基于印刷线路板技术的复合气体探测器

将当前先进的PCB加工技术用于制作微条气体探测器(MSGC),并结合微电子加工技术制作电子倍增器(GEM),可以制作性能优越价格低廉的复合式位置灵敏探测器.论文从气体探测器工作原理出发,分析了各种类型气体探测器的优缺点,并根据当前国内的微电子加工技术,设计制作了MS-GC+ GEM复合式气体探测器.随着PCB精加工技术的进步,性能更优越可靠、更易加工的气体探测器很快将问世.     

蓬勃发展的位置灵敏气体探测器

介绍了近年来气体位置灵敏探测器的发展,简要描述了几种新型的高位置分辨、高计数率的探测器：MSGC、MGC、MICROMEGAS、GEM等。     

气体电子倍增器的研制及性能测试

气体电子倍增器(GEM)以其独特的性能在辐射探测器领域得到了广泛的应用,对50μm厚聚酰亚胺(kapton)薄膜利用真空热蒸发和激光掩膜打孔法制作GEM膜,孔径100μm,孔距223μm,并封装流气式探测器,有效探测面积3mm×3mm。5.9keV55F e X射线测量了GEM在不同高压和混合气体比例时的脉冲幅度分布情况。讨论了高压和气体比例对探测器计数率和能量分辨率的影响。结果表明GEM具有较高的信噪比,能量分辨率可达18.2%。     

带增益的气体探测器读出ASIC的研制

设计了用于带增益的气体探测器比如GEM、RPC等读出的ASIC,实现对探测器信号的放大、成形和对后续实时采样ADC的驱动电路.电荷增益和成形时间可调,有利于探测器不同增益下性能的研究,也扩展了芯片的应用范围.由于成形电路引入的噪声变得显著,在低电荷增益下,ENC会随增益下降而增加.芯片采用Chartered 0.35μm2P4M CMOS工艺,论文介绍了芯片的详细设计和仿真结果.     

大面积GEM膜制作方法研究

正近年来气体电子倍增器(GEM)成为新一代微结构气体探测器的主要发展方向,在国际上得到迅速发展。作为整个GEM探测器的核心的大面积GEM膜研制,在我国微结构探测器研究领域有着重要需求。目前我国参加的重大国际合作CERN LHC上ALICE实验和JLab 12GeV升级SoLID谱仪的建设都将用到GEM探测器。通过与CERN合作,掌握了制作大面积GEM膜的关键技术,确定研制大面积GEM膜需解决的关键问题,包括如何实现GEM膜制作过程中从掩膜板到GEM原膜精确的图像转移和如何实现大面积GEM膜的均匀性。并由此确定GEM膜制作的     

基于粒子-蒙特卡洛模型的气体电子倍增探测器的研究

采用粒子一蒙特卡罗模型(Particle in Cell-Monte Carlo Collision,PIC-MCC)对气体电子倍增探测器(Gaselectron multiplier,GEM)的倍增放大过程进行了模拟,这对更好的理解和把握GEM的物理机理具有重要的意义.在电场分析的基础上,从GEM空间粒子数和粒子的空...     

应用于气体电子倍增器的电子学板研制

气体电子倍增器（GEM）电子学板（GEB）在大面积GEM探测器系统中起重要作用。为满足大面积GEM探测器系统中高速电子学信号的传输、实现电磁屏蔽及为前端电子学提供电源等需求，本文设计了8层结构的GEB，并对该GEB原型进行了电气性能、机械兼容性、信号传输和噪声测试。测试结果显示，本文所设计的GEB在320 Mb/s信号传输速度下的误码率小于10^-13，在保证信号高速性和完整性的基础上能成功传输前端电子学信号；通过采用叠层对称式设计克服了大面积GEB生产时弯曲程度高的困难，生产的GEB原型弯曲高度降低了2/3，平均弯曲高度为1 mm，增强了前端电子学在探测器系统中的运行稳定性。     

一种新的气体电子倍增模式的研究

介绍了一种新的气体放大器件--GEM,制作了一个有效面积为100mm×100mm的GEM+MWPC的模型.用5.9 keV的X射线源测量它的气体倍增系数,并研究了不同气体比例(Ar/CO2)下GEM的放大的性能.GEM的放大倍数可达到94倍.     

GEM探测器公共触发信号的优化研究

采用模拟和实验方法研究了GEM探测器自身提供的公共触发信号的特性,得到触发信号的极性和幅度与探测器感应区的场强密切相关;通过对探测器在产生不同极性触发信号的配置高压下的好事例率、位置分辨率以及成像性能的测试分析,得出负触发信号与正触发信号一样均可以作为探测器的有效公共触发信号,不会影响探测器的性能。为GEM探测器适应不同工作条件而采用不同的公共触发高压设置提供参考。     

Mark—J气体系统

就工作方式而言,气体系统可分为循环式和非循环式两类。前者适用于气体探测器总容积宠大、运行时间长、气体消耗大的场合,通过气体净化、回收循环使用,大大降低了费用,这种模式对探测器气密要求较高。后者则是工作气体经探测器后直接逸入大气,对气密要求较低,但仅适用于气体消耗不大的场合。     

200 MW 模块式高温气冷堆回热循环系统热力学设计研究

高温气冷堆是一种新型的反应堆堆型,它可以提供高达900 ℃的高品质热源,为了充分利用这一资源,需要在核能利用中引入气体轮机这一常规工业中的先进技术.给出了200 MW 高温气冷堆的气体轮机回热循环系统的设计研究.     

