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Tritium is a fuel and the most mobile and significant radioactive sources for ITER. In the design of TBM tritium systems of China, the safety design of common chemistry engineering system and triti...

TiN+TiC+TiN multiple films are deposited on the surface of 1Cr18Ni9Ti stainless steel by ion-beam assisted deposition technology. The characteristics of films are tested by XPS, SEM and XRD, which ...

According to the requirements of the tritium related systems of the TBM (Test Blanket Module) for monitoring the on-line tritium concentration, a wide-range tritium-concentration detector has been developed to measure the tritium concentration in the range of 10{sup 4} Bq/ml - 5*10{sup 8} Bq/ml. This detector is combined with a low-memory helium ionization chamber. The weak current signal collected in the ionization chamber is converted to the voltage signal by an I-V converter. The minimum weak current which the detector could be measured is 10{sup -14} A. The performance of the background current and the current response linearity of the prototype have been tested. The test result indicates that the linear response of the current signal of the prototype without connecting the ionization chamber is good. The linear correlation coefficient is R{sup 2} = 0.998.

自上世纪50年代第一代玻璃闪烁材料开发以来, 玻璃闪烁材料在核物理、高能物理、工业探测(中子能谱测量、中子射线照相术及极端环境下α、β与γ射线的探测等)等领域发挥着越来越难以替代的作用. 中子探测用玻璃闪烁材料的研究集中于镧系离子(Ce 3+ 、Tb 3+ 、Pr 3+ 等)掺杂含6Li、10B等中子吸收截面较大核素的硅酸盐、磷酸盐、铝酸盐上. 本文由中子探测用玻璃闪烁材料的性能特点、发展历程与发光机理出发, 重点关注了含 6 Li硅酸盐玻璃、磷酸盐玻璃、氟氧玻璃及其它玻璃闪烁材料的制备方法、光学性能、荧光衰减时间及中子探测效率等性能研究, 并对玻璃闪烁材料的发展趋势及未来应用方向作出了展望.

Tritium diffusion and permeation in construct materials is one of the most important problems in fusion material research. For the tritium concentration evaluation within each sub-system of the fuel cycle of ITER, a finite volume computer program was developed for diffusion analysis of hydrogen isotopes in composite materials. The program calculates hydrogen isotope concentration distributions through composite materials such as tritium permeation barriers as function of the applied boundary conditions. The program can simulate hydrogen isotopes diffusion through single materials and composite materials in one-dimensional and can also make the output visualization. We look forward to making some comparison calculation for the present calculation with TMAP.

High density SiC ceramics with 4 wt.% (in mass) and without Al 2 O 3 as sintering additive were fabricated by nano-SiC as raw materials under different technical condition (1000–1300 °C, 4.0–4.5 GPa, 15–35 min) using China-type twain face anvils apparatus. The effect of sintering parameters on the mechanical property of SiC ceramics was studied. The sintered SiC was characterized by XRD, SEM, EDS and micro-hardness instruments. The results indicated that pure SiC could be sintered to high density (SiC sintered at the condition of 4.5 GPa/1250 °C/35 min could reach 96% of its theory density) by ultra-high pressure technique, and Al 2 O 3 is a kind of effective sintering additive, SiC doping with only 4% Al 2 O 3 could be sintered to full density by ultra-high pressure technique. The grain size was kept in nano-scale, its crystal lattice shrinkage was about 0.45%, while β-SiC has not changed. The micro-hardness and density were increased with increasing sintering temperature, pressure and holding time. The ultra-high pressure method could effectively lower the sintering temperature, shorten the sintering time and reducing the usage of sintering additive. Under 4.5 GPa the lowest sintering temperature was 1300 °C, which was above 600 °C lower than that for conventional liquid-phase sintering and its density is much higher.