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Seismic stability safety evaluation of gravity dam with shear strength reduction method

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Water Science and Engineering 2009年第2期2卷 52-60页

作者： Da-sheng WANG Liao-jun ZHANG Jian-jun XU ming-jie he Wei-di ZHANG East China Investigation ＆ Design Institute Hangzhou 310014 P. R. China College of Water Conservancy and Hydropower Engineering Hohai University Nanjing 210098 P. R. China

A new method of numerical seismic stability safety evaluation for a rock slope is proposed based on the analysis of a gravity dam foundation subjected to earthquake loading. The shear strengths of the weak discontinuities are divided by different shear strength reduction ratios （K） and numerical seismic analysis is carried out after the static analysis is completed. With different K values, the curves of the permanent horizontal displacement of key points of the dam foundation （K-displacement curves） are studied. According to the curve change, the distribution of plastic zones in the foundation, and the slow convergence of the finite element method （FEM）, the seismic stability safety factor is defined as Kwhen the gravity dam is in the limit equilibrium state subjected to earthquake loading. These concepts were applied to the evaluation of seismic stability safety of a gravity dam for a hydropower project. The analysis of the example shows that the proposed method is feasible and is an effective method of seismic stability safety evaluation.

关键词： dynamic stability shear strength reduction ratio, gravity dam permanent horizontaldisplacement ADINA system

基于测地线距离的核主元分析在齿轮泵故障识别中应用

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上海交通大学学报 2011年第11期45卷 1632-1636页

作者：杨庆陈桂明刘鲭洁何庆飞第二炮兵工程学院装备管理工程系西安710025

针对传统的高斯径向基核函数中采用欧氏距离计算方法难以完全反映非线性振动数据样本点与点之间位置关系的问题,提出了改进的核主元分析方法.在高斯径向基核函数中使用测地线距离代替欧氏距离,建立基于样本类内散度和类间距的评价函数,... 详细信息

针对传统的高斯径向基核函数中采用欧氏距离计算方法难以完全反映非线性振动数据样本点与点之间位置关系的问题,提出了改进的核主元分析方法.在高斯径向基核函数中使用测地线距离代替欧氏距离,建立基于样本类内散度和类间距的评价函数,运用遗传算法优化测地线距离中邻近点参数k以及高斯径向基核函数中参数σ.对采集的齿轮泵不同状态的振动数据进行经验模态分解,从分解的各阶本征模态分量和残余分量中提取10个无量纲参数构成原始特征参数集;运用优化后的核函数对原始特征参数集进行核主元分析.实验结果表明,改进的核主元分析方法取得了较好的识别效果.

关键词：核主元分析高斯径向基核函数测地线距离遗传算法状态识别

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第3代口服头孢菌素——头孢泊肟酯

中国新药与临床杂志 2004年第11期23卷 746-750页

作者：邵长周瞿介明何礼贤复旦大学附属中山医院呼吸科上海200032

头孢泊肟酯口服后在肠壁水解成头孢泊肟经肠道吸收。头孢泊肟有广谱而强大的抗菌作用 ,组织分布广泛 ,T1/2 较长 ,对 β内酰胺酶稳定 ,耐受性良好 ,具有治疗剂量小 ,每日给药次数少的优点。本文主要对其抗菌活性、人体药动学、临床应用... 详细信息

头孢泊肟酯口服后在肠壁水解成头孢泊肟经肠道吸收。头孢泊肟有广谱而强大的抗菌作用 ,组织分布广泛 ,T1/2 较长 ,对 β内酰胺酶稳定 ,耐受性良好 ,具有治疗剂量小 ,每日给药次数少的优点。本文主要对其抗菌活性、人体药动学、临床应用作一综述。

关键词：头孢菌素类抗感染药药理学药物疗法头孢泊肟酯

渤海、黄海沿岸几种经济贝类及其生存环境中的异养细菌

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海洋学报 2002年第2期24卷 101-106页

作者：林凤翱卞正和关春江冯志权马明辉贺杰张映国家海洋环境监测中心辽宁大连116023

报道渤海、黄海6个重点沿岸海域（吕四、青岛、北戴河、盘锦、大连、庄河）海水和沉积物及经济贝类样品中的异养细菌总数检测结果.结果表明,整个渤海、黄海沿岸海域经济贝类体内异养细菌总数的变化范围为2.0×10^（3）～1.6×10^（6）cf... 详细信息

