晶粒

School of Chemistry and Chemical Engineering, Central South University, Changsha 410083, China）Abstract: By analyzing the crystal growth habit of gibbsite theoretically using Morphology program, the morphology character of crystal grain and the theoretic habit of gibbsite were studied.

摘 要：对氢氧化铝晶体生长习性进行Morphology理论研究，明确氢氧化铝晶粒长大后的晶粒形态特征及氢氧化铝的理论晶体生长习性。

Increasing with the increment of grain size at nucleation side, the thermal conductivity is increased.

形核面晶粒尺寸越大，晶粒间的晶界就减少，有利于提高金刚石自支撑膜的热导率。

Comparisons of flow curves, microstructure evolution, distribution of average grain size and number of grain side in final microstructure show that the simulated results agree very well with the experimental ones, suggesting that the present CA model is feasible to study the DRX process of AZ91 alloy.

对比分析应力—应变曲线、组织演变、稳态组织中的平均晶粒尺寸及晶粒边数分布，模拟结果与实验结果的良好一致性表明本文作者提出的元胞自动机模型可以用于AZ91合金动态再结晶过程的模拟研究。

The microstructure in the heat--affected zone consists of coarse bar-shape recovery grain, and that of the thermo-mechanically affected zone exhibits bent band-like character, but the deformation degree at the advancing side is bigger than that at the retreating side. Microstructures in TMAZ are also recovered, and the amount of recovery grain at retreating side is more than that at advancing side.

热影响区组织发生回复和粗化反应，形成粗大的棒状回复晶粒；热机影响区组织发生弯曲变形，但整体上仍保留带状组织形貌，前进侧热机影响区组织变形程度高于后退侧，该区同时还发生回复反应，且后退侧热机影响区内的回复晶粒数量多于前进侧。

The grain boundary structure in these nanostructured materials is similar to that of the conventional coarse grained materials.

在这些纳米结构材料中的晶粒边界结构与传统的粗晶粒材料的结构相似。

The results indicate that the flow stress of the alloy increases with increasing strain rate and decreasing deformation temperature. The flow stress increases with increasing strain until the stress reaches the peak value, then the flow stress remains constant, which indicates that dynamic recrystallization happens during deformation. The flow behaviors are described by the hyperbolic sine constitutive equation, and the activation energy calculated is 337.75 kJ/mol. The as-forged microstructure consists of refined α2/γ and γ grains, and the grains are much homogeneous than before. The B2 phase distributes uniformly at the grain boundary of α2/γ and γ grains. The B2 phase decreases with increasing deformation temperature.

结果表明：流变应力随着应变速率提高和变形温度降低而增大；在变形过程中，流变应力随着变形量增大而增大，当流变应力达到峰值后趋于平稳，表明合金在变形过程中发生了动态再结晶；热变形过程的流变应力可采用双曲正弦本构关系来描述，平均激活能为337.75 kJ/mol；从合金的组织演化过程中可以看出，合金中不均匀的原始组织得到明显均匀化，变形后的组织是由α2/γ层片晶团和γ晶粒组成的双态组织，在α2/γ层片晶团和γ晶粒的晶界交界处发现分布均匀的B2相，并且随着变形温度升高B2相数量逐渐减少。

The withstand voltage of a single grain was induced to indicate the withstand voltage properties of grain boundary.

本文建立了PTCR 材料的晶界、晶粒微观模型，采用单晶粒的耐压强度表征PTCR 材料的耐压性能。

The films show large crystalline size and high orientation degree.The structure characteristics were examined with X-ray diffraction and electronic microscope as functions of the ionization current and acceleration voltage.

在单晶Si及玻璃衬底上演积的CdTe膜具有定向生长的大晶粒结构，其晶粒尺寸、取向度与离化电流、加速电压等可控实验参数之间的关系在实验结果中得到了反映。

He fracture surface observed by SEM has lamella structure, making the strength increase distinctly.

EM和SEM观察发现钢板的层状晶粒在高于550℃退火后转变成等轴超细晶粒组织，且该结构可以阻碍裂纹的扩展，使钢板的强度得到显著提高。

The results show that the interplanar crystal spacing and lattice index of Al-rich α phase reduce gradually with increasing pressure. When the pressure reaches from common pressure to 5 GPa , Al-rich α phase lies on the (200) and (220) crystal faces, the interplanar crystal spacing are reduced by 1.07% and 1.15%. From common pressure to 3 GPa , the microstructure of ZA27 alloy changes from thick dendrites to fine dendrites, and finally to granular. According to the effect of solute diffusion coefficient under super high pressure and the calculation of Scherrer formula, it can be seen that the crystal organization is fine within the bounds of certain pressure. This conclusion is consistent with the experiment results.

结果表明：随着压力的增加，晶面间距和晶格常数都逐渐减小，当压力达到5 GPa时，富铝α相在(200)与(220)晶面处，晶面间距较常压力时的分别减小1.07%和1.15%；在常压至3 GPa范围内，晶粒由粗大的树枝晶→细小的树枝晶→粒状、椭球状枝晶转变的趋势，通过压力对合金凝固溶质扩散系数的影响结合Scherrer公式计算分析其组织变化原因，得出在一定的压力范围内，随着压力的增大，晶粒尺寸逐渐变小，这一结论与实验结果相符。

Fancy gold-plated dangling earrings with facetted White Opal crystals.

花式镀金悬垂耳环与facetted白欧泊水晶。

This essay chooses the study aim from biology teachers in middle school in Shi Jiazhuang which tells us that most of the middle school biology teachers in Shi Jiazhuang have the"burnout", lower successfulness, individualize.

本文选取石家庄市初中生物教师作为研究对象，运用问卷调查的方法对石家庄市初中生物教师职业倦怠的现状进行调查，调查结果发现，石家庄市初中生物教师这一群体普遍存在职业倦怠，情感枯竭程度偏高，成就感偏低，去个性化程度最为严重。