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1.
本文通过对两级伸缩式液压缸与四柱滑轨结合使用中所出现问题及处理过程的阐述,提出了在液压系统设计与制造中,准确的原理仅仅是基础,其上还有许许多多的细枝末节需要仔细修剪,比如污染、噪声、温度、泄漏以及与机械的协调等等。 相似文献
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对污染源废气监测原理进行了简单分析,阐述了当前我国常用的环境中污染源废气检测方法,并对废气检测影响因素及质量控制进行了深入探究。 相似文献
3.
压裂是油层改造、新井投产、老井稳产、单井产能提高的重要手段,然而压裂增产的同时,也会不可避免地给油层带来较为严重的伤害,导致压裂无效或减产,不能达到预期的增产效果,为此试验应用了压裂后污染处理技术。该技术由HY-25、HY-26、HY-27三种成分组成,可有效缩短排液周期,改善破胶液返排效果,对支撑剂质量不产生明显影响。现场实施后效果非常好,产液量增加,含水率大幅度下降。低渗透油田压裂后污染处理技术针对性强,综合性强,采用多段塞配合的新工艺,施工工艺简单,成功率高,低伤害,低成本,施工安全,处理效果显著。 相似文献
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飞机液压系统污染及控制 总被引:2,自引:2,他引:0
本文全面分析了收音机液压系统污染的危害和主要原因,并在此基础上有针对性地提出了预防措施。 相似文献
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Permeable reactive barrier for groundwater remediation 总被引:4,自引:0,他引:4
R. Thiruvenkatachari S. Vigneswaran R. Naidu 《Journal of Industrial and Engineering Chemistry》2008,14(2):145-156
This article aims to provide an overview of the upcoming technology of permeable reactive barriers for groundwater remediation. A comprehensive list of references and web-links are also provided for further in-depth understanding. A brief discussion on the Australian perspective on this emerging technology is also included. 相似文献
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The price of SO2 permits and the volume of trading under the US Acid Rain Program have been lower than expected. This can be explained by the creation and distribution of more permits than were initially authorized, by the sale of permits by high cost abaters who are subject to more stringent local emission constraints or who have irreversibly invested in high cost abatement technologies and by the deregulation of the natural gas and railroad industries which, in combination with incentives for cost-cutting under the new market approach to SO2 control, has lowered marginal costs of abatement curves and made them more uniform across powerplants. The low price of permits and low trading volume are evidence that market approaches to pollution control can be more cost-effective than command and control regulations. The effect of public policies and technological changes on the allowance market are usefully examined in the context of an ideal market, in which the equilibrium price of allowances equals the marginal cost of abatement of individual powerplants. Using recent data from Coggins and Swinton (1996), we are able to explain the current price of permits with some accuracy. 相似文献
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文章回顾了石化合成洗剂的发展历史,从经历的五代产品的发展过程中可以看出它经历了一个环保到不环保再到环保的曲折过程分析了石化合成洗剂的主要成分及其清洗去污的作用原理着重指出目前使用的石化合成洗剂虽然给生活带来便利,但同时也给人体健康和生态环境都造成严重的危害;倡导使用新型环保型的第五代洗剂已成为新世纪中清洗剂发展的必然趋势。 相似文献
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S. Bari J. Naser 《Tunnelling and Underground Space Technology incorporating Trenchless Technology Research》2005,20(3):490
Detailed analyses of smoke movement from a burning vehicle in a road tunnel have been carried out for the westbound Melbourne City Link tunnel. The time-averaged equations for velocity, pressure, temperature, and mass fraction of emissions were solved for transient condition using the CFD software FLUENT 6.0. For the analysis, a burning bus was assumed to release an equivalent energy of burning 500 l of diesel in 6 min, with vehicles upstream of the fire at a standstill. On the other hand, the vehicles downstream of the fire had enough time to escape from the tunnel through the exit portal. Due to the action of jet fans, most of the smoke was pushed downstream of the fire. The smoke had also dispersed about 55 m upstream of the fire, putting the passengers in this region at great risk. The emissions released from the vehicles in the jam, with their engines running, also posed a threat to human health. Within 8 min after the fire had started, the mass concentrations of O2, CO2 and CO were in the ranges of 0.12–0.15, 0.08–0.11 and 0.0006–0.0014, respectively. Therefore, quick evacuation of the passengers is essential in the event of a fire in the tunnel. 相似文献