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Novel Time Series Bagging Based Hybrid Models for Predicting Historical Water Levels in the Mekong Delta Region, Vietnam

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Computer Modeling in Engineering & Sciences 2022年第6期131卷 1431-1449页

作者： nguyen Thanh Hoan nguyen Van Dung Ho Le Thu Hoa Thuy Quynh Nadhir Al-Ansari Tran Van Phong Phan Trong Trinh Dam Duc nguyen Hiep Van Le hanh bich thi nguyen Mahdis Amiri Indra Prakash Binh Thai Pham Institute of Geography Vietnam Academy of Science and TechnologyHanoi10000Viet Nam Department of Civil Environmental and Natural Resources EngineeringLulea University of TechnologyLulea97187Sweden Institute of Geological Sciences Vietnam Academy of Science and Technology(VAST)Dong DaHanoi10000Viet Nam University of Transport Technology Thanh XuanHa Noi10000Viet Nam Department of Watershed&Arid Zone Management Gorgan University of Agricultural Sciences&Natural ResourcesGorgan***Iran DDG(R)Geological Survey of India Gandhinagar382010India

Water level predictions in the river,lake and delta play an important role in flood *** year Mekong River delta of Vietnam is experiencing flood due to heavy monsoon rains and high *** subsidence may also aggravate flooding problems in this ***,accurate predictions of water levels in this region are very important to forewarn the people and authorities for taking timely adequate remedial measures to prevent losses of life and *** are so many methods available to predict the water levels based on historical data but nowadays Machine Learning(ML)methods are considered the best tool for accurate *** this study,we have used surface water level data of 18 water level measurement stations of the Mekong River delta from 2000 to 2018 to build novel time-series Bagging based hybrid ML models namely:Bagging(RF),Bagging(SOM)and Bagging(M5P)to predict historical water levels in the study *** of the Bagging-based hybrid models were compared with Reduced Error Pruning Trees(REPT),which is a benchmark ML *** data of 19 years period was divided into 70:30 ratio for the *** data of the period 1/2000 to 5/2013(which is about 70%of total data)was used for the training and for the period 5/2013 to 12/2018(which is about 30%of total data)was used for testing(validating)the *** of the models was evaluated using standard statistical measures:Coefficient of Determination(R2),Root Mean Square Error(RMSE)and Mean Absolute Error(MAE).Results show that the performance of all the developed models is good(R2>0.9)for the prediction of water levels in the study ***,the Bagging-based hybrid models are slightly better than another model such as ***,these Bagging-based hybrid time series models can be used for predicting water levels at Mekong data.

关键词： Computational techniques bagging water level time series algorithms

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Comparative Chemical Research in Essential Oils from Six Apiaceae Species Growing in the Northern Region of Vietnam

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Phyton-International Journal of Experimental Botany 2024年第7期93卷 1677-1687页

作者： nguyen Quang Hung nguyen Thanh Tung nguyen Phuong hanh Chu thi Thu Ha nguyen thi Nhung nguyen Thai An Vu Xuan Giang Luong Van Hao Oleh Koshovyi Ain Raal Institute of Ecology and Biological Resources Vietnam Academy of Science and Technology(VAST)Cau GiayHa Noi100000Viet Nam Graduate University of Science and Technology Vietnam Academy of Science and Technology(VAST)Cau GiayHa Noi100000Viet Nam Department of Pharmacognosy Faculty of Pharmacognosy and Traditional MedicineHanoi University of PharmacyHoan KiemHa Noi100000Viet Nam Sa Pa Research Center of Medicinal Materials National Institute of Medicinal MaterialsDien Bien PhuSa PaLao Cai330000Viet Nam Institute of Pharmacy Faculty of MedicineUniversity of TartuTartu50411Estonia

