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Performance of the resonant Schottky pickup at CSRe
No full text<span style="color: rgb(51, 51, 51); font-family: arial, helvetica, sans-serif; font-size: 13px; line-height: 22px; background-color: rgb(248, 248, 248);">For a bunched beam, </span><span class="hitHilite" style="margin: 0px; list-style: none; padding: 0px; color: rgb(51, 51, 51); font-family: arial, helvetica, sans-serif; font-size: 13px; line-height: 22px; background-color: rgb(255, 255, 0);">the</span><span style="color: rgb(51, 51, 51); font-family: arial, helvetica, sans-serif; font-size: 13px; line-height: 22px; background-color: rgb(248, 248, 248);"> signals on pickups are coherent, providing a signal power proportional to </span><span class="hitHilite" style="margin: 0px; list-style: none; padding: 0px; color: rgb(51, 51, 51); font-family: arial, helvetica, sans-serif; font-size: 13px; line-height: 22px; background-color: rgb(255, 255, 0);">the</span><span style="color: rgb(51, 51, 51); font-family: arial, helvetica, sans-serif; font-size: 13px; line-height: 22px; background-color: rgb(248, 248, 248);"> square </span><span class="hitHilite" style="margin: 0px; list-style: none; padding: 0px; color: rgb(51, 51, 51); font-family: arial, helvetica, sans-serif; font-size: 13px; line-height: 22px; background-color: rgb(255, 255, 0);">of</span><span style="color: rgb(51, 51, 51); font-family: arial, helvetica, sans-serif; font-size: 13px; line-height: 22px; background-color: rgb(248, 248, 248);"> </span><span class="hitHilite" style="margin: 0px; list-style: none; padding: 0px; color: rgb(51, 51, 51); font-family: arial, helvetica, sans-serif; font-size: 13px; line-height: 22px; background-color: rgb(255, 255, 0);">the</span><span style="color: rgb(51, 51, 51); font-family: arial, helvetica, sans-serif; font-size: 13px; line-height: 22px; background-color: rgb(248, 248, 248);"> number </span><span class="hitHilite" style="margin: 0px; list-style: none; padding: 0px; color: rgb(51, 51, 51); font-family: arial, helvetica, sans-serif; font-size: 13px; line-height: 22px; background-color: rgb(255, 255, 0);">of</span><span style="color: rgb(51, 51, 51); font-family: arial, helvetica, sans-serif; font-size: 13px; line-height: 22px; background-color: rgb(248, 248, 248);"> particles. For a coasting beam</span><span class="hitHilite" style="margin: 0px; list-style: none; padding: 0px; color: rgb(51, 51, 51); font-family: arial, helvetica, sans-serif; font-size: 13px; line-height: 22px; background-color: rgb(255, 255, 0);">the</span><span style="color: rgb(51, 51, 51); font-family: arial, helvetica, sans-serif; font-size: 13px; line-height: 22px; background-color: rgb(248, 248, 248);"> individual particle signals have a random phase; therefore, </span><span class="hitHilite" style="margin: 0px; list-style: none; padding: 0px; color: rgb(51, 51, 51); font-family: arial, helvetica, sans-serif; font-size: 13px; line-height: 22px; background-color: rgb(255, 255, 0);">the</span><span style="color: rgb(51, 51, 51); font-family: arial, helvetica, sans-serif; font-size: 13px; line-height: 22px; background-color: rgb(248, 248, 248);"> overall signal is proportional to </span><span class="hitHilite" style="margin: 0px; list-style: none; padding: 0px; color: rgb(51, 51, 51); font-family: arial, helvetica, sans-serif; font-size: 13px; line-height: 22px; background-color: rgb(255, 255, 0);">the</span><span style="color: rgb(51, 51, 51); font-family: