最新刊期
      卷 0 ， 期 0 ， 2020
      • YUAN Jing,LUO Liqiang
        Vol. 37, Issue 8, Article number: 080101(2014) DOI: 10.11889/j.0253-3219.2014.hjs.37.080101
        摘要：Background: Synchrotron radiation micro probe analysis technique has been improved rapidly in recent years. Accurate qualitative or quantitative information on the interest element in environmental and biological samples such as atmospheric particles, soil, plant and earthworm plays a crucial role in the understanding of the effect of these elements in the samples. However, determination of these samples with complex matrices is a difficulty in multiple disciplines. With the rapid development of this area, the synchrotron-based techniques have been introduced to this area and have been widely used in analyzing various complex samples due to its superiority in fast and non-destructive determination. Purpose: In this review, the synchrotron source and its advantages in investigation on elemental analysis of the complex natural samples are introduced. Then, the applications of Synchrotron micro-X-ray fluorescence (μ-SXRF) and Synchrotron X-ray absorption fine spectroscopy (XAFS) in atmospheric particles, soil, plant and earthworm are reviewed, covering the distribution and the speciation of elements in these samples. Methods: μ-SXRF permits in situ mapping of biologically important elements of the sample even at sub-micrometer scale so that the spatially resolved element distribution maps can be obtained. XAFS allows determination of the speciation of high heterogeneity samples by providing the element oxidation state and local coordination environment. Results and Conclusion: μ-SXRF and XAFS have been widely used in element distribution and speciation of nature samples, especially for micro scale samples or micro area of samples such as atmospheric particles, soil, plant and earthworm. It is relevant to study thoroughly the presence, source, mobilization and fate of the elements using the information. Some challenges and future perspectives of the research and the tendency of development of synchrotron radiation technology have also been suggested. Abstract  
        关键词：Synchrotron radiation;Synchrotron micro-X-ray fluorescence (μ-SXRF);X-ray absorption fine spectroscopy (XAFS);Atmospheric particles;Soil;Plant and animal   
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        发布时间：2021-03-03
      • ZHU Guozhen,GE Liangquan,LI Zhichun
        Vol. 37, Issue 8, Article number: 080201(2014) DOI: 10.11889/j.0253-3219.2014.hjs.37.080201
        摘要：Background: The value of indoor radon concentrations is related to the health of public, the measurement and evaluating had been attracting much attention from the scientific researcher. Purpose: The aim is to measure the indoor radon concentrations in a laboratory of university located in Chengdu, and estimate the annual effective dose of radon for researcher and staff. Methods: The measuring site and estimating dose were chosen according to the requirement of Specifications for monitoring of indoor radon and its decay products (GBZ/T 182-2006). Results: The average radon concentration in the laboratory building is 20.99±13.87 Bq?m?3, which is conforming to the demands of Basic standards for protection against ionizing radiation and for the safety of radiation sources; the value of indoor radon concentrations is related to the area of the room. The annual effective dose of the science researchers in the laboratory building is 0.24 mSv, which is lower than the world average dose. Conclusion: The annual effective dose of radon people in the laboratory received is in the normal background level; radon and its daughter don’t bring additional dose. The instrument measuring radon in balloon method is simple in operation and portable; as direct scale based on the instrument can calculate the calibration factor without standard radon chamber, in the range of error, the calibration factor can satisfy the need of actual work. Abstract  
        关键词：Instrument measuring radon in balloon method;Radon concentration;Annual effective dose   
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        发布时间：2021-03-03
      • CHEN Qiping,HE Jiaheng,WANG Guanquan,LUO Shunzhong,MA Zongping,LIU Guoping
        Vol. 37, Issue 8, Article number: 080301(2014) DOI: 10.11889/j.0253-3219.2014.hjs.37.080301
        摘要：Background: The rapid development of nuclear technique makes the actinides uranium be used more and more widely, which increases the chances of nuclear accident. Accident caused by radiation not only displays direct illumination to body surface, but more serious the internal. Purpose: The aim is to investigate whether fullerenes derivatives have protective effect on acute liver injury. Methods: In this work, we modified fullerenes based on their strong radical scavenging function and investigated whether fullerene derivative has a protective effect against liver mitochondria damage in mice. Results: Experimental results show that the radiation can generate strong free radical and damage on mitochondria. Damages are as follows: mitochondria swelling, lipid peroxidation producing and malondialdehyde (MDA) generating. Conclusion: Chelating agent can significantly reduce the swelling of mitochondria and the formation of MDA, so as to maintain the integrity structure and function of mitochondria. Abstract  
