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Twin reversed arterial perfusion sequence-a rare and dangerous complication form of monochorionic twins:A case report

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World Journal of Clinical Cases 2022年第28期10卷 10214-10219页

作者： Nguyen Duy Anh Nguyen-thi Thu Ha Nguyen-thi Sim Nguyen Khac Toan phan-thi huyen thuong Nguyen Minh Duc Fetal Medicine Center Hanoi Obstetrics and Gynecology HospitalHanoi 100000Vietnam Department of Assisted Reproduction Hanoi Obstetrics and Gynecology HospitalHanoi 100000Vietnam Department of Obstetrics and Gynecology Hanoi University of Medicine and PharmacyHanoi 100000Vietnam Department of Radiology Pham Ngoc Thach University of MedicineHo Chi Minh City 700000Vietnam

BACKGROUND Twin reversed arterial perfusion(TRAP) sequence is an extremely rare congenital anomaly in monochorionic(MC) *** condition is characterized by a malformed fetus(acardiac twin) without cardiac activities being perfused by a structurally normal one(pump twin) via an artery-to-artery anastomosis in a reverse *** SUMMARY We described the first case of TRAP to receive laser surgery in *** 26-wk pregnancy was originally misdiagnosed in another hospital as MC twins with single intrauterine fetal *** admission to our center,the diagnosis was amended to a 26-wk TRAP sequence stage *** acardiac twin was 7.5 cm at the longest length,the ratio of the weight of the acardiac twin to the weight of the pump twin was more than 90%,the pump twin showed fetal distress with absent diastolic flow in umbilical artery of pump twin,and the peak systolic velocity in the middle cerebral artery = 1.6 Mo *** performed emergency laser photocoagulation of the acardiac twin’s umbilical *** surgery,we successfully maintained the pregnancy for 8 wk and ended it electively by cesarean section at 34 wk of gestation due to rupture of *** TRAP should be appropriately diagnosed and treated early to avoid complications of the pump *** laser photocoagulation is a new and effective treatment for this condition.

关键词： Twin reversed arterial perfusion Acardiac twin Pump twin Laser Case report

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Highly active brookite TiO2-assisted photocatalytic degradation of dyes under the simulated solar-UVA radiation

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Progress in Natural Science:Materials International 2019年第6期29卷 641-647页

作者： huyen Tran thi thuong Chi Tran thi Kim Liem Nguyen Quang Hendrik Kosslick Institute of Materials Science (IMS) Vietnam Academy of Science and Technology (VAST) University of Rostock Institute of Chemistry Department of Inorganic Chemistry

Brookite TiO2nanoparticles were synthesized by hydrothermal method and characterized by X-ray powder diffraction(XRD), diffuse reflectance UV–Visible spectroscopy(DRUV), and scanning electron microscopy(SEM). The obtained particles were spherical in shape with the diameter of about ～10 nm under the hydrothermal temperature of 175 °C. The photocatalytic performance of brookite was investigated in the photodegradation of dyes(rhodamine B and rose bengal) under UV-A radiation by low-power lamp. The activity of brookite and the photodegradation efficiency of dyes were estimated using a UV–Visible spectrophotometer and a total organic carbon(TOC) analyzer. Compared to anatase and rutile prepared by the similar synthesis procedure, brookite is highly active in terms of decolourization, aromatic ring opening, and mineralization.

关键词： Brookite Anatase Dye Photocatalytic degradation Decolourization Mineralization

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

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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

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越南学生汉语社会称谓语偏误研究 ——以越南人民警察学院为例

越南学生汉语社会称谓语偏误研究 ——...

