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Numerical investigation of the effect of seasonal variations of depthof-closure on shoreline evolution

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International Journal of Sediment Research 2021年第1期36卷 1-16页

作者： Xuan Tinh Nguyen minh Thanh tran Hitoshi Tanaka Trung Viet Nguyen Yuta Mitobe Cong Dien Duong Department of Civil Engineering Tohoku University

The current study presents the effects of seasonal variations in the depth-of-closure（D;） on shoreline evolution using a numerical,one-line shoreline *** erosion of the southern beach of the Nha trang Coast,which is located in south central of Vietnam,is selected as the study *** study area is immensely influenced by the tropical monsoon climate that has a clear pattern of large waves in the northeast monsoon season and calm waves in the non-monsoon *** analysis of the long-term measured shoreline variations from a video-camera system has found a strong correlation of these variations to the monsoon-dominated wave characteristics in the Nha trang ***,a new approach for determining the depth-of-closure with consideration of the seasonal wave climate changes is purposed in the current *** implementing this new approach into a numerical,one-line shoreline model,it is found that the seasonal variations of D;appear to better describe the periodical shoreline evolution due to the monsoon-dominated wave characteristics for the Nha trang *** important findings are considered to commonly apply for monsoon-dominated coastal regions in *** findings are useful information not only for scientific readers but also for the coastal authorities and managers in order to make better countermeasure plans against this kind of erosion mechanism in the future.

关键词： Video camera Shoreline change One-line theory Nha trang Beach Depth-of-closure Monsoon wave climate

Effects of lime treatment on the microstructure and hydraulic conductivity of Héricourt clay

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Journal of Rock Mechanics and Geotechnical Engineering 2014年第5期6卷 399-404页

作者： Thanh Danh tran Yu-Jun Cui Anh minh Tang Martine Audiguier Roger Cojean Mines ParisTech-Centre de Géosciences FontainebleauFrance Laboratoire Navier/CERMES Ecole des Ponts ParisTech6 et 8 Avenue Blaise Pascal77455 Marne-la-Vallée Cedex 2France Mines ParisTeche-Centre de Géosciences FontainebleauFrance

This study aims at evidencing the effects of lime treatment on the microstructure and hydraulic conductivityof a compacted expansive clay, with emphasis put on the effect of lime hydration and *** this purpose, evolutions of hydraulic conductivity were investigated for both lime-treatedand untreated soil specimens over 7 d after full saturation of the specimens and their microstructureswere observed at the end. Note that for the treated specimen, dry clay powder was mixed with quicklimeprior to compaction in order to study the effect of lime hydration. It is observed that lime hydration andmodification did not affect the intra-aggregate pores but increased the inter-aggregates pores size. Thisincrease gave rise to an increase of hydraulic conductivity. More precisely, the hydraulic conductivity oflime-treated specimen increased progressively during the first 3 d of modification phase and stabilisedduring the next 4 d which correspond to a short period prior to the stabilisation phase. The microstructureobservation showed that stabilisation reactions took place after 7 d. Under the effect of stabilisation,a decreasing hydraulic conductivity can be expected in longer time due to the formation ofcementitious compounds. 2014 Institute of Rock and Soil Mechanics, Chinese Academy of Sciences. Production and hosting byElsevier B.V. All rights reserved.

关键词： Clays Lime hydration Hydraulic conductivity Microstructure Temperature effect

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初中级越南汉语学习者状态补语习得偏误研究及建议 ——以胡志明市师范大学中文系为例

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初中级越南汉语学习者状态补语习得偏误研究及建议 ——以胡志明...

作者：陈氏清草（tran Thi Thanh Thao）河北大学

学位级别：硕士

补语是中文语法中的一个重要知识点,也是一个相对难的语法学习点,特别是对于越南学习者,因为在越南语中没有相似的结构,所以对于他们来说补语的难度更大。中文有着丰富而复杂的补语系统,其中,状态补语在汉语中使用频率高、结构复杂、语... 详细信息

