排序方式: 共有81条查询结果,搜索用时 46 毫秒
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针对船舶大型化开发的3种新型岸桥 总被引:1,自引:0,他引:1
为适应集装箱船舶的大型化,ZPMC 设计制造了可以大幅度提高装卸效率的双40 ft 箱岸桥、双小车 岸桥和双40 ft 箱双小车岸桥。本文介绍这3种新型岸桥的构造和技术特点。 相似文献
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马建伟 《石家庄铁道学院学报》2010,23(1):107-110
铁路客运专线子牙新河特大桥,由于河流常年有流水,为了保障地方水系的通畅,施工的支架体系需要跨越河流,满堂支架无法满足要求,所以采用桩基础(条形基础)、钢管立柱、砂箱、分配梁、贝雷梁、模板分配梁等组成的支架体系跨越河流进行现浇施工,对现浇支架的设计、检算和施工技术进行了总结,为今后类似工程提供参考。 相似文献
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The objective of this paper is to compare vertical and horizontal cooperation among freight forwarders. The paper analyses three freight forwarders (‘players’) with two different means of transportation. The first two players are truck-operating freight forwarders. The third player is a freight forwarder with its own ship. For the purposes of analysis, the paper applied a two-stage game. The results revealed that the best form of cooperation is the one in which the large truck-operating company would establish a coalition with the ship-operating company; that is, vertical cooperation. This cooperation would generate better payoffs in the form of profit, not only to the members of this coalition, but also to the player that has not joined the coalition. However, user surplus is negative in all coalitions, which shows that the establishment of these kinds of cooperation is not beneficial (in terms of prices) for the users of these service providers. 相似文献
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高速铁路40 m跨度预制后张法预应力混凝土简支箱梁首次在我国郑济高速铁路郑州至濮阳段黄河特大桥北岸引桥进行工程应用。为了验证其预制工艺和结构受力性能是否满足规范要求,以3孔工程梁为试验对象开展了混凝土水化热测试、摩阻测试、预应力终张拉效果测试和静载弯曲试验。结果表明:试验梁水化热测试结果和浇筑工艺合格,预应力施加准确,预应力效果满足设计要求;试验梁抗裂安全性满足规范要求。3孔试验梁预制工艺和结构受力性能满足规范要求,40 m跨度简支箱梁可以推广使用。 相似文献
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喷丸处理可以使铁素体不锈钢1Cr17实现表面自身纳米化.对不同工艺的试样进行在高温空气介质中的耐氧化试验,结果表明1Cr17不锈钢经纳米化喷丸后,在氧化20 h后材料的表面可以形成一层富Cr的致密的内氧化物层,有效的防止了材料的进一步氧化.喷丸后又经过退火的试样,在氧化12 h时表面就形成了一层致密的内氧化物层,因为退火可以有效地释放因为喷丸而产生的压应力,可以更好地促进Cr向表面的扩散,更快的在合金表面形成富Cr的氧化物,从而显著提高了合金的抗高温氧化性. 相似文献
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A. F. Beckenham 《运输评论》2013,33(3):267-279
The review undertaken in this paper shows how, at the beginning of 1988, nation‐states of the world allocated ministerial responsibilities for the important function of transport. A total of 118 countries are examined, compared with 111 in 1982 (Transport Reviews, Vol. 2, No. 4) and 115 in 1985 (Transport Reviews, Vol. 5. No. 1). The analysis reveals an increase in the number of ministers solely responsible for one mode of transport, and notes an increase in the number of designated ministers for tourism. The paper goes on to examine the two main duties of ministers of transport: safety and economic regulation; and of the increasing need for closer international co‐operation as new transport technology, the growing demand for travel and expanding world trade make our world ‘an even more local village’ in the decades to come. 相似文献
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针对安装中遇到的12Cr1MoV耐热钢管的焊接问题,通过对12Cr1MoV钢进行焊接性能分析,制定了合理的焊接施工工艺。实践证明:采用该工艺进行焊接,可以获得了优良的焊缝,能够保证管道的安全运行。该工艺能为类似的管道焊接提供借鉴。 相似文献
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电弧喷涂工艺参数对3Cr13涂层性能稳定性的影响 总被引:9,自引:0,他引:9
采用正交设计方法研究了电弧喷涂工艺参数对 3Cr13涂层结合强度和耐磨性的影响。试验结果表明 :影响涂层性能稳定性的工艺参数主要是电弧电流 ,其次是喷涂距离。按涂层结合强度和按磨损失重确定的空气压力与电弧电压两个因素的主次排列顺序不同。当电弧电流一定时 ,喷涂距离过大或过小都不利于涂层性能的稳定性 ,且喷涂距离和空气压力为反向组合时涂层性能稳定性最差。涂层中的孔隙率和氧化物的数量是造成涂层性能变化波动的主要原因 ,采用较大的电弧电流可减少涂层中的孔隙率和氧化物数量 ,有利于涂层的致密性增强 ,涂层强度高 ,耐磨性也好。 相似文献