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Journal of Coal Science & Engineering(China) 2009年第2期15卷 129-133页

作者： nguyen Xuan-Thao nguyen Tran-Tuan TRAN dinh-Kien Institute of Mining Science and Technology University of Mining and Geology

Underground coal mining activities in the Quangninh coal basin (in the North ofVietnam) have been carried out at a depth of-130 m to-150 m,and in the near future thismining depth will become-300 m and-500 *** with the increasing coal output,the quantity of methane and other mine gases emitted from coal beds during mining activitieswill grow bigger and *** to the forecast of the coal mining industry,ifmines go deeper downward,all underground coal mines in the Quangninh basin will beclassified into the mine group with the dangerous level of methane *** gascontrol and management operations with conventional ventilation are less effective andentail high *** of the main solutions is to carry out short,medium and longboreholes for controlling and recovering methane and other mine gases from coal bedsbefore mining *** of drilling activities for methane gas recovery from coalseams with horizontal bore holes at underground coal mines depends on many factors includingthe mine gas draining borehole layout at the roadways,gas content in the coalbeds,technologies for mine gas draining boring activities,and so *** gas existsin the coal beds under the adhesive state with stable physical and chemical *** orderto recover these gases,it is necessary to carry out boreholes and create artificial joints(collecting pits) in coal beds with the impulse method (hydraulic separation method).

关键词：地下煤矿甲烷排放钻孔技术越南危险煤层开采应用开发

Incorporation of hydroxyapatite in crosslinked gelatin/chitosan/poly(vinyl alcohol) hybrids utilizing as reinforced composite sponges, and their water absorption ability

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Progress in Natural Science:Materials International 2021年第5期31卷 664-671页

作者： Thi Sinh Vo Tran Thi Bich chau Vo Truong Sinh nguyen Nhan Duy Pham School of Mechanical Engineering Sungkyunkwan University Department of Chemistry Memorial University of Newfoundland Department of Industrial Management Can Tho University

The crosslinked gelatin/chitosan/poly(vinyl alcohol)/hydroxyapatite(GEL/CTS/PVA/HAp, GCPH) sponges were fabricated by a freeze-drying method to yield the reinforced composite sponges with proper features. The porosity value and pore size of the crosslinked GCPH sponges reached ～80% and 50–100 μm, respectively, which can be an appropriate range to allow cells to migrate into the reinforced composite sponges in the tissue engineering technology. Besides, the proper bonding presence between HAp particles and the crosslinked polymeric matrix or the crosslinked network formation between the polymers were also proved through fourier-transform infrared spectroscopy(FTIR), X-ray diffraction(XRD) and thermal gravimetric(TG/DTG) analysis. Owing to incorporation of HAp particles and good distribution of HAp particles inside the crosslinked polymeric matrix, their mechanical properties were improved through the determination of compression tests. Concomitantly, their water absorption ability reached effectively in both the distilled water and Na Cl solution, and their recovery also maintained well for 10 absorbing–squeezing cycles to be considered as an effective reusability for the crosslinked sponge ***, the crosslinked GCPH sponge prepared in the present study can become a potential candidate to apply especially in the biomedical/medical applications and tissue engineering technology.

关键词： Reinforced composite sponge Gelatin Chitosan Poly(vinyl alcohol) Hydroxyapatite Water absorption ability Reusability

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

Facile synthesis of FeFe2O4 magnetic nanomaterial for removing methylene blue from aqueous solution

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Progress in Natural Science:Materials International 2019年第6期29卷 648-654页

作者： Van-Phuc dinh Ngoc Quyen Tran nguyen-Que-Tran Le Quang-Huy Tran Trinh Duy nguyen Gr EEN), nguyen Tat Thanh University Van Tan Le Future Materials and Devices Laboratory Institute of Fundamental and Applied Sciences Duy Tan University Institute of Applied Materials Science VAST Graduate University of Science and Technology VAST Le Quy Don–LBT Highschool Bien Hoa City Dong Nai province Center of Excellence for Green Energy and Environmental Nanomaterials (CE Industrial University of Ho Chi Minh City