arial, helvetica, sans-serif; font-size: 13px; line-height: 22px; background-color: rgb(248, 248, 248);"> particle number N. As a consequence, </span><span class="hitHilite" style="margin: 0px; list-style: none; padding: 0px; color: rgb(51, 51, 51); font-family: arial, helvetica, sans-serif; font-size: 13px; line-height: 22px; background-color: rgb(255, 255, 0);">Schottky</span><span style="color: rgb(51, 51, 51); font-family: arial, helvetica, sans-serif; font-size: 13px; line-height: 22px; background-color: rgb(248, 248, 248);"> signals are often relatively weak and have to compete with many noise sources. For a small number </span><span class="hitHilite" style="margin: 0px; list-style: none; padding: 0px; color: rgb(51, 51, 51); font-family: arial, helvetica, sans-serif; font-size: 13px; line-height: 22px; background-color: rgb(255, 255, 0);">of</span><span style="color: rgb(51, 51, 51); font-family: arial, helvetica, sans-serif; font-size: 13px; line-height: 22px; background-color: rgb(248, 248, 248);"> particles, </span><span class="hitHilite" style="margin: 0px; list-style: none; padding: 0px; color: rgb(51, 51, 51); font-family: arial, helvetica, sans-serif; font-size: 13px; line-height: 22px; background-color: rgb(255, 255, 0);">the</span><span style="color: rgb(51, 51, 51); font-family: arial, helvetica, sans-serif; font-size: 13px; line-height: 22px; background-color: rgb(248, 248, 248);"> SIN is always a problem. To achieve a high signal-to-noise ratio and better temporal resolution, which could yield important physical information about fast processes, a </span><span class="hitHilite" style="margin: 0px; list-style: none; padding: 0px; color: rgb(51, 51, 51); font-family: arial, helvetica, sans-serif; font-size: 13px; line-height: 22px; background-color: rgb(255, 255, 0);">resonant</span><span style="color: rgb(51, 51, 51); font-family: arial, helvetica, sans-serif; font-size: 13px; line-height: 22px; background-color: rgb(248, 248, 248);"> </span><span class="hitHilite" style="margin: 0px; list-style: none; padding: 0px; color: rgb(51, 51, 51); font-family: arial, helvetica, sans-serif; font-size: 13px; line-height: 22px; background-color: rgb(255, 255, 0);">pickup</span><span style="color: rgb(51, 51, 51); font-family: arial, helvetica, sans-serif; font-size: 13px; line-height: 22px; background-color: rgb(248, 248, 248);"> was developed </span><span class="hitHilite" style="margin: 0px; list-style: none; padding: 0px; color: rgb(51, 51, 51); font-family: arial, helvetica, sans-serif; font-size: 13px; line-height: 22px; background-color: rgb(255, 255, 0);">at</span><span style="color: rgb(51, 51, 51); font-family: arial, helvetica, sans-serif; font-size: 13px; line-height: 22px; background-color: rgb(248, 248, 248);"> GSI (Nolden et al., 2011 [1]), and a similar device is now installed in </span><span class="hitHilite" style="margin: 0px; list-style: none; padding: 0px; color: rgb(51, 51, 51); font-family: arial, helvetica, sans-serif; font-size: 13px; line-height: 22px; background-color: rgb(255, 255, 0);">the</span><span style="color: rgb(51, 51, 51); font-family: arial, helvetica, sans-serif; font-size: 13px; line-height: 22px; background-color: rgb(248, 248, 248);"> </span><span class="hitHilite" style="margin: 0px; list-style: none; padding: 0px; color: rgb(51, 51, 51); font-family: arial, helvetica, sans-serif; font-size: 13px; line-height: 22px; background-color: rgb(255, 255, 0);">CSRe</span><span style="color: rgb(51, 51, 51); font-family: