分类: 核科学技术 >> 粒子加速器 提交时间: 2023-06-18 合作期刊: 《Nuclear Science and Techniques》
摘要: A proton therapy system is a large medical device to treat tumors. Its gantry is of large structure and high precision. A new half-gantry was designed in the Shanghai Advanced Proton Therapy (SAPT) project. In this paper, the weight of gantry in design is reduced significantly by size and structure optimizations, to improve its cost-effectiveness, while guaranteeing the functions and precision. The processes of physics optimization, empirical design optimization, topological optimization and size optimization, together with factors of consideration, are described. The gantry weight is reduced by 30%, with the same precision.
分类: 化学 >> 物理化学 提交时间: 2017-11-05 合作期刊: 《结构化学》
摘要: In order to discover the novel anti-tumor agents, a series of 2-[(pyridin-2-yl)methylthio]-1H-benzimidazole derivatives were designed and synthesized, and the structures were characterized by IR, MS, and proton NMR. 2-[(3,4-Dimethoxypyridin-2-yl)methylthio]-1H-benzimidazole was investigated with X-ray crystallography, and the molecule is in orthorhombic system, space group P212121, with a = 9.1828(16), b = 11.625(2), c = 13.463(2) � Z = 4, R = 0.0231 and wR = 0.0596. The antitumor activities of target compounds were evaluated against human liver cancer cell line HepG2, and human liver normal cell line HL7702 using MTT assay. The target compounds have demonstrated weak or moderate anti-tumor activity against HepG2, while all the target compounds exhibit no cytotoxic effects on HL7702.