补语是中文语法中的一个重要知识点,也是一个相对难的语法学习点,特别是对于越南学习者,因为在越南语中没有相似的结构,所以对于他们来说补语的难度更大。中文有着丰富而复杂的补语系统,其中,状态补语在汉语中使用频率高、结构复杂、语义繁多、语境因素强,被汉语教学界视为汉语教学的重点和难点。笔者是越南留学习者,也曾经经历过汉语学习初中级这段时间,因此特别理解初中级汉语学习者习得过程中的困难与学习过程中的需求。本文主要收集了越南胡志明市师范大学中文系初中级汉语学习者在使用汉语状态补语时产生的偏误,并进行了详细的偏误研究和分析。通过调查与分析,笔者旨在找出更科学有效的汉语状态补语教学方法。本文先对研究背景、研究目的和意义、研究方法等进行说明,对状态补语的语料搜集情况进行概述,本文选择《HSK标准教材2、3》中的状态补语为考察对象,以偏误分析理论、中介语理论和对比分析理论为指导,并采用调查分析、个别访谈等方法进行研究。其次对国际中文教学中的状态补语进行研究综述与相关界定,主要总结了状态补语的本体研究和国际中文教学中的状态补语研究,分析了状态补语研究现状。笔者还对初中级越南学习者的调查问卷和试题进行整理和分析,主要针对胡志明市师范大学中文系的初中级学习者,通过调查问卷与访谈进行状态补语偏误语料的搜集与统计。第四部分对初中级越南学习者学习状态补语的偏误进行了分类,共分为五类。随后,对初中级越南学习者学习汉语状态补语产生偏误的原因进行了分析,分为客观因素和主观因素,并探讨了学习者们回避状态补语学习的现象及其原因。最后是对状态补语的教学思考,针对引起偏误的原因提出具体的教学建议,并设计了部分教学计划,同时提供了《HSK标准教程1、2、3》中状态补语动词相关的参考例句和练习。希望本文研究成果能为越南初中级汉语语法教学提供启示,并能在实际教学中提高教学效果、降低学习难度、减轻教学压力,从而找到最佳的汉语状态补语教学途径。同时,也期望本研究能够为国际中文教学和研究贡献一份力量。

关键词：初中级越南学习者状态补语习得偏误

Treatment for COVID-19 patients in Vietnam: Analysis of time-to-recovery

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Asian Pacific Journal of Tropical Medicine 2020年第9期13卷 397-401页

作者： Khuong Quynh Long Hoang Hong Hanh tran Thi Tuyet Hanh La Ngoc Quang Hoang Van minh Hanoi University of Public Health 1A Duc Thang RoadDuc Thang WardNorth Tu Liem DistrictHanoiVietnam

Objective:To describe the recovery time and related factors among COVID-19 patients in ***:We used the secondary data obtained from the official database of the Ministry of Health of Vietnam and other public data sources that were available by April 9 th,*** proportional hazards model was carried out to identify factors related to recovery time among COVID-19 ***:By April 9 th,2020,the cumulative number of COVID-19 cases detected in Vietnam was 255,of which 129(50.6%)patients had fully *** median recovery time of patients was 17(95%CI=16-19)*** patients had a lower likelihood of recovery(HR=0.98,95%CI=0.97-0.99,P<0.001),whereas patients with a history of international incoming travel had a higher likelihood of recovery(HR=1.57,95%CI=1.03-2.40,P=0.036).There was no statistically significant difference in the recovery time of patients treated in different hospital ***:More attention is needed for older patients and who did not have international travel *** confirmed with COVID-19 could be treated at local health facilities to avoid unnecessary referrals and burdens to specialized hospitals at the central level.

关键词： COVID-19 Coronavirus Recovery Vietnam

Structural and luminescent properties of (Eu,Tb) PO_4·H_2O nanorods/nanowires prepared by microwave technique

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Journal of Rare Earths 2011年第12期29卷 1170-1173页

作者： Nguyen Thanh Huong Nguyen Duc Van Dinh Manh Tien Do Khanh Tung Nguyen Thanh Binh tran Kim Anh Le Quoc minh Institute of Materials Science Vietnam Academy of Science and Technology University of Engineering and Technology National University HanoiVietnam

