最新刊期
      卷 0 ， 期 0 ， 2020
      • Zhang Yanzhong Jin Huijuan Xu Guiqin
        Issue 9, (1992)
        摘要：The microstructure of microcrystalline Fe73.1Cu1.2Nb3.2Si12.5B10 alloy has been examined by Mossbauer spectroscopy. The experimental results show that the microstructure of the alloy is composed of about 70% ordered phase Fe73+ySi25-y 26% amorphous phase as grain boundaries and a little paramagnetic phase. The y value in Fe75+ySi25-y has been preliminarily determined to be in the range of 5-7.  
          
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        发布时间：2021-04-09
      • Xiao Fengmei Li Shi
        Issue 9, (1992)
        摘要：A front - end data acquisition system based on STD BUS for Mossbauer spectroscopy is described. The system operates in both pulse height analysis and multichannel scaling mode and allows data pre -processing or filtering. With the system, many kinds of computer and / or microcomputer can easily read out Mossbauer experimental data on real time via a standard interface. The opening structure of the STD BUS managed by a Z80 processor helps to build up a flexible and expansible data acquisition system.  
          
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        发布时间：2021-04-09
      • Weng Shiqiang
        Issue 9, (1992)
        摘要：A new clustered segmentation method has been developed for PET. It is effective to reduce the PET transmission imaging time . By this approach the acquisition time of the transmission scan can be reduced from more than 15 min to 3 min only. The clinical studies as well as phantom tes.ts proved very successful. Futhermore,the method would be also useful to other kinds of images with high noise such as MR, SPECT etc.  
          
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        发布时间：2021-04-09
      • Huang Zhigao
        Issue 9, (1992)
        摘要：Mossbauer spectra of hydrided amorphous alloys Fe90-xCoxZr10（Ax）, Fe90-yCryZr10（By） （x=4, 10, 20;v=0, 4, 7, 13, 16, 20） and Fe-Cr-（Si, B） have been measured. For low hydriding time values, the average hyperfine field Bhf and isomer shift δis show a drastic increase which can mainly be related with the volume effect. For higher t values, an electron transfer effect can be responsible for the hyperfine parameter variation. The influence of hy-drogenation on magnetic anisotropy is also discussed.  
          
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        <引用本文> <批量引用> 8401722 false
        发布时间：2021-04-09
      • Wei Chenglian Li Daolun Hu Jinsheng Fan Qinmin Liu Yawen
        Issue 9, (1992)
        摘要：Scattered source lines can be used as an internal standard for determing the K value in gold ornements. The samples were excited by an annular 241Am source with an activity of 18. 5 GBq. The best measuring accuracy was 0. 29%.  
          
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        <引用本文> <批量引用> 8401758 false
        发布时间：2021-04-09
      • Zheng Jinshan Liu Jie Chen Xiaoxi
        Issue 9, (1992)
        摘要：It was indicated that when the mixtures, formed by accumulatively adding K2O, Cr2O3, MgO,CuO and SiO2 to a Fe2O3 in turn, were activated at 800cccccccccccccc in atmosphere for 5h, different reactions between a Fe2O3 and the added oxides were caused, and different compounds produced. The result will contribute to a better understanding of the role of various oxides as promoters and supports.  
          
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        <引用本文> <批量引用> 8401742 false
        发布时间：2021-04-09
      • Jin Mingzhi Liu Xuewu Liu Milan
        Issue 9, (1992)
        摘要：Mossbauer spectra of natural gadolinite and aeschynite were measured at 297K and 81K, respectively. The Mossbauer spectrum of gadolinite consists of one Fe3+ doublet and two Fe2+doublets, and the multiple Fe2+ doublets were attributed to the next nearest neighbour effect. The Mossbauer spectrum of aeschynite is composed of one Fe3+ doublet and one Fe2+ doublet,which is in agreement with the crystal structure determination result.  
          
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        发布时间：2021-04-09
      • Xiong Hongqi Huang Runsheng Lu Qingyou Xia Yuanfu Liu Rongchuan
        Issue 9, (1992)
        摘要：Small iron particles with oxide surfance layer were studied by Mossbauer spectroscopy at temperatures ranging from 5K to 300K. The Debye temperature of the oxide layer and the temperature dependence of f2/f1 were obtained, where f1 and f2 are the recoilless fractions for the inner α-iron core and the oxide layer respectively. Furthermore, the method of estimating thickness of the oxide layer was improved.  
          
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        发布时间：2021-04-09
      • Jin Jirong Jin Xin Zhang Yitong Xu Qigao Zhang Zhiping Zheng Songqi Liu Shengkang Yao Xixian
        Issue 9, (1992)
        摘要：The effect of slow-neutron irradiation at low fluence on high Tc superconductors was studied. It was found that this effect was nearly the same with the fast neutron irradiation reported by other research groups. The mechanism of the effect was discussed.  
          
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        <引用本文> <批量引用> 8401689 false
        发布时间：2021-04-09
      • Liu Changshi
        Issue 9, (1992)
        摘要：The Si/SiO2 system, prepared by reinforcement and non reinforcement craft against irradiation and irradiated with 60Co, was investigated with the depth dissection method of XPS. The experimental results indicate that 1) the interface of non reinforced samples was wider than that of reinforced ones ; 2) the interface of the samples with lower contentration of substrate impurity was narrower than that of the samples with higher concentration; 3) appearance of the highest density of transition state of silicon for irradiated samples had a lag behind non irradiated samples; 4) appeanance of the above highest density for reinforced samples was later than that for non reinforced samples; 5) appeaaranel of the above highest density for the samples with higher concentration of substrate impurity was earlier than that for the samples with lower concentration; and 6) the transition thickness of surplus oxygen was thiner than that of transition state of silicon. Finally, according to the experimental results a revised three layer model of Si/SiO2 was suggested.  
          
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        发布时间：2021-04-09
      • Zhao Xiaofeng Yang Fujia
        Issue 9, (1992)
        摘要：The basic principles of free electron laser (FED and its operation modes are presented. The state of the art is described for accelerator technology and laser systems. Some comparisons are made between FEL and conventional laser with regard to power capability, short-wavelength operation, and tunability. The application prospects of FEL are discussed.  
          
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        发布时间：2021-04-09
      • Zhao Yunlong
        Issue 9, (1992)
        摘要：Described are problems of system calibration and necessity of standardization in fission track dating （FTD） calibration, main points of recommendation on standardization of FTD calibration by the Fission Track Working Group of the I. U. G. S. Subcommission on Geochronology, and the future of standardization of FTD calibration.  
          
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        <引用本文> <批量引用> 8401678 false
        发布时间：2021-04-09
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