最新刊期
      卷 0 ， 期 0 ， 2020
      • ZHAO Yuda1,2 HENG Yuekun2 SUN Zhijia2 WU Jinjie2 WANG Yifang2 1
        Issue 4, (2008)
        摘要：Properties of the scintillator bars are very important to the goal of 90 ps time resolution of the TOF detec-tor on BESIII.The mechanical sizes were measured.The scintillator bars were piled up to measure the effective at-tenuation length and relative light output by cosmic rays.The positions hit by cosmic rays were deduced by time in-formation acquired from the PMTs at the two ends of the scintillators.The results show that the scintillators is very good in quality for BESIII TOF.  
        关键词：BESIII;TOF;Scintillator;Attenuation length;Light output   
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        发布时间：2021-03-12
      • FENG Zhongjun WANG Xiao DU Hanwen YIN Lixin
        Issue 4, (2008)
        摘要：Beam stability is one of the most important requirements for Shanghai free electron laser(SFEL)project,which will be a huge scientific platform for science research and technology development in China.However,ground vibration is one of the main factors affecting the beam stability.In this paper,we report the results of ground vibration measurements on 24-hour basis at points in a line of 450 m.Vibrations at different positions,hours,frequency bands and directions were analyzed,and amplitudes of the vibrations were compared with similar projects in the world.  
        关键词：FEL;Beam stability;Vibration measurement   
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        发布时间：2021-03-12
      • WANG Yuzhu1 JIA Quanjie1 CHEN Yu1 XUE Xianying1 JIANG Xiaoming1 CUI Jian2 LIN Jianhui2 JIANG Zuimin2 HE Qing3 1
        Issue 4, (2008)
        摘要：Synchrotron radiation X-ray was used to carry out the grazing incidence small angle X-ray scattering(GISAXS)studies on GeSi quantum dots(QDs).The QDs sample was grown by molecular beam epitaxy method.Is-GISAXS program was used to simulate the GISAXS experiment data,the input parameters such as shape,size and inter-islands distance were obtained from atomic force microscopy observation,and the Distorted Wave Born Ap-proximation theory and appropriate distribution function were employed to simulate the 1D and 2D GISAXS experi-ment pattern.The simulated results fit the experiment data very well,which proves that the GISAXS is an effective method to probe the microstructure information about shape,size,and distribution of GeSi QDs.  
        关键词：GeSi;Quantum dots;Grazing incidence small angle X-ray scattering(GISAXS)   
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        发布时间：2021-03-12
      • WANG Kefan1,2 XU Pengshou2 ZHANG Weifeng1 GU Yuzong1 ZHENG Haiwu1 1
        Issue 4, (2008)
        摘要：An ultra-thin oxide film was obtained by oxidizing the H-terminated Si(001)surface by absolute C2H5OH solution.AFM observations showed that surface of the oxide film was very flat.Synchrotron radiation photoelectron spectroscopy(SRPES)analysis demonstrated that the oxide film was mainly composed of SiO2,with an average thickness of about 0.24 nm.At 500℃ of the substrate temperature,Ge quantum dots(QDs)of 9.5×1010 cm-2 in density and(25±5)nm in size were grown successfully on the SiO2 film.The result indicates that the SiO2 film made by wet-chemical method can act as epitaxial surface to grow Ge QDs of decreased size and increased density.  
        关键词：Silicon oxide film;Synchrotron radiation photoelectron spectroscopy(SRPES);Wet-chemical method;Ge quantum dots   
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        发布时间：2021-03-12
      • ZOU Yongxiang1,2 WU Jianping1 1
        Issue 4, (2008)
        摘要：Based on analysis of X-ray spectra noise,basic theories of multi-resolution analysis are introduced,and applied to denoise for X-ray fluorescence(XRF)spectra.The maxima of the noise and signal wavelet transform in-crease with the signal amplitude,hence significant difference,and the multi-resolution analysis is better than other treatments in noise reduction,as was conf.Experiments show that the method computes rapidly,with desirable results in determination of low content elements.  
        关键词：Multiresolution analysis;Energy dispersive X-ray spectra;Noise elimination;Weak peak detection   
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        发布时间：2021-03-12
      • CAI Minghui1 HAN Jianwei1 YU Jinxiang2 1
        Issue 4, (2008)
        摘要：A facility to generate atomic oxygen was developed.It consists of a PIG ion source with a permanent magnet,two electrode extraction systems,an electron deflector,an einzel lens,an ion decelerating electrode and a sample bracket.At present,5 eV O-ion beam flux is about 1014～1015 cm-2·s-1.Erosion behaviors of Kapton films were studied.The results indicate the facility can satisfy the need of ground-based simulation experiment.  
