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红松人工林和相邻次生林林下红松天然更新种群格局分析

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森林工程 2018年第2期34卷 16-20页

作者：王琴香沈海龙和春庭 nguyen Thanh tuan 东北林业大学林学院哈尔滨150040 云南省怒江傈僳族自治州林业局云南怒江673200 越南林业大学第二分校林学系越南同奈810000

为了探讨球果采摘后红松天然更新幼苗幼树的生长生存现状,了解红松天然更新种群的动态,以红松人工林及其相邻蒙古栎次生林两种林分为对象,对红松天然更新幼苗幼树的分布状态及其生长状况进行了调查分析。结果表明:(1)红松人工林与蒙古... 详细信息

为了探讨球果采摘后红松天然更新幼苗幼树的生长生存现状,了解红松天然更新种群的动态,以红松人工林及其相邻蒙古栎次生林两种林分为对象,对红松天然更新幼苗幼树的分布状态及其生长状况进行了调查分析。结果表明:(1)红松人工林与蒙古栎次生林林内红松天然更新种群年龄结构都不完整,蒙古栎次生林内红松天然更新种群年龄对应于球果采摘强度的不同时期出现了两个峰值,而红松人工林内只有前4年生幼苗;(2)两种林分中1~3a红松天然更新幼苗的株/簇与簇数均符合指数函数变化,即红松幼苗幼树多以单株存在,簇生幼苗的数量占比很少;(3)蒙古栎次生林林内的红松天然更新幼苗在苗高和地径生长都比红松人工林内的具有优势,两种林分中1a和2a更新幼苗的苗高差异不明显,但3a更新幼苗的苗高差异显著;次生林内1~3a红松天然更新幼苗的地径均极显著高于人工林林内的红松幼苗。结论:在当前的这种球果采摘条件下,红松人工林及其相邻蒙古栎次生林林内红松更新幼苗幼树分布受到了很大影响,种群年龄结构不合理,大多数幼苗幼树以单株存在。

关键词：红松球果采摘天然更新簇/株生苗分布格局

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阮俊:记忆在燃烧

艺术与设计 2023年第4期1卷 134-137页

作者：哲洛阮俊(图) 不详

越南裔艺术家阮俊(tuan Andrew Nguyén)近年频频亮相诸多国际性艺术大展。他1976年出生于越南西贡,三岁时因越战随家人移民美国并在加利福尼亚州长大。大学期间,他开始定期回到越南,并在2004年完成学业后决定搬回故乡。此时的西贡早已... 详细信息

越南裔艺术家阮俊(tuan Andrew Nguyén)近年频频亮相诸多国际性艺术大展。他1976年出生于越南西贡,三岁时因越战随家人移民美国并在加利福尼亚州长大。大学期间,他开始定期回到越南,并在2004年完成学业后决定搬回故乡。此时的西贡早已更名为胡志明市。在这里,他联合创立螺旋奖团体(The Propeller Group)。该艺术小组伪装成广告代理公司,探究当代越南语境下资本主义广告和共产主义宣传的矛盾及重叠。同一时期,他还主导组织起非营利空间“圣艺术”(San Art,San意味着展演平台),发起展览、阅读室、教育工作坊等形态多样的公共项目。

关键词：广告代理公司工作坊加利福尼亚州公共项目胡志明市非营利

State Policy on the Environment in Vietnamese Handicraft Villages

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Chinese Business Review 2016年第6期15卷 290-295页

作者： nguyen Thi Thu Huong Hanoi Open University Hanoi Vietnam

Handicraft villages play an important role in promoting social and economic development in rural areas as well as Vietnam＇s economy. Nowadays, Vietnam＇s handicrafts have a foothold in the world market, and are exported over 163 countries and territories （tuan, 2010）. However, the production activities of the handicraft village have a lot of shortcomings, especially the problem of environmental pollution （Chi, 2010）. Therefore, government policy plays a very important role to minimize environmental pollution villages, contributing to improving environmental quality and public health. This paper focuses on： 1）. Current status of state policy environment in handicraft villages shows the achievements and limitations of the policy, from which reviews state policy in environments in handicraft villages （through fieldwork in the handicraft villages）; and 2）. Solution to improve state policy on environmental protection in handicraft villages in Vietnam.

