最新刊期
      卷 0 ， 期 0 ， 2020
      • LIU Kai1,2 XUE Song1 LU Qipeng3 PENG Zhongqi3 WU Kun1,2 CHEN Jiahua1 WANG Yong1 GONG Zhihua1,2 1
        Vol. 32, Issue 12, (2009)
        摘要：In establishing the soft X-ray microscopy beamline at SSRF,angular repeatabilities of the plane mirror and the grating should be better than 0.43" to achieve the PGM’s energy resolution.We designed an autocollimator system to measure the plane mirror and the grating.Test results show that angular repeatabilities of the plane mirror and the grating are measured at 0.166" and 0.149",respectively,and the resolution is 0.03",satisfying the technical requirements of the plane mirror and the grating for the angular repeatability and resolution.The angle repeatability of the grating switch is very good,too.  
        关键词：Variable included angle plane-grating monochromator;Photoelectric autocollimator;Angle repeatability;Measurement   
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        发布时间：2021-03-12
      • YI Rongqing1 CUI Yanli1 DU Huabing1 ZHAO Yidong2 CUI Mingqi2 ZHENG Lei2 1
        Vol. 32, Issue 12, (2009)
        摘要：Using a detector in an ionization chamber of large cavity,one is able to measure gas absorption directly,with reduced grads of gas density distribution,so as to avoid uncertainties due to air pressure instability,window absorption and size of the window film.In this paper,various factors causing uncertainties in the X-ray intensity measurement were analyzed.Uncertainty of the X-ray ionization standard detector is less than 5%.  
        关键词：Ionization;X-ray standard detector;Ionization section   
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        发布时间：2021-03-12
      • WANG Baoliang1 PEI Shilun2 ZHAO Minghua1 HOU Mi2 1
        Vol. 32, Issue 12, (2009)
        摘要：The Shanghai Synchrotron Radiation Facility (SSRF) adopts a 2998 MHz linac,which is in similar structure of the SLAC linac,but the dimensions are slightly different,hence the need of calculating the coupler dimensions.This paper focused on the simulation of the coupler.The simulation used three–frequency mode just like testing the accelerator in the laboratory.The physics design of 2998 MHz coupler was carried out using the Superfish code with two-dimensional finite difference method,and the HFSS code with the three-dimensional finite element method.The simulation result is greatly agreement with the experiment test.  
        关键词：Accelerator;Coupler;Three-frequency mode;Physics design   
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        发布时间：2021-03-12
      • LIANG Xianqing1,2 ZHONG Jun1 ZHAO Ting1 YAO Peng1 IBRAHIM KUrash1 QIAN Haijie1 WU Ziyu1,2 1
        Vol. 32, Issue 12, (2009)
        摘要：A systematic characterization of single-walled carbon nanotubes (SWCNTs) after successive purification steps,including air oxidation at 350℃,hydrochloric acid etching and 600℃ annealing in Ar,have been performed combining X-ray absorption near-edge structure (XANES) and X-ray photoelectron spectroscopy (XPS).The results indicated that the modification degree of SWCNTs increased after the purification procedures,but decreased significantly by annealing in Ar.It also showed that the SWCNTs could bond with chlorine atoms during the hydrochloric acid etching and suggested this modification may be importance for the applications.  
        关键词：Single-walled carbon nanotubes;X-ray absorption near-edge structure;Photoelectron spectroscopy;Modification   
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        发布时间：2021-03-12
      • LU Ying HU Shuxin MAI Zhenhong LI Ming
        Vol. 32, Issue 12, (2009)
        摘要：Synchrotron radiation X-ray diffraction study was performed on short chain DNA/lipid multilayers prepared by drop-casting solutions of DNA and lipid mixtures onto solid surfaces.DOTAP and DOPC mixtures were used in the study with ΦDOTAP denoting the DOTAP content.The DNA contents are such that the systems are at their isoelectric point.The multilayers are formed via self-assembly during evaporation of the solvent.The results indicate that the short chain DNA molecules are embedded randomly in the hydrophilic headgroup regions of the lipid bilayers when ΦDOTAP≤50%,while the DNA molecules form a closely packaged layer inside each lipid bilayers when ΦDOTAP≥90%.The DNA-poor phase and DNA-rich phase coexist at intermediate DNA contents.The bilayers are distorted in the DNA-poor phase,while they are well-ordered in the DNA-rich phase.The phase transition is driven by the lowering of the interfacial energy.  
