氯化银固体径迹探测器的试制

二十年来国外一些实验室对用掺杂氯化银单晶片记录带电粒子进行了一系列的研究。它的基本特性如下。 1.可记录带电粒子:其灵敏度与所掺杂质的种类和数量有关。对质子灵敏阈约为30MeV。 2.潜影衰退及稳定:受带电粒子照射后在粒子的路径上形成潜影,如不及时稳住,潜影会在几分钟到几小时之内自行消失。如在粒子照射的同时或粒子照射后立即用黄光照射晶片,就能把潜影稳住,甚至经半年以上也不致衰退。此即氯化银探测器的“开关”特性,是现有固体径迹探测器中唯一能开关的。     

核4型原子核乳胶在不充分显影和低温下灵敏度的研究

本文给出了核4型原子核乳胶在不充分显影条件下的灵敏度曲线,以及77 K低温下的灵敏“比电离”阈值。根据实验结果讨论了带电粒子形成的潜影分布与反差分辨显影的关系。     

基于Galerkin Nodal方法的升潜条件对并联通道流动不稳定性影响分析研究

针对矩形并联通道,基于Galerkin Nodal法建立了升潜条件下并联通道流动不稳定性分析集总参数模型,包括静止条件下并联通道流动不稳定性模型和升潜条件附加力模型,并基于此模型分析了升潜条件下并联通道流动不稳定性的影响。分析结果表明:升潜幅值对并联通道流动不稳定性影响不明显。当升潜加速度频率与系统脉动频率差别较大时,升潜加速度频率对界限功率影响不大;当升潜加速度频率与系统脉动频率相近时,会显著降低系统界限功率;当系统处于非对称工况时,升潜条件的影响将显著增强。     

深海潜器用小型核动力的研制与发展前景

介绍了国外深海潜器用小型核动力装置的现状与发展以及日本的深海研究潜器用小型核动力装置（ＣＲＸ）。阐述了我国研究开发潜器用小型核动力装置的重要性和必要性。论证了我国发展深海潜器用小型核动力装置的发展前景。     

电子束辐照PET薄膜制备有序多孔阵列高分子模板

本文用掩膜工艺电子束蚀刻技术产生具有潜影的聚酯(PET)薄膜,经强氧化液(浓硫酸与重铬酸钾的混合液)腐蚀,产生有序微米多孔阵列PET模板.讨论了辐照剂量、腐蚀时间以及腐蚀温度等因素对基膜蚀刻和腐蚀的影响.结果表明:随着辐照剂量、腐蚀温度和腐蚀时间的增加,PET基膜更易被腐蚀.IR、DSC测量结果表明:辐照导致化学键的断裂、非晶化转变,是导致辐照PET薄膜的腐蚀失重率增加的原因.用此方法制备了孔径大小一致的微米级有序多孔阵列PET模板.     

辐射损伤潜径迹的纳米尺度观测研究

综述了近年来用扫描隧道显微镜 (STM )和扫描力显微镜 (SFM)在原子水平上观测辐射损伤潜径迹的研究及进展。详述了辐射损伤潜径迹的形貌、损伤范围、损伤数密度、损伤几率等 ,对损伤潜径迹直径与能损的关系、损伤过程及各种可能的损伤机制进行了分析和讨论。     

电子能损引起的潜径迹

潜径迹是电子能损在凝聚态物质中引起重要效应之一,给出了一个关于引起潜径迹电子能损阈值,损伤截面以及径迹形貌的综合评述。     

HLCC法定量评价CBCT图像伪影

为解决CBCT图像评价标准不一问题,本文提出了一种基于HLCC的CBCT图像伪影定量评价方法。该方法通过CUDA模拟CBCT投影,然后用重排算法转换射束获得HLCC曲线,建立三个评价伪影严重程度的定量指标。实验结果表明:定量指标数值越小,表明图像伪影程度越轻,且带伪影的HLCC曲线的三个评价指标数值是不带伪影数值的4~846倍。图像伪影的主次关系可总结为:散射伪影射束硬化伪影几何伪影余晖伪影无伪影。该方法可在投影阶段客观判断图像伪影的严重程度,简单快捷。     

