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本文介绍了一个高位水池暑期混凝土工程从原材料选择、配合比设计到运输、泵送、施工、养护的完整过程,通过对各环节的管控,使得工程质量得到了很好的保障。 相似文献
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近年来,商务白酒在市场上做得风生水起,大有改写白酒市场产品格局的趋势。为迎接这种趋势,古鹤松早有准备。 相似文献
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2006年新年伊始,我走进了济南女儿红白酒销售有限公司董事长林祥超的办公室,在办公室里,最醒目的就是挂在墙上的“社会资源整合做营销”隶书体九个大字。那么,女儿红的社会资源整合策略,都包含着哪些内容呢? 相似文献
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建立了Si3N4陶瓷引弧微爆炸加工过程的传热学模型,并基于有限元理论,利用大型的高级数值仿真软件COMSOL Multiphysics对Sigq4陶瓷引弧微爆炸加工的温度场分布进行了模拟。并结合实际加工过程,对加工后冲击凹坑的宽度和深度进行了预测。仿真结果表明,Si3n4陶瓷引弧微爆炸加工在给定的加工参数下的最高温度可达到12100℃,但高温影响区范围很小;其材料的去除率随着脉冲宽度和加工电流的增加而增加,随着喷嘴半径的增加先增加后减小;径深比随着脉冲宽度和加工电流的增加而减小,随着喷嘴半径的增加而增加。实验验证了仿真结果的正确性。 相似文献
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With the continuous improvement of current levels in power systems,the demands on the breaking capacity requirements of vacuum circuit breakers are getting higher and higher.The breaking capacity of vacuum breakers is determined by cathode spots,which provide electrons and metal vapor to maintain the arc.In this paper,experiments were carried out on two kinds of transverse magnetic field (TMF) contacts in a demountable vacuum chamber,the behavior of the cathode spots was recorded by a high-speed charge-coupled device (CCD) video camera,and the characteristics of the cathode spots were analyzed through the image processing method.The phenomenon of cathode spot groups and the star-shaped pattern of the spots were both discovered in the experiment.The experimental results show that with the condition of TMF contacts the initial expansion speed of cathode spots is influenced by some parameters,such as the tested current,contact gap,the structure of the contact,the contact diameter,the number of slots,etc.In addition,the influence of the magnetic field on the formation of the cathode spot groups,the distribution,and the dynamic characteristics of the cathode spots were analyzed.It is concluded that the characteristics of the cathode spots are due to the effect of the magnetic field on the near-cathode plasma.The study of the characteristics of cathode spots in this paper would be helpful in the exploration of the physical process of vacuum arcs,and would be of guiding significance in optimizing the design of vacuum circuit breakers. 相似文献