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Puerarin decreases hypoxia inducible factor-1 alpha in the hippocampus of vascular dementia rats

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Neural Regeneration Research 2012年第6期7卷 421-425页

作者： Haiqin Wu huqing Wang Bei Zhang Guilian Zhang Ru Zhang Lingfeng Zhang Department of Neurology the Second Affiliated Hospital Medical College of Xi＇an Jiaotong University Xi＇an 710004 Shaanxi Province China

In this study, a rat vascular dementia model was established by permanent bilateral common carotid arterial occlusion. Rats were intraperitoneally injected with puerarin 3 days before modeling, for 45 successive days. Results demonstrated that in treated animals hippocampal structures were clear, nerve cells arranged neatly, and cytoplasm was rich in Nissl bodies. The number of cells positive for hypoxia inducible factor-1 alpha, erythropoietin and endothelial nitric oxide synthase was reduced; and the learning and memory abilities of rats were significantly improved. Our experimental findings indicate that puerarin can significantly improve learning and memory in a vascular dementia model, and that the underlying mechanism may be associated with the regulation of the expression of hypoxia inducible factor-1 alpha.

关键词： puerarin vascular dementia hypoxia-inducible factor-1 alpha erythropoietin endothelial nitric-oxide synthase

A Strain Rate Dependent Constitutive Model for the Lower Silurian Longmaxi Formation Shale in the Fuling Gas Field of the Sichuan Basin,China

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Acta Geologica Sinica(English Edition) 2019年第4期93卷 972-981页

作者： HOU Zhenkun LI Xianwen ZHANG Yanming LIANG huqing GUO Ying CheNG Hanlie GAO Ruchao Guangzhou Institute of Building Science Co. Ltd.Guangzhou 510440China School of Materials Science and Engineering South China University of TechnologyGuangzhou 510640China Oil and Gas Technology Research Institute Changqing Oilfield Branch Company of PetroChinaXi’an 710018China Institute of Geology and Paleontology Linyi UniversityLinyi 276000ShandongChina LandOcean Energy Services Co. Ltd.Beijing 100084China CCCC Second Harbour Engineering Co. Ltd.Wuhan 430040China

Shale,as a kind of brittle rock,often exhibits different nonlinear stress-strain behavior,failure and timedependent behavior under different strain *** capture these features,this work conducted triaxial compression tests under axial strain rates ranging from 5×10-6 s-1 to 1×10-3 *** results show that both elastic modulus and peak strength have a positive correlation relationship with strain *** strain rate-dependent mechanical behaviors of shale are originated from damage growth,which is described by a damage *** axial strain is the same,the damage parameter is positively correlated with strain *** strain rate is the same,with an increase of axial strain,the damage parameter decreases firstly from an initial value(about 0.1 to 0.2),soon reaches its minimum(about 0.1),and then increases to an asymptotic value of *** on the experimental results,taking yield stress as the cut-off point and considering damage variable evolution,a new measure of micro-mechanical strength is *** on the Lemaitre’s equivalent strain assumption and the new measure of micro-mechanical strength,a statistical strain-rate dependent damage constitutive model for shale that couples physically meaningful model parameters was *** back-calculations of these triaxial compression tests results demonstrate the ability of the model to reproduce the primary features of the strain rate dependent mechanical behavior of shale.

关键词： strain rates triaxial compression tests damage variable constitutive model Longmaxi Formation shale

Model test and numerical simulation of a new prefabricated double-row piles retaining system in silty clay ground

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Underground Space 2023年第6期13卷 262-280页

作者： Ruisong Wang Hao Yang Pengpeng Ni Chenyang Zhao Chengchao Guo Huihuan Ma Pu Dong huqing Liang Mengxiong Tang School of Civil Engineering Sun Yat-sen UniversitySouthern Marine Science and Engineering Guangdong Laboratory(Zhuhai)Guangdong Key Laboratory of Oceanic Civil EngineeringGuangdong Research Center for Underground Space Exploitation TechnologyZhuhai 519082China Beijing Urban Rail Transit Construction Engineering Co. LtdBeijing 100088China BeSTDR Infrastucture Hospital Zhumadian 463400China School of Architecture and Civil Engineering Huizhou UniversityHuizhou 516008China Guangzhou Municipal Construction Group Co. LtdGuangzhou 510275China State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan430071China

