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Flow variability along a vegetated natural stream under various sediment transport rates

Journal of Mountain Science 2018年第11期15卷 2347-2364页

作者： wang hai-zhou Xu Ze-xing Yu hai-ti wang Xie-kang State Key Laboratory of Hydraulics and Mountain River Engineering Sichuan University

The influence of vegetation and sediment on flow characteristics in open channels cannot be neglected. To study the flow variability under the effects of the instream natural vegetation and sediment supply, experiments were conducted with varied water and sediment supply in a movable bed of a river prototype. The instantaneous threedimensional velocities near two types of vegetation patches(the shrub and the weed) and along the centerline of the main channel with vegetation belts were measured using a 3-D side-looking acoustic Doppler velocimetry. The experimental results show that both the instream vegetation and sediment supply strongly affect the flow and turbulence characteristics. In the case of vegetation patches, both the shrub and weed have a considerable influence on the distribution of the streamwise velocity and turbulence intensity of their surrounding water. The streamwise velocity distribution followed as J-shape and linear shape around the weed and shrub under different experimental conditions. The turbulence intensity was large at the top of the weed and shrub;the shrub had its greatest influence on the downstream water flow. In the case of vegetation belts,the streamwise velocity along the centerline of the main channel exhibited an S-shape, J-shape and linear shape at different locations under varied water,vegetation structures and riverbed *** turbulence intensity along the centerline of the main channel ranged from 0.0 to 0.1. The upstream turbulence intensity was affected considerably by a sediment supply, while the downstream turbulence intensity changed with the varied vegetation characteristics and riverbed topography. The second flow coefficient M-value increased longitudinally and was almost positive along the centerline of the main channel, implying that the rotational direction of the secondary current cell was clockwise.

关键词： Natural vegetation Sediment supply Velocity profile Turbulence intensity Secondary flow Movable bed

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Synthesis and curing of a novel amino-containing phthalonitrile derivative

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Chinese Chemical Letters 2007年第5期18卷 523-526页

作者： Ke Zeng Ke zhou Wen Rui Tang Yan Tang Hong Fei zhou Tao Liu Yi Peng wang hai Bing zhou Gang Yang State Key Laboratory of Polymer Materials Engineering College of Polymer Science and Engineering Sichuan University Chengdu 610065 China

A novel phthalonitrile derivative containing an amino group, 3,5-bis（3,4-dicyanophenoxy）aniline （CPA）, was synthesized via a nucleophilic displacement of 4-nitrophthalonitrile and 5-aminoresorcinol hydrochloride. The structure of CPA was confirmed by Fourier transform infrared spectra （FT-IR） and nuclear magnetic resonance （^1H NMR）. Thermal analysis performed on CPA revealed that the novel phthalonitrile derivative showed a self-promotion curing behavior and the resulting polymer exhibited outstanding heat-resistance.

关键词： Phthalonitrfle derivative Amino group Self-promotion curing behavior

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Increased expression of insulin-like growth factor-binding protein-3 is implicated in erectile dysfunction in two-kidney one-clip hypertensive rats after propranolol treatment

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Asian Journal of Andrology 2011年第6期13卷 851-855页

作者： Zhang-Yan zhou Zhong-Hua Yang Xing-Huan wang Hong Cao Dong Chen Yong-Zhi wang hai-Hong zhou Mou Peng Quan-Liang Liu Shao-Ping Wan Department of Urology Zhongnan Hospital of Wuhan University Wuhan 430071 China

This study aimed to investigate the role of insulin-like growth factor-binding protein-3 （IGFBP-3） in erectUe dysfunction （ED） in two-kidney one-clip （2K-1C） hypertensive rats treated with the β-blocking agent propranolol. Adult male Wistar rats were randomly divided into three groups： a normal control group, a hypertensive control group and a propranolol treatment group （n=9）. After 4 weeks of propranolol treatment, intracavemous pressure （ICP） responses to electrical stimulation of the cavernous nerves were evaluated. The expression of IGFBP-3 and insulin-like growth factor-1 （IGF-1） mRNA and protein in the rat cavernous tissue were detected by quantitative real-time PCR and Western blot, respectively. The concentration of cyclic guanosine monophosphate （cGMP） in the cavernous tissue was determined by enzyme-linked immunosorbent assay （ELISA）. Cavernosal pressure in response to cavernous nerve stimulation was decreased 4 weeks after propranolol treatment （P〈0.01, compared to the hypertensive control group）. IGFBP-3 mRNA and protein expression was increased in the propranolol treatment group compared to the hypertensive control group （P〈O.01）, whereas IGF-1 expression was decreased in the propranolol treatment group compared to the hypertensive control group （P〈0.01）. In addition, cavernous cGMP concentration was decreased in the prepranolol treatment group compared to the hypertensive control group （P〈0.01）. Taken together, these results suggest that the upregulation of IGFBP-3 may play a role in the development of ED in hypertensive rats.

