基于PCAS的Tektronix示波器与EPICS通信研究

现代大型实验物理和加速器装置中,高端示波器被越来越广泛地应用于信号采集和测量方面。EPICS是应用于大型实验物理和加速器控制系统的组态软件工具集,PCAS是EPICS用来端接EPICS异构系统的一种手段,已在多个加速器和EPICS工具上得到应用。论文介绍了利用PCAS把Tektronix示波器接入EPICS的方法。基于该方法,实现了通过EPICS对BEPCⅡ电子枪触发信号抖动值的实时监测。     

基于HPI的通用ATCA EPICS设备支持模块开发

先进的电信计算平台（ATCA）因其高可靠性在反应堆仪控系统中得到应用,但其系统管理仍停留在厂商提供私有的管理软件,可读性和可操作性较差。本文在实验物理及工业控制系统（EPICS）下开发了一种基于硬件平台接口（HPI）协议的通用ATCA设备支持模块,其可通过HPI协议将ATCA机架内的风扇、温度传感器、电源和单板等信息传给操作员界面,操作员可远程监控和管理ATCA系统,实现远程配置。开发基于HPI的EPICS设备支持模块对于提高钍基熔盐堆仪控系统的可靠性具有重要意义。     

EPICS在RTEMS上的实现

EPICS是用于开发分布式实时控制系统的软件工具包,广泛应用于粒子加速器、高能物理实验、天文望远镜等大型科学实验设备的控制系统的开发。阐述了EPICS在RTEMS上实现的原理和方法,介绍了以RTEMS作为前端IOC的实时操作系统而实现的EPICS样机系统,为EPICS的研究和EPICS在实际项目中的应用提供了一种新的IOC操作系统平台。     

EPICS数据包捕获分析工具开发及其应用

加速器控制网内EPICS数据包的捕获分析,可对控制网内出现的与EPICS CA通信相关的问题进行快速定位,还可用于监测EPICS IOC活动状态以及记录对EPICS PV的写操作日志。使用PCAP应用接口可开发出捕获特定数据包的应用程序。本文介绍了基于PCAP接口开发的EPICS数据包捕获分析工具—cacap以及cacap在CSNS加速器控制系统中的应用。     

基于EPICS的数据采集系统

本文介绍了在加速器控制系统和束流测量系统中广泛应用的EPICS开发平台，并在Redhat 6.2操作系统上建立了一个基于EPICS的数据采集系统，利用该系统实现了束流位置探头的快速标定。     

基于RTEMS操作系统的EPICS应用研究

目前,世界上各大加速器广泛采用基于以太网的分布式控制系统组态软件包EPICS构建控制系统.EPICS早期版本是基于实时操作系统VxWorks发展起来的.EPICS国际合作组正致力于支持源码开放,免费的操作系统RTEMS,并准备将RTEMS推广到EPICS3.14新版本中.文章阐述了RTEMS的发展、特点,对比了几种常见的实时操作系统的性能,建立了基于Mlotorola MVME5500的RTEMS操作系统以及EPICS在RTEMS上的应用实例.     

基于Web的BEPCⅡ磁铁电源的远程监控系统

目前,国内外加速器控制均采用基于以太网的分布式体系结构,控制软件绝大多数采用组态软件包EPICS。而基于Web的远程监控,在当前国际加速器控制领域是一前沿课题。本工作研究了EPICS系统与Web的接口技术,并在此基础上实现了基于Web的BEPCⅡ磁铁电源的远程监测。     

EPICS PCAS及其在BEPCII上的应用

非EPICS应用程序接入EPICS是加速器控制中的常见问题,EPICS提供了一组名为PCAS类接口,用于把非EPICS应用程序接入到EPICS中。为方便使用PCAS开发应用程序,本文开发了基于PCAS的动态链接库pcasdll,并对其CA访问响应性能进行了测试。另外,介绍了基于此动态链接库开发的BEPCII电子枪定时插件温度数据采集系统。     

CAN总线在北京正负电子对撞机直线加速器控制系统中的应用

以CAN总线在北京正负电子对撞机(BEPC)直线加速器控制系统中的应用为例,介绍了CAN总线的特点,系统结构以及基于VME总线的CAN接口卡在实验物理和工业控制系统(EPICS)中的软件设计。CAN总线已成功地在北京正负电子对撞机直线加速器控制系统的磁铁电源控制EPICS样机系统中得到应用,取得了满意的结果。     