Our study aimed to compare the essential oil(EO)concentration and composition of several Apiaceae species growing in the Northern region of *** yields of EOs from materials ranged from 0.03%(root EO of Angelica acutiloba and aerial parts EO of Heracleum bivittatum)-0.27%(leaf EO of Xyloselinum vietnamense).Gas chromatography-mass spectrometry(GC-MS)allowed the identiﬁcation of 74 components in the EOs of six Apiaceae species,making up 94.4%–100.0%of the *** EO from Angelica acutiloba,(Z)-ligustilide accounted for an extremely large proportion(94.9%).EO of Angelica pubescens was dominated by six character-istic components includingα-pinene(21.5%),β-phellandrene(18.1%),p-cymene(12.2%),3-methylnonane(8.7%),o-cymene(8.1%),and D-sylvestrene(6.2%).The EO from Cryptotaenia japonica was characterized by high amounts ofα-selinene(48.7%),β-selinene(23.7%),and trans-β-farnesene(5.4%).The EOs from leaves and stems of Xyloselinum vietnamense were characterized by high concentrations of sabinene(69.8%and 33.8%),4-terpineol(8.7%and 7.4%)andβ-pinene(4.0%and 6.5%)while EOs from aerial parts and root of Xylo-selinum leonidii comprise four characteristic monoterpenes includingα-pinene(28.2%and 52.8%),β-pinene(7.9%and 10.3%),β-phellandrene(7.6%and 15.3%),and sabinene(3.0%and 4.1%).Additionally,cryptone is also one of the major components in the EO of Xyloselinum leonidii(13.2%in the aerial parts oil and 2.8%in the root oil).In the EOs isolated from the aerial parts and root of Heracleum bivittatum,α-pinene(22.5%and 70.2%)andβ-pinene(43.2%and 20.0%)were the predominant *** appeared in the EO from aerial parts of Heracleum bivittatum with a relatively high concentration(13.5%)while bornyl acetate(5.1%)was also one of the main components in the EO from its aerial parts but was not detected in other Apiaceae species in the present *** databases help identify and control the quality of plant material studied from the family Apiaceae growing in Vietnam.

关键词： Apiaceae essential oil terpenoids gaschromatography-mass spectrometry

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Nickel composite plating with fly ash as inert particle

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Transactions of Nonferrous Metals Society of China 2013年第8期23卷 2348-2353页

作者： Viet Hue nguyen thi Anh Tuyet NGO Hong hanh PHAM Ngoc Phong nguyen Institute of Materials Science

The Ni/FA composite plating was realized by electrodeposition with fly ash （FA） as inert particles. The main compositions of FA are 72% SiO2 and 25% A1203 in the size of 3-7 Ixm. Electrodeposition was performed in Watts bath containing FA with concentrations of 5, 20, 50 g/L, current densities of 2 and 4 A/dm2, temperature of 50 ~C and magnetic stirring of 250 r/min. Scanning electron microscope （SEM＋EDX）, electrochemical and mechanical technique were used to study morphology, composition and properties of coating. FA content in deposit is dependent on the FA concentration in solution, as well as the plating parameters. Since FA particles were incorporated in the coating, the mechanical and electrochemical properties of the coating were increased. The microhardness of Ni/FA composite plating reaches HV 430 in comparison with HV 198 of pure Ni coating. It was confirmed by electrochemical measurement that the corrosion resistance of Ni/FA composite coating was higher than that of pure Ni.

关键词： composite plating fly ash microhardness corrosion resistance inert particles

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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

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Graphical method based on modified maximum force criterion to indicate forming limit curves of 22MnB5 boron steel sheets at elevated temperatures

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Journal of Iron and Steel Research International 2021年第8期28卷 1009-1018页

作者： Thanh Luyen Quoc-Tuan Pham thi-bich Mac Tien-Long Banh Duc-Toan nguyen Faculty of Mechanical Engineering Hungyen University of Technology and EducationHungyen 160000Vietnam Division of Computational Mathematics and Engineering Institute for Computational ScienceTon Duc Thang UniversityHo Chi Minh City 70000Vietnam Faculty of Civil Engineering Ton Duc Thang UniversityHo Chi Minh City 70000Vietnam School of Mechanical Engineering Hanoi University of Science and TechnologyHanoi City 100000Vietnam