关键词： craft village state policy environmental policy

Research to Establish a Set of Combinatorial Indicators to Calculate Flood Vulnerability Index in Thach Han-Ben Hai River Basin, Quang Tri Province, Vietnam

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Journal of Environmental Science and Engineering(B) 2021年第4期10卷 138-150页

作者： Ngo Chi tuan nguyen Thanh Son nguyen Kien Dung Can Thu Van University of Science Vietnam National UniversityHanoi 1000000Vietnam Hanoi University of Natural Resources and Environment Hanoi 1000000Vietnam Ho Chi Minh City University of Natural Resources and Environment Ho Chi Minh City 700000Vietnam

In recent times,approaches to flood prevention and mitigation have changed a *** changes are to shift the focus from flood control to flood risk management,in which the assessment of vulnerability to floods caused by each sector and field corresponding to each flood magnitude is *** flood vulnerability assessment studies are basically holistic based on factors affected by floods or in aspects:economy,society and ecological environment,and aspects that are mentioned in all areas of social *** content of the flood vulnerability assessment method usually considers 3 components:E(Exposure),S(Susceptibility),A(Adaptability-Recovery).Each component will contain many different variables belonging to different objects and different natural-economic-social characteristics in each ***,for each research area,the evaluation method needs to establish an appropriate set of indicators.A set of indicators used to assess flood vulnerability must:be scientific;be practical;simplify the investigation,collection and synthesis of *** study has established a set of combinatorial indicators including 27 indicators for the T-BRB(Thach Han-Ben Hai River Basin)on the basis of analysis and synthesis from case studies.

关键词： Vulnerability combine indicators T-BRB

Research and Experimental Application of Empirical Formulas to Calculate Riverbank Erosion in Tien River in the Mekong Delta

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Journal of Environmental Science and Engineering(A) 2021年第3期10卷 116-123页

作者： Can Thu Van nguyen Thanh Son Ngo Chi tuan Ho Chi Minh City University of Natural Resources and Environment Ho Chi Minh City 700000Vietnam University of Science Vietnam National UniversityHo Chi Minh City 700000Vietnam

In recent years,the problem of riverbank and coastal erosion in the MD(Mekong Delta)is very complicated;landslides occur in most of the inland and coastal *** riverbank landslides occur gradually,but in contrast to sudden landslides that cause great damage,occur with increasing *** shows that the trend of riverbank erosion will be more complicated and more frequent,especially in the context of extreme weather changes and changes in hydrological regime in the next *** from the authorities show that,if in 2010 the whole region had nearly 100 landslide points;by 2020 it had increased to more than 680 points;in which Dong Thap in the Tien River is one of the two localities with the most serious riverbank ***,there are many methods used to assess and forecast the level of riverbank erosion in specific areas,such as:method of document analysis,measurement data;physical model;mathematical models and empirical *** this study,the empirical formula is used to calculate the landslide level for the Tien River section in Cao Lanh,Dong Thap *** calculation results according to the empirical formula have a certain agreement with the actual data,the correlation coefficient is 0.90 and the Nash coefficient is 0.78,the relative error of less than 15%is 80%of the *** results have shown the possibility of applying empirical formulas to establish and calculate for other landslide areas along the banks of Hau River and MD.

关键词： Riverbank erosion MD empirical formula for calculating bank erosion

Finite Element Modeling in Analyzing Physical Properties of the Pb-Free Piezoelectric Materials

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材料科学与工程（中英文A版） 2013年第4期3卷 282-288页

作者： Vo Thanh Tung nguyen Trong Tinh nguyen Hoang Yen Le Thi Ngoc Bao Dang Anh tuan Hue University of Science Hue University Hue City 08454 Vietnam Institute of Applied Physics and Scientific Instrument of Vietnamese Academy of Science and Technology 08404 Vietnam

New giant piezoelectric factor materials such as PZT, PZN-PZT, PMN-PT and PZN-PT etc. were researched during the last decade and are actually becoming commercially available. However, there is an urgent demand for high performance Pb-free piezoelectric to substitute for the current workhorse, the PZT family. Recently, many Pb-free systems have been reported that shows equally as excellent piezoelectricity as materials in PZT family at room temperature. In this present study, it uses the Finite Element modeling (FEM method) with the simulation program to compare the physic properties of piezoceramics in PZT family and Pb-free piezoceramic Ba(Zr0.2Ti0.8)O3-50(Ba0.7Ca0.3)TiO3 (BZT-50BCT) and show the advantage properties of BZT-50BCT. Furthermore, the results will be a premise of using the simulation method in researching the properties of new piezoelectric materials to shorten time as well as save money and time.

