3 resultados para alfa de Cronbach

em Chinese Academy of Sciences Institutional Repositories Grid Portal


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本论文主要研究了毛细管电泳电化学发光分离检测技术在药物及生物分析中的应用,包括以下五个方面的内容: 1. 利用毛细管电泳电化学发光连用技术分离检测临床药物丙吡胺,详细考察了影响分离和检测的各种因素,在优化的实验条件下,此方法的检测限达到2.5×10-8 mol L-1 (S/N = 3),优于已报导的各种检测方法。该方法简单快速、高效灵敏。采取一种简单易行的液液萃取预处理,可成功用于实际加标尿样的分析。2. 发展了手性毛细管电泳电化学发光连用技术,成功实现了实际加标血浆中外消旋丙吡胺药物的手性分离。该工作首次将毛细管电泳手性分离与电化学发光检测结合起来,有一定的创新意义。与传统手性分离模式不同的是,该“非传统”手性分离模式中的毛细管进样端和出口端的缓冲溶液在种类、组成、离子强度及pH值等参数上均存在差异,不仅达到了理想的分离效果,同时实现了高灵敏的检测。3. 研究了毛细管电泳电化学发光连用技术中出现的诱导峰的成因,考察了影响诱导峰峰强度和峰位置的各种因素,提出了一种合理的机理进行成因解释。诱导峰的出现不是由于化学络合作用,而是分离缓冲溶液和注入的样品中的某些组分在动态电泳过程中所发生的物理作用导致的。4. 合成了钌配合物的电化学发光探针,基于亲和素修饰电极和蛋白质的电化学发光标记和生物素化的双重标记,实现了蛋白质的定量检测。利用碳纳米管对蛋白质强的吸附作用以及在缩合试剂存在的条件下羧酸功能化的碳纳米管可与蛋白质共价键和的双重特点,使亲和素固定到玻碳电极上;经生物素化和电化学发光探针双重标记的蛋白质分子(BSA)通过亲和素-生物素特异性相互作用结合到电极表面,在TPA存在的条件下并施加合适的扫描电位,所得到的ECL强度与蛋白质浓度在一定范围内成线性关系,从而实现蛋白质的定量测定。此普适性的方法也可成功用于溶菌酶的定量检测。5. 基于适配子的“三明治”模式和DNA的电化学发光标记,发展了一种新型的电化学发光适配子传感器,结合金纳米放大效应和巧妙的自组装过程设计,实现了凝血酶的灵敏、经济实效的检测。首先,金纳米溶胶标记的捕获适配子1固定到ITO电极上,结合上目标分子凝血酶后,另一种标记有电化学发光探针的探针适配子2也与凝血酶产生强的特异性相互作用,从而结合到电极表面上。在给定的条件下,所得ECL信号与目标分子凝血酶浓度相关,进行ECL检测,所得到的信号-浓度曲线很好地满足“三明治”反应模式的特点,检测限约为10nM。特异性考察说明此电化学发光适配子传感器对于alfa-凝血酶有着极好的选择性,而对bata,gamma-凝血酶基本无响应。

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The research objectives were to investigate the psychological structure of employees' organizational commitments(OCs), and its antecedents, and to examine the relative effects of employees' OCs to their performances. In order to deeply uncover the nature of OCs, some standard methods, such as in-depth interview, focus-group, semi-open questionnaire, standard questionnaire etc., were employed. In data analysis, not only some common statistical methods, such as multivariate analysis of variance, cross-table analysis, factor analysis, but also some forefront ones, such as confirmatory factor analysis and path analysis of SEM, were used. The paper covers six chapters: 1) In the first chapter, Firstly some previous empirical studies, which examined structures, antecedents, correlates, and/or consequences of organizational commitment in China and Western countries, were summarized. This summary covers most of the respectable researchers' works of this field, such as H.S.Becker, B.Buchanan, L.W.Porter, G. Ritzer, H.M.Trice, J.A.Alutto, L.G.Hrebiniak, R.T.Mowday, J.P.Meyer, N.J.Allen, G.W.McGee, R.C.Ford, R.Eisenberger, etc. Then three theoretical hypothesis were put forward as following: ① In China, OCs should be multidimensional psychological structures, which means there should exist more than one type of OCs; ② There should be some different antecedents to different OCs; ③ Employees with different types of OC should perform differently in their works. Finally the theoretical and practical significance were discussed. 2) In the second chapter, great efforts were made to investigate the OC types. Firstly, in-depth interview with managers and employees, semi-open questionnaire, and some other methods were used in the pilot research to gather much qualitative material. Then OC questionnaire was designed to get quantitative data in about 20 enterprises, including state-owned, collective-owned, wholly foreign-funded, and joint-ventures. During revising of this questionnaire, there were about 5000 samples surveyed. after factor analysis, the data shows that there should be 5 types of OCs in China, which were respectively named as Affective Commitment, Normative commitment, Ideal Commitment, Economic Commitment, Choice Commitment. Thirdly, confirmatory factor analysis method was used to successfully confirm this 5-factor model. Finally, Cronbach a and test-retest correlate indicate that this questionnaire is reliable. Since factor analysis result has show its construct validity, a simple criterion-related validity research was conducted. 3) In order to investigate the correlation between different OC and employee performance and different antecedents of OC, 5 other questionnaires, such as Employee Satisfaction Questionnaire, Perceived Organizational Support Questionnaire, Social Exchange Questionnaire, Altruism Scale, and Leader Confidence Scale were revised in the third chapter. 4)In the fourth chapter, a lot of correlates, cross-table analysis were conducted to show the correlation between different OCs and 10 performances, which indicate employees with different OCs will show different performance in 10 variables, such as altruism, etc. 5) In the fifth chapter, correlate analysis, multivariate of analysis, and path analysis of SEM were used to investigate the antecedents of OC. A satisfactory model showing the correlation between OC and their antecedents was confirmed. 6) In the last chapter, all researches about OC, and its limitations were summarized.

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Questionnaire of Stressors, which was constructed earlier, and Resilience Factor Scale were applied on 252 Chinese University students and 207 American University students. Reliability and validity tests were applied on the data. Results are as following: 1. Cronbach α coefficient of both scales were tested and showed good results. Construction validity of them was also tested by applying Factor Analysis on the data. The results are good. 2. Stressors of University students consist of three factors, named Survival Anxiety, Social Anxiety, and Role Stress. Resilience Factors consist of Social Support and Self-Efficacy. They affected each other. Significant correlation was found among those five factors. 3. Significant differences were found between Chinese sample and American sample in the scores of most items of the two scales.