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461.
硫化氢是一种剧毒和较强腐蚀性的气体,近年来在辽河油田一些地区相继出现,特别是稠油热采区块出现了较高浓度的硫化氢。硫化氢的存在已经威胁到油田的安全生产,并成为油气勘探开发过程中必须解决的问题。本文对辽河油气稠油热现场硫化氢的预防与治理提出了一些建议。  相似文献   
462.
To understand the effects of long-term amendment of organic manure and N fertilizer on N2O emission in the North China Plain, a laboratory incubation at different temperatures and soil moistures were carried out using soils treated with organic manure (OM), half organic manure plus half fertilizer N (HOM), fertilizer NPK (NPK), fertilizer NP (NP), fertilizer NK (NK), fertilizer PK (NK) and control (CK) since 1989. Cumulative N2O emission in OM soil during the 17 d incubation period was slightly higher than in NPK soil under optimum nitrification conditions (25℃ and 60% water-filled pore space, WFPS), but more than twice under the optimum denitrification conditions (35℃ and 90% WFPS). N2O produced by denitrification was 2.1-2.3 times greater than that by nitrification in OM and HOM soils, but only 1.5 times greater in NPK and NP soils. These results implied that the long-term amendment of organic manure could significantly increase the N2O emission via denitrification in OM soil as compared to NPK soil. This is quite different from field measurement between OM soil and NPK soil. Substantial inhibition of the formation of anaerobic environment for denitrification in field might result in no marked difference in N2O emission between OM and NPK soils. This is due in part to more rapid oxygen diffusion in coarse textured soils than consumption by aerobic microbes until WFPS was 75% and to low easily decomposed organic C of organic manure. This finding suggested that addition of organic manure in the tested sandy loam might be a good management option since it seldom caused a burst of N2O emission but sequestered atmospheric C and maintained efficiently applied N in soil.  相似文献   
463.
A stain-based screening method was developed to screen different catalyst coatings for their germicidal activity. A Baclight dead/live bacteria viability kit (invitrogen, molecular probes) was used for staining the cell. The screening was carried out following a standard procedure. This included loading cell suspension to solid surface and maintaining contact for 30 min, then staining with a mixture containing dyes. The stained cells were observed using an epifluorescent microscope and photographed with a CCD camera under UV. Metal-doped TiO2 coatings on AI plates were prepared and tested for non-UV germicidal activity without using UV. It was tested using model microorganisms such as Bakers Yeast (Saccharomyces cerevisiae), Bacillus subtilis, Pseudomonas putida, and Escherichia coli. On the basis of the germicidal activity of catalyst and the degree of damage caused to the cells, the stained cells may appear green (viable), green with red or yellow nuclei and yellow (compromised) or red (nonviable). According to their stained color, cells were counted to calculate the percentage of dead, live, and compromised cells. Compromised cells are cells that grow very slowly after reculturing indicating a degree of reversible cell damage. Screening the germicidal activity using this staining method is accurate and efficient, and requires less time than the culture-based method. A modification to the procedure for measuring germicidal activity of rough surfaces or fibrous coatings was developed. Both TiO2 and metal-doped TiO2 (Ag, Pt, Au, Cu) possess non-UV based germicidal activity. The germicidal activity of TiO2 was found to be related with its wetting property and can be improved by UV irradiation before testing. It is not greatly affected by contact time, indicating a fast acting germicidal activity.  相似文献   
464.
城市是人类生产和生活的中心,超过75%的温室气体从城市产生,其中又以城市产业部门能源消费和工业过程非能源产生的CO2为主。本文基于投入产出模型,评价城市产业部门3个不同层次的CO2排放。以重庆为案例,核算其2002-2008年产业部门三个层次的CO2排放,包括能源消费直接排放、购买电力间接排放和全生命周期排放,并进行多层次对比。结果显示传统能源消耗和购买电力为对象的核算方法低估了产业部门CO2排放水平。2002-2008年,重庆各产业部门排放量逐年增加,碳排放强度整体呈现下降趋势。煤炭开采和洗选业、非金属矿采选业、非金属矿物制品业、电力、热力的生产和供应业,化学工业、金属冶炼及压延加工业、交通运输、仓储及邮电通讯业部门共7大行业是重庆碳排放的重点行业。部门交通设备制造业是重庆的优势产业,排放总量大,但是排放强度却相对较小,因此应大力发展该产业以促进重庆市低碳经济的发展。  相似文献   
465.
根据云南省能源消费量,计算了由能源消费产生的CO2排放量及单位GDP碳排放强度。结果表明:近10年来,随着社会经济的快速发展,云南省能源消费及能源消费导致的CO2排放总量也呈现出显著上升的趋势。云南的碳排放强度高于全国平均水平,但人均碳排放量低于全国平均水平。以工业为主的第二产业是能源消费及碳排放的主体,其碳排放占总量的75%。  相似文献   
466.
