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The Infiltration Process and Texture Transition of 2D C/C Composites

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Journal of Materials Science & Technology 2009年第1期25卷 109-114页

作者： Hejun li Guozhong Xu Kezhi li Chuang wang wei li Miaoling li Carbon/carbon Composites Research Center Key Laboratory of Ultrahigh Temperature Composites Northwestern Polytechnical University Xi＇an 710072 China

2D needle-punched fiber felt was infiltrated by a kind of rapid isothermal chemical vapor infiltration technique. The infiltration process and texture transition of the infiltrated C/C composites were investigated. The porosity and the variations of the cumulative pore volume were determined by mercury porosimetry. The texture of matrix carbon was studied under a polarized light microscope. The results show that the relative mass gain of the sample increases directly as the infiltration time at the initial stage until 20 h, and subsequently the increasing rate of the relative mass gain decreases gradually with the prolonging of infiltration time. Three layers of pyrocarbon were formed around fibers. Low-textured pyrocarbon was obtained at the initial stage. With the densification going on, high-textured pyrocarbon was formed on the surface of low-textured pyrocarbon. Then, low-textured pyrocarbon was produced again during the final stage of densification. The texture transition is ascribed to the variation of the ratio of cumulative inner surface area to volume of pores and the gas partial pressure in pores.

关键词： C/C composites Isothermal chemical vapor infiltration (ICVI) Pyrocarbon Mercury porosimetry Polarized light microscope

基于急救效率、溶栓成功率分析胸痛中心建设对AMI的应用价值

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心血管康复医学杂志 2024年第4期33卷 481-485页

作者：王越越王镨王丽伟廊坊市第四人民医院急诊科河北廊坊065700 廊坊市第四人民医院心内科河北廊坊065700 廊坊市第四人民医院重症医学科河北廊坊065700

目的:探究胸痛中心建设对急性心肌梗死(AMI)患者的抢救效果及应用价值。方法:筛选本院2020年3月至2021年3月收治的144例AMI患者进行研究,依据双盲法分为传统急救组(予以传统急救流程干预)及胸痛中心组(胸痛中心建设干预),每组72例。比... 详细信息

目的:探究胸痛中心建设对急性心肌梗死(AMI)患者的抢救效果及应用价值。方法:筛选本院2020年3月至2021年3月收治的144例AMI患者进行研究,依据双盲法分为传统急救组(予以传统急救流程干预)及胸痛中心组(胸痛中心建设干预),每组72例。比较两组医护人员综合急救能力[采用迷你临床演练评估量表(Mini-CEX)评估]、急救效率、溶栓情况、死亡率、1年内再住院率及不良心血管事件发生率。结果:与传统急救组比较,胸痛中心组Mini-CEX评分[(5.17±1.09)分比(7.41±1.27)分]显著更高,发病至首次医疗接触时间[(12.40±1.93)min比(5.51±0.76)min]、入门至血管开通时间[(114.37±26.06)min比(67.05±8.34)min]、首次医疗接触至血管开通时间[(104.63±3.30)min比(79.72±2.73)min]、入院至溶栓时间[(68.08±2.17)min比(52.84±1.58)min]、卧床时间[(65.27±2.02)h比(41.67±1.77)h]均显著减少,死亡率(11.11%比2.78%)、1年内再住院率(15.28%比4.17%)及不良心血管事件发生率(18.06%比5.56%)均显著降低(P<0.05或<0.01)。结论:胸痛中心建设可以显著提升医护人员的综合素质,完善急救流程,进一步提升AMI患者的急救效率,具有较高的临床推广价值。

关键词：心肌梗死胸痛急救医疗服务

基于卷积注意力机制的锂离子电池剩余使用寿命预测研究

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西南民族大学学报（自然科学版） 2024年第3期50卷 336-346页

作者：史云汪立伟公岷西南民族大学电子信息学院四川成都610041

锂离子电池剩余使用寿命的准确估计和预测对于锂离子电池电源管理系统有着重要的意义.一方面能够提高实际电路系统的可靠性,同时能够延长电池的使用寿命.锂离子电池的退化过程表现出复杂、非线性特征且伴随容量再生现象,导致传统预测模... 详细信息

