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铁路喷漆作业混苯治理措施的研究 总被引:1,自引:0,他引:1
铁路喷漆作业现场及喷漆作业过程中散发在空气中的有机废气[挥发的溶剂(酯、酮、醇类)及稀释剂(煤焦油类、苯、甲苯、二甲苯)]及固体漆雾粒子(树脂、颜染料)。依据国内外各行业喷漆技术发展的动向,找到了解决铁路机务段、车辆段及铁路工厂喷漆作业混苯物污染的控制手段。即:改革工艺采用新技术和新材料,实施上送风下排风空气幕及实施净化措施和加强个体防护的综合治理措施。 相似文献
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The climate change has made the transit through Arctic area more feasible, which demands reliable methods to evaluate ship performance. Ship performance in ice is a cross-scale problem, where the desired output such as ship speed lies in larger scale while the actual ship-ice interaction happens in smaller scale. Due to insufficient knowledge in ice mechanics and the demand for computational efficiency, existing approaches for modelling ship-ice interaction from ship performance perspective are mostly either (semi-) empirical, or simplified analytical, with reduced dimensions and extensively simplified mechanics. This paper presents a novel approach to model ship-ice interaction, which maintains the accuracy of the modelling with Finite Element Method (FEM) in ship-ice interaction scale, while being computationally very cheap, therefore is capable to be applied in ship scale simulations. The ice failure is firstly qualitatively investigated through full-scale and model-scale observations, as well as a numerical simulation with Extended Finite Element Method (XFEM). The model is then simplified and executed by Abaqus to automatically run a large database. A neural network is used to fit the results to get a simulation-free tool for ship-ice interaction calculation. Finally, the uncertainty in the results due to an important assumption is quantified. The results show that the obtained neural network fits the database with excellent performance. Therefore, it can be applied in ship scale simulations with improved accuracy compared to empirical or analytical approaches. 相似文献
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The ice resistance on ships in escort operations in level ice are investigated using the discrete element method (DEM). A dilated polyhedron—generated by the Minkowski sum of a sphere and a polyhedron—is employed in the DEM; this dilated polyhedron-based DEM (DPDEM) is adopted to simulate the ship–ice interaction, wherein the contact force and bond-failure criterion are considered for the collision and fracture of sea ice, respectively. A three-point bending test was simulated with DPDEM, and a field test was conducted in the Bohai Sea to validate the DEM results. Further, a parametric analysis of flexural strength was conducted to identify the parameters involved in the bond-failure criterion. The ice resistance on icebreakers and cargo ships in level ice are simulated using DPDEM. The simulated ice resistances are compared with the Lindqvist and Riska formulas and the model test, which proves the validity of the DEM simulation. The interaction between ships and level ice is simulated parametrically to investigate the ice resistance on cargo ships with and without the icebreaker escort. Influencing factors such as ship speed, ice thickness, and ship breadth were examined to investigate the ice resistance on the escorted cargo ship. Analysis and change rules of the ice resistance on cargos affected by those factors were given. 相似文献
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从改进绝缘滴烘工艺、改进绝缘结构及改进绝缘漆性能等方面,叙述绝缘处理的防漆液流失技术,对11 58漆直接高温烘焙等问题,提出看法。 相似文献
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P. J. Minnett F. Bignami E. Bhm G. Budus P. S. Galbraith P. Gudmandsen T. S. Hopkins R. G. Ingram M. A. Johnson H. J. Niebauer R. O. Ramseier W. Schneider 《Journal of Marine Systems》1997,10(1-4)
A summary of the seasonal development of the Northeast Water Polynya ice cover characteristics is presented. This is based primarily on satellite remote sensing observations, with some in situ measurements, including both new and published data. 相似文献
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桔皮鲜映性仪用于面漆的外观改善 总被引:1,自引:0,他引:1
简述桔皮鲜映性仪的基本原理,并借助桔皮鲜映性仪,对客车面漆外观进行改善。 相似文献