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真空管道式束流调节器
No full text<font face="宋体" size="3">本实用新型主要涉及电真空领域，尤其涉及一种束流调节装置。一种真空管道式束流调节器，包括正高压电极，负高压电极，高压馈线，所述的正高压电极，负高压电极通过密封固定装置平行设置在真空管道内；在真空管道上设有圆盘绝缘装置，所述的正高压电极和负高压电极通过高压馈线与圆盘绝缘装置相连接；所述的圆盘绝缘装置还与正、负高压输出线相连接。本实用新型提供的装置形成的电场水平可以达到10KV以上，真空度高于2×10-5Pa。具有输送电压大、高真空、结构紧凑、使用可靠。</font
电荷频率转化器
No full text<p><font face="宋体" size="3">发明是测量电荷(电流)信号并将其转换成频率输出的前端测量电路。一种电荷频率转换器，其主要特点在于：电流信号输入端P1通过电阻R2与积分电路(1)的输入端连接；积分电路(1)的输出端通过幅度鉴别电路(2) 与窄脉冲成形电路(3)的输入端相连接；窄脉冲成形电路(3)的输出1端分别与延时电路(4)的输入端、输出脉冲整形电路(6)的输入端和第一泄放开关(8)的控制端相连接；延时电路(4)的输出端通过幅度控制与耦合电路(5)与泄放支路相连接；窄脉冲成形电路(3)的输出2端与第二泄放开关(9)的控制端相连接；输出脉冲整形电路(6)的输出端与频率输出级电路(7)相连接。本发明为束流强度检测探测器的信号读出提供了一种结构简单、性能可靠的测量电路。</font></p
Numerical optimization and multi-particle dynamics simulation of the radial matching section of the RFQ
No full textThe ABC code is an optimization program for the development of matching channels and dynamical matchers in radio frequency quadrupole (RFQ) structures, and a new approach to this code to define the geometry of the radial matching section of the RFQ has been developed. This approach is based on the application of the numerical optimization step by step. This optimization is intended to search for the initial matching condition of a beam, the optimization of parameters of a cell of the channel on given characteristic parameters and traces of a beam in linear channels in both forward and backward directions. To further verify the results of the optimization, multi-particle beam dynamics simulations have been carried out using the BEAMPATH and TRACK codes. The result of the beam dynamics simulation shows that the optimization result of the ABC code is reasonable and this approach provides an opportunity to redesign the structure of the radial matching section of the RFQ
大功率脉冲开关电源A型母排叠层方法
No full text本发明公开大功率脉冲开关电源A型母排叠层方法，其结构特征是：选用4 个整流桥模块并联整流和2个IGBT模块输出主电路，主电路中滤波电容，功率开关管或整流器，电感或变压器放置靠近，并确定好这些器件的方向即在大功率开关电源设计中，电容板，A、B、C、正极相输入铜板均采用铜板叠层而安装，减少了走线，克服导线电感和阻抗的影响，进而减小了电磁干扰，达到了抑制电磁干扰的目的
高频变谐波同步加速的方法及其控制装置
No full text<p><font face="宋体" size="3">发明涉及质子-重离子治癌同步加速器中加速离子的方法技术领域，具体涉及一种高频变谐波同步加速的方法及其控制装置。其采用与高频变谐波同步加速相对应的控制装置，并利用同步加速器中的高频腔首先采用频率等于储存离子回旋频率的高次谐波(2次或4次)的高频电场加速离子，当加速至一定的中间能量时，将高频腔的高频电场频率改变为储存离子回旋频率的低次谐波(1次或2次)，继续加速离子直至临床所需要的能量。在高频腔工作频率范围内，采用高频变谐波加速技术，避免了铁氧体加载高频系统宽频带加速时低端扩展的困难。其在较窄的高频腔工作频率范围的基础上，拓宽俘获和加速离子的能量范围，实现人体不同深度肿瘤的离子束照射治疗对束流能量的要求。</font></p
Mechanical Properties and Defect Evolution of Kr-Implanted 6H-SiC
No full textSpecimens of silicon carbide (6H-SiC) were irradiated with 5 MeV Kr ions ((84)Kr(19+)) for three fluences of 5x10(13), 2x10(14) and 1x10(15) ions/cm(2), and subsequently annealed at room temperature, 500 degrees C, 700 degrees C and 1000 degrees C, respectively. The strain of the specimens was investigated with high resolution XRD and different defect evolution processes are revealed. An interpretation of the defect evolution and migration is given to explain the strain variation. The mechanical properties of the specimens were studied by using a nano-indentation technique in continuous stiffness measurement (CSM) mode with a diamond Berkovich indenter. For specimens irradiated with fluences of 5x10(13) or 2x10(14) ions/cm(2), hardness values exceed that of un-implanted SiC. However, hardness sharply degrades for specimens irradiated with the highest fluence of 1x10(15) ions/cm(2). The specimens with fluences of 5x10(13) and 2x10(14) ions/cm(2) and subsequently annealed at 700 degrees C and 500 degrees C, respectively, show the maximum hardness value
