最新刊期
      卷 0 ， 期 0 ， 2020
      • TONG Yajun1 HE XiaoYe3 ZHAO Yidong2 ZHENG Lei2 XIAO Tiqiao1 WANG Qiuping3 1
        Vol. 32, Issue 5, (2009)
        摘要：High accuracy linear movement in grating monochromators of synchrotron radiation beamline is essential.Usually the linear displacement accuracy requirement is about 1 micron to achieve the spectral resolution.A laser interferometer and an autocollimator are used Beijing Synchrotron Radiation Facility(BSRF) to measure linear displacement of the mechanism and to calibrate the linear encoder.It measures not only precision of the linear displacement, but also linearity of the movement.Linear displacement mechanism was tested by the system with accuracy of 1.0×10-3 mm and resolution of 7.5×10-5 mm.The linear encoder can give the displacement at an accuracy of RMS=3×10-4 mm within 160 mm range.This system plays an important role for both linear displacement mechanism commissioning and for wavelength calibration of the monochromators.  
        关键词：Linear displacement;Measurement and calibration;Grating monochromator   
        17
        |
        13
        |
        1
        <HTML>
        <L-PDF><Meta-XML>
        <引用本文> <批量引用> 7230488 false
        发布时间：2021-03-12
      • CHEN Liping JIANG Dikui YIN Lixin XU Yi CHEN Yonglin LU Yu
        Vol. 32, Issue 5, (2009)
        摘要：There are 40 bending magnets in the 432-m storage ring of the Shanghai Synchrotron Radiation Facility(SSRF).A total power of 435 kW is delivered by synchrotron radiations when the electron beams pass through the bending magnets.Only a small part of the radiation is extracted into the beamlines and the experiment stations, and the rest has to be absorbed and transferred out of the storage ring.Photon absorbers are placed at different points of the storage ring to intercept the unused synchrotron radiation and align the extracted light.In this paper, the radiation treatment method is discussed and layout of the absorbers is described in detail.The structure of the absorbers, the manufacture and assembly, and performance of the absorbers are introduced.  
        关键词：Accelerator;Synchrotron radiation;Thermal load;Photon absorber   
        11
        |
        11
        |
        1
        <HTML>
        <L-PDF><Meta-XML>
        <引用本文> <批量引用> 7230441 false
        发布时间：2021-03-12
      • MAO Chengwen1,2 YU Xiaohan1 XIAO Tiqiao1 1
        Vol. 32, Issue 5, (2009)
        摘要：Bent elliptical mirrors are often used as X-ray microfocus device in synchrotron radiation beamlines.In this paper, the theory of width-variable bent elliptical microfocus mirror was reviewed.The formula for calculating the required bending moments and residual slope error when the working condition(source distance, grazing incident angle and image distance) of the mirror differed from the designed values was deduced.The microfocus mirror of the SSRF X-ray microfocus beamline was calculated as an example.The results show that, by adjusting the bending moments, a large range of the grazing incident angles and source-to-mirror distances can be of choice, and the resulted additional slope error can be negligible.However, a relatively small change of image distance will result in large slope error.  
        关键词：Synchrotron radiation;X-ray;Microfocusing;Bending elliptical mirror   
        11
        |
        11
        |
        4
        <HTML>
        <L-PDF><Meta-XML>
        <引用本文> <批量引用> 7230967 false
        发布时间：2021-03-12
      • CAO Shuchun1,2 YUAN Ping1 SU Yalong1,2 LI Zhongping1 ZHANG Zimin1 HAN Lixiang1,2 1
        Vol. 32, Issue 5, (2009)
        摘要：The configuration and performance of high voltage generator(HVG) of a high power low-energy electron accelerator, designed for industrial applications, were introduced in this paper.The simulating circuit model parameters of the HVG were determined based on its basic transformer-type working principle, and then the Matlab software was used to simulate steady work condition of the HVG.Furthermore, the instant voltage distribution along the cascades of the HVG was analyzed under the malfunction of breakdown between the high voltage electrode and the ground electrode.After that, the parameters of HVG were partly adjusted according to the simulating result, and performance of the equipment was improved as a result of the adjustment.In addition, the interlayer breakdown between the sections of cascades was simulated by Matlab, and some improving methods were adopted to enhance the performance of HVG for protecting the equipment during the high voltage breakdown.  
