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THE STUDY IN DIFFUSION MECHANISM BY VORONOI POLYHEDRON IN SODIUM TETRA-SILICATE MELT voronoi多面体在四硅酸钠熔体中的扩散机理研究
Journal of Science Natural Science Pub Date : 2021-10-01 DOI: 10.18173/2354-1059.2021-0046
Lich Duong Thi, San Luyen Thi, Yen Nguyen Hai
{"title":"THE STUDY IN DIFFUSION MECHANISM BY VORONOI POLYHEDRON IN SODIUM TETRA-SILICATE MELT","authors":"Lich Duong Thi, San Luyen Thi, Yen Nguyen Hai","doi":"10.18173/2354-1059.2021-0046","DOIUrl":"https://doi.org/10.18173/2354-1059.2021-0046","url":null,"abstract":"Molecular dynamic simulation is carried out for Sodium tetra-silicate (NS4) melt at 1873 K and pressure of 0.1 MPa. The diffusion mechanism of Na atoms is investigated in terms of Voronoi polyhedron around network former and displacement of Na atoms between them. The simulation shows that Na atoms are not uniformly distributed through polyhedrons, but they mainly gather in nonbridging oxygen (NBO) and free oxygen (FO) polyhedrons. More than 75.22% of total Na atoms are place in NBO polyhedrons, although the number of NBO polyhedrons is only 22.27%. The two motion types give mainly contribution to Na diffusion: hopping of isolated Na atom or collective displacement. During 150 ps, the system comprises two separate regions: Na-poor regions formed by Si-O subnets and Na-rich regions formed by O2 clusters. The two regions have strongly different chemical composition, the density of Na atoms as well as motion type of Na atoms.","PeriodicalId":17007,"journal":{"name":"Journal of Science Natural Science","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79953967","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
A NOTE ON GENERALIZED RAINBOW CONNECTION OF CONNECTED GRAPHS AND THEIR NUMBER OF EDGES 关于连通图的广义彩虹连接及其边数的一个注记
Journal of Science Natural Science Pub Date : 2021-10-01 DOI: 10.18173/2354-1059.2021-0041
Anh Nguyen Thi Thuy, Duyen Le Thi
{"title":"A NOTE ON GENERALIZED RAINBOW CONNECTION OF CONNECTED GRAPHS AND THEIR NUMBER OF EDGES","authors":"Anh Nguyen Thi Thuy, Duyen Le Thi","doi":"10.18173/2354-1059.2021-0041","DOIUrl":"https://doi.org/10.18173/2354-1059.2021-0041","url":null,"abstract":"Let l ≥ 1, k ≥ 1 be two integers. Given an edge-coloured connected graph G. A path P in the graph G is called l-rainbow path if each subpath of length at most l + 1 is rainbow. The graph G is called (k, l)-rainbow connected if any two vertices in G are connected by at least k pairwise internally vertex-disjoint l-rainbow paths. The smallest number of colours needed in order to make G (k, l)-rainbow connected is called the (k, l)-rainbow connection number of G and denoted by rck,l(G). In this paper, we first focus to improve the upper bound of the (1, l)-rainbow connection number depending on the size of connected graphs. Using this result, we characterize all connected graphs having the large (1, 2)-rainbow connection number. Moreover, we also determine the (1, l)-rainbow connection number in a connected graph G containing a sequence of cut-edges.","PeriodicalId":17007,"journal":{"name":"Journal of Science Natural Science","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72799415","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
THERMODYNAMIC PROPERTY OF ALLOY FCC-AuCuLi AT ZERO PRESSURE 零压下FCC-AuCuLi合金的热力学性质
Journal of Science Natural Science Pub Date : 2021-10-01 DOI: 10.18173/2354-1059.2021-0048
Hoc Nguyen Quang, Hien Nguyen Duc
{"title":"THERMODYNAMIC PROPERTY OF ALLOY FCC-AuCuLi AT ZERO PRESSURE","authors":"Hoc Nguyen Quang, Hien Nguyen Duc","doi":"10.18173/2354-1059.2021-0048","DOIUrl":"https://doi.org/10.18173/2354-1059.2021-0048","url":null,"abstract":"We briefly present the thermodynamic theory of FCC ternary substitutional and interstitial alloy at zero pressure derived by the statistical moment method and apply this theory to alloy AuCuLi. The thermodynamic properties of Au, AuCu and AuLi are specific cases for that of AuCuLi. We compare the thermodynamic properties of alloys AuCuSi and AuCuLi. Our calculated results of thermodynamic quantities for AuCuLi predict and orient experimental results in the future.","PeriodicalId":17007,"journal":{"name":"Journal of Science Natural Science","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73671497","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
