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81.
TR-01稠油乳化降粘剂研究   总被引:4,自引:0,他引:4  
针对河南油田井楼区块稠油,自制TR-01乳化降粘剂,通过实验研究了其降粘性能、稳定性,确定了降粘剂TR-01最佳浓度为0.3%、最佳油水比为70∶30。实验结果表明:TR-01乳化降粘剂对井楼区块油井的普遍适用性较强,具有较好的乳化降粘作用(降粘率达到99%以上),地层水对其降粘效果影响不大。其中的纳米成分能增加对污水中悬浮物的吸附能力和絮凝能力,对油田污水处理起到积极作用。  相似文献   
82.
城市家用天然气安全管理的研究   总被引:1,自引:1,他引:0  
通过对100家广州市天然气家庭用户使用情况进行调查,主要针对天然气使用、燃气设施保护和安全意识等诸多问题,运用事故致因理论,分析其成因规律,提出从事故发生的根本原因入手,运用"预防为主、善后为辅"的积极、主动的方法,把事故消除在起始或孕育阶段。调查结果显示:造成城市燃气应用系统事故的原因主要包括:用户燃具不正确的选择、燃气设备安装不当、燃气安全知识水平不高、安全意识不强、燃具产品和服务质量良莠不齐等。并以事故预防控制理论为指导,提出广州市天然气应用预防与安全管理应采取的技术、教育、强化等3方面对策。  相似文献   
83.
A comparative study on the metazooplankton community was conducted in three different eutrophic areas, including Lake Wulihu, Meiliang Bay and the central open water area, in Lake Taihu from Oct. 2003 to Sep. 2004. Forty metazooplankton species were identified in Lake Wulihu, 37 in Meiliang Bay, and 34 in the central open water area. The annual average abundance of metazooplankton was 218 ind. l(-1) in the central open water area, 309 ind. l(-1) in Meiliang Bay, and 384 ind. l(-1) in Lake Wulihu. In Lake Wulihu, rotifers, Brachionus calyciflorus and Brachionus angularis, were the dominant species, which contributed 20.9% and 17.2% to the total metazooplankton abundance. Bosmina coregoni and Ceriodaphnia cornuta were the dominant species, contributing 20.4% and 11.3% of the total in Meiliang Bay, and contributing 21.6% and 16.2% of the total in the central open water area. There was a significant positive relationship between rotifers abundance and Secchi transparency. Cladoceran and copepod abundance were positively correlated with total phosphorus and water temperature. Our results show that structures of metazooplankton community differ between the three lake areas with different eutrophic states in Lake Taihu.  相似文献   
84.
In Europe, the European Union Landfill Directive aims to reduce the negative environmental impacts of landfilling. This is mainly to be achieved by reducing the quantity of organic matter deposited, through measures such as the separate collection and recycling of the organic waste stream or pretreatment of residual wastes before landfilling. Other than incineration or other thermal processes, mechanical biological treatment is playing an increasingly important role. This study was conducted to seek the benefits of municipal solid waste (MSW) pretreatment, as well as the differences in methane production from the landfilling of untreated and mechanically/biologically treated (MBT) MSW using GasSim simulation. Results demonstrated that methane production rates vary significantly among waste fractions. Those that contribute most to methane generation (organic material and potentially reusable or recyclable material) could be targeted and treated before landfilling. The statistic relationship from the first phase of the study indicated that to match the increasingly stringent landfill waste organic content allowance, local councils should prioritize the reduction/sorting of certain targeted fractions, such as paper, card, green waste, and other putrescibles from MSW. Moreover, mechanical treatment alone produces organic-rich waste called mechanically sorted organic residues (MSORs), which can be viewed as an organic content concentration process. Mechanically and biologically pretreated waste, on the other hand, differs significantly from untreated MSW and MSORs. This work demonstrated that if efficient mechanical-biological treatment is used, considerable reductions in biological activity, landfill gas production, and energy content/total organic carbon could be achieved. Using GasSim, reductions in methane production of >74% have been simulated if a 90% organic content reduction can be achieved during biological treatment on MSORs. A 50-60% organic content reduction by following biological treatment can turn MSOR properties only into normal MSW equivalent though considerably less volume.  相似文献   
85.