        关键词：Fullerene derivatives;Mitochondria;X-ray;Free radical   
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        发布时间：2021-03-03
      • HE Shanzhen,WANG Shuxia,WANG Peng,LI Shilei,TANG Ganghua
        Vol. 37, Issue 8, Article number: 080302(2014) DOI: 10.11889/j.0253-3219.2014.hjs.37.080302
        摘要：Background: Positron emission tomography (PET) is in rapidly developing as a powerful imaging technique for diagnosis, efficacy evaluation and prognosis of tumor. In contrast to 18F-FDG, the amino acid tracers were helpful additional tools for differentiating tumor tissue and inflammation, edematous, necrotic and fibrotic tissue because of their low uptake in those tissues, so that amino acid tracers appear to be more specific than the widely used 18F-FDG. As a result, a number of attempts have been undertaken for radio-synthesis of amino acid with short half-life nuclide 18F and 11C. Purpose: The aim is to review and discuss the present knowledge on synthesis methods and preliminary clinic application of labeling amino acid. Methods: The advances on the synthesis methods and preliminary clinic application of labeling amino acid in recent years were introduced and discussed. Results: In recent years, many new 18F or 11C-labeled amino acids have been developed and their preliminary clinic applications were studied. Conclusion: The review provides an overview of this class of radiolabeled amino acids and highlights the current synthesis status and the key preliminary clinic applications. Abstract  
          
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        发布时间：2021-03-03
      • ZHAO Cuilan,CHEN Lihong,LI Yongping
        Vol. 37, Issue 8, Article number: 080401(2014) DOI: 10.11889/j.0253-3219.2014.hjs.37.080401
        摘要：Background: The coded aperture collimator becomes a hot research topic in the field of nuclear radiation imaging. Purpose: This paper mainly introduces a Modified Uniformly Redundant Arrays (MURA) based on new portable radiation imaging system and focuses on the decoding process of MURA coded aperture collimator imaging system, near field correction, etc. Methods: Two kinds of decoding matrix algorithms named: δ decoding algorithm and finely sampling balance decoding (FSBD) algorithm are investigated in details. Comparison between the two decoding algorithms was conducted by MATLAB simulation, and imaging experiments using both a single and multiple point sources. Results: The experimental results show that the FSBD algorithm outperforms the δ decoding algorithm, and the imaging system represents clear reconstructed images of multiple point sources with correct position of radiation sources. Conclusion: FSBD algorithm is a better decoding approach for radiation imaging system using MURA coded aperture collimator.Cited  
        关键词：Radiation imaging;Modified Uniformly Redundant Arrays (MURA);δdecoding algorithm;Finely sampling balanced decoding (FSBD) algorithm   
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        发布时间：2021-03-03
      • MA Ruigang,CUI Baoqun,MA Yingjun,HUANG Qinghua,TANG Bing,CHEN Lihua
        Vol. 37, Issue 8, Article number: 080402(2014) DOI: 10.11889/j.0253-3219.2014.hjs.37.080402
        摘要：Background: The Beijing Radioactive Isotope Separator Online (BRISOL) is one of the important experimental equipment in the improving project of Tandem accelerator. Its performance is heavily affected by the stability of the weak current measurement system. Purpose: The aim is to develop a robust weak current amplifier for the low level measurement system of BRISOL. Methods: After analyses of the composition and the difficulties of weak beam measurement system in BRISOL, effectual measures were taken to design the weak current amplifier. Many factors that may influence the low current measurement and some design problems were paid special attention to the implementation of this weak current amplifier by using specific design software for circuit layout, programmable logic controllor (PLC) for baseline drift correction, etc. Results: Considerable experimental tests were carried out in a variety of harsh environments for the weak current measurement system in BRISOL, and promising results were achieved. Conclusion: The anti-interference ability and reliability of the weak current amplifier were verified. The performance of the weak current measurement system can meet the requirements of beam diagnostic system. Abstract  
        关键词：Radioactive isotope separator online;Weak current measurement;Amplifier;Noise;Anti-interference   
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        发布时间：2021-03-03