AN IMPROVED DIJKSTRA ALGORITHM TO FIND MINIMUM TIME PATHS FOR BUS USERS IN HANOI 一种改进的dijkstra算法寻找河内市公交用户的最小时间路径
Journal of Science Natural Science Pub Date : 2021-10-01 DOI: 10.18173/2354-1059.2021-0049
Giang Vu Thai, Ngan Nguyen Thi Kim, Hoang Nguyen Ba, Duc Bui Minh
{"title":"AN IMPROVED DIJKSTRA ALGORITHM TO FIND MINIMUM TIME PATHS FOR BUS USERS IN HANOI","authors":"Giang Vu Thai, Ngan Nguyen Thi Kim, Hoang Nguyen Ba, Duc Bui Minh","doi":"10.18173/2354-1059.2021-0049","DOIUrl":"https://doi.org/10.18173/2354-1059.2021-0049","url":null,"abstract":"In Hanoi, many roads are congested during rush hour. When going through congested roads, the movement of vehicles is very slow. As a result, traveling over a short and congested road may take more time than traveling over a longer and uncongested road. Therefore, in this paper, we study the problem of finding optimal bus routes that take less time, considering the traffic jams. We extend Dijkstra's algorithm to compute waiting time at bus stations and traveling time of buses. The experimental results show that our algorithm is suitable.","PeriodicalId":17007,"journal":{"name":"Journal of Science Natural Science","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87794359","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
EQUILIBRIUM VACANCY CONCENTRATION AND THERMODYNAMIC QUANTITIES OF FCC DEFECTIVE ALLOYS AuCuSi AND PtCuSi UNDER PRESSURE AND TEMPERATURE FCC缺陷合金AuCuSi和PtCuSi在压力和温度下的平衡空位浓度和热力学量
Journal of Science Natural Science Pub Date : 2021-10-01 DOI: 10.18173/2354-1059.2021-0045
V. Le Hong, Hoc Nguyen Quang
{"title":"EQUILIBRIUM VACANCY CONCENTRATION AND THERMODYNAMIC QUANTITIES OF FCC DEFECTIVE ALLOYS AuCuSi AND PtCuSi UNDER PRESSURE AND TEMPERATURE","authors":"V. Le Hong, Hoc Nguyen Quang","doi":"10.18173/2354-1059.2021-0045","DOIUrl":"https://doi.org/10.18173/2354-1059.2021-0045","url":null,"abstract":"We present the analytic expressions of the cohesive energy, the alloy parameters, the equation of state, the mean nearest neighbor distance, the Helmholtz free energy, equilibrium vacancy concentration, and thermodynamic quantities such as the isothermal compressibility, the thermal expansion coefficient, the heat capacities at constant volume and constant pressure for facecentered cubic (FCC) defective ternary substitutional and interstitial alloy ABC derived by the statistical moment method (SMM). The obtained thermodynamic quantities depend on temperature, pressure, the concentration of substitutional atoms, the concentration of interstitial atoms, and equilibrium vacancy concentration. Thermodynamic quantities of FCC defective metal A, FCC defective substitutional alloy AB, and FCC defective interstitial alloy AC are specific cases for thermodynamic quantities of FCC defective ternary substitutional and interstitial alloy ABC. The theoretical results are calculated numerically to alloys AuCuSi and PtCuSi. Our calculated results of thermal expansion coefficient and heat capacities at constant pressure for main metals Au, Pt are in good agreement with experimental data. Our other calculated results for thermodynamic quantities of alloys AuCuSi and PtCuSi at different temperatures, pressure, the concentration of substitutional atoms, and concentrations of interstitial atoms orient and predict new experimental data in the future.","PeriodicalId":17007,"journal":{"name":"Journal of Science Natural Science","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82014786","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
STABILITY OF A MATHEMATICAL MODEL DESCRIBING THE COVID-19 PANDEMIC IN TERMS OF THE ENVIRONMENT, SOCIAL DISTANCING AND REINFECTION 从环境、社交距离和再感染的角度描述COVID-19大流行的数学模型的稳定性
Journal of Science Natural Science Pub Date : 2021-10-01 DOI: 10.18173/2354-1059.2021-0042