Nanowires/nanorods of europium/terbium orthophosphate monohydrate with Eu^3＋ concentration of 6, 11, and 20 at.% were prepared by microwave synthesis method. The effects of Eu^3＋ doping concentration on structure, morphology and optical properties of nanomaterials were also investigated. The results showed that, for all studied Eu^3＋ doping concentrations, a single-crystalline phase of rhabdophane-type （Eu,Tb）PO4·H2O nanowires/nanorods was obtained by using microwave heating of an aqueous solution of terbium（Ⅲ） nitrate, europium（Ⅲ） nitrate and NH4H2PO4 with pH=2. The length and width of these nanowires/nanorods ranged from 150 to 300 nm and from 10 to 50 nm, respectively. The evidence of energy transfer from Tb^3＋ to Eu^3＋ due to the energy overlap between the donor Tb^3＋ and the acceptor Eu^3＋was observed obviously via a significant enhancement in the luminescent intensity of Eu^3＋. Keywords：

关键词： microwave technique nanowires/nanorods energy transfer fluorescence spectroscopy rare earths

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Evaluation of Weathering Performance of Rosin-Copper Based Treated Wood

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Journal of Renewable Materials 2022年第11期10卷 2765-2780页

作者： Thi Thanh Hien Nguyen Nho Quyet tran Thi minh Nguyet Nguyen Hien Mai Trinh Xuan Phuong Le Trong Kien Nguyen College of Wood Industry and Interior Design Vietnam National University of ForestryHa NoiViet Nam College of Economics and Management Northeast Forestry UniversityHarbinChina

This study aimed to evaluate the effect of natural weathering on some surface characteristics and mechanical properties of Styrax wood treated with mixtures of 1.0%,2.0%,or 4.0%rosin sizing agent and 3%copper *** samples after treatment were exposed to outdoor conditions for one year and changes in color,glossiness,weight loss,compression strength parallel to grain(CSPG),modulus of rupture(MOR),and modulus of elasticity(MOE)were investigated after 6 and 12-month of natural *** results showed that rosin-copper treatment could improve color stability and gloss of samples after *** losses of all rosin-copper treated samples after 12 months of exposure were negligible compared with the untreated control *** addition,rosin-copper treatment enhanced the CSPG compared to untreated controls,but slightly decreased the MOR and MOE of Styrax wood before *** weathering factors induced a reduction for all strength properties,however,the decrease rate for strength properties of rosin-copper treated samples was negligible compared with the untreated control samples after 12-month natural weathering *** FTIR and SEM-EDX confirmed that the use of the rosin-copper formulations to impregnate wood could decrease the hazard of the copper preservative leaching into the environment,while also enhancing more resistance against weathering factors and other biotic factors.

关键词： Rosin-copper weathering color stability CSPG MOR MOE

Prevalence and Patterns of Divorce in Vietnam： Tradition, Modernity, and Individualism

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Journal of Literature and Art Studies 2016年第3期6卷 298-316页

作者： tran Thi minh Thi Viet Nam Academy of Social Sciences Ha Noi Viet Nam

In Vietnam, divorce traditionally was considered scandalous for women, so there was a strong pressure against divorce, especially for women. While divorce has long been culturally discouraged and limited, divorce has been rapidly increasing after the renovation policy in late 1980s with alternative causes, consequences, etc Modernization is a process of transforming ＂traditional＂ society to ＂modern＂ one, in order to achieve economic development and growth, to innovate politics and to enhance their social structure towards a political, social, and economic system similar to those of western developed countries. In the field of marriage, family, and kinship, modernization process experiences the maintenance of traditional values and the appearance of the new modern values. This paper aims to examine trend and correlates of divorce and to identify social and cultural factors influencing the divorce decision, using data of divorce profiles of one district court in 10 years （i.e., 2000-2009） with total divorce profiles analyzed are 2,033 cases, of which 499 divorce couples in a rural district and 1,534 divorced couples in an urban area.

