多晶现象

Cathodoluminescence and δ〓O、δ〓C values of the sparites of geopetal structures within fossil brachiopods indicate that the sparcalcites were formed in equilibrium with various stages of postdepositional digenesis or catagenesis with each stage's δ〓O of interstitial water different.

3碳酸盐岩早期成岩胶结物或孔洞充填中的亮晶方解石是除腕足化石外获取碳酸盐岩原始氧、碳同位素组成的又一种常用样品。但本论文研究发现，龙门山地区碳酸盐岩的成岩后生改造具有多期多次现象，不同改造期次的流体之间存在明显的δ〓O差异，但无明显的δ〓C差别。

It is important to measure the solubility of different forms of glycine for studying crystallization and polymorphism of glycine.

不同晶型甘氨酸溶解度的测定对研究甘氨酸结晶及多晶型现象具有重要意义。

This project is going to investigate the crystallization of polymers in scCO2 and to study the polymorphism and solid-phase transition of crystallizable polymers with different molecular structure and different tacticity in scCO2 for accumulating the fact of crystallization of polymers in the titled surrounding, revealing the rule of solid-phase transition of polymers in scCO2 and exploring the mechanism responsible for these phenomena.

本项目研究聚合物在scCO2中的结晶行为，研究不同分子结构、不同等规程度聚合物的同质多晶现象与固相转变，积累现象、寻找规律、探求机理。

All the complex series based on 4',4''-dicarboxy-1,6-diphenoxyhex- ane (C6-2COOH) and 4',4''-dicarboxy-1,10-diphenoxydecane (C10-2COOH) possessed higher melting and clearing points, usually showed soft crystal or crystalline smectic phases and crystal polymorphs except C10-2COOH/ p -PhBPy complex displaying also an enantiotropic nematic phase, while the complexes based on 4,4'-dicarboxy-α,ω-diphenoxy tetraethyleneglycol ether (C8O4-2COOH) with a longer flexible spacer exhibited monotropic fluidic smectic SmA and/or nematic phases.

研究表明，分别具有较短的6或10个亚甲基的烷烃间隔基的双苯甲酸衍生物4'，4''-二羧酸-1，6-二酚氧基己烷(C6-2COOH)和4'，4''-二羧酸-1，10-二酚氧基癸烷(C10-2COOH)的系列复合物具有较高的熔点和清亮点，一般都只出现结晶近晶相和多晶型转变现象。

Starting with the toughening of ceramics, the subcritical crack growth model on monotonical loads was set up for the first time, and the V—K curves in the subcritical crack growth process and the effects on them were obtained by use of computer simulation.

首次从材料增韧入手，建立了单向载荷形式下亚临界裂纹扩展模型，并利用计算机数值计算获得裂纹扩展过程中V—K曲线及其影响因素，由此对多晶陶瓷材料疲劳现象的本质进行了分析。

In the case of granite, observation results indicate that the extending routes of active cracks are mainly intercrystalline, transcrystalline, inter-transcrystalline, and intracrystalline. When the strain rate is low, the long intercrystalline cracks are prevailing, and with increasing of the strain rate, the short transcrystalline and intracrystalline cracks gradually increase. The statistic results show that the active crack density increases with increasing of the strain rate, and the mean length of active cracks diminishes with increasing of the strain rate, that is, the induced damage in comminuted product increases with increasing of the strain rate. For the first time this dissertation integrates macroscopic results of comminution with active crack growth under impact loading. It elucidates why the dynamic comminution strength of mineral beds increases with increasing of the strain rate through the active crack extending, and analyzes the influence of structure and constitution of minerals on their damage under impact stress. It is authenticated that both the size distribution and the damage population of comminuted product can be characterized by the fractal.