关键词： erectile dysfunction insulin-like growth factor-binding protein-3 propranolol two-kidney one-clip hypertension

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Experimental investigation of hollow-core photonic crystal fibers with five photonic band-gaps

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Optoelectronics Letters 2008年第4期4卷 253-256页

作者： YUAN Jin-hui HOU Lan-tian WEI Dong-bin wang hai-yun zhou Gui-yao Institute of Infrared Optical Fibers and Sensors College of Information Science and Engineering Yanshan UniversityQinhuangdao 066004 China

The hollow-core photonic crystal fibers （HC-PCFs） with integrity structure have been fabricated with an improved twice stack-and-draw technique. The transmission spectrum shows that five photonic band-gaps within 45... 详细信息

关键词：中空光子晶体光纤光子带隙实验研究光学元件

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中国冶金分析的现状与发展(英文)

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冶金分析 2007年第1期27卷 1-6页

作者：王海舟钢铁研究总院北京100081

中国钢铁工业取得了飞速的发展。与钢铁工业的发展相对应,中国的分析测试技术特别是钢铁分析测试技术也取得长足的进步。中国的分析测试机构大体可分为承担研究任务的分析测试机构和质量监督检验机构两大类。中国金属学会是冶金领域的... 详细信息

中国钢铁工业取得了飞速的发展。与钢铁工业的发展相对应,中国的分析测试技术特别是钢铁分析测试技术也取得长足的进步。中国的分析测试机构大体可分为承担研究任务的分析测试机构和质量监督检验机构两大类。中国金属学会是冶金领域的学术团体,分析测试分会是其分支机构。中国金属学会每两年(偶数年)召开一次分析测试年会,2008年10月将在北京召开第14届年会。《冶金分析》是由中国金属学会分析测试分会主办的刊物。可循环钢铁流程分析技术及新一代钢铁材料表征技术是今后中国冶金分析测试的主要研究方向。中国实验室在进行样品分析测定时,所采用具有效力的方法基本为两个体系,即中国国家标准推荐方法体系(GB)以及国家分析测试体系(NAS)。中国有证参考物质(CRM)生产单位研制的CRM一般选择国家计量系统(GBW)、国家标准系统(GSB)或行业(如冶金认证YSB)进行认证,近年来开始根据ILAC导则13由中国合格评定国家认可委员会(CNAS)对CRM生产者进行认可。在中国,向社会提供公证数据的实验室一般都同时通过实验室认可(CNAS )和计量认证(CMA)双重认可,以保证其出具数据的法律效力,同时又为各国互认。CNAS金属专业能力验证工作组负责金属专业能力验证项目的规划协调。中实国金实验室能力验证中心是能力验证技术的研究与项目组织独立机构。

关键词：中国金属学会学术会议有证参考物质推荐方法能力验证

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金属中氢的分析技术进展

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冶金分析 2007年第3期27卷 37-44页

作者：王蓬王海舟钢铁研究总院北京100081 钢铁研究总院

介绍了金属中氢的存在状态及其对材料的影响。总结了近年来金属中氢的检测方法及目前实验室常用的测氢设备以及分析方法。除常规取样、实验室检测方法外,由于工艺的要求,在线检测手段发展越来越快。钢液、铝液中氢的在线测量技术越来越... 详细信息

介绍了金属中氢的存在状态及其对材料的影响。总结了近年来金属中氢的检测方法及目前实验室常用的测氢设备以及分析方法。除常规取样、实验室检测方法外,由于工艺的要求,在线检测手段发展越来越快。钢液、铝液中氢的在线测量技术越来越多地应用到实际生产中,并已经研制出可在线同时检测钢液中氧、氮、氢3种气体元素的检测设备。熔敷金属中氢的检测已经逐渐由热导法替代了传统的水银法和甘油法。

关键词：氢溶解度熔融热抽取扩散金属进展

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Structural Variation of the Superintegron in the Toxigenic Vibrio cholerae O1 El Tor

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Biomedical and Environmental Sciences 2011年第6期24卷 579-592页