A facile and simple chemical precipitation method was utilized to synthesize FeFe2O4magnetic nanomaterial for removing methylene blue（MB） from aqueous solution. Characterizations of this material were examined by using XRD, SEM, FT-IR, TGA-DTG and BET methods. Factors affecting the uptake of methylene blue, including p H, adsorption time, and MB initial concentration were also studied. The measured data were fitted by using four isotherm models including Langmuir, Freundlich, Sips and Temkin. Results showed that the Sips model offers the best fit to the data. In addition, the monolayer MB adsorption capacity obtained from the Langmuir model was 42.35 mg g-1under the optimal conditions of p H = 10 and adsorption time = 80 min. In particular, the uptake of MB onto FeFe2O4magnetic nanomaterial obtained from the kinetic and mechanism studies of the adsorption was in good agreement with prediction of the pseudo-first-order model, whereas the electrostatic interaction was found to play a primary mechanism.

关键词： FeFe2O4 magnetic nanomaterial Adsorption Methylene blue Adsorption mechanism

Morphological Change in the Northern Red River Delta,Vietnam

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Journal of Ocean University of China 2018年第6期17卷 1272-1280页

作者： BUI Vuong Van FAN Daidu nguyen Dac Ve TRAN dinh Lan TRAN Duc Thanh HOANG Van Long nguyen Thi Hong Hanh Institute of Marine Environment and Resources Vietnam Academy of Science and TechnologyHaiphong 18000Vietnam State Key Laboratory of Marine Geology Tongji UniversityShanghai 200092China Hanoi University of Mining and Geology Hanoi 10000Vietnam Graduate University of Science and Technology Vietnam Academy of Science and TechnologyHanoi 10000Vietnam

Coastal erosion has become a worldwide concern, typically in the densely populated Asian mega-river deltas. Severe coastal erosion in the southern Red River Delta(RRD) has been intensively studied. Coastal morphological change in the northern RRD was examined in detail through DEM(Digital Elevation Model) analysis based on time series of bathymetrical maps(1965–2004) and Landsat images(1975–2015) in this study. The results show that the northern RRD is featured by rapid coastal accretion in the past few decades, although suspended sediment flux has dropped by roughly 60% after the completeness of Hoa Binh Dam(HBD) in 1988 and relative sea level rose at 1.9 mm yr^(-1). However, accretion at the outer part of subtidal shoals and platforms was observed to slow down quickly or even turned into erosion in the last two decades. The resuspended sediments from the erosion zone can be transported landward to replenish the inner coastal zone, keeping the latter accretion in the near future to compensate for the sediment discharge decrease from the river. However, this lag effect should be terminated soon if other adverse effects go worse, e.g., damming rivers, sea-level rising, strengthening storms, land reclamation and other poor-designed coastal engineering. Coastal planners and managers should pay full attention to these changes.

关键词： Morphological change DEM coastal erosion coastal engineering coastal management tide-dominated Red River Delta

A novel approach for synthesis of hierarchical mesoporous Nd2O3 nanomaterials

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Journal of Rare Earths 2017年第7期35卷 677-682页

作者： Le Huu Trinh dinh Quang Khieu Hoang Thai Long Tran Thai Hoa Duong Tuan Quang nguyen Duc Cuong College of Sciences Hue University 77 Nguyen Hue Hue City Viet Nam Faculty of Hospitality and Tourism Hue University 22 Lam Hoang Hue CityViet Nam College of Education Hue University 34 Le LoL Hue City Viet Nam

