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Journal of Materials Science & Technology 2015年第5期31卷 479-483页

作者： nguyen Van Chuc Cao thi thanh nguyen Van Tu Vuong T.Q Phuong Pham Viet Thang Ngo thi thanh Tam Institute of Materials Science Vietnam Academy of Science and Technology Hanoi University of Science Vietnam National University

In this study,graphene-carbon nanotube（CNT） hybrid films were directly synthesized on polycrystalline copper（Cu） substrates by thermal chemical vapor deposition（CVD） *** films were synthesized on Cu substrate at 1000 ℃ in mixture of gases:argon（Ar）,hydrogen（H2）,and methane（CH4）.Then,carbon nanotubes（CNTs） were grown uniformly on the surface of graphene/Cu films at 750 ℃ in mixture of Ar,*** acetylene（C2H2） *** salt FeCl3solution deposited onto the surface of graphene/Cu substrate by spin coating method was used as precursor for the growth of the *** density and quality of the CNTs on the surface of graphene/Cu films can be controlled by varying the concentration of FeCl3salt catalyst.

关键词： Graphene Carbon nanotube(CNT) Hybrid films Copper

One-step hydrothermal synthesis of Sn-doped α-Fe_(2)O_(3) nanoparticles for enhanced photocatalytic degradation of Congo red

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Journal of Semiconductors 2022年第12期43卷 22-31页

作者： Van Nang Lam thi Bich Vu Quang Dat Do thi thanh Xuan Le Tien Dai nguyen T-thanh-Bao nguyen Hoang Tung Do thi Tu Oanh nguyen Department of Natural Sciences Hoa Lu UniversityNinh NhatNinh Binh CityViet Nam Institute of Theoretical and Applied Research Duy Tan UniversityHanoi 100000Viet Nam Faculty of Natural Sciences Duy Tan UniversityDa Nang 550000Vietnam Institute of Physics Vietnam Academy of Science and Technology10 Dao TanBa DinhHanoiVietnam Institute of Materials Science Vietnam Academy of Science and Technology18 Hoang Quoc VietCaugiayHanoiVietnam

We report on the synthesis of Sn-doped hematite nanoparticles(Sn-α-Fe_(2)O_(3) NPs)by the hydrothermal *** prepared Sn-α-Fe_(2)O_(3) NPs had a highly pure and well crystalline rhombohedral phase with an average particle size of 41.4 *** optical properties of as-synthesizedα-Fe_(2)O_(3) NPs show a higher bandgap energy(2.40-2.57 eV)than that of pure bulkα-Fe_(2)O_(3)(2.1 eV).By doping Sn intoα-Fe_(2)O_(3) NPs,the Sn-doped hematite was observed a redshift toward a long wavelength with in-creasing Sn concentration from 0%to 4.0%.The photocatalytic activity of Sn-dopedα-Fe_(2)O_(3) NPs was evaluated by Congo red(CR)dye *** degradation efficiency of CR dye using Sn-α-Fe_(2)O_(3) NPs catalyst is higher than that of pureα-Fe_(2)O_(3) *** highest degradation efficiency of CR dye was 97.8%using 2.5%Sn-dopedα-Fe_(2)O_(3) NPs catalyst under visible-light *** results suggest that the synthesized Sn-dopedα-Fe_(2)O_(3) nanoparticles might be a suitable approach to develop a photocatalytic degradation of toxic inorganic dye in wastewater.

关键词： α-Fe_(2)O_(3)nanoparticles Sn Congo red photocatalytic properties photodegradation

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

Hepatitis B vaccination status and associated factors among health science students

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Asian Pacific Journal of Tropical Medicine 2023年第5期16卷 213-219页

作者： binh thanh nguyen Lan Y Vo Tap Van nguyen Minh Cong Vo Tinh Dang Pham Han thi Ngoc nguyen Lynda Boyer-Chu Giao Huynh Faculty of Medicine Tra Vinh UniversityTra Vinh CityTra Vinh ProvinceVietnam Faculty of Public Health University of Medicine and Pharmacy at Ho Chi Minh CityHo Chi Minh CityVietnam Faculty of Medical Management Nguyen Tat Thanh UniversityHo Chi Minh CityVietnam Department of Ear Nose Throat-Head and Neck Surgery FV hospitalHo Chi Minh CityVietnam Department of Anaesthesia and Intensive Care FV hospitalHo Chi Minh CityVietnam Infection Control Department University Medical Center Ho Chi Minh CityHo Chi Minh CityVietnam San Francisco Unified School District San FranciscoCaliforniaUSA