        关键词：Electron accelerator;High voltage generator;Simulation   
        11
        |
        12
        |
        0
        <HTML>
        <L-PDF><Meta-XML>
        <引用本文> <批量引用> 7230923 false
        发布时间：2021-03-12
      • HAO Fanhua LIU Xiaoya XIAO Chengjian XIONG Wang ZE Rende GONG Jian HU Side
        Vol. 32, Issue 5, (2009)
        摘要：In this paper, we study the amount and size distribution of aerosol particles formed in an explosion in a sealed metal container in presence of a silver sample.Aerosol samples were collected for different minutes at different time after the explosion.The samples were weighed, and examined by neutron activation analysis, scanning electron microscopy and X-ray diffraction.The results indicated that changes in size distribution of the particles depended on the process combining Brown aggravation and gravitation sedimentation in the container.The aerosol particle size in relatively stable gas phase distributed mainly around 1.8 μm.The Ag particles had a segregating behavior in particles of different sizes.Most Ag aerosol particles under 10 μm size consisted of small polycrystalline aggregates, and the average crystalline size was 27.3 nm.  
        关键词：Sealed explosion;Aerosol;Granularity distribution;Aggravation   
        11
        |
        12
        |
        4
        <HTML>
        <L-PDF><Meta-XML>
        <引用本文> <批量引用> 7230937 false
        发布时间：2021-03-12
      • SHI Feiyue1 YANG Huiling2 MA Jiayi1 ZHAO Jingwu1 ABULIEMU·Aierken3 YANG Kunjie3 ZHAO Nongxiao3 LIU Shengkang1 1
        Vol. 32, Issue 5, (2009)
        摘要：For designing a nondestructive detection system to measure grease stain thickness in pipelines by using γ-ray scattering method, Monte-Carlo simulations were carried out for a pipeline with and without thermal insulation layer(TIL).Response curves of the scattered γ-ray counts from the grease stain thicknesses(d) were obtained, under different source-pipe distances(t) and source-detector distances(h).It was found that the count varied with d in exponential curves.The maximum detectable thickness of the grease stain(dM) became larger with increasing t or h, and the dM with TIL was smaller than that without TIL.The results are of help for performing nondestructive measurement of the grease stain thickness in pipelines.  
        关键词：γ-ray;Scattering;Grease stain thickness;Monte-Carlo simulation;Detected count;Shield   
        13
        |
        12
        |
        0
        <HTML>
        <L-PDF><Meta-XML>
        <引用本文> <批量引用> 7230421 false
        发布时间：2021-03-12
      • LI Yintao LI Linfan ZHANG Yan YAO Side XIE Leidong
        Vol. 32, Issue 5, (2009)
        摘要：Thermal oxidation processes of styrene-butadiene-styrene(SBS) copolymer grafted by γ-rays with maleic anhydride(MAH), and pure SBS, were studied using FT-IR and DSC analysis.The results show that the thermal oxidation process of SBS is a free radical self-catalyzed reaction with both crosslinking and scission and the latter is the main process.The thermal oxidation productions may be alcohol, aldehyde, acid, anhydride, etc.Comparing with pure SBS, the inducing temperature and oxidation time involved in oxidation process of SBS-g-MAH increase due to the reduction of double bond and α-H in PB segment.It can be predicated that the thermo-oxidative stability of SBS-g-MAH would be better than that of SBS in application for polymer modified asphalt.  
