Beam dynamics studies on BEPC-Ⅱ storage rings at the commissioning stage

During the 1 st and 2 nd stages of the commissioning of the upgrade project of the Beijing Electron Positron Collider (BEPCⅡ), which started on Nov. 12, 2006 and Oct. 24, 2007, respectively, we got the luminosity one tenth of its design value, provided beams to synchrotron radiation users for about 4 months, and studied beam dynamics as well. In this paper, some beam dynamics studies on the storage rings and their preliminary results are given.     

基于鞘脂组学技术探究布洛芬对斑马鱼脑组织的立体选择性影响

以斑马鱼成鱼为研究对象,借助于鞘脂组学技术,探究了一种新型手性环境污染物布洛芬对斑马鱼脑组织中鞘脂含量的影响。建立了超高效液相色谱-三重四极杆-线性离子阱复合质谱检测斑马鱼成鱼脑组织中46种鞘脂的定量方法。借助于该方法对经布洛芬外消旋体及对映体暴露后的斑马鱼脑组织中的46种鞘脂进行了定量分析,通过考察主成分分析（PCA）、正交偏最小二乘法分析（OPLS-DA）及显著性差异分析（P）筛选出差异代谢物。同时,结合组间差异分析的结果可知,环境水平的布洛芬会导致斑马鱼脑组织中鞘脂代谢发生紊乱,且布洛芬的对映体之间存在立体选择性毒性。     

高分子材料的微波辅助合成研究进展

微波加热以其省时、高效、清洁环保的显著优势而使微波辅助合成成为一种广受欢迎的合成技术。高分子材料的传统合成反应时间长、耗能大。将微波辐射应用于高分子材料的合成可缩短反应时间、降低反应能耗,已成为有机合成领域的研究热点。本文简要综述了微波辅助合成技术在工程材料高分子聚酰胺、聚酰亚胺、聚丙烯酸苄基酯以及在医用功能高分子、吸附功能高分子、导电功能高分子和光学功能高分子合成中的研究进展,并展望了微波辅助合成在高分子材料合成中的发展前景。     

Beam-loss driven injection optimization for CSNS/RCS

This paper summarizes the painting injection optimization for the Chinese Spallation Neutron Source （CSNS） ring. This optimization focuses on two main design goals： the lower beam loss and a spacecharge tune shift low enough to avoid strong resonances. Finally, the 3-D particle tracking is performed and we get some important results about the beam properties and beam loss.     

ATPF—a dedicated proton therapy facility

A proton therapy facility based on a linac injector and a slow-cycling synchrotron is proposed. To obtain good treatments for different cancer types, both the spot scanning method and the double-scattering method are adopted in the facility, whereas the nozzles include both gantry and fixed beam types. The proton accelerator chain includes a synchrotron of 250 MeV in maximum energy, an injector of 7 MeV consisting of an RFQ and a DTL linac, with a repetition rate of 0.5 Hz. The slow extraction using the third-order resonance and together with the RFKO method is considered to be a good method to obtain a stable and more-or-less homogenous beam spill. To benefit the spot scanning 200 between 60 MeV and 230 MeV. A new method method, the extraction energy can be as many as about - the emittance balancing technique of using a solenoid or a quadrupole rotator is proposed to solve the problem of unequal emittance in the two transverse planes with a beam slowly extracted from a synchrotron. The facility has been designed to keep the potential to be upgraded to include the carbon therapy in the future.     

Y2BaCuO5粒子对顶部籽晶熔融织构YBCO微结构的影响

本文主要研究了Y211相粒子在顶部籽晶熔融织构YBCO块材中的分布及其对材料超导特性的影响.研究发现,在籽晶正下方,YBCO超导块材中的Y211粒子分布呈不均匀性.样品在近籽晶处Y211粒子非常少,从样品顶部到样品底部Y211相粒子的容积率呈增大趋势.由于Y123粒子和Y211粒子热膨胀系数存在差异,这种不均匀性导致了块材内部产生微裂纹,从而降低了磁悬浮力.     

四角状ZF-7玻璃双层光路电流传感头研究

利用线偏振光在ZF-7玻璃中多次全反射构成块状四角双层光路电流传感头.本文分析了入射面相互垂直的相邻二次全反射的P与S分量之间的位相及其相互抵消.对该传感头进行了实验测试.     

Effects of injection beam parameters and foil scattering for CSNS/RCS

The China Spallation Neutron Source (CSNS) uses H- stripping and phase space painting method to fill a large ring acceptance with a small emittance linac beam. The dependence of the painting beam on the injection beam parameters was studied for the Rapid Cycling Synchrotron (RCS). The simulation study was done for injection with different momentum spreads, different rms emittances of the injection beam, and different matching conditions. Then, the beam loss, 99% and rms emittances were obtained, and the optimized injection beam parameters were given. The interaction between H- beam and stripping foil was studied, and the effect of foil scattering was simulated. The stripping efficiency was calculated and the suitable thickness of stripping foil was obtained. In addition, the energy deposition on the foil and the beam loss due to the foil scattering were also studied.     

5种多糖类手性柱分离19种手性多氯联苯的对比研究

采用高效液相色谱在正相条件下对常温稳定存在的19种手性多氯联苯(Polychlorinated biphenyls,PCBs)进行了拆分,对比了5种不同多糖类手性色谱柱的拆分效果.其中Lux Cellulose-1,Cellulose-3和Cellulose-4分离效果较好,在Cellulose-1上PCBs91,136,139,149和171可基线分离,在Cellulose-3上PCBs45,84,88,95,131,135,144和149能够完全分离,在Cellulose-4上PCBs88,131,139,171和174能够完全分离,在以上3种色谱柱上PCBs132,175,176,183,196和197可部分分离,但Cellulose-2和Amylose-2对这19种手性PCBs分离效果很差.考察了温度对拆分的影响,结果在5℃～30℃C之间,PCBs对映体在Cellulose-1和Cellulose-3上对应的范特霍夫方程线性关系较好,而Cellulose-4受柱温影响不稳定.手性PCBs拆分过程整体受焓驱动,温度降低有利于对映体分离.利用在线旋光确定了各PCBs的对映体洗脱顺序,结果表明PCBs对映体的拆分程度和旋光洗脱顺序受苯环上氯原子取代数目和取代位置的影响.     

苯并咪唑衍生物的微波辅助合成研究

开展了邻苯二胺与4-甲基苯甲醛、4-硝基苯甲醛及4-二甲氨基苯甲醛反应生成苯并咪唑衍生物的微波辅助合成研究。用高效液相色谱法(HPLC)测定其产率。结果表明:相同反应时间,在微波辅助条件下,生成苯并咪唑衍生物的反应产率均较常规加热条件下增大,并且芳醛对位上取代基吸电子能力越强,反应产率越高。