Objective:To evaluate hepatitis B virus(HBV)vaccine coverage and its associated factors among health science students in ***:this cross-sectional study involving 459 health science students at Tra Vinh University was conducted between April and June *** were collected using a structured questionnaire with items on sociodemographic characteristics,knowledge and attitude about HBV,and vaccination status.A multivariable logistic regression model was used to explore the factors associated with vaccination ***:The majority of participants were female(65.8%)and enrolled at the medical school(56.2%).A total of 30.3%participants received the full dose of the HBV *** percentages of participants with sufficient knowledge and positive attitudes toward HBV infection were 75.2%and 43.4%,*** was 11.8 times higher in sixth-year medical students than any healthcare student in their first-year[adjusted odds ratio(aOR)11.8,95%CI 3.1-45.1,P<0.001],and the coverage was also significant higher in those who had sufficient knowledge(aOR 2.0,95%CI 1.1-3.9,P<0.05)and positive attitudes(aOR 3.0,95%CI 1.9-4.8,P<0.05)than in their ***:The majority of students were not fully vaccinated against HBV,indicating they were vulnerable to the *** and authorities should reinforce health education messages aimed at encouraging all students to get vaccinated with the HBV vaccine,enhance their awareness and knowledge of HBV,and improve attitudes toward HBV infection prevention.

关键词： Hepatitis B Knowledge Attitude Practice Vaccination Students

Designing Software to Analyze Sewing Process of Industrial Knitted Products

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Computer Systems Science & Engineering 2023年第2期44卷 1837-1852页

作者： Phan thanh Thao nguyen thanh Hung Pham thi Le My nguyen Xuan Hiep Duy-Nam Phan Hanoi University of Science and Technology Hanoi10000Vietnam

In the textile industry,garment manufacturing contains four major pro-cesses containing cutting,sewing,ﬁnishing,and *** is the most crucial and intricate section,dealing with a large number of varied operations.A successful sewing process needs to be optimized regarding different factors,including time,sewing equipment,and skilled *** lineﬂow is combined by a set of operations with a particular *** utmost impor-tance of all garment industry is to arrange the workstations to minimize the num-ber of employees in order to produce at the best productive rate with the most reasonable cost,shortest time,and satisfying *** most garment factories,the production lines are balanced using the empirical judgment of the line *** the whole process the data of production time at each step,labor pro-ductivity,proper choices of equipment were always needed to calculate line efﬁ*** far as the issue is concerned,there has not been an academically sewing process analyzing software providing adequate data of sewing motions and sewing time as the credible input for the line balancing *** this goal,this paper presents the results of research on optimizing academically self-built software to analyze the sewing process of knitted products applied to industrial production using Java programming language on Google *** results achieved by the software are not only to analyze sewing products and the technological sewing process,calculate the sewing time on the machine but also analyze the sewing activities of workers into manipulations,movements,and motions to calculate the preparation time for two typical knitted products,namely,Polo-Shirt and T-Shirt with the case studies at General Textile Garment Joint Stock Company Hanoi and Star Fashion Company Limited.

关键词： Sewing motion sewing time GSD MTM polo-shirt T-shirt sewing process sewing operation analyzing software

Some Mean Convergence Theorems for the Maximum of Normed Double Sums of Banach Space Valued Random Elements

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Acta Mathematica Sinica,English Series 2024年第7期40卷 1727-1740页

作者： Andrew ROSALSKY Le Van thanh nguyen thi THUY Department of Statistics University of FloridaGainesvilleFL 32611-8545USA Department of Mathematics Vinh UniversityVinhNghe AnViet Nam High School for Gifted Students Vinh UniversityVinhNghe AnViet Nam

In this correspondence,we establish mean convergence theorems for the maximum of normed double sums of Banach space valued random *** of the results pertain to random elements which are *** expand and improve a number of particular cases in the literature on mean convergence of random elements in Banach *** of the main contributions of the paper is to simplify and improve a recent result of Li,Presnell,and Rosalsky[Journal of Mathematical Inequalities,16,117–126(2022)].A new maximal inequality for double sums of M-dependent random elements is proved which may be of independent *** sharpness of the results is illustrated by four examples.

关键词： Double sum mean convergence Rademacher type p Banach space Banach space valued random element M-dependent random elements

Fuzzy MCDM for Improving the Performance of Agricultural Supply Chain

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Computers, Materials & Continua 2022年第11期73卷 4003-4015页

作者： Le thi Diem My Chia-Nan Wang nguyen Van thanh Department of Industrial Engineering and Management National Kaohsiung University of Science and TechnologyKaohsiung CityTaiwan Faculty of Commerce Van Lang UniversityHo Chi Minh CityVietnam

Fertilizer industry in Vietnam and globally have entered the saturation *** the growth rate slowing down,this poses challenges for the development impetus of the fertilizer industry in the next *** fact,over the past few decades,Vietnam’s crop industry has abused excessive investment in chemical fertilizers,with organic fertilizers are rarely used or not at all,limiting crop productivity,increasing pests and *** develop sustainable agriculture,Vietnam’s crop industry must limit the use of chemical fertilizers,increase the use of environmentally friendly organic and natural mineral fertilizers to produce clean agricultural products which is ***,it is necessary to consider and choose the right supplier to ensure the goal of sustainable *** Fuzzy Analytic Hierarchy Process(SF-AHP),and the combinative distance-based assessment(CODAS)are new Multicriteria Decision Making(MCDM)method which can be used to solve supplier selection *** paper uses an effective solution based on a combined the concept of triple bottom line(TBL),SF-AHP and CODAS approach to help agriculture companies that need to select the best fertilizer *** research can support supply chain managers to achieve supply chain systems that reduce not only sourcing costs,but also develop sustainable agriculture.