arial, helvetica, sans-serif; font-size: 13px; line-height: 22px; background-color: rgb(248, 248, 248);"> [2] </span><span class="hitHilite" style="margin: 0px; list-style: none; padding: 0px; color: rgb(51, 51, 51); font-family: arial, helvetica, sans-serif; font-size: 13px; line-height: 22px; background-color: rgb(255, 255, 0);">at</span><span style="color: rgb(51, 51, 51); font-family: arial, helvetica, sans-serif; font-size: 13px; line-height: 22px; background-color: rgb(248, 248, 248);"> IMP. This device will be used for nuclear mass and lifetime measurement, as well as other uses. </span><span class="hitHilite" style="margin: 0px; list-style: none; padding: 0px; color: rgb(51, 51, 51); font-family: arial, helvetica, sans-serif; font-size: 13px; line-height: 22px; background-color: rgb(255, 255, 0);">The</span><span style="color: rgb(51, 51, 51); font-family: arial, helvetica, sans-serif; font-size: 13px; line-height: 22px; background-color: rgb(248, 248, 248);"> final goal </span><span class="hitHilite" style="margin: 0px; list-style: none; padding: 0px; color: rgb(51, 51, 51); font-family: arial, helvetica, sans-serif; font-size: 13px; line-height: 22px; background-color: rgb(255, 255, 0);">of</span><span style="color: rgb(51, 51, 51); font-family: arial, helvetica, sans-serif; font-size: 13px; line-height: 22px; background-color: rgb(248, 248, 248);"> </span><span class="hitHilite" style="margin: 0px; list-style: none; padding: 0px; color: rgb(51, 51, 51); font-family: arial, helvetica, sans-serif; font-size: 13px; line-height: 22px; background-color: rgb(255, 255, 0);">the</span><span style="color: rgb(51, 51, 51); font-family: arial, helvetica, sans-serif; font-size: 13px; line-height: 22px; background-color: rgb(248, 248, 248);"> </span><span class="hitHilite" style="margin: 0px; list-style: none; padding: 0px; color: rgb(51, 51, 51); font-family: arial, helvetica, sans-serif; font-size: 13px; line-height: 22px; background-color: rgb(255, 255, 0);">pickup</span><span style="color: rgb(51, 51, 51); font-family: arial, helvetica, sans-serif; font-size: 13px; line-height: 22px; background-color: rgb(248, 248, 248);"> is to detect single particles. In Dec 2012, we performed an experiment with a Sn-112(50+) beam with an energy</span><span class="hitHilite" style="margin: 0px; list-style: none; padding: 0px; color: rgb(51, 51, 51); font-family: arial, helvetica, sans-serif; font-size: 13px; line-height: 22px; background-color: rgb(255, 255, 0);">of</span><span style="color: rgb(51, 51, 51); font-family: arial, helvetica, sans-serif; font-size: 13px; line-height: 22px; background-color: rgb(248, 248, 248);"> 253 MeV/u, and </span><span class="hitHilite" style="margin: 0px; list-style: none; padding: 0px; color: rgb(51, 51, 51); font-family: arial, helvetica, sans-serif; font-size: 13px; line-height: 22px; background-color: rgb(255, 255, 0);">the</span><span style="color: rgb(51, 51, 51); font-family: arial, helvetica, sans-serif; font-size: 13px; line-height: 22px; background-color: rgb(248, 248, 248);"> single particle sensitivity </span><span class="hitHilite" style="margin: 0px; list-style: none; padding: 0px; color: rgb(51, 51, 51); font-family: arial, helvetica, sans-serif; font-size: 13px; line-height: 22px; background-color: rgb(255, 255, 0);">of</span><span style="color: rgb(51, 51, 51); font-family: arial, helvetica, sans-serif; font-size: 13px; line-height: 22px; background-color: rgb(248, 248, 248);"> </span><span class="hitHilite" style="margin: 