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作者： phan thi NHAN huyen（潘小娴）华中师范大学

学位级别：硕士

汉、越两语的社会称谓系统“同大于异”,可汉语社会称谓语系统仍然是越南学生学习汉语的难点之一。越南是“一带一路”的重要节点,该国学习汉语的人数逐年增高,但目前对外汉语教学领域中称谓语的研究鲜有以越南学生为研究对象的。在此... 详细信息

汉、越两语的社会称谓系统“同大于异”,可汉语社会称谓语系统仍然是越南学生学习汉语的难点之一。越南是“一带一路”的重要节点,该国学习汉语的人数逐年增高,但目前对外汉语教学领域中称谓语的研究鲜有以越南学生为研究对象的。在此基础上,本文以越南人民警察学院的汉语学生为研究对象,研究他们在学习汉语社会称谓语生的困难与障碍。之所以选择越南人民警察学院,是因为笔者是该校的专职汉语教师,非常了解该大学的汉语教学情况。此外,作为培养越南警官的最高学府,该校非常注重外语教学工作,汉语是该校学生的必修课,汉语社会称谓语对这些未来的越南警官有着特殊的意义。本文依托越南人民警察学院使用的三部汉语教材,即《汉语教材》、《博雅汉语》和《警务汉语》,整理搜集到215个汉语社会称谓语,从中选取了 34个校园内常见的社会称谓语,以此为切入点来了解越南学生学习汉语社会称谓语情况,全面分析了学习过程中所产生的偏误及成因。越南学生在学习汉语社会称谓语时容易出现混淆替换、过度泛化、语素误译、语素添加、语素缺失、颠倒结构等六类偏误。比如,越南学生会说“*服务,我要点菜”等。其中,混淆替换和颠倒结构类偏误数量较多。造成这些偏误的原因比较多样,其中,汉语社会称谓语系统的庞杂性造成的干扰以及越南语的定中结构,汉译越称谓的重复等负迁移影响最大。本文还发现越南学习者对新兴的汉语社会称谓还缺乏了解,存在自我妨碍心理,容易回避。我们根据这些偏误类型以及越南学生的特点,提出了自己的建议,比如在汉语社会教学中强调理实一体,采取的教学法时注重对比分析法、情景教学法。期待为越南的教学者提供教学建议,帮助越南学生提升汉语能力,实实在在地助力“一带一路”计划中的“民心相通”。

关键词：汉语社会称谓语越南学生偏误

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Growth of single crystals in the (Na_(1/2)Bi_(1/2))TiO_(3)-(Sr_(1-x)Ca_(x))TiO_(3) system by solid state crystal growth

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Journal of Advanced Ceramics 2021年第5期10卷 973-990页

作者： phan Gia LE huyen Tran TRAN Jong-Sook LEE John G.FISHER Hwang-Pill KIM Wook JO Won-Jin MOONC School of Materials Science and Engineering Chonnam National University77 Yongbong-roBuk-guGwangju 61186Republic of Korea School of Materials Science and Engineering Ulsan National Institute of Science and Technology50 UNIST-gilEonyang-eupUlju-gunUlsan 44919Republic of Korea Korea Basic Science Institute Gwangju Center77 Yongbong-roBuk-guGwangju 61186Republic of Korea

Ceramics based on(Na_(1/2)B_(1/2))TiO_(3) are promising candidates for actuator applications because of large strains generated by an electric field-induced phase *** example,the(1-x)(Na_(1/2)Bi_(1/2))TiO_(3)-xSrTiO_(3) system exhibits a morphotropic phase boundary at x=0.2-0.3,leading to high values of inverse piezoelectric constant d_(33),which can be further improved by the use of single *** our previous work,single crystals of (Na_(1/2)B_(1/2))TiO_(3)-SrTiO_(3) and (Na_(1/2)Bi_(1/2))TiO_(3)-TiO_(3) were grown by the solid state crystal growth *** in the(Nai/2Bi/2)TiO3-SrTiO3 system was sluggish whereas the (Na_(1/2)B_(1/2))TiO_(3)-CaTiO_(3) single crystals grew *** the present work,0.8(Na_(1/2)Bi_(1/2))Ti0_(3)-0.2(Sr_(1-x)Ca_(x))Ti0_(3) single crystals(with x=0.0,0.1,0.2,0.3,0.4)were produced by the solid state crystal growth technique in an attempt to improve crystal growth *** dependence of mean matrix grain size,single crystal growth distance,and electrical properties on the Ca concentration was investigated in *** investigations indicated that at x=0.3 the matrix grain growth was suppressed and the driving force for single crystal growth was *** Sr with Ca increased the shoulder temperature T_(s) and temperature of maximum relative permittivity T_(max),causing a decrease in inverse piezoelectric properties and a change from normal to incipient ferroelectric behavior.

