terms of spatial changes,the area of the vegetation improvement area is much larger than that of the vegetation degradation area,accounting for 52.38%of the total area of ordos,while the vegetation degradation area only accounts for 4.10%.(4)NDVI value showed a significant positive correlation with rainfall,the correlation coefficient is 0.802(P0.05);the correlation coefficient with sunshine hours and humidity is negative;the correlation coefficient between the change of NDVI and the accumulated rainfall in the month is larger,and the correlation coefficient with the temperature of one month ago is larger.(5)The NDVI change was extremely significantly positively correlated with the 11 socioeconomic indicators,with a correlation of 0.728-0.796(P<0.01).From 2000 to 2019,the restoration effect of Ordos vegetation was *** and temperature are the main factors affecting

关键词： ordos NDVI climate factors lag effect economic indicators

日本高校图书馆联盟的营销策略应用——以JUSTICE为例

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图书馆 2017年第6期 84-90页

作者：刘青高波华南师范大学经济与管理学院广州510063

高校图书馆联盟面临竞争激烈、成本增加、经费缩减及用户需求多样化等挑战,引入营销理论,有助于图书馆联盟提高购买力和谈判效果,推广图书馆的产品和服务,降低管理运营成本,实现组织目标。笔者以JUSTICE为例,结合联盟组织结构,运用6P营... 详细信息

高校图书馆联盟面临竞争激烈、成本增加、经费缩减及用户需求多样化等挑战,引入营销理论,有助于图书馆联盟提高购买力和谈判效果,推广图书馆的产品和服务,降低管理运营成本,实现组织目标。笔者以JUSTICE为例,结合联盟组织结构,运用6P营销理论,调查日本高校图书馆联盟的营销策略,分析JUSTICE在成员关系、部门分工、成本控制、人员培训方面的特点,为我国图书馆联盟的发展提供参考。

关键词：营销策略图书馆营销 JUSTICE 高校图书馆联盟

Synthesis and Optical Properties of Ce-doped ZnO

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Chemical Research in Chinese Universities 2008年第3期24卷 266-269页

作者： YANG Jing-hai gao Ming ZHANG Yong-jun YANG Li-li LANG Ji-hui WANG Dan-dan WANG Ya-xin LIU Hui-lian FAN Hou-gang WEI Mao-bin LIU Fu-zhu The Institute of Condensed State Physics Jilin Normal University Siping 136000 P R. China Key Laboratory of Excited State Processes Changehun Institute of Optics Fine Mechanics and Physics Chinese Academy of Sciences Changehun 130033 P R. China School of Material Science and Engineering Jiangsu University Zhenjiang 210013 P. R. China

ZnO nanorods were synthesized using the sol-gel method, and the effects of annealing temperature and Ce doping on the morphologies and optical properties of ZnO nanostructures were investigated in detail. The XRD measurements showed that the as-synthesized ZnO nanostructures had a hexagonal wurtzite structure. SEM images showed that uniform nanorods formed at 900 °C. Photoluminescence measurements showed an ultraviolet emission peak and a relatively broad visible light emission peak for the samples sintered at different temperatures. The UV emission peak bathochromically shifted when the annealing temperature rose from 850 to 1000 °C. Ce doping decreased the synthesized temperature of the ZnO nanorods to 500 °C, and the UV peaks hypsochromically shifted.

关键词： Annealing temperature Ce-doped ZnO Optical property

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层状地基中大直径端承桩的竖向振动特性研究

岩石力学与工程学报 2014年第A2期33卷 4193-4202页

作者：任青高战士吕洪勇上海理工大学土木工程系上海200093

大直径端承桩广泛地应用于近海工程和高层建筑中,首先总结了经典土体振动平面应变模型的局限性,在此基础上提出改进模型,通过合理选择参数,使得改进模型可以考虑土体水平振动对于竖向振动的影响,通过与经典解的比较,证明了本文解的合理... 详细信息

大直径端承桩广泛地应用于近海工程和高层建筑中,首先总结了经典土体振动平面应变模型的局限性,在此基础上提出改进模型,通过合理选择参数,使得改进模型可以考虑土体水平振动对于竖向振动的影响,通过与经典解的比较,证明了本文解的合理性。然后,将改进的土体振动模型应用于大直径端承桩的竖向振动分析中,给出层状地基中大直径端承桩的动阻抗和动内力。通过分析得出,长细比、土体泊松比和桩–土相对刚度是影响大直径桩动力阻抗的主要因素。最后,将本文模型用于分析近海工程大直径桩基础的动力频响特性,计算结果与三维有限元解一致,说明本文模型能够更为准确地预测大直径桩的振动特性。