0px; list-style: none; padding: 0px; color: rgb(51, 51, 51); font-family: arial, helvetica, sans-serif; font-size: 13px; line-height: 22px; background-color: rgb(255, 255, 0);">the</span><span style="color: rgb(51, 51, 51); font-family: arial, helvetica, sans-serif; font-size: 13px; line-height: 22px; background-color: rgb(248, 248, 248);"> </span><span class="hitHilite" style="margin: 0px; list-style: none; padding: 0px; color: rgb(51, 51, 51); font-family: arial, helvetica, sans-serif; font-size: 13px; line-height: 22px; background-color: rgb(255, 255, 0);">pickup</span><span style="color: rgb(51, 51, 51); font-family: arial, helvetica, sans-serif; font-size: 13px; line-height: 22px; background-color: rgb(248, 248, 248);"> was successfully confirmed. This paper presents hardware measurements </span><span class="hitHilite" style="margin: 0px; list-style: none; padding: 0px; color: rgb(51, 51, 51); font-family: arial, helvetica, sans-serif; font-size: 13px; line-height: 22px; background-color: rgb(255, 255, 0);">of</span><span style="color: rgb(51, 51, 51); font-family: arial, helvetica, sans-serif; font-size: 13px; line-height: 22px; background-color: rgb(248, 248, 248);"> </span><span class="hitHilite" style="margin: 0px; list-style: none; padding: 0px; color: rgb(51, 51, 51); font-family: arial, helvetica, sans-serif; font-size: 13px; line-height: 22px; background-color: rgb(255, 255, 0);">the</span><span style="color: rgb(51, 51, 51); font-family: arial, helvetica, sans-serif; font-size: 13px; line-height: 22px; background-color: rgb(248, 248, 248);"> </span><span class="hitHilite" style="margin: 0px; list-style: none; padding: 0px; color: rgb(51, 51, 51); font-family: arial, helvetica, sans-serif; font-size: 13px; line-height: 22px; background-color: rgb(255, 255, 0);">pickup</span><span style="color: rgb(51, 51, 51); font-family: arial, helvetica, sans-serif; font-size: 13px; line-height: 22px; background-color: rgb(248, 248, 248);"> as well as beam measurements. (C) 2013 Elsevier B.V. All rights reserved.</span
Feedback of slow extraction in CSRm
No full text<span style="color: rgb(51, 51, 51); font-family: arial, helvetica, sans-serif; font-size: 13px; line-height: 22px; background-color: rgb(248, 248, 248);">The transverse tune of the beam in a synchrotron will fluctuate due to the main quadrupole power supply ripple, which leads the spill ripple through the variation of the separatrices area. To reduce the spill ripple, an additional pair of fast-response quadrupoles (FQ) is adopted to compensate for the tune ripple caused by the main quadrupoles. After using the FQ feedback, the amplitude of the spill ripple with a frequency of less than 800 Hz has been reduced to a tenth of that in the normal mode. (c) 2013 Elsevier B.V. All rights reserved.</span
2. 45 GHz强流脉冲质子源
No full text<span style="color: rgb(51, 51, 51); font-family: arial, helvetica, sans-serif; font-size: 13px; line-height: 22px; background-color: rgb(248, 248, 248);">介绍了一台用于强流质子直线加速器注入的2. 45 GHz电子回旋共振强流脉冲质子源。采用2. 45 GHz的微波馈入实现以氢气为载气的氢等离子体,在三电极引出系统下获得能量50 keV,50 mA的强流脉冲离子束。其中三电极分别为等离子体电极、抑制电极及地电极。用CST仿真软件和PBGUNS分别模拟计算了匹配波导能量的传输效率与引出束流传输轨迹,得出信号输入端口反射系数S_(11)约为0.119,整个匹配波导内正向传输系数S_(11)为0.993,引出束流在Z=26 cm处,束流包络约为2 cm。研究了离子源轴向磁场变化对引出束流强度的影响,结果得出,当螺线管电流从0 A增加至50 A时,引出混合束流强度从20 mA上升至50 mA</span><span style="color: rgb(51, 51, 51); font-family: arial, helvetica, sans-serif; font-size: 13px; line-height: 22px; background-color: rgb(248, 248, 248);">A 2. 