神经受体显像剂放射性碘IBZM前体合成及碘标记

合成了苯酰胺类多巴胺Ｄ２受体显像剂＊Ｉ－ＩＢＺＭ的前体ＢＺＭ及非放射性ＩＢＺＭ，用氯胺－Ｔ法标记及用ＴＬＣ同时将游碘，反应前体ＢＺＭ与产品＾Ｉ－ＩＢＺＭ分离，产品放化纯度〉９０％。     

^3H—阿霉素及脑胶质瘤单抗的标记研究

用紫外光激活氚原子法对阿霉素标记，所得的＾３Ｈ－阿霉素仍具有生物活性，其比活度为９０ＴＢｑ／ｍｏｌ，然后用抗人脑胶质瘤单抗（ＭＡｂ ＳＺ－３９）通过多醛葡聚糖（ＰＡＤ）与＾３Ｈ－阿霉素桥联成＾３Ｈ－阿霉素－脑胶质瘤单抗免疫交联物，经凝胶柱纯化分离得纯品，其紫外吸收光谱与阿霉素单抗标准品的紫外吸收光谱相一致。动物实验证明，＾３Ｈ－阿霉素－脑胶质瘤单抗交联物在荷人脑胶质瘤裸小鼠瘤内高度浓集。     

多巴胺D2受体显像剂^125I—IBZM的合成与标记

合成了标记前体Ｓ－（－）－２－羟基－６－甲氧基－Ｎ－［（１－乙基－２－吡咯烷基）甲基］苯甲酰胺（Ｓ－（－）－ＢＺＭ）。光谱数据与结构相符。以Ｓ－（－）－ＢＺＭ为前体，用１２５Ｉ－ＮａＩ标记，成功地制备了Ｓ－（－）－３－１２５Ｉ－２－羟基－６－甲氧基－Ｎ－［（１－乙基－２－吡咯烷基）甲基］苯甲酰胺（Ｓ－１２５Ｉ－ＩＢＺＭ）。标记率大于８０％，放射化学纯度大于９０％，整个制备过程仅需４５ｍｉｎ，利于药盒化生产。     

MCNP－3B交互绘图功能的开发及改进

本文简要说明了对ＭＣＮＰ－３Ｂ绘图功能所进行的开发及改进的有关内容。介绍了其几何可视化、计算结果图的功能，叙述了用户界面、运行进程跟踪显示、曲面调配拼接等改进内容，说明了ＭＣＮＰ－３８／ＰＣ的结构。     

MCNP—3B交互绘图功能的开发及改进

本文简要说明了对ＭＣＮＰ－３Ｂ绘图功能所进行的开发及改进的有关内容。介绍了其几何可视化、计算结果图的功能，叙述了用户界面、运行进程跟踪显示、曲面调配拼接等改进内容，说明了ＭＣＮＰ－３８／ＰＣ的结构。     

~3H－阿霉素及脑胶质瘤单抗的标记研究

用紫外光激活氚原子法对阿霉素标记，所得的３Ｈ一阿霉素仍具有生物活性，其比活度为９０ＴＢｑ／ｍｏｌ，然后用抗人脑胶质瘤单抗（ＭＡｂＳＺ－３９）通过多醛葡聚糖（ＰＡＤ）与３Ｈ一阿霉素桥联成３Ｈ一阿霉素一脑胶质瘤单抗免疫交联物，经凝胶柱（ＳｅｐｈａｄｅｘＧ－１００）纯化分离得纯品．其紫外吸收光谱与阿霉素单抗标准品的紫外吸收光谱相一致。动物实验证明，３Ｈ一阿霉素一脑胶质瘤单抗交联物在荷人脑胶质瘤棵小鼠瘤内高度浓集。     

新的脑灌注显像剂^99mTc—MRP20配体的合成与标记

报道了Ｎ－［２（１Ｈ吡咯基甲基）］Ｎ＇－（４－戊烯－３－酮－２）－１，２－乙二胺（ＭＲＰ２０）的光谱数据与结构相符；元素分析结果与理论值一致；ＭＲＰ２０在室温下用亚锡还原可与＾９９ＴｃＯ（Ⅲ）生成配合物，标记率和放化纯大于９０％。     

放射性示踪技术研究金,铂在新型大孔树脂HHY—10A上的离子交换行为

应用１９５ｍＰｔ、１９９Ａｕ放射性示踪剂研究了金、铂在一种新研制的大孔强碱性阴离子交换树脂上的离子交换行为。系统研究了吸附和洗脱的条件，包括吸附介质的成分和酸度、洗脱剂以及吸附和洗脱流速的影响等。应用此法从标准参考物质ＤＺΣ－１、ＤＺΣ－２中分离和浓集出Ａｕ、Ｐｔ，用ＩＣＰ－ＭＳ测定，分析结果与推荐值符合良好。     

