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BTEX pollution caused by motorcycles in the megacity of HoChiMinh

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Journal of Environmental Sciences 2013年第2期25卷 348-356页

作者： Tran Thi ngoc lan Pham anh Minh University of Science Vietnam National University227 Nguyen Van CuHoChiMinh 70000Vietnam

Monitoring of benzene, toluene and xylenes （BTEX） was conducted along with traffic counts at 17 roadside sites in urban areas of HoChiMinh. Toluene was the most abundant substance, followed by p,m-xylenes, benzene, o-xylene and ethylbenzene. The maximum observed hour-average benzene concentration was 254 μg/m3 . Motorcycles contributed to 91% of the traffic fleet. High correlations among BTEX species, between BTEX concentrations and the volume of on-road motorcycles, and between inter-species ratios in air and in gasoline indicate the motorcycle-exhaust origin of BTEX species. Daily concentrations of benzene, toluene, ethylbenzene, p,m-xylenes and o-xylene were 56, 121, 21, 64 and 23 μg/m 3 , respectively. p,m-xylenes possess the highest ozone formation potential among the BTEX family.

关键词： air pollution benzene BTEX HoChiMinh motorcycle exhaust

*** human visual cortex responses to flickering light using functional near infrared spectroscopy and constrained ICA

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Journal of Innovative Optical Health Sciences 2014年第6期7卷 77-89页

作者： nguyen Duc Thang Vo Van Toi Le Giang Tran nguyen Huynh Minh Tam lan anh Trinh Biomedical Engineering Department International University Vietnam National Universities HCMCVietnam University of Saskatchewan Canada Electronics Engineering Department Posts and Telecommunications Institute of Technology Ho Chi Minh City Vietnam

The human visual sensitivity to the flickering light has been under investigation for *** finding of research in this area can contribute to the understanding of human visual system mechanism and visual disorders,and establishing diagnosis and treatment of *** aim of this study is to investigate the ffects of the flickering light to the visual cortex by monitoring the hemodynamic responses of the brain with the functional near infrared spectrosoopy(EnIRS)*** the acquired fnIRS signals are afected by physiological factors and measurement artifacts,constrained independent component analysis(eICA)was applied to extract the actual fnIRS responses from the obtained *** experimental results revealed significant changes(pnamic responses of the visual *** the baseline when the flickering stimulation was *** the uses of cICA,the contrast to noise ratio(CnR),reflecting the contrast of hemodynamic concentration between rest and task,became *** indicated the improvement of the nIRS signals when the noise was *** subsequent studies,statistical analysis was used to infer the correlation between the nIRS signals and the visual *** found that there was a slight decrease of the oxygenated hemoglobin con-centration(about 5.69%)over four frequencies when the modulation ***,the variations of oxy and deoxy-hemoglobin were not statistically significant.

关键词： Papillometre visual stimulation functional near infrared spectroscopy constrained independent component analysis

Antidiabetic and antioxidant activities of red seaweed Laurencia dendroidea

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Asian Pacific Journal of Tropical Biomedicine 2019年第12期9卷 501-509页

作者： The Han nguyen Thi Huyen nguyen Van Minh nguyen Thi lan Phuong nguyen Thi Van anh Tran anh Duy Do Sang Moo Kim Faculty of Food Technology Nha Trang University02 Nguyen Dinh Chieu StreetNha Trang CityKhanh HoaVietnam Quality Control Department Institute of Vaccines and Medical BiologicalsNha Trang CityKhanh HoaVietnam Faculty of Pharmacy University of Medicine and Pharmacy of Ho Chi Minh City41 Dinh Tien Hoang StreetHo Chi Minh CityVietnam Research Department of Marine Conservation Research Institute for Marine Fisheries224 Le Lai StreetHai Phong CityVietnam Department of Marine Food Science and Technology Gangneung-Wonju National University7 Jukheon-gilGangneung 25457Republic of Korea

