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安庆-贵池矿集区宝树尖铜多金属矿床成因:来自岩石地球化学及年代学的约束

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岩石学报 2020年第1期36卷 184-204页

作者：汪海赵壮杨晓勇古黄玲郑荥 NGUYEN tuan anh 中国科学技术大学地球和空间科学学院湖南工业大学安徽省地勘局324地质队

宝树尖铜多金属矿床位于长江中下游成矿带安庆-贵池矿集区,是一个新发现的矽卡岩型矿床。本文主要通过岩石地球化学和年代学方法来解释矿床的成因。锆石U-Pb年代学研究表明,宝树尖岩体形成于148.6±3.2Ma,是长江中下游燕山晚期的产物,... 详细信息

宝树尖铜多金属矿床位于长江中下游成矿带安庆-贵池矿集区,是一个新发现的矽卡岩型矿床。本文主要通过岩石地球化学和年代学方法来解释矿床的成因。锆石U-Pb年代学研究表明,宝树尖岩体形成于148.6±3.2Ma,是长江中下游燕山晚期的产物,为长江中下游成矿带内发现的一个较早的中酸性含矿侵入体。对于该成矿岩体及矿床的深入研究,将为区内燕山期岩浆活动及成矿提供一个不可多得的范例。岩石属于高钾钙碱性、钙碱性系列,地球化学特征显示为埃达克质岩;矿区矿石金属硫化物以方铅矿、闪锌矿、黄铜矿和黄铁矿为主,非金属矿物有透辉石、石榴石、透闪石、石英、钠长石、方解石、绿泥石和绿帘石等。矿区侵入岩主要由闪长岩和闪长玢岩组成,总体上具有高的全碱含量,低的Al2O3、TiO 2、Fe2O3^T和P2O5含量,富集大离子亲石元素(U、Rb、Sr)和高场强元素(Nb、Ta、Ti),轻稀土富集、重稀土亏损。岩石具有高的La/Yb、Sr/Y比值,低的Yb、Y含量,属于埃达克质岩。锆石稀土元素配分图显示典型的轻稀土亏损、重稀土富集。锆石Ti温度计表明岩石形成的平均温度为674.3℃。全岩Sr-Nd-Pb同位素特征表明岩石起源于俯冲洋壳的部分熔融。矿石黄铁矿δ34 S变化范围为7.6‰~9.6‰,表明成矿物质来源于岩浆热液和地层。锆石Eu异常特征和Ce^4+/Ce^3+比值表明形成岩石的岩浆具有高氧逸度,这有利于Cu、Au、Zn等成矿物质的迁移。结合区域地质背景,我们认为宝树尖矽卡岩型矿床的形成过程是:燕山期太平洋板块向中国东部俯冲,导致板片部分熔融产生埃达克质岩浆,最后经埃达克质岩浆分异形成的含矿气水热液在地壳浅部与上覆寒武系灰岩发生接触交代作用。

关键词：宝树尖多金属矿床安庆贵池矿集区埃达克岩锆石U-Pb定年 Sr-Nd-Pb同位素俯冲洋壳长江中下游

Calibration of a neutron dose rate meter in various neutron standard fields

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Nuclear Science and Techniques 2020年第6期31卷 75-82页

作者： tuan Khai Nguyen Hoai-Nam Tran Quynh Ngoc Nguyen Thi My Linh dang Van Loat Bui Thiansin Liamsuwan Ngoc-Thiem Le Vietnam Agency for Radiation and Nuclear Safety 113 Tran Duy HungHanoi 100000Vietnam Institute of Fundamental and Applied Sciences Duy Tan UniversityHo Chi Minh 700000Vietnam Faculty of Natural Sciences Duy Tan University3 Quang TrungDa Nang 550000Vietnam Institute for Nuclear Science and Technology VINATOM179 Hoang Quoc VietHanoi 100000Vietnam Faculty of Physics VNU University of Science334 Nguyen TraiHanoi 100000Vietnam Nuclear Research and Development Division Thailand Institute of Nuclear TechnologyOngkharakNakorn NayokThailand 7 Faculty of Medicine and Public HealthHRH Princess Chulabhorn College of Medical ScienceChulabhorn Royal AcademyBangkokThailand