基于MicroTCA的EPICS控制系统研究

本文介绍了现代加速器控制系统的发展趋势,针对未来加速器控制系统的高数据传输率、低延时的要求,研究了基于MicroTCA技术的EPICS控制系统,开发了基于EPICS平台的、具有完整功能的MicroTCA样机系统。此系统包括硬件搭建、Linux系统设备驱动开发、基于EPICS的设备支持层和实时数据库。此外,本文采用CSS开发了功能完备的OPI,且对该系统的性能进行了测试,为该系统的实际应用打下了基础。     

Preparation of Zn/TiO2 powder and its photocatalytic performance for oxidation of P-nitrophenol

Zn-doped TiO2 catalysts were prepared using a sol-gel method and characterized by XPS,UV-Vis, BET, XRD in this study. Under the irradiation of simulant sunlight, the photocatalytic activity for the degradation of p-nitrophenol was studied too. After irradiation for 2.5 h, the degradation percentage of p-nitrophenol could rise to more than 80 %. The results showed that the spectrum absorption band edge of Zn/TiO2 powder does not broaden obviously comparing with pure TiO2 powder. Zinc exists as Zn （11）. When calcined at 973 K, there is a new phase as ZnTiO3 in Zn/TiO2 catalyst. The order of photocatalytic activity of Zn/TiO2 catalysts calcined at different temperatures for p-nitrophenol is 773 K 〉 673 K 〉 873 K 〉 573 K 〉 973 K and the photocatalytic activity of Zn/TiO2 catalyst calcined at 773 K is better than TiO2 catalysts heated at the same temperature, and outclasses that of commercial TiO2 catalyst. It also showed that the photocatalytic degradation of p-nitrophenol follows first-order kinetics under the irradiation of simulant sunlight.     

Current status of radiation therapy for prostate cancer

Radiotherapy for the treatment of prostate cancer has been extensively explored in the past. Along with the comprehensive understanding of the biology of prostate cancer and rapid advances in terms of technology, the out- come of treatment for the patients with prostate cancer has improved. The authors review radiotherapy as the primary treatment for the disease, with particular emphasis on the technological advances from both the radiobiological and radiophysics aspects. Nonconventional fractionated irradiation like hyper- or hypo-fractionation has been imple- mented in the clinic, the final results still need to be confirmed in the future. Technological advances like IMRT, IGRT, in the last two decades have significantly improved the delivery of external radiotherapy to the prostate. This has re- sulted in an overall increase in the total dose that can be safely delivered to the prostate, which has led to modest im- provements in the biochemical outcome. However, establishing the standard therapy for prostate cancer remains con- troversial. It is hoped that the next decades will bring continued advances in the development of biologicals that will further improve current clinical outcomes.     

The control system for SSRF injection and extraction

This paper introduces the injection and extraction control system design for SSRF,which is a distributed control system aimed at stability and reliability of the pulse power supplies,PPS(Personnel Protection System)and MPS(Machine Protection System).The hardware environment is mainly based on PLC(Programmable Logic Con- troller),and ARM(Advanced RISC Machine)is also applied for studying stability of the power supplies.WinCC and EPICS(Experimental Physics and Industrial Control System)have been selected as the platforms of SCADA(Super- visory Control and Data Acquisition).For unifying the interfacing to the control computer,all front-end equipments are connected via Industrial Ethemet.     

水平管内含空气蒸汽强制对流冷凝换热模型研究

为研究含空气蒸汽在水平管内强制对流冷凝换热特性,基于对传热传质过程的分析,建立了管内为环状流与波状流条件下的流动冷凝换热模型。从潜热、显热和液膜3个环节对整个换热过程进行建模,最终得到计算局部冷凝换热系数的理论关系式。模型预测结果与实验数据的对比表明,二者相对偏差在±20%以内,验证了该换热模型的准确性与适用性。通过进一步的研究发现：从换热管入口至出口,随着冷凝的进行,管内换热主要热阻由液膜热阻向气液界面的凝结热阻转变;主流气体对流换热过程基本可忽略。     

Investigations on landmine detection by BF3 detector

Experiments were carried out to investigate the possible use of neutron backscattering for the detection of polyethylene (PE) sample buried in the soil. In detection of landmine by neutrons, the neutron detector and its shield play an important role. In this paper, the effects of graphite, heavy water, polyethylene and boric acid moderators on the flux of back scattered neutrons were investigated. We have also experimentally verified the effect of BF3 detector shield and obtained good agreement with theory.     

