检索结果-南通市图书馆

Compensation of Zn substitution and secondary phase controls effective mass and weighted mobility in In and Ga co-doped ZnO material

引用

Journal of Materiomics 2021年第4期7卷 742-755页

作者： Oanh Kieu Truong Le Anh tuan Thanh Pham Ngoc Kim Pham trang Huyen Cao Pham Truong Huu nguyen Dung Van Hoang Hanh Kieu Thi Ta Dai Cao Truong Hoa Thi Lai Thuy Dieu Thi Ung Vinh Cao tran Thang Bach Phan aboratory of Advanced Materials University of ScienceHoChiMinh City700000Viet Nam Vietnam National University HoChiMinh City700000Viet Nam Faculty of Physics and Engineering Physics University of ScienceHoChiMinh City700000Viet Nam Faculty of Materials Science and Technology University of ScienceHoChiMinh City700000Viet Nam Center for Innovative Materials and Architectures(INOMAR) HoChiMinh CityViet Nam Institute of Materials Science Vietnam Academy of Science and TechnologyHanoi100000Viet Nam

Conductivity s and thermal conductivity k are directly related to carrier concentration while Seebeck coefficient S is inversely proportional to carrier ***,improving thermoelectric(TE)performance is ***,the first-time analysis of secondary phase-controlled TE performance in terms of density-of-state effective mass m*d,weighted mobility mw and quality factor B is discussed in ZnO *** results show that the secondary spinel phase Ga2O_(3)(ZnO)9 not only impacts on k but also on s and S at high temperature,while the effect of carrier concentration seem to be dominant at low *** the high-spinel-segregation sample,a compensation of dopant atoms from the spinel to substitutional sites in the ZnO matrix at high temperature leads to a low decreased rate of temperaturedependent m**** compensation process also induces a band sharpening,a small mw reduction,and a large B *** a result,In and Ga co-doped ZnO bulk with the highest spinel segregation achieves the greatest PF improvement by 112.8%,owing to enhanced Seebeck coefficient by 110%as compared to the good Zn-substitution sample.

关键词： Thermoelectrics In and Ga co-Doped ZnO Secondary phase Zn substitution DOS effective Mass Weighted mobility

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

汉语和越南语集合量词对比研究

汉语和越南语集合量词对比研究

引用

作者：陈阮俊雨(nguyen tuan Vu tran) 上海师范大学

学位级别：硕士

量词是汉语和越南语词汇中的一个丰富而复杂的大类,无论是在汉语还是在越南语中,量词的数量都较多、使用频率较高,而且用法也都相当复杂,在汉越词汇中都占有重要地位。汉越语量词的名称存在一点差别,越语把“量词”称为“类词”,但在性... 详细信息

量词是汉语和越南语词汇中的一个丰富而复杂的大类,无论是在汉语还是在越南语中,量词的数量都较多、使用频率较高,而且用法也都相当复杂,在汉越词汇中都占有重要地位。汉越语量词的名称存在一点差别,越语把“量词”称为“类词”,但在性质与用法上跟汉语的量词相同(为了方便研究,本文把越语“类词”称为“量词”)。量词的独特语义与用法特征逐渐得到了国内外语言学界的关注,进行了很多与此有关的研究,并提出了许多的宝贵的理论成果。现代汉语把量词分为三大类:名量词、动量词、复合量词。名量词又分为六类:个体量词、集合量词、部分量词、度量衡量词、容器量词、临时量词,其中集合量词是本文研究的重点。本文将“汉语集合量词”与“越南语集合量词”作为本文研究对象。汉语集合量词使用频率比越南语高,研究成果也更加全面,而越南语集合量词目前的研究成果还不够成熟。虽然汉越语两种语言的集合量词具有很多共同之处,但是汉越两语的语言系统各有特色,它们之间仍存在许多差异,这一点给学习汉语的越南学生造成较大的障碍。本文在前辈对量词研究的基础上将汉越语集合量词进行具体分析与对比研究,找出汉越语集合量词之间的异同点,让越南留学生深入领会汉越集合量词的语义与句法功能,希望能够为学汉语的越南学生、学越南语的中国学生提供一份学习及研究集合量词的参考资料。本文研究主要的内容:说明本文的研究对象和选题意义,整理汉越语量词的定义与分类,说明与本文研究相关的基本概念,介绍与本文论题有关的研究现状,对本文的研究对象作了定量分析,并阐明了本研究使用的理论与方法。本文对汉语和越南语集合量词的组合能力进行对比,考察两种语言的集合量词跟数词、指示代词、形容词的差异。并对汉越集合量词重叠形式进行比较,以此作为基础进一步考察它们句法意义和句法功能之间的差异。本文对汉语和越南语集合量词“堆”与“??ng”、“副”与“b?”进行个案研究,主要是考察汉语量词“堆”与“副”的产生及其历史演变,然后从它们的语义特征、计量的对象与语义色彩对汉越语两种语言进行比较。