关键词： (Na_(1/2)Bi_(1/2))TiO_(3) lead-free piezoelectric single crystal microstructure electrical properties

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Surface Mapping of Resistive Switching CrO_x thin Films

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Advances in Materials Physics and Chemistry 2016年第3期6卷 21-27页

作者： Kim Ngoc Pham Kieu Hanh thi Ta Lien thuong thi Nguyen Vinh Cao Tran Bach Thang phan Faculty of Materials Science University of Science Vietnam National University Ho Chi Minh City Vietnam Faculty of Resources and Environment Thu Dau Mot University Binh Duong City Vietnam Laboratory of Advanced Materials University of Science Vietnam National University Ho Chi Minh City Vietnam

In this work, we investigated resistive switching behavior of CrOx thin films grown by using sputtering technique. Conventional I-V measurements obtained from Ag/CrOx/Pt/Ti/SiO2/Si structures depict the bipolar switching behavior, which is controlled by formation/dissolution processes of Ag conducting filaments through electrochemical redox reaction under external electric field driven. Conductive atomic force microscopy (C-AFM) technique provides the valuable mapping images of existing Ag filaments at low resistance state as well as the characteristics of filament distributions and diameters. this study also reveals that where the higher amplitude of topography is, the easier possibility of forming conducting filament paths is on CrOx surface films.

关键词： Resistive Switching Chromium Oxide C-AFM Surface Mapping Metal Filament

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新冠疫情背景下越南北部高校线上汉语教学现状调查研究

新冠疫情背景下越南北部高校线上汉语教学现状调查研究

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作者：赖氏玄商（LAI thi huyen thuong）华中师范大学

学位级别：硕士

2020年初春爆发的新冠疫情对人类生活各方面产生了极大的影响,汉语教学也不例外。同年4月越南政府实施社会隔离,为了停课不停学各校采取了将传统课堂转移到了线上。实施过程中,线上汉语教学虽然还存在许多问题,需要不断研究与改进,但其... 详细信息

2020年初春爆发的新冠疫情对人类生活各方面产生了极大的影响,汉语教学也不例外。同年4月越南政府实施社会隔离,为了停课不停学各校采取了将传统课堂转移到了线上。实施过程中,线上汉语教学虽然还存在许多问题,需要不断研究与改进,但其也显示出拥有巨大的发展潜力。笔者作为一名越南留学生,一方面对越南汉语教学有一定的了解,并容易拿到越南汉语教学的第一手数据和资料,另一方面通过一年在线读研究生时间让我深深地体会到中国高质量的在线学习环境,这使我意识到越南线上汉语教学还有很大的发展空间。因此笔者以越南北部高校线上汉语教学为切入点,深入探究其的优势和存在的问题,从而提出具有针对性的解决方案,希望能为未来越南线上汉语教学提供参考与借鉴。本文共分五个部分:第一部分:阐述笔者选题的原由、研究意义、研究内容和研究方法,对前者的相关研究进行综述,并对问卷调查进行说明。第二部分:笔者概括了越南北部高校汉语教学的类型及规模,并通过问卷调查了解疫情前越南北部高校线下汉语教学整体现状。我们主要针对课程设置与教材使用、网络平台使用情况、教学方式、课堂互动以及教师和学生对自身教与学各环节评价等方面进行研究。第三部分:针对疫情背景下越南北部高校线上汉语教学的平台使用、教学方式、课堂互动及师生对自身线上教学各环节评价进行调查分析。第四部分:将越南北部高校疫情前线下汉语教学与疫情背景下线上汉语教学进行对比分析。对比内容包括学生网络平台使用情况、教学方式、课堂互动及教学评价四方面。第五部分:从对比分析结果指出线上汉语教学的优点和存在的问题,从而提出具有针对性的解决对策。调查结果表明到目前为止越南北部高校线上汉语教学还存在许多问题,如缺乏针对教学设计的线上教学平台,教学资源缺乏针对性和同步性,线上教学互动情况、课堂管理及测评效果差于传统线下教学等问题。但是,其还显示出具有许多优势,如具有便捷性,为学生提供更方便的学习方式及更丰富的学习资源,并且提高学生的自主学习能力。因此,如何克服所存在的问题,最大限度发挥线上汉语教学的优势对越南汉语教学显得十分重要。

