打磨态690TT合金经不同时间浸泡后表面氧化膜结构分析

利用多种分析手段深入分析了打磨处理的690TT合金在模拟压水堆一回路高温高压水环境中经不同时间浸泡后表面生长的氧化膜的微观结构.结果表明,从短期氧化到长期氧化.氧化膜表面形貌变化不明显;氧化膜主要由尖晶石结构的氧化物和单质Ni构成.浸泡96和1440 h后,氧化膜主要由富含Cr的氧化物构成.浸泡720,1440和2160 h后,氧化膜均由外层、中间层和内层构成:外层是分散的富含Ni和Fe的尖晶石结构的大颗粒氧化物;中间层是致密的富含Cr的尖晶石结构的小颗粒氧化物;内层是均匀连续的富含Cr的氧化物.中间层和内层氧化物能对基体起到良好的保护作用;随着氧化时间的延长,保护层的平均生长速率逐渐降低.打磨处理促进了690TT合金表面保护性氧化膜的生长.     

水电站户外照明配电系统的保护接地

水电站枢纽布置区域较大．且有可靠的大面积电站接地网,其户外照明场所各有特点。阐述了照明配电系统4种保护接地方式,分析了各种保护接地方式的可靠性及适用性,在设计水电站户外照明时,应分析其场所特性,结合水电站进场道路、进厂交通隧道、生活区、户外开关站以及出线平台等户外照明场所的特点,提出水电站户外照明配电系统的保护接地方式。     

~3H_e和~4H_e及其混合气体输运性质的理论研究

本文应用TT势计算了~3He和~4He气温体在0.1K—3273K温度范围内的粘滞系数和热传导系数,以及~3He和~4He气体等摩尔二元混合在0.1—373K内的输运性质,计算结果与Kestin等人的数据符合得很好。计算中用了经典和量子力学两种输运截面公式,T=373K时两种计算得出的输运系数,其相对偏差在0.7％左右,随温度降低偏差逐渐增大。     

S频段统一测控雷达健康故障诊断系统的设计

针对S频段统一测控系统故障诊断及健康管理的需求,给出故障诊断软件体系架构,并基于故障树的设备故障诊断开展了LNA+D/C设备状态评估设计。健康故障诊断系统以可更换单元或模块的监测信息为基础,综合利用自动测试和标校结果,收集、存储、诊断全系统设备工作状态,并依据建立的系统健康诊断和任务能力预测模型,实现设备健康状态预测和任务能力评估功能,为资源调度提供决策依据。     

甲型副伤寒多糖-破伤风类毒素结合疫苗的制备及安全性和免疫原性

目的制备甲型副伤寒多糖-破伤风类毒素结合疫苗,并检测其安全性与免疫原性。方法副甲O-SP溶液加入CDAP活化,己二酰肼(ADH)衍化,在碳二亚胺(EDAC)作用下与破伤风类毒素(TT)偶联,反应物经柱层析纯化,制得多糖蛋白结合物,经质量检测后,进行安全性及免疫原性试验。结果所制备的结合物多糖蛋白比稳定在0.6~0.8之间,CL-4B检测Kd≤0.2时的回收率大于75%,高相对分子质量结合物含量不低于90%。免疫双扩散试验显示结合物与副甲家兔超免血清和TT抗血清均产生可见沉淀线。动物安全试验均合格。结合物免疫小鼠后,其血清副甲LPS抗体滴度显著增长,阳转率达到100%。结论用CDAP活化多糖制备的甲型副伤寒-破伤风类毒素结合疫苗质量稳定,安全可靠,且具有良好的免疫原性。     

抗破伤风类毒素单克隆抗体的研究

用精被类（TT）免疫的BALB／c小鼠牌细胞与小鼠骨髓癌SP2／O细胞融合，获得4株能分泌中和破伤风毒素的单克隆抗体细胞株．所分泌的单抗能识别不同的抗原表位。一种单抗在小鼠体内可中和0．1～0．4IU／ml破伤风毒素，2种、3种和4种单抗混和后分别可中和20、350和750IU／ml。     

A study on wear coefficients and mechanisms of steam generator tube materials

Reciprocating sliding wear tests were performed to evaluate wear properties of Inconel 600MA and 690TT steam generator (SG) tube materials against 405 and 409 ferritic stainless steels. With increasing normal loads and sliding amplitudes, the wear rate of tube materials increased but a wear transition occurred only in Inconel 690TT. Subsurface deformation strengthening seemed to be an important factor that determines the wear resistance of tube materials. After the wear test, the worn surfaces were observed to investigate the wear mechanism of tube materials using SEM. The results indicated that there are different mechanisms of wear particle removal between the tube materials. The differences are related to the degree of work hardening due to the differences in chromium content in the tube materials. Based on the present results, wear coefficient values for the life estimation of SG tubes were calculated according to the work-rate model at each test condition. The wear rate is lower for Inconel 690TT compared to that for Inconel 600MA. Finally, parameters that should be considered for evaluation of wear coefficients were discussed.     

Decision‐tree‐based methods for differential diagnosis of β‐thalassemia trait from iron deficiency anemia

Several discrimination indices have been proposed to distinct between β‐thalassemia trait (βTT) and iron deficiency anemia (IDA). This study is the first application of tree‐based methods for differential diagnosis of βTT from IDA. One hundred forty‐four patients with hypochromic microcytic anemia aged 18–40 years old from Ayat Hospital of Tehran were recruited. Classification and Regression tree, CHi‐squared Automatic Interaction Detector (CHAID), Exhaustive CHi‐squared Automatic Interaction Detector (E‐CHAID), Quick, Unbiased, Efficient Statistical Tree (QUEST), Classification Rule with Unbiased Interaction Selection and Estimation (CRUISE), and Generalized, Unbiased, Interaction Detection and Estimation (GUIDE) have been used to discriminate the diagnosis. Mean corpuscular volume (MCV) was found as the main predictor in discrimination. All the mentioned tree‐based methods showed acceptable sensitivity, specificity, accuracy, Youden's index, false positive and negative rate, positive and negative predictive values and AUC in differential diagnosis of βTT from IDA. However, Classification Rule with Unbiased Interaction Selection and Estimation revealed more precise classification with an area under the curve value of 0.99. Decision‐tree‐based methods can be used to develop sensitive and accurate diagnostic methods for differentiating βTT from IDA.     

Effects of dissolved oxygen on corrosion fatigue cracking of Alloy 690(TT) in pressurized water reactor environments

Alloy 690(TT) is widely used for steam generator tubes in pressurized water reactor (PWRs), where it is susceptible to corrosion fatigue. In this study, the effects of dissolved oxygen on the corrosion fatigue cracking behavior of Alloy 690(TT) in simulated PWR environments were investigated under small scale yielding conditions. Dissolved oxygen, combined with the monotonic plastic zone size (r_p), had a significant influence on out-of-plane cracking of corrosion fatigue crack and environment factor (F_en).