地表空气中^7Be浓度

杭州附近地区的测量结果表明，地表空气中＾７Ｂｅ的浓度全年平均为４．６±２．０ｍＢｑ·ｍ＾－３，比ＵＮＳＣＥＡＲ的报告值高出５０％－８０％。其中１０、１１、１２月份的均值最高，达６．８±１．１ｍＢｑ·ｍ＾－３；２、６、７月份的均值最低，在２．０±０．１７ｍＢｑ·ｍ＾－３；４、５月份的浓度接近于全年平均值；表现出明显的与降水有关的季节性变化，而未显示出ＵＮＳＣＥＡＲ报道的与平流层沉降有关的春天最高、晚     

肾脏显像剂^99mTc—L,L—EC的初步临床应用研究

初步总结了７５例＾９９ｍＴｃ－Ｌ，Ｌ－ＥＣ肾动态显像；１５名正常志愿肾脏显像清晰，靶／非靶组织比较高，＾９９ｍＴｃ－Ｌ，Ｌ－ＥＣ在肾脏摄取与排泄迅速，平均左、右肾达峰时间分别为３．０７±０．５９、３．２２±０．７５ｍｉｎ，肾内放射性７３％以上被清除；６０例病人显像结果与临床诊断或／和其它检查符合性好。初步结果预示：＾９９ｍＴｃ－Ｌ，Ｌ－ＥＣ临床肾功能显像应用前景乐观。     

用符合弹性前冲法测量硅中的氧含量及其分布

采用２７ＭｅＶ的＾１２Ｃ５＾５＋作为入射粒子，采用符合弹性前冲方法测量了５．６μｍ的硅样品中氧的含量及其深度分布。实验结果表明，采用＾１２Ｃ与＾１６Ｏ符合弹性前冲方法分析硅样品中的氧，其最小探测限可达２０×１０＾－６，深度分辨率为－４５０ｎｍ。该方法对于厚样品，尤其比常规弹性前冲优越。     

北京HI—13串列加速器质谱计测定^36Cl的研究

描述了中国原子能科学研究院的基于ＨＩ－１３串列加速器建立的加速器质谱计装置和测定＾３６Ｃｌ的实验方法。利用这台加速器质谱计测定＾３６Ｃｌ／Ｃｌ同位素原子比值的灵敏度已好于３×１０×－１５，对地下水，盐湖和铀矿石样品中的＾３１Ｃｌ进行了测定，这些样品的＾３６Ｃｌ／Ｃｌ同位素比为１．２×１０×－１２－２．２×１０＾－１４。     

氧化钆中稀土和非稀土杂质元素的ICP—AES法测定

本文介绍了电感合等离子体原子发射光谱法测定氧化钆中１８种元素，经对元素光谱干扰和基体效应的探讨发现，当溶液中氧化钆浓度为５ｍｇ·ｍＬ＾－１时，本法测定下限在６×１０＾－５～１×１０＾－３μｇ（ｇ·Ｇｄ２Ｏ３）＾－１之间。加入回收率在８２％－１０９％之间；相对标准偏差优于±６．９％。     

电离辐射作用后粒—巨噬细胞修复的特性

运用粒－巨噬细胞集落（ＣＦＵ－ＧＭ）体外培养技术，观察了受次致死剂量＾６０Ｃｏγ射线照射的小鼠骨髓ＣＦＵ－ＧＭ的修复能力。实验测得正常小鼠每根股骨中ＣＦＵ－ＧＭ的总数和骨髓有核细胞总数分别为４．８９×１０＾４和２．４×１０＾７，经６Ｇｙ剂量照射后第３ｄ，两计数值分别下降到正常值的０．８％和４％，照射后第５ｄ出现回升。骨髓有核细胞计数和外周血白细胞数与ＣＦＵ－ＧＭ的变化规律相一致。     

煤,煤灰,煤渣及土壤中^210Pb的测定

研究了煤、煤灰、煤渣和土壤样品中＾２１０Ｐｂ的测定方法，分析程序主要包括ＨＣｌ浸取，阴离子交换分离，ＰｂＳ沉淀纯化和＾２１０Ｂｉ测量。分析１０ｇ煤时，检测限为７．６×１０＾－４Ｂｑ／ｇ；分析５ｇ煤灰，煤渣或土壤时，检测限均为１．５×１０＾－３Ｂｑ／ｇ。测得煤、煤灰、煤渣和土壤样品中＾２１０Ｐｂ含量分别为０．０３１６±０．００９７、０．０７１２±０．０７６０、０．０１０９±０．００３５和０．０３５５     

^99Tc^m—ECD脂溶性成分在血液中的变化规律

＾９９Ｔｃ＾ｍ－ＥＣＤ弹丸注射后，血中放射性浓度迅速增高，１ｍｉｎ时达到峰值，全血脂溶性分数Ｎｗ在注射后０．５ｍｉｎ时最大，随着时间的推移Ｎｗ快速变小。１ｍｉｎ时Ｎｗ时为０．７１±０．０６，＾９９Ｔｃ＾ｍ－ＥＣＤ的全血时间变化常数Ｗｂ为０．８１±０．０３。Ｗｂ（ｔ）和放射化学纯     

心肌显像剂^68Ga（BAT—TECH）的一些基本常数测定

研究了心肌显像剂＾６８Ｇａ（ＢＡＴ－ＴＥＣＨ）的动力学性质，测定了它的热力学常数。实验结果表明，ＢＡＴ－ＴＥＣＨ与柠檬酸镓的配体交换反应为二级反应，反应速率常数ｋ为０．５０ｌ／ｍｏｌ．ｓ，反应活化能Ｅａ＝５６．６ｋＪ／ｍｏｌ；＾６７Ｇａ（ＢＡＴ－ＴＥＣＨ）的稳定常数Ｉｇβ＝１４。９，配体ＢＡＴ－ＴＥＣＨ的四级氢解离常数ｐＫ１＝４．６２，ｐＫ２＝７．６８，ｐＫ３＝８．６８，ｐＫ４＝１１．２。     

^13N—NH3.H2O的制备与质量控制

利用＾１６Ｏ（ｐ，α）＾１３Ｎ核反应，以小体积＾１６Ｏ－Ｈ２Ｏ靶生产＾１３Ｎ正电子核素，即用１６．５ＭｅＶ的质子束轰击＾１６Ｏ－Ｈ２Ｏ靶５－２０ｍｉｎ后，以戴氏合金（Ｄｅｖａｒｄ．ｓＡｌｌｏｙ）还原靶水，可得么１．９－６．７ＧＢｑ的＾１３Ｎ－ＮＨ３．Ｈ２Ｏ。产品经ＨＰＬＣ分析，放化纯度〉９５％，载体ＮＨ３的浓度〈１ｍｍｏｌ／Ｌ，比活度为４．４ＰＢｑ／ｍｏｌ，适用于临床ＰＥＴ的研究。     

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.     

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.     

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.