关键词：越南北部高校汉语教学线上教学线下教学

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Enrichment of hydrogen in product gas from a pilot-scale rice husk updraft gasification system

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Carbon Resources Conversion 2022年第3期5卷 231-239页

作者： phan Dinh Tuan Le Minh Quan Vo Trang Nhi Hoang Minh Huong Le thi Kim Phung Daolun Feng Hochiminh City University of Natural Resources and Environment 236B Le Van Sy St.Tan Binh Dist.Ho Chi Minh City 70.000Viet Nam Applied Research Institute for Natural Resources Materialand Environment58/4 Tran Van Du St.Tan Binh Dist.Ho Chi Minh City 70.000Viet Nam Hochiminh City University of Technology 268 Ly Thuong Kiet St.Dist.10Ho Chi Minh City 70.000Viet Nam Vietnam National University-Ho Chi Minh(VNU-HCM) Linh Trung WardThu Duc CityHo Chi Minh CityViet Nam College of Marine Science and Engineering Shanghai Maritime UniversityShanghai 200135PR China

An updraft gasifier was employed to treat 3 kg of dried rice husk per batch with different types of gasifying agents such as air,steam/air,and air with dolomite catalyst addition at various operating *** H2 content,low heating value,and H2/CO ratio in syngas were compared to determine the most effective solution to enhance the H2 production from rice husk *** presence of dolomite in air gasification produced the highest H2 content in the product gas,up to 15.4 mol%,followed by 7.08 and 3.6 mol%when steam/air and air standalone were used as gasifying agents,*** higher low heating value of syngas 5.1 MJ/Nm3 was observed in catalytic air gasification compared to 3.6 MJ/Nm3 when steam was *** optimal operation condition was reported at an airflow rate of 3 m3/h and a catalyst mixing ratio of 15%.

关键词： Rice husk Enriched hydrogen syngas Dolomite Updraft gasifier

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越南税收行政改革

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广西财经学院学报 2008年第3期21卷 27-29页

作者：阮氏商玄越南财政学院海关税收系

该文分析了越南税收行政改革取得的突破性进展,提出了新时期税收行政改革的基本方向和措施。

关键词：越南税收行政改革

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Suzuki Reaction of Aryl Bromides Using a Phosphine-Free Magnetic Nanoparticle-Supported Palladium Catalyst

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催化学报 2011年第11期32卷 1667-1676页

作者： Nghia T. BUI Trung B. DANG Ha V. LE Nam T. S. phan Department of Chemical Engineering HCMC University of Technology VNU-HCM 268 Ly Thuong Kiet Distriet 10 Ho Chi Minh City Viet Nam

A palladium catalyst immobilized on superparaganetic nanoparticles was prepared with a palladium loading of 0.30 mmol/g. The catalyst was characterized using X-ray diffraction, scanning electron microscopy, transmission electron microscopy, vibrating sample magnetometry, thermogravimetric analysis, Fourier transform infrared, atomic absorption spectrophotometry, and nitrogen adsorption. The immobilized palladium catalyst was an efficient catalyst without added phosphine ligands for the Suzuki cross-coupling reaction of several aryl bromides with phenylboronic acid. The recovery of catalyst was simply by magnetic decantation in the presence of a magnet. The immobilized palladium catalyst can be reused many times without significant degradation in catalytic activity. No leaching of active palladium species into the reaction solution was detected.

关键词： superparamagnetic nanoparticle Suzuki reaction palladium aryl bromide

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