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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

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

数字经济驱动下创新生态系统空间演化与迭代机制研究

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科技创业月刊 2024年第7期37卷 34-42页

作者：徐雪娇阮氏如龚众北华大学经济管理学院吉林省吉林市132013

数字经济的发展不仅改变了创新生态系统的理论基础和行为逻辑,也改变了创新生态系统的结构和特征,促使创新生态系统空间演化模式和迭代机制发生转变。基于数字经济理论和创新生态系统理论,探索了数字经济驱动下创新生态系统空间演化与... 详细信息

数字经济的发展不仅改变了创新生态系统的理论基础和行为逻辑,也改变了创新生态系统的结构和特征,促使创新生态系统空间演化模式和迭代机制发生转变。基于数字经济理论和创新生态系统理论,探索了数字经济驱动下创新生态系统空间演化与迭代机制,并构建理论模型,得出以下结论:第一,在数字经济的驱动下,创新生态系统的创新要素高匹配性、创新网络优化性、创新边界延展性、创新平台打造便捷性特征更加明显;第二,数字经济驱动下创新生态系统呈现放射状、凝聚状、网络状、点状的空间演化模式;第三,数字经济驱动下创新生态系统的迭代呈现出螺旋上升型、思维驱动型、技术引领型、周期扩张型4种机制。

关键词：数字经济创新生态系统空间演化迭代机制

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Effects of Processing Parameters on Mechanical Properties and Structure of Banana Fiber-Reinforced Composites

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Journal of Renewable Materials 2018年第6期6卷 662-670页

作者： Dan-Thuy Van-Pham Minh Tri Nguyen Chanh-Nghiem Nguyen thi Truc Duyen Le thi Yen nhu Pham Khai thinh Nguyen Yukihiro Nishikawa Qui tran-Cong-Miyata Department of Chemical Engineering Can Tho UniversityCan Tho CityViet Nam Department of Automation Technology Can Tho UniversityCan Tho CityViet Nam Department of Macromolecular Science and Engineering Graduate School of Science and TechnologyKyoto Institute of TechnologyMatsugasakiSakyo-kuKyoto 606-8585Japan

The mechanical properties of unidirectional natural fiber-reinforced composites are generally affected by several processing parameters during compression *** study investigates the effects of processing temperature,time,and pressure on the tensile and flexural properties of acrylonitrile butadiene styrene reinforced by banana fibers.X-ray CT imaging was employed to find the relationship between the mechanical properties and structure of the processed ***,the water absorption of composites was observed and the way in which the mechanical properties evolved after water absorption was *** tensile and flexural properties of the unidirectional banana fiber-reinforced composite were found to be inversely proportional to the *** addition,high-pressure compression molding might result in cracks and floating fibers that would significantly reduce its mechanical *** composite with the highest strength,smallest porosity and lowest water absorption was optimally prepared at T=170℃,t=20 min,and P=100 kg cm^-2.

关键词： Banana fiber composite compression molding porosity X-ray CT

Enhancement of water absorption capacity and compressibility of hydrogel sponges prepared from gelatin/chitosan matrix with different polyols

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Progress in Natural Science:Materials International 2022年第1期32卷 54-62页

作者： thi Sinh Vo tran thi Bich Chau Vo Trung Tien tran Nhan Duy Pham School of Mechanical Engineering Sungkyunkwan University Department of Industrial Management Can Tho University Department of Chemistry Memorial University of Newfoundland

The hydrogel sponges have prepared successfully from gelatin/chitosan(GEL/CTS) matrix with different polyols basing on scanning electron microscopy(SEM) and Fourier-transform infrared spectroscopy(FTIR) analysis. The results indicate that the compressibility and thermal properties(thermal gravimetric analysis, TGA) were improved significantly with adding the different polyols [poly(vinyl alcohol)-PVA, and poly(ethylene glycol)-poly(propylene glycol)-poly(ethylene glycol) – PEPEG] into GEL/CTS matrix. Specially, the as-prepared hydrogel sponges with superabsorbent behavior were also investigated with the attained water absorption capacity to 605 g gand 585 g gfor GCV＿1/1/0.3 and GCE＿1/1/0.3 sponges, respectively, as well as the excellent water absorption capacity in a wide range of p H and salt concentration. Hence, these studies demonstrated that the hydrogel sponges are concerned as potential and promising candidates to apply especially in the fields of biomedicine and hygiene.

关键词： Hydrogel sponges Absorbent Chitosan Polyols Gelatin Water absorption capacity

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“神”速高铁——感受中国时代脉动

孔子学院（中西文对照版） 2024年第1期 52-55页

作者：陈氏深孟烨(翻译) 不详

2019年,我还是越南河内大学中文系的大三学生,因热爱中国文化选择了中文专业,也因此格外关注中国的发展变化。高铁,被评为中国的“新四大发明”之一,也是最能体现中国制造、中国智慧的时代符号之一。中国有句古话,“百闻不如一见”,幸... 详细信息

2019年,我还是越南河内大学中文系的大三学生,因热爱中国文化选择了中文专业,也因此格外关注中国的发展变化。高铁,被评为中国的“新四大发明”之一,也是最能体现中国制造、中国智慧的时代符号之一。中国有句古话,“百闻不如一见”,幸运如我,在那年被学校选中,参加了中国大连外国语大学主办的夏令营活动,有机会亲身领略高铁的风采。

关键词：中文专业夏令营活动越南河内四大发明高铁大学中文系大连外国语大学大三学生

Object Detection in Remote Sensing Images Using Picture Fuzzy Clustering and MapReduce

