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Unprecedented Double C-C Bond Cleavage of a Cyclopentadienyl Ligand in Titanacyclopentadiene

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Unprecedented Double C-C Bond Cleavage of a Cyclopentadienyl...

中国化学会第十三届金属有机化学学术讨论会

作者： tamotsu takahashi Catalysis Research Center Hokkaido UniversitySapporo 060-0811Japan

＜正＞ For more man 50 years, the cyclopentadienyl （Cp） ligand has been extensively utilized as a famous stable ligand in organometallic chemistry. It is the η5-Cp binding mode that makes the Cp ligand act as "spectator", staying unchangeable throughout the course of the reaction. In this contribution, we wish to report an unprecedented double C-C bond cleavage reaction of a cyclopentadienyl ligand.

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Formation for Vinyl Allenes from 1-Lithio-1,3-Butadienyl Phosphine Oxides and Aldehydes

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Formation for Vinyl Allenes from 1-Lithio-1,3-Butadienyl Pho...

中国化学会第十三届金属有机化学学术讨论会

作者： tamotsu takahashi Catalysis Research Center Hokkaido UniversitySapporo 060-0811Japan

＜正＞ Vinyl allenes bearing a cumulenic and conjugated vinyl functionality have become versatile precursors or intermediates in organic synthesis. Therefore, development ofsynthetically useful methods for the formation of vinyl allenes continues to be a very attractive area. We have recently investigated these reactions of 1-lithio-1,3-dienes and unsaturated substrates. Treatment of l-lithio-l,3-dienes with aldehydes or ketones can afford stereodefined

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β-Hydride Abstraction from α-Positioned Methyl Group of Bicycliczirconacyclopentanes Assisted by Coordination of Aldehyde

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β-Hydride Abstraction from α-Positioned Methyl Group of Bi...

中国化学会第十三届金属有机化学学术讨论会

作者： tamotsu takahashi Catalysis Research Center Hokkaido UniversitySapporo 060-0811Japan

＜正＞ β-Hydride abstraction is one of the fundamental reactions of organometallic compounds and has been accepted as one of the most attractive approaches in synthetic chemistry. The β-hydrogen of linear alkyl groups in organometallic compounds as 1 easily undergo β-hydride abstraction （eq 1）. The type of β-hydrogen in bicyclicorganometallic compounds 2 is also known to undergo abstraction reactions （eq 2）. However, although the type of bicyclicorganometallic compounds 3 can be readily prepared and have been used in organic synthesis. P-hydride abstraction from the α-positioned alkyl groups has not been reported.

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An Efficient Method for Preparation of Thiophenes by the Direct Reaction of Zirconacyclopentadienes and Sublimed Sulfur

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An Efficient Method for Preparation of Thiophenes by the Dir...

中国化学会第十三届金属有机化学学术讨论会

作者： tamotsu takahashi Catalysis Research Center Hokkaido UniversitySapporo 060-0811Japan

＜正＞ Thiophenes have long played an important role in pharmaceutical chemistry and material science. Therefore, new methods of higher efficiency and greater generality are in great demand, although many means for the preparation of thiophenes have appeared. Metallacycle transfer from zirconacyclopentadienes to main group elements is an alternative method to synthesize heterocyclic compounds （eq 1）. Generally, the heteroatom compound must bear

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A NEW HIGH ORDER SCHEME FOR CONVECTION EQUATION AND ITS APPLICATION

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Journal of Hydrodynamics 2002年第1期14卷 81-86页

作者： Zhang Xiao-feng (Department of River Engineering, Wuhan University, Wuhan 430072, China) Zhang Hong-wu (Department of Hydraulic Engineering, Tsinghua University, Beijing 100084, China) tamotsu takahashi, Hajime Nakagawa (Disaster Prevention Research Dept. of River Eng. Wuhan Univ. Wuhan 430072 China

With the undetermined coefficient method, a new high order scheme for convection equation named as HAUC was worke d out. The accuracy of the new scheme was analyzed by comparing the computed res ults with the exact solutions of 1-D pure convection equation and nonlinear con vection equation. The effectiveness of the HAUC was also examined by comparing w ith the results obtained by other schemes. Finally, it was applied to simulate 1 -D dam break flow with differenct ratios of initial upstream water depth to do wnstream one. The results show that the scheme has the ability to simulate both undular bores and moving hydraulic jumps.

