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Assessing the kinetic model of hydro-distillation and chemical composition ofAquilaria malaccensis leaves essential oil

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Chinese Journal of Chemical engineering 2017年第2期25卷 216-222页

作者： Mahtab Samadi Zurina Zainal Abidin Robiah Yunus Dayang Radiah Awang Biak Hiroyuki Yoshida eng hai lok Department of Chemical and Environmental engineering Faculty of EngineeringUniversity Putra MalaysiaserdangSelangorDaml Ehsan 43400Malaysia Aerospace Manufacturing Research Centre(AMRC) Level 7Tower BlockFaculty of EngineeringUniversity Putra Malaysia43400 5erdang SelangorMalaysia Forest Research Institute Malaysia 52109 Kepong5elangorDarul EhsanMalaysia

This study aimed to model the kinetic of hydro-distillation of Aquilaria malaccensis leaves oil in order to understand and optimize the extraction process. In addition, this study, for the first time, aimed to identify the chemical compositions of the A. rnalaccensis leave-oil. By assessing both first-order kinetic model and the model of simultaneous washing and diffusion, the result indicated that the model of simultaneous washing and diffusion better describes the hydro-distillation mechanism of the essential oil from A. rnalaccensis leaves. The optimum time, solid to liquid ratio, and the heating power for extracting the highest amount of essential oil were found to be around 3 h, 1：10 （g. ml-1）, and 300 W respectively. Yellow essential oil with a strong smell and a yield of 0.05 v/w was extracted by hydro-distillation Clevenger apparatus. Chemical compounds of the essential oil were analyzed using gas chromatography-mass spectroscopy （GC/MS）, which resulted in identification of 42 compounds that constitute 93% of essential oil. Among the identified components, Pentadecanal （32.082%）, 9-Octadecenal, （Z）（15.894%）, and Tetradecanal （6.927%） were the major compounds. Considering the fact that all the identified major components possess pesticidal properties, A. malaccensis leaves can be regarded as a promising natural source for producing pesticides.

关键词： Aquilaria malaccensisEssential oilHydro-distillationOptimizationKinetic modeling

Electromagnetic wave propagation of wireless capsule endoscopy in human body

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Journal of Central South University 2013年第10期20卷 2650-2656页

作者： LIM eng-Gee 王炤陈瑾慧 TILLO Tammam MAN Ka-lok Department of Electronic and Electrical engineering Xi’an Jiaotong-Liverpool University

Wireless capsule endoscopy(WCE) is a promising technique which has overcome some limitations of traditional diagnosing tools, such as the comfortlessness of the cables and the inability of examining small intestine section. However, this technique is still far from mature and asks for the feasible improvements. For example, the relatively low transmission data rate and the absence of the real-time localization information of the capsule are all important issues. The studies of them rely on the understanding of the electromagnetic wave propagation in human body. Investigation of performance of WCE communication system was carried out by studying electromagnetic(EM) wave propagation of the wireless capsule endoscopy transmission channel. Starting with a pair of antennas working in a human body mimic environment, the signal transmissions and attenuations were examined. The relationship between the signal attenuation and the capsule(transmitter) position, and direction was also evaluated. These results provide important information for real-time localization of the capsule. Moreover, the pair of antennas and the human body were treated as a transmission channel, on which the binary amplitude shift keying(BASK) modulation scheme was used. The relationship between the modulation scheme, data rate and bit error rate was also determined in the case of BASK. With the obtained studies, it make possible to provide valuable information for further studies on the selection of the modulation scheme and the real-time localization of the capsules.