关键词：桩基础大直径桩平面应变传递矩阵法动力响应

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钢制储液罐的幂次失效模型及地震力折减

浙江大学学报（工学版） 2014年第7期48卷 1202-1208页

作者：杨宏康高博青浙江大学空间结构研究中心浙江杭州310058 碧桂园物业发展有限公司广东佛山528312

为了反映钢制储液罐的渐进失效趋势并合理地量化弹塑性地震力,采用流固耦合系统的单向动力推覆分析,建立反应谱层次的幂次失效模型.根据该模型构建等向强化的广义本构关系,在特定延性下迭代求解地震力折减系数Ry.结果表明,幂次失效模型... 详细信息

为了反映钢制储液罐的渐进失效趋势并合理地量化弹塑性地震力,采用流固耦合系统的单向动力推覆分析,建立反应谱层次的幂次失效模型.根据该模型构建等向强化的广义本构关系,在特定延性下迭代求解地震力折减系数Ry.结果表明,幂次失效模型下的地震力折减系数变异性较小,双线性滞回模型下的地震力折减系数会导致过于保守或偏于危险的地震力折减.选取40条最不利地震动并按场地分类,幂次失效模型下的地震力折减系数的均值略低于目标延性值,更符合长周期结构的等位移准则.GB50341与SH/T3026规定的地震力折减系数高于API650与EN1998-4,建议将地震力折减系数调整至2.0,应进一步细化边界条件的影响.

关键词：钢制储液罐弹塑性动力推覆幂次失效地震力折减

A Comparison of the Transradial and Transfemoral Approaches for the Angiography and Intervention in Patients with a History of Coronary Artery Bypass Surgery： In-hospital and 1-year Follow-up Results

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Chinese Medical Journal 2015年第6期128卷 762-767页

作者： Pei-Yuan He Yue-Jin Yang Shu-Bin Qiao Bo Xu Min Yao Yong-Jian Wu Jin-qing Yuan Jue Chen hai-Bo Liu Jun Dai Xin-Ran Tang Yang Wang Wei Li Run-Lin gao Department of Cardiology Cardiovascular Institute and Fuwai Hospital Chinese Academy of Medical Sciences and Peking Union Medical College Beiiinq 100037 China Medical Research and Biometrics Center Cardiovascular Institute and Fuwai Hospital Chinese Academy of Medical Sciences and Peking Union Medical College Beijing 100037 China

Background:Percutaneous coronary intervention (PCI) through transradial approach (TRA) has shown to be safe and effective as transfemoral approach (TFA) among unselected ***,very few studies have compared the outcomes between TRA and TFA specifically in patients with a history of coronary artery bypass grafting surgery (CABG).Methods:A total of 404 post-CABG patients who had undergone angiography or PCI were included in the *** primary endpoint was defined as angiographic success and procedure *** secondary endpoint was defined as in-hospital net adverse clinical events (NACEs),which included all cause of death,myocardial infarction (MI),stroke,repeat revascularization,and major *** were followed-up for *** adverse cardiovascular events (MACEs),which included death,MI,and repeat revascularization,at 1-year follow-up were also ***:The angiographic success was reached by 97.4％ in the TRA group compared with 100％ in the TFA group (P =0.02).The procedure success was achieved in 99.1％ in the TRA group and 97.9％ in the TFA group (P =0.68).The incidence rates of in-hospital NACE (2.7％ vs.2.7％,P =1.00) and 1-year MACE (11.5％ vs.12.0％,P =0.88) were similar between TRA and ***,TRA was associated with a lower rate of Bleeding Academic Research Consortium ≥2 bleeding (P =0.02).In patients undergoing graft PCI,the procedure success was similar between TRA and TFA (100.0％ vs.98.7％,P =1.00).The procedure time (25.0 min vs.27.5 min,P =0.53) was also *** significant difference was detected between TRA and TFA in terms of in-hospital NACE (0 vs.0,P =1.00)and 1-year MACE (21.4％ vs.10.3％,P =0.19).Conclusions:Compared with TFA,TRA had lower angiographic success but had a similar procedure success in post-CABG *** was also associated with decreased bleeding and shortened hospital stay.

关键词： Coronary Angioplasty Coronary Artery Bypass Surgery Transfemoral Transradial