为分析料层颗粒在冲击下的细观损伤效果，采用德国生产的ASM68K半自动图象分析仪对粉碎生成物中的损伤情形进行了观测，以花岗岩为例，观测结果表明花岗岩颗粒在冲击应力下的活化裂纹扩展路径主要表现为沿晶、穿晶、沿穿晶和晶内等形式，在低应变速率下，活化裂纹以沿晶裂纹较多，随着应变速率的提高，其它裂纹形式大量繁衍，统计结果表明活化裂纹密度随着应变速率的增大而增大，活化裂纹的平均长度随着应变速率的增大而减小，综合表现为颗粒的细观损伤程度随着应变速率的增大而增大；首次将应力作用下的活化裂纹演化特征与粉碎的宏观效果相联系，并就料层动态粉碎强度随应变速率增大而提高的现象从裂纹演化特征的角度进行了解释；分析了矿岩构造结构特性对损伤产生和分布的影响。

Main results are listed as below: 1. In rapid solidification, when the cooling rate is over some critical value, the solidification system will become unstable in the sense of the nonequilibrium thermodynamics, a uncontinuous steady state jump phenomenon will occur, and this uncontinuous steady state jump can be understood as the glass transition.

主要得到了如下结果：(1)通过对快速凝固过程的动力学及热力学的分析，提出了非晶转变的分枝理论模型，结果表明，对一合金熔体，当冷却速度大于某一临界值时，凝固体系会出现非平衡热力学意义上的失稳而出现多定态分枝现象，这一多定态现象可以被理解为非晶转变。

SiC polytypes of 6H and 15R and a transition zone between the two were observed under HREM and TEM and discussed from the point view of the crystal structures; the clear evidence of Al〓C〓 nucleated in the SiC particle was provided, indicating the aluminum penetrating the SiC grains is already carbon-saturated and, consequently, Al〓C〓 crystals grow in the particles wherever a temporary local supersaturating is produced; The experimental observation indicated that the types of the interface between SiC and Al are variable and the distribution feature of reaction product, Al〓C〓, were also given in the present work: to be nucleated on SiC, to be aggregated at SiC/Al interface zone or to be aggregated at the crystal boundaries.

通过高分辨透射电镜，本文观察到SiC增强体中6H和15R同质多晶现象及6H-15R SiC转变区，以及另外一种无序的SiC同质多晶，并从其晶体结构的角度解释了6H和15R在晶体内共存的现象。通过高分辨透射电镜，本文给出了Al〓C〓在SiC颗粒内部形核的明证，表明Al〓C〓形核是Al渗透到SiC颗粒内部在C过饱和处在SiC的（0006）面上而形核，而且一种可能的位相关系为A1〓C〓[11〓0]∥SiC[11〓0]。研究结果同时给出了SiC/Al复合材料的界面反应产物A1〓C〓的分布特征：在SiC上形核并生长，聚集于SiC/Al界面去附近，或者聚集于晶界上。

Compared with polycrystalline Cu, the as-cast single crystal copper shows better plasticity and extensibility, and has a lower electricity resistance. Its elongation of cold rolling can reach 6100% without any cracks in the edges. The single crystal copper exhibits more serious work hardening in wiredrawing. The plasticity and ...

结果表明：和多晶铜相比，单晶铜在铸态时具有良好的塑性和较低的电阻率，并具有优异的室温延展性，其延伸率可达 6 10 0 %以上；冷拉拔加工后单晶铜表现出更大的加工硬化现象，但采用合理的退火工艺可使其加工硬化得到缓解。

In this paper, digital speckle pattern metrology has been applied to the direct observation and measurement of PLC shearing deformation bands. A systematic research, including experimental observation and numerical simulation, on the PLC effect in Al-Cu polycrystals during tension has been carried out at room temperature.

本文将数字散斑计量技术应用于对PLC变形带的直接观测，对室温下多晶铝合金材料拉伸过程中的动态应变时效现象开展了系统性的研究，并结合实验结果进行了数值模拟和分析。

It has been put forward that there exists single Ball point and double Ball points on the symmetrical connecting-rod curves of equilateral mechanisms.

从鲍尔点的形成原理出发，分析对称连杆曲线上鲍尔点的产生条件，提出等边机构的对称连杆曲线上有单鲍尔点和双鲍尔点。

The factory affiliated to the Group primarily manufactures multiple-purpose pincers, baking kits, knives, scissors, kitchenware, gardening tools and beauty care kits as well as other hardware tools, the annual production value of which reaches US$ 30 million dollars.

集团所属工厂主要生产多用钳、烤具、刀具、剪刀、厨具、花园工具、美容套等五金产品，年生产总值3000万美元，产品价廉物美、选料上乘、质量保证，深受国内外客户的青睐