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991.
分析了甲基叔丁基醚装车系统存在的隐患,采取了规范储罐与装车点的安全距离、增设装车操作平台、配备消静电器及鹤管液下装车等措施,保证了装车的安全性。  相似文献   
992.
储油罐防腐涂料选用及施工   总被引:1,自引:0,他引:1  
储油罐内壁选用导静电涂料,油罐外壁涂料需要较长的防腐年限,所以应选用防锈性好的底漆、面漆.施工过程中应按照规定严格执行涂料施工方法,并经检测达到合格要求,才能保证质量和安全.  相似文献   
993.
    
The wastewater discharge from the process of chrome plating, which contains 6:2 chlorinated polyfluorinated ether sulfonate(F-53B) and chromium (Cr), may be toxic to biofilm.In this study we found that the biofilm formed by Pseudomonas aeruginosa PAO1 was inhibited by exposure to a combination of F-53B and Cr(VI). The combined pollution damaged the cell membranes and the structure of the biofilm, and inhibited the production of the Pseudomonas quinolone-based signal, which affected biofilm forma...  相似文献   
994.
城市灰尘是分散于城市不同区域的表面固体颗粒物。城市灰尘对城市环境造成的污染越来越多地受到人们的关注,尤其是城市灰尘重金属对城市生存环境造成的危害。本文利用R软件中的Gstat包,对金华市城市地表灰尘中的Pb元素含量进行500次条件高斯模拟,并从中随机抽出3次模拟对其模拟结果进行分析,从模拟结果可以看出研究区Pb元素总体上显示出相似的空间变化趋势,但在细部空间变化上是有差别的。条件高斯模拟法对未知点的模拟值具有不确定性,克服了普通克里格法的平滑效应,能够更好地反映研究区的随机性和结构性。  相似文献   
995.
Sandy beach habitat where sea turtles nest will be affected by multiple climate change impacts. Before these impacts occur, knowledge of how nest site selection and hatching success vary with beach microhabitats is needed to inform managers on how to protect suitable habitats and prepare for scientifically valid mitigation measures at beaches around the world. At a highly successful green turtle (Chelonia mydas) rookery at Akumal, Quintana Roo, Mexico, we measured microhabitat characteristics along the beach crawl (rejected sites) and related nest site conditions (selected sites) to subsequent hatching success rates for 64 nesting events. To our knowledge, this is the first study to report environmental data along the nesting crawl for a green turtle population and the first to use natural breaks in the data to describe their preferred habitat ranges. Our results indicate that turtles were likely using a combination of cues to find nest sites, mainly higher elevations and lower sand surface temperatures (Kruskal-Wallis test, H?=?19.84, p?<?0.001; H?=?10.78, p?<?0.001). Hatching success was significantly and negatively correlated to sand temperature at cloaca depth (Spearman’s ρ?=??0.27, p?=?0.04). Indeed, the preferred range for cloaca sand temperatures at the nest site (26.3–27.5 °C) had significantly higher hatching success rates compared to the highest temperature range (Tukey HSD?=?0.47, p?=?0.05). Sand temperatures at various depths were intercorrelated, and surface and cloaca depth sand temperatures were correlated to air temperature (ρ?=?0.70, p?=?0.00; ρ?=?0.26, p?=?0.04). Therefore, rising air temperatures could alter sand temperature cues for suitable nest sites, preferred nest site ranges, and produce uneven sex ratios or lethal incubating temperatures. Elevation cues and preferred ranges (1.4–2.5 m) may also be affected by sea level rise, risking inundation of nests.  相似文献   
996.
本文研究了不同吸水倍率的高分子吸水树脂的相变温度、相变潜热及作为蓄冷材料在35℃环境下的相变时间,并与冰做了对比。结果显示:吸收不同倍率水的高分子树脂。相变温度和相变潜热基本与水相似,随着吸水倍率的增加,相变潜热越接近于水的潜热;在相同条件下放置于隔冷袋中的高分子吸水树脂.在35℃高温环境中,可以维持20℃以下低温5h,比冰多了将近1h,克服了渗漏的缺点,在蓄冷领域表现出了明显的优势。  相似文献   
997.
    
The spatial distribution information of clay layer occurrence depth (CLOD), particularly the spatial distribution maps of occurrence of clay layers at depths less than a certain threshold, in alluvial soils is crucial to designing appropriate plans and measures for precision agriculture and environmental management in alluvial plains. Markov chain geostatistics (MCG), which was proposed recently for simulating categorical spatial variables, can objectively decrease spatial uncertainty and consequently increase prediction accuracy in simulated results by using nonlinear estimators and incorporating various interclass relationships. In this paper, a MCG method was suggested to simulate the CLOD in a meso‐scale alluvial soil area by encoding the continuous variable with several threshold values into binary variables (for single thresholds) or a multi‐class variable (for all thresholds being considered together). Related optimal prediction maps, realization maps, and occurrence probability maps for all of these indicator‐coded variables were generated. The simulated results displayed the spatial distribution characteristics of CLOD within different soil depths in the study area, which are not only helpful to understanding the spatial heterogeneity of clay layers in alluvial soils but also providing valuable quantitative information for precision agricultural management and environmental study. The study indicated that MCG could be a powerful method for simulating discretized continuous spatial variables. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
998.
    
Naturally complete mixing promotes the spontaneous redistribution of dissolved oxygen(DO), representing an ideal state for maintaining good water quality, and conducive to the biomineralization of organic matter. Water lifting aerators(WLAs) can extend the periods of complete mixing and increase the initial mixing temperature. To evaluate the influence of artificial-induced continuously mixing on dissolved organic matter(DOM) removal performance, the variations of DOM concentrations, optical cha...  相似文献   
999.
    
An indirect CO2 mineral sequestration involving two separated steps with acetic acid as a recycling medium provides a promising method for CO2 sequestration as well as the minimum CO2 emission for calcium carbonate production. In such an indirect route, the calcium carbonate production in the second gas‐liquid reactive crystallization step has been challenged by low carbonation efficiency. This paper describes significant enhancement of the second step by coupling reactive crystallization and solvent extraction with the introduction of the organic solvent, tributyl phosphate (TBP), to the process. Based on the reaction mechanism of this enhanced carbonation process, many influencing factors including stirring speed, phase ratio, reaction time, reaction temperature, CO2 partial pressure, and the composition of the initial aqueous solution, were studied. Given the operating conditions of 60 min reaction time, 500 rpm stirring speed, organic‐to‐aqueous phase volume ratio of 1, 80 °C reaction temperature, 4.0 MPa CO2 partial pressure, and initial pH of 7, the obtained crystallization conversion in the second step was found to increase from 20% to above 50%, with the incorporation of TBP and the addition of magnesium acetate.  相似文献   
1000.
安全检查是安全生产管理工作中的一项重要内容,是发现不安全状态和不安全行为的有效途径,是保持安全环境、矫正不安全行为、消除事故隐患、防止事故的一种重要措施。安全检查效果的好坏,直接影响着安全生产。笔者结合工作实际,就如何强化安全检查效果谈几点粗浅看法。  相似文献   
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