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非线性光学晶体材料的研究进展

物理学进展 1993年第1期13卷 14-25页

作者：蒋民华山东大学晶体材料研究所济南250100

本文系统地介绍了我所在非线性光学晶体材料等方面的研究进展。

关键词：晶体生长光学晶体非线性光学

Structure evolution of cubic boron nitride under spark plasma sintering

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金刚石与磨料磨具工程 2008年第S1期28卷 165-167页

作者： Zhao Yucheng Wang Mingzhi (state key laboratory of Metastable materials Science and Technology, Yanshan university,Qinhuangdao 066004,china)

Cubic boron nitride(CBN) micro powders and mixture of CBN micro powders with Al or Ti powders were fast heated at 1 300,1 400,1 450,1 500℃,and then kept for 5 min under spark plasma sintering (SPS).The obtained powders were analyzed with *** results show that,simple CBN kept cubic structure after heated at 1 300℃;when the temperature rose to 1 400℃,some CBN was transformed into hexagonal structured boron nitride(hBN).As for CBN micro powders mixed with aluminum or titanium micro powders,the onset transforming temperature of CBN to hBN get *** results indicated that the structural transformation of boron nitride begun from the surface of CBN crystal particle,different coexist elements affect the surface situation of CBN *** the stabilities of CBN crystal particle surface improved,the onset structural transform temperature of CBN was also increased.

关键词： cubic boron nitride structure evolution transformation spark plasma sintering(SPS)

Alkali-silica Reactivity of Different Aggregates from Mineral and Textural Characteristics

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Journal of Wuhan university of Technology(materials Science) 2008年第6期23卷 901-906页

作者：莫祥银 Analysis and Testing Center & Jiangsu key laboratory of Biofunctional materials Nanjing Normal University

To identify the aggregates causing the alkali-silica reaction, and the reactivity of rocks in different parts of china, the mineral and texture characteristics of some typical coarse ag gregates and the alkali reactivity of these aggregates were systematically investigated. On one hand, petrographic examination of aggregates, combined with X-ray diffraction analysis, chemical analysis, scanning electron microscopy, was conducted for analyzing their mineralogy and texture. It was found that not only mineral characteristics, but also their interior structure would affect their potential alkali-silica reactivity. Furthermore, the alkali-silica reactivity of aggregates is due to their mineral compositions, such as containing different alkali-reactive minerals, while, different stuctures of those aggregates with similar minerals affect their reactivity to some extent. There are some amount of micro-aperture and cracks across the quartz in the aggregate, which may become the natural accesses for Na^＋, K^＋, and OH^- ions to intrude in the mortar or concrete during the process of alkali-silica reaction. Alkali-silica reactivity of the aggregates was detected by the accelerated mortar bars test. It was revealed that all the aggregates tested were alkali-silica reactive and the results were also in accordance with their mineral and structure analysis.

关键词： petrographic examination of aggregates study of thin sections x-ray diffraction analysis chemical analysis scanning electron microscopy

Leaf morphology correlates with water and light availability:What consequences for simple and compound leaves?

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Progress in Natural Science:materials International 2009年第12期19卷 1789-1798页

作者： Fei Xu,Weihua Guo~*,Weihong Xu,Yinghua Wei,Renqing Wang~* institute of Ecology and Biodiversity,College of Life Sciences,shandong university,jinan 250100,china [a]institute of Ecology and Biodiversity College of Life Sciences Shandong University Jinan 250100 China

Leaves are organs sensitive to environmental changes in the process of evolution and may exhibit phenotypic plasticity as a response to abiotic ***,affirmation of leaf morphological plasticity and its regulations in different environments are still *** performed a simulated experiment to study the variations of leaf morphology in different gradients of water and light *** different types of leaves and venation,we chose pinnate-veined simple leaves of Quercus acutissima and compound leaves of Robinia pseudoacacia as the study *** morphological parameters we investigated include leaf size,shape and venation pattern which can be easily measured in the *** variations occurred in many parameters due to the effects of the environment and/or *** were broadly consistent trends for leaf morphological variations along the *** leaf size became smaller with a short supply of *** elongation and fractions of the lamina area altered to enhance resources acquisition and conservation. Trade-offs between investments in support and functional structures optimized the venation pattern of major and minor *** partially played a role such as leaf teeth,for they are not only individual units,but also a part of the compound *** suggest that more or less the same trends in morphological variations may be an important explanation for coexisting species to adapt to similar habitats and form the niche differentiation.

