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对电磁超声换能器法的发展历史沿革进行了回顾;在理论上对(?)值估算公式的推导过程进行了完善;最后指出了该技术目前所存在的问题。 相似文献
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本文对“ITD”时域识别法做了研究,修正了前人的采样定理,提出了一种新的模态检验方法,并进行了计算机模拟验证,最后,用该方法对某厂二炼钢厂连铸机振动机构进行了识别。 相似文献
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Benzoic acid residue is solid waste produced from the production of benzoic acid by oxidizing toluene. Because it contained important chemical raw materials such as benzoic acid, benzyl benzoate and fluorenone, it is necessary to recover them from the residue. In this work the technique featured with high efficiency evaporation and vacuum distillation was developed to obtain total recovery and utilization of the benzoic acid residue. By controlling the operation temperature at 260°C and the pressure of 16 kPa in the rising and falling film evaporators, heavy components separated efficiently from the residue can be polymerized and the light components consisting of 63% of the residue entered into a benzoic acid vacuum distillation column. Keeping the temperature of polymerization at (280±10)°C, coumarone resin was produced after adjusting the softening point according to the market re-quirements. Vacuum distillation was operated under the following conditions: top temperature at 186°C, top pres-sure of 16 kPa, bottom temperature at 240-250°C, reflux ratio being 3︰1. Benzoic acid of 98% purity was distilled out from the column as a side stream and the bottom product was crude benzyl benzoate. By the developed tech-nique, the benzoic acid residue was splitted into three products, benzoic acid, crude benzyl benzoate and coumarone resin without any surplus waste. 相似文献
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利用平衡态分析和Ti-IF钢析出物形成元素含量波动对高温二相粒子的析出规律进行了研究,得到了析出物开始析出时各个析出物形成元素含量的临界值,对MnS析出条件有新了认识,并给出了Mn加入后所造成的各析出物元素重组关系示意图 相似文献
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r值是评价深冲钢板成型性能的重要指标之一。r值的在线无损连续检测对沿整个板卷长度方向实行质量监控极为有益。通过对目前的X射线法和电磁超声法r值在线检测技术各自特点的讨论,提出了电磁超声法更具发展前途的结论。 相似文献