Web Services interface of SSRF archive data analysis system

Accelerator database stores various static parameters and real-time data of accelerator. SSRF (Shanghai Synchrotron Radiation Facility) adopts relational database to save the data. We developed a data retrieval system based on XML Web Services for accessing the archive data. It includes a bottom layer interface and an interface applicable for accelerator physics. Client samples exemplifying how to consume the interface are given. The users can browse, retrieve and plot data by the client samples. Also, we give a method to test its stability. The test result and performance are described.     

Assessment of radioactivity levels in some oil samples from the western desert, Egypt

Distributions of natural gamma-emitting radionuclides were determined in 93 oil samples collected from some petroleum fields in the western desert of Egypt. The radioisotope activities in the area under investigation lay in the range of (21 ± 4) to (38 ± 13) Bq?L-1 for 226Ra, (9 ± 2) to (15 ± 5) Bq?L-1 for 232Th, and (154 ± 28) to (303 ± 54) Bq?L-1 for 40K. The mean values were 27, 12, and 201 Bq?L-1, respectively. Among oils, variations in radionuclide ac- tivities could be on account of differences in TDS, HCO3, and Ba, with high or low pH. In this environment, oil prop- erties differently affected the mobilization of natural radionuclides. The range of 226Ra variation had been compared with available data from other countries. The calculated absorbed dose rate ranged from 22.33 to 32.66 nGy?h-1 in lo- cation (B) and (E) respectively, which was less than the accepted value.     

Preparation and properties of 117m Sn(IV)-TTHMP in in-vitro and in small animals

In this work,TTHMP was synthesized and labelled with 117m Sn.The preparation conditions,stability and lipophilicity of 117m Sn(IV)-TTHMP were investigated.Biodistribution of the complex in rabbits and mice was studied.It was found that the quantity of TTHMP and pH value of the prepararion solution had vital effects on the labeling yield of 117m Sn(IV)-TTHMP.It was also found that 117m Sn(IV)-TTHMP was hydrophilic and stable at room temperature and 37℃ in open air 117m Sn(IV)-TTHMP showed unexpectedly high bone uptake and bone-to-blood ratio in the animals.This made it potentially useful as an reagent for skeletal scintigraphy and radiotherapy of bone tumors.     

Gamma radiation levels in the ambient environment of the QNPP Base

Monitoring results of gamma dose rate level in 1992～2004 in the ambient environment of the Qinshan Nuclear Power Plants(QNPP)Base,the northeast of Zhejiang Province,are reported in this paper.It is shown that the gamma dose rate of five monitoring sites of 2.5 km to QNPP Base is 84～113 nGy/h,with an average of 96 nGy/h in the 13 years.The average value is close to the background level of 93 nGy/h prior to operation of the QNPP Base,and is lower than the monitoring result of 101 nGy/h at the reference site in Hangzhou City.Within 50 km from the QNPP Base,the cumulative dose rate of the thermoluminescent dosimeter(TLD)is 90 nGy/h,which is lower than the back- ground level of 111 nGy/h.     

The role of AGFA high-energy CR in the calibration and quality control of multileaf collimators （MLC）

Linear accelerators equipped with multileaf collimators （MLC） are becoming more common and are widely used in the intensity-modulated radiotherapy （IMRT）. There is an imperative need to ensure the commissioning specification of the linear accelerators for the sake of quality assurance （QA） and quality control （QC）. This paper is aimed to investigate the role of AGFA high-energy CR （Computed Radiography） in calibrating dynamic multileaf collimators and evaluating the accuracy of the leaf position. The result shows that AGFA high-energy CR can easily and conveniently be used to calibrate MLC and verify its position. Hence, the application of AGFA high-energy CR is proved to be an accurate and time-saving method for routine MLC QC, especially when MLC calibration adjustments are required.