Objective:To investigate antidiabetic and antioxidant activities of the extract and fractions from Vietnamese red seaweed Laurencia ***:The seaweed Laurencia dendroidea was extracted by using microwave-assisted extraction method in 80%*** seaweed extract was then fractionated using different solvents(n-hexane,chloroform,ethyl acetate,butanol and water).These obtained fractions were evaluated forα-glucosidase inhibitory and antioxidant *** activities were tested using DPPH,nitric oxide radical scavenging and metal chelating *** enzyme inhibition mode was determined using Lineweaver-Burk *** acidic and thermal stabilities,the ethyl acetate fraction was treated at pH 2.0 and 100℃,*** residual inhibitory activity of the fraction was calculated based on the initial inhibitory *** in vivo antidiabetic activity,mice were divided into four groups,including normal control,diabetic control,diabetic mice treated with ethyl acetate fraction and diabetic mice treated with *** glucose level of treated mice during acute and prolonged treatments was *** evaluate the toxicity of the ethyl acetate fraction,the body weight changes and activities of liver function enzymes(aspartate transaminase,alanine transaminase and gammaglutamyl transferase)were carried ***:The extract of Laurencia dendroidea showed strongα-glucosidase inhibitory and DPPH radical scavenging *** concentrations affected bothα-glucosidase inhibitory and antioxidant activities.A 80%aqueous methanol was the suitable solvent for extraction of enzyme inhibitors and *** solvent fractions,ethyl acetate fraction had the highest inhibitory activities againstα-glucosidase with a mixed type of inhibition and the strongest antioxidant activities,and was stable under acidic and thermal *** ethyl acetate fraction treated diabetic mice significantly reduced blood glucose level compare

关键词： α-Glucosidase inhibitor Antidiabetic Antioxidant Red seaweeds Vietnam

First Records of Megophrys daweimontis Rao and Yang, 1997 and Amolops vitreus(Bain, Stuart and Orlov, 2006)(Anura: Megophryidae, Ranidae) from Vietnam

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Asian Herpetological Research 2015年第1期6卷 66-72页

作者： Dzung Trung LE anh Van PHAM Son Hung lan nguyEn Thomas ZIEGLER Truong Quang nguyEn Faculty of Biology Hanoi National University of Education Faculty of Biology and Chemistry Tay Bac University AG Zoologischer Garten Kln Institute of Ecology and Biological Resources Vietnam Academy of Science and Technology

Two amphibian species,Megophrys daweimontisandAmolops vitreus,are recorded for the ifrst time from Vietnam, on the basis of a new amphibian collection from Dien Bien and Son La provinces. In addition, acoustic analysis ofA. vitreus is also provided based on the advertisement calls recorded in Muong nhe nature Reserve of Dien Bien Province, Vietnam.

关键词： Amolops vitreus Megophrys daweimontis new records advertisement call Dien Bien Province Son La Province

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FDI对越南企业发展的影响研究

FDI对越南企业发展的影响研究

作者：阮维英（nguy(?)n Duy anh）东华大学

学位级别：硕士

国际贸易与外商直接投资是两种重要的国际经济关系,传统上,人们将国际贸易与外商直接投资视作两种不同的经济现象,并分别加以研究。但是随着经济全球的日益深入,二者之间联系越来越密切,表现出相互促进和相互补充的交叉发展特征。20世... 详细信息

国际贸易与外商直接投资是两种重要的国际经济关系,传统上,人们将国际贸易与外商直接投资视作两种不同的经济现象,并分别加以研究。但是随着经济全球的日益深入,二者之间联系越来越密切,表现出相互促进和相互补充的交叉发展特征。20世纪80年代中期,越南实施“改革开放“的新政策,选择了积极融入世界经济体系和广泛与经济全球化的发展战略。25年来,大力吸引外国直接投资成为了越南开展对外经贸合作的重要部分。随着越南改革开放的不断深化,大量外资涌入越南。FDI的流入对越南的经济发展产生了广泛而深刻的影响,尤其08年金融危机爆发后,FDI的变已经成为影响越南经济波动的重要外部因素。FDI通过改变一国的信贷约束和资产价格影响企业的投资和生产决策行为,并通过金融加速器效应,引进经济的大幅波动。作为一名在华越南留学生,在企业管理专业研究生求学期间开始关注FDI对越南企业发展的影响问题,并将作为学位论文展开研究,形成论文.主要研究两个方面：研究越南的FDI通过对越南企业进出口的影响和FDI对于越南国内企业管理运营的影响。并且本人得出总体结论、第一：FDI在越南体现了显著的贸易创造效应。相比之下,越南内资企业的对外贸易总量则处于停滞不前的状态。总之FDI通过它的资本投入、技术投入、提升了越南贸易产品的国际竞争力,迅速扩展了国际市场空间。第二：外资给合资企业带来的新技术并没有对提高越南的国际竞争力做出最大贡献,越南利用外资来获得先进技术和由先进技术确定的竞争力提高的目的并没有完全实现。

关键词： [越南] [外商直接投资] [对外贸易] [企业管理]

B2C类型网站购物体验对购买意愿的影响研究——以成都地区来华留学生为例

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B2C类型网站购物体验对购买意愿的影响研究——以成都地区来华留...

