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RESEARCH ON THE CONSTRUCTION OF A PHANTOM IN DOSE CALCULATION BY PHITS SIMULATION PROGRAM 用phits模拟程序构建剂量计算中虚影的研究
Journal of Science Natural Science Pub Date : 2022-06-01 DOI: 10.18173/2354-1059.2022-0022
Hung Bui Tien, Duong Tran Thuy, Ha Bui Ngoc, Thao Nguyen Thi
{"title":"RESEARCH ON THE CONSTRUCTION OF A PHANTOM IN DOSE CALCULATION BY PHITS SIMULATION PROGRAM","authors":"Hung Bui Tien, Duong Tran Thuy, Ha Bui Ngoc, Thao Nguyen Thi","doi":"10.18173/2354-1059.2022-0022","DOIUrl":"https://doi.org/10.18173/2354-1059.2022-0022","url":null,"abstract":"In the field of medical physics, determining the dosage for organs is a very complex problem because it is impossible to directly measure the dosage inside a living person's body. Therefore, in order to estimate the dosage, one usually has to use phantoms. For dosage determination and safety assessment, Monte Carlo simulation programs and today's phantoms have become indispensable tools. There are already several standard phantoms in the world but they do not represent biological characteristics by region or for a specific object. Another method used to build characteristic phantoms is done through computed tomography (CT) images and the Hounsfield index. The method requires to convert the grayscale value of each pixel element into the Hounsfield index. As such, it can only be applied to CT imaging. To overcome this shortcoming, this study has developed a program based on a new process that can convert images to geometric format for MCNPPHITS. The new procedure that we propose will allow researchers to describe the anatomical structures more accurately and be specific to each patient.","PeriodicalId":17007,"journal":{"name":"Journal of Science Natural Science","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89879437","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
GRADED VERSION OF EXEL’S EFFROS-HAHN CONJECTURE FOR LEAVITT PATH ALGEBRAS 关于leavitt路径代数的exel effros-hahn猜想的分级版本
Journal of Science Natural Science Pub Date : 2022-06-01 DOI: 10.18173/2354-1059.2022-0020
Loc Nguyen Quang, Ha Le Thi
{"title":"GRADED VERSION OF EXEL’S EFFROS-HAHN CONJECTURE FOR LEAVITT PATH ALGEBRAS","authors":"Loc Nguyen Quang, Ha Le Thi","doi":"10.18173/2354-1059.2022-0020","DOIUrl":"https://doi.org/10.18173/2354-1059.2022-0020","url":null,"abstract":"In this paper, we prove a graded version of Exel’s Effros-Hahn conjecture for Leavitt path algebras. More concretely, we show that any graded primitive ideal of the Leavitt path algebra is the annihilator of a module induced from a graded simple module over an isotropy group algebra. A graded version of Steinberg’s results towards Exel’s conjecture in (B. Steinberg, Ideals of etale ´groupoid algebras and Exel’s Effros-Hahn conjecture, J. Noncommut. Geom., Vol. 15, 2021, pp. 829-839) is also obtained for graded ample groupoid algebras.","PeriodicalId":17007,"journal":{"name":"Journal of Science Natural Science","volume":"8 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80883338","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: 1
SOME GEOMETRIC CHARACTERIZATIONS OF EXTREMAL SETS IN HILBERT SPACES Hilbert空间中极值集的一些几何特征
Journal of Science Natural Science Pub Date : 2022-06-01 DOI: 10.18173/2354-1059.2022-0019
Khiem Nguyen Van
{"title":"SOME GEOMETRIC CHARACTERIZATIONS OF EXTREMAL SETS IN HILBERT SPACES","authors":"Khiem Nguyen Van","doi":"10.18173/2354-1059.2022-0019","DOIUrl":"https://doi.org/10.18173/2354-1059.2022-0019","url":null,"abstract":"Based on our previous result and by using the technique on α-minimal and χ-minimal sets with respect to the Kuratowski and Hausdorff measures of noncompactness, we give some new geometric characterizations of extremal sets in Hilbert spaces.","PeriodicalId":17007,"journal":{"name":"Journal of Science Natural Science","volume":"359 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76420216","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