This paper presents the calibration of a neutron dose rate meter and the evaluation of its calibration factors(CFs)in several neutron standard fields(i.e.,two standard fields with bare sources of252Cf and241Am-Be,and five simulated workplace fields with241Am-Be moderated sources).The calibration in standard fields with bare sources was conducted by following the recommendations of the ISO 8529 *** measured total neutron ambient dose equivalent rates,denoted as H*(10)tot,were analyzed to obtain direct components,denoted as H*(10)dir,using a reduced fitting *** CF was then calculated as the ratio between the conventional true value of the neutron ambient dose equivalent rate in a free field,denoted as H*(10)FF,and the value of H*(10)*** contrast,in the simulated workplace neutron fields,the calibration of the neutron dose rate meter was conducted by following the ISO 12789 *** CF was calculated as the ratio between the values of H*(10)totmeasured by a standard instrument(i.e.,Bonner sphere spectrometer)and the neutron dose rate *** CF values were obtained in the range of 0.88–*** standard uncertainties(k=1)of the CFs were determined to be in the range of approximately 6.6–13.1%.

关键词： Neutron standard fields Neutron dose rate meter Calibration factor 252Cf source 241AmBe source

Effect of Poly-Alkylene-Glycol Quenchant on the Distortion, Hardness, and Microstructure of 65Mn Steel

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Computers, Materials & Continua 2021年第6期67卷 3249-3264页

作者： Thi Xuan Tran Xuan Phuong Nguyen Duong Nam Nguyen Dinh Toai Vu Minh Quang Chau Osamah Ibrahim Khalaf anh tuan Hoang Hanoi University of Science and Technology HanoiVietnam Ho Chi Minh City University of Transport Ho Chi Minh CityVietnam Vietnam Maritime University HaiphongVietnam Industrial University of Ho Chi Minh City(IUH) Ho Chi Minh CityVietnam Al-Nahrain Nanorenewable Energy Research Center Al-Nahrain UniversityBaghdadIraq Ho Chi Minh city University of Technology(HUTECH) Ho Chi Minh CityVietnam

Currently,the 65Mn steel is quenched mainly by oil *** though the lower cooling rate of oil compared to water reduces the hardness of steel post quenching,the deforming and cracking of parts are often *** the other hand,the oil media also has the disadvantage of being ammable,creating smoke that adversely affects the *** poly alkylene glycol(PAG)polymer quenchant is commonly used for quenching a variety of steels based on its advantages such as non-ammability and exible cooling rate subjected to varying concentration and stirring *** article examines the effect of PAG polymer quenching solution(with concentrations of 10%and 20%)on deformation,hardness,and microstructure of C-ring samples made of 65Mn ***,the performance of PAG polymer quenchant is also compared with those of two common quenching solutions:Water and *** cooling in water,the C-ring samples had the largest deformation and 2 times higher than the results obtained when a 10%PAG solution was *** particular,similar levels of deformation on the C-ring samples were observed in both cases of 20%PAG solution and oil as the primary quenching ***,the hardness level measured between the sampled parts quenched in the 20%PAG solution appeared to be more uniform than that obtained from the oil-quenched *** study of the microscopic structure of steel by optical microscopy combined with X-ray diffraction showed that the water hardened sample exhibited cracks and comprised of two phases,martensite and retained *** to the results of Electron Back Scattering Diffraction(EBSD)analysis and backscattering electronic image(BSE),the content of austenite residue in the sample when the sample was cooled in PAG 10 and 20%solution was 3.21%and 4.73%,respectively and smaller than the measurements obtained from oil quenching ***,the 65Mn steel is cooled in 20%PAG solution for high hardness and more evenly distributed than when it is q