锂离子电池剩余使用寿命的准确估计和预测对于锂离子电池电源管理系统有着重要的意义.一方面能够提高实际电路系统的可靠性,同时能够延长电池的使用寿命.锂离子电池的退化过程表现出复杂、非线性特征且伴随容量再生现象,导致传统预测模型对锂离子电池剩余使用寿命预测(Remaining Useful life,RUL)准确性低.为进一步提升锂离子电池RUL的预测精度,首先深入分析电池历史退化数据,构建一种新的基于卷积注意力机制深度学习框架.通过对锂离子电池老化循环过程的研究,选取容量数据作为健康因子(Health Indicator,HI),利用卷积神经网络(Convolu⁃tional Neural Network,CNN)的卷积和池化操作挖掘数据内在信息,降低数据复杂度,提取电池数据的时序特征.并将特征数据输出到构建的注意力机制(Attention Mechanism,AM)深度网络,捕捉全局时序数据的位置信息和分析时序数据中内部信息的关系,以此获得准确的RUL预测.最后使用公开的NASA和CALCE数据集上进行验证,并对比其他几种预测模型,结果表明所提出模型的具有较高预测精度和泛化适应能力.

关键词：锂电池剩余使用寿命健康因子卷积注意力机制注意力神经网络

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Microstructure and kinetics of hot deformation WE43 magnesium alloy

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Rare Metals 2008年第4期27卷 405-409页

作者： GAO Jiacheng wang Qiang wang Yong li wei NIU Wenjuan College of Materials Science and Engineering National Engineering Research Center for Magnesium Alloys Chongqing University Chongqing 400044 China

The effect of compression on the microstructures and flow behavior of WE43 magnesium alloy was investigated in this article. The relationship between flow stress and strain rate was discussed. According to the empirical formula ε = Aδ^n exp （-Q/R T）, the value of heat activation of WE43 magnesium alloys is 297,15 kJ/mol. A mechanism of deformation softening of WE43 alloy in testing hot deformation was identified to be dynamic recrystallization.

关键词： WE43 magnesium alloy hot deformation microstructure kinetics

Effect of Slope Degree on the Lateral Bending in Gekko geckos

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Journal of Bionic Engineering 2015年第2期12卷 238-249页

作者： Zhouyi wang Lei Cai wei li Aihong Ji Wenbo wang Zhendong Dai Institute of Bio-Inspired Structure and Surface Engineering Nanjing University of Aeronautics and Astronautics Nanjing 210016 China

A gecko＇s habitat possesses a wide range of climbing slopes that pose a number of postural challenges for climbing lo- comotion. Few studies have examined the relationship between the lateral bending of the trunk of a gecko and other aspects of locomotion when climbing. In this paper, three-dimensional reaction forces and high-speed videos of Gekko geckos moving on different slopes are used to reveal how the lateral bending of the animal＇s trunk responds to changing slopes. The results of such observations indicate that the minimum bending radius continually decreases with an increase in the slope, illustrating that the degree of bending of the trunk becomes significantly greater. Moreover, a lateral bending mechanical model is used to show the interrelation between the lateral bending in the frontal plane and the sagittal deformation of the trunk caused by gravity. Taken together, these results have advanced our understanding of the role of lateral bending of vertebrates when climbing on a slope.

关键词： slope lateral bending reaction force gecko ceiling

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大型人工湿地绿藻的产生及控制研究

价值工程 2024年第24期43卷 110-112页

作者：王洋王立伟佘治涛刘伟苏天宇山东电力建设第三工程有限公司青岛266100 青岛华丰伟业电力科技工程有限公司青岛266100

人工湿地作为一种生态友好型的污水处理技术,因其高效、经济和环境可持续性而受到广泛关注。然而,人工湿地中的绿藻问题也不容忽视,它们的生长不仅影响水质,还可能破坏湿地生态系统的平衡。本文通过对沙特某人工湿地项目绿藻的控制进行... 详细信息

人工湿地作为一种生态友好型的污水处理技术,因其高效、经济和环境可持续性而受到广泛关注。然而,人工湿地中的绿藻问题也不容忽视,它们的生长不仅影响水质,还可能破坏湿地生态系统的平衡。本文通过对沙特某人工湿地项目绿藻的控制进行描述,主要针对潜流床“人工湿地”项目对绿藻容易产生的地点、产生原因和危害进行分析,并提出了对应的控制措施,来降低绿藻,提高人工湿地处理污水的效果。

关键词：人工湿地绿藻水位控制水量控制

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Acupuncture at the San Jiao meridian affects brain stem tissue G protein content in a rat migraine model

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Neural Regeneration Research 2008年第9期3卷 958-961页