STRUCTURAL, FERROELECTRIC AND ELECTRICAL-FIELD-INDUCED PIEZOELECTRIC PROPERTIES OF PbTiO3-MODIFIED COMPLEX 0.5Ba(Zr0.2Ti0.8)O3-0.5(Ba0.7Ca0.3)TiO3 MATERIALS pbtio3修饰配合物0.5Ba(Zr0.2Ti0.8)O3-0.5(Ba0.7Ca0.3)TiO3材料的结构、铁电和电场致压电性能
Journal of Science Natural Science Pub Date : 2022-06-01 DOI: 10.18173/2354-1059.2022-0024
T. Nguyen Hoang, Duong Nguyen Xuan, Lam Nguyen Huu, Bac Luong Huu, Vinh Pham Van, Trung Nguyen Ngoc, Duc Nguyen Van, Dung Nguyen Duc
{"title":"STRUCTURAL, FERROELECTRIC AND ELECTRICAL-FIELD-INDUCED PIEZOELECTRIC PROPERTIES OF PbTiO3-MODIFIED COMPLEX 0.5Ba(Zr0.2Ti0.8)O3-0.5(Ba0.7Ca0.3)TiO3 MATERIALS","authors":"T. Nguyen Hoang, Duong Nguyen Xuan, Lam Nguyen Huu, Bac Luong Huu, Vinh Pham Van, Trung Nguyen Ngoc, Duc Nguyen Van, Dung Nguyen Duc","doi":"10.18173/2354-1059.2022-0024","DOIUrl":"https://doi.org/10.18173/2354-1059.2022-0024","url":null,"abstract":"Complex ferroelectric PbTiO3-modified 0.5Ba(Zr0.2Ti0.8)O3-0.5(Ba0.7Ca0.3)TiO3 materials were synthesized by a conventional solid-state reaction method. The addition of PbTiO3 into host 0.5Ba(Zr0.2Ti0.8)O3-0.5(Ba0.7Ca0.3)TiO3 materials are modified the ferroelectric properties of host materials where the maximum polarization slightly increased from 23.09 Ccm2 to 23.28 Ccm2 and the remnant polarization is found to increase from 10.07 Ccm2 to 11.31 Ccm2. The large piezoelectric dynamic coefficient value of 662 pmV is obtained for 7 mol. % PbTiO3 modified 0.5Ba(Zr0.2Ti0.8)O3-0.5(Ba0.7Ca0.3)TiO3 compounds as solid solution. Our work is expected to contribute to the role of A-site modification in lead-free ferroelectric BaTiO3-based materials for advanced function materials for electronic device applications.","PeriodicalId":17007,"journal":{"name":"Journal of Science Natural Science","volume":"58 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83377526","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
SCREENING YEAST FROM NATURAL HONEY, AND BEESWAX IN SON LA PROVINCE FOR LOW-ALCOHOL MEAD PRODUCTION 从山东省天然蜂蜜和蜂蜡中筛选酵母用于低酒精蜂蜜酒的生产
Journal of Science Natural Science Pub Date : 2022-06-01 DOI: 10.18173/2354-1059.2022-0031
Nam Nguyen Hoang, Thanh Phan Due, Thuy Tran Thi
{"title":"SCREENING YEAST FROM NATURAL HONEY, AND BEESWAX IN SON LA PROVINCE FOR LOW-ALCOHOL MEAD PRODUCTION","authors":"Nam Nguyen Hoang, Thanh Phan Due, Thuy Tran Thi","doi":"10.18173/2354-1059.2022-0031","DOIUrl":"https://doi.org/10.18173/2354-1059.2022-0031","url":null,"abstract":"Son La is a northern mountainous province of Vietnam, where the climate and soil are suitable for various flowering plants and for many honey bee species to grow and produce high-quality honey. Yeasts in honey are expected to have valuable characteristics that can be applied in many fields. In this paper, seventy-two yeast strains isolated from natural honey and beeswax in Son La were screened for the ability of alcoholic fermentation to produce mead. Screening yeast strains for lowalcohol mead production were carried out based on the fermentation ability and the sensory of the final mead product. Yeast train NT95 was selected and characterized as Zygosaccharomyces sp. NT95. A suitable condition for the growth of Zygosaccharomyces sp. NT95 was Hansen broth containing a sugar concentration of 60 - 90 gL at pH 4.0 - 4.5, and a temperature of 30 °C. A suitable condition for the alcoholic fermentation of Zygosaccharomyces sp. NT95 in the honey medium was at 30 °C with the inoculum of 5 x 107 cellsmL for 18 days. Under this condition, the mead produced by Zygosaccharomyces sp. NT95 contained approximately 4.5% alcohol (vv) and the sensory score reached 14.51 ± 0.15 points. Further studies need to be done to improve the fermentation process and the completion of the product.","PeriodicalId":17007,"journal":{"name":"Journal of Science Natural Science","volume":"30 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74291138","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
INVESTIGATION OF I-V CHARACTERISTICS OF CARBON NANOTUBES AND TIN OXIDE NANOWIRES HETEROJUNCTION FOR GAS SENSING APPLICATIONS 气敏用碳纳米管和氧化锡纳米线异质结的i-v特性研究
