临南地区石油运移方向与成藏期次研究   总被引：11，自引：0，他引：11  

陈庆春  林玉祥  唐洪三 《沉积学报》2001,19(4):611-616

根据原油及油砂抽提物中含氮化合物分析、原油生物标志成熟度参数及储层流体包裹体烃类成分分析,研究了临南地区石油运移的方向、距离、成藏期次。结果表明临南油田仅有一期油气运聚成藏过程,属中新世末形成的成熟原油,4 甲基甾烷含量较高。曲堤油田存在两期油气运聚成藏过程,早期原油成熟度低,4 甲基甾烷含量低,运移距离较远,成藏后大部分散失 ;晚期充注的原油成熟度较高,4 甲基甾烷含量也较高,并保存至今。  相似文献   

Element budgets of pine stands on lignite and pyrite containing mine soils     

Martin Gast  Wolfgang Schaaf  Joerg Scherzer  Rudolf Wilden  Bernd U. Schneider  Reinhard F. Hüttl 《Journal of Geochemical Exploration》2001,73(2):196

To analyze the development of pine ecosystems on lignite and pyrite containing mine soils, four pine stands with ages of 3–35 years were investigated in a chronosequence approach. Bulk precipitation, throughfall and soil solution in depths of 20, 40, 70 and 100 cm were studied over a three-year period to determine element fluxes in these forest ecosystems on extreme acidic and saline soils.Element budgets are controlled by the processes induced by pyrite oxidation such as intensive weathering of primary minerals, precipitation and leaching of secondary phases.Despite low water fluxes, element outputs can reach extraordinary high values due to very high concentrations in the soil solution. Although element outputs decrease drastically with stand age, respectively, site age, they exceed those of comparable pine stands on non-mine sites. Nitrogen release from the lignite fraction represents a special characteristic of the examined substrates. Nitrogen losses beneath the rooted zone can be 34 kg N ha⁻¹ yr⁻¹ in 100 cm depth. Element input and output in the examined ecosystems are far from balance. Closed cycling of nutrients seems to be recognizable in the case of potassium.  相似文献   

Processing of oxidised nitrogen compounds by passage through winter-time orographic cloud     

R. N. Colvile  T. W. Choularton  J. N. Cape  B. J. Bandy  K. N. Bower  R. A. Burgess  T. J. Davies  G. J. Dollard  M. W. Gallagher  K. J. Hargreaves  B. M. R. Jones  S. A. Penkett  R. L. Storeton-West 《Journal of Atmospheric Chemistry》1996,24(3):211-239

Four case studies are described, from a three-site field experiment in October/November 1991 using the Great Dun Fell flow-through reactor hill cap cloud in rural Northern England. Measurements of total odd-nitrogen nitrogen oxides (NO _y ) made on either side of the hill, before and after the air flowed through the cloud, showed that 10 to 50% of the NO _y , called NO _z , was neither NO nor NO₂. This NO _z failed to exhibit a diurnal variation and was often higher after passage through cloud than before. No evidence of conversion of NO _z to NO₃ ^- in cloud was found. A simple box model of gas-phase chemistry in air before it reached the cloud, including scavenging of NO₃ and N₂O₅ by aerosol of surface area proportional to the NO₂ mixing ratio, shows that NO₃ and N₂O₅ may build up in the boundary layer by night only if stable stratification insulates the air from emissions of NO. This may explain the lack of evidence for N₂O₅ forming NO₃ ^- in cloud under well-mixed conditions in 1991, in contrast with observations under stably stratified conditions during previous experiments when evidence of N₂O₅ was found. Inside the cloud, some variations in the calculated total atmospheric loading of HNO₂ and the cloud liquid water content were related to each other. Also, indications of conversion of NO _x to NO _z were found. To explain these observations, scavenging of NO _x and HNO₂ by cloud droplets and/or aqueous-phase oxidation of NO₂ ^- by nitrate radicals are considered. When cloud acidity was being produced by aqueous-phase oxidation of NO _x or SO₂, NO₃ ^- which had entered the cloud as aerosol particles was liberated as HNO₃ vapour. When no aqueous-phase production of acidity was occurring, the reverse, conversion of scavenged HNO₃ to particulate NO₃ ^-, was observed.  相似文献   

Surface NO and NO2 mixing ratios measured between 30° N and 30° S in the Atlantic region     

F. Rohrer  D. Brüning 《Journal of Atmospheric Chemistry》1992,15(3-4):253-267

Surface NO and NO₂ mixing ratios were measured aboard the research vessel Polarstern during the mission ANT VII/1 from 24 September to 5 October 1988. The measurements were taken along the meridian at 30° W in the Atlantic region covering latitudes between 30° N and 30° S. The average mixing ratios were about 12 pptv NO/30 pptv NO₂ in the Northern Hemisphere and about 7 pptv NO/22 pptv NO₂ in the Southern. Elevated mixing ratios of 20 pptv NO/70 pptv NO₂ were found at 12° N (probably due to air masses originating from the surface of West Africa) and in the region of the ITCZ between 8° N and 5° N. Because of probable contamination by the ship, the measured mixing ratios mostly represent upper limits.  相似文献   

What controls levels of dissolved phosphate and ammonium in surface waters?   总被引：4，自引：0，他引：4  