      • YAN Siqi,LU Xiaolong,DANG Bingrong,DUAN Limin,LI Wenjian,LI Zhankui,SONG Haihong,YAN Yan,WEI Zheng,WANG Jie,WANG Junrun,YAO Zeen
        Vol. 37, Issue 8, Article number: 080403(2014) DOI: 10.11889/j.0253-3219.2014.hjs.37.080403
        摘要：Background: Heavy ion track is one kind of very important information for diotherapy study. Purpose: The aim is to study the spatial distribution of the heavy ions energy deposition when they pass through certain matter, especially the biological tissue. Methods: A heavy ion track imaging detector system which is based on gas avalanche chamber and charge-coupled device (CCD) optical readout system was developed. Preliminary experimental test was performed, in which α particle radiated from 239Pu was used as the incident particle. Results: α particle track imaging was achieved successfully. It is found that α particle track is closely related to the gas pressure in the avalanche chamber and the exposure time of the CCD camera. According to analyzing the data of α particle track under the condition of gas pressure equivalent to 15 hPa and exposure time equivalent to 10 s, it is proved that the track structure is axisymmetric. With incident depth increasing, the track spread decreases gradually, and the image points density increases. Conclusion: We developed the heavy ion track imaging detector system which can achieve α particle track imaging successfully, and some preliminary law of charged particle track can be found. Abstract  
          
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        发布时间：2021-03-03
      • ZHANG Kai,NIE Yangbo,BAO Jie,RUAN Xichao,REN Jie,HAN Rui,HUANG Hanxiong,LI Xia,ZHOU Zuying
        Vol. 37, Issue 8, Article number: 080501(2014) DOI: 10.11889/j.0253-3219.2014.hjs.37.080501
        摘要：Background: Integral experiment is an important means to verify the accuracy of the evaluated nuclear data. The reliability of the experimental system is important for evaluating nuclear data. Purpose: In order to check the reliability of the experimental system in China Institute of Atomic Energy (CIAE), the standard sample method was used. Methods: The neutron leakage spectra were measured at 47° for polyethylene sample (10 cm×10 cm×5 cm) and at 30° for water sample (?10 cm×5 cm). The experimental results (E) have been compared with the calculated ones (C) which have been simulated using MCNP5 code. Results: The results showed that the ratios of n-p scattering area (C/E values) were consistent in the uncertainty of 2% for both samples. Conclusion: This experiment confirmed that the nuclear data measured by this experimental system was reliable. Abstract  
        关键词：Integral experiment;Standard sample method;Time-of-flight (TOF);n-p scatter;C/E values   
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        发布时间：2021-03-03
      • WANG Feipeng,SHEN Shuifa,YAN Yupeng
        Vol. 37, Issue 8, Article number: 080502(2014) DOI: 10.11889/j.0253-3219.2014.hjs.37.080502
        摘要：Background: 178Hfm2 isomer is considered the most suitable candidate to study the depletion of its stored energy induced by low-energy X-ray in recent decades. Purpose: The aim is to research whether there exist potential gateway states which may trigger gamma-ray emission from the K?=16+ isomer with low-energy photons. Methods: The projected shell model is at first used to study the multi-quasiparticle and collective excitation states of 178Hf. Results: The results show that the 16+ isomer lies well separated in energy from other states. But when the configuration-constrained (diabatic blocking) calculations, with inclusion of ?-deformation, are performed to study the multi-quasiparticle excitation states of 178Hf, it appears that three levels can be the most likely candidates for photodeexcitation of the 16+ isomer. Conclusion: The Potential Energy Surface (PES) calculations in the present work suggest that this nucleus is rigid to axially asymmetric shapes. Abstract  
          
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        发布时间：2021-03-03
      • LI Yangjuan,CHENG Zhiqiang,ZHANG Huanqi,ZHANG Guoxin,LI Sasa,LONG Dewu,WU Guozhong,LI Qingnuan
        Vol. 37, Issue 8, Article number: 080601(2014) DOI: 10.11889/j.0253-3219.2014.hjs.37.080601
        摘要：Background: As a pyroprocess, the fluoride volatility process is developed to recover uranium from spent nuclear fuel. And the fluoride adsorption technology is usually applied as a mean for the purification and collection of UF6 in the fluoride volatility process. Purpose: A novel technique for preparation of the adsorbent NaF used for the purification of uranium in the fluoride volatile process has been developed. Methods: In this work, the polymer sodium carboxymethyl cellulose (CMC), NaF and water were used as raw materials, and porous NaF adsorbent particles were made by molding and sintering process. The characteristics of the adsorbent particles were analyzed and characterized. Results: Specific surface area of the adsorbent was 0.3–0.4m2?g?1, porosity was 40%–45% and particle strength was 60–80N. At room temperature, the equilibrium adsorption capacity of MoF6 was about 37.8 mg MoF6/1g NaF. The energy dispersive spectrometry (EDS) analytical result indicated that the MoF6 was able to diffuse into the interior of the adsorbent particles through their pores. Conclusion: The NaF adsorbent developed in this study is expected to be used for further purification of uranium in fluoride volatile process. Abstract  