关键词： Environmental correlation Leaf morphological trait Leaf type Venation pattern Quercus acutissima Robinia pseudoacacia

Three-dimensional coherent diffraction imaging of Mie-scattering spheres by laser single-orientation measurement

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Chinese Physics B 2015年第9期24卷 11-15页

作者：张剑范家东张建华孙智斌黄庆捷江怀东 state key laboratory of crystal materials Shandong University School of Information Science and Engineering Shandong University

Three-dimensional imaging with single orientation is a potential and novel technique. We successfully demonstrate that three-dimensional（3D） structure can be determined by a single orientation diffraction measurement for a phase object of double-layer Mie-scattering silica spheres on a Si3N4 membrane. Coherent diffraction pattern at high numerical aperture was acquired with an optical laser, and the oversampled pattern was projected from a planar detector onto the Ewald *** double-layered spheres are reconstructed from the spherical diffraction pattern and a 2D curvature-corrected pattern,which improve convergence speed and stability of reconstruction.

关键词： coherent diffraction imaging phase retrieval laser

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双轴晶体有效倍频系数的计算

中国激光 1991年第2期18卷 156-160页

作者：尹鑫山东大学晶体材料研究所 250100

1975年,Hiromasa Ito等人讨论了双轴晶体,有效倍频系数的计算问题,给出了解决这一问题的正确思想。王恭明等人曾指出了文献[1,2]中关于坐标系选取的问题,并以mm2点群为例作了详细的讨论。以前的工作都忽略了基频波与倍频波δ值的不同,... 详细信息

1975年,Hiromasa Ito等人讨论了双轴晶体,有效倍频系数的计算问题,给出了解决这一问题的正确思想。王恭明等人曾指出了文献[1,2]中关于坐标系选取的问题,并以mm2点群为例作了详细的讨论。以前的工作都忽略了基频波与倍频波δ值的不同,也没有考虑基频光电位移矢量D和电场强度矢量E的离散效应。本文讨论了这些问题后,给出双轴晶体五种点群在主光轴坐标系中有效倍频系数的计算公式。

关键词：双轴晶体倍频计算激光材料晶体

Recent Development on the Mechanism Research of crystal Growth

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Science Foundation in china 2002年第2期10卷 26-30页

作者： Yu Xiling Wan Yan( The state key Lab of crystal materials of shandong university, Ji ’nan 250100 Physics Department of Shanghai university, Shanghai 200436)

Recent developments on the research of growth mechanism by two -dimensional nucle-ation, dislocation, normal and three -dimensional nucleation are reviewed: the latest research work on the structure adjusting in the i... 详细信息

关键词： crystals growth mechanism structure adjusting growth unit

Modeling and Estimation of the Kinetics of Seeded Solvent-mediated Phase Transformation in a Batch crystallizer

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Journal of Wuhan university of Technology(materials Science) 2011年第5期26卷 872-878页

作者：唐明亮沈晓冬 state key laboratory of materials-Oriented Chemical Engineering College of Materials Science and EngineeringNanjing University of Technology

Modeling the kinetics of the preparing process is necessary to produce a product with the appropriate particle properties and minimum production *** to the lackness of crystal size distributor （CSD） information,however,solvent-mediated phase transformation encounters difficulty in modeling the kinetics as compared to solution ***,a model was established by making the product CSD to move along by horizontal translation to obtain the CSDs of the stable phase in the process of *** the moment method was used to solve the popular balance equation,and the least square nonlinear regression method was applied to estimate the kinetics *** model has been successfully used to simulate the transformation of CaSO4？2H2O to α-CaSO4？1/2H2O in an isothermal seeded batch crystallizer with different stirring speeds,and it is beneficial to producing high performance α-CaSO4？1/2H2O crystals which have the right particle characteristics.

关键词： solvent-mediated crystallization kinetic modeling CSD calcium sulfate

Effect of Cerium on the Viscosity of Liquid Fe-C Alloy of Eutectic Content

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Journal of Rare Earths 2002年第6期20卷 630-634页

作者：滕新营叶以富key laboratory of Liquid Structure and Heredity of materials Ministry of Education South Campus of shandong university 刘含莲王焕荣石志强耿浩然 key laboratory of Liquid Structure and Heredity of materials Ministry of Education South Campus of Shandong University College of Mechanical Engineering Shandong University

The viscosities of liquid Fe-4.30C and Fe-4.30C-Ce alloys were measured by oscillating crucible viscometer. The results show that viscosity of Fe-4.30C alloy changes from 5.50 to 8.30 MPa·s when the liquid is cooled from 1425 ℃ to the melting point. The abnormity of viscosity of Fe-4.30C alloy near the melting point is reasonable due to the formation of graphite. The addition of cerium especially with content higher than 0.21% causes an evidently decrease in viscosity for eutectic alloy resulting from increase of free volume and size decrease of atom cluster in the liquids. It can be concended that the existence of C-Ce compound contributes to the discontinuous of viscosity at 1340～1370 ℃ for the Fe-4.30C-Ce alloy by experinments with differential scanning calorimeter.

关键词： rare earths cerium viscosity liquid eutectic Fe-C alloy