^99mTc—MIBI评价缺血／再灌注心肌活力的实验研究

应用＾９９ｍＴＣ－ＭＩＢＩ对家兔缺血／再灌注心肌细胞及线粒体代谢和活力进行了评价，将家兔ＬＡＤ阻断２０ｍｉｎ，３ｈ再灌主，于灌注后２－５ｍｉｎ静脉注射＾９９ｍＴｃ－ＭＩＢＩ，结果缺血３ｈ组缺血心肌再灌注早期（１０ｍｉｎ）晚期（３ｈ）相对放射性活度，心肌ＡＴＰ含量均明显低于缺前２０ｍｉｎ组，非缺血心肌和缺血２０ｍｉｎ心肌＾９９ｍＴｃ－ＭＩＢＩ亚细胞分布与ＳＤＨ活性呈显著正相关（ｒ＝０．８８，Ｐ〈０．     

NJOY－WIMS程序系统的研制

ＮＪＯＹ－ＷＩＭＳ程序系统是在开发ＮＪＯＹ（包括ＷＩＭＳＲ）、ＷＩＭＳ等程序，增加有关管理模块ＳＣＮ和ＣＣＭＩＴ的基础上建立起来的。这个系统习以用来进行ＷＩＭＳ库的制作及临界安全计算。作者由微观ＪＥＦ－１出发，应用该系统给出了ＴＲＸ－１、２，ＢＡＰＬ－ＵＯ＿２－１、２、３的计算结果。经比较表明，该系统是可靠的。     

压水堆-回路管道的铸造工艺及其国产化

工艺评定表明,1 000 Mw压水堆核电厂(CPR1000)原选用的主管道铸件Z3CN20-09M(法国牌号)不锈钢的化学成分符合RCC-M采购技术规范,但力学性能并不能完全满足压水堆核岛机械设备设计和建造规范(RCC-M)的要求.本文从金属学角度分析了Z3CN20-09M不锈钢抗蚀性特点和力学性能强化机理,确立了主管道铸件冶炼化学成份的内控标准,使CPR1000核电厂核岛主管道铸件(以下简称主管道铸件)的工艺评定在保持抗蚀性和可焊性特点前提下,各项力学性能指标均满足RCC-M标准,且有较大的裕度,离散度小,质量稳定,综合性能达到领先水平.     

显微硬度法分析核电站主管道热老化趋势

使用显微维氏硬度计和冲击试验机研究了核电站主管道材料Z3CN20.09M在400 ℃加速热老化10 000 h前后的力学性能变化。结果表明,热老化导致试验材料的冲击吸收能下降;构成试验材料的铁素体相的显微维氏硬度上升,奥氏体相的显微维氏硬度基本保持不变。通过研究材料组织特征,剖析显微硬度与冲击韧性的关系,探索将显微硬度测试方法作为核电站主管道材料热老化趋势预测方法的可能性。     

Z3CN20.09M奥氏体不锈钢热老化冲击性能试验研究

采用GB/T19748-2005钢材夏比V型缺口摆锤冲击试验仪器化试验方法,对压水堆核电厂用离心铸造Z3CN20.09M奥氏体不锈钢主管道样品进行了实验室热老化的冲击性能研究。冲击试验数据的统计分析表明,热老化对Fiu/Fm比值不产生影响,而对冲击载荷有显著影响,对冲击能量的影响则更为显著。透射电子显微分析表明,热老化导致铁素体中出现沉淀物,并引发了奥氏体中位错组态的改变。与热老化时间lg t之间也满足线性关系。     

核电厂主管道材料低周疲劳寿命预测方法评价

采用总应变控制方法,对压水堆核电厂主管道国产材料Z3CN20.09M进行了室温与350℃温度下的低周疲劳试验研究,获得了材料的疲劳寿命演化规律。采用Manson-Coffin方程、单拉估算模型、拉伸滞后能寿命模型和三参数幂函数公式对该材料的低周疲劳数据进行了拟合。通过寿命预测结果比较发现,除单拉估算模型外,其他几种模型对350℃高温下疲劳寿命的预测结果分散性明显高于室温疲劳。在众多模型之中,单拉估算模型拟合效果较差且预测寿命偏于非保守,而室温下拉伸滞后能法预测精度相对较高,350℃下则采用三参数幂函数法获得的预测效果更好。     

Positive use of damping devices for piping systems — Some experiences and new proposals

An increase of the damping ratio is known to be very effective for the seismic design of a piping system. It is reported that the energy dissipation in piping supports contributes to increase the damping ratio of the piping system. In this paper, with regard to increasing the damping and reducing the seismic response of the piping system, three application methods of damping devices used in other engineering fields are reviewed: (1) direct damper, (2) dynamic vibration absorber, and (3) connecting damper. Based on the results of this review, the following three types of damping devices for piping systems are introduced: (1) visco-elastic dampler (direct damper), (2) elasto-plastic damper (direct damper), and (3) compact dynamic absorber (dynamic vibration absorber). The dynamic characteristics of these damping devices are investigated by a component test and the applicability of them to the piping system was confirmed by the vibration test using a three-dimensional piping model. These damping devices are more effective than mechanical snubbers to suppress the vibration of the piping system.     