This paper introduces a new prefabricated recyclable double-row piles retaining system for excavations in silty clay *** model test and numerical simulation are conducted to study the system behavior upon *** horizontal displacement(δ_(h)),Von Mises stress(δ_(M)),strain(ε),ground surface settlement(δ_(v)),and earth pressure are systematically ***,the monitoring data of 13 excavation cases supported by double-row piles retaining system are presented and *** experimental results can basically match the numerical results,and the maximumδ_(M),maximum bending moment(M_(max)),maximum horizontal displacement(δ_(hm))of structural members are all less than the tolerance *** ground surface settlement model of double-row piles retaining system consists of three zones,i.e.,rebound influence zone,primary influence zone and secondary influence *** dhm values are 0.07%–1.42%of the excavation depth(he).The maximum ground surface settlement(δ_(vm))is generally less than *** ratio ofδ_(vm)=δ_(hm)varies between 0.09 and 0.76,with an average value of *** observed earth pressure on the retained side of front pile(paf)is about 0.53–0.57γH below the excavation *** the excavation surface,p_(af)decreases dramatically when getting closer to the ground surface.

关键词： Prefabricated recyclable structure Double-row piles retaining system Physical model test Numerical simulation Deformation

Pistil Development in 2 Types of Flowers of Xanthoceras sorbifolia

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Forestry Studies in China 2004年第4期6卷 13-16页

作者： huqing GaoShumin LiFenglan CollegeofBiologicalSciencesandBiotechnology BeijingForestryUniversityBeijing100083P.R.China

In order to investigate flower development and female abortion during sex differentiation of Xanthoceras sorbifolia, anatomical observations and comparative study on differential proteins were carried out in different developmental stages of two types of flowers of this species. It was found that the selective abortion happened in male flower before the formation of megasporo- cyte. Special proteins related to the female abortion were found through 2-dimensional electrophoretic analysis. Protein A1 (14.2 kD) only existed in florescence of male flower, while B1 (13.7 kD) and B2 (18.2 kD) disappeared in that stage of male flower. They were all considered to be relative to pistil abortion of Xanthoceras sorbifolia.

关键词： Xanthoceras sorbifolia sex differentiation female abortion differential protein

基于神经网络观测器的水下拖体输出反馈姿态控制

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兵工学报 2020年第12期41卷 2504-2513页

作者：井安言佘湖清宜昌测试技术研究所湖北宜昌443003

针对水下拖体俯仰姿态控制系统设计时无法精确建模、模型具有强烈非线性和不确定性以及不可测外界干扰和角速度等问题,设计了一种基于观测器的补偿控制系统。该系统中两个神经网络独立对动态非线性模型进行在线辨识,分别配合状态观测器... 详细信息

针对水下拖体俯仰姿态控制系统设计时无法精确建模、模型具有强烈非线性和不确定性以及不可测外界干扰和角速度等问题,设计了一种基于观测器的补偿控制系统。该系统中两个神经网络独立对动态非线性模型进行在线辨识,分别配合状态观测器和补偿滑模控制器完成对系统状态变量的实时观测与补偿控制。在观测器中加入鲁棒项抑制附加干扰,设计了两种自适应权值更新律以及一种映射修正自适应律以保证系统的稳定性。经Lyapunov理论证明,在满足一定条件下,系统的观测与控制误差均为最终一致有界。仿真和实验结果表明,所设计的补偿控制系统具有良好的自适应性和鲁棒性。

关键词：水下拖体神经网络观测器自适应律补偿控制系统

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添加剂对环丁砜抽提能力的影响

石油化工 2007年第12期36卷 1225-1228页

作者：何伟杰顾毅梅华姚虎卿南京工业大学化学化工学院江苏南京210009 扬子石化股份有限公司江苏南京210048

采用气相色谱法测定环丁砜对甲苯的抽提能力,通过改变温度、甲苯与正己烷的质量比等实验条件,研究了添加剂对环丁砜劣化前后甲苯抽提能力的影响。实验结果表明,在40℃、甲苯和正己烷的质量比为3:1时,不含添加剂的环丁砜的抽提能力降低了... 详细信息

采用气相色谱法测定环丁砜对甲苯的抽提能力,通过改变温度、甲苯与正己烷的质量比等实验条件,研究了添加剂对环丁砜劣化前后甲苯抽提能力的影响。实验结果表明,在40℃、甲苯和正己烷的质量比为3:1时,不含添加剂的环丁砜的抽提能力降低了23.2%,而含添加剂的环丁砜的抽提能力仅降低了0.8%,含添加剂的环丁砜3次劣化后的抽提能力降低了1.5%。劣化前,加入添加剂对环丁砜抽提甲苯的能力基本没有影响;劣化后,不含添加剂的环丁砜的抽提能力大幅度下降,而含添加剂的环丁砜的抽提能力变化不大,且含添加剂的环丁砜3次劣化后其抽提能力没有明显下降。