A new approach for predicting forming limit curves(FLCs)at elevated temperatures was proposed *** are often used to predict failure and determine the optimal forming parameters of automotive ***,a graphical method based on a modified maximum force criterion was applied to estimate the FLCs of 22MnB5 boron steel sheets at room temperature using various hardening ***,the predicted FLC data at room temperature were compared with corresponding data obtained from Nakazima's tests to obtain the best *** estimate the FLC at elevated temperatures,tensile tests were conducted at various temperatures to determine the ratios of equivalent fracture strains between the corresponding elevated temperatures and room *** at elevated temperatures could be established based on obtained ***,the predicted FLCs at elevated temperatures did not agree well with the corresponding FLC experimental data of Zhou et al.A new method was proposed herein to improve the prediction of FLCs at elevated *** FLC calculated at room tem-perature was utilized to predict the failure of Nakazima's samples via finite element *** on the simulation results at room temperature,the mathematical relationships between the equivalent ductile fracture strain versus stress triaxiality and strain ratio were established and then combined with ratios between elevated and room temperatures to calculate the FLCs at different *** predicted FLCs at elevated temperatures agree well with the corresponding experimental FLC data.

关键词： Forming limit curve Modified maximum force criterion Graphical method Hardening law Finite element method Boron steel sheet Elevated temperature

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Controlling various contaminants in wastewater effluent through membranes and engineered wetland

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Frontiers of Environmental Science & Engineering 2009年第1期3卷 98-105页

作者： Sarper SARP Sungyun LEE Noeon PARK nguyen thi hanh Jaeweon CHO Department of Environmental Science and Engineering Gwangju Institute of Science and Technology(GIST)Gwangju 500-712Korea

For effective wastewater reclamation and water recovery,the treatment of natural and effluent organic matters(NOM and EfOM),toxic anions,and micropollutants was considered in this *** different NOM(humic acid of the Suwannee River,and NOM of US and Youngsan River,Korea),and one EfOM from the Damyang wastewater treatment plant,Korea,were selected for investigating the removal efficiencies of tight nanofiltration(NF)and ultrafiltration(UF)membranes with different ***,bromate,and perchlorate were selected as target toxic anions due to their well known high ***-(2-chloroethyl)-phosphate(TCEP),oxybenzone,and caffeine,due to their different K_(ow) and pK_(a) values,were selected as target *** expected,the NF membranes provided high removal efficiencies in terms of all the tested contaminants,and the UF membrane provided fairly high removal efficiencies for anions(except for nitrate)and the relatively hydrophobic micropollutant,*** the wetlands,nitrate was successfully ***,a fair process of combining membranes with an engineered wetland could be proposed for sustainable wastewater reclamation and optimum control of contaminats.

关键词： wastewater reclamation natural organic matter(NOM) effluent organic matter(EfOM) membranes wetlands

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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

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Optimization, equilibrium, adsorption behavior and role of surface functional groups on graphene oxide-based nanocomposite towards diclofenac drug

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Journal of Environmental Sciences 2020年第7期32卷 137-150页

作者： Thuan Van Tran Duyen thi Cam nguyen hanh TNLe Dai-Viet NVo Sonil Nanda Trinh Duy nguyen nguyen Tat Thanh Hi-Tech Institute Nguyen Tat Thanh UniversityHo Chi Minh City 755414Viet Nam Center of Excellence for Green Energy and Environmental Nanomaterials(CE@GrEEN) Nguyen Tat Thanh UniversityHo Chi Minh City 755414Viet Nam Institute of Hygiene and Public Health Ho Chi Minh City 700000Viet Nam Department of Chemical and Biochemical Engineering University of Western OntarioLondonOntarioCanada

Aquatic contamination of diclofenac(DCF),an emergent non-steroidal anti-inflammatory drug(NSAIDs),can result in adverse effects to many ecosystems through ***,introducing effective remediation techniques to sequester the pharmaceutical wastes is highly fundamental to prevent their accumulation in the ***,adsorption has been presented as a green and efficient ***,we report the characterization and application of the novel magnetic nanocomposite(GO@CoFe2O4)derived from cobalt-based ferrite(CoFe2O4)and graphene oxide(GO)for DCF *** the optimization procedure,the response surface methodology(RSM)was adopted to investigate the impacts of DCF concentration(1.6-18.4 mg/L),DCF dosage(0.08-0.92 g/L),and solution pH(2.6-9.4)to find the optimum conditions for DCF removal,at 10.5 mg/L,0.74 g/L,and pH 4,*** the adsorption experiments,the kinetic,isotherm,thermodynamic,and intraparticle diffusion models were systematically ***,we have elucidated the role of functional groups on the surface of GO@CoFe2O4 in enhancing the adsorption of DCF *** good removal efficiency(up to 86.1%),high maximum adsorption capacity(32.4 mg/g),GO@CoFe2O4 can be a potential candidate to eliminate DCF drug from water.

