Injection system design for a hadron therapy synchrotron

A synchrotron is designed for tumour therapy with C⁶⁺ ions or proton. Its injector is a cyclotron, which delivers C⁵⁺ or H₂⁺ ions to the synchrotron. After comparing the methods of the single-turn injection, the multi-turn injection and the stripping injection, this paper chooses the stripping injection method. In addition, the concept design of the injection system is presented, in which the     

Simulation study of blue InGaN multiple quantum well light-emitting diodes with different hole injection layers

InGaN-based light-emitting diodes with p-GaN and p-AlGaN hole injection layers are numerically studied using the APSYS simulation software.The simulation results indicate that light-emitting diodes with p-AlGaN hole injection layers show superior optical and electrical performance,such as an increase in light output power,a reduction in current leakage and alleviation of efficiency droop.These improvements can be attributed to the p-AlGaN serving as hole injection layers,which can alleviate the band bending induced by the polarization field,thereby improving both the hole injection efficiency and the electron blocking efficiency.     

Study of Energy Consumption in the Injection Molding Process

A computing method for simulating the energy consumption in an injection molding process using the Moldflow MPI analysis software is proposed. Considering such factors as product structure, processing parameters, and mold structure, it was shown by orthogonal testing that the melt temperature, product diameter, product wall thickness, and gate diameter are the four largest factors impacting on the injection energy consumption. Based on the MATLAB curve fitting toolbox, the relationship between the four main factors and the injection energy consumption was established, and a calculation model for the injection energy consumption was proposed.The accuracy of the model was above 95%. Finally, by using an experimental system of injection energy consumption to research the relationship between energy consumption and actual injection power, and by verifying the calculation accuracy of injection energy consumption of the established model, the results show that the established model can be an excellent predictor of the actual electric energy required and the accuracy of it was above 85% compared with measured experimental data.     

Temperature dependence of spin injection efficiency in an epitaxially grown Fe/GaAs hybrid structure

The electrical spin injection from Fe into an n-doped GaAs channel through Schottky-tunnel-barrier is observed from 1.8 K to room temperature. The magnitude of local spin valve signal (ΔR/R₀) decreases as the temperature increases. In each temperature, we calculated the injected polarization (η) considering the spin drift effect induced by the electric field. The interfacial polarizations of 19.3% and 12.6% are acquired for Fe/GaAs junction at T=1.8 and 300 K, respectively. The temperature dependence of spin injection efficiency is matched with interface resistance variation. As the temperature increases, Schottky-tunnel-barrier property is diminished so that the spin injection efficiency would be reduced.     

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用中平面往复快速扫描6探针组观测HL-2A装置边缘等离子体的扰动特性。在一次放电中能测量到边缘等离子体参数的时空分布及其涨落量，雷诺胁强与极向流和带状流的关系，以及静电涨落驱动的粒子通量和热通量的径向变化。在多发弹丸注入(MPI)和多脉冲超声分子束注入(SMBI)条件下，研究了边缘参数的涨落和相关特性。实验结果表明：SMBI和MPI等注入手段改变了边缘的扰动特性；雷诺胁强的径向梯度可以驱动带状流，抑制湍流输运。     

北京自由电子激光器外注入实验系统设计研究

北京自由电子激光器(BFEL)是一台工作于中红外区Compton型FEL振荡器。本文结合BFEL装置,设计了一套完整的激光外注入光路,利用声光调QCO_2激光器产生的10.6μm激光做激励源注入到BFEL光腔中,以缩短振荡建立时间,提高BFEL输出能量,改善输出激光的相干性。模拟计算结果是:当BFEL光腔中的外注入光强为自发辐射强度的10~5倍时,可使饱和振荡建立时间缩短35％,输出能量提高2倍。     

空间辐射地面模拟装置(SESRI)同步加速器注入设计和模拟研究

国家"十二五"工程将在哈尔滨工业大学建造一台空间辐射地面模拟装置（SESRI）,该装置能够模拟空间辐照环境,对研究离子辐照材料、生命体等具有重要意义。SESRI主要由双ECR离子源,直线注入器,同步环和3个高能实验终端组成。周长为43.9 m的同步环作为装置的核心部分,能够向3个实验终端输送离子种类多、能量范围广的粒子束。为了保证环内有足够的粒子数,注入系统的设计至关重要,SESRI同步环采用多圈注入方案,并利用ACCSIM程序模拟粒子真实运动情况。结果表明,粒子的注入效率为85.5%,离子数增益可达17.1,可满足设计要求。Space Environment Simulation and Research Infrastructure (SESRI), which is one of the large-scale scientific projects proposed in National Twelfth Five-Year Plan of China, will be constructed in Harbin Institution of Technology. The SESRI project dedicated to space radiation consists of two ECR ion sources, a high intensity ion linac, a synchrotron and 3 research terminals. As the key part of the complex, a 43.9 m synchrotron can provide broadest energy range and variable ion beam for each terminal. To obtain required intensity in the synchrotron, the injection system is significant. A multi-turn injection scheme is adopted in the synchrotron and the injection process is simulated by ACCSIM with multi-particle tracking method. The results show that the injection efficiency and intensity gain factor can reach 85.5% and 17.1 respectively. The multi-turn injection system can meet the design requirement.     