关键词：环丁砜芳烃抽提性能添加剂劣化

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旁泄间隙对燃气弹射内弹道特性影响

航空动力学报 2023年第10期38卷 2407-2414页

作者：赵加鹏张磊佘湖清郭晋兵中国船舶集团有限公司第七一〇研究所湖北宜昌443003

为了研究旁泄间隙(发射筒与隔板的间隙)对燃气弹射内外流场及内弹道特性参数的影响,采用Realizableκ-ε湍流模型,结合动态分层动网格及用户自定义函数(user defined function,UDF)技术,对燃气弹射过程进行了数值模拟,分析了旁泄间隙大... 详细信息

为了研究旁泄间隙(发射筒与隔板的间隙)对燃气弹射内外流场及内弹道特性参数的影响,采用Realizableκ-ε湍流模型,结合动态分层动网格及用户自定义函数(user defined function,UDF)技术,对燃气弹射过程进行了数值模拟,分析了旁泄间隙大小对燃气弹射性能的影响,并进行了地面发射试验。通过与试验数据对比,验证了燃气弹射仿真模型的有效性。仿真结果表明,在旁泄间隙出口附近形成明显漩涡,旁泄间隙的增大会导致低压室压力与加速度峰值减小,并使试验弹出筒时间延长、出筒速度降低,但变化趋势呈现非线性特征。旁泄间隙从2 mm增大到6 mm时,出筒时间延长7.7%,出筒速度降低16.3%,可认为在此范围内旁泄间隙的影响幅度相对较小;但此后旁泄间隙的影响会显著增强,当旁泄间隙从6 mm增大到8 mm时,出筒时间延长20%,出筒速度降低35.8%,当旁泄间隙增大到10 mm时,试验弹到筒口速度甚至降为0 m/s。本文研究结果为燃气弹射装置的设计与优化提供参考借鉴。

关键词：燃气弹射旁泄间隙内外流场动态分层技术内弹道

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Increased hypoxia-inducible factor 1alpha expression in rat brain tissues in response to aging

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Neural Regeneration Research 2012年第10期7卷 778-782页

作者： huqing Wang Haiqin Wu hena Guo Guilian Zhang Ru Zhang Shuqin Zhan Department of Neurology Second Affiliated Hospital of Medical College Xi＇an Jiaotong University Xi＇an 710004 Shaanxi Province China

The present study observed changes in rat neural cells at various ages （3, 18, 24, and 30 months）. With age, neural cells became large and were sparsely arranged, and the number of Nissl bodies decreased. In addition, hypoxia-inducible factor 1α expression increased with increasing age in hippocampal CA1 and CA3 regions, motor cortex, and the first subfolium, especially from 3 to 18 months. In the open-field test, grid crossing decreased with increasing age, especially from 18 months. The number of rearings reached a peak in the 18 months group, and then subsequently decreased. The results suggested that hypoxia-inducible factor 1α played an important role in the nervous system aging process.

关键词： aging brain hypoxia-inducible factor 1α Nissl body behavior

基于多种群差分进化算法的火箭弹自力弹射多目标约束优化设计

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航空动力学报 2023年第6期38卷 1516-1524页

作者：宋健李超佘湖清蔡蒨中国船舶集团有限公司宜昌测试技术研究所湖北宜昌443000

针对火箭弹自力弹射设计中降低低压室压强峰值与提高弹体出筒速度之间的矛盾,开展自力弹射的优化设计工作。建立自力弹射发动机-低压室耦合内弹道求解模型,并开展两种工况共4发实弹的验证试验;提出融合多种差分策略的多种群差分进化算法... 详细信息

针对火箭弹自力弹射设计中降低低压室压强峰值与提高弹体出筒速度之间的矛盾,开展自力弹射的优化设计工作。建立自力弹射发动机-低压室耦合内弹道求解模型,并开展两种工况共4发实弹的验证试验;提出融合多种差分策略的多种群差分进化算法,并采用“剔除-补足”操作处理优化过程中的约束条件;考虑自力弹射的实际设计约束,以低压室压强峰值和弹体出筒速度为目标建立两目标约束优化模型,并采用多种群差分进化算法进行优化计算。结果表明:计算得到的Pareto前沿近似呈斜率不同的两段线性区间,随低压室压强峰值增大,相同压强增幅带来的出筒速度增量减小;在Pareto前沿上均匀选取12个优化方案并采用逼近理想解排序法进行排序,排序后得到的最终优化方案的低压室压强峰值降低16.11%,弹体出筒速度增加54.55%,自力弹射性能得到提升。

关键词：火箭弹自力弹射内弹道模型多目标约束优化差分进化逼近理想解排序法(TOPSIS)

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