A novel route to the fabrication of hierarchical mesoporous Nd_2O_3 nanostructures including nanospheres and nanoporous network was described. Their structure and morphology evolution of the as-synthesized materials were determined by various techniques such as scanning electron microscopy, transmission electron microscopy, high-resolution transmission electron microscopy, X-ray diffraction, energy-dispersive X-ray spectroscopy, Fourier transforminfrared spectra, nitrogen adsorption/desorption isotherm, and a formation mechanism was proposed. The results revealed that the Nd_2O_3 nanospheres had the diameter of 300 nm, which were composed of small primary nanoparticles（NPs） with the size of 10 nm. The nanoporous structure also formed the NPs of ca. 10 nm which were connected with each other to form a three-dimensional（3D） texture. This simple and mild approach to fabricate hierarchical mesoporous Nd_2O_3 nanostructures could be easily scaled up and potentially extended to synthesize other oxide hierarchical structures.

关键词： Nd2O3 hierarchical nanostructures nanospheres nanoporous network rare earths

Ecohealth research in Southeast Asia: past, present and the way forward

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Infectious Diseases of Poverty 2015年第1期4卷 36-48页

作者： Hung nguyen-Viet Siobhan Doria dinh Xuan Tung Hein Mallee Bruce A Wilcox Delia Grace International Livestock Research Institute(ILRI) 17A Nguyen Khang StreetTrung Hoa WardCau Giay DistrictHanoiVietnam Centre for Public Health and Ecosystem Research(CENPHER) Hanoi School of Public Health(HSPH)138 Giang Vo StreetHanoiVietnam Swiss Tropical and Public Health Institute(Swiss TPH) Socinstrasse 57Basel CH-4002Switzerland University of Basel Basel 4001Switzerland National Institute and Animal Sciences HanoiVietnam Research Institute for Humanity and Nature(RIHN) KyotoJapan Integrative Education and Research Programme Faculty of Public HealthMahidol UniversityBangkok 10400Thailand Division of Infectious Diseases and Global Health Cummings School of Veterinary MedicineTufts UniversityNorth GraftonMA 01536USA International Livestock Research Institute(ILRI) NairobiKenya

Ecohealth is a comprehensive approach to understanding health at its human,animal and environmental interface in a socio-ecological systems *** approach was introduced widely in Southeast Asia(SEA)by the Canadian International Development Research Centre(IDRC)in the late *** at addressing the problem of emerging infectious diseases(EIDs),numerous such projects and activities have been generated throughout the *** is increasingly converging with the One Health approach,as both movements emphasise a holistic understanding to *** conducted a scoping review by considering all of the Ecohealth programmes,initiatives and projects that have been implemented in SEA since the introduction of the approach,and also gathered information from peer-reviewed *** objective of this paper is to review Ecohealth activities within SEA over the last 10 years to address the lessons learned,challenges faced and the way forward for Ecohealth in the *** range from those focusing purely on capacity,projects focusing on research and projects covering *** to date include,for example,research contributing to the field of infectious diseases in relation to social ecological factors and associated urbanisation and agricultural *** remain at the project design and implementation level,in the available capacity and coordination to develop Ecohealth research teams in the countries,gauging teams’assimilation of Ecohealth’s underlying tenets and their translation into sustainable disease prevention and control,as well as in the ability to scale up Ecohealth *** suggest that the way forward for Ecohealth should be from a regional perspective in terms of research,training and policy translation using Ecohealth in combination with the One Health approach.

关键词： Ecohealth One health Southeast Asia Interdisciplinary Transdisciplinary Scientific partnership Capacity building Network Ecohealth content

Thermodynamic Simulation on the Change in Phase for Carburizing Process

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Computers, Materials & Continua 2021年第7期68卷 1129-1145页

作者： Anh Tuan Hoang Xuan Phuong nguyen Osamah Ibrahim Khalaf Thi Xuan Tran Minh Quang chau Thi Minh Hao Dong Duong Nam nguyen Ho Chi Minh city University of Technology(HUTECH) HoVietnam Ho Chi Minh city University of Transport Ho Chi Minh cityVietnam Al-Nahrain University Al-Nahrain Nanorenewable Energy Research CenterBaghdadIraq Hanoi University of Science and Technology HanoiVietnam Industrial University of Ho Chi Minh City(IUH) Ho Chi Minh cityVietnam Vietnam Maritime University HaiphongVietnam

