最新刊期
      卷 0 ， 期 0 ， 2020
      • YU Xiaohan YANG Yanwu
        Issue 8, (2005)
        摘要：Laser synchrotron source (LSS) is a novel X-ray source that can produce tunable intense monochromatic X-ray pulses. Compton scattering theory for analyzing LSS was reviewed. Main properties of LSS, including X-ray flux, time structure of pulses and energy spectrum were calculated and discussed.  
        关键词：Laser synchrotron source;Compton scattering;X-ray CLC O432.1   
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        发布时间：2021-03-12
      • YANG Yanwu1,2 YU Xiaohan1 1
        Issue 8, (2005)
        摘要：The equation of X-ray flux was deduced with the transverse divergence of electron and laser beams in the interaction area being taken into account. The relationship between the size of electron and laser beams and both X-ray flux and spectra flux was analyzed. The performance of the proposed LSS experimental facility based on the ps, fs electron accelerator of SINAP was calculated with the electron and laser beam sizes at the interacting point being determined by the criteria of maximum spectra flux.  
        关键词：Laser synchrotron source;X-ray flux;Transverse divergence CLC O432.1   
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        发布时间：2021-03-12
      • TANG Yunhui1 HAN Chunming2 BAO Zengkuan1 HUANG Yuying1 HE Wei1 HUA Wei1 1
        Issue 8, (2005)
        摘要：In this article, SRXRF technique was applied on apatite, one of accessory minerals from granitic diorite, Ge’erke Gold Deposit. Chemical composition of the crystal and its fluid inclusion was analysized. Apatite composi-tion shows that the original magma belongs to mafic I-type granites with high light rare earth elements and Nd deple-tion characteristics. Containting Fe and Mn and trace As, Co, Zn the fluid inclusion, reflects hydrothermal liquids from magma as one of material resources of gold mineralization.  
        关键词：Apatite;Fluid inclusion;SRXRF analysis CLC P571   
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        发布时间：2021-03-12
      • ZHAO Jia1,2 CUI Mingqi1 ZHAO Yidong1 ZHOU Kejin1 ZHENG Lei1 ZHU Jie1 SUN Lijuan1 CHEN Kai1 MA Chenyan1 1
        Issue 8, (2005)
        摘要：The diagnostic methods of the front end, the pre-focusing unit and the double crystal monochromator system for BSRF-3B3 beamline are introduced in detail. Primary analysis of the experimental results shows that one of the main reasons for causing low photon flux is an incorrect aligning adjustment of the front end and beamline. It is concluded that quantitative measures are important for diagnosing and adjusting the beamline.  
          
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        发布时间：2021-03-12
      • YU Luyang1,2 CHEN Yongzhong1 LIU Dekang1,3 1
        Issue 8, (2005)
        摘要：A comprehensive introduction is given to the real-time measuring method, which is based on the Pro-grammable Logic Controller ( PLC ) technology and can measure intensity and profile of the beam by a scintillator screen. The whole system has many advantages, such as good reliability, high precision, intuitional measurement, etc. due to the use of the PLC and Labview software.  
        关键词：PLC;Beam profile;Remote control CLC TL506   
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        发布时间：2021-03-12
      • WANG Fangwei LIANG Tianjiao YIN Wen CAO Huibo ZHANG Panlin YAN Qiwei ZHANG Zong ZHANG Jie
        Issue 8, (2005)
        摘要：We report the recent progress on the conceptual design of the target station and neutron scattering spectrometers for the Chinese Spallation Neutron Source (CSNS). The CSNS target station will be constructed with three parts: tungsten targets cooled by heavy water, Be/Fe reflectors and Fe/high-density-iron-aggregate-concrete shields. There will be 3 WING moderators: water (300 K), liquid methane (100 K) and liquid hydrogen (20 K), and 18 horizontal neutron channels for neutron scattering spectrometers. The Monte Carlo simulation shows that the optimized ratio of height to width of the target cross-section is ~1:2.5. With a nuclear power of 100 kW, the pulsed neutron flux is 2.4 × 1016 cm?2·s?1 for a 40 mm× 100 mm× 10 mm × 40 target stack. The emitted heat is about 47 kJ/s, the target temperature is somewhat higher than 90°C with a normal cooling efficiency, and the strain should be lower than 0.2 mm. Initially 5 typical spectrometers are chosen to be constructed, including a high intensity powder diffractometer, a high resolution powder diffractometer, a small angle scattering spectrometer, a reflectometer and a direct geometry inelastic neutron scattering spectrometer. These spectrometers can cover more than 80 % of the neutron scattering applications.  