        关键词：Lipoplexes;Lipids;DNA;Multilayers;X-ray diffraction   
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        发布时间：2021-03-12
      • LIU Xiaoxu1,2 YIN Jinghua1,3 YAN Kai2 CHENG Weidong4 WU Zhonghua4 1
        Vol. 32, Issue 12, (2009)
        摘要：Inorganic nanohybrid polyimide (PI) has wide applications in electric and electronics for its outstanding insulating,mechanical and heat-resistance properties.Al2O3/PI nanohybrid films of 100CR (Dupont),with excellent corona-resistance,were characterized by synchrotron radiation small angle X-ray scattering (SAXS) and transmission electric microscopy (TEM).The results show that the inorganic particles are 4–7 nm in size.The interface between nanoparticles and matrix is sharp.Fractal dimension of the film is 2.48.  
        关键词：SAXS;Nanohybrid;Polyimide;Fractal dimension   
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        发布时间：2021-03-12
      • YI Taimin XING Pifeng LI Chaoyang XIE Jun ZHENG Fengcheng LI Guorong
        Vol. 32, Issue 12, (2009)
        摘要：Techniques of preparing metal uranium films and their application were discussed,including mechanical polishing,mechanical rolling,evaporating in high vacuum,pulse laser deposition and magnetron sputtering deposition.Technological parameter and thickness,surface quality,composition,grain structures of the uranium films were discussed in detail.The monitors of the uranium film thickness and deposition rate were briefly introduced.  
        关键词：Metal uranium film;Evaporating in high vacuum;Magnetron sputtering deposition   
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        发布时间：2021-03-12
      • DENG Lei YANG Yaxin LU Cunheng LIU Qingcheng CHEN Yue YAN Zheng FANG Lei
        Vol. 32, Issue 12, (2009)
        摘要：Based on the theory of airborne γ-ray field,we propose a method was for determining boundary of radioactive plume.Under the medium exchange principle,mine-body models were used to simulate plume on the ground by air-sand exchange.The results show that,after the medium exchange,difference between the simulated and theoretical plume widths is small,with the relative deviations ranging from 6.4% to 8.9% for exceptional half width in the air (2z) from 410 m to 602 m.The method can be applied to boundary determination in airborne survey.  
        关键词：Radioactive matter;Z measuring plate;EPZ;Medium reciprocity principle;Plume   
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        发布时间：2021-03-12
      • YANG Lei LIU Yibao LIU Yujuan
        Vol. 32, Issue 12, (2009)
        摘要：A plant growth simulation algorithm was proposed for optimizing source pencil deployment for a 60Co irradiator.A method used to evaluate the calculation results was presented with the objective function defined by relative standard deviation of the exposure rate at the reference points,and the method to transform two kinds of control variables,i.e.,position coordinates xj and yj of source pencils in the source plaque,into proper integer variables was also analyzed and solved.The results show that the plant growth simulation algorithm,which possesses both random and directional search mechanism,has good global search ability and can be used conveniently.The results are affected a little by initial conditions,and improve the uniformity in the irradiation fields.It creates a dependable field for the optimization of source bars arrangement at irradiation facility.  
