反复载荷

The experimental result shows that under a warm temperature and large load, the initial features of structure and fabric disappear finally, and a small circle girdle fabric with fine equigranular grains appears, and a mult-maxima fabric developes to some extent.

结果表明，在较高的温度和大载荷下，样品经反复压缩-退火，其初始组构特征消失，代之以小环状组构和细的、等粒的晶体，某些情况下发展为多极大型组构。

The mechanical performance of garbage is uncertain, now there isnt any thesis about garbage and the load of garbage to box of compressed garbage truck.

本文经反复研究试验给出了车箱内垃圾载荷的数学表达，并通过有限元分析结果和实验数据的比较验证并完善了这些数学表达的合理性。

And because of its serious peeling and deforming, the production of mill machine-hour is affected, it is not good for using.

因为贝氏体具有硬度较高、机械性能较好的综合性能，奥氏体在反复冲击载荷下有加工硬化现象，使用中&外硬里韧&，因此，这两种基体组织的高铬球应该是最佳研磨体。

AbstractObjectives1 Correlate bone mineral densityto vertebral compressive strengths.2 Consummate the technique for percutaneous polymethylmethacrylate vertebroplasty and observe the pattern of PMMA imaging distribution.3 Determine the strength and stiffness of osteoporotic with or without vertebroplasty with PMMA bone cement.4 Correlation of BMD,insertion torque and pull-out strengths of pedicle screws.5 Ascertain whether augmentation with PMMA bone cement can enhance pedicle screw fixation in the osteoporotic spine.6 Ascertain whether augmentation pedicle screw fixation with PMMA bone cement can enhance the stability of unstable thoracolurner burst fractures of osteoporotic spine.

目 的1、测试椎体压缩强度，分析强度与骨矿物质密度（bone mineral density，BMD）的相关关系。2、观察经皮椎体成形术后聚甲基丙烯酸甲脂（polymethylme- thacrylate，PMMA）骨水泥在椎体内的形态学分布及影像学表现。3、比较PMMA骨水泥骨质疏松椎体成形术前/后椎体最大抗压力和压缩刚度的变化。4、分析椎体BMD、螺钉最大旅入力矩和最大拔出力三者之间的关系。5、分析PMMA骨水泥强化骨质疏松椎弓根螺钉后的螺钉的最大轴向拔出力和拔出刚度的变化。6、评价PMMA骨水泥强化骨质疏松椎弓根螺钉脊柱内固定对不稳定型胸腰椎损伤的即刻稳定性和反复载荷后的稳定性。

According to the clear water experiment, aeration performance of the new equipment is good with high total oxygen transfer coefficient and oxygen utilization ratio.

曝气设备的动力效率在叶轮转速为120rpm～150rpm时取得最大值，此时氧利用率和充氧能力也具有较高值。

The environmental stability of that world - including its crushing pressures and icy darkness - means that some of its most famous inhabitants have survived for eons as evolutionary throwbacks, their bodies undergoing little change.

稳定的海底环境─包括能把人压扁的压力和冰冷的黑暗─意谓海底某些最知名的栖居生物已以演化返祖的样态活了万世，形体几无变化。