HL-2A托卡马克超声分子束注入深度和加料效果研究

超声分子束注入深度与加料效率是分子束加料研究中的基本课题.在近期开展的超声分子束注入实验中，发现分子束注入深度与等离子体电子温度和密度、分子束源的气压和温度有直接关系，获得了分子束注入深度的定标律.在低温气体源(液氮冷却)的分子束注入实验中，发现分子束流中形成了团簇，其注入深度超过30 cm，分析了在低温气源分子束注入实验中的团簇现象. 关键词： 超声分子束注入 注入深度 加料效率 团簇     

Pellet Injection Experiments in the HL-2A Tokamak

The advantages of pellet injection as a competitive means of fuelling a tokamak are well known. They include： （ 1 ） deep deposition of fuel, （ 2 ） better fuelling efficiency, （ 3 ） purer plasma, and so on. Meanwhile, improving plasma performance by pellet injection has been proven in many tokamak experiments. The deposition of pellet particles following pellet injection causes a temporal change of the local plasma temperature and density gradients which affects the transport properties of the plasma, so pellet injection can be used as a method of studying the transport process as well.     

Electroluminescence of excitons in an InGaAs quantum well

We report on electrical injection of excitons in a quantum well placed in the intrinsic region of a p–i–n photodiode. Both the narrow linewidth of the electroluminescence at 70 K and the evolution of the emission spectra with increasing current are signatures of the excitonic character of the emission. This structure is ready to be integrated in semiconductor microcavities in order to evidence the strong coupling regime under electrical injection.     

双阳极磁控注入枪设计参数对其性能的影响分析

 对34GHz基波回旋管双阳极磁控注入枪的优化做了详细的研究和计算，数值模拟了阳极电压、注电流、枪体尺寸加工误差、外加直流磁场等因素对电子枪的影响。模拟结果表明：增大阳极电压不但可以提高速度比，而且可以降低横向速度零散。磁场压缩比减小，使电子注具有最小速度零散的电流值增大；同时，电子注的速度比降低，最小横向速度零散值也增大。必须慎重选择阳极形状，以提高电子枪的性能并保证电子注的稳定性；同时，还发现由于阳极结构的变化导致阴极电场分布的变化，使电子注的注电流在各因子变化过程中出现了微小的扰动。减小Bc可以增大电子注的速度比，还可以减小电子注的横向速度零散，但是当电子注的速度比增大到一定值时，电子注的性能就会变得不太稳定。     

Beam Characteristics of Mechanically Tunable Magnetron Injection Guns

Gyrotron has received extensive attention owing to its high-power capability, particularly when the wavelength shrinks below the millimeter-wave range. The electron beam of a gyrotron is typically generated by a magnetron injection gun (MIG), and a mechanically tunable MIG is employed to enhance the beam quality. However, a slight adjustment in the position of the center electrode of the mechanically tunable MIG can cause significant modification of the electric-field profile. Consequently, the cathode current of the mechanically tunable MIG is not only dependent on the cathode temperature, but also the relative position of center electrode. To accurately determine the beam characteristics of the mechanically tunable MIG, an improved computer program is employed to simulate electron trajectories. Simulation and measurement results indicate that although the magnetic field and compression ratio do not influence the beam current of the mechanically tunable MIG, but the beam current of the MIG depends on the cathode temperature and relative position of the center electrode. Finally, an improved mechanically tunable MIG design is developed to enhanced an beam quality while minimizing beam current variation.     