关键词： divorce incidence causes Vietnam tradition modernity modernization collectivism familialism individualism

Zirconium metal organic framework for design of tetragonal rare earth-doped zirconia nanoparticles

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Journal of Rare Earths 2019年第11期37卷 1230-1236页

作者： Lam Thi Kieu Giang Lukasz Marciniak Krzysztof Kamil Zur Dinh Manh Tien Nguyen Vu Nguyen Thanh Binh tran Kim Anh Le Quoc minh Institute of Materials Science Vietnam Academy of Science and Technology18 Hoang Quoc VietCau GiayHanoiViet Nam Graduate University of Science and Technology Vietnam Academy of Science and Technology18 Hoang Quoc VietCau GiayHanoiViet Nam Institute of Low Temperature and Structural Research Polish Academy of Sciencesul.Okolna 250-422 WroclawPoland Faculty of Mechanical Engineering Bialystok University of TechnologyWiejska 45C15-351 BialystokPoland Institute of Applied Physics and Scientific Instrument Vietnam Academy of Science and Technology18 Hoang Quoc VietCau GiayHanoiViet Nam Duy Tan University 03 Quang TrungDa NangViet Nam

Zirconium metal-organic frameworks ZrOBDC(where BDC=C6H4(COOH)2,terephthalic acid)doped and co-doped with rare earth ions Ln(ZrOBDC:Ln^3+,where Ln^3+=Eu3+and Tb^3+as well as Er^3+and Yb^3+)were used as precursors for the design of tetragonal rare earth doped zirconia nanoparticles(t-ZrO2:Ln^3+NPs)through annealing ***,characterization and luminescence properties of ZrOBDC:Ln^3+and ZrO2:Ln^3+NPs were *** as-obtained t-ZrO2:Ln^3+NPs have high purity with an average size of 20-30 *** luminescence spectra of ZrOBDC:Tb^3+and ZrOBDC:Eu3+display strong green and red emission at around 544 and 611 nm which correspond to 5D4→7F5 and 5D0→7F2 transitions of Tb^3+and Eu3+ions,*** green and red up-conversion emissions of ZrO2:Er^3+,Yb^3+NPs due to 2H11/2,4S3/2→4I15/2 and 4F9/2→4I15/2 transitions of the Er^3+ions are observed under 976 nm laser excitation.

关键词： Zirconium Rare earth ZrOBDC ZrOBDC:Ln3+ ZrO2:Ln3+ Up-conversion

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A flexible magnetoelectric field-effect transistor with magnetically responsive nanohybrid gate dielectric layer

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Nano Research 2015年第10期8卷 3421-3429页

作者： Nguyen minh Triet tran Quang Trung Nguyen Thi Dieu Hien Saqib Siddiqui Do-ll Kim Jai Chan Lee Nae-Eung Lee SchoolofAdvancedMaterialsScienceandEngineering SungkyunkwanUniversitySuwonKyunggi-do440-746RepublicofKorea SungkyunkwanUniversity(SKKU)AdvancedInstituteofNanotechnology(SAINT) 5ungkyunkwanUniversitySuwonKyunggi-do440-746RepublicofKorea SamsungAdvancedInstituteforHealthSciencesandTechnology(SAIHST) SungkyunkwanUniversitySuwonKyunggi-do440-746RepublicofKorea

Flexible magnetoelectric （ME） materials have been studied for new applications such as memory, energy harvesters, and magnetic field sensors. Herein, with the widely studied and progressive advantages of ME phenomena in the multiferroic field, we demonstrate a new approach for utilizing flexible ME materials as gate dielectric layers in ME organic field-effect transistors （ME-OFET） that can be used for sensing a magnetic field and extracting the ME properties of the gate dielectric itself. The magnetoelectric nanohybrid gate dielectric layer comprises sandwiched stacks of magnetostrictive CoFe2O4 nanoparticles and a highly piezoelectric poly（vinylidene fluoride-co-trifluoroethylene） layer. While varying the magnetic field applied to the ME gate dielectric, the ME effect in the functional gate dielectric modulates the channel conductance of the ME-OFET owing to a change in the effective gate field. The clear separation of the ME responses in the gate dielectric layer of ME-OFET from those of the other parameters was demonstrated using the AC gate biasing method and enabled the extraction of the ME coefficient of ME materials. Additionally, the device shows high stability after cyclic bending of 10,000 cycles at a banding radius of 1.2 cm. The device has significant potential for not only the extraction of the intrinsic characterization of ME materials but also the sensing of a magnetic field in integrated flexible electronic systems.

关键词： magnetoelectric magnetostriction CoFe2O4 nanoparticles P(VDF-TrFE) organic field-effecttransistor magnetic sensor