庐枞火山盆地铀矿地质特征及成矿控制因素

安徽庐枞火山盆地位于长江中下游成矿带中段,燕山期强烈的构造-岩浆活动孕育了盆地内铀成矿作用。在整理前人勘查及研究成果基础上,对铀矿地质特征进行了分析,总结了成矿控制因素。庐枞火山盆地铀矿与潜火山岩具密切时空和成因关联,铀成矿受潜火山岩、构造及地层岩性综合控制,但潜火山岩浆侵入作用是成矿关键因素。后续铀矿找矿工作,在对潜火山岩体外围有利空间勘查的同时,尤其要加强寻找与隐伏岩体有关的隐伏矿体,以实现铀资源扩大的预期。     

心肌灌注显像常见伪影的辨析

为探讨心肌灌注显像常见伪影的特征，提高诊断的准确性，对132例心肌断层影像进行了回顾分析，并以冠脉造影结果为标准判断伪影的有关。在充分识别各种伪影的情况下采用盲法重新诊断，并与既往诊断结果进行了比较，结果显示，衰减伪影和位移为影多见于^201Tl显像者。其中胸壁衰减伪影女性多见，表现为位置固定的左室前壁或侧壁缺损；膈肌衰减伪影常见于男性，在垂直长轴上常表现为下壁由前向后逐渐变细。位移伪影常表现为室壁上的浓度与稀疏的同时存在，非靶器官放射性摄导致伪影，最多见于^99mTc-MIBI显像的病人，此时常在三个断面上同时发现有肝或肠道影，重新读片后，误诊率由原来的13．6％下降到6．8％，此结果表明，各种伪影均有其影像特征和出现的特定前提；多数伪影在实践过程中能为人们所认识，但仍有部分伪影难于识别，认真分析其特征有助于进一步提高诊断的准确性。     

快中子诱发~(238)U裂变中子能谱的核-4乳胶测量

介绍了用核-4乳胶测量2.5 MeV中子诱发~(238) U裂变瞬发中子谱的实验条件和布局以及核乳胶中反冲质子径迹的显微镜读取和处理,并采用蒙特卡罗程序SRIM和拟合方法导出了该类乳胶中反冲质子的能量-射程解析关系式,进而反推得到了核乳胶处的裂变中子相对能谱,并进行了修正,最后将实验结果与经典的Maxwell理论模型计算谱进行了比较。结果表明,二者在不确定度范围内符合较好,验证了核-4乳胶在测量裂变中子谱高能段的有效性。     

Kinetics of Dissolution of Magnetite in PDCA Based Formulations

Magnetite is one of the important corrosion products of pressurised heavy water reactors (PHWRs) where carbon steel is the dominant surface in the primary heat transport system. Designing of formulations capable of dissolving magnetite is important for effective decontamination of such surfaces. The rate of dissolution of synthetically prepared magnetite was studied in low concentrations of PDCA containing acidic formulations. The effect of addition of ascorbic acid, citric acid, Fe²⁺-PDCA complex on the rate was also studied. The effects of pH and the temperature on the dissolution rate were determined. The PDCA as a complexant has some positive factors like low protonation constant and enhanced stability to radiation.     

Catalytic protection of stannous ion by ascorbic acid in diphosphonic acids solutions

The protective ability of ascorbic acid(Vc) on stannous ion and the influence of light irradiation on the stability of stannous ion in diphosphonate medium at pH=5 have been examined in order to attain minimal loss of stannous ion during the production of lyophilized radiopharmaceutical kits.The sum of stanous ion and Vc was determined with iodometric method.It was shown that the protective ability of Vc was still strong at Vc concentration much lower than that of stannous ion and the illumination by fluorescent lamp was unfavorable to the stability of stannous ion.The change of pH in the range 3-9 did not affect the action of Vc significantly.     

流加对前体物发酵法合成15NL色氨酸的影响

以经过诱变和5-甲基色氨酸处理的假丝酵母突变株AS60为出发菌株，研究了在前体物发酵合成15NL-色氨酸过程中，分别流加葡萄糖、15N硫酸铵及15N邻氨基苯甲酸对发酵的影响。结果表明：在发酵36h后，分别流加1.5 g/L 的15N邻氨基的苯甲酸、2.1 g/L的15N硫酸铵以及50 g/L葡萄糖时，可使发酵液中15NL-色氨酸的产量达到3.073g/L。     

多巴胺D2受体显像剂99Tcm-m-Br-p-EBZM的合成

以与多巴胺有较高亲和力的2-溴-4-(1-乙基-吡咯烷基-2-甲基)-氨甲酰基-5-甲氧基-苯胺为母体进行结构改造,再与L,L-乙撑基胱氨酸二聚物(L,L-ethylenecysteine dimer,ECD)分子偶联合成了标记前体m-Br-p-EBZM,再通过两步法进行99Tcm标记,制备99Tcm-m-Br-p-EBZM,并对其进行了稳定性的考察.结果成功制备了99Tcm-m-Br-p-EBZM,放化纯度＞98%,且有较好的稳定性和较高的脂溶性.表明99Tcm-m-Br-p-EBZM可能成为理想的多巴胺受体显像剂.     