关键词：汉越集合量词 “堆”与“??ng” “副”与“b?”

来源：

同方学位论文库评论

在线全文

同方学位论文库

学校读者我要写书评

暂无评论

Optimum Determination of Partial transmission Ratios of Mechanical Driven Systems Using a V-belt and a Three-Step Helical Gearbox

引用

Journal of Environmental Science and Engineering(B) 2017年第6期6卷 328-331页

作者： Dang Anh tuan nguyen Khac tuan Vu Ngoc Pi Mechanical Engineering Faculty Thai Nguyen University of Technology Thai Nguyen 23000 Vietnam Automotive and Power Machinery Faculty Thai Nguyen University of Technology Thai Nguyen 23000 Vietnam

This paper introduces a new study on the optimum calculation of partial transmission ratios of a mechanical drive system using a V-belt and a three-step helical gearbox in order to get the minimum size of the system. The chosen objective function was the cross section dimension of the system. In solving the optimization problem, the design equation for pitting resistance of a gear set was investigated and equations on moment equilibrium condition of a mechanic system including a V-belt and three helical gear units and their regular resistance condition were analysed. From the results of the study, effective formulas for determination of the partial ratios of the V-belt and three-step helical gearboxes were introduced. As using explicit models, the partial ratios can be determined accurately and simply.

关键词： transmission ratio gearbox design optimum design V-belt drive helical gearbox.

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Optimum Determination of Partial transmission Ratios of Three-Step Helical Gearboxes for Getting Minimum Cross Section Dimension

引用

Journal of Environmental Science and Engineering(A) 2016年第11期5卷 570-573页

作者： Vu Ngoc Pi nguyen Khac tuan Thai nguyen University of Technology Thai Nguyen 23000 Vietnam

This paper presents a new study on optimum calculation of partial ratios of three-step helical gearboxes. The chosen objective function is the cross section dimension of the gearbox. In solving the optimization problem, the design equation for pitting resistance of a gear set was investigated and equations on moment equilibrium condition of a mechanic system including three gear units and their regular resistance condition are analyses. From the results of the study, effective formula for determination of the partial ratios of three-step helical gearboxes is introduced. As the formulas are explicit, the partial ratios can be calculated accurately and simply.

关键词： Gearbox design optimum design helical gearbox transmission ratio.

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Adaptive Gaussian Noise Image Removal Algorithm Using Filtering-Based Noise Estimation

引用

Journal of Measurement Science and Instrumentation 2011年第3期2卷 230-234页

作者： tuan-anh nguyen Hong-son nguyen Min-cheol HONG Dept.of Information and Telecommunication Soongsil University

This paper proposes a spatially denoising algorithm using filtering-based noise estimation for an image corrupted by Gaussian *** proposed algorithm consists of two stages:estimation and elimination of noise *** adaptively deal with variety of the noise amount,a noisy input image is firstly filtered by a lowpass *** deviation of the noise is computed from different images between the noisy input and its filtered *** addition,a modified Gaussian noise removal filter based on the local statistics such as local weighted mean,local weighted activity and local maximum is used to control the degree of noise *** show the effectiveness of the proposed algorithm.