Journal of Science Natural Science Pub Date : 2022-06-01 DOI: 10.18173/2354-1059.2022-0026
Nguyet Quan Thi Minh, Hoa Tran Thi Ngoc, Duy Nguyen Van, H. Nguyen Duc, Hieu Nguyen Van
{"title":"INVESTIGATION OF I-V CHARACTERISTICS OF CARBON NANOTUBES AND TIN OXIDE NANOWIRES HETEROJUNCTION FOR GAS SENSING APPLICATIONS","authors":"Nguyet Quan Thi Minh, Hoa Tran Thi Ngoc, Duy Nguyen Van, H. Nguyen Duc, Hieu Nguyen Van","doi":"10.18173/2354-1059.2022-0026","DOIUrl":"https://doi.org/10.18173/2354-1059.2022-0026","url":null,"abstract":"In this study, heterojunctions of carbon nanotubes (CNTs) and tin oxide nanowires (SnO2) were investigated to determine their electrical performance for gas sensing applications. The I–V characteristics of the heterojunction were measured in air and H2S gas. The electrical parameters such as barrier height ϕB, ideality factor n, series resistance Rs, and reverse saturation current Io were extracted from the I-V plots. In H2S gas, the barrier height ϕB and series resistance Rs are lower compared to air, whereas the ideality factor n and saturation current Io are higher. These findings are essential for promoting technologies aimed at forming high-quality heterojunctions for gas sensing applications.","PeriodicalId":17007,"journal":{"name":"Journal of Science Natural Science","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90174896","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
PARTICULATE MATTER LEVELS AND ELEMENTAL COMPOSITION IN THE SPRING AND TRANSITION PERIOD IN HANOI, VIETNAM 越南河内市春季和过渡时期颗粒物水平和元素组成
Journal of Science Natural Science Pub Date : 2022-06-01 DOI: 10.18173/2354-1059.2022-0028
Manh Hoang Van, Thuy Ly Bich, Loc Nguyen Dac, T. Nguyen Minh, Anh Van Dieu, Giang Ton Thu, Hiền Nguyễn Thị Thu, Ha Vo Thi Le
{"title":"PARTICULATE MATTER LEVELS AND ELEMENTAL COMPOSITION IN THE SPRING AND TRANSITION PERIOD IN HANOI, VIETNAM","authors":"Manh Hoang Van, Thuy Ly Bich, Loc Nguyen Dac, T. Nguyen Minh, Anh Van Dieu, Giang Ton Thu, Hiền Nguyễn Thị Thu, Ha Vo Thi Le","doi":"10.18173/2354-1059.2022-0028","DOIUrl":"https://doi.org/10.18173/2354-1059.2022-0028","url":null,"abstract":"Particulate matter (PM) is a major environmental concern in Vietnam as well as in the world. Samples of PM2.5, PM10, and total suspended particle (TSP) were collected on the rooftop of a five-floor building inside Hanoi University of Science and Technology, Hanoi, from January to May 2015. The levels PM2,5, PM10, and the metal elements of TSP were determined. PM2,5 and PM10 had average concentrations of 73 ± 37 and 138 ± 67 μgm3, respectively. The concentration of PM2,5 and PM10 in all samples were higher than the recommended level in the World Health Organization (WHO) guideline (2005) for 24h and annual concentrations of 25 and 50 μgm3, respectively. Nineteen elements detected in TSP samples included the higher concentration group in order: Ca > Fe > Na > Al > Mg > K > Zn and in the lower concentration group: Pb > Mn > Ti > Sr > V > Cr > Cd. The potential sources revealed from element components were discussed.","PeriodicalId":17007,"journal":{"name":"Journal of Science Natural Science","volume":"90 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79504660","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 SEMILINEAR COUPLED SYSTEMS FOR THE EXTERNAL DAMPING MODELS WITH VARIABLE COEFFICIENTS 变系数外阻尼模型的半线性耦合系统
Journal of Science Natural Science Pub Date : 2022-06-01 DOI: 10.18173/2354-1059.2022-0018
Duong Pham Trieu