45 GHz high current pulsed proton source for proton linear accelerator injector was introduced. Hydrogen plasma was obtained using a microwave feeding at the frequency of 2.45 GHz. A 50 keV, 50 mA pulsed beam was extracted by a 3-electrode system consisting of the plasma electrode, suppression electrode and grounded electrode. The characteristics of extracted beam and impedance matching of the transitional waveguide were studied by by CST and PBGUNS codes. The effect of the axial magnetic field distribution on extraction beam was studied by 2D-Poission code. The transmission and reflection coefficients were 0. 993 and 0. 119, respectively, when the frequency varied from 1.8 to 3.2 GHz. The results show that the total ion current reaches from 0 to 50 A, and the current of the extraction beam reaches from 20 to 50 mA.</span
伊维菌素缓释微球的制备方法
No full text<span style="color: rgb(69, 69, 69); font-family: Arial, Helvetica, sans-serif; line-height: 21px; text-indent: 24px;"> 本发明涉及一种动物医药、动物保健注射用伊维菌素缓释微球及其制备方法，属于生物医用高分子材料与药物控释制剂的交叉研究领域。一种伊维菌素缓释微球，其主要特点在于所述的伊维菌素缓释微球粒径为0.1～10μm，载药量为20%～35%，包封率在80%以上；伊维菌素缓释微球的制备方法包括如下步骤：将所述载体材料与药物伊维菌素以质量百分比为1：1～10溶于有机溶剂中经超声波或机械搅拌充分乳化制成油相，所述的油相与水相的体积比为1：5～10；在温度为-10℃～30℃，将所述油相分步骤注射到水相分散介质溶液中，恒温磁力搅拌，转速400～10000rpm充分乳化，得到S/O/W型乳液；然后在室温下搅拌乳液3～4h至有机溶剂挥发完全，再经离心、洗涤、收集、室温真空0.01～0.04MPa干燥，时间为10-12h或冷冻干燥，温度为-0℃～-20℃，得到粒径为0.1～10μm的伊维菌素缓释微球。</span
离子治癌加速器数字电源调节系统及调节方法
No full text<span style="color: rgb(69, 69, 69); font-family: Arial, Helvetica, sans-serif; line-height: 21px; text-indent: 24px;"> 本发明涉及一种基于NiosII双核的离子治癌加速器数字电源调节系统，可以适用于离子治癌加速器多种拓扑类型的高精度数字电源脉冲和直流运行方式。一种离子治癌加速器数字电源调节系统，包括FPGA芯片，Flash模块、内存单元同步动态随机存储器、同步静态随机存取存储器、系统的调试接JTAG接口、以太网芯片、光纤接收器、通用异步接收/发送装置串行通信设备和串行存贮器、ADC模数转换器、DAC数模转换器、用电源故障保护信号输入通道模块和脉宽调制信号输出通道模块均与FPGA芯片的管脚相连，还包括FPGA芯片上系统。本发明还提供根据此装置实现离子治癌加速器数字电源调节的方法。</span
X ray spectra induced by ~(129)Xe~(30+) impacting the Au surface
No full text<span style="color: rgb(51, 51, 51); font-family: arial, helvetica, sans-serif; font-size: 13px; line-height: 22px; background-color: rgb(248, 248, 248);">当不同动能(350-600keV)高电荷态离子~(129)Xe~(30+)入射Au表面过程中,发出了1.65keV的X射线和靶原子的Malpha特征X射线.分析表明:高电荷态离子与Au表面相互作用过程中,Xe离子3d壳层的电子被激发,形成空穴,4f电子偶极跃迁辐射1.65keVM-X射线.同时,靶原子Au的3s电子被激发,退激辐射M-X射线.利用经典过垒模型解释了Xe的M-X射的产额随入射离子的动能增加而减小,靶原子的特征X射线产额随入射离子的动能增加而增加的原因.</span><span style="color: rgb(51, 51, 51); font-family: arial, helvetica, sans-serif; font-size: 13px; line-height: 22px; background-color: rgb(248, 248, 248);">X ray emission from Xe30+ions(kinetic energy 350-600 keV)impacting on an Au target surface was investigated.The 1.65 keV M-X ray and the Au atomic Malpha characteristic X rays were measured.The results show that because the 3d electron of the Xe ion is excited to occur a vacancy,the 1.65 keV M-X ray are emit from the electron transition between 4f to 3d energy level.The 3s electron of the Au target atom is ionized to form a hole in the M-shell,the Malpha characteristic X rays are radiated by 4f electron filling in the hole.It was also found that the yield of such characteristic X rays is decreasing with increasing the projectile kinetic energy.The yield of the characteristic Au X rays increases with increasing the projectile kinetic energy.These phenomena are analyzed with the classical coulomb over the barrier mode.</span
Stress and Strain Measurements on a 5 T Superconducting Magnet During Coil Excitation
