Liquid metals-such as lead (Pb) or lead-bismuth (PbBi) are used as reactor core coolants for accelerator driven systems (ADS) proposed for high-level radioactive waste transmutation. Compatibility of steels with liquid PbBi is a key problem because steels are attacked by dissolution of the components in PbBi, so it has to form a stable coating on steel surface. There are many methods to prepare anti-corrosion coatings on steel, such as hot dipping, pack cementation, plasma spaying, and physical vapor deposition (PVD). Compared with other methods, the PVD method is easy to control the thickness of the coating and the obtained coatings are dense which is crucial to the anti-corrosion ability of the coatings. In this letter, PVD aluminum coatings are developed on the surface of T91 steel and different heat-treatment atmosphere is used to adjust the microstructure, aluminum content, and the phase of the coatings. It is found that the coatings have good adherence ability with steel. The aluminum content and the phase of the coating can be adjusted by the heat-treatment atmosphere. Corrosion tests are performed in oxygen-saturated liquid PbBi at 550 oC for 1 000 h, the phase and composition of the coating do not change drastically. All the results indicate that the PVD is a useful method to prepare coatings on the surface of steel used in liquid PbBi.

临床研究表明波长308 nm准分子激光治疗白癜风皮肤病效果明显。治疗效果与病人的性别、年龄、病程没有明显关联, 但与皮肤类型、皮损部位、治疗频度和疗程等有明显关联。在一定剂量范围内随治疗剂量和治疗时间增加治疗效果越来越明显, 呈线性变化。而皮损部位的影响, 疗效从明显到不明显的顺序是: 面部, 颈部和头皮, 生殖器, 四肢, 躯干, 手脚或肢端关节。皮肤类型对治疗效果影响明显。另外, 在一定的观察时间内发现308 nm准分子激光疗效明显高于NB UVB。