作者： CAP THI lan anh 西南交通大学

学位级别：硕士

自从中国改革开放以来,来华外国人越来越多,他们已经成为消费者中不可忽视的一个群体。来华留学生作为其中一个特殊群体,一直都有学者对其进行研究,但是多数研究还是停留在来华学习动机和跨文化适应问题上,几乎没有学者对于来华留学生... 详细信息

自从中国改革开放以来,来华外国人越来越多,他们已经成为消费者中不可忽视的一个群体。来华留学生作为其中一个特殊群体,一直都有学者对其进行研究,但是多数研究还是停留在来华学习动机和跨文化适应问题上,几乎没有学者对于来华留学生的网络购物体验状况进行实证研究。而中国要想真正的成为一个包容万物的大国,就必须重视外国人在中国的网络购物体验。本研究通过调查39个国家和地区的来华留学生,基于“刺激—机体—反应”(S-O-R)模型,结合强化理论和期望理论,从消费者心理学的角度,对来华留学生群体在B2C类型网站上的顾客体验状况进行调查。同时,以成都来华留学生群体为调查样本,探索顾客体验对购买意愿的影响,消费情绪在顾客体验与购买意愿之间的中介作用,以及顾客价值倾向对购物体验、消费情绪、购买意愿之间关系的调节作用。运用层次分析法进行数据分析发现:(1)顾客体验对购买意愿有显著正向影响。(2)顾客体验对积极情绪有显著正向影响;对消极情绪有显著负向影响。(3)积极情绪在顾客体验与购买意愿的关系中起到部分中介作用。(4)情感价值倾向在顾客体验与积极情绪之间起到正向调节作用;功能价值倾向在顾客体验与购买意愿之间起到正向调节作用。具体而言,当顾客的情感价值倾向水平越高,良好的顾客体验产生的积极情绪越多;反之,越少。当顾客的功能价值倾向水平越高,顾客体验与购买意愿之间的正向相关关系更强。本文开启了对来华留学生的消费体验和行为的探索与研究。本文的研究结果可以为中国各类网络购物网站的发展完善提供指导建议,有利于中国电子商务企业为国外用户打造一个更有吸引力的消费平台。另一方面,本研究也启发中国企业在考虑用户感受的时候,需要适当地考虑外国用户,为中国企业更快更好地走向世界做好铺垫。最后,本文还总结分析了本研究的局限性,并指出未来的研究可以从顾客体验和购买意愿的跨文化对比研究、以及消费情绪研究方面进行积极探索。

关键词：来华留学生顾客体验消费情绪购买意愿顾客价值倾向

汉越词对汉语教学的影响与教学策略——以《汉语教程》（第一册上、下）为例

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汉越词对汉语教学的影响与教学策略——以《汉语教程》（第一册上...

作者：段氏兰英（Doàn Th(?) lan anh）东北师范大学

学位级别：硕士

语言是文化最重要的载体,也是文化重要的组成部分。但任何一种语言的词汇系统不可能是完全封闭的,因为它们很难自足。再说,在交流过程中非靠语言不可。所以,在交流时所需要的语言需要接纳和吸收词汇来丰富自己,补充不足的地方,使语言能... 详细信息

语言是文化最重要的载体,也是文化重要的组成部分。但任何一种语言的词汇系统不可能是完全封闭的,因为它们很难自足。再说,在交流过程中非靠语言不可。所以,在交流时所需要的语言需要接纳和吸收词汇来丰富自己,补充不足的地方,使语言能不断地新陈代谢,使表达更精彩、更完善。中越两国的之间关系,大概是从公元前二世纪就已经开始了。这证明了越南在很多方面都受到过中国的影响。特别是语言,以前越南是一个落后的国家,没有文字,因此在两国间的交流中,大量的汉语词传到了越南,然后被越南人吸收、融合并使用。到现在,越南语里有一部分词是汉越词,这些词就是从汉语词汇借过来的,并受到越南的影响而发生改变,成为越南语不可缺少的一部分。从此,越南人在学习汉语过程中最感兴趣的问题就是汉越词,也就是说汉越词对越南学习者既有利又有弊。因为有不少汉越词发展到现在,在词义、用法上已经改变或消失。但本人认为,如果能够充分地利用汉越词与汉语词在词义方面的异同点来教越南学习汉语的人,就可以让他们快速掌握汉语词的意义和用法。所以,我把汉越词与汉语词对比分析作为研究对象。同时在越南语里找出汉越词对越南学习者的正迁移和负迁移,并指出汉越词会给越南学生带来的影响。从而帮助学生认出自己不足的地方,找到学习方法,并且帮助老师调整教学内容和教学方法以及如何克服学生偏误的方法。