关键词： Diclofenac sodium Graphene oxide Magnetic nanocomposite Response surface methodology Pharmaceuticals adsorption

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Investigation of Polymorphisms in Coding Region of OsHKT1in Relation to Salinity in Rice

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Rice science 2016年第6期23卷 334-338页

作者： pham quynh-hoa tran xuan-an nguyen thi-nha-trang tran thi-thuy-anh hoang hai-yen nguyen thi-hong-van tang thi-hanh do thi-phuc Faculty of Biology VNU University of ScienceHanoi334 Nguyen TraiThanh XuanHanoiVietnam Faculty of Agronomy Vietnam National University of AgricultureNgo Xuan Quang StreetTrau QuyGia LamHanoiVietnam

Rice （Oryza sativa） is sensitive to salinity, but the salt tolerance level differs among cultivars,which might result from natural variations in the genes that are responsible for salt tolerance. High-affinitypotassium transporter （HKTs） has been proven to be involved in salt tolerance in plants. Therefore, wescreened for natural nucleotide polymorphism in the coding sequence of OsHKT1, which encodes the HKTprotein in eight Vietnamese rice cultivars differing in salt tolerance level. In total, seven nucleotidesubstitutions in coding sequence of OsHKT1 were found, including two non-synonymous and five synonymoussubstitutions. Further analysis revealed that these two non-synonymous nucleotide substitutions （G50Tand T1209A） caused changes in amino acids （Gly17Val and Asp403Glu） at signal peptide and the loop ofthe sixth transmembrane domain, respectively. To assess the potential effect of these substitutions on theprotein function, the 3D structure of HKT protein variants was modelled by using PHYRE2 webserver. Theresults showed that no difference was observed when compared those predicted 3D structure of HKTprotein variants with each other. In addition, the codon bias of synonymous substitutions cannot clearlyshow correlation with salt tolerance level. It might be interesting to further investigate the functional roles ofdetected non-synonymous substitutions as it might correlate to salt tolerance in rice.

关键词： polymorphism salt stress OsHKT1 gene rice

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Anti-inflammatory effects of fatty acids isolated from Chromolaena odorata

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Asian Pacific Journal of Tropical Medicine 2011年第10期4卷 760-763页

作者： Tran thi Hong hanh Dan thi Thuy Hang Chau Van Minh nguyen Tien Dat Institute of Marine Biochemistry Vietnam Academy of Science and Technology(VAST)

Objective:To identify inhibitors of nitric oxide production and NF-κB activity from Chromolaena odorata（***）.Methods:The compounds isolated from the aerial parts of *** by bioassay-guided fractionation were investigated for their inhibitory effects on the NO production and NF-κB activity in LPS-stimulated RAW264.7 ***:Six fatty acids （S）-coriolic acid（1）,（S）-coriolic acid methyl ester（2）,（5）-15,16-didehydrocoriolic acid（3）,（S）- 15,16-didehydrocoriolic acid methyl ester（4）,linoleamide（5） and linolenamide（6） were isolated. All compounds inhibited the NO production at concentrations consistent with those required for NF-κB *** 2 was the most active with the IC50 values of 5.22 and 5.73μM. The addition of a double bond in the fatty chain decreased the inhibitory effects while the methyl esterification increased the ***:The fatty acid components in *** with NF-κB inhibitory activity could explain the anti-inflammation property of this plant in traditional *** study could also contribute to the better use of *** for human health care.

关键词： Chromolaena odorata Asteraceae Fatty acid NF-κB Nitric oxide

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