最新刊期
      期 1 ， 2000
      • TIAN Jun,QI Shangkui,YANG Xiaohong,JIN Qixin,WANG Qizu,XUE Qunji
        Vol. 18, Issue 1, Pages: 52-56(2000)
        摘要：La0.96Tb0.01Dy0.03BO3 luminophor is sythetized using high temperature solid phase. The luminescence of La0.96Tb0.01Dy0.03BO3 by γ-ray irradiation was briefly studied. Tb3+、Dy3+ 4d electron binding energy in La0.96Tb0.01Dy0.03BO3 was close to 161.0eV. and Tb3+、Dy3+ 4d binding energy peak areas changed with the change of irradiation doses. At 1.5×104Gy dose, La0.96Tb0.01Dy0.03BO3 has the maxim value of luminous intensity.  
        关键词：La0.96Tb0.01Dy0.03BO3;γ-ray irradiation;Luminescence   
        2
        |
        0
        |
        2
        <HTML>
        <L-PDF><Meta-XML>
        <引用本文> <批量引用> 35964320 false
        发布时间：2023-04-07
      • WU Lijun,Tom K. Hei,G Randers-Pehrson,YU Zengliang
        Vol. 18, Issue 1, Pages: 57-62(2000)
        摘要：The key to doing microbeam studies is to precisely control and accurately deliver the counted number of particles to a target position. By studying the Columbia University single particle microbeam, this report shows that it can irradiate the targets with a defined number of α particles, and the collimation of beam size according to the resolution of 20 α particles is ~3~4µm which is better than the designed index. Besides, it can be used for cytoplasmic irradiation with a hitting probability nearly 90% and the odds to hitting nucleus during this process is less than 0.8% for most doses. Radiological studies using this facility found that only 20% of irradiated cells were killed by a single α particle, and the dose response curve for nuclear irradiation with exact number of particles was not significantly different from the curve obtained using average particle traversals of broad-field exposure. The mutation data in microbeam studies provide the first demonstration that a single α particle traversal induced mutations in AL cells at a level 3X greater than the background value, and the mutation yield increased in a dose dependent manner. This results was quite different from the data obtained from broad field exposure which showed that at high doses, the mutation frequencies decreased.  
        关键词：Microbeam;Nucleus or cytoplasmic irradiation;Accuracy;Radiological effect   
        2
        |
        0
        |
        2
        <HTML>
        <L-PDF><Meta-XML>
        <引用本文> <批量引用> 35964319 false
        发布时间：2023-04-07
      • DING Guirong,GUO Guozhen,TIAN Furong,WANG Jin,ZHANG Liyan,GUO Yao
        Vol. 18, Issue 1, Pages: 63-67(2000)
        摘要：To discuse the changes of apoptosis level in small bowl and colon of mice after γ-ray irradiation. The mice were irradiated with different doses (1, 6, 12Gy). The incidence of apoptosis in small bowl and colon were observed at diffifent time (6, 12, 24h)after irradiation using morphological method. The results indicate that there were apoptosis in small bowle of normal mice, the number of apoptotic cell was 0.038±0.059 per whole crypt. No apoptosis was observed in colon of normal mice and irradiated mice; The incidence of apopotosis significantly increased in small bowl after different doses of irradiation (p <0.05). The apoptosis peak appeared at 12, 24, 6h after 1, 6, 12Gy irradiation; The incidence of apoptosis was higher in small bowl than that of colon after different doses of irradiation and at different time after irradiation. From the results we propose that the radiation-damaged cells might be more effectively removed in small bowle than in colon after irradiation. Radiation-damaged cells may tend to remain in colon and related to later tumorigenesis.  
        关键词：Radiation;Small bowl;Colon;Apoptosis;Mice   
        2
        |
        0
        |
        3
        <HTML>
        <L-PDF><Meta-XML>
        <引用本文> <批量引用> 35964409 false
        发布时间：2023-04-07
      • YANG Zhongtian,Yosuke Morita,Toshiaki Yagi,Tadao Seguchi
        Vol. 18, Issue 1, Pages: 68-72(2000)
        摘要：Oxygen consumption for PVC、 EPR and CSM as the cable insulation materials after irradiation and thermal aging were measured by using gas chromatograph in order to study the lifetime estimation. Kinetic analysis of experiment data was made. It is found that thermal oxidative reaction is a first-order reaction under the experiment condition in this work. Rate constants were obtained. Comparison with the theoretical calculated data according to Arrhenius equation was also made. It is thought that the simplified Arrhenius equation is not appropriate as the model for lifetime estimation.  
        关键词：Polyvinyl chloride;Ethylene-propylene copolymer;Chlorosulfonated polyethylene;Thermal oxidative degradation;Kinetic analysis;Gas chromatograph;γ-irradiation   
        2
        |
        0
        |
        0
        <HTML>
        <L-PDF><Meta-XML>
        <引用本文> <批量引用> 35964383 false
        发布时间：2023-04-07
      • PIAO Chunji,ZHANG Haiying,YIN Hongshu,WANG Xianli
        Vol. 18, Issue 1, Pages: 77-79(2000)
        摘要：In order to probe into the effect of hormesis of low dose of radiation and low dose of bleomcin A5(BLMA5) on mice, we investigated the growth of tumors implanted in Kunming mice, which had been treated with these two factors 6h before tumor implantation. The results showed that the tumor incidence and tumor growth of the treated group were significantly lower than those of control group (p <0.05). It was proved that both low dose of radiation and low dose of BLMA5 can induce hormesis, i.e., enhance defensive function of animal bodies and inhibit the growth of implanted tumors.  
        关键词：Low dose of radiation;Low dose of bleomycin A5;Tumor incidence;Hormesis   
        2
        |
        0
        |
        2
        <HTML>
        <L-PDF><Meta-XML>
        <引用本文> <批量引用> 35964399 false
        发布时间：2023-04-07
      0