关键词： higher order scheme undetermined co efficient method dam break flow undular bore moving hydraulic jump

过渡金属促进的从三种不同的炔烃高效合成苯衍生物的策略

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化学学报 2000年第10期58卷 1177-1185页

作者：席振峰高桥保北京大学化学学院北京100871 日本北海道大学触媒化学研究中心

报道利用过渡金属有机化合物(二茂锆和有机铜化合物),从三种不同的炔烃,如何实现了高选择性高产率并且一锅煮地合成苯衍生物.

关键词：二茂锆有机铜炔烃苯衍生物合成一锅法

五四新文化运动时期中国的婚姻制度与女性的地位

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中文论坛 2018年第2期 240-254页

作者： [日]高桥保() 黄凤琴(译) 梁艳萍(校) 日本城西国际大学湖北大学外国语学院湖北大学文学院

本文以五四新文化运动为历史背景,探讨这一时期的妇女在婚姻制度中的地位与妇女解放进程。本文主要分为四个部分:第一部分分析清朝末期(1911)基于中国传统的儒教伦理的婚姻制度以及女性的从属地位,认为在鸦片战争后中国开始进入现代进... 详细信息

本文以五四新文化运动为历史背景,探讨这一时期的妇女在婚姻制度中的地位与妇女解放进程。本文主要分为四个部分:第一部分分析清朝末期(1911)基于中国传统的儒教伦理的婚姻制度以及女性的从属地位,认为在鸦片战争后中国开始进入现代进程之后,已经出现了对于儒教思想的批评以及反对性别歧视的活动;第二部分考察辛亥革命后军人政权下的婚姻制度依然是维持妇女低下地位的保守性制度;第三部分审视在新文化运动的发生与《新青年》杂志出版的时间阶段,对于儒教的批判与女性解放的历史实存;第四部分重点考察了五四新文化运动时期妇女在婚姻制度中的地位,发现大城市的青年知识分子在运动的影响下开始选择爱情婚姻,而在农村偏远地区,传统的婚姻制度仍然继续维持,基于儒家伦理的妇女地位依然非常低下。

关键词：五四新文化运动婚姻制度女性地位

Simulation and Calibration of Hydro-Debris 2D Model （HD2DM） to Predict the Particle Segregation Processes in Debris Flow

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Journal of Civil Engineering and Architecture 2012年第6期6卷 690-698页

作者： Yosuke Yamashiki Mohd Remy Rozainy M. A. Z.: Taku Matsumoto tamotsu takahashi Kaoru Takara Department of Urban and Environmental Engineering Kyoto University Kyoto 615-8530 Japan Science and Technology Research Partnership for Sustainable Development Tokyo 102-0076 Japan School of Civil Engineering Universiti Sains Malaysia Penang 14300 Malaysia Sumitomo Corporation Tokyo 104-8610 Japan Association for Disaster Prevention Research Kyoto 606-8226 Japan

The principal aim of a vertical two-dimensional numerical model development is for estimating the particle tracing and mechanism of 10 mm and 2.5 mm debris. The particle tracing movement can be visually analyzed by using a high speed video camera (HSVC). A numerical model was developed using the Marker and Cell Method, which involves a Subgrid-Scale (SGS) model and the Particle Source in Cell (PSI-Cell) Method. The transportation processes of debris and air bubble were simulated in lagrangian form by introducing air bubbles and debris markers. Air bubble movement characteristics were simulated by this numerical model. Bigger particles flow at the upper part, while smaller particles attach near to the bottom. This phenomenon is similar to what we observed in the experimental studies. As a conclusion, the calibration processes for velocity was successful. The value of virtual mass (CM) was found to be one of the most important criteria that should be considered in the calibration process, as this parameter dominates fundamental characteristics of sediment particle movement in the lagrangian numerical scheme. The best fitted CM in this study was 0.35. The mean average velocity value ranging from 1.2% to 22.61% is obtained from the velocity results of numerical studies compared to the experimental studies.

关键词：过程模拟模型开发校准颗粒分离泥石流 2D 水电预测