作者： Sue wang wei li Guangwei Zhong Zhenyan li lingbo Wen Institute of Integrated Traditional Chinese and Westem Medicine Xiangya Hospital Central South University Changsha 410008 HunanProvince China

BACKGROUND： G protein is closely associated with vasomotion. Vasomotor dysfunction accompanies migraine attack. OBJECTIVE： To investigate the effects of the San Jiao meridian acupuncture on G protein content in a rat migraine model. DESIGN, TIME AND SETTING： The present randomized grouping, cellular and molecular biological level trial was performed at the Institute of Integrated Traditional Chinese and Western Medicine, Xiangya Hospital, Central South University ＆ Key Laboratory for Tumor Proteomics of Ministry of Health between October 2003 and June 2004. MATERIALS： Forty healthy, male, Sprague Dawtey rats were included in this study. The G6805-2A electro-acupuncture apparatus was a product of Shanghai Huayi Medical Instrument Factory, China. Nitroglycerin was produced by Guangzhou Mingxing Pharmaceutical Factory, China. Antibodies against inhibitory and stimulatory G proteins were purchased from Sigma Chemical Company, USA. METHODS： All 40 rats were randomly and evenly divided into 4 groups. In the blank control group, the rats remained untouched. Rats from the normal control group were subcutaneously administered 2 mL/kg physiological saline. In the model group, migraine was induced with a subcutaneous injection of 10 mg/kg nitroglycerin （5 g/L）, and the rats received no further treatment. In the acupuncture-treated group, 30 minutes after migraine induction, acupuncture was performed at the bilateral Waiguan （SJ 5） and Yifeng （SJ 17） points, with an acupuncture depth of 1 mm. Electric-stimulation parameters of 20 Hz for low frequency, 40 Hz for high frequency, and 0.5-1.0 mA for current intensity were set. Ten acupuncture sessions were applied, with 20-minute low-frequency and 20-minute high-frequency stimulation and 3 seconds of interval time. MAIN OUTCOME MEASURES： Inhibitory and stimulatory G protein contents were detected by Western blot analysis. RESULTS： At 4 hours after migraine induction, compared with the blank control and normal control groups stimula

关键词： acupuncture G protein: migraine San Jiao meridian Western blot

Interference Angle on Quantum Rotational Energy Transfer in Na+Na_2 (A^1Σ_u^+,v = 8～b^3Π_(Ou), v = 14) Molecular Collision System

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Communications in Theoretical Physics 2009年第12期52卷 1062-1066页

作者： wang wei-li MIAO Gang li Jian MA Feng-Cai Department of Basic Course Liaoning Technical University Huludao 125105 China Department of Science Shenyang Institute of Aeronautical Engineering Shenyang 110031 China Department of Physics Liaoning University Shenyang 110036 China

In order to study the collisional quantum interference （CQI） on rotational energy transfer in atom-diatom system, we have studied the relation of the integral interference angle and differential interference angle in Naq-Na2 （A1 ∑u^＋,v=8-b^3∏0u,v=14） collision system. In this paper, based on the first-Born approximation of timedependent perturbation theory and taking into accounts the anisotropic effect of Lennard-Jones interaction potentials, we present a theoretical model of collisional quantum interference in intramolecular rotational energy transfer, and a relationship between differential and integral interference angles.

关键词： rotation energy transfer integral interference angle differential interference angle collision diameter

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大型制冷站调试中的关键问题及解决方案

价值工程 2024年第25期43卷 84-86页

作者：王立伟张军王洋鲁克学周卫东山东电力建设第三工程公司青岛266100

制冷站是现代工业生产中不可或缺的设备之一,其主要设备制冷机压缩机采用磁浮轴承进行压缩气态氟利昂,具有高效、节能、安全等优点。本文主要围绕沙特红海公共事业和基础设施PPP项目制冷站调试过程中遇到的关键问题展开研究,并提出相应... 详细信息

制冷站是现代工业生产中不可或缺的设备之一,其主要设备制冷机压缩机采用磁浮轴承进行压缩气态氟利昂,具有高效、节能、安全等优点。本文主要围绕沙特红海公共事业和基础设施PPP项目制冷站调试过程中遇到的关键问题展开研究,并提出相应的解决方案。通过对实际案例分析,总结了制冷站调试过程中的典型问题及其解决方法,旨在为制冷站调试工程师提供参考和借鉴。

关键词：制冷站制冷机磁浮轴承调试问题解决方案