Nhu Luong Ngoc, Huyen Lai Thi Ngoc, Giang Vu Thi Huong, Hang Pham Thi
{"title":"STABILITY OF A MATHEMATICAL MODEL DESCRIBING THE COVID-19 PANDEMIC IN TERMS OF THE ENVIRONMENT, SOCIAL DISTANCING AND REINFECTION","authors":"Nhu Luong Ngoc, Huyen Lai Thi Ngoc, Giang Vu Thi Huong, Hang Pham Thi","doi":"10.18173/2354-1059.2021-0042","DOIUrl":"https://doi.org/10.18173/2354-1059.2021-0042","url":null,"abstract":"In this paper, we propose and study the stability of a mathematical model for the Covid-19 pandemic incorporating the environment, social distancing and reinfection. A numerical example is carried out to consider the obtained results.","PeriodicalId":17007,"journal":{"name":"Journal of Science Natural Science","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75127386","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
MAPPING MULTI-SCALED LANDSCAPE TYPOLOGY OF LANG SON PROVINCE 谅山省多尺度景观类型学制图
Journal of Science Natural Science Pub Date : 2021-10-01 DOI: 10.18173/2354-1059.2021-0061
Dung Bui Thi Thanh
{"title":"MAPPING MULTI-SCALED LANDSCAPE TYPOLOGY OF LANG SON PROVINCE","authors":"Dung Bui Thi Thanh","doi":"10.18173/2354-1059.2021-0061","DOIUrl":"https://doi.org/10.18173/2354-1059.2021-0061","url":null,"abstract":"The landscape of a territory is generated by natural components, and it is also influenced by human activities. The complexity of factors making up landscape and the relationship between them with humans has created a diverse and complex differentiation of landscape in Lang Son province. Three factors reflecting typical characteristics of Lang Son landscape: Digital Elevation Model (DEM), soil, and land cover have been selected in this study. The concept of multiscaled landscape classification based on the European Landscape Convention (ELC) is applied for combining the holistic with parametric approaches and combining typological with multi-scaled landscape classifications. A number of possible combinations between 9 land cover variables, 9 soil combination variables, and 5 topographic variables have yielded 40 landscape units for Lang Son province. The obtained results are basic documents for contributing to modern and practical landscape research on the one hand, and to territory planning for sustainable development of Lang Son on the other hand.","PeriodicalId":17007,"journal":{"name":"Journal of Science Natural Science","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91122918","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
THE e e Z l l bb + − − + → →  COLLISION IN THE RANDALL-SUNDRUM MODEL RANDALL-SUNDRUM模型中的e - Z - l - bb +−−+→→→<s:1>碰撞
Journal of Science Natural Science Pub Date : 2021-10-01 DOI: 10.18173/2354-1059.2021-0047
Giang Bui Thi Ha
{"title":"THE e e Z l l bb + − − + → →  COLLISION IN THE RANDALL-SUNDRUM MODEL","authors":"Giang Bui Thi Ha","doi":"10.18173/2354-1059.2021-0047","DOIUrl":"https://doi.org/10.18173/2354-1059.2021-0047","url":null,"abstract":"Taking account of the Randall-Sundrum model, we have evaluated the influence of model parameters in e e Z l l bb + − − + → →  collision at International Linear Colliders (ILC). In the ILC region, the total cross-section is enhanced at the 125 GeV radion. The total cross-section depends on the polarization of e e − + , initial beams, the radion mass m , the center of mass energy s . Based on the forward - backward asymmetry and the polarization of beams, the reaction can give observable cross-sections based on l l bb − + final state.","PeriodicalId":17007,"journal":{"name":"Journal of Science Natural Science","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74071871","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
VIETNAMESE Phellinus baumii FRUITING BODY, A POTENTIAL SOURCE OF ANTIOXIDANT AND α-AMYLASE INHIBITORY AGENTS 越南黄柏子实体:抗氧化剂和α-淀粉酶抑制剂的潜在来源
Journal of Science Natural Science Pub Date : 2021-10-01 DOI: 10.18173/2354-1059.2021-0054
Thuy Mai Phuong, Hong Do Thi, Mai Le Thi Tuyet, Hoa Le Thi Phuong
