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11.
葛明军 《探矿工程》2007,34(11):43-45
钻井液固相控制是欠平衡钻井成败的关键技术之一。乳化钻井液的配制、监控、维护直接影响油气的发现。结合SN308钻井施工,从地层负压值的设计,以及钻井液密度、水压力的计算,确定了乳化柴油钻井液的各项性能指标,并提出了使用和维护管理方法,在施工中得到成功的应用。  相似文献   
12.
Outdoor smog chamber experiments were performed to investigate gas/particle (G/P) partitioning behavior of aldehyde compounds in atmospheric acidic aerosols. Diesel soot and wood smoke aerosols were selected as acidic aerosols and octanal, decanal, undecanal, and cis-pinonaldehyde for aldehydes compounds. Aerosol acidity was measured with the equivalent sulfuric acid amounts in aerosol mass: 0.2–0.6 wt% in diesel soot and 0.04–0.1 wt% in wood smoke aerosols. Experimentally determined partitioning coefficients of aldehyde along with other classes of semivolatile organic compounds (SOCs) were compared with the estimation. All experimental G/P partitioning coefficients of aldehyde compounds were 10–200 times higher than estimated partitioning coefficients. Aldehyde partitioning coefficients in wood soot were similar or less than diesel soot aerosols.  相似文献   
13.
为进一步研究地下水曝气原位修复技术的影响因素,采用室内实验的方法系统地研究了含水介质对原位曝气技术修复地下水污染的影响。研究结果表明:大量水相中的柴油在曝气的开始阶段被去除,随着时间的延长,污染物去除率不断增加,但增加的幅度逐渐减小。污染物去除率与时间关系曲线符合对数曲线规律,相关方程为y=alnx+b,R2=0.802 4~0.907 1,相关性较好。含水介质的渗透系数对地下水污染修复的影响较大,渗透系数与污染物的去除率基本呈正相关关系,渗透系数越大,污染物的去除率越大;含水介质密度与污染物去除率基本呈负相关关系,含水介质密度越大,污染物的去除率越小。  相似文献   
14.
目前在压实黏土层(CCL)应用于油类污染物的防渗工程设计中,以水在CCL中的渗透系数低于10-7 cm/s为依据,该依据可能存在偏颇。文中以0#柴油和93#汽油作为典型油类污染物,在云南CCL中进行油相水相交替渗流实验。结果表明:(1)不同渗透压力下,水在云南CCL中的渗透系数为(0.41~2.52)×10-8 cm/s,云南黏土压实后可作为天然防渗衬层。(2)0#柴油和93#汽油穿透饱水的云南CCL时,存在临界水力梯度,分别为0.05和0.02 MPa;一旦突破临界水力梯度,CCL的渗透性急剧增大,0#柴油和93#汽油在CCL中的渗透系数较水在CCL中的高出1~3个数量级。(3)水相驱替0#柴油和93#汽油的过程中,CCL的渗透系数为10-7~10-6 cm/s;被油浸透过的CCL不能继续作为防渗衬层使用。(4)针对油类污染物的CCL防渗工程设计,以水在CCL中的渗透系数低于1.0×10-7 cm/s为标准是不适用的,需要提高CCL防渗的设计等级。  相似文献   
15.
Summary Results of a performance study of diesel ram-dump cars and electric cable-reel shuttle cars, conducted at an underground coal mine in the Warrior Basin of Alabama, are presented. Time-study data, obtained over a one-year period, show that the average load and discharge times of the diesel cars are slightly less than those of the electric cars, while the average travel-loaded, travel-empty, in, and out speeds of the diesel cars are slightly greater.Computer simulations, based on frequency distributions from the cycle-time data, show average shift productions for both vehicle types to be very close for two-car and three-car configurations with a haul distance of two crosscuts. However, as the haul distance increases, the diesel cars outproduce the electric cars.Results of a maintenance-cost comparison are presented for the sake of general interest and should not be considered as valid comparison, since the electric cars are approximately three years older than the diesel cars. The results show preventive maintenance costs to be much greater for a diesel car on both permonth and per-ton bases, and the total maintenance cost for a diesel car to be significantly higher on a permonth basis, but significantly less on a per-ton basis.  相似文献   
16.