The type of technology used to strengthen the surface structure of machine parts,typically by carbon-permeation,has made a great contribution to the mechanical engineering industry because of its outstanding advantages in corrosion resistance and enhanced mechanical and physical ***,carbon permeation is considered as an optimal method of heat treatment through the diffusion of carbon atoms into the surface of alloy *** study presented research results on the thermodynamic calculation and simulation of the carbon permeability *** Fick’s law,the paper calculated the distribution of carbon concentration in the alloy steel after it is absorbed from the surface into the internal of the *** the SYSWELD software,an analysis was performed on the carbon permeability process to determine the distribution of carbon concentrations in 20CrMo steel that was then followed by a detailed analysis of the microstructure of the sample post the carburizing *** to the calculation results,the surface carbon content was 0.9%and steadily decreased into the *** 3 hours,the depth of the absorbent layer was measured at 0.5 mm for both the cylindrical and cubic *** analyzing the phase,the distribution of martensite phases such as ferrite/pearlite and residual austenite was also determined after the carburizing process.

关键词： Carburizing process 20CrMo steel thermodynamic analysis microstructure formation carbon concentration

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

Upconversion luminescence of Gd2O3:Er3+and Gd2O3:Er3+/silica nanophosphors fabricated by EDTA combustion method

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Journal of Rare Earths 2019年第11期37卷 1126-1131页

作者： Le Quoc Minh Tran Kim Anh nguyen Duy Hung Pham Thi Minh chau nguyen Thi Quy Hai Ho Van Tuyen Vu Thi Thai Ha Vu Duc Tu Wieslaw Strek Institute of Theoretical and Applied Research Duy Tan UniversityDa Nang 55000Viet Nam Advanced Institute for Science and Technology Hanoi University of Science and Technology1 Dai Co VietHai Ba TrungHanoiViet Nam Institute of Materials Science Vietnam Academy of Science and Technology18 Hoang Quoc Viet RoadCau Giay DistrictHanoiViet Nam Institute of Low Temperature and Structure Research Polish Academy of Science 2 OkolnaWroclawPoland

Gd2O3:Er^3+nanophosphors were fabricated by the combustion method in presence of Na2 ethylene diamine tetra acetic acid(EDTA-Na2)as fuel at not high temperature(≤350℃)within a very short time of 5 *** added concentration of Er^3+ions in Gd2O3 matrix was changed from 0.5 mol%to 5.0 mol%.The X-ray diffraction pattern of samples indicates the monoclinic structure of Gd2O3:Er^3+.The morphology and chemical composition analysis of the Gd2O3:Er^3+samples are characterized by a field emission scanning electron microscope(FESEM)and a Fourier-transform infrared spectrometer(FTIR).The photoluminescence(PL),photo luminescence excitation(PLE)and upconversion(UC)at room temperature of the prepared materials with different concentrations of Er^3+were *** PL of Gd2O3:Er^3+nanomaterials are shown in visible at 545,594,623,648,688 nm under excitation at 275 *** emission bands from transitions of Er^3+from 2P3/2 to 4F9/2 are observed,UC luminescent spectra of the Gd2O3:Er^3+/silica nanocomposites under 976 nm excitation show the bands at 548 and 670 *** influence of excitation power at 980 nm for transitions were measured and *** results indicate that the upconversion process of Gd2O3:Er^3+/silica is two photons absorption *** low temperature dependence of UC luminescent intensities of the main bands of Gd2O3:Er^3+was investigated towards development of a nanotemperature sensor in the range of 10-300 K.

关键词： Upconversion luminescence Gd2O3:Er3+ Gd2O3:Er3+/silica Nanophosphors EDTA combustion Rare earths