Maximum scintillation yields in NaI(Tl) and CsI(Tl) crystals estimated from the scintillation model for liquid rare gases

The maximum scintillation yields in NaI(Tl) and CsI(Tl) crystals were estimated theoretically by applying the scintillation model for liquid rare gases to crystal scintillators. Average energies required to produce one scintillation photon in the maximum scintillation yield, W_so, were estimated to be 10.6 ± 0.3 or 11.6 ± 0.3 eV for NaI(Tl) and 11.6 ± 0.3 or 12.5 ± 0.3 eV for CsI(Tl). The new experiment on scintillation yields gives W_so of 10.8 ± 2.0 eV for NaI(Tl) and 11.3 ± 2.1 or 9.3 ± 1.7 eV for CsI(Tl). The values show good agreement with the theoretical estimations. These results demonstrate that the scintillation model in liquid rare gases is applicable to inorganic scintillators such as NaI(Tl) and CsI(Tl) crystals.     

用于短寿命核素研究的简单的气体传输系统

气体传输系统是研究短寿命核衰变的一种重要的实验技术。由于周期表中大多数元素具有高的粘滞系数,这些元素的传输需用气体喷咀技术,特别是氦喷咀技术。对于气体元素或某些能形成稳定气体的化合物元素,由于它们的粘滞系数比较低,运用一般的气体(空气)能把它们从高辐射场位置有效地传输到低本底区。气体的传输速度在亚声速范围以内,对于10     

微阴极条感应室

微阴极条感应室是近年来发展起来的一种高位置灵敏气体探测器，并被应用到世界上最大加速器LHC的大型探测器LHC－b上，比较详细地描述了探测器的基本结构，工作原理和主要性能。     

Experimental Study on the Velocity and Efficiency Characteristics of a Serial Staged Needle Array-Mesh Type EHD Gas Pump

The ionic wind has good application prospects in the fields of air flow control and heat transfer enhancement. The key for successful applications is how to imp...     

高温气冷堆石墨材料的疲劳裂纹扩展综述

迄今为止,各国的高温气冷堆均采用石墨作为其堆芯活性区及反射层的主要结构材料。由于堆内的高温高辐照环境,石墨构件一般承受较高的热应力及辐照应力,这些应力的循环变化将引起疲劳载荷。     

Overview of the J-TEXT progress on RMP and disruption physics

The J-TEXT tokamak has been operated for ten years since its first plasma obtained at the end of 2007. The diagnostics development and main modulation systems, i.e. resonant magnetic perturbation (RMP) systems and massive gas injection (MGI) systems, will be introduced in this paper. Supported by these efforts, J-TEXT has contributed to research on several topics, especially on RMP physics and disruption mitigation. Both experimental and theoretical research show that RMP could lock, suppress or excite the tearing modes, depending on the RMP amplitude, frequency difference between RMP and rational surface rotation, and initial stabilities. The plasma rotation, particle transport and operation region are influenced by the RMP. Utilizing the MGI valves, disruptions have been mitigated with pure He, pure Ne, and a mixture of He and Ar (9:1). A significant runaway current plateau could be generated with moderate amounts of Ar injection. The RMP has been shown to suppress the generation of runaway current during disruptions.     

高气压监控漂移管幅度性能的实验研究

对高气压监控漂移管在不同气压下工作性能进行了研究。对测得的气体增益和高压关系与有关理论公式进行了比较;对输出脉冲信号与粒子径迹到阳极丝距离的依赖关系进行了研究,并用带电粒子在漂移管内所产生径迹的原初电离电子漂移过程中的聚集效应进行分析。     

Long-Term Integrity of Waste Package Final Closure for HLW Geological Disposal, (V) Applicability of MAG Welding Method to Overpack Final Closure

Overpack, a high-level radioactive waste package for Japan's geological disposal program, is required for preventing the sealed vitrified waste from contact with groundwater for 1,000 years. In this study, metal active gas (MAG) welding, a typical arc welding method, was evaluated for its applicability in sealing a carbon steel overpack lid with a thickness of 190 mm. Welding conditions and parameters were examined with multilayer welding for three different groove depths. Welded joint tests including the observation of macro- and microstructures were conducted, and mechanical properties were within tentatively applied criteria. Measurements and numerical calculations for residual stress were also conducted, and residual stress distribution tendencies were discussed. These test results were compared with those previously reported for tungsten inert gas welding (TIG) and electron beam welding (EBW). MAG welding possesses the potential to complete overpack lid closure with a maximum groove depth of 190 mm, but the applicability of MAG welding to overpack final closure should be discussed from the viewpoint of the presence of slag inclusions possibly induced in the weld metal.     

Experiments on Gas Jet in the Wendelstein 7-AS Stellarator

Wendelstein 7-AS (W7-AS) pertains to an advanced helical stellarator. A new fuelling method, the supersonic molecular beam injection (SMBI, named Gas Jet in Germany) system was installed in W7-AS in May 2001 as a cooperation research item co-supported by the National Nature Science Foundation of China and the Max-Planck Institute of Plasma Physics, Garching, Germany. The experiments of the gas jet with hydrogen or deuterium on W7-AS were implemented. The experimental results exhibit the following features such as high fuelling efficiency, stable high-density plasmas and reduction of the recycling fluxes from the vessel wall during injection. These crucial points show that the new fuelling method can be applied to long and stable discharges.