核科学与技术国际期刊(英文)最新文献_第8页

Sub-Criticality Measurement with Source Term for Research Reactor in Inverse Kinetics Method 用逆动力学方法测量研究堆的源项亚临界度

核科学与技术国际期刊(英文) Pub Date : 2017-06-15 DOI: 10.4236/WJNST.2017.73011

N. Jahan, M. Rahman, M. Q. Huda, S. M. Seo

{"title":"Sub-Criticality Measurement with Source Term for Research Reactor in Inverse Kinetics Method","authors":"N. Jahan, M. Rahman, M. Q. Huda, S. M. Seo","doi":"10.4236/WJNST.2017.73011","DOIUrl":"https://doi.org/10.4236/WJNST.2017.73011","url":null,"abstract":"In reactor physics tests, it is important to monitor sub-criticality continuously during criticality approach. Reactivity measurements by the inverse kinetics method are widely used during the operation of a nuclear reactor. This technique is successfully applied at sufficiently high power level or to a core without an external neutron source where the neutron source term in point reactor kinetics equations may be neglected. For operation at low power levels or in the sub-critical domain, the increase in the fluctuation of the neutron signal may cause difficulties in the evaluation of reactivity and the effect of direct emission from the external neutron source may not be neglected. Therefore, contribution of the neutron source must be taken into account and this implies knowledge of a quantity proportional to the source strength, which calls the source term and then it should be determined. The research work has been conducted to measure reactivity with source term using a dedicated reactivity measurement system by the Least Square Inverse Kinetics Method (LSIKM). Application to a simulator of HANARO research reactor, Korea Atomic Energy Research Institute (KAERI), with known source strength and reactivity worth has showed consistent and satisfactory agreement.","PeriodicalId":61566,"journal":{"name":"核科学与技术国际期刊(英文)","volume":"07 1","pages":"129-135"},"PeriodicalIF":0.0,"publicationDate":"2017-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48930499","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

Determination of Uranium Traces in Nuclear Reactor IEA-R1 Pool Water 核反应堆iaea - r1池水中痕量铀的测定

核科学与技术国际期刊(英文) Pub Date : 2017-06-15 DOI: 10.4236/WJNST.2017.73014

A. M. Saliba-Silva, O. D. Santos, E. U. Carvalho, H. Riella, M. Durazzo

引用次数: 3

Response of COX2/PGE2 Inflammatory Pathway to Brown Seaweed Extract in Rats Exposed to Gamma Radiation COX2/PGE2炎症通路对γ射线照射大鼠褐藻提取物的反应

核科学与技术国际期刊(英文) Pub Date : 2017-06-15 DOI: 10.4236/WJNST.2017.73016

K. Azab, N. Meky, Eglal A. M. El-Deghidy, Ghada Azoz

{"title":"Response of COX2/PGE2 Inflammatory Pathway to Brown Seaweed Extract in Rats Exposed to Gamma Radiation","authors":"K. Azab, N. Meky, Eglal A. M. El-Deghidy, Ghada Azoz","doi":"10.4236/WJNST.2017.73016","DOIUrl":"https://doi.org/10.4236/WJNST.2017.73016","url":null,"abstract":"Background: Systemic inflammation due to radiation exposure has been identified in a biological system by certain metabolic and behavioral disorders. These anarchies mostly mediated under a regulation of cyclooxygenase 2 (COX2) induced production of an inflammatory mediator prostaglandin E2 (PGE2). Aim: This study was undertaken to investigate the anti-inflammatory impact of brown sea weed extract (BSWE) against induction of COX2/PGE2 inflammatory pathway in gamma-irradiated rats. Rats were orally administrated with BSWE (27 mg/kg body weight/day) for 7 consecutive days before exposure to 8 Gy fractionated gamma radiation (2 Gy × 4; every 3 days). Treatment with BSWE was extended along with and in-between irradiation doses for another 14 successive days. Our data demonstrated that the administration of BSWE to rats exposed to gamma radiation, following the regimen suggested, significantly neutralize the changes induced in the inflammatory molecules COX2, PGE2, tumor necrosis alpha (TNF-α), and nitric oxide (NO). In addition, it adjusted significantly the cellular redox tone via regulation of changes induced in malondialdehyde (MDA) reduced glutathione (GSH), superoxide dismutase (SOD) catalase (CAT) and xanthine oxidoreductase system (XOR). Credibly, from the results emerged in this study, it could be suggested that BSWE has substantial anti-inflammatory activities and gamma radiation protection capabilities. It is recommended to include BSWE in the treatment strategy of various inflammatory diseases especially cancer as a safe natural anti-inflammatory agent.","PeriodicalId":61566,"journal":{"name":"核科学与技术国际期刊(英文)","volume":"7 1","pages":"189-205"},"PeriodicalIF":0.0,"publicationDate":"2017-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46716760","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: 6

Geometric Models of Atomic Nuclei 原子核的几何模型

核科学与技术国际期刊(英文) Pub Date : 2017-06-15 DOI: 10.4236/WJNST.2017.73017

G. Bihari

引用次数: 1

The role of nuclear power from a system engineering standpoint 从系统工程的角度来看核能的作用

核科学与技术国际期刊(英文) Pub Date : 2017-06-15 DOI: 10.4236/WJNST.2017.73015

L. O. Freire, D. A. Andrade

引用次数: 5

Gamma Radiation Measurements of Naturally Occurring Radioactive in Igneous Rocks and Its Radiological Complications 火成岩中天然放射性物质的伽马辐射测量及其放射并发症

