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Composition of Essential Oils from Litsea acutivenaHayata

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American Journal of Plant Sciences 2019年第4期10卷 615-621页

作者： Do N. Dai Nguyen t. t. Lam Nguyen A. Dung Le t. Huong Dao t. M. chau Isiaka A. Ogunwande Graduate University of Science and technology Vietnam Academy of Science and Technology Hanoi Vietnam Faculty of Agriculture Forestry and Fishery Nghean College of Economics Vinh Vietnam School of Natural Science Education Vinh University Vinh Vietnam 7 University Drive Aleku Area Osogbo Nigeria

the chemical components of the leaf oil of Litsea acutivena Hayata collected from Pù Huong Natural Reserve, Nghe An Province, Vietnam, were identified by co-chromatography with authentic samples, gas chromatography/mass spectrometry (GC/MS) and linear retention indices. the significant compounds of L. acutivena were α-phellandrene (30.4%) and α-pinene (14.2%). the constituents of essential oil of L. acutivena from Vietnam are being reported for the first time.

关键词： Litsea acutivena Essential Oil terpenes

Constituents of Some Essential Oil Bearing Plants from Vietnam

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American Journal of Plant Sciences 2014年第5期5卷 760-765页

作者： Le t. M. chau tran D. thang Le V. Diep Nguyen t. M. tu Isiaka A. Ogunwande Faculty of Chemistry Vinh University Vinh Vietnam Natural Products Research Unit Department of Chemistry Faculty of Science Lagos State University Lagos Nigeria School of Biotechnology and Food technology Hanoi University of Science and Technology Hanoi Vietnam

Essential oils obtained from hydrodistillation of three medicinal plants grown in Vietnam were analyzed by gas chromatography (GC) and gas chromatography/mass spectrometry (GC-MS). the monoterpene hydrocarbons, α-pinene (50.2%), β-pinene (23.6%) and limonene (5.3%) were the most abundant constituents of the rhizome oil of Zingiber collinsii Mood & theilade (Zingiberaceae). the main compounds of the stem oil of Croton kongensis Gagnep., (Euphorbiaceae) were benzyl benzoate (12.7%), β-selinene (9.8%), bulnesol (8.0%) and 5,6,7,8-tetrahydroquinoxaline (7.4%). the leaf oil of Goniothalamus albiflous Ban., consisted mainly of α-pinene (26.2%), caryophyllene oxide (10.6%) and 1,8-cineole (9.7%). the composition of the oils of Zingiber collinsii and Croton kongensis was being reported for the first time.

关键词： Zingiber collinsii Croton kongensis Goniothalamus albiflorus Essential Oil terpenes

Chemical Constituents of the Root Essential Oils of Zingiber rubensRoxb., and Zingiber zerumbet(L.) Smith

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American Journal of Plant Sciences 2013年第1期4卷 7-10页

作者： Do N. Dai tran D. thang Le t. M. chau Isiaka A. Ogunwande Faculty of Biology Vinh University Vinh City Vietnam Faculty of Chemistry Vinh University Vinh City Vietnam Natural Products Research Unit Department of Chemistry Faculty of Science Lagos State University Lagos Nigeria

Zingiber rubens Roxb., and Zingiber zerumbet (L.) Smith were collected respectively from Nghe An, Province and Ha tinh, Province,Vietnam. the root essential oils were obtained by water distillation and analyzed by Gas chromatography (GC) and Gas chromatography coupled with Mass spectrometry (GC-MS). the most abundant components of Z. rubens were (Z)-citral (30.1%), camphene (9.7%), β-phellandrene (7.5%) and 1,8-cineole (7.0%) and zingiberene (5.3%). the main oil constituents of Z. zerumbet were (Z)-citral (26.1%), camphene (16.3%), sabinene (14.6%), zingiberene (7.2%) and lavandulyl acetate (6.7%). this species has low zerumbone (1.2%) content.