86.
烟气脱硝技术及在我国的应用   总被引:3,自引:0,他引:3  
氮氧化物气体是危害最大、最难处理的大气污染物之一。随着经济的发展,有效控制燃煤造成的大气污染已经刻不容缓,特别是控制燃煤过程中的氮氧化物,烟气脱硝技术显得相当重要。本文分析了几种常用的烟气脱硝技术(选择性催化还原脱硝技术、选择性非催化还原脱硝技术、碱性溶液吸收法和等离子体活化法等)的原理、技术特点以及在我国的应用情况。  相似文献   
87.
稳态条件下,采用厌氧折流板反应器(anaerobic baffled reactor,ABR)处理山梨酸废水并进行基质降解动力学研究.实验表明,在污泥负荷为0.54~1.63 kg COD/(kg VSS·d)的范围内,COD去除率随着负荷的增加从85%降到55%.各隔室出水COD沿程递减,前3个隔室承担了去除COD的重要作用,但随着污泥负荷的增加,后部承担的COD去除率比例增大.基于各串联隔室完全混合的假定,推导ABR中山梨酸废水的基质降解动力学方程,并通过实验确定相关动力学参数及相应的动力学方程.实测值与预测值基本吻合.  相似文献   
88.
A modified LC-MS method for the analysis of mepiquat residue in wheat, potato, and soil was developed and validated. A hydrophilic interaction liquid chromatographic column has been successfully used to retain and separate the mepiquat. Mepiquat residue dynamics and final residues in supervised field trials at Good Agricultural Practice (GAP) conditions in wheat, potato, and soil were studied. The limits of quantification for mepiquat in all samples were all 0.007 mg kg?1, which were lower than their maximum residue limits. At fortification levels of 0.04, 0.2, and 2 mg kg?1 in all samples, recoveries ranged from 77.5 to 116.4 % with relative standard deviations of 0.4–7.9 % (n?=?5). The dissipation half-lives (T 1/2) of mepiquat in soil (wheat), wheat plants, soil (potato), and potato plants were 4.5–6.3, 3.0–5.6, 2.2–4.6, and 2.4–3.2 days, respectively. The final residues of mepiquat were below 0.153 mg kg?1 in soil (wheat), 0.052–1.900 mg kg?1 in wheat, below 0.072 mg kg?1 in soil (potato), and below 1.173 mg kg?1 in potato at harvest time. Moreover, pesticide risk assessment for all the detected residues was conducted. A maximum 0.0012 % of acceptable daily intake (150 mg kg?1) for national estimated daily intake indicated low dietary risk of these products.  相似文献   
89.
Evenly distributed sampling design is generally considered as an efficient sampling design. It is widely used in sampling for the environmental survey. In this paper, we present a novel method for generating N evenly distributed samples within a given irregular polygon via simulating the movements of some ideal homogeneous point charges. Initially, charges are randomly put into the sampling region; then, they are freed and held orderly; and after enough runs, the charges will finally reach a stable state with all of them having a zero resultant force and velocity; and so they distribute evenly within the region. Their layout can thus be considered as an evenly distributed sampling design. The main advantages of this method are: (1) it is easy to understand and implement; (2) it is efficient in both running and generating better designs. Analysis and experimental results indicate that this method is an efficient and robust method for generating even sampling designs for 2D polygonal sampling region.  相似文献   
90.
基于地面观测数据,分析了"十一五"和"十二五"期间宁波市酸雨污染特征变化趋势。结果表明,2015年降水pH从2010年的4.37上升到4.89;2010—2015年酸雨发生频率降低了17.4百分点;重酸雨区范围不断缩小,轻酸雨区范围不断扩大,酸雨污染程度有所改善。降水中化学组成变化显示,与"十一五"末相比,2015年除NO_3~-、Cl~-外其他离子浓度均有所下降;2015年SO_3~(2-)与NO_3~-的当量浓度之比从2010年的3.10下降到1.73,表明酸雨污染从硫酸型向硫酸与硝酸混合型转变。  相似文献   
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