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高压叶片泵的现状及其展望

流体传动与控制 2006年第6期 1-6页

作者：马文澄上海丹尼逊液压有限公司上海200020

该文全面叙述了高压叶片泵的发展史及其应用,对现有七种高压叶片泵(圆弧头叶片式、双叶片式、阶梯叶片式、母子叶片式、弹簧叶片式、柱销叶片式、定比减压阀式)分别论述了特征描述、卸载原理、叶片受力分析及主要优缺点。

关键词：液压传动液压泵高压叶片泵结构

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正十四烷层流燃烧特性的实验

航空动力学报 2020年第10期35卷 2036-2045页

作者：刘宇王金铎谷午马洪安曾文沈阳航空航天大学航空发动机学院辽宁省航空推进系统先进测试技术重点实验室沈阳110136

采用定容燃烧实验平台获得初始压力为0.1 MPa、初始温度为420、450 K和480 K,当量比为0.8~1.4工况下正十四烷/空气预混气层流燃烧速度和马克斯坦长度,并分析了初始温度、当量比等因素的影响。研究发现:初始温度和当量比的增加对预混气... 详细信息

采用定容燃烧实验平台获得初始压力为0.1 MPa、初始温度为420、450 K和480 K,当量比为0.8~1.4工况下正十四烷/空气预混气层流燃烧速度和马克斯坦长度,并分析了初始温度、当量比等因素的影响。研究发现:初始温度和当量比的增加对预混气球形火焰稳定性影响较小,在初始温度为480 K、当量比为1.3工况下,火焰内部无裂纹或胞状结构;初始温度的增加能够加快火焰传播速度,促进火焰锋面形成,其影响在稀混合气中更为显著;随着当量比的增加,正十四烷预混燃烧火焰马克斯坦长度减小,火焰稳定性变差;随着初始温度的增加,正十四烷马克斯坦长度减小,无拉伸火焰传播速度和层流燃烧速度增加,另外,与RP-3航空煤油层流燃烧速度对比发现,正十四烷层流燃烧速度整体偏高。

关键词：层流燃烧速度马克斯坦长度正十四烷/空气预混气初始温度当量比

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新型静止无功补偿器稳定系统电压的研究

中国电力 2006年第7期39卷 52-55页

作者：王树文纪延超马文川哈尔滨工业大学黑龙江哈尔滨150001

介绍一种基于PwM技术的新型静止无功补偿器。研究该补偿器在稳定系统电压方面的作用,分别对它在小扰动和大扰动情况下的工作状况进行分析,证明在工作范围内新型静止无功补偿器对系统电压有很大的支撑作用,可有效稳定系统电压。该补偿器... 详细信息

介绍一种基于PwM技术的新型静止无功补偿器。研究该补偿器在稳定系统电压方面的作用,分别对它在小扰动和大扰动情况下的工作状况进行分析,证明在工作范围内新型静止无功补偿器对系统电压有很大的支撑作用,可有效稳定系统电压。该补偿器具有结构简单、控制方便、响应速度快等特点。采用单机无穷大系统对补偿器进行开环和闭环控制仿真研究,验证该补偿器能维持装设点的电压并提高其电压稳定性。

关键词：电力系统电压稳定性静止无功补偿器

Reliability-Based Shape Optimization of Tenon/Mortise in Aero-engines with Contact

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Chinese Journal of Aeronautics 2003年第4期16卷 193-197页

作者：崔海涛马海全温卫东 College of Energy and Power Engineering Nanjing University of Aeronautics and Astronautics Nanjing 210016 China

Based on the theory of reliability-based structural shape optimization, exact expressions of the sensibility using the stochastic finite element method for contact problems were derived in detail, and the basic steps of structural optimization were given. A coattail-type tenon/mortise of an aero-engine was optimized. In this model, the maximum equivalent stress of the nodes on the boundary of the tenon was the objective function; the width of tooth’s neck and the side surface’s slope angle of a tenon were design variables, with constraints of tension stress, extrusion stress and reliability index. The result showed that the distributions of the contact pressure between tenon and mortise, the equivalence stress and reliability index were more reasonable. It validates the correctness of the optimization model and the reliability-based structural shape optimization, and provides valuable references for structural design of the tenon/mortise.