        关键词：SBS;Radiation graft;Thermal oxidation;Mechanism   
        13
        |
        11
        |
        1
        <HTML>
        <L-PDF><Meta-XML>
        <引用本文> <批量引用> 7230702 false
        发布时间：2021-03-12
      • ZHENG Jianfei XU Gang WU Minghong JIAO Zheng GUO Xiaoya WAN Xiaojuan LIU Ning
        Vol. 32, Issue 5, (2009)
        摘要：As unique radiolytic products formed in irradiated fat-containing food, alkylcyclobutanones(2-ACBs) can be used to determine history of irradiation and estimate absorbed doses.The cyclobutanone in this study was 2-dodecylcyclobutanone(2-DCB) determined by gas chromatogram with mass spectrum.Pork samples were irradiated to 1-10 kGy by 60Co γ-rays.A linear relationship between 2-DCB concentration and dose was established.In addition, the irradiated pork samples were cooked with a microwave oven and 2-DCB was detected.The results showed that 2-DCB was stable after microwave cooking.  
        关键词：γ irradiate;Pork;2-dodecylcyclobutanone;Microwave   
        10
        |
        11
        |
        2
        <HTML>
        <L-PDF><Meta-XML>
        <引用本文> <批量引用> 7230780 false
        发布时间：2021-03-12
      • XIE Qiaoling1,2 LI Qintao1,3 YANG Shumin1,2 HE Zhoutong1,2 ZHOU Xingtai 1 ZHU Dezhang1 GONG Jinlong1 1
        Vol. 32, Issue 5, (2009)
        摘要：Si nanocone array was fabricated under oblique ion beam bombardment on diamond film-masked Si substrates at room temperature.SEM images of the ion sputtered samples showed that the Si nanocone density was determined by density of the diamond particles on the Si substrate, and topography of the Si nanocones was closely linked with the beam incidence.By increasing the incidence angle from 30° to 75°, apex angle of the Si nanocone decreased from 73° to 23°, and aspect ratio of the Si nanocone increased from 500 nm/360 nm to 2400 nm/600 nm.It was believed that the formation of silicon nanocones using the diamond film mask was attributed to the lower sputtering rate of diamond compared to Si substrate.With increasing incidence angle, the decreasing apex angle and increasing aspect ratio of Si nanocone were attributed to decreased effective diffusion coefficiency and increased sputtering yield induced by the ion beams.  
        关键词：Si nanocones;Ion beam sputtering;Diamond film   
        10
        |
        12
        |
        0
        <HTML>
        <L-PDF><Meta-XML>
        <引用本文> <批量引用> 7230815 false
        发布时间：2021-03-12
      • YUAN Dexiao PAN Yan ZHAO Meijia CHEN Honghong SHAO Cunlin
        Vol. 32, Issue 5, (2009)
        摘要：This work was to explore γ-ray induced radioadaptive response(RAR) in Chinese hamster ovary(CHO) cell lines of different DNA damage repair capacities.CHO-9 cells and the two repair-deficient strains, EM-C11(DNA single strand break repair deficient) and XR-C1(DNA double strand break repair deficient), were irradiated with a priming dose of 0.08 Gy or 0.016 Gy.After 4 or 7 hours, they were irradiated again with a challenging dose of 1 Gy.The micronucleus induction and plating efficiency of the cells were assayed.Under 0.08 Gy priming dose and 4-h interval, just the CHO-9 cells showed RAR, while with the 7-h interval the CHO-9 and EM-C11 showed RAR, but XR-C1 did not.When the cells were pretreated with a lower priming dose of 0.016 Gy in a 4-h time interval, all the three cell lines showed RAR to subsequent 1 Gy irradiation.It can be concluded that RAR is not only related to the priming dose and time interval, but also has close dependence on the ability of DNA damage repair.  