关键词： wireless capsule electromagnetic wave propagation transmission channel

The Role of engineer-in-Chief and the Introduction of Foreign Hydraulic Dredging Technology and River Conservancy into China,1890s-1930s

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Frontiers of History in China 2020年第2期15卷 234-267页

作者： Yi Wei Long Denggao Pierre van der eng Center for Chinese Entrepreneur Studies School of Social SciencesTsinghua UniversityBeijing 100084China Research School of Management College of Business and EconomicsThe Australian National UniversityCanberra ACT 0200Australia

This paper discusses studies of the development of river conservancy in modern China,and the role of engineers-in-chief in river improvement planning on rivers such as the hai-ho(haihe)and the Whangpoo(Huangpu).It discusses the introduction of foreign hydraulic dredging technology and management into two major Chinese *** then analyses the process by which two agencies of the Chinese government absorbed and adjusted this technology to suit local circumstances in the treaty ports of Tianjin and Shanghai beginning in the *** prior experience in river conservancy,the conservancy boards adopted a range of foreign *** allowed them to develop into major institutions that facilitated increasing trade flows between China and the rest of the *** particular significance in this process of technological change was the role of the expatriate engineers-in-chief who were employed as chief executive officers of both *** were responsible for establishing the operations of the agencies,accommodating an increasing range of responsibilities such as financial and human resource management,and training Chinese engineers and managers for senior positions until they were ready to replace the expatriate engineers-in-chief after the 1930s.

关键词： technological change hydraulic engineering river conservancy engineer-in-chief

A Stream Control Transmission Protocol Based OAM System of 3G Cellular Network

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Journal of Shanghai Jiaotong university(Science) 2005年第3期10卷 245-249页

作者：郭强朱杰张海滨 Dept. of Electronic eng. Shanghai Jiaotong Univ. Shanghai 200030 China

OAM (Operations, Administration and Maintenance) system is a very impo rtant component of 3G cellular network. In order to acquire overall managemen t, fast response and steady operation, an SCTP (Stream Control Transmission Prot ocol) based OAM, i.e., SOAM system was proposed. SOAM implements new characters of SCTP such as multi-stream, enforced SACK and heartbeat mechanism on its tran sport layer. These characters help SOAM decrease the message transmission delay and accelerate the link failure detection. Besides, a new component named SOAM agent was introduced to improve the operation efficiency of SOAM. The experim ental results prove the proposed SOAM system achieves better performance on sign aling transmission compared with conventional TCP based OAM system.

关键词： stream control transmission protocol (SCTP) operations, administration and maintenance (OAM) signaling transmission 3G cellular network

Insight from Japan’s Hydrogen Strategy and Activities

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engineering 2021年第6期7卷 722-725页

作者： hai-Wen Li Nobuyuki Nishimiya Hefei General Machinery Research Institute Hefei 230031China Nihon University Tokyo 101-8308Japan

Hydrogen is globally expected to play a key role in the sustainable development of humanity,as it can be produced from renewable energy,which is more evenly distributed than fossil fuels,and can be converted into electricity and heat without the emission of greenhouse *** importance of hydrogen energy has become increasingly obvious,especially in the context of large-scale energy storage and transport for the widespread use of renewable *** is a world leader in advanced hydrogen energy technologies,based upon its continuous engagement in the development of hydrogen-related materials.

关键词： materials. energy. Japan

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全球化视阈下民族认同与中华文化创新

大连理工大学学报（社会科学版） 2014年第3期35卷 17-22页

作者：曹海峰暨南大学人文学院广东珠海519072

民族认同作为经历了历史积淀而植根于深层意识中的心理建构,会在历史进程中或者被强化或者被削弱。全球化语境中的民族认同不仅涉及成员对民族历史与文化的追溯、挖掘与重构,而且也关涉各"民族—国家"之间的政治及文化博弈,自我与他者... 详细信息

民族认同作为经历了历史积淀而植根于深层意识中的心理建构,会在历史进程中或者被强化或者被削弱。全球化语境中的民族认同不仅涉及成员对民族历史与文化的追溯、挖掘与重构,而且也关涉各"民族—国家"之间的政治及文化博弈,自我与他者的冲突与博弈。应对文化霸权以其发达强势的文化渗透所造成对民族传统文化的冲击与断裂,不是简单的"回顾"与"模仿"而是"创新"与"重构",必须要认真反思"认同危机"与"文化空场"问题,从战略高度上采取种种措施建构中华民族共同体意识,积极"创新"中华民族特色文化与"建构"民族文化身份。

