Microtextures Formed by the Remelting Reaction in Belite Crystals

When they are cooled below the stable temperature region of the α phase, crystals of belite (Ca₂SiO₄ solid solutions) inverted to the α'_H phase without a change in chemical composition and gave six sets of lamellae within the crystals. After this transition remelting reaction occurred within the inverted α'_H-phase grains, the liquid phase became nucleated and grew heterogeneously on the lamellae boundaries, resulting in a decrease in impurity concentration in the host α'_H phase. When the exsolved liquid wetted the lamellae, complete dissolution of the parent crystals occurred during slow cooling. A variety of microtextures resulted, depending on both quenching temperature and cooling rate.     

Compaction-Induced Anisotropy in Internal Structure of Ceramic Powder

Biaxial compaction is carried out for two ceramic powders using a plane-strain compaction device with various loading paths. It is thus shown that anisotropy is induced into a powder mass undergoing unequal biaxial stresses. A trial to evaluate some experimentally based parameters for the induced anisotropy is carried out. A model for the development of anisotropic powder structure is suggested, and expressions for a measure of the anisotropy are derived. Experimentally measured values of stresses and elastic strains are used to calculate the values of the anisotropic parameters. Anisotropy is also observed in the subsequent sintering behavior.     

基于X光移动光刻技术的PMMA微透镜阵列制备

微透镜阵列的制备已经成为微光学领域的研究热点。利用两次X光移动光刻技术,以聚甲基丙烯酸甲酯(PMMA)为正光刻胶,在PMMA基板上制造了微透镜阵列,并对其制作原理进行了详细说明。设计了制备微透镜阵列用的掩膜图形,并通过掩膜图形模拟仿真,预测了微透镜在两次移动曝光显影后的形状。第一次X光移动光刻后,理论上会得到半圆柱状三维结构;第一次光刻后将掩膜板旋转90,进行第二次移动曝光光刻,最终在PMMA基板上制备了面积为10 mm10 mm的3030个微透镜阵列,阵列中每个微透镜的直径约248m、厚度约82m。同时也研究了X光曝光量与PMMA刻蚀深度之间的关系。微透镜阵列形貌测试表明此种制备微透镜阵列的新方法是可行的。     

Studies on Starch Phosphate Part 1. Estimation of glucose-6-phosphate residues in starch and the presence of other bound phosphate(s)

The phosphorus of glucose-6-phosphate residue in starch (P(G6P)) was estimated specifically by means of glucose-6-phosphate dehydrogenase (E.C.1.1.1.49) after acid hydrolysis. Sixty to 70 % of total phosphorus in potato starch was found to be P(G6P)). It was shown that the rest of phosphorus (Px) was incorporated as glucose-2-phosphate and/or glucose-3-phosphate, since it was determined as glucose by periodate oxidation, borohydride reduction, acid hydrolysis and treatment with alkaline phosphatase. The Px was more labile to acid and heat than P(G6P) and decomposed yielding inorganic phosphate. The phospholigosacharide (D. P. 3.6), which was prepared by the limit hydrolysis of potato starch with glucoamylase of Rh. delemar (α-1,4-Glucan glucohydrolase E.C.3.2.1.3) was fractionated by gel-filtration through Sephadex G-25 into fractions with D.P. 2 to 7. Each fraction contained a mole of phosphorus per mole of the saccharide. The P(G6P) and the Px were enriched in the low and the high D.P. fractions, respectively.