核科学与技术国际期刊(英文) Pub Date : 2017-06-15 DOI: 10.4236/WJNST.2017.73012

J. Al-Zahrani

引用次数: 4

Neutron Flux Signal Acquisition from Plant Instrumentation Channel of Research Reactor for Reactivity Calculation 用于反应性计算的研究堆装置仪表通道中子通量信号采集

核科学与技术国际期刊(英文) Pub Date : 2017-06-15 DOI: 10.4236/WJNST.2017.73013

N. Jahan, M. Rahman, M. Q. Huda

引用次数: 1

Coupling a Gas Chromatography Unit to an Inductively Coupled Plasma Mass Spectrometer 气相色谱装置与电感耦合等离子体质谱仪的耦合

核科学与技术国际期刊(英文) Pub Date : 2017-04-03 DOI: 10.4236/WJNST.2017.72007

Jerrad P. Auxier, J. Auxier, H. Hall

{"title":"Coupling a Gas Chromatography Unit to an Inductively Coupled Plasma Mass Spectrometer","authors":"Jerrad P. Auxier, J. Auxier, H. Hall","doi":"10.4236/WJNST.2017.72007","DOIUrl":"https://doi.org/10.4236/WJNST.2017.72007","url":null,"abstract":"Although the eminent threat of a terrorist group detonating an improvised nuclear device (IND) in an urban environment is low, it is crucial that countries develop modern nuclear forensic capabilities to expedite response in a post-detonation scenario. In particular, new instruments need to be created to shorten dissolution time, expedite chemical separation, and improve forensic analysis of the nuclear melt glass that is created during the detonation of the device. To expedite this process, an instrument was designed to thermally couple a gas chromatograph (GC) to a time-of-flight inductively coupled plasma time-of-flight mass spectrometer (ICPTOFMS) In order to couple these two instruments, another instrument was designed to provide an isothermal atmosphere between the GC and TOFICPMS to expedite rapid gas separations processes. By using gas separations instead of the current wet chemistry processes, the required separation and analysis time of the melt glass significantly decreases. The new instrument would also provide a more detailed analysis of the elemental and isotopic composition of the melt glass. By completing these tasks simultaneously, this significantly decreases the required time to conduct these separations and improves the elemental and isotopic analysis.","PeriodicalId":61566,"journal":{"name":"核科学与技术国际期刊(英文)","volume":"07 1","pages":"84-92"},"PeriodicalIF":0.0,"publicationDate":"2017-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49343795","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

On-Site Calibration Method of Dosimeter Based on X-Ray Source 基于x射线源的剂量计现场标定方法

核科学与技术国际期刊(英文) Pub Date : 2017-04-03 DOI: 10.4236/WJNST.2017.72008

Wenhui Lv, Huiping Guo, N. Lv, Chenyang Tian, K. Zhao, Xiaotian Wang, Yijie Hou

{"title":"On-Site Calibration Method of Dosimeter Based on X-Ray Source","authors":"Wenhui Lv, Huiping Guo, N. Lv, Chenyang Tian, K. Zhao, Xiaotian Wang, Yijie Hou","doi":"10.4236/WJNST.2017.72008","DOIUrl":"https://doi.org/10.4236/WJNST.2017.72008","url":null,"abstract":"The real-time monitoring of environmental radiation dose for nuclear fa-cilities is an important part of safety, in order to guarantee the accuracy of the monitoring results regular calibration is necessary. Around nuclear facilities there are so many environmental dosimeters installed dispers-edly, because of its huge quantity, widely distributed, and in real-time monitoring state; it will cost lots of manpower and finance if it were tak-en to calibrate on standard laboratory; what’s more it will make the en-vironment out of control. To solve the problem of the measurement ac-curacy of the stationary gamma radiation dosimeter, an on-site calibra-tion method is proposed. The radioactive source is X-ray spectrum, and the dose reference instrument which has been calibrated by the national standard laboratory is a high pressure ionization. On-site calibration is divided into two parts; firstly the energy response experiment of dosim-eter for high and low energy is done in the laboratory, and the energy response curve is obtained combining with Monte Carlo simulation; sec-ondly experiment is carried out in the field of the measuring dosimeter, and the substitution method to calibrate the dosimeter is used; finally the calibration coefficient is gotten through energy curve correction. In order to verify the accuracy of on-site calibration method, the calibrated dosimeter is test in the standard laboratory and the error is 3.4%. The re-sult shows that the on-site calibration method using X-ray is feasible, and it can improves the accuracy of the measurement results of the stationary γ-ray instrument; what’s more important is that it has great reference value for the radiation safety management and radiation environment evaluation.","PeriodicalId":61566,"journal":{"name":"核科学与技术国际期刊(英文)","volume":"07 1","pages":"93-102"},"PeriodicalIF":0.0,"publicationDate":"2017-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46462595","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

Numerical Analysis for Transients in External Source Driven Reactors 外部源驱动反应堆瞬态的数值分析

核科学与技术国际期刊(英文) Pub Date : 2017-04-03 DOI: 10.4236/WJNST.2017.72009

Willian Vieira de Abreu, A. Gonçalves, Z. R. Lima

引用次数: 1