上海软X射线自由电子激光装置直线加速器束流位置测量系统研制

上海软X射线自由电子激光装置（SXFEL）作为中国第一台工作在软X射线波段的第四代光源,其产生的激光具备短波长、全相干、超高亮度、超短脉冲长度等优点,预期将会在基础科学研究领域中发挥出重要的作用。基于直线加速器的特点和需求,在SXFEL的注入器与直线加速段上选择了条带型束流位置测量系统（SBPM）作为束团位置测量工具。该系统由SXFEL束测团队自主研发设计,由条带探头、前端信号调理电子学与专用数字信号束流位置处理器（DBPM）组成,系统设计上借鉴上海同步辐射光源（SSRF）的同类型设备,并根据SXFEL的特点做了进一步的优化,束流实验结果表明该系统位置测量系统分辨率好于5.7 μm@188 pC,达到国际先进水平,满足了SXFEL注入器和直线加速器段对束流位置测量分辨率的设计要求。     

数字束流位置探测器通道自动增益校准方法的研究与实现

在现有硬件基础上,基于BPM测量准确度的需求,在自制的电子学FPGA芯片内,通过Verilog语言实现了一种数字BPM采样数据增益自动校准的设计。首先介绍了自动增益校准模块的系统总体设计;然后对模块的实现方法做了详细说明,设计并搭建了ADC数据自动增益校准测试平台以验证自动增益较准模块的功能;最后介绍了该设计在BPM通道标定中的应用。实验结果表明,该方法可以实现4通道增益一致,使ADC采样后的数据幅度相同,有效解决了由通道增益不一致引起的测量偏差,以及工程应用中ADC数据幅度校准工作量大且难于操作的问题,将在BPM系统通道自动标定中发挥重要作用。     

基于Web的实时漆包线材生产设备监控平台设计

为了实现漆包机生产的远程监控,设计了一款基于Web的实时漆包机远程监控平台。该平台使用模块化,可扩展的设计方案,采用了Spring MVC的后台Web应用程序框架,基于Modbus协议的数据交互,Ajax方式的网络数据异步提交以及无刷新的图表显示技术。传统的监控平台只能通过以太网在企业内部访问,而该平台可接入互联网,可实现随时随地通过电脑及或者移动终端对生产设备各部分的温度点、电机风机转速、耗电量统计的实时监视,对温度的上下限及电机转速进行远程控制,接收设备状态异常的实时报警,数据存储分析。实验测试表明,该平台的实时性和稳定性均能达到车间生产的要求。     

Upgrade of beamline BL08B at Taiwan Light Source from a photon‐BPM to a double‐grating SGM beamline

During the last 20 years, beamline BL08B has been upgraded step by step from a photon beam‐position monitor (BPM) to a testing beamline and a single‐grating beamline that enables experiments to record X‐ray photo‐emission spectra (XPS) and X‐ray absorption spectra (XAS) for research in solar physics, organic semiconductor materials and spinel oxides, with soft X‐ray photon energies in the range 300–1000 eV. Demands for photon energy to extend to the extreme ultraviolet region for applications in nano‐fabrication and topological thin films are increasing. The basic spherical‐grating monochromator beamline was again upgraded by adding a second grating that delivers photons of energy from 80 to 420 eV. Four end‐stations were designed for experiments with XPS, XAS, interstellar photoprocess systems (IPS) and extreme‐ultraviolet lithography (EUVL) in the scheduled beam time. The data from these experiments show a large count rate in core levels probed and excellent statistics on background normalization in the L‐edge adsorption spectrum.     

太阳能驱动全天候监控系统的实验设计

研发了一套太阳能全天候监控系统设计性实验。该实验通过对太阳能电池板基本物理性能的测定,了解其工作原理,然后选择合适的控制器件与负载,设计电路,最后形成一套由太阳能电池板提供能量,实现全天候监控的应用系统。该实验不仅能够作为设计性实验用于大学物理实验,而且可以应用于许多工程领域。     

流动注射-分光光度法测定自来水中游离氯的研究

设计了游离氯流动注射自动在线检测仪,并研究了仪器的最佳测试条件.该仪器采用改进的N,N-二乙基-1,4-苯二胺(DPD)比色原理,通过流动注射进样技术,结合光电转化、数字信号处理及自动化控制技术,克服了DPD分光光度法中手工操作的缺陷,实现了样品分析的自动化.结果证明,此系统的试剂用量少、测定范围宽(0.05～6.00...     

