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381.
ES-2001采油队安全生产巡检管理系统的开发与应用   总被引:3,自引:1,他引:3  
介绍了新开发的ES—2001采油队安全生产巡检管理系统的系统构成和特点及巡检工作过程。采用非接触式射频信息卡,大大方便了职工巡检刷卡,借助油田局域网可随时对基层单位的巡检结果进行网页浏览,直接看到巡检记录报表和漏检记录报表,客观公正地进行考核,提高了综合管理水平。  相似文献   
382.
Efficient monitoring systems addressing the difficulty of detecting narrow contaminant plumes originating from unknown point sources are needed for modern landfills. A low‐discharge extraction and accompanying injection wells could potentially address this problem. This hypothetical computer‐modeling study involved a three‐well detection system consisting of one extraction and two injection wells at a rectangular landfill in a shallow, unconfined aquifer. The extraction and injection wells were located near the landfill's downgradient and cross‐gradient corners, respectively. Each injection well pumped at half the rate of the extraction well. A minimum pumping rate of 1.1 cubic meters per day was determined for the three‐well system; at this rate, all contaminant plumes originating within the landfill's footprint entered the extraction well prior to reaching a downgradient property boundary. In comparison, five passive (not pumped) wells detected all contaminant releases from the landfill. Results of this study suggest that a low‐discharge extraction well with accompanying injection wells may be an effective contaminant detection strategy at some waste impoundments.  相似文献   
383.
针对超长工作面抽采时间不均衡导致抽采达标时间长的问题,提出了工作面分区增透高效抽采技术,运用分组试验和理论分析的方法,研究了不同布孔工艺参数条件下CO2相变致裂对低透煤层瓦斯抽采的增透作用规律,并在试验工作面进行了工业应用。研究结果表明:CO2相变致裂技术对低透煤层增透促抽效果良好,与未致裂抽采相比,采用间距20,10,5 m致裂孔致裂条件下进行抽采时煤层透气性系数分别提高1.8,2.6,5.8倍,平均抽采体积分数分别提高1.9,3.5,4.2倍,平均抽采纯量分别提高2.4,4.2,6.2倍。试验工作面应用分区增透高效抽采技术后,整个工作面形成后仅需抽采87 d即可达标进行回采,显著缩短了抽采周期,对高瓦斯低透煤层缓解采掘接替紧张及提高瓦斯抽采效率具有重要借鉴意义。  相似文献   
384.
韩磊  李卓  吴志根 《环境工程》2016,34(5):137-142
污泥的可生物降解性能由其有机组分的生物可及度和组分分子的复杂度共同决定。通过采用化学分级提取方法研究污泥组分的生物可及度,使用不同强度的提取溶液分离出4种化学可及度不同的提取组分,同时结合三维荧光光谱法对各组分中有机物质的复杂度进行分析。分析结果表明:组分的化学可及度与其生物可及度之间存在正相关关系;生物可及度较高,其成分有机物分子结构简单的组分SPOM(soluble particulate organic matter,SPOM)与REOM(readily extractible organic matter,REOM)在厌氧消化过程中降解率较高,分别为59.2%与46.3%的COD;而生物可及度低,组成复杂的组分SEOM(slowly extractible organic matter,SEOM)与PEOM(poorly extractible organic matter,PEOM)的生物降解率分别只有18.4%和5.8%的COD。  相似文献   
385.
采用酸浸—萃取—沉淀法回收废锂离子电池中的钴。实验结果表明:废锂离子电池在600℃下煅烧5 h可将正极材料上的有机黏结剂与正极活性物质分离;正极活性物质在Na OH溶液浓度为2.0 mol/L、n(Na OH)∶n(铝)=2.5、碱浸温度为20℃的条件下碱浸反应1 h后,铝浸出率达99.7%;已除铝的正极活性物质在硫酸浓度为2.5 mol/L、H_2O_2质量浓度为7.25 g/L、液固比为10、酸浸温度为85℃的条件下酸浸反应120 min,钴浸出率高达98.0%;酸浸液在p H为3.5、萃取剂P507与Cyanex272体积比为1∶1的条件下,经2级萃取,钴萃取率为95.5%;采用H_2SO_4溶液反萃后在硫化钠质量浓度为8 g/L、反萃液p H为4的条件下沉淀反应10 min,钴沉淀率达99.9%。  相似文献   
386.

The present study describes the application of different solid-phase extraction techniques for the extraction, separation, and quantitative determination of 10 commonly used herbicides with different chemical structures (chlorsulfuron, diuron, bentazone, linuron, chlorpropham, fenoxoprop-ethyl, MCPA, diclofop-methyl, fluazifop-butyl, trifluraline) in water. Octadecyl (C18) Empore extraction disks, octadecyl (C18), and stryene divinylbenzene (SDB) Bond Elut Env cartridges were compared for solid-phase extraction efficiency. Herbicides were separated and quantified by reversed-phase high performance liquid chromatography with diode-array detection (HPLC-DAD) with simultaneous separation on two columns of differing polarity (C18 and CN) to confirm identification. Analytical separation was performed simultaneously on C18 and CN columns. Reanalysis of the sample extracts on a (cyano) CN column were used to confirm the identity of these compounds. Method optimization and validation parameters were presented in this work. Recoveries varied from 76.0% to 99.0% for C18 disks, from 75.1% to 100.0% for C18 cartridges, and from 54.0% to 98.0% for SDB cartridges over concentrations at 0.025–0.4 μg L?1. The limits of detection were 0.012–0.035 μg L?1.  相似文献   
387.