关键词： reliability-based shape optimization contact problem tenon/mortise stochastic finite element

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基于时空共现的移动用户社会关系类型推断

吉林大学学报（工学版） 2019年第2期49卷 584-591页

作者：李志单洪马春来牛钊程静文国防科技大学电子对抗学院合肥230037

针对当前方法推断结果类型受限及准确率较低的问题,以移动用户位置数据为对象,综合利用时空共现区统计数据和语义信息,提出一种新的社会关系类型推断方法。通过用户共现频次、时空共现区位置熵和离散距离3种统计数据计算时空共现强度;... 详细信息

针对当前方法推断结果类型受限及准确率较低的问题,以移动用户位置数据为对象,综合利用时空共现区统计数据和语义信息,提出一种新的社会关系类型推断方法。通过用户共现频次、时空共现区位置熵和离散距离3种统计数据计算时空共现强度;依据时空共现区公共地点和用户个人地点识别结果获取其语义信息。结合时空共现强度和语义信息生成时空共现向量,根据向量特征的类别相关性和冗余信息量,按照"最小相关-最大冗余"原则提取时空共现区语义特征,得到特征向量。针对样本特点和社会关系类型推断需求,选择多分类支持向量机算法构造分类模型。在Foursquare数据集上进行实验验证,结果表明,该方法能有效推断移动用户的家人、同事、朋友和其他4种社会关系类型,准确率高达89.3%,与同类方法相比精确率和召回率分别提高7.9%和6.6%。

关键词：计算机应用技术时空共现社会关系类型位置数据语义信息最小相关-最大冗余

manipulating the ion-transference and deposition kinetics by regulating the surface chemistry of zinc metal anodes for rechargeable zinc-air batteries

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Green Energy & Environment 2023年第1期8卷 318-330页

作者： Miao He Chaozhu Shu Ruixing Zheng wei Xiang Anjun Hu Yu Yan Zhiqun Ran Minglu Li Xiaojuan wen Ting Zeng Jianping Long College of materials and Chemistry&Chemical Engineering Chengdu University of Technology1#DongsanluErxianqiaoChengduSichuan610059China State Key Laboratory of Electronic Thin Films and Integrated Devices University of Electronic Science and Technology of ChinaChengduSichuan610054China

Aqueous zinc-air battery(ZAB)has attractive features as the potential energy storage system such as high safety,low cost and good environmental ***,the issue of dendrite growth on zinc metal anodes has seriously hindered the development of ***,the N-doped carbon cloth(NC)prepared via magnetron sputtering is explored as the substrate to induce the uniform nucleation of zinc metal and suppress dendrite *** show that the introduction of heteroatoms accelerates the migration and deposition kinetics of Zn^(2+)by boosting the desolvation process of Zn^(2+),eventually reducing the nucleation ***,theoretical calculation results confirm the zincophilicity of N-containing functional group(such as pyridine N and pyrrole N),which can guide the nucleation and growth of zinc uniformly on the electrode surface by both promoting the redistribution of Zn^(2+) in the vicinity of the surface and enhancing its interaction with zinc *** a result,the half-cell assembled with magnetron sputtered carbon cloth achieves a high zinc stripping/plating coulombic efficiency of 98.8%and long-term stability of over 500 cycles at 0.2 ma cm^(-2).And the Coulombic efficiency reached about 99.5%at the 10th cycle and maintained for more than 210 cycles at a high current density of 5.0 ma cm^(-2).The assembled symmetrical battery can deliver 220 plating/stripping cycles with ultra-low voltage hysteresis of only 11 *** addition,the assembled zinc-air full battery with NC-Zn anode delivers a high special capacity of about 429 mah g_(Zn)^(-1) and a long life of over 430 *** effectiveness of surface functionalization in promoting the transfer and deposition kinetics of Zn^(2+) presented in this work shows enlightening significance in the development of metal anodes in aqueous electrolytes.

关键词： Zinc metal anodes Dendrite-free Surface chemical regulation Ion-transference kinetics Aqueous zinc-air battery

红树植物落叶碎屑对海水中多环芳烃的吸附作用

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生态学杂志 2008年第5期27卷 858-861页

作者：陆志强郑文教马丽集美大学水产学院厦门大学生命科学学院福建厦门361005 国家海洋局第三海洋研究所福建厦门361005

在实验室条件下,研究了海水中多环芳烃(PAHs)(含低分子量PAHs苊、菲和屈艹以及高分子量PAHs苯并[g,h,i]芘)浓度分别为40、400和4000μg·L-1时,红树植物秋茄(Kandeliacandel)和白骨壤(Avicennia marina)不同分解状态落叶碎屑对PAHs的吸... 详细信息

在实验室条件下,研究了海水中多环芳烃(PAHs)(含低分子量PAHs苊、菲和屈艹以及高分子量PAHs苯并[g,h,i]芘)浓度分别为40、400和4000μg·L-1时,红树植物秋茄(Kandeliacandel)和白骨壤(Avicennia marina)不同分解状态落叶碎屑对PAHs的吸附作用。结果显示:在同等PAHs浓度下,秋茄和白骨壤落叶碎屑对4种PAHs的吸附总量相近,树种间或分解状态间的吸附差异不显著;随着PAHs浓度的增加,2种红树植物落叶碎屑对4种PAHs的吸附率均呈现逐渐增加的趋势;PAHs浓度较低时,落叶碎屑对艹屈和菲有较高的吸附率或选择性吸附,PAHs浓度较高时,落叶碎屑对苯并[g,h,i]芘吸附率提高。上述结果表明,不同分解状态下的红树植物落叶碎屑对海水中PAHs均有较强吸附能力,及时清除落叶碎屑,是去除海水中PAHs的有效途径之一。