关键词： Zingiber rubens Zingiber zerumbet Root Essential Oil (Z)-Citral Camphene Sabinene Zerumbone

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裂纹与边界交叉点的奇异性理论研究(英文)

暨南大学学报（自然科学与医学版） 2005年第1期26卷 130-133页

作者：周锦添香港理工大学土木及结构工程学系

回顾和探讨了位于三维裂纹前沿和固体自由表面交叉点附近的被称作复杂尖端奇异性的问题 .结果表明 ,自由面上的裂纹边界点并不具有传统裂纹尖端应力场r- 0 .5阶的奇异性 (其中r为从裂纹尖端量起的距离 ) ,而是应该采取rλ 阶的形式 .其... 详细信息

回顾和探讨了位于三维裂纹前沿和固体自由表面交叉点附近的被称作复杂尖端奇异性的问题 .结果表明 ,自由面上的裂纹边界点并不具有传统裂纹尖端应力场r- 0 .5阶的奇异性 (其中r为从裂纹尖端量起的距离 ) ,而是应该采取rλ 阶的形式 .其中指数λ是关于破裂模式 (即模式I、II或III) ,裂纹前沿在自由面的倾角 β ,破裂面与固体表面的夹角γ以及材料泊松比的函数 .这一问题只对极个别情况存在解析解 ,而绝大多数已知结果都是通过高精度有限元、有限差分方法和强奇异积分方程得到的 .尽管尖端奇异性问题对工程应用极其重要。

关键词：奇异性理论对极强奇异积分固体表面交叉点裂纹尖端前沿方程函数距离

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辉长岩中张开型表面裂隙破裂模式研究

岩石力学与工程学报 2007年第3期26卷 525-531页

作者：郭彦双黄凯珠朱维申周锦添李术才香港理工大学土木与结构工程系山东大学岩土与结构工程研究中心

采用含张开型表面裂隙辉长岩试样,对单轴压缩荷载作用下预制裂隙的破裂模式进行一系列试验研究。试验结果表明:预制裂隙的破裂模式是以一种新的方式——反翼裂隙(其扩展方向是与翼裂隙方向相反的)模式为主的,且新生裂隙的起裂位置并不... 详细信息

采用含张开型表面裂隙辉长岩试样,对单轴压缩荷载作用下预制裂隙的破裂模式进行一系列试验研究。试验结果表明:预制裂隙的破裂模式是以一种新的方式——反翼裂隙(其扩展方向是与翼裂隙方向相反的)模式为主的,且新生裂隙的起裂位置并不在预制裂隙的端部。翼裂隙只在试验的后期出现。预制裂隙倾角对试样的起裂应力影响较为显著,当60°≤α≤75°时,试样的起裂应力约为辉长岩抗压强度σc的75%;当30°≤α≤45°时,试样内部轴向应力值接近辉长岩抗压强度σc的90%时,预制裂隙才起裂。反翼裂隙扩展角为135°～145°,当反翼裂隙扩展长度达到预制裂隙长度的1/2时,其扩展方向基本与加载方向一致。裂隙扩展过程的声发射(AE)定位结果与试验观察结果是一致的,这表明反翼裂隙是张开型表面裂隙三维破裂模式的主要特征,反翼裂隙属于局部劈拉应力作用下的压张性裂隙(模式V),其扩展的具体理论机制目前还不清楚,值得进一步研究。此外,当预制裂隙倾角在45°附近时,试样起裂后极易发生爆裂现象,说明原生裂隙的倾角也许是影响岩爆现象的一个重要参数。

关键词：岩石力学表面裂隙翼裂隙反翼裂隙破裂模式单轴压缩

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新型外转子磁齿轮复合电机的设计与研究

中国电机工程学报 2008年第30期28卷 67-72页

作者：张东邹国棠江建中包广清蹇琳旎王建宽上海大学上海市闸北区200072 香港大学中国香港特别行政区兰州理工大学甘肃省兰州市730050

提出一种新型外转子磁齿轮复合电机,该电机将磁齿轮和无刷直流电机进行整合,电机的外转子和磁齿轮的内转子共同构成复合电机的内转子,实现了低速大转矩的直接驱动方式,同时充分利用了磁齿轮的内部空间,从而提高了整个传动系统的效率。... 详细信息

提出一种新型外转子磁齿轮复合电机,该电机将磁齿轮和无刷直流电机进行整合,电机的外转子和磁齿轮的内转子共同构成复合电机的内转子,实现了低速大转矩的直接驱动方式,同时充分利用了磁齿轮的内部空间,从而提高了整个传动系统的效率。采用时步有限元法对复合电机的磁场进行分析,充分考虑了谐波磁场的相互耦合问题,并得出复合电机的相关动态特性。这些特性揭示了复合电机非常适合与低速大转矩的直接驱动场合,但是不适合于对舒适度和位置精度要求较高的场合。制造了一台1200W原型机,并对原型机进行试验,验证了电磁理论分析结果的正确性。

关键词：磁齿轮复合电机时步有限元法无刷直流电机动态特性

traditional Chinese Medicine in Malaysia:A Brief Historical Overview of the Interactions between China and Malay Peninsula

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Chinese Medicine and Culture 2018年第2期1卷 60-63页