        关键词：Low dose radiation;Adaptive response;DNA repair   
        11
        |
        11
        |
        1
        <HTML>
        <L-PDF><Meta-XML>
        <引用本文> <批量引用> 7230951 false
        发布时间：2021-03-12
      • ZHAI Shijun ZHANG Bin YUAN Hang SU Chenghai
        Vol. 32, Issue 5, (2009)
        摘要：To establish the method radiolabeled monoclonal antibody 10D9 against human costimulatory molecules CD80 with 125I, 10D9 was labeled with 125I using the Iodogen method at room temperature.The labeling efficiency and radiochemical purity were tested with TCA, and the immune activity and stability of the labeling product were analyzed.The optimum labeling condition was 10 μg Iodogen, 20 μg 10D9 and 22.2 MBq Na125I.The reaction time was 8 min at room temperature.The labeled yield was(84.10±3.18)%, and the radiochemical purity was(98.49±1.14)%.The radio-activity of 125I-10D9 was 933.51 MBq/mg.The specific binding efficiency of 125I-10D9 with Daudi cell was(23.21±1.14)%.The radiochemical purity of 125I-10D9 was over 90% after three weeks of mixing with PBS.In conclusion, the method is simple and easy to perform.The labeling efficiency and radiochemical purity is high.The stability of 125I-10D9 is fine in vitro and 125I-10D9 keeps its immune activity after Iodogen labeling.  
        关键词：Monoclonal antibody 10D9;125I;Iodogen   
        11
        |
        12
        |
        3
        <HTML>
        <L-PDF><Meta-XML>
        <引用本文> <批量引用> 7230900 false
        发布时间：2021-03-12
      • LIN Han CHEN Jie QI Haoling SHEN Li FAN Jinchen CAO Fangqi
        Vol. 32, Issue 5, (2009)
        摘要：In this paper, β-cyclodextrin(β-CD)-based water-soluble macromonomer(PEG-β-CD) was synthesized by reaction of β-CD with poly(ethylene glycol) diglycidyl ether(PEGDE).A novel temperature-sensitive hydrogel composed of PEG-β-CD and poly(N-isopropylacrylamide)(PNIPAAm) was prepared by E-beam irradiation.Compared with the normal PNIPAAm hydrogel, the obtained hydrogel had a high swelling ratio at room temperature and exhibited faster shrinking kinetics at temperature close to the lower critical solution temperature(LCST).5-fluorouracil(5-FU) was chosen as a model drug loaded into the hydrogels, and the release results showed the β-cyclodextrin-containing hydrogels prolonged the release time.  
        关键词：β-Cyclodextrin;N-isopropylacrylamide;Radiation polymerization;Temperature-sensitivity Hydrogel;Drug delivery   
        12
        |
        12
        |
        3
        <HTML>
        <L-PDF><Meta-XML>
        <引用本文> <批量引用> 7230801 false
        发布时间：2021-03-12
      • WANG Quanshi LI Hongsheng TANG Ganghua LI Dongli WANG Qiaoyu WU Hubing
        Vol. 32, Issue 5, (2009)
        摘要：Radiopharmaceutical of 18F-FHBG was synthesized and recombinant expression plasmid pLXSN-tk was constructed.The nude mice sub-skin model transplanted with human liver cancer was constructed by subcutaneous implantation of cultured the BEL-7402 liver carcinoma cell lines into the two sides axillary fossa nude mice.The left tumors were used as the control, while the right tumors were used as the experiment group, with the cancer cell being transfected by the pLXSN-tk.PET images were taken at 10, 30, 50, 70, 90, 110, 130, 150, 170, 190 and 210 min after 18F-FHBG injection via the tail veins.The results show that the uncorrected radiochemical yield of 18F-FHBG was 4%-10% and the radiochemical purity was over 95%.The 18F-FHBG PET images indicated that 18F-FHBG uptake of the control did not increase obviously, whereas high activity was observed in the experiment group 50-210 min after 18F-FHBG injection.18F-FHBG uptake of the experiment group increased gradually to 19.772 kBq·mL-1 150 min after 18F-FHBG injection, where the experiment/control tumor ratio was peaked at 4.99.The results indicated that 18F-FHBG PET imaging of HSV1-tk expression in tumors can be used to monitor, in living animals, and expression of theoretical gene.  