Structural and optical study of irradiation effect in GaN epilayers induced by 308 MeV Xe ions
No full textWurtzite GaN epilayers irradiated at room temperature with 308 MeV (129)Xe(35+) ions to fluences of 1 x 10(13) and 3 x 10(13) cm(-2) have been studied by contact mode atomic force microscopy (AFM), high-resolution X-ray diffraction (HRXRD), micro-Raman scattering and photoluminescence (PL) spectroscopy. The AFM images showed that the surface of GaN films was etched efficiently due to the Xe ion irradiation. The initial step-terrace structure on GaN surface was eliminated completely at a fluence of 3 x 10(13) cm(-2). HRXRD and Raman results indicated that the Xe ion irradiation led to a homogenous lattice expansion throughout the entire similar to 3 mu m-thick GaN films. The lattice expansion as well as the biaxial compressive stress of the films was increasing with the increase of ion fluence. PL measurements showed that a dominant yellow luminescence band in the as-grown GaN films disappeared, but a blue and a green luminescence bands were produced after irradiation. Based on these results, the strong electronic excitation effect of 308 MeV Xe ions in GaN is discussed. (C) 2011 Elsevier B.V. All rights reserved
HRXRD and Raman study of irradiation effects in InGaN/GaN layers induced by 2.3 MeV Ne and 5.3 MeV Kr ions
No full textIn(0.15)Ga(0.83)N/GaN bilayers irradiated with 2.3 MeV Ne and 5.3 MeV Kr ions at room temperature were studied by high-resolution X-ray diffraction (HRXRD) and micro-Raman scattering. The Ne ion fluences were in the range from 1 x 10(12) to 1 x 10(15) cm(-2), and the Kr ion fluences were in the range from 1 x 10(11) to 1 x 10(13) cm(-2). Results show that the structures of both In(0.15)Ga(0.85)N and GaN layers remained almost unchanged for increasing fluences up to 1 x 10(13) and 1 x 10(12) cm(-2) for Ne and Kr ion irradiations, respectively. After irradiation to higher fluences, the GaN layer was divided into several damaged layers with different extents of lattice expansion, while the In(0.15)Ga(0.83)N layer exhibited homogenous lattice expansion. The layered structure of GaN and the different responses to irradiation of the GaN and In(0.15)Ga(0.85)N layers are discussed. (C) 2011 Elsevier B.V. All rights reserved
Microstructural evolution upon annealing in Ar-implanted Si
No full textThe annealing effects of crystalline silicon (Si) implanted with argon (Ar) ions at a dose of 2 x 10(16) Ar(+)/cm(2) at room temperature and subsequently annealed at 400-1100 degrees C for 30 min were investigated. The samples were analyzed by transmission electron microscopy and Raman spectroscopy. Before and after annealing up to 600 degrees C, an amorphous layer is formed but Ar bubbles are not observed in the damage layer. After annealing at 800 degrees C, argon bubbles are observed together with extended defects. The damage layer evolves into a polycrystalline structure. After annealing at 1100 degrees C; exfoliation occurs on the sample surface, and microtwin lamellas form in the damage layer. Raman scattering revealed that a strong recrystallization occurs from 600 degrees C to 800 degrees C. The results were compared with the case of helium implantation, with particular focus on bubble formation mechanisms. (C) 2011 Elsevier B.V. All rights reserved