关键词： denoising local statistics Gaussian filtering noise estimation Gaussian noise

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

VINACONEX公司进出口业务部发展战略研究

VINACONEX公司进出口业务部发展战略研究

引用

作者： nguyen tuan HAI 北京工业大学

学位级别：硕士

当今世界,不论是发达国家还是发展中国家,企业战略都显得很重要,因为它能够结局影响企业未来发展最重要、最基本的问题。越来越多的企业开始重视对企业发展战略的建立,如果企业在战略目标的制定和执行中出现失误,必然会导致企业发展受... 详细信息

当今世界,不论是发达国家还是发展中国家,企业战略都显得很重要,因为它能够结局影响企业未来发展最重要、最基本的问题。越来越多的企业开始重视对企业发展战略的建立,如果企业在战略目标的制定和执行中出现失误,必然会导致企业发展受阻甚至导致企业破产。每个国家都需要以出口贸易作为与世界互动发展的活动,一方面能够为世界各国提供需要的产品,另一方面则是能为国内提供相关的工作机会。其中,世界上出口贸易方面比较强大的国家有中国、美国、日本、韩国、德国等。这些国家的经济之所以强大是因为拥有强大的经济进出口基础。由此可见,就国家层面来说,发现、推广并进出口自己的优势领域产品就等于把握了经济发展的关键。近年,越南已有不少国家企业正在转变成股份公司,加之要想加入WTO又有较高的门槛,面对竞争日益激烈的压力,国有企业不能像以前一样继续实施补贴,必须改变发展战略。如将国有企业尽量地股份化或者进行破产处理。因此,要想使得本国企业得到很好的发展,在当今世界经济的发展形势下,就必须尽快做好企业战略规划,发现、推广并进出口本国的优势领域产品。本文选取已经实现股份化的国家公司代表VINACONEX公司,该公司较之于之前的发展战略已经有了很大的改变。本文对VINACONEX公司的背景、发展战略、战略管理实践进行研究,其中,重点介绍企业的发展战略。研究过程中,运用SWOT战略分析工具,采用了企业宏观环境的PEST分析为VINACONEX公司制定了新的发展战略。另外,本文使用波特无力魔性分离为VINACONEX公司提出了发展战略的实施对策。本文在研究过程中力求紧密联系实际。切实关注战略实施的可造作性。本文对进出口行业具有参考价值。

关键词： SWOT分析进出口发展战略

来源：

同方学位论文库评论

在线全文

同方学位论文库

学校读者我要写书评

暂无评论

Optimum Determination of Partial transmission Ratios of Mechanical Driven Systems Using a V-belt and a Helical Gearbox with Second-Step Double Gear-Sets

引用

Journal of Environmental Science and Engineering(A) 2017年第7期6卷 377-380页

作者： nguyen Khac tuan Vu Ngoc Pi Automotive and Power Machinery Faculty Thai Nguyen University of Technology Thai Nguyen 23000 Vietnam Mechanical Engineering Faculty Thai Nguyen University of Technology Thai Nguyen 23000 Vietnam

This paper presents a study on the optimum determination of partial transmission ratios of a mechanical drive system using a V-belt and a helical gearbox with second-step double gear-sets in order to get the minimum size of the system. The chosen objective function was the cross section dimension of the system. In the optimization problem, the design equation for pitting resistance of a gear set was investigated and equations on moment equilibrium condition of a mechanic system including a V-belt and a helical gearbox with second-step double gear-sets and their regular resistance condition were analysed. Based on the results of the study, effective formulas for calculation of the partial ratios of the V-belt and a helical gearbox with second-step double gear-sets were proposed. By using explicit models, the partial ratios can be determined accurately and simply.

关键词： transmission ratio gearbox design optimum design V-belt drive helical gearbox.

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Empirical Equilibrium Beach Profiles Along the Eastern Tombolo of Giens

引用

Journal of Marine Science and Application 2018年第2期17卷 241-253页

作者： Minh tuan Vu Yves Lacroix Viet Thanh nguyen SEATECH University of Toulon83162 La Valette-du-VarFrance University of transport and Communications Hanoi 100000Vietnam MEMOCS UniversitàDegli Studi dell’Aquila67100 L’AquilaItaly

Beaches along the eastern branch of the Giens double tombolo are subject to coastal *** of the behavior of the beach profile configuration in response to natural and anthropogenic changes using the concept of equilibrium beach profile(EBP)could be useful in finding the most suitable measure to address the erosion *** investigation data of 11 beaches along the eastern tombolo were supplied for this study,and a nonlinear fitting technique was applied to estimate the best parameter values of seven empirical formulations of the relevant *** of the observed beach profiles could be described by a single function,but a single EBP was inadequate to represent all of the beach profiles *** variation found could be explained in terms of longshore variation of bathymetry,sediment size,and wave *** of the validity of the EBPs revealed that a representative EBP of each beach is governed by different equilibrium parameters.