          
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        发布时间：2021-03-12
      • WU Jian1 DAI Guifu1 LI Jinfang2 ZHAO Yanheng2 ZHANG Xiaohong3 1
        Issue 8, (2005)
        摘要：The results of both 30 keV N + ion implantation and UV irradiation of Streptomyces albus showed com-plicate biological effects. The“saddle shape”pattern of the dose ? dependent curve formed by N + ion implantation with low energy was studied, and it proved that vacuum was not the reason, and in fact, the “saddle shape”curve may be regarded as a HRS/IRR (hyper-radiosensitivity / increased radiaoresistance) effect caused by low dose irradiation. But Streptomyces albus UV irradiated after vacuum treatment only showed IRR effect or hormesis (survival rate >100%). The streptomycin resistance mutation of Streptomyces albus caused by low energy N+ ion implantation and UV irradiation was also studied. The results showed that UV radiation is one effective means for streptomyces albus breeding.  
          
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        发布时间：2021-03-12
      • TANG Yunhui YUAN Wanming WANG Shicheng DONG Jinquan
        Issue 8, (2005)
        摘要：This paper describes problems of standardization of length measurement in fission-track thermochro-nologic research and various factors affecting length measurement. Etching standard and reference samples for length measurement of zircon are proposed based on some experiments.  
        关键词：Fission track;Length measurement;Standardization CLC P597   
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        发布时间：2021-03-12
      • WANG Xiaoyan1 TIAN Junliang2 YANG Mingyi2 LIU Puling2 1
        Issue 8, (2005)
        摘要：There are close linkages between soil loss degree and soil disturbance degree by human. So it is a key problem to know that how human activity affects soil loss. In this paper, to analyse the correlation of 137Cs loss degree with hillslopes’ cultivated histories, the concentrations of 137Cs on different kinds of loessial hillslopes with different cultivated histories, abandoned ages and different patterns of reforestation are studied. The result shows that there is a linear relationship among 137Cs areal concentrations, cultivation ages and slope gradients. The regressive equation is as follows: X= 2356.79 - 22.77 t - 35.53 S . Variant coefficient of 137Cs areal concentration is 80.11% among hillslopes with different abandonment ages. It is also deduced that 137Cs areal concentration is affected primarily by abandon-ment ages of hillslopes. The 137Cs loss rates of hillslopes with different vegetation restoration manners show signifi-cant differences, as a whole, autogenic restoration < constructing ecological forest < constructing economic forest in Yangou watershed. The history of land utilization is therefore considered to be the main cause that affects 137Cs area concentrations on hillslopes.  
        关键词：137Cs;Areal concentration;Cultivated ages;Correlation analysis;Loessial hillslope CLC S157.1   
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        发布时间：2021-03-12
      • MA Lei CAO yun ZHAO Hongwei ZHANG Zimin FENG Yucheng LI Xixia
        Issue 8, (2005)
        摘要：To satisfy the requirements of HIRFL (Heavy Ion Research Facility in Lanzhou), a series of experiments have been made to produce metallic ion beams. By now, numerous methods have been tested, in which MIVOC (Metallic Ion from Volatile Compounds) method presented very good results. The emphasis of our researches was put upon the production of iron and nickel ions with different high charged states, among which 210 eμA Fe11+, 175 eμA Fe12+, 142 eμA Fe13+, 25 eμA Fe16+, 64 eμA Ni10+, 57 eμA Ni13+, 31 eμA Ni15+ and 15 eμ ANi16+ are typical. In this paper, two representative spectra of high charged state metallic ions, as well as some main parameters of working station (ECR ion source ) are given, and some discussion is also made.  
