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1.
对丁腈橡胶-40(NBR-40)与三元共聚型氯醚橡胶(CHC)进行了并用研究.发现二者之间的相容性良好。NBR-40/CHC并用比为80/20时,胶料的综合物理性能较好;为70/30时.胶料耐40#机油的性能最好;耐四氯化碳溶剂的性能随并用比的减小(CHC用量增加)而提高。胶料硫化体系以过氧化物硫化体系[过氧化二异丙苯(DCP)/硫黄/四氧化三铅/促进剂NA-22]最佳,补强剂选用中超耐磨炭黑。  相似文献   
2.
This study employed structural equation modeling to examine the effects of Cattell-Horn-Carroll (CHC) abilities on reading decoding skills using five age-differentiated subsamples from the standardization sample of the Woodcock-Johnson III (Woodcock, McGrew, & Mather, 2001). Using the Spearman Model including only g, strong direct effects of g on reading decoding skills were demonstrated at all ages. Using the Two-Stratum Model including g and broad abilities, direct effects of the broad abilities Long-Term Storage and Retrieval, Processing Speed, Crystallized Intelligence, Short-Term Memory, and Auditory Processing on reading decoding skills were demonstrated at select ages. Using the Three-Stratum Model including g, broad abilities, and narrow abilities, direct effects of the broad ability Processing Speed and the narrow abilities Associative Memory, Listening Ability, General Information, Memory Span, and Phonetic Coding were demonstrated at select ages. Across both the Two-Stratum Model and the Three-Stratum Model at all ages, g had very large but indirect effects. The findings suggest that school psychologists should interpret measures of some specific cognitive abilities when conducting psychoeducational assessments designed to explain reading decoding skills. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
3.
Reduced low-density lipoprotein (LDL) cholesterol level is a characteristic feature of dyslipidemia in chronic hepatitis C virus (HCV) infection. However, abnormality in serum triglyceride (TG) has not been fully investigated. To clarify the impact of HCV genotype 1b (G1b) infection and advanced fibrosis on serum TG profiles, TG concentrations in lipoprotein fractions were examined in fasting sera from 185 subjects with active or cleared HCV infection by high-performance liquid chromatography. Serum lipoproteins were fractionated into four classes: chylomicron, very low-density lipoprotein (VLDL), LDL, and high-density lipoprotein (HDL). Then, the significance of HCV G1b infection on TG levels in each lipoprotein fraction was determined using multiple regression models. We found that active HCV G1b infection was positively associated with high HDL-TG levels and low VLDL-TG levels, independent of other factors included in the regression model. In VLDL sub-fractions, active HCV infection was only found to be associated with low levels of large VLDL-TG. Similarly, advanced liver fibrosis in chronic HCV G1b infection was associated with high levels of LDL-TG, HDL-TG, and small VLDL-TG, independent of other clinical factors. These findings indicate that active HCV G1b infection and advanced fibrosis are closely associated with abnormal serum TG profiles.  相似文献   
4.
田霖 《弹性体》2006,16(3):73-78
论述了我国氯磺化聚乙烯橡胶(CSM)、氯醇橡胶(CHC)、氯化聚乙橡橡胶(CPE)、丙烯酸酯橡胶(ACM)4种特种橡胶的现状及其最新进展,并对这几种特种橡胶的发展提出建议。  相似文献   
5.
基于结构部分结点振动响应信息的海洋平台损伤诊断研究   总被引:1,自引:0,他引:1  
利用结构的前三阶频率和部分结点的响应信息构建适应度函数和目标函数,采用改进的CHC遗传算法对结构进行损伤诊断,在相同的收敛精度条件下,大大减少了遗传代数和结构分析时间,因而提高了计算速度。数值算例表明:在不同的传感器配置条件下,对固定式导管架平台的损伤诊断均具有较高的损伤定位和损伤程度估计精度。  相似文献   
6.
一种基于CHC算法的自动组卷方法*   总被引:1,自引:0,他引:1  
利用改进的遗传算法——跨世代异物种重组大变异(cross generation heterogeneous recombination cataclysmic mutation,CHC)算法提出了一种自动组卷方法。初始种群即初始试卷集利用具有启发式信息的搜索算法产生;适应度函数是用户指定的试卷总体指标与试卷实际指标绝对误差的加权和;选择操作群体为当前群体与上世代群体的群体总和,因为大个体群操作可以更好地保持遗传多样性;交叉操作采用单点交叉方法。变异操作的步骤是:从上世代个体中挑选适应度较差的个体,对其中的  相似文献   
7.
This work analyzes the relative advantages of different metaheuristic approaches to the well-known natural language processing problem of part-of-speech tagging. This consists of assigning to each word of a text its disambiguated part-of-speech according to the context in which the word is used. We have applied a classic genetic algorithm (GA), a CHC algorithm, and a simulated annealing (SA). Different ways of encoding the solutions to the problem (integer and binary) have been studied, as well as the impact of using parallelism for each of the considered methods. We have performed experiments on different linguistic corpora and compared the results obtained against other popular approaches plus a classic dynamic programming algorithm. Our results claim for the high performances achieved by the parallel algorithms compared to the sequential ones, and state the singular advantages for every technique. Our algorithms and some of its components can be used to represent a new set of state-of-the-art procedures for complex tagging scenarios.  相似文献   
8.
According to the most widely accepted Cattell–Horn–Carroll (CHC) model of intelligence measurement, each subtest score of the Wechsler Intelligence Scale for Adults (3rd ed.; WAIS–III) should reflect both 1st- and 2nd-order factors (i.e., 4 or 5 broad abilities and 1 general factor). To disentangle the contribution of each factor, we applied a Schmid–Leiman orthogonalization transformation (SLT) to the standardization data published in the French technical manual for the WAIS–III. Results showed that the general factor accounted for 63% of the common variance and that the specific contributions of the 1st-order factors were weak (4.7%–15.9%). We also addressed this issue by using confirmatory factor analysis. Results indicated that the bifactor model (with 1st-order group and general factors) better fit the data than did the traditional higher order structure. Models based on the CHC framework were also tested. Results indicated that a higher order CHC model showed a better fit than did the classical 4-factor model; however, the WAIS bifactor structure was the most adequate. We recommend that users do not discount the Full Scale IQ when interpreting the index scores of the WAIS–III because the general factor accounts for the bulk of the common variance in the French WAIS–III. The 4 index scores cannot be considered to reflect only broad ability because they include a strong contribution of the general factor. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
9.
纳米二氧化钛光催化薄膜的研制   总被引:1,自引:0,他引:1  
采用溶胶-凝胶法(Sol-gel)制备了二氧化钛光催化薄膜,利用原子力显微镜(AFM)对薄膜表面结构进行观测.薄膜中二氧化钛粒子以纳米级分布,薄膜均匀、连续无龟裂.分别测试了纳米二氧化钛薄膜和普通二氧化钛颗粒在紫外灯照射下对CHCl3的催化降解速率.实验分析结果表明具有表面效应,量子尺寸效应的纳米二氧化钛薄膜有着更高的光催化活性和降解速率.  相似文献   
10.
施周渊  赵守臣  汤玉生 《压电与声光》2004,26(5):414-417,427
述了深亚微米MOS技术中热载流子(HC)退化效应的机理。重点讨论了超大规模集成(VLSI)中两个可靠性问题沟道热载流子(CHC)退化与静电释放(ESD)之间的相互作用,特别是漏/源工艺上的均衡和潜在的损伤。最后又说明了热载流子的产生如何优化ESD保护性能。  相似文献   
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