排序方式: 共有20条查询结果,搜索用时 15 毫秒
1.
2.
3.
4.
Beam dynamics and rf designs of a 104 MHz ladder type IH-RFQ (L-IH-RFQ) accelerator are finished at Peking University for the acceleration of 14C+ from 40 keV to 500 keV. As a specific feature, the output beam energy spread is as low as 0.6% achieved with the internal discrete bunching method, which makes potential applications of RFQ feasible, such as accelerator mass spectrometry and ion implantation. Tolerances of the beam dynamics design are studied by means of changing the input beam parameters, and the results are quite satisfying. On the other hand, the L-IH-RFQ structure is employed, taking advantage of its mechanical stability and the absence of inter-electrode voltage asymmetry. Radio-frequency properties are studied and optimized for reducing power loss with Microwave Studio (MWS). Tuning of the field flatness and frequency is investigated in principle. 相似文献
5.
介绍了SFRFQ加速系统的最新研究进展. 为验证SFRFQ结构的抗打火性能, 设计了一个高功率模型腔, 进行了高功率打火实验, 并最终证明了该结构的可行性. 为验证SFRFQ加速器的载束性能, 设计了一台长度仅为1m的600keV O+ SFRFQ加速器, 它将把从1MeV ISR RFQ引出的O+离子加速到1.6MeV. 为解决1MeV ISR RFQ引出束流与SFRFQ加速器的横向匹配问题, 在其间插入了一个三单元磁四极透镜. SFRFQ加速器加工和1MeV ISR RFQ改造的进展顺利. 相似文献
6.
A four-rod radio frequency quadruple (RFQ) cavity has been built for the Peking University Neutron Imaging Facility (PKUNIFTY). The rf tuning of such a cavity is important to make the field distribution flat and to tune the cavity's resonant frequency to its operating value. Plate tuners are used to tune the RFQ, which have an effect on both the cavity frequency and field distribution. The rf performance of the RFQ and the effect of plate tuners are simulated. Based on the simulation, a code RFQTUNING is designed, which gives a fast way to tune the cavity. With the aid of the code the cavity frequency is tuned to 201.5 MHz and the flatness deviation of the field distribution is reduced to less than 5%. 相似文献
7.
8.
9.
介绍了北京大学分离作用射频四极场(RFQ)加速器的结构特点,包括膜片式电极、支撑环式电极支撑系统、水冷系统、调谐系统及其工艺实现;介绍了基于该分离作用RFQ加速腔进行的调谐测试、高功率实验和束流实验。结果表明:调谐系统的频率调节范围及品质因数完全满足实验要求;分离作用RFQ加速腔的输入功率可以达到33 kW以上,满足高功率下稳定运行的条件;在束流实验中,把1.03 MeV的O+入射束流加速到1.65 MeV,半高宽能散小于3%。加速器结构满足物理设计要求,加速系统运行稳定。 相似文献
10.
噻唑橙(Thiazole orange,TO)在游离状态下几乎没有荧光,但当其与富G的DNA结合后,会产生很强的荧光增强效应。据此,利用TO识别有无钾离子存在时富G序列的构象变化,建立了一种基于核酸适体(Aptamer)构象效应进行钾离子检测的无标记荧光检测方法。在优化实验条件下,钾离子浓度在(1~60)×10-6mol/L和(4~9)×10-4mol/L范围内与荧光强度呈良好的线性关系,检出限(S/N=3)为2.2×10-7mol/L。对Li+、Na+、Ca2+、Mg2+、NH4+5种离子进行对照试验的结果表明,该方法不仅具有较好的灵敏度还具有较好的选择性,且无需对DNA进行标记,成本低,分析速度快。 相似文献