作者： Wen tien tan Hon Foong Wong Shih chau Ng Si Woei Goh Jun Liu Bao Ling Hoo Chyong En Chai Xun Lin Department of Golden Cabinet International Education CollegeShanghai University of Traditional Chinese MedicineShanghaiChina Department of Chinese Medicine Centre for Complementary and Alternative MedicineInternational Medical UniversityKuala LumpurMalaysia

Chinese Medicine was introduced to the Malay Peninsula during the colonial era circa 18th to 19th *** British imported Chinese immigrants mainly for tin *** early Chinese settlers had brought with them the knowledge of traditional Chinese Medicine(tCM)to *** time goes by,tCM becomes one of the popular traditional medicines that are accepted by other *** has thus contributed to the welfare of *** 2016,a traditional and Complementary Medicine(t and CM)Act was passed by the Malaysia *** is one of the t and CM practices that fall under the *** services are now offered in Malaysia’s public hospitals in addition to private *** article aims to provide a brief overview on the development of tCM in the precolonial and postindependent Malaysia.

关键词： Development history Malaysia traditional Chinese Medicine

Effects of Ving tsun sticking-hand training on upper-limb sensorimotor performance in community-dwelling middle-aged and older adults: A randomized controlled trial

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International Journal of Nursing Sciences 2020年第1期7卷 29-34页

作者： Joanne W.Y.Chung Shirley S.M.Fong Yang Gao timothy t.t.Yam Yvonne t.C.Chak Joyce C.Y.Leung thomas k.S.Wong Department of Health and Physical Education Education University of Hong KongHong KongChina School of Nursing and Healthcare Hong Kong Nang Yan College of Higher EducationHong KongChina Hong kong Martial Arts Institute Hong KongChina School of Public Health University of Hong KongHong KongChina Department of Sport and Physical Education Hong Kong Baptist UniversityHong KongChina Hong kong Christian Service Hong KongChina School of Nursing and Health Studies Open University of Hong KongHong KongChina Department of Social Work and Social Administration University of Hong KongHong KongChina

Objective:to evaluate the effects of Ving tsun(Vt)sticking-hand training on upper-limb joint position sense and muscular performance in community-dwelling middle-aged and older ***:thirty-three adults were randomly allocated to either a Vt group or a control *** Vt group received Vt sticking-hand training twice per week for 3 *** were taken before and after the intervention *** primary outcome was elbow-joint repositioning error,which was measured by an elbow-joint passive positioning and active repositioning test using a universal *** outcomes were upper-limb muscles'peak force and time taken to reach peak force as measured by a hand-held ***:No significant time,group or time-by-group interaction effects were found for elbow-joint repositioning error or upper-limb muscle peak force *** flexor time to peak force decreased by 33.8%from pre-test to post-test in the Vt group(P=0.007).Shoulder abductor,internal and external rotator,and elbow extensor times to peak force decreased by 30.0%-35.9%in the Vt%roup(Pthe control group(Pt sticking-hand training does not improve elbow-joint position sense or the maximum strength of upper-limb muscles in middle-aged and older ***,Vt can improve shoulder flexor muscles'time to reach peak force in these *** had no obvious effect on the time required to reach peak force in other shoulder muscles and elbow extensors.

关键词： Aged Exercise movement techniques Joint position sense Middle aged Muscle strength Upper extremities

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香港蒲苔群岛植物物种多样性与植被的研究

中山大学学报（自然科学版） 2005年第B6期44卷 236-241页

作者：周劲松王发国邢福武周锦超 Richard t Corlett 中国科学院华南植物园嘉道理农场暨植物园香港大学生态及分类学系

通过实地调查,对香港蒲苔群岛的植物物种多样性进行了研究。据统计蒲苔群岛共有维管束植物245种,隶属于93科203属,其中有国家及香港政府保护植物5种。植被类型主要有灌丛、次生性季风常绿阔叶林、红树林和海边沙滩植物群落等。蒲苔群岛... 详细信息

通过实地调查,对香港蒲苔群岛的植物物种多样性进行了研究。据统计蒲苔群岛共有维管束植物245种,隶属于93科203属,其中有国家及香港政府保护植物5种。植被类型主要有灌丛、次生性季风常绿阔叶林、红树林和海边沙滩植物群落等。蒲苔群岛植物区系以热带亚热带区系成分占优势。报导了蒲苔群岛各岛植物名录,并初步分析了各岛植物物种多样性的特点,同时对蒲苔群岛野生植物保育及旅游开发提出了建议。

关键词：蒲苔群岛物种多样性植被