{"title":"THE SEMILINEAR COUPLED SYSTEMS FOR THE EXTERNAL DAMPING MODELS WITH VARIABLE COEFFICIENTS","authors":"Duong Pham Trieu","doi":"10.18173/2354-1059.2022-0018","DOIUrl":"https://doi.org/10.18173/2354-1059.2022-0018","url":null,"abstract":"We present in this article some results on the global solvability with arbitrarily small data of the Cauchy problem for the following semilinear coupled system with a variable coefficient utt + a(x)(−∆)σu + ut = F(|D|αv, vt), vtt + a(x)(−∆)σv + vt = G(|D|αu, ut), u(0, x) = u0(x), ut(0, x) = u1(x), v(0, x) = v0(x), vt(0, x) = v1(x). The nonlinearities are of the form (F, G) = (||D|αv|p, ||D|αu|q), or (F, G) = (|vt|p, |ut|q), and the parameter σ satisfies σ ∈ (0, 1). We will show that the ”critical exponents” p, q for the small data global solvability have a close relation to the established exponents of the corresponding semilinear problems for the external damping equations.","PeriodicalId":17007,"journal":{"name":"Journal of Science Natural Science","volume":"40 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74865318","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
PREDICTING ELASTIC MODULUS OF THE BODY-CENTERED CUBIC METALLIC FILMS 体心立方金属薄膜弹性模量的预测
Journal of Science Natural Science Pub Date : 2022-06-01 DOI: 10.18173/2354-1059.2022-0023
Phuong Duong Dai
{"title":"PREDICTING ELASTIC MODULUS OF THE BODY-CENTERED CUBIC METALLIC FILMS","authors":"Phuong Duong Dai","doi":"10.18173/2354-1059.2022-0023","DOIUrl":"https://doi.org/10.18173/2354-1059.2022-0023","url":null,"abstract":"The elastic modulus of the body-centered cubic (BCC) films is studied based on the moment method. For Fe, Ta, and W films a clear elastic modulus dependence of the thickness at ambient conditions and under temperatures up to 2000 K. The obtained results of the values of elastic modulus metallic films are smaller than the corresponding values of bulk material. Calculated results show the effects of temperature and thickness of elastic modulus for Fe, Ta, and W metallic films. On the other hand, when the thickness of thin films is about 60nm then the elastic modulus of the BCC films approaches the values of bulk material. Our results are compared with the other theoretical results and experimental values of bulk materials.","PeriodicalId":17007,"journal":{"name":"Journal of Science Natural Science","volume":"8 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89387670","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
ENHANCE A PHOTOCATALYTIC ACTIVITY ON Ag3PO4 BY AgAg3PO4 COMPOSITES AgAg3PO4复合材料增强Ag3PO4的光催化活性
Journal of Science Natural Science Pub Date : 2022-06-01 DOI: 10.18173/2354-1059.2022-0025
Hung Nguyen Manh, Than Dao Viet, Thuy Nguyen Thi Dieu, Anh Ho Quynh, Khang Nguyen Cao, Oanh Le Thi Mai, Chung Pham Do, Nhung Nguyen Thi, Hang Lam Thi
{"title":"ENHANCE A PHOTOCATALYTIC ACTIVITY ON Ag3PO4 BY AgAg3PO4 COMPOSITES","authors":"Hung Nguyen Manh, Than Dao Viet, Thuy Nguyen Thi Dieu, Anh Ho Quynh, Khang Nguyen Cao, Oanh Le Thi Mai, Chung Pham Do, Nhung Nguyen Thi, Hang Lam Thi","doi":"10.18173/2354-1059.2022-0025","DOIUrl":"https://doi.org/10.18173/2354-1059.2022-0025","url":null,"abstract":"In this study, we investigated the formation and influence of Ag particles on the physical properties and photocatalytic performance of Ag3PO4 photocatalysts when Ag particles adhered to the Ag3PO4 surface. The material is prepared by a simple precipitation method with illumination. The properties of the materials were investigated by X-ray diffraction (XRD), Raman scattering, scanning electron microscopy (SEM), UV-vis absorption, and the photocatalytic ability to decompose organic solutions. The results show the vibrational change of the [PO4] group in the structure presented in the Raman scattering spectrum highest RhB decomposition. The experimental results indicated that the AgAg3PO4 showed highly efficient and stable photocatalytic activity under visible light irradiation. The AgAg3PO4 sample with the Ag+PO43- the ratio of 3.61 gave efficiency when stimulated with visible light of Xenon lamps. This sample degraded almost completely to RhB in 10 ppm solution after 15 min of illumination, with a decomposition rate of 0.241 min-1.","PeriodicalId":17007,"journal":{"name":"Journal of Science Natural Science","volume":"37 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84815227","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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