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61.
烃源岩的可溶烃含量(S1)、热解烃含量(S2)和总有机碳含量(TOC)是进行烃源岩研究和评价的重要指标,以往主要通过实验室分析方法获得,时效性得不到保证。为了探讨野外快速测量这些指标的可行性,采集了乌兹别克斯坦克孜勒库姆地块10件烃源岩样品,运用地面ASD光谱仪和碳硫分析仪,分别测定了样品的可见光-近红外-短波红外(Vis-NIR-SWIR)反射光谱和S1, S2和TOC含量参数。运用光谱拟合微分,获得了上述样品反射光谱的一阶导数、二价导数等微分数据;并运用线性回归方程拟合和拟合结果统计分析,研究了这些数据同S1, S2和TOC含量之间的相关性。结果表明:烃源岩S1含量与原始光谱、光谱一阶导数、二阶导数分别有1 973, 511和239个波段相关,相关系数绝对值最大值分别为0.612, 0.823和0.889,相关性程度分别为弱、较强、极强;烃源岩S2含量与原始光谱、光谱一阶导数、二阶导数分别有2, 144和205个波段相关,相关系数绝对值最大值分别为0.561, 0.867和0.926,相关性程度分别为弱、较强、极强;烃源岩TOC含量与原始光谱无相关性,与光谱一阶导数、二阶导数分别有18、 180个波段相关,相关系数绝对值最大值分别为0.882和0.879,相关性都极强。此外, S1含量与光谱二阶导数的2 012 nm波段拟合优度最高,达0.790;S2含量与光谱二阶导数的363 nm波段拟合优度最高,达0.858;TOC含量与光谱一阶导数的2 480 nm波段拟合优度最高,达0.777。结果说明,利用可见光-近红外-短波红外反射光谱反演烃源岩S1, S2和TOC含量具有比较好的效果。为研究野外烃源岩的原位检测奠定了重要的基础。  相似文献   
62.
The local fuel concentration at the ignition position is a crucial parameter, especially for spark ignited engines. Hydrocarbon concentration can be determined by infrared transmission measurements because of the attenuation of infrared radiation in the 2940 cm−1 frequency range due to the excitation of fundamental CH-stretch vibrations of the molecules. In-cylinder measurements can be done by modified spark plugs with integrated absorption paths. A tungsten halide lamp was used in the experiments as an infrared light source. There is a non-linear relation between measured transmissions and hydrocarbon densities. So far, infrared transmission measurements have to be calibrated on absolute density values by using various hydrocarbon test gases with different concentrations. Furthermore in-cylinder transmission measurements can be calibrated at homogeneous engine operation conditions. In this case, a well mixed air/fuel composition is expected at the end of the compression stroke. Both time-consuming calibration processes lead to a new calibration procedure for band integrated transmission measurements which is presented in this study. The non-linear correlations between band integrated transmissions and absorber densities were calculated by using the absorption cross section as a spectral characteristic of absorbing molecules and the filter transmission as the spectral influence of the experimental setup. The differences between measurement and calculation can be corrected by a single measurement using a test gas with known hydrocarbon concentration. The calibration procedure was verified on temperature and pressure influences by measurements using a heatable optical cell at pressures up to 1800 kPa and within a temperature range from 298 to 473 K. Finally, the calibration procedure was adapted from cell measurements to an infrared fiber optical sensor which was used for in-cylinder measurements. An adapter for the spark plug bore enables a parallel use of a flame-ionization-detector and the optical sensor. Simultaneous propane concentration measurements were made in a motored engine with both measurement systems.  相似文献   
63.
The promotion of sulfur oxides on the selective catalytic reduction (SCR) of NO by hydrocarbons in the presence of a low concentration of sulfur oxides over Ag/Al2O3 has been investigated by a flow reaction test and in situ infrared spectroscopy. When the C3H6 (or C10H22) + NO + O2 feed-flow reaction was tested, maximum NO reduction was below 30% over fresh Ag/Al2O3. After the addition of SO2 to the feed flow, conversion increased slightly. Conversion increased further after SO2 was cut-off from the feed flow. This demonstrated that the increase in NO reduction activity of the catalyst was related to SOx adsorbed on the catalyst. SOx adsorbed on the catalytic surface (1375 cm−1) was detected by IR spectroscopy and was stable within the temperature range. NCO species, as an intermediate in NO reduction, on SOx-adsorbed Ag/Al2O3 in a C3H6 + NO + O2 feed flow was observed in in situ IR spectra during the elevation of the reaction temperature from 473 to 673 K, while it was only observed at 673 K on fresh Ag/Al2O3 under the same experimental conditions. We suggest that SOx in low concentrations depressed the combustion of reductants by contaminating hydrocarbon combustion active sites on the catalyst, resulting in an increase in NO reduction efficiency of the reductants.  相似文献   
64.
