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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

Genetic diversity and conservation of two threatened dipterocarps(Dipterocarpaceae) in southeast Vietnam

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Journal of Forestry Research 2019年第5期30卷 1823-1831页

作者： dinh-Duy Vu Thi Tuyet-Xuan Bui Minh-duc nguyen Syed Noor Muhammad Shah dinh-Giap Vu Yi Zhang Minh-Tam nguyen Xiao-Hua Huang College of Forestry Northwest A&F UniversityYanglingShaanxi 712100People’s Republic of China Vietnam National Museum of Nature Vietnam Academy of Science and Technology(VAST)18 Hoang Quoc VietCau GiayHanoiVietnam Institute of Ecology and Biological Resource Vietnam Academy of Science and Technology(VAST)18 Hoang Quoc VietCau GiayHanoiVietnam Department of Horticulture Faculty of AgricultureGomal UniversityDera Ismail KhanPakistan Institute of Natural Products Chemistry Vietnam Academy of Science and Technology(VAST)18 Hoang Quoc VietCau GiayHanoiVietnam

Two threatened dipterocarp species,Dipterocarpus costatus and Dipterocarpus alatus are well-known endangered species in lowland forests of southeastern Vietnam,primarily from habitat loss and over-exploitation of their *** develop conservation strategies for these species,we analyzed 242 samples using nine microsatellite markers to determine the genetic variability within and among five populations of *** and three of ***,representing the natural range of dipterocarps in Southeast *** indicated low levels of genetic variability within populations with an average gene diversity of 0.223 for *** and 0.152 for *** of bottleneck tests indicated a reduction in population size of both species(P>0.05).Genetic differentiation among populations was high(FST=0.347 for *** and 0.274 for ***),indicating limited gene flow(Nm=0.662 for *** and 0.47 for ***)and isolated populations related to geographical *** of molecular variance showed high genetic variation within populations(72.92%for *** and 60.81%for ***)compared to among *** analysis and UPGMA tree also indicated the two optimal genetic clusters related to geographical *** results will provide a platform for the conservation,management and restoration of these species.

关键词： Dipterocarps Genetic conservation Gene diversity SSR primers

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

Antibiotic usage in surgical sperm retrievals among IVF centers

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Asian Journal of Andrology 2022年第6期24卷 633-638页

作者： Le Dang Khoa Ngo dinh Trieu Vy nguyen Minh Tai Loc Le duc Thang Dang Tuan Anh nguyen Phuc Hieu Giang Huynh Nhu nguyen dinh Tao Le Hoang David J Handelsman IVFTA Tam Anh General HospitalHo Chi Minh 700000Vietnam IVFTA Tam Anh General HospitalHa Noi 100000Vietnam IVF Center 16A Ha Dong HospitalHa Noi 100000Vietnam ANZAC Research Institute University of Sydney and Concord Repatriation General HospitalHospital RoadConcordNSW 2139Australia

Surgical sperm retrieval(SSR)is currently one of the most common procedures in in vitro fertilization(IVF).However,a gap between the guidelines and routine clinical practice regarding antibiotic use in sSR,which might lead to antibiotic resistance,is a challenging problem worldwide.A cross-sectional survey was conducted from May 1,2021,to July 15,2021,to investigate antibiotic usage by medical professionals when performing SSR in IVF centers in *** confidential questionnaire comprised 12 items,including characteristics of the study population,awareness of antimicrobial resistance,attitude toward prescribing antibiotics,and current practice of prescribing antibiotics when performing *** were completed by 30 of 45 registered IVF centers(66.7%).Among 67 physicians working at those centers,the age and work-experience years(mean±standard deviation[s.d.])were 38.6±6.6 years and 11.2±7.0 years,*** 60%of them held a degree in Obstetrics and Gynecology,and over four-fifths were *** respondents"often/very often/always"raised awareness of antimicrobial resistance to their patients(83.3%),but only half of them"often/occasionally"prescribed antibiotics to patients with SSR in cases where the prescription would be *** one-tenth of respondents followed the recommendation from the American Urological Association using"prophylaxis only"for SSR *** more invasive SSR,physicians tended to prescribe more complicated and sometimes inappropriate *** conclusion,antibiotic usage in SSR was not always appropriate among IVF *** studies may define specific recommendations for regimens,intervention strategies,and programs to promote appropriate antibiotic use for SSR patients among IVF specialists.

关键词： antibiotic usage in vitro fertilization prophylaxis surgical sperm retrieval treatment

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

High Temperature Corrosion of Fe-C-S Cast Irons in Oxidizing and Sulfidizing Atmospheres

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Journal of Materials Science & Technology 2008年第3期24卷 327-329页

作者： Thuan-dinh nguyen Dong-Bok LEE School of Advanced Materials Science and Engineering Sungkyunkwan University

The corrosion behavior of spheroidal graphite and flake graphite cast irons was studied in oxidizing and sulfidizing atmospheres between 600 and 800℃ for 50 h. The corrosion rate in the sulfidizing atmosphere was faster than that in air above 700℃, due to the formation of the Fe0.975S sulfide. The corrosion rate of the spheroidal graphite cast iron was similar to that of the flake graphite cast iron.

