Microstructural change of YBaCuO film/YSZ substrate with and without proton irradiation has been studied by scanning electron microscope and X- ray diffraction techniques. Structural analysis has shown that conversion from tetragonal to orthorhombic phases, reduction of nonsuperconducting phase and preferential rearrangement of crystal grains are all favorable to the improvement of superconductivity in the YBaCuO film supported by YSZ substrate by proton beam bombardment.
Vol.1, No.3
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1990
3
Research article 01 Aug 1990
Wang Guanghou，Luo Chenglin，Pan Guoqiang，Yan Shiqian，Han Min，Yang Senzu，Li Yuan，Ji Zhengming，Sun Zhijian，Wu Peiheng
keyword：YBaCuO superconducting film；Proton irradiation；Scanning electron microscope；X-ray diffraction；Conversion of phases；
Research article 01 Aug 1990
Ji Chengzhou，P. Wang，Shan Jinan，Zheng Dongdong
Upon heating, Mn atoms implanted into Na+- beta- alumina diffuse inwards and outwards with an activation energy of 0.96 eV, and substitute for Al3+ in the spinel layers of the crystal. For specimens annealed at 900℃, the optical absorption shows remarkable change in 190nm-400nm wavelength region. They fluoresce brightly green and a well- defined peak (at 525 nm) has been found in the radiative spectra.
keyword：Beta- alumina；Diffusion；Luminescence；Ion implantation；
Research article 01 Aug 1990
Zhao Guoqing，Ren Yuehua，Zhou Zhuying，Tang Guohun，Tang Jiayong
An experimental apparatus for studies of MeV ion beam modification of materials has been established on a 3 MV tandem accelerator at Fudan university. A system of X-Y electrostatic scanning implantation of MeV heavy ions and in situ Rutherford backscattering analysis was included in it. The uniformity of scanning implantation was checked by the RBS measurement of a Si wafer implanted with 1 MeV Au+ ions. MeV ion beam mixing of Au/Si, Au/Ge and Ag/Si systems was preliminarily studied. The samples were irradiated by certain fluences of 1 MeV Ag+ ions at room temperature. The mixed layers were analyzed in situ using the glancing RBS technique with 2 MeV 4He+ ions. For Au/Si system, a uniformly mixed layer with a defined composition is obtained, and the intermixing is much less for Ag/Si system than for Au/Si system.
keyword：MeV Ag+ ions；Atomic mixing；Au/Si, Au/Ge and Ag/Si systems；
Research article 01 Aug 1990
Zhang Ruju，Liu Hongtao，Guo Zhiyu，Li Kun
A single and dual parameter data acquisition, ion beam measurements and control system for accelerator mass spectrometry is described. The system hardware has been constructed with the advantage of the lower cost and higher reliability. It is provided with varieties of functions such as selecting acquisition mode carrying out the multiple display, analyzing data and especially viewing isometric spectrum at different directions. It can also be used for ordinary nuclear spectrum system.
keyword：Accelerator mass spectrometry (AMS)；Single and dual parameter data acquisition；Nuclear spectrum；Isometric display；Data analysis；
Research article 01 Aug 1990
Liu Huizhen，Sheng Kanglong，Zhu Dezhang，Yang Guohua，Zhu Fuying，Cao Jianqing，Tang Lijun
A combined PIXE- RBS channeling measurement system to examine III- V compound semiconductors has been established. Preliminary results on studying Si+ and Te+ implanted GaAs have been presented and discussed.
keyword：Ion implantation；Compound semiconductor；GaAs；PIXE- channeling technique；
Research article 01 Aug 1990
Xia Zongqin
A new curve fitting method with its mathematical models derived from the mass action law is presented which is applicable to several in vitro radioassays including RIA and RBA. Experiments revealed that the robustness of this method is better than the conventional methods like Woolf plot in RBA and 4- parameter logistic plot in RIA. However, the robustness of this method is only relative: in some cases of RIA and RBA, the bias of the results may still be too large to be acceptable. Further improvement is expected to be studied.
keyword：Vitro radioassays；Curve fitting；Mathematical models；Mass action law；
Research article 01 Aug 1990
Huang Peihua，Jin Sizhao，Liang Youren，Lu Zhongjia，Zheng Lizhen，Yuan Zhenxin，Cai Bingxi，Fang Zhaomeng
In this paper, we used ESR dating method to measure the accumulative dose of the fossil teeth samples, which are contemporaneous with the Peking- Man. The internal annual dose rate of samples are got by neutron activation analysis and the environmental annual dose rate by highly sensitive TL dosimeters to be embedded in cave deposits in the site. The results of ESR dating are corresponded with the dating results obtained by U- series, FT, TL and paleomagnetic stratigraphical methods on the 3rd, 4th, 7th and 10th layers. Calculation of using different models, the close- equilibrium model, the linear uranium accumulation model and radon loss- linear uranium accumulation model, for travertine, deer teeth and rhinoceros tooth, we obtained the age of the First Peking- Man in the 11th layer is 578 ka and gave ages of other layers, from the 1st to the 13th layer in Peking- Man site.
keyword：ESR dating；Peking- Man'；s age；
Research article 01 Aug 1990
Guo Zili，Zhu Jingrong，Wei Ziping，Zhou Ruiju，Zhang Yulong
The syntheses of N - Methyl- 14C benzyl amine and N - Methyl- 14C benzyl nitrosamine are reported. Specific activities were approximately 920 MBq/mmol. Chemical and radiochemical purity checked by HPLC were more than 95%.
keyword：N - Methyl- 14C benzyl amine；N - Methyl-14 benzyl nitrosamine；Trifluoroacetamide；14C - Labelled compounds；
Research article 01 Aug 1990
Yu Fengqiao，Zhou Baoguo，Sun Ankang，Li Zuoqian
In this article, a Bi4π counting method comprised of Bi4π counter and a new fundamental measurement method was described, which can measures rather more radionuclides and can achieve accuracy of 0.03% to 0.06% (1σ), in principle. The correctness of this method is demonstrated by measurements of 60Co sources which results of activities compared with 4π β-γ coincident method are in agreement within the measurement errors, and it is readily achieved to accuracy of 0.2%. Finally, the range of the applications for this Bi4π counting method among one hundred or more important radionuclides is also discussed.
keyword：Activity；Bi4π method；Measurement；4π Counter；
Research article 01 Aug 1990
Jin Weiqiao，Chen Shijie，Mo Suzhen，Fan Peifang，Le Min，Zhang Hao，Li Yonghe，He Jiewei
α2- macroglobulin (α 2M) could stimulate the regeneration of thymic and bone marrow cells in rats received γ - irradiation, but there was very few reports concerning its mechanism. Wistar rats were irradiated by 16Co at 7 Gy, 8.5 Gy, 15 Gy total body doses. Blood plasma and some tissue's extracts were collected α 2M level. a M activity and cathepsin D activity, malonaldehyde level were determined by radioimmunoassay, modified Schidlow's method, Barrett's method and Ohkawa's method respectively.
keyword：Alpha- 2- macroglobulin；Cathepsin D；Malonaldehyde；radiation；Rat；