        关键词：Plant growth simulation algorithm;Gamma-ray irradiator;Source pencil deployment;Relative standard deviation   
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        发布时间：2021-03-12
      • ZHANG Songbai1,2 WU Jun2 1
        Vol. 32, Issue 12, (2009)
        摘要：The active method of delayed neutron is an effectively verification means for monitoring the uranium material.A model was established to simulate the D-T neutron source inducing uranium shell of the same mass but in different 235U enrichments,and the response of BF3 detector for the delayed neutrons from the uranium shell.The method to determine the enrichment of uranium was validated on the condition that a special uranium shell model with the inducing of D-T neutrons.  
        关键词：Delayed neutron;Uranium;Enrichment   
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        发布时间：2021-03-12
      • TANG Fangdong1 HE Linfeng1 ZHANG Junkui2 TANG Bin2 1
        Vol. 32, Issue 12, (2009)
        摘要：A standard radon chamber is used as reference standard for calibrating monitors of radon concentration.The radon concentrations can be calculated by radon yield rate of radioactive source,radon-filling time,the decay constant and radon adsorption/leak ratio.It can also be measured by the standard radon monitor,but uncertainties of the measured radon concentration should be evaluated scientifically and rationally.In this paper,sources of the uncertainties were analyzed by two measuring methods of radon concentration,and evaluation methods of the uncertainties were introduced and discussed.The experiment result shows that the uncertainty evaluation method using a standard radon monitor is better than calculation of a radon radioactive source.  
        关键词：Uncertainty;Standard radon chamber;Radon concentration;Traceability   
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        发布时间：2021-03-12
      • LONG Yindong1,2 QIAO Weimin1 LIN Feiyu1,2 JING Lan1 1
        Vol. 32, Issue 12, (2009)
        摘要：The magnetic control of a synchrotron is a high precision real time system.With the development of digital processing,the HIRFL-CSR project (Cooler Storage Ring of the Heavy Ion Research Facility in Lanzhou) has higher requirements on floating multiplier’s speed and used-resource.In this paper,we report the improved floating multiplier realized by the VHDL and the Booth algorithm,based on the tree-structure consisting of the 4-2 and 3-2 compressors.It takes the EP3C25F256 as the hardware environment to get the timing-emulate and function-emulate.Comparing with other designs,this floating multiplier has better in correction and speed.  
        关键词：LSI;Floating number;Float-number-multiplier;Specification   
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        发布时间：2021-03-12
      • YAO Zhibin HE Baoping ZHANG Fengqi GUO Hongxia LUO Yinhong WANG Yuanming ZHANG Keying
        Vol. 32, Issue 12, (2009)
        摘要：In order to study testing methods and find sensitive parameters in total dose effects on SRAM-based FPGA,XC2S100 chips were irradiated by 60Co γ-rays and tested with two test circuit designs.By analyzing the experimental results,the test flow of configuration RAM and bock RAM was given,and the most sensitive parameter was obtained.The results will be a solid foundation for establishing test specification and evaluation methods of total dose effects on SRAM-based FPGAs.  
