电位滴定法测定含肼硝酸溶液中的Pu（Ⅲ）和Pu（Ⅳ）

一、引言用超离心法测定锕系元素在硝酸介质中的扩散系数是有实际意义的研究课题。为了测定硝酸溶液中Pu(Ⅲ)的扩散系数,需制备Pu(Ⅲ)的硝酸溶液。肼还原法是常用的一种方法,肼既可作还原剂还可作Pu(Ⅲ)的价态稳定剂。由于在有大量钚的存在硝酸溶液中,时间放置长,肼会有一定的分解。Pu(Ⅲ)和Pu(Ⅳ)的相对含量也会发生相应的变化。为探索Pu(Ⅲ)与Pu(Ⅳ)浓度随时间变化的规律,必须定时测定它们的浓度。由     

心肌显像剂~（68）Ga（BAT－TECH）的一些基本常数测定

研究了心肌显像剂￣（６８）Ｇａ（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Ｅ＿ａ＝５６．６ｋＪ／ｍｏｌ；￣（６８）Ｇａ（ＢＡＴ－ＴＥＣＨ）的稳定常数ｌｇβ＝１４．９，配体ＢＡＴ－ＴＥＣＨ的四级氢解离常数ｐＫ＿１＝４．６２，ｐＫ＿２＝７．６８，ｐＫ＿３＝８．６８，ｐＫ＿４＝１１．２。     

反应堆退役废物中~3H，~（14）C，~（36）Cl，~（63）Ni和~（55）

用液闪计数法测定了国内某退役反应堆堆芯石墨中的~３Ｈ、~（１４）Ｃ、~（３６）Ｃ，及不锈钢、碳钢锈垢和水池底泥中~３Ｈ、~（６３）Ｎｉ、~（５５）Ｆｅ，并对上述固体介质样品的制样与测量问题进行了讨论。     

~（153）Sm、~（90）Y、~（166）Ho和~（186）Re放射性核素溶

用４πβ和４πβ－γ符合方法，对￣（１５３）Ｓｍ、￣（９０）Ｙ、￣（１６６）Ｈｏ和￣（１８６）Ｒｅ放射性核素溶液活度进行绝对测量，分别对这４种核素完成了标准化。前３种测量结果不确定度为０．７３％（１σ），对￣（１８６）Ｒｅ核素测量结果不确定度为０．６３％（１σ）。     

~（nat）W（p，xn）~（181─186）Re反应的激发函数

使用叠靶技术测量了２２．５ＭｅＶ的质子照射天然钨时生成~（１８１）Ｒｅ、~（１８２）Ｒｅ~ｍ、~（１８２）Ｒｅ~ｇ、~（１８３）Ｒｅ、~（１８４）Ｒｅ~ｍ、~（１８４）Ｒｅ~ｇ和~（１８６）Ｒｅ的激发函数。估算了~（１８６）Ｗ（ｐ，ｎ）~（１８６）Ｒｅ反应生产用于治疗的放射性核素~（１８６）Ｒｅ的厚靶产额，并与~（１８６）Ｗ（ｄ，２ｎ）~（１８６）Ｒｅ反应的有关数据进行了比较。     

~（99）Tc~m－HMPAO构效差异的研究──GSH水溶液中~（99）Tc￣

从化学动力学角度对ｄｌ－型和ｍｅｓｏ－型￣（９９）Ｔｃ￣ｍ－ＨＭＰＡＯ构效差异的原因进行了研究。通过测定￣（９９）Ｔｃ￣ｍ－ＨＭＰＡＯ两种异构体在ＧＳＨ和Ｌ－半胱氨酸水溶液中的解离反应的一级速率常数，比较了Ｌ－半胱氨酸和ＧＳＨ对￣（９９）Ｔｃ￣ｍ－ＨＭＰＡＯ作用，解释了ｄｌ－型和ｍｅｓｏ－型￣（９９）Ｔｃ￣ｍ－ＨＭＰＡＯ药效的差异，探讨了￣（９９）Ｔｃ￣ｍ－ｄｌ－ＨＭＰＡＯ在人脑中的贮留机理。     

~（85）Sr、~（134）Cs和~（60）Co在浅地层黄土与地下水间的分配系

本文报道了￣（８５）Ｓｒ、￣（１３４）Ｃｓ和￣（６０）Ｃｏ在采自本院野外试验场，从地表到地下２ｍ深黄土与地下水间分配系数的测定结果，以及核素浓度、ｐＨ和温度对分配系数的影响。黄土采集的深度范围分别为：地表－０．５ｍ，０．５－１ｍ，１－１．５ｍ，１．５－２ｍ，共采集１６个样品；地下水取自试验场的井水。实验采用静态法。实验结果表明，１６个样品测定的￣（８５）Ｓｒ、￣（１３４）Ｃｓ和￣（６０）Ｃｏ的分配系数的均值分别为８２、７．４×１０￣３和５．４×１０￣３ｍＬ／ｇ；在不同深度的黄土中测得的分配系数基本一致。ｐＨ值的变化对￣（１３４）Ｃｓ和￣（８５）Ｓｒ的分配系数有较大影响，对￣（６０）Ｃｏ则影响不大。     

EXAFS Studies of （Pb,Cd） 1212 phase superconductor and （Bi,Cd）1212 phase compound

We synthesized (Pb,Cd)Sr2(Y,Ca)Cu2O7 x,phase superconductor.After substitution of Pb with Bi,the BiCd1212 phase shows no superconductivity.Although previous EXAFS study has shown the local structure environment of the Cu is similar in both compounds,EXAFS results of Bi and Pb here demonstrate that σ2 of Pb-Oin-plane is larger than that of Bi-O inplane,whereas σ^2 of Pb-Oapical is smaller than that of Bi-O,wherase σ^2 of Pb-O apical is smaller than that of Bi-Oapical.The Sr shell features are also differnet,it appeared that superconductivity needs some disorder .in carrier reservoir layer,which is due to the substitutional defect caused by different ionic radii.     

将铀（Ⅵ）与锕系元素（Ⅳ）和／或锕系元素（Ⅵ）分离的方法及其应用

本发明涉及一种从选自除铀（VI）以外的锕系元素（IV）和锕系元素（VI）的一种或多种锕系元素分离铀（VI）的方法,其特征在于该方法包括以下步骤：a）使不与水混溶、含有所述铀和一种或多种所述锕系元素的有机相与含有至少一种缺位杂多阴离子的酸性水溶液接触,     

~（99m）Tc（V）－DMSA大鼠体内药代动力学

用改良方法成功制备了五价锝标记的二巯基丁二酸（９９ｍＴｃ（Ｖ）－ＤＭＳＡ）。根据血样时间－放射性曲线，该药在大鼠体内的代谢符合开放型二房室模型。主要动力学参数为Ｔ１／２（α）＝３．４ｍｉｎ，Ｔ１／２（β）＝７０．９ｍｉｎ，Ｖ（ｃ）＝２７２ｍｌ，Ｋ２１＝０．０５８ｍｉｌ－１，Ｋ１０＝０．０３４ｍｉｎ－１，Ｋ１２＝０．１２２ｍｉｎ－１。结果表明，９９ｍＴＣ（Ｖ）－ＤＭＳＡ从血液向组织的分布速度快，分布范围极广，体内消除迅速，基本从血中清除仅需６—７ｈ．为该显像剂的临床应用提供了实验基础。还研究了该药在大鼠血中的存在形式。     

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.