关键词：全球化民族认同文化身份文化创新

Crystal Structure of {(PPh_3)_2RuB_(10)H_8[(CH_3)_2CHO]_2}

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Chinese Journal of Structural Chemistry 1997年第4期16卷 258-262页

作者： HU Chun-Hua YAO hai-Jun JIN Ruo-Shui eng Pei-Ju(Research Center of Analysis and Measurement, Fudan University, Shanghai 200433)(Department of Chemistry, Fudan University, Shanghaui 200433) 复旦大学分析测试中心上海复旦大学化学系上海

The title compound (Ⅰ) has been synthesized by the reaction of [RuCl2(PPh3)3], closo-[B10H10]2- and PhCH(OH)COOH in (CH3)2CHOH solution. The re-action gave two main products Ⅰ and Ⅱ. Crystals of the title compound (Ⅰ) suitable fora single crystal X-ray diffraction analysis were recrystailized from n-pentane/CH2Cl2 so-lution. Its structure was determined by X-ray crystallography analysis. The crystal of{(PPh3)2RuB10 H8 [(CH3)2CHO]2} (Ⅰ) is monoclinic, space group P21/n, Mr =860. 01, with a= 12. 927(2), b= 23. 672(6), c= 14. 090(4) A, β=93. 22(2)°, V=4305 A3, Dc= 1. 327 g/cm3, Z= 4, λ(MoKα) =0. 71073A, μ=4. 6 cm-1, F(000) =1776, R = 0. 059, Rw = 0. 075, S = 2. 62. The cluster structure is based on a closoeleven-vertex {RuB10 } polyhedron skeleton with two replacing isopropoxy and twoPPh3 groups.

关键词： crystal structure metallaborane ruthenaborane

基于LS-DYNA的不锈钢车顶弯梁拉弯仿真

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塑性工程学报 2015年第2期22卷 24-29,83页

作者：滕克磊金朝海南车青岛四方机车车辆股份有限公司青岛266111 北京航空航天大学机械工程及自动化学院北京100191

采用LS-DYNA软件对某帽型不锈钢车顶弯梁零件位移控制模式下的拉弯成形进行模拟分析,有效预测了拉弯过程中可能存在的成形缺陷,如截面畸变、中间段弓起、回弹,并提出了相应的解决方案,为该车顶弯梁的精确拉弯成形提供指导。

关键词：拉弯成形不锈钢车顶弯梁数值模拟

DSC Analysis of LT-3 Aluminum Alloy Vacuum Brazing

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Journal of Shanghai Jiaotong university(Science) 2005年第2期10卷 182-185,189页

作者：冯涛吴鲁海楼松年李亚江 School of Materials Science and eng. Shanghai Jiaotong Univ. Shanghai 200030 China School of Materials Science and eng. Shandong Univ. Ji'nan 250061

LT-3 aluminum alloy is a kind of two-side cladding aluminum special used in vacuum brazing. Differential Scanning Calorimeter （DSC） was used to measure the exothermic and endothermic reaction during the brazing process that the cortex metal and the base metal are melted and re-crystal. The analysis results inidicate that eutectic reaction is the main reaction in the melted cortex metal crystallization process. But the main reaction in the melted base metal crystallization process is the reaction that α-A1 segregated out. According to the experimental details, the critical work of nucleation is 3.82×10-17J, the critical radius of nucleation is 8.69×10-10 m, the volume of critical crystal nucleus is 2.75×10-27 m3 and the per unit cell in critical crystal nucleus is 43.

关键词： aluminum alloy differential scanning calorimeter(DSC) analysis critical nucleation