关键词：汉越词影响正迁移负迁移教学

Evaluation of Interaction between Surface Water and Groundwater in the South of Hanoi City by Stable Isotope Technique

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Journal of Environmental Protection 2022年第11期13卷 870-880页

作者： Vo Thi anh Tran Khanh Minh Ha lan anh Mai Dinh Kien Vu Hoai Dang Duc nhan Institute for nuclear Science and Technology Hanoi Vietnam

The δ18O and δ2H stable isotope techniques for studying properties of groundwater and surface help us to understand more clearly about the distribution and movement of groundwater in the South of Hanoi area. There were 68 water samples from the studying area and analyzed by a Liquid Water Isotope Analyzer (LWIA-24D). The stable isotope values of the groundwater from Pleistocene aquifers were range from -3.21‰ to -9.55‰ δ18O and -35.32‰ to -67.44‰ δ2H;rainwater from -8.18‰ to -4.13‰ δ18O and -61.19‰ to -17.93‰ δ2H;Red river water from -7.51‰ to -5.29‰ δ18O and -51.60‰ to -38.99‰ δ2H. Based on stable isotope characteristics, the results show that there was a relationship between surface water and groundwater in the South of Hanoi city. It is that groundwater recharges for river water in the dry season with 74%, and in the rainfall season groundwater is recharged from river with 87%.

关键词： Stable Isotopes Groundwater Surface Water River Water Precipitation Recharge

Assesment of Frequency-Magnitude of Extreme Rainfall Events-Case Study of the MeKong River Delta

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Journal of Environmental Science and Engineering(B) 2015年第3期4卷 161-168页

作者： Pham Hai An Tran anh Tu Tran Dinh lan nguyen ngoc Tien Institute of Marine Environment and Resources VAST Haiphong 180000 Vietnam Institute of Marine Geology and Geophysics VAST Hainoi 1000000 Vietnam

Extreme rainfall events are primary natural hazards, which cause a severe threat to people and their properties in populated cities, which are normally located in coastal areas in Vietnam. Analysing these events by using a data series observed over years will support us to draw a picture of how the climate change impact on local environments. The purpose of this report is to understand the characteristics of the extreme rainfall events in MEKOnG river delta （south Vietnam）. Daily rainfall data in the period of 30 years for a meteorological station in each area were collected from the Vietnam national Hydro-meteorological Service. The extreme rainfall events were defined as those exceeding the 95th percentile for each station. The analytical results show that the rainfall values （95th percentile） are 37.4 mm/day at nam Can station, 27 mm/day at My Thanh station, 22.4 mm/day at Hoa Binh station, 23.8 mm/day at Binh Dai station and 22.7 mm/day at Ben Trai station. The highest rainfall data ever recorded are 246.4 mm/day （nam Can）, 174.5 mm/day （My Thanh）, 179 mm/day （Hoa Bin_h）, 187.3 mm/day （Binh Dai） and 136.3 mm/day （Ben Trai） during 1983-2012. The result of the Mann-Kendall tests show that there was a significant creasing of the rainfall at nam Can, My Thanh station in two periods （1983-2012, 1998-2012） while no clear trend of the rainfall was recoreded at Hoa Birth, Binh Dai, Ben Trai station. In order to estimate the return period of the extreme rainfall events, the method General Extreme Value Distribution was used to calculate frequent distribution. The magnitudes of daily maximum rainfall were from 2 to 100 years. The results of return period show that maximum rainfalls are 46.6 mm at nam Can station （highest） and 31.4 mm at Hoa Birth station （lowest） during 50 years. Similarly, maximum rainfalls are expected to be about 55.1 mm at nam Can station and 37.2 mm at Hoa Birth station for 100 years.

关键词： Generalized extreme value distribution MEKOnG river delta.