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Computer Systems Science & Engineering 2022年第12期43卷 1241-1253页

作者： tran Manh Tuan tran thi Ngan Nguyen Tu Trung Faculty of Computer Science and Engineering Thuyloi University175 Tay SonDong DaHanoi010000Vietnam

In image processing, one of the most important steps is image segmentation. The objects in remote sensing images often have to be detected in order toperform next steps in image processing. Remote sensing images usually havelarge size and various spatial resolutions. Thus, detecting objects in remote sensing images is very complicated. In this paper, we develop a model to detectobjects in remote sensing images based on the combination of picture fuzzy clustering and MapReduce method (denoted as MPFC). Firstly, picture fuzzy clustering is applied to segment the input images. Then, MapReduce is used to reducethe runtime with the guarantee of quality. To convert data for MapReduce processing, two new procedures are introduced, including Map_PFC and Reduce_*** formal representation and details of two these procedures are presented in thispaper. The experiments on satellite image and remote sensing image datasets aregiven to evaluate proposed model. Validity indices and time consuming are usedto compare proposed model to picture fuzzy clustering model. The values ofvalidity indices show that picture fuzzy clustering integrated to MapReduce getsbetter quality of segmentation than using picture fuzzy clustering only. Moreover,on two selected image datasets, the run time of MPFC model is much less thanthat of picture fuzzy clustering.

关键词： Remote sensing images picture fuzzy clustering image segmentation object detection MapReduce

An isogeometric approach to free vibration analysis of bi-directional functionally graded porous doubly-curved shallow microshells with variable length-scale parameters

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Frontiers of Structural and Civil Engineering 2023年第12期17卷 1871-1894页

作者： Khuat Duc DUONG Dao nhu MAI Phung Van MINH tran Van KE Faculty of Mechanical Engineering Hanoi University of IndustryHanoi 100000Vietnam Institute of Mechanics Vietnam Academy of Science and TechnologyHanoi 100000Vietnam Faculty of Mechanical Engineering Le Quy Don Technical UniversityHanoi 100000Vietnam

this study uses iso-geometric investigation,which is based on the non-uniform rational B-splines(NURBS)basis function,to investigate natural oscillation of bi-directional functionally graded porous(BFGP)doublycurved shallow microshells placed on Pasternak foundations with any boundary *** characteristics of the present material vary in both thickness and axial directions along the *** be more specific,a material length-scale coefficient of the microshell varies in both thickness and length directions as the material's mechanical *** is able to develop a differential equation system with varying coefficients that regulate the motion of BFGP double-curved shallow microshells by using Hamilton principle,Kirchhoff-Love hypothesis,and modified couple stress *** numerical findings are reported for thin microshells that are spherical,cylindrical,and hyperbolic paraboloidal,with a variety of planforms,including rectangles and *** validity and effectiveness of the established model are shown by comparing the numerical results given by the proposed formulations with previously published findings in many specific *** addition,influences of length scale parameters,power-law indexes,thickness-to-side ratio,and radius ratio on natural oscillation responses of BFGP microshells are investigated in detail.

关键词： Kirchhoff-Love's shell theory isogeometric analysis bi-directional functionally graded free vibration variable length-scale parameter

Development of a PARCS/Serpent model for neutronics analysis of the Dalat nuclear research reactor

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Nuclear Science and Techniques 2021年第2期32卷 32-44页

作者： Viet-Phu tran Kien-Cuong Nguyen Donny Hartanto hoai-Nam tran Vinh Thanh tran Van-Khanh hoang Pham nhu Viet Ha Institute for Nuclear Science and Technology(INST) Vietnam Atomic Energy Institute(VINATOM)179 Hoang Quoc Viet str.Cau Giay DistrictHanoi 100000Vietnam Nuclear Research Institute(NRI) Vietnam Atomic Energy Institute(VINATOM)01 Nguyen Tu LucDalatLamdong 670000Vietnam Department of Mechanical and Nuclear Engineering University of SharjahPO.BOX 27272SharjahUnited Arab Emirates Institute of Fundamental and Applied Sciences Duy Tan UniversityHo Chi Minh city 700000Vietnam Faculty of Natural Science Duy Tan UniversityDanang 550000Vietnam Nuclear Safety Division Technical Support Center for Radiation and Nuclear Safety and Emergency ResponseVietnam Agency for Radiation and Nuclear Safety(VARANS)113 Tran Duy Hung str.Cau Giay DistrictHanoi 100000Vietnam

Cross-sectional homogenization for full-core calculations of small and complex reactor configurations,such as research reactors,has been recently recognized as an interesting and challenging *** paper presents the development of a PARCS/Serpent model for the neutronics analysis of a research reactor type TRIGA Mark-II loaded with Russian VVR-M2 fuel(known as the Dalat Nuclear Research Reactor or DNRR).The full-scale DNRR model and a supercell model for a shim/safety rod and its surrounding fuel bundles with the Monte Carlo code Serpent 2 were proposed to generate homogenized fewgroup cross sections for full-core diffusion calculations with *** full-scale DNRR model with Serpent 2 was also utilized as a reference to verify the PARCS/Serpent *** of the effective neutron multiplication factors,radial and axial core power distributions,and control rod worths showed a generally good agreement between PARCS and Serpent *** addition,the discrepancies between the PARCS and Serpent 2 results are also ***,the results indicate the applicability of the PARCS/Serpent model for further steady state and transient analyses of the DNRR.

关键词： PARCS Serpent 2 Group constant DNRR