        关键词：FPGA;Radiation effects;Total dose effects   
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        发布时间：2021-03-12
      • ZHAI Hongyan1 YANG Jicheng2 SHENG Weihua2 XIE Yufeng2 FA Yihua1 SU Chenghai1 1
        Vol. 32, Issue 12, (2009)
        摘要：This work is to investigate the combined tumor-suppression effect of Adenovirus-mediated human ING4 (Ad-hING4) and 125I seed on human pancreatic cancer xenograft and the possible mechanisms.Ad-hING4 recombinant adenovirus vector was transected into QBI-293A cells and high titre adenovirus was obtained.Subcutaneous tumor models were established with 25 nude mice with human pancreatic cancer cell line PANC-1.They were randomly divided into 5 groups: PBS control group,Ad carrier group,125I seed brachytherapy group,Ad-hING4 gene treatment group,combined 125I seed and Ad-hING4 group.The tumor volumes were measured every 5 days after treatment,and were sacrificed on the 20th day.The tumors were measured and weighed to determine the ratio of tumor-suppression and Jin-Shi q value.Morphological changes of tumor cells,the tissue injury and apoptotic index AI were examined on pathological sections.MVD,Survivin and Caspase3 were tested in immunohistochemistry.The results show that the tumor-suppressive ratio of the 125I seed group,Ad-hING4 group,combined treatment group were,respectively,34.19%(P < 0.01),31.50%(P < 0.01),and 67.15% (P < 0.01) which was markedly higher than other two groups (P < 0.01).The pathological examination found degenerative necrosis at the site was nearby the seed but the living tumor cell still presented faraway from the seed.AI and Caspase3 positive cells in the treatment groups were higher than PBS group significantly (P < 0.05),and the combined treatment group was higher than other two treatment groups significantly (P < 0.01).MVD and Survivin positive cells in the treatment groups were lower than PBS group significantly (P < 0.05),and the combined treatment group was lower than other 2 treatment groups significantly (P < 0.01),too.There was no significant difference between Ad group and PBS group in every detection index (P > 0.05).It can be concluded that 125I seed and Ad-hING4 inhibit the growth of PANC-1 pancreatic cancer on nude mice significantly.These indicate a synergy of the combined treatments in tumor-suppression and Ad-hING4 is a promising novel radiosensitizer.The mechanisms of tumor-suppressive may be multi-pathways such as down-regulation the expression of Survivin and up-regulation the expression of Caspase3 to induce apoptosis and inhibit angiogenesis.  
        关键词：125I seed;Brachytherapy;hING4;Pancreatic neoplasms;Nude mice;Gene therapy;Radiosensitizer;Mechanisms   
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        发布时间：2021-03-12
      • ZHU Ruisen LUO Qiong LU Hankui CHEN Libo LUO Quanyong
        Vol. 32, Issue 12, (2009)
        摘要：Characteristic images of 99mTc-MDP bone scintigraphy in patients with metabolic bone diseases (MBD) were analyzed and compared,in an attempt to improve the capability of differential diagnosis in this aspect.A total of 142 cases,clinically confirmed as (MBD),were categorized into six groups: hyperparathyroidism (117),renal osteodystrophy (4),Paget’s disease (16),hypophosphatemic osteomalacia (2),Albers-Schonberg disease ( 2) ,and Brittle bone disease (1).They were diagnosed clinically or pathologically,and scanned with 99mTc-MDP bone scintegraphy,from which the 142 MBD cases were classified into 4 types.The cases of Type I had increased amount of 99mTc-MDP uptake in whole body bones,including hyperparathyroidism,Albers-Schonberg disease,brittle bone disease and renal osteodystrophy.The cases of Type II had high uptake of 99mTc-MDP in local region of bones,including paget’s disease,hypophosphatemic osteomalacia and hyperparathyroidism.A Type I case with pathological fracture or secondary osteopathy was classified as Type III.Type IV cases were in early stage of hyperparathyroidism,with normal bone scan image.Analysis of the characteristics of 99mTc-MDP bone scintigraphic findings (locations,morphology and intensities) in patients with MBD may be helpful in the differential diagnosis of MBD,in association with the patient’s history and X-ray data altogether.  
        关键词：Metabolic bone disease;Bone scintigraphy;99mTc-MDP   
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        发布时间：2021-03-12
      • SUN Punan
        Vol. 32, Issue 12, (2009)
        摘要：A storage-type density meter for oil logging has been developed.It constitutes of a 137Cs source,a NaI scintillation detector,a pulse amplifier,a date storage circuit,a high voltage power supply and a Li ion battery,being integrated into a stainless steel container of Φ 60 mm × 1300 mm.Unlike density meters in current uses,this type of density meter goes into an oil well without an armored cable.Density data acquired in the well are stored for data analysis with a PC in laboratory.The density distribution derived from oil well can be a guide for oil exploration.Logging of the density meter can be done with only one crane,for a continuous logging of up to 15 days.  
        关键词：γ-ray;NaI scintillation detector;Data storage in well;Nuclear density meter   
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        发布时间：2021-03-12
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