关键词：红树植物落叶碎屑多环芳烃吸附

Clinical significance of different periampullary diverticulum classifications for endoscopic retrograde cholangiopancreatography cannulation

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world Journal of Gastroenterology 2020年第19期26卷 2403-2415页

作者： Ping Yue Ke-Xiang Zhu Hai-Ping wang wen-Bo Meng Jian-Kang Liu Lei Zhang Xiao-Liang Zhu Hui Zhang Long Miao Zheng-Feng wang wen-Ce Zhou Azumi Suzuki Kiyohito Tanaka Xun Li Department of Special Minimally Invasive Surgery The First Hospital of Lanzhou UniversityLanzhou 730000Gansu ProvinceChina Key Laboratory of Biological Therapy and Regenerative Medicine Transformation of Gansu Province The First Hospital of Lanzhou UniversityLanzhou 730000Gansu ProvinceChina Hepatopancreatobiliary Surgery Institute of Gansu Province Lanzhou 730000Gansu ProvinceChina The First Clinical Medical School of Lanzhou University Lanzhou 730000Gansu ProvinceChina The Second Department of General Surgery The First Hospital of Lanzhou UniversityLanzhou 730000Gansu ProvinceChina Cardiovascular Division Brigham and Women's HospitalHarvard Medical SchoolBostonMA 02451United States The Fifth Department of General Surgery The First Hospital of Lanzhou UniversityLanzhou 730000Gansu ProvinceChina Department of Gastroenterology Kyoto Second Red Cross HospitalKyoto 602-8026Japan

BACKGROUND Different types of periampullary diverticulum(PAD) may differentially affect the success of endoscopic retrograde cholangiopancreatography(ERCP) cannulation,but the clinical significance of the two current PAD classifications for cannulation is *** To verify the clinical value of our newly proposed PAD *** A new PAD classification(Li-Tanaka classification) was proposed at our *** PAD patients with native papillae who underwent ERCP from January 2012 to December 2017 were classified according to three classification systems, and the effects of various types of PAD on ERCP cannulation were *** A total of 3564 patients with native papillae were enrolled, including 967(27.13%)PAD patients and 2597(72.87%) non-PAD patients. In the Li-Tanaka classification, type Ⅰ PAD patients exhibited the highest difficult cannulation rate(23.1%, P = 0.01), and type Ⅱ and Ⅳ patients had the highest cannulation success rates(99.4% in type Ⅱ and 99.3% in type Ⅳ, P was higher than that in non-PAD patients [odds ratio(OR) = 1.87, 95% confidence interval(CI): 1.04-3037, P = 0.037]. In addition, compared to the non-PAD group,the difficulty of cannulation in the type Ⅰ PAD group according to the Li-Tanaka classification was greater(OR = 2.04, 95%CI: 1.13-3.68, P = 0.004), and the successful cannulation rate was lower(OR = 0.27, 95%CI: 0.11-0.66, P while it was higher in the type Ⅱ PAD group(OR = 4.44, 95%CI: 1.61-12.29, P <0.01).CONCLUSION Among the three PAD classifications, the Li-Tanaka classification has an obvious clinical advantage for ERCP cannulation, and it is helpful for evaluating potentially difficult and successful cannulation cases among different types of PAD patients.

关键词： Endoscopic retrograde cholangiopancreatography Periampullary diverticulum Classification Difficult cannulation Successful cannulation

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船载危险品应急管理系统的设计与实现

大连海事大学学报 2013年第2期39卷 57-59页

作者：杨家轩马文耀史国友大连海事大学航海学院辽宁大连116026 广东海洋大学航海学院广东湛江524025

为对危险品应急事故做出快速反应,实现事故动态监控和实时决策,结合船舶运载危险品的特点,提出船载危险品应急管理系统的设计思路.对船载危险品应急管理系统的关键模块,如化学品查询系统、反应性预测系统和应急决策生成模块设计进行介绍... 详细信息

为对危险品应急事故做出快速反应,实现事故动态监控和实时决策,结合船舶运载危险品的特点,提出船载危险品应急管理系统的设计思路.对船载危险品应急管理系统的关键模块,如化学品查询系统、反应性预测系统和应急决策生成模块设计进行介绍.实际应用表明,该系统对海事危险品管理和运输起到一定的安全保障作用.

关键词：船载危险品应急管理系统设计与实现