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991.
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
992.
以京广线孟庙至长台关段为例,介绍在保持既有线正常运营的前提下,采用纵断面调整、路基换填、水泥土挤密桩等工程措施对既有路基进行加固,使其满足200km/h的提速要求。 相似文献
993.
J. Venkatesan G. Nagarajan R. V. Seeniraj R. Murugan 《International Journal of Automotive Technology》2010,11(3):317-322
Mathematical simulation is the process of designing a model of a real system and then conducting experiments with the simulation
to understand the system’s behavior. Mathematical simulation is widely used for investigating and designing compressors, and
with a minimal number of simplifying assumptions, mathematical models can be used in conjunction with modern computing tools
to solve complicated problems. A considerable amount of previous research has focused on the mathematical modeling of reciprocating
air compressors used in automotive braking. The aim of the present work was to experimentally validate the mathematical model
for such compressors. We present a simplified and effective mathematical model for estimating compressor performance, and
this model can easily be executed using personal computers. Parameters such as compressor speed, discharge pressure and clearance
volume were evaluated in terms of their effect on the thermodynamic behavior of compressors. The model can predict cylinder
pressure, cylinder volume, cylinder temperature, valve lift and resultant torque at different crank angles; it can also predict
the free air delivered and the indicated power of the compressor. Therefore, the model has been validated using experimental
results. 相似文献
994.
T. Ciobotaru D. Frunzeti L. Jäntschi 《International Journal of Automotive Technology》2010,11(2):167-172
This paper presents a method for analyzing epicyclic gearboxes by evaluating the speeds, torques and power of the external
elements in epicyclic gear mechanisms, as well as the total ratios of the gear box. The method is based on the equations that
describe each epicyclic gear mechanism and rules that assign appropriate codes to the external elements. The method emphasizes
how power flows are transmitted through the epicyclic gears, as well as power losses. Analysis of an epicyclic gear box is
performed to illustrate the proposed method. 相似文献
995.
996.
M. Hatzopoulou E.J. Miller 《Transportation Research Part D: Transport and Environment》2010,15(6):315-325
This paper describes the development of an integrated approach for assessing ambient air quality and population exposure as a result of road passenger transportation in large urban areas. A microsimulation activity-based travel demand model for the Greater Toronto Area – the Travel Activity Scheduler for Household Agents – is extended with capabilities for modelling and mapping of traffic emissions and atmospheric dispersion. Hourly link-based emissions and zone-based soak emissions were estimated. In addition, hourly roadway emissions were dispersed at a high spatial resolution and the resulting ambient air concentrations were linked with individual time-activity patterns derived from the model to assess person-level daily exposure. The method results in an explicit representation of the temporal and spatial variation in emissions, ambient air quality, and population exposure. 相似文献
997.
韩秀梅 《内蒙古公路与运输》2003,(3):38-39
针对内蒙古锡林郭勒盟省际通道公路工程建设的实际.为保护环境.减少对草场和农田的破坏,采用了开采石质填料填筑路堤的方法。文章对填石路堤的施工、压实标准、检测方法及质量控制方面进行了探讨。 相似文献
998.
The past quarter of a century has brought with it significant change in the field of port management, both in terms of the goals that are set and the tools used. This trend has resulted in increased pressure on port authorities. The purpose of this paper is to deal in greater detail with developments in this area of port economics. 相似文献
999.
1000.