        关键词：Nude mice;Xenograft;Tomography;Emission-computed;HSV1-tk;18F-FHBG   
        9
        |
        11
        |
        0
        <HTML>
        <L-PDF><Meta-XML>
        <引用本文> <批量引用> 7230579 false
        发布时间：2021-03-12
      • CHENG Muhua ZHANG Feng CHEN Yi WU Chunxing CHEN Weizhen ZHANG Yong
        Vol. 32, Issue 5, (2009)
        摘要：A 99mTc linear source was made with a plastic cover, and SPECT/CT imaging was performed with a GE Hawkeye hybrid system and patient’s beds under load or nothing.The two kinds of data acquired were reconstructed and fused, and the deviation was quantitatively analyzed by the profiling method.Without load on the patient’s bed, the SPECT and CT images matched perfectly, with the SPECT image center being deviated from that of the CT image at only(1.37±0.96) mm.Under 25-kg load, the deviation of SPECT and CT image centers was(2.21±1.32) and(3.26±1.52) mm for new and old beds, respectively, with the statistical difference of the deviations being P<0.05 between the new and old beds.For the new and old beds under the load or nothing, the deviation of SPECT and CT image centers was significant, P<0.05, with the largest deviation being 6.0 mm.These indicate that the position change of the patient’s bed under load could result in deviation of the SPECT and CT image match, and affect the quality of image fusion.  
        关键词：Scintigraphy;Tomography;Image fusion;Quality control   
        12
        |
        11
        |
        2
        <HTML>
        <L-PDF><Meta-XML>
        <引用本文> <批量引用> 7230910 false
        发布时间：2021-03-12
      • TUO Xianguo WANG Honghui LI Zhe MU Keliang
        Vol. 32, Issue 5, (2009)
        摘要：The frequency generating technique of a slip pulse generator for testing MCA is introduced in this paper.FPGA&DDS is adopted to generate high precision signals.The design and implementation technology of hardware and software are illustrated.Tests show that the frequency rang of the generator is 5 Hz-20 MHz and the error is within ±0.1%.The achievements could be applied in related signal processing area.  
        关键词：Slip pulse;FPGA;DDS;Frequency generator   
        14
        |
        11
        |
        0
        <HTML>
        <L-PDF><Meta-XML>
        <引用本文> <批量引用> 7230454 false
        发布时间：2021-03-12
      • LIU Shubin FENG Changqing YAN Han AN Qi
        Vol. 32, Issue 5, (2009)
        摘要：In this paper, we describe a non-gated charge-to-time converter covering the dynamic range of 180-5000 mV in bipolar input voltage from the 448 pre-amplified outputs of TOF detectors for Beijing Spectrometer Ⅲ at the Beijing Electron Positron Collider(Phase II).With the error of less than 10 mV, the circuits work well for correcting the time-walk effect.This is essential for measurements of the time resolution of better than 25 ps.The converter is simple, stable, and is intended for multi-channel systems.  
        关键词：Time-Walk;Charge;Integrate;Linear discharge   
        11
        |
        12
        |
        1
        <HTML>
        <L-PDF><Meta-XML>
        <引用本文> <批量引用> 7230666 false
        发布时间：2021-03-12
      • WANG Jinjun1,2 CHEN Youxin1,2 GAO Daqing 1 ZHOU Zhongzu1 YAN Huaihai1 XIA Jiawen1 1
        Vol. 32, Issue 5, (2009)
        摘要：A brief summary of H bridge non-isolated DC-DC converter and operation principles is presented in this paper.A small signal model of the ideal converter in continuous current mode is proposed and simulation results of the converter are given.The hardware structure of digital power supply controller based on TMS320F2808 MCU is introduced.  
        关键词：H bridge;DC-DC;BUCK;Small signal model;TMS320F2808   
        11
        |
        10
        |
        1
        <HTML>
        <L-PDF><Meta-XML>
        <引用本文> <批量引用> 7230502 false
        发布时间：2021-03-12
      0