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61.
肖作声 《筑路机械与施工机械化》1993,10(3):18-24
渣油燃烧技术已在沥青混凝土设备中逐步得到应用,本文分析了燃烧渣油的两种技术途径,重点介绍了燃油掺水乳化新方法的优点、燃烧机理和应用中需要考虑的几个问题,结合实例,说明了燃油掺水乳化技术在沥青混凝土设备中的使用方法和明显的节能效果。 相似文献
62.
利用浮动法和落砂法研究了酸枣仁油剂对小鼠自主活动的影响,结果表明酸枣仁油乳剂在1.4ml/kg或0.35ml/kg灌胃给药,每天2次,连续3d,可使小鼠自主活动减少;酸枣仁油乳剂与戊巴比妥钠合用,可协同延长小鼠的睡眠时间。提示酸枣仁油可能是酸枣仁镇静催眠作用的有效成份。 相似文献
63.
Juan Santos-Echeandía Ricardo Prego Antonio Cobelo-García 《Journal of Marine Systems》2008,72(1-4):350
The water column above the Prestige wreckage was sampled during two consecutive campaigns: Prestinaut (December 2002) two weeks after the tanker sunk and HidroPrestige0303 (March 2003) one month after the sealing of the main fuel leaks. Samples of the original cargo fuel and the emulsified fuel in the surface of the ocean were also collected. Analysis of the fuel indicated the release of 135 kg of Cu, 1700 kg of Ni and 5300 kg of V from the original fuel to the water column, remaining 35 kg of Cu, 3100 kg of Ni and 13,800 kg of V in the emulsified fuel. The metal partitioning between the water column and the emulsioned floating fuel, Cu > Ni ~ V, are in accordance with the stability index for the metal–nitrogen bond in metalloporphyrins. This release had an impact on dissolved trace metal concentrations in the water column. An increase on dissolved copper (2.8–4.7 nM) and nickel (2.2–8.0 nM) with respect to natural values (1–3 nM for Cu and 1.6–5 nM for Ni) was observed. Values for vanadium (28–35 nM) were in the range of pristine North Atlantic waters (30–36 nM). This contamination was especially observed in the upper water column (0–50 m), associated with the mixing of seawater with the fuel moving upwards, and in deep waters, where the residence time of fuel is higher. Future research in this field should focus on the environmental variables and the processes that control the release of contaminants from fuels for a better assessment of the contamination in oil-spill events. 相似文献
64.
陈建光 《南通航运职业技术学院学报》2014,(2):51-55
文章针对GRAVINER Mark6 OMD调试和维护管理困难等问题,分析其系统结构、新技术特点,并提出了管理与维护方法及失效时导致曲轴箱爆炸事故处理办法,对船舶机电调试及管理工作有一定的参考意义。 相似文献
65.
66.
Transformation of the motor vehicle fleet has been an important feature of the world’s peak car phenomenon. Very few urban transport studies have explored such important changes in large urban cities. Using an innovative green vehicle datasets constructed for 2009 and 2014, this paper investigates the ongoing change in urban private vehicle fleet efficiency (VFE) in Brisbane. The spatial patterns of VFE change were examined with social-spatial characteristics of the urban area. The results showed that the social and spatial effect of VFE changes remain uneven over urban space. The inner urban areas have experienced higher level of VFE change, whilst people in the outer and oil vulnerable areas showed a low tendency in shifting to more efficient vehicles. The implication of VFE change for future household vehicle adoption was also evaluated based on a cost-benefit analysis of new vehicle technology costs and expected fuel savings for households that choose a fuel efficient vehicle. The results show that imposing a stronger national fuel economy target in the long term would accelerate evolution of vehicle fleets and oil vulnerability reduction in Brisbane. 相似文献
67.
Manuel Gonzlez Luis Ferrer Adolfo Uriarte Agurtzane Urtizberea Ainhoa Caballero 《Journal of Marine Systems》2008,72(1-4):178
This contribution describes the procedure used during the Prestige oil-spillage event, by means of an Operational Oceanography System, and the behaviour of the present prediction tools (hydrodynamic and dispersion models) applied to it. The accuracy of these tools is estimated by a reanalysis of field data transmitted by a sea surface drifting buoy, released at the time of the oil spill. The numerical models applied were the Regional Ocean Modeling System (ROMS), fed by the available six-hourly NCEP atmospheric information, together with a Lagrangian Particle-Tracking Model (LPTM). ROMS has been used to estimate the current fields for the Bay of Biscay, whilst the LPTM has provided the oil spill trajectories. The results demonstrate that the accuracy of the numerical models depends upon the quality of the meteorological input data. In this case, the current fields at the sea surface, derived by ROMS, have been underestimated by the wind fields of the NCEP reanalysis data. An efficient calibration of these wind fields, with data provided by the Gascony buoy (fixed oceanic and atmospheric station), achieves more realistic looking results; this is reflected in the comparison between the buoy trajectory predicted numerically and the tracked movements of the drifting buoy. 相似文献
68.
对于自动变速器油泵,可通过失速试验和时间滞后试验来检查油泵的性能和判断油泵有无故障。经分析认为,主动齿轮、齿环与泵壳凸台配合间隙超限,主动齿轮、齿环与泵壳接触面磨损量超限,以及O形圈老化或断裂是造成油泵性能下降的主要原因。 相似文献
69.
油封是汽车发动机,变速器,分动器和驱动桥等总成中的重要密封年。阐述了汽车用油封的密封机理,结构形式及各参数之间的关系,介绍了动力型油封的结构特点和性能特点,并对比分析了目前普遍用于制造油的4种合成橡胶材料的优,缺点,开发低摩擦油封是一个发展方向,论述了降低油封摩擦转矩的途径。 相似文献
70.
液压油污染是引发筑养机械液压系统故障的主要原因,通过对液压油性能及污染程度的现场分析,给出了防止液压油污染的控制标准和措施。 相似文献