65.
The adsorption isotherms for an (amino) terminally functionalised, oligomeric polyisobutylene and for a series of alkylpropoxylate or alkylbutoxylate surfactant molecules on carbon particles, in isooctane, have been obtained. The isotherms on carbon show that the oligomer is the most strongly adsorbing species. The surfactants show some evidence of forming aggregates on the carbon surface at higher concentrations. Analysis of the adsorption isotherms indicate that the size of these aggregates is similar on the carbon particles and on steel balls, reported previously, but that in some cases the actual adsorbed amounts on the two surfaces differ considerably. Ellipsometric studies carried out in situ on steel surfaces in isooctane show that only the polymer gives a relatively thick adsorbed layer. Addition of surfactant reduces the adsorption of the oligomer. There are some differences between the thickness values reported previously using AFM, compared to those found in the current work using ellipsometry, but in both cases it would seem that some degree of multilayer adsorption is occurring for the oligomer on steel in isooctane.  相似文献   
66.
通过利用烃组成分析的方法对氧化前后以及热、光两种氧化的研究 ,发现在加氢润滑油老化实验研究中 ,光氧化的强度远远大于热氧化  相似文献   
67.
C. Wang  Z. Y. Han  M. Situ 《Shock Waves》2006,15(2):129-135
The high-speed combustible gas ignited by a hot gas jet, which is induced by shock focusing, was experimentally investigated. By use of the separation mode of shock tube, the test section of a single shock tube is split into two parts, which provide the high-speed flow of combustible gas and pilot flame of hot gas jet, respectively. In the interface of two parts of test sections the flame of jet was formed and spread to the high-speed combustible gas. Two kinds of the ignitions, 3-D “line-flame ignition” and 2-D “plane-flame ignition”, were investigated. In the condition of 3-D “line-flame ignition” of combustion, thicker hot gas jet than pure air jet, was observed in schlieren photos. In the condition of 2-D “plane-flame ignition” of combustion, the delay time of ignition and the angle of flame front in schlieren photos were measured, from which the velocity of flame propagation in the high-speed combustible gas is estimated in the range of 30–90m/s and the delay time of ignition is estimated in the range of 0.12–0.29ms. PACS 47.40.Nm; 82.40.FpPart of this paper was presented at the 5th International Workshop on Shock/Vortex Interaction, Kaohsiung, October 27–31, 2003.  相似文献   
68.
构造热演化史可以确定泥页岩在不同地质时期的成熟度状态及构造演化特征,对页岩含气性研究和资源评价都具有重要意义。综合运用包裹体测温法、构造热演化法以及盆地模拟软件Petromod对修武盆地的热演化史和埋藏史进行研究和重建。修武盆地JY1井的剥蚀厚度计算结果为4 142.75 m;自晚古生代以来热流值经历了低—高—低的变化过程;王音铺-观音堂组页岩在早志留世(434 Ma)进入生烃门限,早志留世-中志留世(434~422 Ma)为生油阶段,晚志留世-早二叠世(422~265 Ma)为生湿气阶段,早二叠世-晚侏罗世(265~145 Ma)为生干气阶段;王音铺组-观音堂组页岩早期大量生烃、长期深埋、生气时间早和抬升时间早,使得JY1井王音铺组-观音堂组页岩含气量(0.28~0.93 m3/t)并不理想。  相似文献   
69.
介绍了一种陆相断陷湖盆的盆地分析内容和方法,即含油气盆地构造岩相分析法.其以盆地二级构造带的构造岩相分析为核心.以盆地埋藏史、构造发展史、沉积充填史和油气演化史为基本研究内容,综合多学科知识和多种手段,探讨盆地内构造活动与沉积作用的内在联系以及油气分布规律.建立盆地构造岩相模式.指导油气勘探和开发.  相似文献   
70.
排烃效率对于酪根累计产烃率影响的数学模拟   总被引:1,自引:0,他引:1  
通过简化有机质成烃机理,利用有机演化过程中元素组成的变化,建立了不同排烃条件下干酪根成烃的数学模型,计算了不同演化程度时的干酪很累计产烃率和有机碳恢复系数。结合实验室模拟结果,分析讨论了排烃条件对有机演化进程的影响。该方法可为油气资源评价提供较为系统准确的参数。  相似文献   
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