        关键词：Metallic volatile compounds;ECR ion source;Saturated vapour pressure;High charged state CLC TL5   
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        发布时间：2021-03-12
      • MA Yanliang OUYANG Xiaoping WANG Qunshu LI Gang LI Chunhua
        Issue 8, (2005)
        摘要：The sensitivity of a slot-collimated PIN fission chamber to gamma rays has been calculated by using MCNP-4B code. Based on the theoretical data and the measured 14 MeV neutron sensitivities, the n/γ discriminations for various configurations of the system have been obtained. The results indicate that the design of the system can meet the needs of practical measurements with n/γ discrimination of more than 5.  
          
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        发布时间：2021-03-12
      • XIA Jingguang1,2 LI Wenjian1 WEI Wei1,2 ZHAO Jing1,2 JIN Xiaodong1,2 GAO Qingxiang3 1
        Issue 8, (2005)
        摘要：Exponentially growing human tumor cell lines were γ -irradiated with a dose of 3Gy. The DNA content and percentage of each cell-cycle phase were obtained with flow cytometry. Results indicated that for SMMC-7721, hepG2 and HO-8910 cells, G2/M accumulation was prominently induced by irradiation and the maximal accumulation appeared at 12 h after treatment, and that S phase just displayed temporal accumulation, i.e. S phase cells accumulated at 6 h after irradiation, and thereafter decreased close to or below the level of un-irradiated cells, and that for Hela cells both G2/M and S phase accumulation were pronouncedly triggered by irradiation. It is suggested that there remain differences in activation and maintenance of cell cycle checkpoints after irradiation among these four tumor cell lines.  
        关键词：Ionizing radiation;Tumor cells;Cell cycle;Cell cycle checkpoint CLC Q691   
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        发布时间：2021-03-12
      • HUANG Wencai SHEN Junkang LI Yong ZHOU Jundong YANG Yi LIU Zengli WU Jinchang
        Issue 8, (2005)
        摘要：With left liver irradiated by 40Gy single-dosed X-rays, 12 rabbits’ liver SPECT with 99mTc-Phy and SPIO-MR imaging were implemented in 3rd—4th day post-irradiation, and pathologic study was carried out at the same time. In our SPECT study, the radioisotope absorption of the irradiated livers decreased in 9 rabbits; and the positive rabbits demonstrated radioactive retention in 24-hour delayed observation. In early-phase SPIO enhanced MR imaging, the irradiated livers of 10 rabbits showed the positive appearance as high-signal region; however, the signal contrast of some rabbits’ livers became weak in 60min delayed-enhanced MRI. In pathologic investigation of livers 4th day post-irradiation, the number of Kupffer cells having swallowed SPIO in irradiated liver was less than that non-irradiated region. So we can conclude that both SPECT and MRI are effective in evaluating early effect of liver injury post-irradiations, i.e. dysfunction of reticuloendothelial system.  
        关键词：Radiation-induced hepatic injury;Single Photon Emission Computed Tomography (SPECT);Magnetic Resonance Imaging (MRI) CLC R575   
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        发布时间：2021-03-12
      • MIAO Weibing LIU Zhuo WU Jing
        Issue 8, (2005)
        摘要：To evaluate the value of the imaging of 99Tcm labeled human immunoglobulin G(HIgG) in the early diag-nosis and the assessment of the therapy of Behcet’s Disease, the imaging was performed on five cases of chronic ery-thema nodosum and six of Behcet’s Disease with the lesions of erythema nodosum, and repeated after the therapy. Five patients of chronic erythema nodosum showed increased uptake of 99Tcm-HIgG in subcutis, and decreased after the therapy. Six of Behcet’s showed intense uptake in subcutis and around the blood vessels, and two of them also showed increased uptake of the joints. The images after the therapy were normal. It is concluded that the imaging of 99Tcm-HIgG is simple, safe and noninvasive, and it will be a help to diagnosis of Behcet’s in early stage, improvement of prognosis and assessment of the therapy.  