合肥光源直线加速器BPM系统的研制和测量

合肥光源直线加速器新改造的BPM系统已经安装, 并做了在线的束流位置测量实验. 本文介绍该BPM系统的结构、作为系统核心部分的信号处理模块以及离线标定的实验结果和在线应用的实验结果, 表明该BPM系统具有不小于40dBm的动态范围, 不大于100μm的束流位置分辨率, 水平方向和垂直方向分别具有1.61dB/mm和1.51dB/mm的灵敏度. 校正铁强度与BPM读数关系的实验, 表明该BPM系统能正确地反映束流的位置变化情况, 并且确定了校正铁在水平方向和垂直方向的校正系数分别为0.46mm/A和0.58mm/A, 校正铁设置为默认值时该BPM处的束流中心水平位置和垂直位置分别为0.83mm和－0.57mm.     

Measuring particle size-dependent physicochemical structure in airborne single walled carbon nanotube agglomerates

As-produced single-walled carbon nanotube (SWCNT) material is a complex matrix of carbon nanotubes, bundles of nanotubes (nanoropes), non-tubular carbon and metal catalyst nanoparticles. The pulmonary toxicity of material released during manufacture and handling will depend on the partitioning and arrangement of these components within airborne particles. To probe the physicochemical structure of airborne SWCNT aggregates, a new technique was developed and applied to aerosolized as-produced material. Differential Mobility Analysis-classified aggregates were analyzed using an Aerosol Particle Mass Monitor, and a structural parameter Γ (proportional to the square of particle mobility diameter, divided by APM voltage) derived. Using information on the constituent components of the SWCNT, modal values of Γ were estimated for specific particle compositions and structures, and compared against measured values. Measured modal values of Γ for 150 nm mobility diameter aggregates suggested they were primarily composed of non-tubular carbon from one batch of material, and thin nanoropes from a second batch of material – these findings were confirmed using Transmission Electron Microscopy. Measured modal values of Γ for 31 nm mobility diameter aggregates indicated that they were comprised predominantly of thin carbon nanoropes with associated nanometer-diameter metal catalyst particles; there was no indication that either catalyst particles or non-tubular carbon particles were being preferentially released into the air. These results indicate that the physicochemistry of aerosol particles released while handling as-produced SWCNT may vary significantly by particle size and production batch, and that evaluations of potential health hazards need to account for this. Disclaimer: The mention of any company or product does not constitute an endorsement by the Centers for Disease Control and Prevention. The findings and conclusions in this paper are those of the authors and do not necessarily represent the views of the National Institute for Occupational Safety and Health.     

基于EPICS的CSRe束流诊断控制系统升级

兰州重离子加速器(HIRFL)冷却存储环的实验环（CSRe）提供高品质的束流用于高精度的质量测量、原子物理等实验研究,实现束流参数的准确测量是进行物理实验的前提保障。目前,CSRe加速器控制系统已升级为EPICS架构。介绍了基于EPICS的束流诊断控制系统现状,并利用升级后的控制系统测量了束流相关参数。其中,束流位置系统能够测量注入束流的逐圈位置信息,测量结果发现束流在注入过程中存在一定程度的震荡,影响注入效率。流强测量系统通过高分辨的数据采集卡实现对DCCT信号的精确测量,同时增加了D事例触发功能。升级后的控制系统,可以实现束流参数的测量,并集成于加速器控制系统的EPICS CSS界面。     

14MeV中子引起的核反应截面测量中监督反应的研究

讨论了14MeV中子引起的核反应截面测量中监督反应对测量结果的影响,同时列出了常用的一些监督反应及参数,利用截面的评价值给出了一些监督反应的截面随中子能量变化的关系曲线,并对^27Al（n,p）^27Mg反应做了定性分析,说明了监督反应的选取对反应截面测量的重要性。 It was discussed in this article that the effects of different monitors in the cross section measurements of nuclear reactions induced by 14 MeV neutrons, at the same time some monitors and correlative parameters were listed. The excitation functions of monitors are taken from the evaluatied cross sections, and a qualitative analysis has been performed for ^27Al（n,p） ^27Mg reaction. It indicates that the choice of monitor is very important for cross section measurements