        关键词：Atomic oxygen;Negative ion;PIG ion source;Kapton   
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        发布时间：2021-03-12
      • ZHENG Yuzhan1,2 LU Wu1 REN Diyuan1 WANG Gaili1,2 WEN Lin3 SUN Jing3 1
        Issue 4, (2008)
        摘要：Radiation effects and room-temperature annealing behaviors of bipolar operational amplifiers(op amps)of the same type but different manufacturers are investigated in this paper.It was found that the radiation effects of the same type op amps differed a lot among the manufacturers.The main reasons of the radiation-effect difference are analyzed and discussed,and radiation effects at high and low dose rates are explained.The damage enhancement fac-tor and annealing factor of the op amps are calculated,and the biggest difference of the enhancement factor among different manufacturers is about 8.  
        关键词：Bipolar operational amplifier;60Co gamma radiation;Radiation effect;Enhancement factor   
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        发布时间：2021-03-12
      • YANG Yaxin1 WU Yamei1 WU Xinmin1 LIN Jun2 LI Shuzhen2 1
        Issue 4, (2008)
        摘要：Mǒssbauer spectroscopy,X-ray diffraction(XRD)and Fourier transform infrared spectroscopy(FT-IR)were used to study trace iron-bearing mineral combination in uranium field,alteration rock and surrounding rock at 338 uranium deposit of Xiazhuang granite-type uranium ore field,Guangdong,China.The results show that the main iron-bearing mineral in ore-vein is pyrite.The alternation belt contains mainly chlorite and a little lepidocrocite,with less content of pyrite than in ore-vein.There are more original minerals in surrounding rock(diabase of weak alterna-tion)than other belts.The pyrite content decreases with increasing distance of the sampling point to the ore belt.And the chlorite content is the highest in alternation belt.The ore-vein of uraninite,alternation belt and diabase vein of weak alternation can be distinguished,and the range of alternation belt is confirmed with Mǒssbauer spectroscopy,XRD and FT-IR.  
        关键词：Mossbauer spectroscopy;X-ray diffraction(XRD);Fourier transform infrared spectroscopy(FT-IR);Uranium deposit;Iron-bearing mineral   
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        发布时间：2021-03-12
      • LIU Zhaomin1 QIN Li1 ZU Jianhua1 Akio Katakai2 Takanobu Sugo2 Keizo Makuuchi2 1
        Issue 4, (2008)
        摘要：HDPE films irradiated to 200 kGy in N2 were grafted with vinyl benzyltrimethylammonium chloride(VBTAC)to synthesize a strong base anion-exchange membrane.Comonomer grafting technique was used owing to the difficulty of direct graft polymerization of VBTAC onto polyethylene.Dimethylaminoethyl methacrylate(DMAEMA),a relative weak acid monomer,was selected as a co-monomer to promote graft polymerization of VBTAC.The grafting conditions,as well as the compositions of grafted films were investigated.The distribution of grafted basic group in polymer substrate was measured by an X-ray microanalyzer.  
        关键词：Preirradiation grafting;VBTAC;Comonomer grafting;DMAEMA;HDPE film;Anion-exchange;X-ray microanalyzer   
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        发布时间：2021-03-12
      • SHAN Ting CHEN Jie YANG Liming JIE Shaowei QIAN Qiang LIN Han FAN Jinchen CAO Fangqi
        Issue 4, (2008)
        摘要：A β-cyclodextrin(β-CD)based monomer(MAH-β-CD)containing vinyl and carboxyl functional groups was synthesized by reaction of β-CD with maleic anhydride(MAH).By copolymerization of the monomer with acrylamide(AAm),a novel hydrogel,poly(AAm-co-MAH-β-CD)with pH and ionic strength sensitivities plus molecular inclusion function,was obtained by irradiating the aqueous solution mixture of AAm and MAH-β-CD with electron beam.The effect of the feed ratio of components and irradiation dose on the swelling and deswelling properties of the hydrogel was systematically studied.Swelling ratio of the hydrogel was tested under different environment of pH and ionic strength.The results indicate that the copolymer hydrogels did not show any noticeable change in swelling at lower pH(pH<5).However,they showed an abrupt increase in swelling at pH 5～8 due to the ionization of carboxyl groups.  
        关键词：β-Cyclodextrin;Acrylamide;Radiation;Hydrogel;pH-sensitivity;Ionic strength-sensitivity   
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        发布时间：2021-03-12
      • MEI Ying
        Issue 4, (2008)
        摘要：Radioactive methyl-iodide method is an important method for on-site test of iodine adsorbers.In this pa-per,not only principle of the test and entire process of the test are given,but also the equipments we developed are given.Practice in the last a few years proved that the equipment for on-site test with radioactive methyl-iodide method is effective and reliable,and is ready for wide applications.  