作者： GAO Yan PANG Bo wang hai Yin zhou hai Jian CUI Zhi Gang KAN Biao State Key Laboratory for Infectious Disease Prevention and Control National Institute for Communicable DiseaseControl and Prevention Chinese Center for Disease Control and Prevention Beijing 102206 China

Objective To understand the genetic structures and variations of the superintegron （Sl） in Vibrio cholerae isolated in the seventh cholera pandemic. Methods Polymerase chain reaction scanning and fragment sequencing were used. Sixty toxigenic V. cholerae O1 El Tor strains isolated between 1961 and 2008 were analyzed. Results Some variations were found, including insertions, replacements, and deletions. Most of the deletions were probably the result of recombination between V. cholerae repeat sequences. The majority of the variations clustered together. The Sis of the strains isolated in the 1960s and 1970s showed more diversity, whereas SI cassette variations in strains isolated in the 1990s and after were lower, with -24 kb signature sequence deletion. This indicates the predominant Sl in the host during the epidemic in the 1990s and after. The insertion cassettes suggested the mobilization from the Sls of other V. cholerae serogroups and Vibrio mimicus. Conclusion The study revealed that structural variations of Sis were obvious in the strains isolated in epidemics in different decades, whereas the divergence was based on syntenic structure of Sis in these El Tot strains. Also, the continuing cassette flows in the Sis of the host strains during the seventh cholera pandemics were displayed.

关键词： Superintegron Cassette Vibrio cholerae

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A NEW SYNTHESIS OF dl- AND (R) -MUSCONE FROM CYCLODODECANONE

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Chinese Chemical Letters 1992年第4期3卷 235-236页

作者： Da Sheng wang Chang hai zhou Dao Quan wang~* Department of Applied Chemistry Beijing Agricultural University, Beijing 100094

dl-And (R)-muscone were synthesized from the readily available cyclododecanone by a free radical ring expansion in overall yields of 51% and 32% respectively.

关键词： A NEW SYNTHESIS OF dl AND MUSCONE FROM CYCLODODECANONE

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一次展示中国冶金分析研究成果的国际学术会议——中国金属学会代表团参加CETAS2006国际钢铁与金属工业分析化学进展学术会议取得圆满成功

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冶金分析 2006年第3期26卷 87-89页

作者：沈学静王海舟钢铁研究总院北京100081 钢铁研究总院

介绍了中国代表团成功参加CETAS2006国际钢铁与金属工业分析化学进展学术会议的情况。中国冶金分析领域的研究成果得到了与会国外专家的普遍关注和浓厚兴趣。同时,通过交流建立了CETAS和中国金属学会分析测试分会间沟通的桥梁。

关键词：钢铁工业分析工作研究和应用欧州委员会钢铁与金属工业分析化学

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激光诱导击穿光谱对焊缝熔合区的元素成分分布分析

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光谱学与光谱分析 2014年第4期34卷 1089-1094页

作者：杨春张勇贾云海王海舟钢铁研究总院北京100081 清华大学材料学院北京100084

激光诱导击穿光谱(LIBS)是近十几年来快速发展的一种新的表面分析工具,由于具有分析速度快、灵敏度高等优点,故在材料科学领域引起广泛的关注。文中采用LIBS、扫描电子显微镜/能谱仪(SEM/EDS)和电子探针显微分析(EPMA)三种分析方法,对... 详细信息

激光诱导击穿光谱(LIBS)是近十几年来快速发展的一种新的表面分析工具,由于具有分析速度快、灵敏度高等优点,故在材料科学领域引起广泛的关注。文中采用LIBS、扫描电子显微镜/能谱仪(SEM/EDS)和电子探针显微分析(EPMA)三种分析方法,对两类不同焊缝的熔合线区域进行线扫描分析,研究了Ni,Mn,C,Si等元素在熔合线区域含量的变化情况。结果表明,对于含量较高且焊缝和母材成分差别较大的Ni和Mn元素,三种方法获得了一致的分析结果,两试样焊缝内的Ni和Mn含量均高于母材,在熔合线区域明显体现出浓度梯度分布。三种方法根据Ni和Mn的浓度分布测得的熔合线区宽度值比较接近。对于含量较低且焊缝和母材成分差别较小的C和Si元素,采用SEM/EDS和EPMA时,焊缝与母材之间的成分差异没有分析出来;而采用LIBS时,两区域的成分差异则可以清晰的展现出来,在熔合区域能够清楚观察到浓度梯度分布曲线。LIBS的分析灵敏度明显高于SEM/EDS和EPMA,在分析低含量元素时更具优势。

关键词：激光诱导击穿光谱元素成分分布焊缝熔合区

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