No full text<span style="color: rgb(51, 51, 51); font-family: arial, helvetica, sans-serif; font-size: 13px; line-height: 22px; background-color: rgb(248, 248, 248);">A 5 T superconducting magnet with a warm bore has been successfully fabricated and tested at the Institute of Modern Physics of Chinese Academy of Science (IMPCAS). The strains of the superconducting magnet under cryogenic temperature and intense magnetic field were measured by using low-temperature resistance strain gauges where the compensation methods were introduced for eliminating noise effects of both temperature and magnetic field on the strain measurement. A slow ramp rate of the magnetic field was applied during coil excitation of the superconducting magnet to avoid the temperature risen by eddy current. A wireless strain acquisition system was used for the hoop and axial strain measurements of the magnet. It is clarified that the strains measured in the superconducting magnet give much valuable information characterizing the deformation and the stress state at cryogenic temperature and intense magnetic fields. For the purpose of comparison, the steady-state strains and central magnetic field of the superconducting magnet was valuated by means of a coupled FEM. The simulation predictions and the experimental data show good agreements.</span
Electromagnetic simulation study of dielectric wall accelerator structures
No full text<span style="color: rgb(51, 51, 51); font-family: arial, helvetica, sans-serif; font-size: 13px; line-height: 22px; background-color: rgb(248, 248, 248);">Two types of dielectric wall accelerator (DWA) structures, a bi-polar Blumlein line and zero integral pulse line (ZIP) structures were investigated. The high gradient insulator simulated by the particle in cell code confirms that it has little influence on the axial electric field. The results of simulations using CST microwave studio indicate how the axial electric field is formed, and the electric field waveforms agree with the theoretical one very well. The influence of layer-to-layer coupling in a ZIP structure is much smaller and the electric field waveform is much better. The axial of the Blumlein structure's electric field has better axial stability. From both of the above, it found that for a shorter pulse width, the axial electric field is much higher and the pulse stability and fidelity are much better. The CST simulation is very helpful for designing DWA structures.</span
变频调谐腔
No full text本实用新型主要涉及在真空情况下形成高频高压电场，并在束流运动方向对重粒子束进行俘获、加速的铁氧体加载的宽频带高频高压同步加速器装置技术领域，尤其涉及一种大功率铁氧体加载变频调谐腔。一种变频调谐腔，包括一个同轴谐振腔，所述的同轴谐振腔包括有由同轴连接的谐振腔A和谐振腔B组成，谐振腔A和谐振腔B结构相同，通过法兰连接，其主要特点在于：在所述同轴谐振腔的粒子束流管道引入端一侧通过波纹管连接有加速缝，加速缝的另一端与粒子束流引入端相连；绝缘陶瓷设于加速缝上；在加速缝之间设置有腔体调谐用高压真空电容器和高频功率源的末级功放电子管，电子管阳极输出射频高压加载在加速缝间隙两端
Positron annihilation study of proton-irradiated reactor pressure vessel steels
No full textThe microstructures, irradiation-induced defects and changes of mechanical property of Chinese domestic A508-3 steels after proton irradiation were investigated by TEM, positron lifetime, slow positron beam Doppler broadening spectroscopy and hardness measurements. The defects were induced by 240 keV proton irradiation with fluences of 1.25 x 10(17) ions cm(-2) (0.26 dpa). 2.5 x 10(17) ions cm(-2) (0.5 dpa), and 5.0 X 10(17) ions cm(-2) (1.0 dpa). The TEM observation revealed that the as-received steel had typical bainitic-ferritic microstructures. It was also observed that Doppler broadening S-parameter and average lifetime increased with dose level owing to the formation of defects and voids induced by proton irradiation. The correlation between positron parameters and hardness was found. (c) 2012 Elsevier Ltd. All rights reserved