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概述了山西省中部引黄工程输水工程总干线2号隧洞情况,从地质情况与设计过程两方面介绍了总干2号隧洞穿越忻保高速公路改线段设计情况,通过对其进行综合优化必选设计,可有效保证忻保高速公路的正常运营。 相似文献
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Ca,Y对AZ91镁合金显微组织和力学性能的影响 总被引:7,自引:0,他引:7
向AZ91镁合金中加入具有阻燃作用的合金元素Ca和Y,研究了单独加入Ca和同时加入Ca,Y对AZ91合金铸态显微组织和力学性能的影响。结果表明:向AZ91合金中单独加入Ca可使该合金的铸态组织明显细化,当Ca含量大于1ω%时,合金铸态组织中生成了Al2Ca新相,使该合金的抗拉强度得到提高。在此基础上加入少量的Y(0.10%-0.50%)(质量分数,下同)可使合金的铸态组织进一步细化,该合金的抗拉强度随Y含最的增加先提高后降低。 相似文献
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为了南水北调石方渠道K204+482—K204+982段的施工安全,需要进行石方渠道爆破方案设计,介绍了该工程的施工概况,通过对手风钻钻孔爆破与潜孔钻钻孔控制爆破两种方案的施工方法、工期进度、安全防护、资金投入及利弊分析等进行综合对比,确定采用潜孔钻控制爆破方案进行施工。 相似文献
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Effect of Ca and Y additions on oxidation behavior of AZ91 alloy at elevated temperatures 总被引:1,自引:0,他引:1
In order to develop the ignition-proof magnesium alloy, the effect of alloying elements, Ca and Y, on the oxidation behavior of AZ91 magnesium alloy at elevated temperatures was investigated. The ignition-proof performance, oxide products and oxidation kinetics of Ca- and Y-containing AZ91 alloys were studied. The results indicate that the proper addition of Ca can increase the ignition point of AZ91 alloy greatly. However, the oxide film of Ca-bearing AZ91 alloy formed at elevated temperature is thick and brittle, which is prone to crack in melting and cooling process. In addition, the oxide film of AZ91-xCa alloy is incompact and cannot inhibit the diffusion of reaction particles. The oxide film of AZ91-xCa alloy turns to thin and plastic one after Y is added, and the density of the oxide film increases greatly due to the formation of composite oxide film composed of MgO, CaO and Y2O3. 相似文献
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灵石中部引黄县域小水网供水工程,以山西省大水网中部引黄工程为依托,每年向灵石县供水2 160万m3,全部为工业供水,供水保证率为P=95%。本项目根据地质勘查成果资料和1∶2 000实测地形平面图布置设计,通过对工程概况分析、项目的选址、线路的选择以及受水点的确定等方面进行总体布设,达到优化合理设计方案,为项目的实施提供了科学依据。 相似文献
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