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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

Biological methane production coupled with sulfur oxidation in a microbial electrosynthesis system without organic substrates

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Journal of Environmental Sciences 2022年第6期34卷 68-78页

作者： ha T.T.Dinh Hiromi Kambara Shuji Matsushita Yoshiteru Aoi Tomonori Kindaichi Noriatsu Ozaki Akiyoshi Ohashi Department of Civil and Environmental Engineering Graduate School of Advanced Science and EngineeringHiroshima University1-4-1KagamiyamaHigashihiroshimaHiroshima 739-8527Japan Faculty of Environment Ho Chi Minh City University of Natural Resources and Environment236 Le Van Sy1 WardTan Binh DistrictHo Chi Minh CityViet Nam Agricultural Technology Research Center Hiroshima Prefectural Technology Research Institute6869HaraHachihonmatsuHigashihiroshimaHiroshima 739-0151Japan Program of Biotechnology Graduate School of Integrated Sciences for LifeHiroshima University1-3-1KagamiyamaHigashihiroshimaHiroshima 739-8530Japan

Methane is produced in a microbial electrosynthesis system(MES) without organic substrates. However, a relatively high applied voltage is required for the bioelectrical *** this study, we demonstrated that electrotrophic methane production at the biocathode was achieved even at a very low voltage of 0.1 V in an MES, in which abiotic HS-oxidized to SO_(4)^(2-) at the anodic carbon-cloth surface coated with platinum powder. In addition, microbial community analysis revealed the most probable pathway for methane production from electrons. First, electrotrophic H_(2) was produced by syntrophic bacteria, such as Syntrophorhabdus, Syntrophobacter, Syntrophus, Leptolinea, and Aminicenantales, with the direct acceptance of electrons at the biocathode. Subsequently, most of the produced H_(2) was converted to acetate by homoacetogens, such as Clostridium and Spirochaeta 2. In conclusion,the majority of the methane was indirectly produced by a large population of acetoclastic methanogens, namely Methanosaeta, via acetate. Further, hydrogenotrophic methanogens,including Methanobacterium and Methanolinea, produced methane via H_(2).

关键词： Bioelectricity Homoacetogens Methane production Microbial electrosynthesis system Sulfur oxidation

Seasonal and geographical distribution of bacillary dysentery(shigellosis)and associated climate risk factors in Kon Tum Province in vietnam from 1999 to 2013

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Infectious Diseases of Poverty 2017年第1期6卷 1012-1022页

作者： Hu Suk Lee TTha Hoang Phuc Pham-Duc Mihye Lee Delia Grace Dac Cam Phung Vu Minh Thuc Hung Nguyen-viet International Livestock Research Institute(ILRI) Room 301-302B1 BuildingVan Phuc Diplomatic Compound298 Kim Ma StreetBa Dinh DistrictHanoiVietnam Department of Bacteriology National Institute of Hygiene and EpidemiologyHanoiVietnam Center for Public Health and Ecosystem Research Hanoi University of Public HealthHanoiVietnam Medical Microbiology Department The Royal Bournemouth HospitalBournemouthUK ILRI NairobiKenya Thanh Do University HanoiVietnam

Background:Bacillary dysentery(BD)is an acute bacterial infection of the intestine caused by Shigella spp.,with clinical symptoms ranging from fever to bloody diarrhoea to abdominal cramps to *** vietnam,enteric bacterial pathogens are an important cause of diarrhoea and most cases in children under 5 years of age are due to Shigella *** serogroups *** and *** are considered to be the most *** main objective of this study was to,for the first time,assess the seasonal patterns and geographic distribution of BD in vietnam,and to determine the climate risk factors associated with the incidence of BD in Kon Tum Province,where the highest rate of bacillary dysentery was observed from 1999 to ***:The seasonal patterns and geographic distribution of BD was assessed in vietnam using a seasonaltrend decomposition procedure based on *** addition,negative binomial regression models were used to determine the climate risk factors associated with the incidence of BD in Kon Tum Province,from 1999 to ***:Overall,incidence rates of BD have slightly decreased over time(except for an extremely high incidence in 2012 in the north of vietnam).The central regions(north/south central coast and central highlands)had relatively high incidence rates,whereas the northwest/east and Red River Delta regions had low incidence ***,seasonal plots showed a high peak in the mid-rainy reason and a second smaller peak in the early or late rainy *** incidence rates significantly increased between May and October(“wet season”)across the *** Kon Tum Province,temperature,humidity,and precipitation were found to be positively associated with the incidence of ***:Our findings provide insights into the seasonal patterns and geographic distribution of BD in vietnam and its associated climate risk factors in Kon Tum *** study may help clinicians and the general public to better understand the timings of outbr

关键词： Shigella Bacillary dysentery Incidence rate Seasonality Wet season Eco-regions Central regions vietnam