Clean sediment collected from O'Brien Bay, East Antarctica, was artificially contaminated with a mix of Special Antarctic Blend diesel fuel and lubricating oil and deployed in two uncontaminated locations (O'Brien and Sparkes Bays) and a previously contaminated bay (Brown Bay) to evaluate whether a history of prior contamination would influence the biodegradation process. Detailed analysis of the hydrocarbon composition in the sediment after 11 weeks revealed different patterns of degradation in each bay. Biodegradation indices showed that hydrocarbon biodegradation occurred in all three bays but was most extensive in Brown Bay. This study shows that even within a relatively small geographical area, the longevity of hydrocarbons in Antarctic marine sediments can be variable. Our results are consistent with faster natural attenuation of spilt oil at sites with previous exposure to oil but further work is needed to confirm this. Such information would be useful when evaluating the true risk and longevity of oils spills.  相似文献   
17.
With the increasing researches on geotechnical properties of the diesel contaminated soil ( DCS), the water content measured is indispensable part during the early period. In this study, the relative error of water content measurement using the traditional method is as high as 20.78%, which is no longer suitable for contaminated soil. Through a series of tests to measure the loss coefficient of diesel in the drying time, the authors finally proposed a modified calculation formula for test samples. The results show that the maximum relative error calculated by using the modified formula is 0.96% , far lower than that of traditional formula, which can pro- vide accurate data for further study of diesel contaminated soil.  相似文献   
18.
本文论述了不同浓度的沙柴油污染海洋底栖围隔生态系后,在各相中的分布及其变化。实验结果表明:柴油添加后20h,底质油含量与水体油污染含量成正相关;菲律宾蛤行(Ruditapesphilippinarum)对柴油有较强的富集能力。柴油中短链正构烷烃(C8~C15)较易消失。柴油对底栖生态系的影响周期较长。  相似文献   
19.
轻柴油/海水微乳[状液]形成的相图研究   总被引:1,自引:0,他引:1  
用相图方法研究轻柴油/海水微乳的形成。体系相图由水或人工海水(盐度分别为S=0,10,115,29.471和41.071)/柴油/表面活性剂(AS、CTAB或BRIJ35)/助表面活性剂(正丁醇)在40℃时构成。本文分别研究了表面活性剂类型,油、醇、表面活性剂三者配比及海水盐度对微乳形成的影响。研究结果表明:三种表面活性剂中CATB,酸与表面活性剂的重量比值大于0.43,含油量≤25%,最适宜于形成微乳;形成微乳区面积分数随柴油含量增加而减少,也随海水盐度增加而减少,微乳区总面积分数随海水盐度变化率CTAB>AS>BRIJ35,三种表面活性剂体系的微乳区总面积分数依次为CTAB>AS>BRIJ35;在含紫油量>50%时,三体系主要形成的W/O微乳区,在柴油含量≤25%时,对于CTAB体系可形成O/W至W/O连续变化微乳区,对于AS体系,可形成W/O和O/W两个独立的微乳区,而对于BRIJ35体系只形成W/O微乳区。  相似文献   
20.
刘广志 《探矿工程》2004,31(1):7-10
为适应广大科技工作者了解国外新能源的发展态势,从而关注我国新能源发展前景,集中编辑了有关生物质能、生物柴油、太阳能、风能、地热、氢能等多种新能源的国内外发展态势,分析了各自的开发利用潜力和前景,以供大家借鉴,有利于开展某些项目的研发。相信不久的将来,我国新能源事业,能尽快走上“快车道”、“高速路”。  相似文献   
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