关键词： Fuzzy theory MCDM model fertilizer agricultural supply chain optimization

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

Optimization Agricultural Supply Chain:A Case Study of Fertilizer Supplier Selection

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Computers, Materials & Continua 2022年第8期72卷 4057-4068页

作者： nguyen Van thanh nguyen thi Kim Lan Syed Tam Husain nguyen Hoang Hai nguyen Viet Tinh Faculty of Commerce Van Lang UniversityHo Chi Minh CityVietnam International Education Institute Van Lang UniversityHo Chi Minh CityVietnam

The 21st century is associated with the IndustrialRevolution 4.0 and the organic agriculture trend,making the utilization of high-quality fertilizers,abundant nutritional content,economical,and no affect to environment *** to the new concept,clean agricultural production and organic agricultural products are not allowed to excessively use synthetic chemicals such as chemical fertilizers,and plant protection drugs,but priority is to use manure,organic fertilizers,and natural mineral *** must meet the balanced nutritional requirements of crops,maintain,and improve the fertility of the ground,protect the surrounding ecosystem,and leave harmful effects in agricultural products,products with high quality,safe for users and high economic efficiency for *** achieve the above goal,the selection of a fertilizer supplier is an important decision,supporting the supply chain’s sustainable development,fertilizer supplier selection is a multicriteria decision making model,the decision maker must assess all qualitative and quantitative *** this paper,the author proposed an integer decision making model including Fuzzy Analytic Hierarchy Process(FAHP)and Complex Proportional Assessment of Alternatives(COPRAS)for fertilizer supplier *** weightings of the criteria are calculated by using FAHP,COPRAS is then applied for ranking some potential fertilizer *** efficiency of the proposed models is proved by a case study conducted in a farm located in the south of *** research is the first fertilizer supplier evaluation and se-lection model in Vietnam by interviewing experts and reviewing the ***-search result is to provide a case study on evaluating supplier in agricultural supply chain utilizing the model proposed by the combination of FAHP and COPRAS models.

关键词： Fertilizer industry optimization model fuzzy theory agricultural supply chain

Luminescent and magnetic properties of multifunctional europium(Ⅲ) complex based nanocomposite

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Journal of Rare Earths 2019年第11期37卷 1237-1241页

作者： Hoang thi Khuyen nguyen thanh Huong Tran Thu Huong Pham thi Lien Do thi Anh Thu nguyen thi Anh Huong Wieslaw Strek Le Quoc Minh Institute of Materials Science Vietnam Academy of Science and Technology18 Hoang Quoc VietCau CiayHanoiViet Nam Graduate University of Science and Technology Vietnam Academy of Science and Technology18 Hoang Quoc VietCau GiayHanoiViet Nam Department of Chemistry University of Natural SciencesHanoi National University19 Le Thanh TongHoan KiemHanoiViet Nam Institute of Low Temperature and Structure Research PASOkolna 2Wroclaw 50-422Poland Duy Tan University K7/25 Quang TrungDa DangViet Nam

The luminescent rare earth(RE)complex based multifunctional nanocomposites offer new potential applications of multimodal imaging(magnetic resonance imaging(MRI),fluorescent bioimaging,etc.)that can be associated with therapeutic *** this study,we report some results obtained with novel multifunctional Fe3O4/Si-amine/Eu(NTA)3 nanocomposites that are composed of europium(Ⅲ)complex with 1-(2-naphthoyl)-3,3,3-trifluoroacetone ligands(NTA)(Eu(NTA)3)and superparamagnetic Fe3O4 *** nanocomposites were functionalized with an amine group for biomedicine *** multifunctional Fe3O4/Si-amine/Eu(NTA)3 nanocomposites exhibit both good magnetic behavior of Fe3O4 nanoparticles as a core and strong fluorescent property of europium(Ⅲ)*** characterizations were analyzed by XRD,SEM,EDX and FTIR *** optical properties were studied in detail by UV-VIS spectra and luminescent emission *** magnetic property was estimated by *** effect of concentrations of luminescent Eu(NTA)3 complex on luminescent and magnetic properties is discussed.

关键词： Multifunctional nanocomposite Luminescence Magnetic Europium(Ⅲ)complex Fe3O4 Rare earths