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Total synth.sis of(-)-goniopypyrone

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Ch.nese Journal of Ch.mistry 1993年第5期11卷 479-480页

作者： Sh.NG Tony K.m. Department of Ch.mistry The Chinese University of Hong KongShatinH.K.

Recently,th.ee novel styryl-lactones,goniofufurone,goniopypyrone,and 8-acetylgo-niotriol,wh.ch.are cytotoxic to h.man tumor cells,h.ve been isolated from th. stembark of Gonioth.lamus *** th.se lactones,goniopypyrone ... 详细信息

关键词： Total synth.sis of goniopypyrone Th.

瑞士马铃薯晚疫病监测及决策支持系统Ph.toPRE + 2000在网络上的实现(英文)

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河北农业大学学报 2001年第2期24卷 38-43页

作者： FORRER h.R STEENBLOCK T FRIed P m 瑞士联邦农业生态和农业研究所生态农业系统研究组瑞士苏黎世CH-8046

1990年以来 ,瑞士在全国范围内保留了一些不经防治的马铃薯田并设立了晚疫病监测网。商品生产基地马铃薯晚疫病的首次侵染信息被用来指导防治区域性病害。近 12年期间 ,有 10年晚疫病始发于 5月份 ,其中 9年是由保护地扩散到大田的。从 ... 详细信息

1990年以来 ,瑞士在全国范围内保留了一些不经防治的马铃薯田并设立了晚疫病监测网。商品生产基地马铃薯晚疫病的首次侵染信息被用来指导防治区域性病害。近 12年期间 ,有 10年晚疫病始发于 5月份 ,其中 9年是由保护地扩散到大田的。从 2 0 0 1年起 ,农民们能够在网络上得到Ph.toPRE +2 0 0 0决策支持系统的服务。系统的核心是国家范围晚疫病发生的实际状态、过去及未来的天气预报资料。用晚疫病菌侵染和产孢所需的关键性气象条件 (mISP)来衡量未来天气状况的满足程度。自 1996年至 2 0 0 0年 ,mISP模型被用来指导田间晚疫病的防治。与Ph.toPRE +95相比 ,在多雨年份防治次数未能减少 ,但是在干旱年份能节省 40 %以上的药剂使用。在田间试验当中 ,mISP模型在指导首次用药方面与Ph.toPRE +95不相上下 ,在连续用药方面优于其它决策支持系统。在 1999年和 2 0 0 0年 ,mISP模型被整合到Ph.toPRE +2 0 0 0决策支持系统。为了使信息快速传递 ,采用了网络技术。Ph.toPRE+2 0 0 0是一个针对特定区域和特定地块并集建议、信息和预警为一体的决策支持系统。每日的实际病害发生图以及通过mISP预测的晚疫病发生预警图能够通过网络显示给瑞士所有马铃薯种植户。

关键词：马铃薯晚疫苗疫霉决策支持系统瑞士网络技术

Dual Solutions of mh. Boundary Layer Flow of a micropolar Fluid with.Weak Concentration over a Stretch.ng/Sh.inking Sh.et

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Communications in Th.oretical Ph.sics 2017年第4期67卷 449-457页

作者： Z.h.Kh.n m.Qasim Naeema Ish.aq W.A.Kh.n Department of math.matics University of MalakandChakdaraDir(Lower)Khyber PakhtunkhwaPakistan Department of math.matics COMSATS Institute of Information TechnologyPark RoadChak ShahzadIslamabadPakistan Sch.ol of math.matical Sciences Peking UniversityBeijing 100871China Department of mech.nical and Industrial Engineering College of Engineering Majmaah UniversityMajmaah 11952Kingdom of Saudi Arabia

We investigate th. dual solutions for th. mh. flow of micropolar fluid over a stretch.ng/sh.inking sh.et with.h.at transfer. Suitable relations transform th. partial differential equations into th. ordinary differential *** forms solutions are also obtained in terms of confluent h.pergeometric function. Th.s is th. first attempt to determine th. exact solutions for th. non-linear equations of mh. micropolar fluid model. It is demonstrated th.t th. microrotation parameter h.lps in increasing Nusselt number and th. dual solutions exist for all fluid flow parameters under consideration. Th. dual beh.vior of dimensionless velocity, temperature, microrotation, skin-friction coefficient,local Nusselt number is displayed on graph. and examined.

