用猪血、羽毛制取混合氨基酸稀土配合物

用猪血和鸡毛为原料，分别采用硫酸酸解和盐酸酸解两种工艺，获得混合氨基酸．与混合轻稀土化合物反应制得混合氨基酸稀土配合物．测定了配合物的化学组成，完成了成品的氨基酸含量和Ｘ－射线衍射分析．     

一种新型重油掺水乳化剂的研制

本文研制出一种新型重油掺水乳化剂，其特点是原料易得、合成路线简单、乳化性能好。实验发现，采用稀土化合物作为合成反应的催化剂可大大缩短反应时间，重油掺水量为２０％时，乳化剂用量为 ０．１５％。乳化剂的主要性能超过国内同类产品。     

碘及稀土催渗涂料碳氮共渗的研究

本文论述了碘及稀土催渗涂料碳氮共渗的处理工艺;试验了碘及稀土在涂料碳氮共渗中的催渗作用;研究了催渗剂量、共渗温度和保温时间对共渗层深度的影响,并试验了加催渗剂后,试样的冲击韧性。试验结果表明,此工艺具有渗速快,硬度高,冲击韧性显著提高的特点。     

稀土出口政策制定中博弈论计算应用研究

相对而言,我国具有稀土出口优势。但是,由于稀土行业发展尚处于初期阶段,无论是产业政策,还是资源消耗都存在一定的问题导致我国稀土资源优势下降。文章首先对当前稀土出口存在的问题进行阐述,然后,基于博弈论理论探索稀土出口贸易政策的优化,最后,对中美、中日就稀土出口问题的博弈模型进行定量分析,从而探索有效的稀土出口政策优化途径。     

稀土固体超强酸SO4^2-／TiO2／La^3＋催化合成丙酸环己酯

研究了以稀土固体超强酸为催化剂,丙酸和环己醇为原料合成丙酸环己酯,并考察了影响反应的因素。结果表明：环己醇与丙酸物质的量之比为3：1,催化剂用量为1．4g（丙酸用量0．1mol）,带水剂为甲苯,用量为2mL,反应时间3．0h时,反应效果最佳,其酯化率可达90．9％。     

阶级分层：对当代中国社会分层的另一种解读——基于学理层面思考的中国阶级分层

卡尔·马克思的社会阶级理论仍然适合分析当代中国的社会分层。按照马克斯·韦伯的关于阶级和阶层是一个历史过程的观点，中国开始出现阶级现象；并尝试运用稀缺性生产要素占有关系解读当下的中国阶级状况及其相互关系；认为阶级分化或冲突并不必然会导致阶级对抗，阶级合作是现代社会的一个理性选择。     

Approaches to sample size calculation for clinical trials in rare diseases

We discuss 3 alternative approaches to sample size calculation: traditional sample size calculation based on power to show a statistically significant effect, sample size calculation based on assurance, and sample size based on a decision‐theoretic approach. These approaches are compared head‐to‐head for clinical trial situations in rare diseases. Specifically, we consider 3 case studies of rare diseases (Lyell disease, adult‐onset Still disease, and cystic fibrosis) with the aim to plan the sample size for an upcoming clinical trial. We outline in detail the reasonable choice of parameters for these approaches for each of the 3 case studies and calculate sample sizes. We stress that the influence of the input parameters needs to be investigated in all approaches and recommend investigating different sample size approaches before deciding finally on the trial size. Highly influencing for the sample size are choice of treatment effect parameter in all approaches and the parameter for the additional cost of the new treatment in the decision‐theoretic approach. These should therefore be discussed extensively.     

桥联双金属稀土配合物对丙交酯的催化聚合研究

本文研究了桥联双金属稀土配合物[(ArO)_2(DME)Sm]_2[μ-η~4-(PhN)OCCO(NPh)](其中 ArO=2,6-二叔丁基-4-甲基酚基)对丙交酯的催化聚合性能,讨论了催化剂用量、聚合时间、聚合温度及单体浓度的影响,还探讨了聚合反应机理。实验表明,聚合物粘均分子量可达10.0×10~4以上。     

On the Size Distribution of Macroeconomic Disasters

The coefficient of relative risk aversion is a key parameter for analyses of behavior toward risk, but good estimates of this parameter do not exist. A promising place for reliable estimation is rare macroeconomic disasters, which have a major influence on the equity premium. The premium depends on the probability and size distribution of disasters, gauged by proportionate declines in per capita consumption or gross domestic product. Long‐term national‐accounts data for 36 countries provide a large sample of disasters of magnitude 10% or more. A power‐law density provides a good fit to the size distribution, and the upper‐tail exponent, α, is estimated to be around 4. A higher α signifies a thinner tail and, therefore, a lower equity premium, whereas a higher coefficient of relative risk aversion, γ, implies a higher premium. The premium is finite if α > γ. The observed premium of 5% generates an estimated γ close to 3, with a 95% confidence interval of 2 to 4. The results are robust to uncertainty about the values of the disaster probability and the equity premium, and can accommodate seemingly paradoxical situations in which the equity premium may appear to be infinite.     

富铈混合稀土及锶对铸铝A356组织和力学性能的影响

本文通过加入不同富铈稀土变质剂和Sr对A356铸铝进行变质,分析了枝晶及共晶硅形貌,测试了几组材料的延伸率、拉伸强度和疲劳行为。试验及分析表明:变质剂对微结构的主要作用是改善了枝晶分布的均匀度,使共晶硅形态趋向短粗和圆棒状。随变质剂加入量的增加,A356合金的拉伸强度和延伸率逐渐增加。变质剂对A356铝合金的低周疲劳性能影响甚微,而提高了高周疲劳寿命。综合分析表明,变质剂对枝晶组织的均匀化和对共晶硅形貌的变化减小了初始缺陷尺寸,对疲劳裂纹萌生寿命的提高有显著影响。