{"title":"VIETNAMESE Phellinus baumii FRUITING BODY, A POTENTIAL SOURCE OF ANTIOXIDANT AND α-AMYLASE INHIBITORY AGENTS","authors":"Thuy Mai Phuong, Hong Do Thi, Mai Le Thi Tuyet, Hoa Le Thi Phuong","doi":"10.18173/2354-1059.2021-0054","DOIUrl":"https://doi.org/10.18173/2354-1059.2021-0054","url":null,"abstract":"n-Hexane, ethyl acetate, and butanol fractions from methanol extract of Vietnamese Phellinus baumii fruiting body consisted of phenolics, flavonoids, and terpenoids. Ethyl acetate and butanol fractions showed a high level of total phenolics. Ethyl acetate fractions possessed the highest phenolic content (532.96 ± 19.95 mg GAEg), accounting for approximately 53% fraction dry weight. Free radical DPPH (1,1-diphenyl-2-picrylhydrazyl) scavenging capacity of all fractions correlated with their total phenolic content. Ethyl acetate fraction exhibited the strongest capacity with an IC50 value of 0.059 mgmL, equivalent to nearly 50% of ascorbic acid’s capacity. Its ferric reducing power was off more than half of quercetin and acid ascorbic at the concentration of 0.2 mgmL. Ethyl acetate also had remarkable α-amylase inhibitory activity (IC50= 0.38 mgmL). The results suggested P. baumii fruiting body as a potent source for antioxidative and α-amylase inhibitory compounds.","PeriodicalId":17007,"journal":{"name":"Journal of Science Natural Science","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84221890","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
ASSESSMENT OF THE USE OF DRUG TREATMENT OF DYSLIPIDEMIA AT MILITARY HOSPITAL 105 军队医院血脂异常患者用药评价[j]
Journal of Science Natural Science Pub Date : 2021-10-01 DOI: 10.18173/2354-1059.2021-0052
Tram Vu Thi, Trang Tran Thi Thu, Cong Vu Thanh, Phu Tran Doan, Binh Tran Quoc, Tuan Truong Quoc, L. Nguyen Ngoc
{"title":"ASSESSMENT OF THE USE OF DRUG TREATMENT OF DYSLIPIDEMIA AT MILITARY HOSPITAL 105","authors":"Tram Vu Thi, Trang Tran Thi Thu, Cong Vu Thanh, Phu Tran Doan, Binh Tran Quoc, Tuan Truong Quoc, L. Nguyen Ngoc","doi":"10.18173/2354-1059.2021-0052","DOIUrl":"https://doi.org/10.18173/2354-1059.2021-0052","url":null,"abstract":"Dyslipidemia characteristics of outpatients with dyslipidemia for the first time, characteristics of drug use, and effectiveness in controlling dyslipidemia indexes after 3 months of treatment at Military Hospital 105 were studied. A crosssectional, retrospective descriptive study was investigated on adult outpatients who were diagnosed with dyslipidemia for the first time, examined and treated as outpatients at the hospital, and monitored for effectiveness in blood lipid control for 3 months after starting treatment. The decision to use the drug at the start of the study and the achievement of treatment goals at the time points were analyzed based on the ESCEAS 2019 guidelines for treating DL. The majority of patients were aged > 45 years (80.5%), the most common group of patients was aged 46 - 59 (43.7%). The number of patients with comorbidities accounted for 62.8%. 87% of patients had mixed dyslipidemia, 54.8% of patients were in the group with high and very high cardiovascular risk. 93.5% of patients needed to start treatment with drugs based on LDL-C index at the time of treatment initiation. The majority of patients used monotherapy regimens, in which, Statins were used the most in the study sample with the rate of 95.3% in the initial treatment regimen. 70.4% of patients had an inappropriate decision to initiate treatment, of which the most common was the decision to use statins with insufficient dosage in patients (45.1%). Only 28% of patients reached their LDL-C goal after 3 months of treatment. From the high percentage of patients who did not reach the treatment goal in the study sample, it is necessary to consider using stronger statin therapy, higher dose statin, or using another treatment regimen for patients.","PeriodicalId":17007,"journal":{"name":"Journal of Science Natural Science","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76955342","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
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