5,5-二正十八烷基-2-(2-溴乙基)-1,3-二氧六环的合成及表征

研究了以 １－十八醇和丙二酸二乙酯为原料合成二五十八烷基丙二酸二乙酯，然后用 ＬｉＡｌＨ４还原得到 ２， ２－二正 十八烷基－１，３－丙二醇，再在对甲苯磺酸催化下与β－溴丙醛结合得５，５－二五十八烷基－２－（２－溴乙基）－１，３－二氧 六环。并对产物的重结晶条件进行了研究，产物经元素分析、ＩＲ和１ ＨＮＭＲ光谱表征。     

4-羟基-α，α，4-三甲基环己烷甲醇的合成

探讨了卤化锌催化香茅醛合成4-羟基-α，α，4-三甲基环己烷甲醇的工艺条件；确定了合成反应最佳的酸体积分数为2．71％，金属催化剂的用量为1．3629g，反应时间为18h．     

Comparison of 1-, 2-, and 3-Parameter IRT Models

This module discusses the 1-, 2-, and 3-parameter logistic item response theory models. Mathematical formulas are given for each model, and comparisons among the three models are made. Figures are included to illustrate the effects of changing the a, b, or c parameter, and a single data set is used to illustrate the effects of estimating parameter values (as opposed to the true parameter values) and to compare parameter estimates achieved though applying the different models. The estimation procedure itself is discussed briefly. Discussions of model assumptions, such as dimensionality and local independence, can be found in many of the annotated references (e.g., Hambleton, 1988).     

The new modes of Palladium - catalyzed cross - coupling, dimerization and domino - tetracyclization of boroxines, trans - 1 - Bromo - 2 - styrylbenzene, and bromodienynes. A personal Ph. D. And Postdoctoral research review

[I].Synthesisandpalladium -catalyzedcross -couplingreac tionoftris[4 - (trimethylsilyl)furan - 3-yl]boroxineandtris[4 -(substituted)furan - 3-yl]boroxine .3,4 -Disubstitutedfuransareimportantbuildingblocksofhet erocycliccompounds,inacontinuationofthestudyonpossibleroutesto 3,4 -disubstitutedfuran ,Iwasinterestedinexploringtheroleofasilylgroupasapotentialdirectinggroupbecausesilylgroupsarewell-knownfortheir ( -donatingcharacter.Theirtendencytostabilizea ( -carbocationthroughtheso -called (p - (…     

N,N,N,N-四丁基-B,B,B,B-四苯基-硼酸铵的合成与表征

N,N,N,N-四丁基-B,B,B,B-四苯基-硼酸铵是一种有机离子化合物,熔点224-226℃,在300℃以内能稳定存在。本文报导了它的合成,产率为97.2%。通过红外和X-射线测定,确认了产物的结构。本合成方法简便易行,适合大规模生产。预期该化合物在活泼金属电解和作为250-300℃范围内的反应溶剂将有很好的开发应用价值。     

Production of temporal terms by 3-, 4-, and 5-year-old children

This study investigated changes in the production of temporal terms over the preschool years. Ninety-three parents of 3-, 4- and 5-year-old children completed a questionnaire in which they indicated their child's production, and accurate use, of a list of temporal words. The results suggest that use and command emerge at different ages for different terms. Correlation and difference analyses were conducted to document the pattern of development. Words representing the present (e.g., now) and very general temporal terms (e.g., ‘later’) were produced and used accurately by the majority of even the youngest children. Some terms describing specific timeframes (e.g., ‘yesterday’) were also produced from a young age but demonstrated more gradual acquisition of appropriate use across the preschool years. Other terms appeared in children's vocabularies only later in the preschool years, and were inaccurately used even by the oldest children (e.g., ‘hours’). These findings provide an initial survey of reported child competence with temporal words that has implications for research, education, and judicial contexts.     

生命力·生长点·生命载体 --对马克思主义的几点思考

要不断增强马克思主义的吸引力、凝聚力,进一步巩固马克思主义的指导地位,就必须永葆马克思主义的生命力,寻找和培育马克思主义的新生长点,进一步坚实马克思主义的生命载体.     

5,6,7,8-四氢-2-萘酚的合成研究

以2-萘酚为原料，用RaneyNi做催化剂，在较小的压力下反应合成5，6，7，8-四氢-2-萘酚，收率稳定，在68％以上。     

Cl2-,O2-和N2-的势能函数研究

本文采用从头计算的方法对Cl2-,N2-和O2-的势能函数进行了数值计算,采用最小二乘法拟合出了Murrell-Sorbie势能函数的参数,并根据拟舍出的参数值求出力常数和光谱数据.     

N-(4-氯苯基)-N''-(1,2,4-三氮唑)脲的合成

以4-氯苯甲酸为原料，经过CURTIUS重排反应制得4-氯苯异氰酸酯，再进一步与3-氨基-1H-1，2，4-三氮唑发生亲核加成反应，合成了目标化合物N-(4-氯苯基）-N'-(1，2，4-三氮唑）脲，其产率为89%。对目标化合物经元素分析、IR和^1HNMR表征，并初步测定了此化合物的植物生长调节活性。     

Research and Inspection: Hmi and OFSTED, 1981-1996 - a commentary

This paper traces the changing relationship between research and inspection under both HMI and OFSTED, from the early 1980s to 1996. Drawing on a mix of internal and external sources it describes the changes within HMI to make traditional inspection methods more transparent and consistent and to make more use of quantitative data and performance indicators in the 1980s. However, changes within HMI were overtaken by events as education moved rapidly up the political agenda from the mid-1980s. With the demise of HMI in 1992, research within OFSTED took on a more prominent role and a modest but innovative research programme was established. However, the shift by OFSTED in the mid-1990s to take on a more explicit campaigning role to raise educational standards, rather than simply be a regulatory organisation, put the research under pressure to fit in with this new style. The paper draws on examples of the way these pressures worked out in both externally commissioned and internal research exercises. The result was that some studies were sidelined, while others were given excessive prominence that could not be justified by the scale and nature of the research.