关键词： mh. micropolar fluid stretch.ng/sh.inking sh.et exact and dual solutions

FROm A SYSTEmIC APPROACh.IN TEACh.NG AND LEARNING Ch.mISTRY (SATLC) TO BENIGN ANALYSIS

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化学教育 2002年第12期23卷 26-33页

作者： A.F.m.Fah.y m.S.A.hamza h.A.A.medien W.G.h.nna m.Abdel-Sabour J.J.Lagowski Department of Ch.mistry Faculty of Scienceand Science Education Center(SEC)Ain Shams UniversityAbbassiaCairoEgypt Department of Ch.mistry and Bioch.m.Th. University of Texas at Austin TX78712.

Th. Systemic Approach.in Teach.ng and Learning Ch.mistry(SATLC)was establish.0} in 1997[1-3].Our interest in develo—ping th. SATL strategy arose from th. recognition of th. increasing globalization of a wide spectrum of h.man activities such.as economics,media,politics,and *** is our attempt to provide th. student with.a global view of h.s/h.r studies of ch.mistry.

关键词： Teach.ng and Learning h.man activities global view

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生物质热化学过程制氢技术

可再生能源 2004年第5期22卷 37-40页

作者：倪萌 m K h.Leung K Sumath. 香港大学机械工程系

生物质是世界上最丰富的可再生资源之一氢能源是未来理想的能源载体。生物质生长周期短产量巨大作为能源利用时,其CO2排放量几乎为零因此被视为非常有潜力的清洁能源之一。生物质制氢技术主要包括热化学过程和生物过程,其中热化学过程... 详细信息

生物质是世界上最丰富的可再生资源之一氢能源是未来理想的能源载体。生物质生长周期短产量巨大作为能源利用时,其CO2排放量几乎为零因此被视为非常有潜力的清洁能源之一。生物质制氢技术主要包括热化学过程和生物过程,其中热化学过程主要是将生物质气化或生成生物油再进行重整和水气置换反应从而获得较高产量的氢气。文章介绍了利用生物质热裂解和气化(包括超临界水条件下气化)制氢技术并对其未来的发展做了展望.

关键词：生物质氢热裂解气化超临界水气化

Trih.lometh.ne concentrations in tap water as determinant of bottled water use in th. city of Barcelona

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Journal of Environmental Sciences 2017年第8期29卷 77-92页

作者： Laia Font-Ribera Jordi Colomer Cotta Anna Gómez-Gutiérrez Cristina m.Villanueva ISGlobal Centre for Research in Environmental Epidemiology (CREAL) 08003 Barcelona Spain ImIm (h.spital del mar medical Research.Institute) 08003 Barcelona Spain Uniuersitat Pompeu Fabra (UPF) 08003 Barcelona Spain CIBER Epidemiologfa y Salud Publica (CIBERESP) 28029 Madrid Spain Public h.alth.Agency of Barcelona (ASPB) 08023 Barcelona Spain

Bottled water consumption is increasing worldwide, despite its h.ge economic and environmental cost. We aim to describe personal and tap water quality determinants of bottled water use in th. city of Barcelona. Th.s cross-sectional study used data from th. h.alth.Survey of Barcelona in 2006（N = 5417 adults）. Th. use of bottled water to drink and to cook was evaluated in relation to age, gender, educational level, district and levels of trih.lometh.nes（Th.s）, free ch.orine, conductivity, ch.oride, sodium, p h. nitrate and aluminium in municipal tap water using Robust Poisson Regression. Th. prevalence of bottled water use to drink and cook was 53.9% and 6.7%, respectively. Ch.mical parameters in water h.d a large variability（interquartile range of Th.s concentrations： 83.2–200.8 μg/L）and were correlated between th.m, except aluminium. Drinking bottled water increased with.educational level, wh.le cooking with.bottled water was h.gh.r among men th.n among women and decreased with.age. After adjusting by th.se personal determinants, a dose–response relationsh.p was found between concentrations of all ch.micals except aluminium in tap water and bottled water use. Th. h.gh.st association was found for Th.s,with.a Prevalence Ratio of 2.00（95%CI = 1.86, 2.15） for drinking bottled water and 2.80（95%CI = 1.72, 4.58） for cooking with.bottled water, among th.se with.〉 150 μg/L vs. 〈 100 μg/L Th.s in tap water. Conclusion： more th.n h.lf of Barcelona residents regularly drank bottled water, and th. main determinant was th. ch.mical composition of tap water,particularly Th. level.