A facile and novel method has been developed for the determination of cadmium, chromium, copper, lead, and zinc from various water samples using FAAS. In the present investigation, a syringe was loaded with sorbent (rice bran) for the separation and enrichment of cadmium, chromium, copper, lead, and zinc, prior to their analysis by flame atomic absorption spectrometry which was described to substitute the batch and column techniques. The syringe was loaded with 2.0 g of sorbent in order to retain the analyte elements. Six milliliter of sample solution (pH 8.0 ± 0.2) was drawn into the syringe in 15 s and discharged over a period of 15 s. Then, 2.0 M HCl eluent was drawn into the syringe and ejected back to desorb the analyte elements. At the optimum conditions, the percentage recoveries of Cd, Cr, Cu, Pb, and Zn was in the range of 95.5–99.4% with SD of 0.10%. The elements could be concentrated by drawing and discharging several portions of sample successively. The detailed study of various interferences made the confirmation of the method highly selective. The risk of contamination is less than that with the column technique. The method was successfully applied for the determination of Cd, Cr, Cu, Pb, and Zn in spiked and natural water samples. The results obtained are in good agreement with the reported methods at the 95% confidence level.  相似文献   
388.
Surface mining is a global phenomenon. When dealing with the land disturbances caused by surface mining operations, the terms remediation, reclamation, restoration and rehabilitation (R4) are commonly used interchangeably or otherwise vaguely defined. Expectations associated with these terms may differ significantly from one stakeholder to another, however. Regulators, industry, environmental practitioners, local communities and the general public therefore stand to benefit from a precise terminology based on agreed-upon end-goals. The latter range from the avoidance of exposure to pollutants (remediation) to the full recovery of the original ecosystem (restoration). Although frequently claimed as the end-goal, restoration may often not be unachievable, because of altered hydrology, habitat fragmentation, contamination, climate change, prohibitive costs and other environmental and socio-economic boundary conditions. Mostly, the definitions of reclamation and rehabilitation may overlap in their definitions and approaches. Here we attempt the creation of a road-map that can clearly translate end-goals for each of the R4 terms. According to the definitions encountered and exposed here, reclamation, which aims to recover key ecosystem services and biogeochemical functions within a replacement ecosystem or rehabilitation, which implies a repurposing of the landscape, may be the best approaches to deal with surface mining legacies.  相似文献   
389.
We consider the resource-extraction policy of a government that is lobbied by an environmental organization and an extraction firm from foreign countries. To analyze this situation, we propose a sequential Nash bargaining solution: The government bargains with both lobbies simultaneously. Should this trilateral negotiation fail, it chooses one lobby for a bilateral negotiation. The disagreement point then is to bargain with the other lobby. Finally, should this second bilateral negotiation break down, the government chooses the welfare-maximizing policy.As long as cumulative extraction is low, such that stock-dependent extraction costs are also low and extraction profits are high, the environmental organization has a weak bargaining position, but it takes influence to reduce extraction. Once that cumulative extraction has increased so much that extraction profits are below a threshold, the bargaining positions change, and the environmental organization gets compensated by the extraction firm for not letting the trilateral negotiation fail.  相似文献   
390.
In the present study, a new sensitive and simple kinetic-spectrophotometric method for the determination of the insecticide diflubenzuron [1-(4-chlorophenyl)-3-(2,6-diflubenzoil)urea] is proposed. The method is based on the inhibited effect of diflubenzuron on the oxidation of sulphanilic acid (SA) by hydrogen peroxide in phosphate buffer in presence Cu(II) ion. Diflubenzuron was determined with linear calibration graph in the interval from 0.31 to 3.1 μg mL?1 and from 3.1 to 31.0 μg mL?1. The optimized conditions yielded a theoretical detection limit of 0.18 μg mL?1corresponding to 0.036 mg Kg?1mushroom sample based on the 3Sb criterion. The RSD is 5.03–1.83 % and 2.81–0.71 % for the concentration interval of diflubenzuron 0.31–3.1 μg mL?1and 3.1–31.0 μg mL?1, respectively. The reaction was followed spectrophotometrically at 370 nm. The kinetic parameters of the reaction are reported, and the rate equations are suggested. The developed procedure was successfully applied to the rapid determination of diflubenzuron in spiked mushroom samples of different mushroom species. The HPLC method was used like a comparative method to verify results.  相似文献   
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