报道渤海、黄海6个重点沿岸海域（吕四、青岛、北戴河、盘锦、大连、庄河）海水和沉积物及经济贝类样品中的异养细菌总数检测结果.结果表明,整个渤海、黄海沿岸海域经济贝类体内异养细菌总数的变化范围为2.0×10^（3）～1.6×10^（6）cfu/g湿重,平均值为2.7×10^（5）cfu/g湿重,其中异养细菌总数最高的样品是在吕四沿岸3号站采集的四角蛤蜊（1.6×10^（6）cfu/g湿重）,其次分别在北戴河沿岸2号站采集的杂色蛤（1.2×10^（6）cfu/g湿重）和毛蚶（1.1×10^（6）cfu/g湿重）,而异养细菌总数最低样品是在青岛沿岸采集的镜蛤（2.0×10^（3）cfu/g湿重）和在大连沿岸采集的太平洋牡蛎、紫贻贝和皱纹盘鲍（≤5.0×10^（3）cfu/g湿重）.该海区表层海水中异养细菌总数变化范围为2.5×10^（5）～1.0×10^（8）cfu/dm^（3）,全海域平均值为1.2×10^（7）cfu/dm^（3）.表层沉积物中异养细菌数量变化范围为2.8×10^（3）～7.5×10^（5）cfu/g干重,全海域平均值为1.3×10^（5）cfu/g干重.根据上述结果和欧共体委员会（93/51/EEC）指令要求,对各海区贝类卫生质量进行了初步评价.这在国内尚属首次.

关键词：渤海黄海异养细菌卫生质量经济贝类生存环境海水沉积物

Optimized Protection Strategies for HVDC Grid with Fault-blocking Modular Multilevel Converters for Overhead Line Applications

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Journal of Modern Power Systems and Clean Energy 2020年第6期8卷 1168-1177页

作者： Sheng Yan Zhiyuan he jie Yang ming Kong Minqiang Hu Southeast University NanjingChina Global Energy Interconnection Research Institute BeijingChina

The high-voltage direct current(HVDC)grid has been recognized as an effective solution for renewable energy ***,two main development trends for HVDC grids are being studied:a DC breaker based HVDC grid and fault-blocking converter based HVDC *** the former has a perfect performance for fault clearance,its development is still highly constrained by the cost and maturity of DC *** latter can extinguish DC faults by the fault-blocking *** using DC breakers,there is no bottleneck in its technical ***,in fault scenarios,such types of HVDC grids will be blocked at length for air-deionization,which is its main *** aim of this paper is to minimize its power interruption time,by optimizing protection coordination *** cover the most complex cases,the overhead line applications,in which the reclosure actions are required to be implemented,are *** this paper,the protection requirements of HVDC grids are first discussed,then the benefits of fault-blocking modular multilevel converters(MMCs)and their fault features are *** on this,a control function is designed to reduce the air-deionization *** minimize the influence of the DC faults,a separation methodology for restarting the system is *** effectiveness of the proposed protection coordination schemes is validated by PSCAD/EMTDC simulations.

关键词： Modular multilevel converter(MMC) high-voltage direct current(HVDC) overhead line fault-blocking converter protection coordination

头孢克洛治疗慢性阻塞性肺疾病继发下呼吸道感染(英文)

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中国新药与临床杂志 2002年第1期21卷 1-4页

作者：瞿介明何礼贤邓伟吾复旦大学附属中山医院肺科上海200032 上海第二医科大学附属瑞金医院肺科上海200025

目的 :评估头孢克洛治疗轻、中度慢性阻塞性肺疾病 (COPD)继发下呼吸道感染的临床疗效和安全性。方法 :对 180例COPD病人 (男性 118例 ,女性 6 2例 ,年龄 6 4a±s 15a)并发下呼吸道感染进行多中心开放试验。口服头孢克洛 2 5 0mg ,tid ,... 详细信息

目的 :评估头孢克洛治疗轻、中度慢性阻塞性肺疾病 (COPD)继发下呼吸道感染的临床疗效和安全性。方法 :对 180例COPD病人 (男性 118例 ,女性 6 2例 ,年龄 6 4a±s 15a)并发下呼吸道感染进行多中心开放试验。口服头孢克洛 2 5 0mg ,tid ,以7～ 14d为一个疗程。结果 :临床总有效率 91.1%(16 4 /180 )。 180例咳痰培养分离到 92株病原菌。头孢克洛对全部分离的细菌的敏感性和清除率分别为 70 %和 6 8% ,头孢克洛对其抗菌谱覆盖细菌的敏感性和清除率分别为 97%和 94 %。不良反应发生率为 3.9% (7/180 )。结论 :头孢克洛仍是十分有效、安全的治疗COPD继发轻。

关键词：慢性阻塞性肺疾病头孢克洛治疗下呼吸道感染

Friedmann Cosmology with a Generalized Equation of State and Bulk Viscosity

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Communications in Theoretical Physics 2007年第2期47卷 379-384页

