Examples of entropy generating sequence

We introduce the notion of entropy generating sequence for infinite words and define its dimension when it exists. We construct an entropy generating sequence for each symbolic example constructed by Cassaigne such that the dimension of the sequence is the same as its topological entropy dimension. Hence the complexity can be measured via the dimension of an entropy generating sequence. Moreover, we construct a weakly mixing example with subexponential growth rate.     

Pseudo-relaxor behaviour induced by Maxwell–Wagner relaxation

We performed a further investigation on the Maxwell–Wagner (MW) relaxation-induced relaxor-like dielectric response characterized by a broad peak in the real part of the dielectric permittivity as a function of temperature. Based on the double-layer MW model formulated by Catalan et al. (2000) [10], an empirical formula was derived to describe the temperature dependence of the peak intensity. It was also found that the temperature dependence of the peak position can be characterized by an Arrhenius-like relation. The differences between the true relaxor and MW-related relaxor behaviours are also discussed.     

低价钛试剂促进下苯并咪唑并[1,2-c]喹唑啉衍生物的合成

在低价钛试剂促进下,以2-（2-硝基苯基）苯并咪唑和碳酸二三氯甲酯为原料,经过串联还原偶联反应,一步合成了一系列苯并咪唑并[1,2-c]喹唑啉-6（5 H）-酮衍生物.产物结构通过红外光谱、核磁共振氢谱和元素分析确证.     

竞走教学法初探

本文对竞走教学中的技术教学与素质训练、用力方法和自我肌肉感觉等关系做了探讨和详细的论述。还对竞走运动员的步长进行了计算与分析。     

多效唑在棉花上残留量的初步研究

本试验在整个棉花生长期喷施多效唑溶液两次，６０天后（收获期），用气相色谱法测定多效唑在棉花植株各部位和土壤中的残留。其结果为：土壤、籽、茎中残留的量未检出，叶、根、壳中的残留量分别为１．２０６，０．３６７，０．４８５ｍｇ／ｋｇ。     

Stable conformations of 12-crown-O3N and its Li+ complex in aqueous solution

Stable conformations of 12-crown-O3N and its Li complexes in aqueous solution were investigated. To calculate the free energy differences of conformers of 12-crown-O3N and its Li+ complex, our procedure was to make use of two programs, CONFLEX and BOSS. The former generates conformers, and the latter calculates the differences in free energy of solvation between two conformers in aqueous solution. It was confirmed that the present procedure is applicable in solving the question of what is the most stable conformation of 12-crown-O3N in aqueous solution. Results of the calculations suggest that the order of stability for conformers in a vacuum is different from that in aqueous solution. It was also confirmed that the coordination geometry of solvent waters to Li+ changes depending on the distance between the cation and the crown ring.     

Synthesis of a new meso／microporous composite molecular sieve of MCM-41／mordenite

An MCM-41/mordenite composite with twofold porous structure and stepwise-distributed acidity was prepared for the first time by using zeolite mordenite as the silica-alumina source. The composite molecular sieve has been investigated and compared with a mechanical mixture of mordenite and MCM-41 for their structure, acidity and catalytic activity by means of XRD, N2 adsorption and desorption, HRTEM, DTG, NH3-TPD and catalytic reaction. The characterization results show that the structure and property of the composite molecular sieve are quite different from those of the mechanical mixture, which might be ascribed to the incorporation of secondary building units characteristic of zeolite mordenite into the mesoporous walls of the composite which gives rise to the thicker mesoporous walls, the higher hydrothermal stability and more strong acid sites. Furthermore, the new strategy could be used as a new general method for the preparation of catalysts for the reaction system with multifold large molecules, and the results were well confirmed by the dealkylation of C10^ aromatic hydrocarbon.     

论高校人才培养成本

高等学校人才培养成本是高等学校管理者必须关注的问题之一。在列举了构成办学成本要素的基础上 ,对其进行了定量与定性分析。提出了既不能追求成本最小而导致投入不足影响教育质量 ;也不能一味投入而造成成本失控。应该保证教育资源尽可能满足教育质量以达到最优的需要