聚苯乙烯微球化学制备及镀镍工艺研究

在聚苯乙烯微球表面进行化学镀镍可以制备磁性微球.采用此方法,能将聚苯乙烯的轻质的优点和镍的磁性结合起来.同时,此方法还具有如下优点:操作简单、反应条件易于控制.采用扫描电镜(SEM)表征了微球的表面形貌.考察了施镀温度、镀液浓度、镀液pH值对结果的影响.     

变压吸附制氮技术的发展和应用

综述了变压吸附技术的原理、发展及碳分子筛和沸石分子筛两种吸附剂变压吸附技术制氮的国内外研究进展,提出了变压吸附技术制氮的发展方向。     

投影寻踪分类模型在常见造纸纤维原料综合评价中的应用

将投影寻踪分类（PPC）模型与基于实数编码的加速遗传算法（RAGA）相结合,同时优化多个指标参数,将高维数据指标转化为低维空间上的一维投影值,建立RAGA-PPC模型,用于造纸纤维原料分类,并对造纸纤维原料进行综合评价。结果表明,基于RAGA-PPC模型的评价结果与造纸纤维原料实际分类结果一致,此方法客观可靠,精度高,具有一定的应用前景。     

循环氢压缩机活塞杆磨损分析及改进

针对某石化公司柴油加氢装置循环氢压缩机活塞杆磨损拉伤的事件进行深入分析,从填料函以及活塞杆探头故障表现入手,找出其磨损的根本原因,通过对隔板填料的结构和材质进行优化改进,调整活塞杆探头的位移间隙等措施,彻底解决了压缩机活塞杆磨损的问题,确保设备的长周期稳定运行,装置的安全平稳生产.     

燃机余热锅炉排烟酸露点温度计算研究

整理分析天然气燃烧产生的烟气酸露点的影响因素,并通过多种方法计算某燃气—蒸汽联合循环机组余热锅炉排烟酸露点温度,总结出一套适用于燃机电厂余热锅炉排烟酸露点温度的可靠计算方法,以降低余热锅炉排烟温度、优化燃机电厂运行方式以及提高机组效率提供计算依据和参考.     

非破损方法检测高强混凝土的应用研究

阐述了高强混凝土的定义及国内、国外应用现状.提出建筑结构安全与非破损检测有着紧密的关系,并介绍了非破损检测在建筑工程质量评估中的应用范围.介绍了非破损检测的分类、优缺点,并通过实验说明了各种非破损检测方法的精度,最后给出了4种非破损检测方法的计算公式及强度曲线.     

1 GWt PB-FHR负荷跟踪运行特性分析

为研究熔盐堆系统在商业应用中的价值,分析其是否满足电网负荷的变化需求和安全运行的能力,本文以1 GWt球床式氟盐冷却高温堆（PB-FHR）为研究对象,仿真计算其在负荷跟踪模式下的瞬态行为和运行特性。以RELAP5/MOD4.0程序为研究工具,并植入相关的熔盐物性与计算关系式,建立氟盐冷却高温堆的热工水力系统与功率控制系统的仿真模型,对典型负荷工况参数变化情况下控制系统的响应特性进行仿真分析。结果表明：该氟盐冷却高温堆系统在设计的控制逻辑的调控下,展示出良好的负荷跟踪运行能力,堆芯功率能迅速响应负荷变化,功率超调和温度超调小,反应堆的运行参数始终处于合理的运行范围内。     

Study on element detection and its correction in iron ore concentrate based on a prompt gamma-neutron activation analysis system

A prompt gamma-neutron activation analysis(PGNAA) system was developed to detect the iron content of iron ore concentrate. Because of the self-absorption effect of gamma-rays and neutrons, and the interference of chlorine in the neutron field, the linear relationship between the iron analytical coefficient and total iron content was poor, increasing the error in the quantitative analysis. To solve this problem, gamma-ray self-absorption compensation and a neutron field correction algorithm were proposed, and the experimental results have been corrected using this algorithm. The results show that the linear relationship between the iron analytical coefficient and total iron content was considerably improved after the correction. The linear correlation coefficients reached 0.99 or more.     

Attenuation correction of polychromatic L-shell X-ray fluorescence computed tomography imaging

Polychromatic L-shell X-ray fluorescence computed tomography is a promising imaging technique to explore the element distribution of the sample. However, the image quality of large samples would be decreased dramatically due to the present of the self-absorption. In this investigation, an attenuation correction algorithm based on theories related to X-ray fluorescence was proposed. With this method, the attenuation coefficients at the incident energies were expressed as a function of known X-ray energies and unknown platinum concentrations. Then the attenuation coefficients were calculated based on the theories and added in the contribution value of the pixel in Maximum Likelihood Expectation Maximization reconstruction method. The element distributions can be got through continuous iterations. Finally, the feasibility of this method was tested by Monte Carlo simulation. The results indicated that, for a 4-mm diameter phantom containing an object of 2 mm in diameter with 0.10 wt% platinum solutions, the CNR of reconstructed images increased from 53.5 to 203.8 after attenuation correction while the relative error decreases from 97% to 2%.     

火花放电原子发射光谱仪分析高含量硅时校准曲线的扩展与应用

火花放电原子发射光谱仪分析高含量Si(w(Si)≥3.0%)时,其元素含量已超出了校准曲线的线性范围,导致分析值偏低。实验通过增加中低合金钢、硅钢标准样品,完善并扩展了Si校准曲线,完成了共存元素的干扰校正,拓宽了Si元素的分析范围,质量分数上限由3.14%扩展至4.16%,线性相关系数达0.99965。校准曲线扩展后重新选择标准化样品进行漂移校正,校准曲线强度比由9.41扩展至11.01。对扩展含量段的两个样品(w(Si)≥3.0%)进行精密度考察,结果的相对标准偏差(RSD,n=10)为0.43%和0.50%;对比了8个不同Si含量的样品,发现完善、扩展后校准曲线的Si测定值与认定值更相符;同时统计过程控制(SPC)控制图处于受控状态。可见校准曲线经完善、扩展后可满足工艺过程控制和成品分析要求。