γ射线引发甲基丙烯酸十二酯乳液聚合及其吸油性能的研究

讨论了以OP-10、十二烷基苯磺酸钠为乳化剂，γ射线引发甲基丙烯酸十二酯与少量N-羟甲基丙烯酰胺和丙烯酸乳液聚合制备高吸油性树脂。分别采用红外，SEM和TG表征了聚合物的成分、结构和热性能。SEM显示乳液胶束粒子尺寸均一，粒径约为170nm。聚合物在300℃以下时热稳定性良好。研究了反应条件如吸收剂量、剂量率、固含量、N-羟甲基丙烯酰胺和丙烯酸用量等对聚合物的吸煤油性能的影响。聚合物对煤油、氯仿、二甲苯的最大饱和吸油率（g儋）分别为18．1、19．5和15．3。     

Preparation and characteristics of ^117mSN—HEDTMP

Tin-117m(t1/2 14d;γ159keV,86%) is an ideal tracer for studying biological behavior of tin compounds as well as for developing clinically-useful radio-pharmaceuticals.It had been reported that Sn-117m[4 ] DTPA has unexpectedly high bone uptake and bone-to-blood ratio,and is potentially useful as an agent for skeletal scintigraphy and radiotherapy of bone tumors.In this work.HEDTMP [N-(2-hydroxyethyl)ethlenediamine-1,1,2-tri(methylene phosphonic acid)] was synthesized.Let it form complex with ^117mSn.The formation conditions,stability and distribution coefficient between oil and water of the complex were investigated.     

Nanographene oxide labeling with 188Re

Nanographene oxide (NGO) is currently being explored for various biomedical applications. However, little information is known about its biological behaviors in vitro and in vivo. For further studying its pharmacokinetics and related biological behaviors in living systems, an effective and convenient tracing method is particularly demanded. In this work, NGO was labeled with radionuclide 188Re (188Re-NGO). To obtain high labeling yield and purity, a number of labeling conditions, including concentration of SnCl2 and ascorbic acid, reaction time and temperature, and pH were optimized, and stability of the 188Re-NGO in vitro and in vivo was evaluated. The results showed that NGO could be effectively labeled with high yield. The purified 188Re-NGO showed high stability in vitro and in vivo. A pretest of NGO biodistribution with single photon emission computed tomography showed that the 188Re-NGO was rapidly taken by organs such as lungs, liver, and spleen. The biodistribution of 188Re-NGO differs significantly from the free radionuclide, indicating that the labeling procedure is highly suitable for investigating its biological behavior in living systems.     

Dissolution of Haematite in Citric Acid-EDTA-Ascorbic Acid Mixtures

This study is related to the development of a suitable mixture of citric acid, EDTA and ascorbic acid (CEA) for dissolving the haematite deposited on the structural surfaces of cooling water circuits in BWRs. The dissolution experiments were performed with synthetically prepared haematite. The dependence of the dissolution rates on each of the constituents of the mixture has been evaluated using a ‘grain model’. It was found to be Langmuirianin the case of citric acid, linear in the case of EDTA and independent of ascorbic acid concentration. The ratio of molar concentration of the ligand to the total iron was varied from 0.5—2.5. Activation energy of the dissolution in a CEA mixture having stoichiometrically excess EDTA has been determined by performing experiments upto 353 K. The highest dissolution was obtained in 11:44:4 mol·m^?3 and 2:55:4 mol·m^?3 CEA mixtures.     

Preparation and bio-distribution of 153Sm-HEDTMP as a radiopharmaceutical for bone metastases

1 Introduction Metastases to skeleton from prostate, breast, andlung cancer are frequent in clinical practice. The pal-liation of patients with extreme pain of bone metasta-ses was of primary importance in clinical managementof patients with advanced cancer. Based on concentra-tion at sites of increased bone turnover, ra-dio-therapeutics was an effective alternative to con-ventional therapies. 153Sm-EDTMP (ethylene diaminetetramethylene phosphonate) has been developed topalliate su…