Monte Carlo simulation of a cone-beam CT system for lightweight casts

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Radiation Detection Technology and Methods 2021年第4期5卷 504-512页

作者： Thuy Duong Tran Ngoc ha Bui Kim Tuan Tran Ngoc Toan Tran Department of Nuclear Engineering and Environmental Physics School of Engineering PhysicsHanoi University of Science and Technology01 Dai Co VietHai Ba TrungHanoiVietnam vietnam Atomic Energy Institute 59 Ly Thuong KietHoan KiemHanoiVietnam

Cone-beam computed tomography(CBCT),a modern technique with many applications,is becoming increasingly important and essential in many areas of economics and *** equipment has been commercialized in both hardware and ***,having a device system suitable for a specific group of objects will be the *** work used Monte Carlo simulation to optimize the design of a Cone-beam Computed Tomography(CBCT)for lightweight and small-size *** affecting image quality such as radiation-source,flat-panel detector,and geometrical distance were *** results indicate that an X-ray generator with a focal spot size of 4×4µm^(2),high voltage of 240 kV,and a radiation intensity of 10^(13) photon/s with a flat panel CsI(Tl)detector of 0.3 mm thickness and a pixel size of 0.1–0.2 mm,is suitable for a CBCT to inspect small objects in *** Monte Carlo model was validated against experiments and to evaluate some characteristics of the existing system.

关键词： Cone-beam computed technology Monte Carlo simulation Lightweight casts in industry Applied radiation

Forest Change and Its Effect on Biomass in Yok Don National Park in Central Highlands of vietnam Using Ground Data and Geospatial Techniques

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Advances in Remote Sensing 2015年第2期4卷 108-118页

作者： Nguyen viet Luong Ryutaro Tateishi Nguyen Thanh Hoan To Trong Tu Space Technology Institute Vietnam Academy of Science and Technology Hanoi Vietnam Center for Environmental Remote Sensing Chiba University Chiba Japan Institute of Geography Vietnam Academy of Science and Technology Hanoi Vietnam

This paper assesses the changes in forest cover in Yok Don National Park of vietnam between 2004 and 2010, and the implications of such changes on the biomass stocks of this national park. Remote sensing and GIS tools along with the ground truth data collected from the field were employed for classifying the forest types of the study area from SPOT HRV satellite imagery for years 2004 and 2010. The total area considered in this study is 115.5 thousand ha. Five different categories of forests were identified. The results demonstrated that between 2004 and 2010, the Evergreen broad leaved rich quality forest decreased by 11.2 thousand ha (3.5 Mega tons of biomass) and the Dry open dipterocarps medium quality forest decreased by 15.3 thousand ha (2.5 Mega tons of biomass). In that time period, the Evergreen broad leaved medium quality forest increased by 3.2 thousand ha (0.8 Mega tons of biomass), the Evergreen broad leaved poor quality forest increased by 2.5 thousand ha (0.24 Mega tons of biomass), and the Dry open dipterocarps poor quality forest increased by 3.2 thousand ha (0.69 Mega tons of biomass). Total biomass of the study area decreased by 4.3 Mega tons.

关键词： Satellite Data SPOT HRV Land Cover Change Tropical Forest Biomass

Studies on sustainable features of vernacular architecture in different regions across the world:A comprehensive synthesis and evaluation

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Frontiers of Architectural Research 2019年第4期8卷 535-548页

作者： Anh Tuan Nguyen Nguyen Song ha Truong David Rockwood Anh Dung Tran Le Faculty of Architecture the University of Danang-University of Science and TechnologyDa NangViet Nam School of Architecture University of Hawaii at ManoaUSA Laborotoire des Technologies Innovantes(LTI) Universite de Picardie Jules VerneFrance

Due to the increasing pressure brought by recent global environmental problems,building designers are embracing regionalism and the knowledge of traditional structures,arguing that these structures are energy efficient and highly *** observe clear evidence of the increasing interest in vernacular architecture among the research *** study therefore aims to clarify the contents and issues raised in the studies on vernacular architecture and the knowledge and recommendations that can be derived from them.A database of the research is established by collecting many studies from primary *** data is carefully refined and categorized into a table where synthesized information is *** results of this study show an uneven geographic and climatic distribution of the studies;the trend in selecting research objectives and research objects;the choice of research methods with a clear shift towards quantitative research methods,and the generic findings from the database of the *** results can support diverse inquiries about vernacular architecture across the world and be used as a resource or an orientation to support numerous subsequent studies.