        关键词：NaF;Adsorbent;Porous;MoF6   
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        发布时间：2021-03-03
      • LYU Dan,LI Ruirou,SONG Fengli,WANG Shijun,ZHANG Yue
        Vol. 37, Issue 8, Article number: 080602(2014) DOI: 10.11889/j.0253-3219.2014.hjs.37.080602
        摘要：Background: The accident classification method and acceptance criteria of spent fuel reprocessing facility used in China come from the regulatory requirements and the engineering experience of the USA about 40 years ago. Nowadays, these engineering projects have not been in operation, and part of former regulatory requirements have been withdrawn and replaced by newly issued documents. Purpose: Through comparison of the current regulatory requirements and previous engineering experience on the accident classification method and acceptance criteria of spent reprocessing facility in the USA, we aimed to offer some suggestions or advice for the development of accident analysis method ology in China. Methods: Investigation of the current regulatory requirements of the accident classification method and acceptance criteria for spent fuel reprocessing facility in the USA was carried out, and their comparison with the previous engineering practice was implemented. Results: On the basis of the historical engineering experience, the current regulatory requirements have introduced the risk assessment method into the accident classification and acceptance judgment. The current regulations require the license applicants to identify the hazards of concern through hazard risk analysis of the whole facility, and further, to assess both the likelihood of occurrence and the consequence of accidents by risk matrix. The marginal accidents in the whole accident scope consist of not only the design basis accidents, which were usually discussed as the accident margin for accident analysis in historical engineering experience, but also the incidents with low-level consequence but high-level likelihood of occurrence. The risk boundary in the risk matrix serves as the accident acceptance criteria; while in the historical engineering experience, the accident acceptance criteria only focused on the limit of individual total radiation dose on the boundary of the exclusion area. Conclusion: The current regulatory requirements of the accident classification method and acceptance criteria for spent fuel reprocessing facility in the USA have made a remarkable development from previous engineering experience. These requirements include the evaluation of effectiveness of engineering measures, and the assessment of the safety balance of the facility design, which might be a good reference for future development of accident analysis methodology in China. Abstract  
        关键词：Spent fuel reprocessing;Accident classification method;Accident acceptance criteria   
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        发布时间：2021-03-03
      • LU Yang,HE Jian,ZHU Zhiqiang,HUANG Qunying
        Vol. 37, Issue 8, Article number: 080603(2014) DOI: 10.11889/j.0253-3219.2014.hjs.37.080603
        摘要：Background: Lead-Bismuth Eutectic (LBE) was selected as one of main coolants for Accelerator Driven sub-critical System (ADS). And the flow rate of LBE loop was measured in a high temperature and strong corrosion environment. Electromagnetic flow-meter (EMFM) was one of the main equipment used to measure flow rate of LBE in the world. Research indicated that calibration technique is significant for EMFM measurement. Purpose: The aim was to find the calibrated formula of the EMFM we designed, and evaluate its accuracy and applicablity. Methods: To study the flow rate measurement of LBE, FDS team has built a liquid LBE loop—PREKY. Through an experiment study on flow rate measurement of LBE in PREKY loop by using the EMFM, we measured a series of data. The calibrated factor was found by comparison between calculated flow rate and standard flow rate. Results: Through the experiment, we got a calibrated formula of the designed EMFM under the condition of LBE at the temperature of 350oC, and the flow rate of 3.8–4.5m3?h?1. The error of this calibrated formula was within ?4.9%–5.9%. Conclusion: The calibration formula can be used in the upcoming flow rate measurement of this EMFM at 350oC, and provide a reference for LBE flow rate from 300oC to 400oC. Abstract  
          
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        发布时间：2021-03-03
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