通过对WJ-7型扣件中60Si2MnA弹条在拉伸-扭转试验过程发生断裂的原因进行分析和数值模拟研究,得出弹条断裂的原因.对60Si2MnA弹条承受的荷载进行分析可知,WJ-7型扣件在铁垫板与弹条后端接触区域内弯处应力集中最大,是造成弹条断裂破坏的主要原因之一,而弹条断裂的根本原因是弹条长期处于极限强度下工作,使弹条最终...  相似文献   
467.
The degradation of polyacrylamide (PAM) in simulate wastewater was studied in UV/Fenton/C4H4O62? system. The factors such as molecular ratio of H2O2/Fe2+/C4H4O62?, pH, and the dosage of Fenton reagent that could affect the PAM degradation in the UV/Fenton/C4H4O62? system were investigated. The experimental results showed that adding C4H4O62? to UV/Fenton system could form photosensitive ferrous complexes, which led to higher degradation efficiency of PAM. The degradation rate of PAM could be up to 95.2% under the following conditions: the concentration of H2O2, Fe2+, and C4H4O62? were 22.5, 2.25, and 2.25 mmol/L, respectively (i.e., molecular ratio of H2O2/Fe2+/C4H4O62? was 10:1:1), the pH value was 3.0.  相似文献   
468.
洪泛区的开发利用,必然会导致洪泛区林地糙率的改变。河漫滩也是河流洪泛区的一部分。洪泛区糙率的减小,会使河水流速增大,从而减小鱼类可用栖息地面积。因此,在洪水发生时,为了给鱼类提供避险场所,保护有效栖息地面积,需研究洪泛区林地的开发对鱼类的影响。利用River 2D软件模拟在一定频率的洪水条件下,不同的河漫滩糙率对应的鱼类栖息地加权可用面积(WUA),分析了糙率的改变对河流鱼类栖息地的影响。结果表明:随着河漫滩糙率的降低,加权可用面积(WUA)逐渐减小,河漫滩范围内WUA的变化幅度比较大,河漫滩的特性对鱼类栖息地面积的影响很大。洪泛区植被的砍伐,会使鱼类栖息地面积减小。因此,应防止洪泛区的过度开发,保护河流生态环境。  相似文献   
469.
在旅游业节能减排形势严峻的背景下,深入研究中国旅游业CO_2排放问题,制定科学的区域节能减排政策已刻不容缓。本文首先运用"自下而上"法,估算了1993-2012年中国整体旅游业、旅游业各分部门、大陆各省区(不含西藏)旅游业CO_2排放量。在此基础上,对全国及三大地带旅游业CO_2排放的总体特征进行分析;利用Theil指数法分析了中国旅游业CO_2排放强度的区域差异、区域内差异和区域间差异;运用AreView软件对中国旅游业CO_2排放强度的省际差异进行直观图示。分析结果显示:1993-2012年,中国旅游业CO_2排放量从1 480.868×10~4t升至6 274.129×10~4t;全国及三大地带旅游业CO_2排放强度整体上呈现出先显著下降、再缓慢梯度下降的趋势;中国旅游业CO_2排放强度空间分布不均匀,东部地区旅游业CO_2排放强度低于中部和西部地区;中国旅游业CO_2排放强度的区域总体差异、区域间差异和区域内差异整体呈逐渐缩小的趋势,区域间差异对总体差异的贡献率为94%-98%,区域间差异占主导地位;中国旅游业CO_2排放强度省际差异明显,属于旅游业CO_2排放强度弱显著区的省区基本位于东部沿海地区,河北、湖南、河南、广西、甘肃和新疆等省区频繁出现在旅游业CO_2排放强度强显著区之列,因此上述省区应是中国旅游业CO_2未来节能减排的区域重点。据此提出差别化的CO_2减排对策:东部地区应通过技术改进和调整产业结构、能源消费结构来降低CO_2排放强度,并以此带动中部和西部地区旅游业节能减排;中部和西部地区应加强与东部地区合作,将提高能源使用率、降低CO_2排放强度作为旅游业减排工作的重点。  相似文献   
470.
Dissipation kinetics of mesotrione, a new triketone herbicide, sprayed on soil from Limagne (Puy-de-Dôme, France) showed that the soil microflora were able to biotransform it.Bacteria from this soil were cultured in mineral salt solution supplemented with mesotrione as sole source of carbon for the isolation of mesotrione-degrading bacteria. The bacterial community structure of the enrichment cultures was analyzed by temporal temperature gradient gel electrophoresis (TTGE). The TTGE fingerprints revealed that mesotrione had an impact on bacterial community structure only at its highest concentrations and showed mesotrione-sensitive and mesotrione-adapted strains. Two adapted strains, identified as Bacillus sp. and Arthrobacter sp., were isolated by colony hybridization methods.Biodegradation assays showed that only the Bacillus sp. strain was able to completely and rapidly biotransform mesotrione. Among several metabolites formed, 2-amino-4-methylsulfonylbenzoic acid (AMBA) accumulated in the medium. Although sulcotrione has a chemical structure closely resembling that of mesotrione, the isolates were unable to degrade it.  相似文献   
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