有限交换环上极限线性群的Sylowp—子集

本文给出了有限交换局部环Ｒ上无限线性群ＧＬ（Ｒ）＝∪ｎＧＬｎＲ的Ｓｙｌｏｗｐ－了群的形式。令Ｍ是有限交换局部环Ｒ的唯一极大理想，ｋ＝Ｒ／Ｍ为Ｒ的剩余类域。用ｘ（ｋ）表示ｋ的特征，并假定ｐ与ｘ（ｋ）互素。     

铯原子永久电偶极矩实验研究

圆柱形电容器中充铯蒸气,测量不同温度下电容量的变化,这变化与铯原子数度成正比。本实验得出铯原子永久电偶极矩edCs>2.4e×10-8cm。     

理科(21)题文科(22)题别解

试题已知常数a＞0,在矩形ABCD中,AB=4,BC=4a,O为AB中点,点E、F、G分别在BC、CD、DA上移动,且(BE)/(BC)=(CF)/(CD)=(DG)/(DA),P为GE与OF的交点(如图8).问是否存在两个定点,使P到这两点的距离和为定值?若存在,求出这两点的坐标及此定值;若不存在请说明理由.     

Aspect实验与两位科学巨人的争论--兼对批评的回答

指出Aspect实验同玻尔与爱因斯坦之间的巨人之争密切相关,阐述了玻姆思想实验与贝尔不等式的重要意义.     

长链烷氧基取代金属卟啉／H2O2体系催化烯烃环氧化反应研究

长链烷氧基取代金属卟啉／Ｈ_２Ｏ_２体系催化烯烃环氧化反应研究肖友发，游劲松，余孝其，虞小华，蓝仲薇（四川大学化学系成都６１００６４）关键词长链烷氧基金属卟啉，过氧化氢，烯烃，环氧化反应具有疏水结合部位的金属卟啉，如甾体一金属卟啉［１］、环糊精一金属卟...     

双恶唑啉化合物偶联聚酯的研究：II.聚对苯二甲酸乙二酯的偶联反应

用特性粘度（［η］）和羧值为参数，研究了双恶唑啉化合物（ＢＯＺ）对聚对苯二甲酸乙二酯（ＰＥＴ）的扩链反应动力学过程，表明ＢＯＺ是与ＰＥＴ中羧基反应，考察了不同工艺生产的ＰＥＴ的扩链效果，结果说明达到的［η］极大值取决于原始ＰＥＴ的［η］与羧值之比。     

高分子负载锰卟啉的合成及其催化烯烃环氧化反应研究

本文用羟基取代四苯基卟啉锰通过醚键与聚苯乙烯树脂键联，合成了一类高分子负载化锰卟啉化合物。经ＥＳＲ、ＩＲ、ＵＶ－ｖｉｓ散射光谱等测定证实其结构。本文同时考察了它们对烯烃环氧化反应的催化活性，结果表明，负载化金属卟啉在催化烯烃环氧化反应中能集均相和多相催化的优点于一体，不仅催化剂稳定性增强，而且易于分离和重复使用。     

Effects of heat transfer in a growing particle layer on microstructural evolution during solidification of colloidal suspensions

Heat transfer is the foundation of freezing colloidal suspensions and a key factor for the interface movement.However,how the thermal conductivity of particles affects freezing microstructural evolution remains unknown.Here in this work,a mathematical model is built up to investigate thermal interactions among a growing particle layer,pulling speeds,and the freezing interface under a thermal gradient.Experiments are conducted to confirm the tendency predictions of the model.With the increase of pulling speeds,the drifting distance of the freezing interface increases and the time to finish drifting decreases.When the thermal conductivity of particles(k_p)is smaller than that of the surrounding(kw),the freezing interface tends to go forward to the warm side.Contrarily,the freezing interface tends to go back to the cold side when the thermal conductivity of particles is larger than that of the surrounding(α=k_p/k_w>1).It originates from the shape of the local freezing interface:convex(α<1)or concave(α>1).These morphological changes in the local interface modify the premelting drag force F_f.Whenα<1,F_fdecreases and the freezing morphology tends to be the frozen fringe.Whenα>1,F_fincreases and the freezing morphologies tend to be ice spears.These understandings of how the thermal conductivity of particles affect microstructural evolution may optimize the production of freeze-casting materials and their structural-functional properties.