An implicit three-dimensional finite-element formulation for long-duration structural analysis of piping systems

This paper describes an implicit three-dimensional finite-element formulation for the structural analysis of reactor piping systems. The numerical algorithm considers hoop, flexural, axial, and torsion modes of the piping structures. It is unconditionally stable and can be used for calculation of piping response under static or long duration dynamic loads.The method uses a predictor-corrector, successive iterative scheme which satisfies the equilibrium equations. A set of stiffness equations representing the discretized equations of motion are derived to predict the displacement increments. The calculated displacement increments are then used to correct the element nodal forces. The algorithm is fairly general, and is capable of treating large displacements and elastic-plastic materials with thermal and strain-rate effects.The implicit-time integration scheme described herein has been incorporated into the three-dimensional piping code SHAPS. Two sample problems are presented to illustrate the analysis. The first problem deals with a dynamic analysis of a pipe-elbow loop. The second problem studies the piping response to seismic excitation. The results are discussed in detail.     

Seismic stops vs. snubbers, a reliable alternative

The Seismic Stops methodology has been developed to provide a reliable alternative for providing seismic support to nuclear power plant piping. The concept is based on using rigid passive supports with large clearances. These gaps permit unrestrained thermal expansion while limiting excessive seismic displacements. This type of restraint has performed successfully in fossil fueled power plants.A simplified production analysis tool has been developed which evaluates the nonlinear piping response including the effect of the gapped supports. The methodology utilizes the response spectrum approach and has been incorporated into a piping analysis computer program RLCA-GAP.Full scale shake table tests of piping specimens were performed to provide test correlation with the developed methodology. Analyses using RLCA-GAP were in good agreement with test results. A sample piping system was evaluated using the Seismic Stops methodology to replace the existing snubbers with passive gapped supports. To provide further correlation data, the sample system was also evaluated using nonlinear time history analysis. The correlation comparisons showed RLCA-GAP to be a viable methodology and a reliable alternative for snubber optimization and elimination.     

Investigation of thermal aging damage mechanism of the Cast Duplex Stainless Steel

Besides the macro-mechanical properties for thermal aging effect published in “Thermal aging effect on Z3CN20.09M Cast Duplex Stainless Steel” (Nuclear Engineering and Design 239(2009) 2217-2223), the thermal aging damage mechanism is investigated in this paper through nano-indentation tests and micro-structures evolution examination. Numerical simulations were carried out with GTN continuum damage model to investigate the different crack propagation process for aging. The nano-indentation hardness values increase with aging time for both phases while the hardness values of the ferrite phase are much higher and increase much more. The nano-indentation energy indicating the toughness decreases for both phases with aging time. TEM results show that the Cr-enriched α′ phase precipitates in the ferrite phase which is considered as the critical reason making the dislocation slip difficult and causing the increase of the strength and reduction of the toughness. The crack initiates from the ferrite phase instead of the austenite phase from the SEM observation and FEA simulation results, which reflects the change of the fracture mechanism for thermal aging.     

Steam generator small bore piping socket weld inspection using the phased array ultrasonic technique

As nuclear power plants age, the likelihood of failures in the small bore piping used in those plants caused by exposure to mechanical vibrations during plant operations increases. While small bore piping failures rarely cause plant shutdown, the management of small piping has been a keen area of interest since their repair or maintenance requires a reactor trip. Steam generator (SG) drain pipe socket welds are small diameter piping connections (nominal pipe schedule 3–4 inches) susceptible to mechanical vibration. SG drain pipe socket weld failures have caused coolant leakage. Therefore, more reliable inspection technologies for small bore piping need to be developed to detect problems at an early stage and prevent pipe failures. This research aims to improve the reliability and accuracy of small bore piping inspections through the design, manufacture and application of a new phased array ultrasonic testing technique and inspection system for SG drain line socket welds.     

J integral estimation fracture analysis for circumferentially cracked carbon steel piping

The three-segment fitting method is presented to describe the material stress-strain curves with yield plateaus. A J integral estimation approach for carbon steel piping with circumferential through-wall cracks was developed. Failure assessment curves obtained using three options in the CEGB R6 approach were proposed for GB20 carbon steel piping under bending. The initiation and maximum moments predicted by the J estimation approach presented in this paper are quite close to the experimental values.