关键词： Cast iron Oxidation Sulfidation

Determination of Helmert transformation parameters for continuous GNSS networks:a case study of the Géoazur GNSS network

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Geo-Spatial Information Science 2023年第1期26卷 125-138页

作者： dinh Trong Tran Jean-Mathieu Nocquet Ngoc Dung Luong dinh Huy nguyen Department of Geodesy and Geomatics Engineering Hanoi University of Civil EngineeringHanoiVietnam UniversitéCôte d’Azur CNRSObservatoire de la Côte d’AzurIRDValbonneFrance

In this paper,we propose an approach to determine seven parameters of the Helmert transfor-mation by transforming the coordinates of a continuous GNSS network from the World Geodetic System 1984(WGS84)to the International Terrestrial Reference *** includes(1)convert-ing the coordinates of common points from the global coordinate system to the local coordinate system,(2)identifying and eliminating outliers by the Dikin estimator,and(3)estimating seven parameters of the Helmert transformation by least squares(LS)estimation with the“clean”data(*** removed).Herein,the local coordinate system provides a platform to separate points’horizontal and vertical ***,the Dikin estimator identifies and eliminates outliers in the horizontal or vertical component *** is significant because common points in a continuous GNSS network may contain *** proposed approach is tested with the Géoazur GNSS network with the results showing that the Dikin estimator detects outliers at 6 out of 18 common points,among which three points are found with outliers in the vertical compo-nent ***,instead of eliminating all coordinate components of these six common points,we only eliminate all coordinate components of three common points and only the vertical component of another three common ***,the classical LS estimation is applied to“clean”data to estimate seven parameters of the Helmert transformation with a significant accuracy *** Dikin estimator’s results are compared to those of other robust estimators of Huber and Theil-Sen,which shows that the Dikin estimator performs ***,the weighted total least-squares estimation is implemented to assess the accuracy of the LS estimation with the same *** inter-comparison of the seven estimated parameters and their standard deviations shows a small difference at a few per million levels(E-6).

关键词： Continuous GNSS tectonic geodesy Dikin estimation Helmert transformation

Truly optimal semi-active damping to control free vibration of a single degree of freedom system

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Theoretical & Applied Mechanics Letters 2024年第2期14卷 142-145页

作者： Viet duc La Ngoc Tuan nguyen Institute of Mechanics Vietnam Academy of Science and TechnologyHanoi 10000Vietnam Graduate University of Science and Technology Vietnam Academy of Science and TechnologyHanoi 10000Vietnam

This paper studies a single degree of freedom system under free vibration and controlled by a general semiactive damping.A general integral of squared error is considered as the performance index.A one-time switching damping controller is proposed and *** pontryagin maximum principle is used to prove that no other form of semi-active damping can provide the better performance than the proposed one-time switching damping.

关键词： Analytical optimization Quadratic integral Lyapunov equation Pontryagin maximum principle

An analytical model for cross-Kerr nonlinearity in a four-level N-type atomic system with Doppler broadening

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Chinese Physics B 2022年第2期31卷 314-319页

作者： dinh Xuan Khoa nguyen Huy Bang nguyen Le Thuy An nguyen Van Phu Le Van Doai Vinh University 182 Le Duan StreetVinh CityVietna

We present an analytical model for cross-Kerr nonlinear coefficient in a four-level N-type atomic medium under Doppler *** model is applied to87 Rb atoms to analyze the dependence of the cross-Kerr nonlinear coefficient on the external light field and the temperature of atomic *** analysis shows that in the absence of electromagnetically induced transparency(EIT)the cross-Kerr nonlinear coefficient is zero,but it is significantly enhanced when the EIT is *** means that the cross-Kerr effect can be turned on/off when the external light field is on or ***,the amplitude and the sign of the cross-Kerr nonlinear coefficient are easily changed according to the intensity and frequency of the external light *** amplitude of the cross-Kerr nonlinear coefficient remarkably decreases when the temperature of atomic medium *** analytical model can be convenient to fit experimental observations and applied to photonic devices.

关键词： electromagnetically induced transparency Kerr nonlinear effect Doppler effect

Enhancing compressive strength and durability of self-compacting concrete modified with controlled-burnt sugarcane bagasse ash-blended cements

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Frontiers of Structural and Civil Engineering 2022年第2期16卷 161-174页

作者： duc-Hien LE Yeong-Nain SHEEN Khanh-Hung nguyen Sustainable Developments in Civil Engineering Research Group Faculty of Civil EngineeringTon Duc Thang UniversityHo Chi Minh City700000Vietnam Department of Civil Engineering Kaohsiung University of Science and TechnologyKaohsiung80778China Department of Civil Engineering Lac Hong UniversityBien Hoa810000Vietnam

In sugar industries,the growing amount of sugarcane bagasse ash(SBA),a byproduct released after burning bagasse for producing electricity,is currently causing environmental *** residual ash displays a pozzolanic potential;and hence,it has potential as a cement *** study focuses on enhancing suitability of SBA through incorporating ground blast furnace slag(BFS)in manufacturing self-compacting concretes(SCCs).For this purpose,SBA was processed by burning at 700°C for 1 h,before being ground to the cement fineness of 4010 cm2/*** mixtures were prepared by changing the proportions of SBA and BFS(i.e.,10%,20%,and 30%)in blended systems;and their performance was *** results showed that the presence of amorphous silica was detected for the processed SBA,revealing that the strength activity index was above 80%.The compressive strength of SCC containing SBA(without BFS)could reach 98%–127%of that of the control;combination of SBA and 30%BFS gets a similar strength to the control after 28 *** durability,the 10%SBA+30%BFS mix exhibited the lowest risk of ***,the joint use of SBA and BFS enhanced significantly the SCC’s sulfate ***,a hyperbolic formula for interpolating the compressive strength of the SBA-based SCC was proposed and validated with error range estimated within±10%.

关键词： sugarcane bagasse ash self-compacting concrete compressive strength sulfate resistance water absorption strength formula