红花注射剂和野菊花注射剂的红外光谱分析

采用傅里叶变换红外光谱法(FTIR)并结合二阶导数谱和二维相关红外光谱的“三级鉴定”技术,对红花和野菊花注射剂进行质量监测。不仅将它与其主要药材的提取物进行对比,同时也指出了不同批次注射剂之间稳定性的差异。而且通过实验,探索出花类注射剂红外光谱的共性,以及不同注射剂的指纹特征。此法方便易行,分析快速,不污染样品,堪称对中药注射剂进行质量鉴定简单实用的方法。     

双阳极磁控注入枪设计参数对其性能的影响分析

对34GHz基波回旋管双阳极磁控注入枪的优化做了详细的研究和计算,数值模拟了阳极电压、注电流、枪体尺寸加工误差、外加直流磁场等因素对电子枪的影响。模拟结果表明：增大阳极电压不但可以提高速度比,而且可以降低横向速度零散。磁场压缩比减小,使电子注具有最小速度零散的电流值增大;同时,电子注的速度比降低,最小横向速度零散值也增大。必须慎重选择阳极形状,以提高电子枪的性能并保证电子注的稳定性;同时,还发现由于阳极结构的变化导致阴极电场分布的变化,使电子注的注电流在各因子变化过程中出现了微小的扰动。减小Bc可以增大电子注的速度比,还可以减小电子注的横向速度零散,但是当电子注的速度比增大到一定值时,电子注的性能就会变得不太稳定。     

基于一种新型杂化阳极修饰层的高效有机电致发光器件

设计了基于Bphen∶LiF、Al和MoO₃的杂化电荷注入层,并将其应用于有机电致发光器件中。实验研究表明,这种杂化层作为阳极修饰层是非常有效的,它可以增加器件中载流子注入的平衡性,提高器件的性能。相对参考器件,基于杂化阳极修饰层的电致发光器件的最大电流效率和最大功率效率均提高1.3倍左右。我们对器件性能及其提高的机理进行了分析。     

A buffer direct injection and direct injection readout circuit with mode selection design for infrared focal plane arrays

This paper proposes a solution to the excessive area penalty associated with traditional buffer direct injection (BDI) for single pixel. The proposed solution reduces the area and power consumption of BDI to combine the direct injection (DI) within a shared architecture, while a dual-mode readout circuit expands the functionality and performance of the array readout circuit of infrared sensor. An experimental array of 10 × 8 readout circuits was fabricated using TSMC 2P4M 0.35 μm 5 V technology. Measurements were obtained using a main clock with a frequency of 3 MHz and power consumption of 9.94 mW. The minimum input current was 119 pA in BDI and 1.85 pA in DI. The signal swing was 2 V, the root mean square noise voltage was 1.84 mV, and the signal-to-noise ratio was 60 dB. This approach is applicable to mid- and long-band sensors to increase injection efficiency and resolution.     

Laser Blow-Off Injected Impurity in HL-2A Tokamak

Transient perturbation methods are most appropriate to study particle transport in tokamaks. Two most commonly used techniques of impurity injection are laser blow-off and gas puffing. Short bursts of impurities, injected using the laser blow-off injection technique, are among other transient perturbation methods, undoubtedly best suited to study impurity transport The injection time and the amount of injected material can be controlled in order to study a certain phase of the discharge with a minimum perturbation of the plasma parameters. Furthermore, the source is of very short duration and thus provides an experimentally more direct measure of impurity transport.     

The Progression of the Impurities Injected into the Plasma Following by Soft X-ray Arrays on HL-2A Tokamak

Small amounts of metallic impurity is injected by laser blow-off on HL-2A tokamak in order to study transport phenomena. The particle transport is interpretated along     

用CCD相机观测HL—1M弹丸消融过程

利用高速ＣＣＤ相机拍摄了ＨＬ－１Ｍ等离子体中注入氢弹丸时的Ｈａ辐射照片。得到的弹丸不同形状消融云照片表明：弹丸轨迹发生弯曲和出现条纹。通过对照片的处理获得了辐射光强的空间分布、弹丸的速度与轨迹,分析了弹丸与等离子体相互作用的物理机制,为进一步在弹丸注入条件下用ＣＣＤ测量等离子体局部磁场和电流分布打下了基础。     

Degradation of gate-recessed MOS-HEMTs and conventional HEMTs under DC electrical stress

The performance degradation of gate-recessed metal–oxide–semiconductor high electron mobility transistor(MOSHEMT) is compared with that of conventional high electron mobility transistor(HEMT) under direct current(DC) stress,and the degradation mechanism is studied. Under the channel hot electron injection stress, the degradation of gate-recessed MOS-HEMT is more serious than that of conventional HEMT devices due to the combined effect of traps in the barrier layer, and that under the gate dielectric of the device. The threshold voltage of conventional HEMT shows a reduction under the gate electron injection stress, which is caused by the barrier layer traps trapping the injected electrons and releasing them into the channel. However, because of defects under gate dielectrics which can trap the electrons injected from gate and deplete part of the channel, the threshold voltage of gate-recessed MOS-HEMT first increases and then decreases as the conventional HEMT. The saturation phenomenon of threshold voltage degradation under high field stress verifies the existence of threshold voltage reduction effect caused by gate electron injection.