Study of shielding design for SANS at CSNS

The small angle neutron scattering (SANS) instrument is presently being constructed at Chinese Spallation Neutron Source (CSNS) in China, and the biological shielding design is needed to prevent the instrument from causing excessive dose rates in accessible locations. In this paper, the study of shielding design for SANS that relies on Monte Carlo simulation is introduced. Beam line shielding calculations are performed considering both scenarios of closed versus open T0 chopper. The basic design scheme of the beam stop is discussed. The size of the T0 chopper rotor is also estimated.     

中国散裂中子源小角散射谱仪

正作为中国散裂中子源(CSNS)首批建设的三套谱仪之一,小角散射谱仪用于探测物质体系在1~100 nm尺度内的微观和介观结构。它的实验应用范围将涵盖化学、物理、生物、材料、地质等广泛学科,服务于国家能源、环境、生物和新材料等诸多高科技研发领域。中国散裂中子源小角散射谱仪建成后,能为图1所示例的诸多科学探索与技术研发工作,提供必需的实验方法及其技术手段。一、中子散射技术的缘起与现状     

Atomic pair distribution function method development at the Shanghai Synchrotron Radiation Facility

The atomic pair distribution function(PDF) reveals the interatomic distance in a material directly in real-space. It is a very powerful method to characterize the local structure of materials. With the help of the third generation synchrotron facility and spallation neutron source worldwide, the PDF method has developed quickly both experimentally and theoretically in recent years. Recently this method was successfully implemented at the Shanghai Synchrotron Radiation Facility(SSRF). The data quality is very high and this ensures the applicability of the method to study the subtle structural changes in complex materials. In this article, we introduce in detail this new method and show some experimental data we collected.     

液体聚丁二烯原位涂层研究——Ⅰ.LPB在碳钢表面的成膜层及其缓蚀性能

采用乳化或接枝共聚合引进—COOH,—OH亲水基团后的液体聚丁二烯,溶于模拟碳钢酸洗液中,在过氧化物与碳钢腐蚀产物所组成的氧化还原引发体系的作用下,于“金/溶”界面聚合成膜。失重试验结果表明膜层的缓蚀性能取决于乳液体系的成份,浓度和温度等。文中探讨了这一聚合作用的机理。     

China Spallation Neutron Source - an overview of application prospects

The China Spallation Neutron Source (CSNS) is an accelerator-based multidisciplinary user facility to be constructed in Dongguan, Guangdong, China. The CSNS complex consists of an H^－ linear accelerator, a rapid cycling synchrotron accelerating the beam to 1.6 GeV, a solid-tungsten target station, and instruments for spallation neutron applications. The facility operates at 25 Hz repetition rate with an initial design beam power of 120 kW and is