关键词： Polyethylene glycol electron backscattering diffraction quenching media cooling rate backscattering electronic image

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

Hybrid model to optimize object-based land cover classification by meta-heuristic algorithm:an example for supporting urban management in Ha Noi,Viet Nam

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International Journal of Digital Earth 2019年第10期12卷 1118-1132页

作者： Quang-Thanh Bui Manh Pham Van Nguyen Thi Thuy Hang Quoc-Huy Nguyen Nguyen Xuan Linh Pham Minh Hai Tran anh tuan Pham Van Cu Center for Applied Research in Remote sensing and GIS(CARGIS) VNU University of ScienceHa NoiViet Nam VNU University of Science Ha NoiViet Nam Vietnam Institute of Geodesy and Cartography Ha NoiViet Nam Ministry of Education and Training Ha NoiViet Nam

This study proposed a novel object-based hybrid classification model named GMNN that combines Grasshopper Optimization Algorithm(GOA)and the multiple-class Neural network(MNN)for urban pattern detection in Hanoi,*** bands of SPOT 7 image and derivable NDVI,NDWI were used to generate image segments with associated attributes by PCI Geomatics *** segments were classified into four urban surface types(namely water,impervious surface,vegetation and bare soil)by the proposed ***,three training and validation datasets of different sizes were used to verify the robustness of this *** all tests,the overall accuracies of the classification were approximately 87%,and the Area under Receiver Operating Characteristic curves for each land cover type was ***,the performance of this model was examined by comparing several statistical indicators with common benchmark *** results showed that GMNN out-performed established methods in all comparable *** results suggested that our hybrid model was successfully deployed in the study area and could be used as an alternative classification method for urban land cover *** a broader sense,classification methods will be enriched with the active and fast-growing contribution of metaheuristic algorithms.

关键词： Urban remote sensing object-based classification neural network grasshopper optimization algorithm

Gravitationally lensed extended sources: the case of QSO RXJ0911

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Research in Astronomy and Astrophysics 2013年第7期13卷 803-814页

作者： Do Thi Hoai Pham Tuyet Nhung Pham tuan anh Frederic Boone Pierre Darriulat Pham Ngoc Diep Pham Ngoc Dong Nguyen Van Hiep Nguyen Thi Thao VATLY INST179Hoang Quoc VietCau GiayHanoiVietnam IRAP 14avenue Edouard BelinF31400 ToulouseFrance

After a brief reminder of the mechanism of gravitational lensing of ex- tended sources, the particular case of the host galaxy of QSO RXJ0911, a high red-shift （z - 2.8） quadruply imaged quasar, is explored. The non linearity of the problem, together with the proximity of the source to a cusp of the lens inner caustic, has impor-tant consequences on the dependence of the image appearance on the size and shape of the source. Their expected main features and their interpretation in terms of source extension and shape are investigated in a spirit of simplicity and in preparation for the analysis of high sensitivity and spatial resolution images that will soon be within reach with the completion of the Atacama Large Millimeter/submillimeter Array （ALMA）. In particular, the information on source size carded by relative image brightness is dis-cussed. Extension of the results to other types of quadruply imaged quasars is briefly considered.

关键词： gravitational lensing - galaxies: high-redshift

Micro-satellite Constellation The Challenges and the Possible Contribution of VNSC

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Journal of Geological Resource and Engineering 2014年第2期2卷 107-110页

作者： Vu Viet Phuong Pham anh tuan Vietnam National Satellite Center Vietnam Academy of Science and Technology Hanoi 10000 Vietnam

Examining Modal Shift to Public Transport in Developing Asian Cities:A Case Study in Hanoi City,Vietnam

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Journal of Traffic and Transportation Engineering 2023年第4期11卷 179-191页

