石英晶体碱(KOH)腐蚀像及其与酸(HF)腐蚀像对比研究

本文用KOH溶液对石英晶体进行腐蚀实验.对石英晶体不同结晶学方向的5个品面(切面)的腐蚀像进行观察,建立了石英碱腐蚀形貌的立体模型,并与酸(HF)溶液所腐蚀的同样5个面的腐蚀像进行对比.研究发现碱腐蚀与酸腐蚀在柱面{1010}和菱面{1011}、{0111}上有很人不同,在柱切面{1120}、{2110}上有相同之处.但它们都反映各品面及晶体的对称特点.该研究对揭示矿物晶体在不同酸碱地质环境下腐蚀的特点具有指导意义.     

Orientation relationship in various 9%Cr ferritic/martensitic steels–EBSD comparison between Nishiyama–Wassermann,Kurdjumov–Sachs and Greninger–Troiano

EBSD measurements were carried out on four different martensitic steels (T91, P92, EM10 and Eurofer) in various metallurgical conditions (nine different microstructural states). The usual orientation relationships (ORs) between the parent austenitic phase and the resulting martensite in martensitic steels are those of Nishiyama–Wassermann (NW) and Kurjumov–Sachs (KS). The present study first proposes a methodology based on the combined analysis of the misorientation distribution, the pole figures (PFs) and the angle/axis pairs. This methodology leads to the conclusion that neither NW nor KS relationships are able to account for all the features observed whatever the material under study. A third OR proposed by Greninger and Troiano (GT) proves to describe the relationship between austenite and ferrite in all four different martensitic steels much more accurately.     

孔隙率及晶粒尺寸对多孔PZT陶瓷介电和压电性能的影响及机理研究

采用添加造孔剂的方法制备多孔锆钛酸铅(PZT)陶瓷,并研究了孔隙率和晶粒尺寸对多孔PZT陶瓷介电和压电性能的影响及机理.研究表明：孔隙率的增加降低了多孔PZT陶瓷的介电常数,提高了静水压优值,并证明在一定条件下孔隙率与介电常数关系可由Okazaki经验公式及Banno模型预测;晶粒尺寸增加,多孔PZT陶瓷的介电常数、压电系数和优值增加,并可用Okazaki空间电荷理论解释晶粒尺寸对试样介电和压电性能的影响.对于添加重量百分数为10%造孔剂的多孔PZT陶瓷,当烧结温度为1300℃时,孔隙率为34%,d关键词：多孔PZT陶瓷静水压优值压电性能介电性能     

The predawn of paper chromatography

Summary The activities of F.F. Runge, F. Goppelsroeder and R.E. Liesegang are outlined. The technique of capillary analysis is described and its shortcomings elaborated. Tswett's use of filter paper to imitate plant tissues is explained and finally, the considerations of Izmailov and Shraiber eventually leading to thin-layer chromatography are summarized.     

Equivalence Relations from a Geometrical Point of View

ＥｑｕｉｖａｌｅｎｃｅＲｅｌａｔｉｏｎｓｆｒｏｍａＧｅｏｍｅｔｒｉｃａｌＰｏｉｎｔｏｆＶｉｅｗ￥ＣｈｅｎＺｈｅｎｇｔｉｎｇ（ＬｕｏｙａｎｇＥｄｕｃａｔｉｏｎａｌＩｎｓｔｉｔｕｔｅ）Ａｂｓｔｒａｃｔ：ＷｅＰｒｏｖｅａｔｈｅｏｒｅｍａｂｏｕｔｔｈｅｇｅｏ...