关键词： Vernacular architecture Traditional architecture Sustainable feature Research method Building design

Effects of low energy (160 keV) X-ray on microbial inactivation,sprouting inhibition and genetic variation in potato

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Food Bioscience 2022年第3期47卷 262-270页

作者： Nguyen An Son Nguyen Thi Nguyet ha Nguyen Thi Minh Sang Le Doan Dinh Duc Le Ngoc Trieu Faculty of Physic and Nuclear Engineering Da Lat UniversityViet Nam Dalat Vocational Training College Viet Nam Faculty of Biology Da Lat UniversityViet Nam

The effects of low energy X-ray irradiation on microbial inactivation,sprouting inhibition and genetic variation were *** was an inverse correlation between the exposure dose in range of 0 Gy–5000 Gy and the survival rate of *** dose of 1000 Gy seemed to be suitable for inactivation of microorganisms because the respective survival rate is relatively low (0.59%).Dose rate of 13.87 Gy/min was the most appropriate to inactivate the microorganisms,with the survival rate of 0.37%.Applying the irradiation dose of 1000 Gy and dose rate of 13.87 Gy/min,there was a significant sprouting inhibition of irradiated potatoes compared to the control for six months *** effect of irradiation dose (100–1200 Gy) and dose rate (8.63–19.62 Gy/min) on genetic variation of the irradiated samples was assessed by DNA fingerprints induced from using three molecular techniques including Random Amplified Polymorphic DNA (RAPD),Start Codon Targeted Polymorphism (SCoT) and CAAT box – derived polymorphism (CBDP).At the irradiation dose of 1000 Gy and dose rate of 13.87 Gy/min,the level of genetic variation was relatively low (4.85%).Thus,this treatment is a suitable condition of irradiation for potato treatment with the purpose of preservation.

关键词： Dose Dose rate Low energy X-ray Microbial inactivation Potato

The Statistical Distribution for 0-Deformed Crystal Lattice Vibration for Generic Atomic String

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Journal of Physical Science and Application 2014年第2期4卷 136-138页

作者： Nguyen Thi ha Loan Department of Physics Hanoi Pedagogical University No 2 Finh Phuc 280000 Viet Nam

In this paper, a g-deformation of crystal lattice vibration for generic atomic string is suggested. The expression for energy spectrum depends on g-deformed parameter have been obtained. The statistical distribution of g-deformed crystal lattice vibration is calculated and this result is very much different from there of q-deformed crystal lattice vibration.

关键词： Quantum crystal lattice vibration

Evaluating the yield of systematic screening for tuberculosis among three priority groups in Ho Chi Minh City,viet Nam

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Infectious Diseases of Poverty 2020年第6期9卷 16-28页

作者： Luan Nguyen Quang Vo Andrew James Codlin Rachel Jeanette Forse NgaThuy Nguyen Thanh Nguyen Vu Giang Truong Le Vinh Van Truong Giang Chau Do ha Minh Dang Lan Huu Nguyen Hoa Binh Nguyen Nhung viet Nguyen Jens Levy Knut Lonnroth SBertel Squire Maxine Caws Friends for International TB Relief 68B Nguyen Van Troi8Phu NhuanHo Chi Minh CityViet Nam Interactive Research and Development Ho Chi Minh CityViet Nam Ho Chi Minh City Public Health Association Ho Chi Minh CityViet Nam Pham Ngoc Thach Hospital Ho Chi Minh CityViet Nam National Lung Hospital Ha NoiViet Nam KNCV Tuberculosefonds The HagueThe Netherlands Department of Global Public Health Karolinska InstitutetStockholmSweden Department of Clinical Sciences Liverpool School of Tropical MedicineLiverpoolUK Birat Nepal Medical Trust LazimpatKathmanduNepal

Background: In order to end tuberculosis(TB),it is necessary to expand coverage of TB care services,including systematic screening ***,more evidence is needed for groups among whom systematic screening is only conditionally recommended by the World Health *** study evaluated concurrent screening in multiple target groups using community health workers(CHW).Methods:: In our two-year intervention study lasting from October 2017 to September 2019,CHWs in six districts of Ho Chi Minh City,viet Nam verbally screened three urban priority groups:(1)household TB contacts;(2)close TB contacts;and(3)residents of urban priority areas without clear documented exposure to TB including hotspots,boarding homes and urban *** persons were referred for further screening with chest radiography and follow-on testing with the Xpert MTB/RIF *** individuals with normal or without radiography results were tested on smear *** described the TB care cascade and characteristics for each priority group,and calculated yield and number needed to ***,we fitted a mixed-effect logistic regression to identify the association of these target groups and secondary patient covariates with TB treatment ***: We verbally screened 321020 people including 24232 household contacts,3182 social and close contacts and 293606 residents of urban priority *** resulted in 1138 persons treated for TB,of whom 85 were household contacts,39 were close contacts and 1014 belonged to urban priority area *** yield of active TB in these groups was 351,1226 and 345 per 100000,respectively,corresponding to numbers needed to screen of 285,82 and *** fitted model showed that close contacts[adjusted odds ratio(aOR)=2.07;95%CI:1.38–3.11;Phad a greater risk of active TB than household ***: The study detected a large number of un

关键词： Case detection Tuberculosis Active case finding Urban viet nam