        关键词：Iodine adsorber;Site test;Radioactive methyl-iodide method;Factor of purification   
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        发布时间：2021-03-12
      • SUN Xiaoyang1 LUO Jiarong1,2 JI Zhenshan1 WU Yicun1 1
        Issue 4, (2008)
        摘要：The superconducting tokamak is totally different from the ordinary tokamak and it has special running style and higher risk.The safety and interlock system is a very important and essential part of tokamak.EAST is the first whole superconducting tokamak.It is described the main running risk,the way to be used reducing and avoiding risk and the mechanism which will be used when the serious failure takes place in this paper.And we also describe the way to design and implementation of safety and interlock system of EAST tokamak.The system has been used successfully in the experiment and EAST has got its first plasma in September 2006.  
        关键词：Superconducting tokamak;Safety guard;Interlock;EAST(Experimental Advanced Superconducting Tokamak)   
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        发布时间：2021-03-12
      • ZHAO Lei LIU Shubin XIAN Ze AN Qi
        Issue 4, (2008)
        摘要：In this paper,a multiple-channel high speed preamplifier module with dual-gain is presented,together with its design principle,test methods and performance parameter.By proper choice of the chips and careful circuit design,the preamplifier accomplishes a fine performance in high speed analog signal processing.The 3 dB bandwidth is above 440 MHz for gain factor of 2 and 280 MHz for gain factor of 8,with the leading edge time of less than 2 ns.The preamplifier module has been used in the research project of β-delayed neutron emission of radionuclides in neutron-rich region.  
        关键词：Preamplifier;Bandwidth;Frequency response;Linear dynamic range;CFD(Constant-Fraction Discriminator)   
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        发布时间：2021-03-12
      • YAN Ji1,2 TANG Shibiao1 LIANG Ping1 JIANG Lianjun1 YIN Zejie1 1
        Issue 4, (2008)
        摘要：HL-2A is China’s first Tokamak device with divertor configuration(magnetic confinement controlled nu-clear fusion device).To find out the details of on-going fusion reaction at different times is of important significance in achieving controlled nuclear fusion.We developed a new type multi-channel time-division integrator for HL-2A.It has functions of automatic cutting off negative pulse of the input signals,optional integrating time division spacing 0.2～1 ms,TTL starting trigger signal,automatic regularly work 20 s,and integrating 10 channel at the same time.  
        关键词：HL-2A;Time-division integrate   
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        发布时间：2021-03-12
      • NIU Dongxiao1 FENG Xiaolu1,2 CAI Xiangzhou1 SHEN Wenqing1 1
        Issue 4, (2008)
        摘要：Scanning Probe Microscopy(SPM)is a powerful tool for detecting surface properties of nanomaterials.Preparing sample is the key process for SPM imaging.Detecting nanoparticles with SPM often faces the problem that the nanoparticles are usually repolymerized by the molecular force and form nanoparticle-reunions in the process of preparing SPM specimens.To conquer this difficulty,we propose a new method for preparing SPM nanoparticle specimens by soft microprinting combined with enhanced diffusing,in which proper nanoparticle dispersal system can be formed on the substrate surface separated in the liquor nano-film after soft-lithographed.Experiments vali-dated that it is an available artifice for preparing nanoparticle sample in SPM detecting.  
        关键词：Nanoparticles;Scanning probe microscopy(SPM);Repolymerization;Soft-lithography;Diffusion   
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        发布时间：2021-03-12
      • ZHANG Jiahua1 BAO Borong2 CHEN Guanyin3 ZHANG Sunxi3 1
        Issue 4, (2008)
        摘要：Greenhouse effect caused by fossil fuel electric power station is a matter of worldwide concern.Development of nuclear power,a clean energy source,is an important measure to solve the problem.For sustained development of nuclear power,re-generated nuclear power is necessary.The paper presents the properties of U-Pu re-generated nuclear fuel and Th-U re-generated nuclear fuel,with specially emphasis on perspective of Th-U re-generated nuclear fuel.  
        关键词：Nuclear power;Re-generated nuclear fuel;U-Pu nuclear fuel;Th-U nuclear fuel   
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        发布时间：2021-03-12
      • XU Lijun CHEN Kesheng YE Hongsheng LIN Min CHEN Yundong WU Changping LI Huazhi
        Issue 4, (2008)
        摘要：Short-lived 138Cs can be separated from fission products by starting the separation from its parent nuclide 138Xe.A setup with freezing cold trap was developed to separate inert gas nuclides.The theory is based on that dif-ferent gases have different saturated vapor pressures.With gas-jet recoil transportation technology,the setup has been applied successfully in the separation of 138Cs from complicated fission products.Decontamination factors of main γ-emitters are higher than 104 and no other contaminators such as Kr,Rb nuclides are found.  
        关键词：Cold trap;Separation;Cesium-138;Parent nuclide;Saturated vapor pressure   
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        发布时间：2021-03-12
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