关键词： Equilibriumbeachprofile EasterntomboloofGiens Exponentialfunction Logarithmicfunction Potentialfunction,erosion,and accretion

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Ethanol extracts of Scutellaria baicalensis protect against lipopolysaccharide-induced acute liver injury in mice

引用

Asian Pacific Journal of Tropical Biomedicine 2015年第9期5卷 733-738页

作者： Hai nguyen Thanh Hue Pham Thi Minh tuan Anh Le Huong Duong Thi Ly Tung nguyen Huu Loi Vu Duc Thu Dang Kim Tung Bui Thanh School of Medicine and Pharmacy Vietnam National University Hanoi University of Pharmacy

Objective: To investigated the protective potential of ethanol extracts of Scutellaria baicalensis(S. baicalensis) against lipopolysaccharide(LPS)-induced liver injury. Methods: Dried roots of S. baicalensis were extracted with ethanol and concentrated to yield a dry residue. Mice were administered 200 mg/kg of the ethanol extracts orally once daily for one week. Animals were subsequently administered a single dose of LPS(5 mg/kg of body weight, intraperitoneal injection). Both protein and m RNA levels of cytokines, such as tumor necrosis factor alpha, interleukin-1β, and interleukin-6 in liver tissues were evaluated by ELISA assay and quantitative PCR. C yclooxygenase-2, inducible nitric oxide synthase, and nuclear factor-κB protein levels in liver tissues were analyzed by western blotting. Results: Liver injury induced by LPS signifi cantly increased necrosis factor alpha, interleukin-1β, interleukin-6, cyclooxygenase-2, inducible nitric oxide synthase, and nuclear factor-κB in liver tissues. Treatment with ethanol extracts of S. baicalensis prevented all of these observed changes associated with LPS-induced injury in liver ***: Our study showed that S. baicalensis is potentially protective against LPS-induced liver injury in mice.

关键词： Scutellaria baicalensis Lipopolysaccharide Liver injury Cytokine Nuclear factor-κB

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Morphology of the ^(13)CO(3–2) millimetre emission across the gas disc surrounding the triple protostar GG Tau A using ALMA observations

引用

Research in Astronomy and Astrophysics 2018年第3期18卷 63-76页

作者： nguyen Thi Phuong Pham Ngoc Diep Anne Dutrey Edwige Chapillon Pierre Darriulat Stéphane Guilloteau Do Thi Hoai Pham Tuyet Nhung Ya-Wen Tang nguyen Thi Thao Pham tuan-Anh Department of Astrophysics Vietnam National Space CenterVietnam Academy of Science and Technology Graduate University of Science and Technology Vietnam Academy of Science and Technology Laboratoire d’Astrophysique de Bordeaux Université de Bordeaux IRAM F-38406 Saint Martin d’Hères Cedex Academia Sinica Institute of Astronomy and Astrophysics

Observations by the Atacama Large Millimetre/sub-millimetre Array of the dust continuum and ^13 CO（3–2） millimetre emissions of the triple stellar system GG Tau A are analysed,giving evidence for a rotating gas disc and a concentric and coplanar dust ring. The present work complements an earlier analysis（Tang et al.） by exploring detailed properties of the gas disc. A 95% confidence level upper limit of 0.24＂（34 au） is placed on the disc scale height at a distance of 1＂（140 au） from the central stars. Evidence for Keplerian rotation of the gas disc is presented,with the rotation velocity reaching-3.1 km s^-1 at 1＂ from the central stars,and a 99% confidence level upper limit of 9% is placed on relative contribution from a possible in-fall velocity. Variations of the intensity across the disc area are studied in detail and confirm the presence of a hot spot in the south-eastern quadrant. However several other significant intensity variations,in particular a depression in the northern direction,are also revealed. Variations of the intensity are found to be positively correlated to variations of the line width. Possible contributions to the measured line width are reviewed,suggesting an increase of the disc temperature and opacity with decreasing distance from the stars.

关键词： protoplanetary disks - stars low-mass - stars individual (GG Tau A)

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：