半自动的

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。

This paper narrates the usage and maintenance of semi-automatic CO2 welding torch with feed push-wire,including the distance between nozzle and workpiece,wire feed cables of torch,using same size tip with wire,correct usage of soft wire feed tube,bending angle of gooseneck ,installation and uninstallation of gooseneck and inner soft wire feed tube.

对推丝式半自动CO2气体保护焊焊枪的使用与维护进行了详细的叙述，包括：喷嘴至工件间的距离大小，焊枪的送丝电缆，使用与焊丝尺寸一致的导电嘴，送丝软管的正确使用，鹅颈的旋转角度、装卸方法以及内送丝软管的装卸方法等。

Breath, muscle contraction of the buttocks; arch body, as far as possible to hold his head, right leg straight towards the ceiling (peg-leg knee in order to avoid muscle tension).

呼气，收缩臀部肌肉；拱起身体，尽量抬起头来，右腿伸直朝向天花板（膝微屈，以避免肌肉紧张）。

The cost of moving grain food products was unchanged from May, but year over year are up 8%.

粮食产品的运输费用与5月份相比没有变化，但却比去年同期高8％。