        关键词：Behcet’s Disease;Erythema nodosum;99Tc m labeled human immunoglobulin G;Imaging CLC R817   
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        发布时间：2021-03-12
      • HUANG Shengli XU Zizong LI Cheng ZENG Hui
        Issue 8, (2005)
        摘要：We report a kind of cosmic ray telescope of plastic scintillator which is utilized to study the new-type timing detector, Multi-gap Resistive Plate Chamber (MRPC). The telescope is composed of long plastic scintillators and wave-length-shift-fibers (WLSF). The fluorescence photon transport in the scintillator, the time resolution and acceptance of the telescope and the MRPC detector’s efficiency are studied by both experiment and simulation. The results show that the photon transport velocity is uniform and equal to about 150ps/cm in scintillators, the reference time resolution of the telescope system is 70~90 ps with a 788 ps start time(T0), which is gotten by a long scintillator embedded with WLSF. The MRPC detector efficiency is above 90% after simulation calibration and uniform at each cell in whole MRPC module.  
        关键词：Wave length shift fiber (WLSF);Fluorescence photon transport;Reference time;Multi-gap resistive plate chamber (MRPC) CLC O571.1   
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        发布时间：2021-03-12
      • ZHANG Jianxiong ZHANG Jin YAO Honglue
        Issue 8, (2005)
        摘要：The paper introduces the frame principle of a portable natural gamma spectrum. In order to realize spec-trum stabilization, a scaled related curve of temperature and negative high voltage of photo-multiplier-tube (PMT) is used to control negative high voltage of PMT to get stable gain of the instrument system and to realize rough adjust-ing of spectrum stabilization. Then the energy axis of gathered data curve is re-demarcated by using positions of natu-ral gamma radial characteristic peaks to obtain gamma spectra form the curves of pulse-amplitude-count-rate without the process of refine stabilizing spectra in the similar instruments. So, the method in this paper can greatly improve the speed of data acquisition on the same condition of error due to statistical.  
          
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        发布时间：2021-03-12
      • ZHANG Yanmin QIU Weidong GAO Baozeng TAN Chunming LIU Yisi
        Issue 8, (2005)
        摘要：The paper describes the structure and work principle of the radiant source set used for TCM-SCAN mobile 60Co container inspection system. A prototype of the radiation source set has been manufactured. Test results show that the set is reliable, safe, easy to operate and suitable for long-distance transport.  
        关键词：Mobile 60Co container inspection system;Radiant source set CLC TL929   
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        发布时间：2021-03-12
      • SUN Qi1 XI Zhao1 YANG Ruichang2 ZHAO Hua1 WANG XiaoJun1 1
        Issue 8, (2005)
        摘要：The experimental and predictive study of void fraction is very important for the natural circulation and accident analysis in nuclear reactors. However, most of the researches on void fraction were carried out with high mass flux, and the predictions of existing void fraction correlations are quite different in low-flow two-phase flow. Void fraction with low mass flux in adiabatic tube is investigated using single-sensor optical probe in this paper. And then average void fraction is obtained through the integral calculation of local void fraction in the cross-section. The comparisons of existing void fraction correlations with low mass flux experimental data show that most of the correlations overestimate the experimental data, and the predictions of Chexal et al., Dix and GE-Ramp correlations fit the data quite well. Chexal et al. correlation is therefore suggested for the prediction of void fraction with low mass flux two-phase flow according to Vijayan’s work.  
          
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        发布时间：2021-03-12
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