Walter K. Dodds 《Aquatic Sciences - Research Across Boundaries》1993,55(2):132-142

Dissolved inorganic nutrient pools are small relative to particulate pools, and dissolved pools turnover rapidly. It has been observed that pools change little from day to day on the sampling scales usually employed. A simple model is presented where uptake and regeneration rates balance to cause a local steady state concentration for dissolved inorganic nutrients. Enrichment and dilution perturbation experiments with lake water support the idea of steady state nutrient concentrations. Although inorganic nutrient concentrations are often controlled by biota, the absolute concentrations present tell little about the activity of that biota.  相似文献   

Assessment of the Uncertainties in the NO2 and O3 Measurements by Visible Spectrometers     

M. Koike  Y. Kondo  W.A. Matthews  P.V. Johnston  H. Nakajima  A. Kawaguchi  H. Nakane  I. Murata  A. Budiyono  M. Kanada  N. Toriyama 《Journal of Atmospheric Chemistry》1999,32(1):121-145

The column amounts of nitrogen dioxide (NO2) and ozone (O3) were measured using a visible spectrometer based on the twilight zenith-sky technique at two observatories located at similar latitudes in the northern part of Japan separated by a distance of 150 km. The measurements began in April 1991 at the Moshiri Observatory (44.4°N, 142.3°E) and in April 1994 at the Rikubetsu Observatory (43.5°N, 143.8°E). Since weather conditions and the possible influence from tropospheric pollution were not always identical at these two observatories, the overall accuracy of the measurements was studied comparing these data sets. The first year data obtained at a solar zenith angle of 90 degrees indicated that the NO2 slant column values at sunrise and sunset agreed within 0.36 and 0.54 × 1016 cm-2, respectively, corresponding to 5 % (June) and to 12 % (December) of the columns. The O3 values agreed within 0.76 × 1019 cm-2, corresponding to 4 % (March) 6 % (August) of the columns, although a part of the difference was systematic. The O3 column amounts were also compared to those obtained by the Dobson spectrometer at Sapporo (43.5°N, 143.8°E), whose latitude is similar to these observatories. When an air mass factor of 17.5 was used, the two-year Moshiri vertical column values agreed with the Dobson direct sun values to within 15 Dobson Units, or 3 6 % of the column. The difference between the two values was found to be due partly to the change in the air mass factor caused by seasonal and day-to-day changes in the shape of the O3 vertical profiles. These results confirm the reliability of the NO2 and O3 measurements by visible spectrometers at these sites for the Network for the Detection of Stratospheric Change (NDSC).  相似文献   

Carbon sources of fish in an Amazonian floodplain lake     

A. Cristina B. Oliveira  M. Gercilia M. Soares  L. Antonio. Martinelli  M. Zacarias. Moreira 《Aquatic Sciences - Research Across Boundaries》2006,68(2):229-238

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石家庄地面水回渗地下过程的氮行为影响试验研究   总被引：1，自引：0，他引：1  

张云  王秀艳  刘长礼  张明 《地球学报》2007,28(1):43-49

石家庄是我国北方地下水位下降较大的城市之一,利用其毗邻滹沱河宽阔河滩,地面水可直接入渗补给地下水的有利水文地质条件,实施地面水回渗地下工程,将具有现实意义.为探索地面水回渗后的水质变化,该文针对地面水在回渗过程中对水质起限制性影响的氮行为作用进行了模拟试验研究.结果显示,利用2 m厚的滹沱河细砂土及与粘土按一定比例的混合砂土层,可对间歇式实施地面水回渗中的铵氮组分形成一定容量的截留去除,并且该截留量又在随回渗次数的增加而缓慢下降,当采用人工增加环境碱度及湿度的办法后可消除这种下降.同时,还显示对回渗水中硝酸氮的去除率不高,但若采用人工添加乙醇碳源和接种优势脱氮微生物菌种方法,硝酸氮的去除率将会得到较大提高.  相似文献   

半微量凯氏法测定土壤全氮量的不确定度评定   总被引：2，自引：2，他引：2  

白金峰  胡外英  张勤  周建辉 《岩矿测试》2007,26(1):40-44

以半微量凯氏法测定土壤中全氮量为例，对测定结果的不确定度来源进行了详细分析，对测定过程中的主要不确定度分量进行了合理评定，包括样品和标准物质硼砂的称量引入的不确定度，硼砂的纯度引入的不确定度，容量瓶、移液管和滴定管的体积引入的不确定度．相关元素的摩尔质量引入的不确定度以及测量的重复性引入的不确定度。最后合成标准不确定度．通过乘以95％置信概率下的扩展因子2获得测量结果的扩展不确定度。  相似文献   

多目标地球化学调查土壤样品中氮和碳的快速测定   总被引：2，自引：1，他引：2  

于兆水  胡外英张勤 《岩矿测试》2007,26(3):235-237

详细研究了元素分析仪的工作条件，建立了直接固体进样同时测定多目标地球化学调查土壤样苎支氮、碳的方法。方法简便、快速，检出限为氮14．5μg／g、碳0．013％。经土壤国家一级标准物质分析验证，测定值与标准值相符，精密度（RSD，n=12）为氮1．49％-3．27％、碳0.64％～3.63％。  相似文献