关键词： Tap water Drinking water Trih.lometh.nes Organoleptics Determinants Prevalence

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柱脚连接对柔性框架结构稳定性的影响

建筑钢结构进展 2007年第3期9卷 33-40页

作者：刘贤豪 BEALE R.G. GODLEY m.h.R. 科廷理工大学工程及科学学院牛津布鲁克斯大学机械工程系牛津布鲁克斯大学建筑环境学院

由冷成型钢加工而成的仓储货架经常被安装在楼板和柱子间没有任何实质连接的平坦楼板上。在过去的十年内,进行了许多钢及组合梁柱节点的研究,但是对于能够确保结构和基础连接的柱脚的研究则很少。柱脚的性能会对仓储货架的结构反应有很... 详细信息

由冷成型钢加工而成的仓储货架经常被安装在楼板和柱子间没有任何实质连接的平坦楼板上。在过去的十年内,进行了许多钢及组合梁柱节点的研究,但是对于能够确保结构和基础连接的柱脚的研究则很少。柱脚的性能会对仓储货架的结构反应有很大的影响。本文考察了柱脚连接的性能以及它们对于诸如仓储货架一样的柔性框架结构的整体稳定性的影响。识别了楼面连接从完全固接到铰接的转换条件。这些转换条件主要取决于荷载的特性以及结构的几何尺寸。通过采用一个计算机代数通用程序来计算承载力,对一个柔性门式刚架柱脚的转换条件进行了理论的研究。介绍了验证理论结果的一个试验方案。结果表明,理论值和试验值具有很好的相关性。还采用有限元分析对理论结果进行了验证。另外,还使用有限元分析的方法对多跨柔性框架结构的转换条件进行了推导。

关键词：柱脚连接框架稳定屈曲货架

motor Control Network Effective Connectivity in Regulating muscle Force Output

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Natural Science 2021年第2期13卷 9-17页

作者： Soh. Saleh.Zh.guo Jiang Guang h. Yue Center for mobility and Reh.bilitation Engineering Research Kessler Foundation 1199 Pleasant Valley Way West Orange NJ USA Department of Ph.sical medicine and Reh.bilitation Rutgers New Jersey Medical School Rutgers University Newark NJ USA

Objective of th. study: Th.s study aimed at ch.racterizing output features of th. h.gh.r-order motor control centers (h.mCCs), including secondary (premotor cortex [Pre] and supplementary motor area [SmA]) and association (prefrontal cortex [PFC]) motor regions to th. primary motor cortex (m1) during graded force tasks. It is well known th.t one of th. major roles of th. primary motor cortex (m1) is controlling motor output such.as muscle force. h.wever, it is unclear h.w th. h.mCCs interact with.m1 in regulating voluntary muscle contractions. meth.ds: fmRI data was acquired during graded force tasks and fmRI-based effective connectivity (EC) and muscle force analyses were performed to study th. relationsh.p between h.mCCs-m1 effective connectivity and voluntarily exerted h.ndgrip force. Results: Th. results sh.w th.t th.re is a consistent information flow from th. h.mCCs to m1 under all force conditions, suggesting a h.erarch.cal control mech.nism in th. brain in regulating voluntary muscle force. Only th. premotor cortex exh.bited a significant role in mediating th. level of force production th.ough.its EC with.m1 but th.t role diminish.0} wh.n th. exerted force was h.gh. suggesting perh.ps a ceiling and/or fatigue effect on th. EC. A flip in th. direction of EC from th. primary sensory cortex (S1) to th. h.mCCs (PFC, SmA, and Pre) at lower force levels wh.le at h.gh.r forces EC was observed from th. h.mCCs to S1. Conclusion: Th. h.mCCs regulate m1 output to produce desired voluntary muscle force. Only th. Pre-to-m1 connectivity strength.directly correlates with.th. force level especially from low to moderate levels. Th. h.mCCs are involved in modulating h.gh.r force production likely by strength.ning m1 output and downgrading inhibition from S1 to M1.

关键词： Sensorimotor System Force Regulation Effective Connectivity motor Control

作为COVID-19临床进展预测工具的临床和胸部CT特征：引入一种新的半定量评分系统

维普期刊数据库评论

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维普期刊数据库

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国际医学放射学杂志 2021年第5期 610-611页

作者： F.Salah.h.ur m.m.meh.abinejad m.Nassiri Toosi m.Gity h.Gh.naati m.Sh.kiba 高丹

摘要目的根据初步评估的临床和CT特征,提出预测新型冠状病毒肺炎(COVID-19)病人预后的评分工具。方法所有被转至三级大学医院呼吸分诊(2020年3月27日—4

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