作者： Vu anh tuan Vietnamese-German Transport Research Centre Vietnamese-German UniversityBình Dương 75000Vietnam

Quite many Asian cities are facing the issues of motorcycle dominance,and to solve it these cities are developing urban mass rapid transit systems(i.e.,BRT and MRT)with an intention to attract a large number of motorcycle and car ***,there might be uncertainties in shifting private transport users to new public transport systems,thereby risking the effectiveness of the investment in public *** study aims to examine the possibilities of modal shift to public transport by exploring current patterns of people’s travel behavior and anticipating their mode choice changes under policy intervention *** City,a typical motorcycle-dominated city in Asia,is selected for a case study.A stated preference survey is conducted and SP/RP mode choice models are estimated for different segments of urban transport *** is revealed that a significant number of private transport users might still stick to motorcycle and car use despite aggressive improvements of public transport in the *** chaining behavior and presence of school kid(s)in the family may prevent family members from shifting to public transport.A longer travel distance may not necessarily lead to a higher modal shift away from *** findings would be helpful to guide policy making towards sustainable development of public transport systems and effective management of private transport in developing cities,especially whose motorcycles are rapidly increasing and being dominant.

关键词： Public transport BRT transportation management

Biomass accumulation of Panax vietnamensis in cell suspension cultures varies with addition of plant growth regulators and organic additives

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Asian Pacific Journal of Tropical Medicine 2017年第9期10卷 907-915页

作者： tuan Tran Trong Dieu-Hien Truong Hoang Chinh Nguyen Dieu-Thai Tran Huyen-Trang Nguyen Thi Giap Do dang Ho Nguyen Huu Plant Cell Technology Department Institute of Tropical BiologyVietnam Academy of Science and Technology9/621 Ha Noi HighwayLinh TrungThu DucHo Chi Minh CityViet Nam Faculty of Applied Sciences Ton Duc Thang University19 Nguyen Huu ThoTan PhongDistrict 7Ho Chi Minh CityViet Nam Genetic Engineering Department Institute of Tropical BiologyVietnam Academy of Science and Technology9/621 Ha Noi HighwayLinh TrungThu DucHo Chi Minh CityViet Nam

Objective: To evaluate the impact of plant growth regulators including kinetin(KN),benzyl adenine and naphthalene acetic acid, yeast extract and casein hydrolyzate on biomass accumulation of Vietnamese ginseng Panax vietnamensis(P. vietnamensis) in cell suspension ***: Cell suspension cultures were established from friable calluses derived from leaves and petioles of 3-year-old in-vitro P. vietnamensis plants. The cell suspension cultures were grown in Murashige and Skoog basal media supplemented with various concentrations of KN, benzyl adenine, naphthalene acetic acid, and yeast extract and casein ***: All tested factors generated an increase in the cell biomass of P. vietnamensis in suspension culture, but the impact of each varies depended on the factor type, concentration, and incubation period. Addition of 2.0 mg/L KN resulted in the largest biomass increase after 24 d,(57.0 ± 0.9) and(3.1 ± 0.1) mg/m L fresh and dry weight, respectively,whereas addition of benzyl adenine or naphthalene acetic acid produced optimum levels of Panax cell biomass at 1.0 and 1.5 mg/L, respectively. Addition of the elicitor yeast extract led to a 1.4–2.4 fold increase in biomass of P. vietnamensis, while addition of casein hydrolyzate enhanced biomass accumulation 1.8–2.6 ***: The addition of each factor causes significant changes in biomass accumulation of P. vietnamensis. The largest biomass accumulation is from cultures grown in MS media containing 2.0 mg/L KN for 24 d. The outcome of the present study provides new insights into the optimal suspension culture conditions for studies on the in vitro cell biomass production of P. vietnamensis.

关键词：人参属 vietnamensis 种房间暂停文化种管理者酵母摘录酷蛋白 hydrolyzate 生物资源