关键词：无铅压电材料有限元建模物理性能建模分析 PZN-PZT 无铅压电陶瓷 PMN-PT 压电系数

汇率对越中双边贸易的影响:基于自回归分布滞后模型的研究结果

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中国-东盟研究 2019年第2期 49-81页

作者：范英俊陈氏霞阮孟雄王海峰(译) 蓝珊珊(译) 越南社会科学院世界经济和政治研究所越南社会科学院世界经济和政治研究所国际经济部越南胡志明国家政治学院广西大学国际学院

本文通过采用自回归分布滞后模型(ARDL),探讨越南盾/人民币汇率(包括汇率水平和波动性)对越中两国贸易的影响。分解模型结果表明,9种越南对中国的进口商品(约占进口总额的28.67%)对越南盾/人民币实际汇率水平的变化十分敏感。9种越南对... 详细信息

本文通过采用自回归分布滞后模型(ARDL),探讨越南盾/人民币汇率(包括汇率水平和波动性)对越中两国贸易的影响。分解模型结果表明,9种越南对中国的进口商品(约占进口总额的28.67%)对越南盾/人民币实际汇率水平的变化十分敏感。9种越南对中国的出口商品(约占出口总额的39.15%)也随汇率水平的变化而变化。大多数未受汇率波动影响的进出口商品是原材料、中间品和简单加工的产品。另外,聚合模型的结果表明,汇率与贸易之间没有联系。换句话说,汇率不太可能成为促进中越贸易平衡的有效工具。这将为越南的货币和贸易政策之间的有效协调提供经验依据。

关键词：贸易赤字汇率进出口中国越南

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越南安息香的低温半致死温度与抗寒适应性

林业科技开发 2014年第3期28卷 22-26页

作者：阮俊阳刘新亮郁万文曹福亮南京林业大学森林资源与环境学院南京210037 越南北江农林大学

以越南河内(Hanoi)、江西吉水(Jishui)、湖南资兴(Zixing)3个产地1年生越南安息香幼苗为试材,采用人工模拟低温处理技术进行低温处理,测定电解质外渗率,并配合Logistic方程对不同产地枝条的半致死温度(LT50)进行了拟合;测定低温处理下... 详细信息

以越南河内(Hanoi)、江西吉水(Jishui)、湖南资兴(Zixing)3个产地1年生越南安息香幼苗为试材,采用人工模拟低温处理技术进行低温处理,测定电解质外渗率,并配合Logistic方程对不同产地枝条的半致死温度(LT50)进行了拟合;测定低温处理下各产地越南安息香的MDA含量、根系活力,并观察不同产地越南安息香1年生幼苗的恢复情况。结果表明,3个产地越南安息香耐低温能力差异显著,半致死温度值LT50在-14.93^-9.48℃之间,抗寒性强弱排序依次为:Zixing>Jishui>Hanoi;幼苗叶片MDA含量、根系活力及抽条指数均反映出产地抗寒性强弱与半致死温度基本一致。

关键词：越南安息香 Logistic方程 MDA含量根系活力抗寒性

不同偏高岭土掺量对板岩骨料碱活性抑制效果研究

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中文科技期刊数据库（全文版）工程技术 2016年第11期 306-306页

作者： nguyen VAN tuan 李固华 tran NGOC LONG 俞云龙李文强西南交通大学土木工程学院四川成都610031中国荣大学土木工程学院乂安省荣市3855269越南

采用板岩快速砂浆棒法研究了偏高岭土对板岩碱活性的抑制效果。并比较了偏高岭土掺量0%;10%;15%;20%;25%;30%;40%;50%对ASR的抑制效果。试验结果表明:当使用等质量偏高岭土代替水泥;在替换掺量不小于20%时;其20%的偏高岭土28d膨胀率已等... 详细信息

采用板岩快速砂浆棒法研究了偏高岭土对板岩碱活性的抑制效果。并比较了偏高岭土掺量0%;10%;15%;20%;25%;30%;40%;50%对ASR的抑制效果。试验结果表明:当使用等质量偏高岭土代替水泥;在替换掺量不小于20%时;其20%的偏高岭土28d膨胀率已等于0.041%;其对碱硅酸反应(ASR)的抑制已满足耐久性要求。不过当继续增大偏高岭土含量时;虽然各龄期的试件膨胀率效果更好;但是膨胀率亦相差不大。

关键词：偏高岭土掺量碱硅酸反应快速砂浆棒法