^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。     

乙酰二茂铁缩4—苯氨基硫脲与UO^2＋2,Hg^2＋,Ni^2＋,Zn^2＋,的…

乙酰二茂铁缩４－苯氨基硫脲（Ｃ１９Ｈ１９Ｎ３ＳＦｅ）与某些金属离子在无水乙醇中反应得到了希夫碱配合物Ｍ．Ｌ．Ｘ２．ｎＨ２Ｏ（Ｍ为ＵＯ＾２＋２，Ｈｇ＾２＋，Ｎｉ＾２＋，Ｚｎ＾２＋，Ｌ为Ｃ１９Ｈ１９Ｎ３ＳＦｅ；ＮＯ＾－３，Ｃｌ＾－，１／２ＳＯ＾２－４；ｎ＝０－６）并对配合物的组成及某些物理化学质进行了测试和表征。     

中能重离子与^natW相互作用中Hf的同位素分布

用放射化学方法测量了４０ＭｅＶ／ｕ＾４０Ａｒ，１０＼６５ＭｅＶ／ｕ＾８４Ｋｒ，８０ＭｅＶ／ｕ＾１６Ｏ，１３５ＭｅＶ／ｕ＾１２Ｃ＋＾ｎａｔＷ反应中Ｈｆ的生成截面，得到了Ｈｆ的同位素分布。研究表明，利用ＨＩＲＦＬ能量的重离子和丰中子重靶作用，能以一定的截面生成Ａ＞１７０区丰中子新核素，Ｎ／Ｚ值高的炮弹有利于丰中子核素的生成，过高的炮弹能量对丰中子新核素的生成没有贡献。     

高能γ射线参考辐射场空气比释动能（率）测定

本文主要介绍了用两种不同体积的石墨空腔电离室对静电加速器上通过＾１９Ｆ（Ｐ，ａ，ｒ）＾１６Ｏ反应产生的６－７ＭｅＶｒ射线参考辐射和在游泳池反应堆上通过Ｎｉ的中子俘获反应产生的７－９ＭｅＶｒ射线参考辐射的空气比释动能Ｋａ的测量方法的结果。     

联合在束γ装置的发展和实验

简要介绍了联合在束γ装置,经过十多年实验和发展的基本概况,以及最近使用１０套ＢＧＯ（ＡＣ）ＨＰＧｅ探测器在北京ＨＩ－１３串列加速器上进行了＾１２８Ｔｅ＋＾１９Ｆ、＾ＮＺｒ＋＾１９Ｆ、＾１１５Ｉｎ＋＾３５Ｃｌ反应的首批实验。     

CCl4萃取分离碘时放射性碘与载体碘的同位素交换

研究了用ＣＣｌ４萃取法分离４７ＭｅＶ／ｕ的＾１２Ｃ离子与＾１３３Ｃｓ反应产生的碘时，放射性碘与不同价态的载体碘之间的同位素交换。结果表明：在碱性介质中用ＮａＣｌＯ把载体Ｉ＾－氧化为ＩＯ＾－４，再在酸性溶液中用ＮＨ２ＯＨ·ＨＣｌ还原到Ｉ２，然后用ＣＣｌ４萃取分离出碘，放射性碘与载体碘之间的交换是完全的。     

核纯U3Si2粉末中铀的测定

试样用ＨＮＯ３－ＨＦ分解，加入Ｈ２ＳＯ４后加热至Ｈ２ＳＯ４冒烟以除去Ｓｉ，ＨＮＯ３和ＨＦ。在含有氨基磺酸的浓磷酸溶液中，用过量ＦｅＳＯ４将铀（Ⅳ）。剩余的Ｆｅ＾２＾＋以钼（Ⅳ）作催化剂，用ＨＮＯ３氧化。加入ＶＳＯ４溶液后，用标准Ｋ２Ｃｒ２Ｏ７溶液滴定铀（Ⅳ）至铀（Ⅵ），以电位法确定滴定终点。方法的精密度优于±０．１％，误差≤±∩．１％。     

50MeV/u12C6+离子辐照B16细胞氧效应研究

实验以体外培养的小鼠Ｂ１６黑色素瘤细胞为材料,在５０ＭｅＶ／ｕ ＾１２Ｃ＾６＋离子的展宽Ｂｒａｇｇ峰区辐照细胞,得到的结果是这种离子的ＯＥＲ值为１．２５。说明这种能量的离子具有低的氧效应。     

中能^12C离子反应中^7Be的生成

在最高能量为４７ＭｅＶ／ｕ的＾１２Ｃ离子和Ｍｙｌａｒ、天然铜或＾９３Ｎｂ相互作用中，用离线γ能谱法测量了＾７Ｂｅ的放射性活度，观察到的＾７Ｂｅ起源于入射＾１２Ｃ炮弹的碎裂和靶碎裂两种过程。估计＾７Ｂｅ的产额为１．１×１０＾７Ｂｑ／μＡ·ｈ（单位中的μＡ是粒子μＡ），讨论了利用中能重离子反应生产＾７Ｂｅ以及其它放射性核素的可能性。     

85 MeV19F离子辐照InP正电子湮没研究

用正电子湮没寿命技术研究了注量为１．６＊１０＾１６ＣＭ＾－２Ｒ ８５ＭｅＶ＾１９Ｆ离子辐照ＩｎＰ产生的辐照效应。实验表明辐照在ＩｎＰ中产生单空位型缺陷。     

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.     

有效探测面积大于1000 cm2的正比计数器测量系统性能测试

为对自制的活性面积高达1 000 cm²的大面积源进行表面发射率定值,同时作为现有2πα、2πβ表面发射率标准装置能力的扩充,研制了一套内置式大面积2π多丝正比计数器测量系统,并利用活性区直径为8 mm的²⁴¹Am点源及活性区面积为10 cm×15 cm的大面积²⁴¹Am和⁹⁰Sr-⁹⁰Y源对其进行计量学性能测试。结果表明：计数器内计数响应均匀性优于±0.4%,有效探测面积达1 400 cm²;所得²⁴¹Am源高压坪曲线的坪长为1 400 V,坪斜为0.27%/100 V,坪区内计数变化为0.87%;⁹⁰Sr-⁹⁰Y源高压坪曲线的坪长为300 V,坪斜为0.75%/100 V,坪区内计数变化为0.80%;10次测量重复性好于0.4%,8 h内短期稳定性好于0.3%,1 a内长期稳定性好于0.8%。     

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.