作者： MENG Xin-he REN jie HU ming-Guang Department of Physics Nankai University Tianjin 300071 China

The universe content is considered as a non-perfect fluid with bulk viscosity and is described by a more general equation of state （endowed some deviation from the conventionally assumed cosmic perfect fluid model）. We assume the bulk viscosityis a linear combination of two terms： one is constant, and the other is proportional to the scalar expansion 0 = 3a/a. The equation of state is described as p = （γ - 1）p ＋ po, where po is a parameter. In this framework we demonstrate that this model can be used to explain the dark energy dominated universe, and different proper choices of the parameters may lead to three kinds of fates of the cosmological evolution： no future singularity, big rip, or Type-Ⅲ singularity as presented in IS. Nojiri, S.D. Odintsov, and S. Tsujikawa, Phys. Rev. D 71 （2005） 063004].

关键词： Friedmann cosmology equation of state bulk viscosity dark energy

Deciphering of advantageous electrocatalytic water oxidation behavior of metal-organic framework in alkaline media

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Nano Research 2021年第12期14卷 4680-4688页

作者： ming Liu Lingjun Kong Xuemin Wang jie he Jijie Zhang Jian Zhu Xian-he Bu School of Materials Science and Engineering National Institute for Advanced MaterialsTKL of Metal and Molecule Based Material ChemistryNankai UniversityTianjin300350China Key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education) College of ChemistryNankai UniversityTianjin300071China

Carboxylic acid-based metal-organic frameworks(MOFs)are normally passed for the“pre-catalysts”for oxygen evolution reaction(OER)due to the hydroxides constructed in-situ during its alkaline hydrolysis process(AHP)in ***,it remains a mystery that they show advantageous activity over prototypical hydroxides when they are directly acted as OER ***,we propose for the first time that the steric hindrance effect of Nafion can induce enhanced catalytic activity of such *** from conventional catalysts without AHP,the Nafion with 3D structure weakens the AHP of Co-MOF nanoribbons,thus forming small size and low crystallinity species(cobalt hydroxide)with more active *** the existence of Nafion also optimizes its electronic structure,which is confirmed by transmission electron microscopy(TEM),in-situ UV absorption spectra,in-situ Raman spectroscopy and so *** with Co-MOF-K obtained by directly immersing the Co-MOF nanoribbons in 1.0 M KOH,the Co-MOF-NK obtained by AHP of Co-MOF mixed with Nafion shows better catalytic *** on the above inspiration,we realized the low overpotential of 268 mV at 10 mA·cm^(−2) by preparing *** work provides a new understanding of the structural reconstruction of MOFs in the field of electrocatalysis.

关键词： metal-organic frameworks structural reconstruction Nafion stereo hindrance water oxidation

Constructing bifunctional Co/MoC@N-C catalyst via an in-situ encapsulation strategy for efficient oxygen electrocatalysis

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Journal of Energy Chemistry 2021年第8期30卷 538-546,I0011页

作者： Hui Huang Lingjun Kong ming Liu jie he Wei Shuang Yunhua Xu Xian-he Bu School of Materials Science and Engineering National Institute for Advanced MaterialsTKL of Metal and Molecule Based Material ChemistryNankai University300071 TianjinChina School of Materials Science and Engineering Key Laboratory of Advanced Ceramics and Machining Technology(Ministry of Education)and Tianjin Key Laboratory of Composite and Functional MaterialsTianjin University300072 TianjinChina Key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education) College of ChemistryNankai University300071 TianjinChina

The large-scale application of Zn-air battery requires the development of efficient,low-cost,and stable bifunctional electrocatalysts for the oxygen evolution reaction(OER)and oxygen reduction reaction(ORR).herein,an electrocatalyst of a Co/Mo C-nanoparticles embedded N-doped carbon(Co/Mo C@N-C)was prepared via the in-situ encapsulation of Co_(2)(CO)_(8)and Mo(CO)6 in ZIF-8 using ball-milling,followed by pyrolysis under an Ar *** used as a bifunctional electrocatalyst,the as-prepared Co/Mo C@N-C showed an ORR half-wave potential of 0.824 V in an alkaline medium and an overpotential of only 290 m V for the OER at 10 m A cm^(-2),which was 70 m V lower than Ru O_(2).The Co/Mo C@N-C was also evaluated as a cathode in a solid-state Zn-air battery and delivered a higher peak discharge power density and better cycling stability(over 1600 min)than Pt/C-Ru O_(2).Most importantly,our work provides a new strategy to prepare bifunctional catalysts and promotes their applications in the energy conversion field.

关键词： In-situ ZIF-8 Bifunctional electrocatalyst New strategy