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1.
吐哈盆地侏罗纪煤中主要组分结构特征与生烃性分析 总被引:10,自引:0,他引:10
在高纯度煤岩显微组分分离富集的基础上,应用透射式显微傅里叶红外光谱技术 (Micro FTIR),对吐哈盆地侏罗纪煤中的主要组分-镜质体、丝质体、角质体、藻类体的结构组成进行了测定。结果表明 :藻类体主要由长链脂族结构组成,芳香结构含量相对较少;角质体和基质镜质体中含有较丰富的芳香结构以及长链脂族结构;而丝质体则主要由芳香结构组成,脂族结构含量很少。显微组分的这种结构特征决定了藻类体具有很高的生烃潜力、角质体和镜质体的生烃潜力中等、而丝质体的生烃潜力则很低。对于吐哈盆地煤成油来说,由于藻类体主要由长链脂族结构组成,并且生烃潜力也高,因此其具有高的液态烃产率、丝质体的产油率最小、角质体和镜质体的液态烃产率中等。由于镜质体是本区煤中含量最高的组分。因此,对于吐哈盆地所形成的具有工业规模的油田来说,镜质体应该是主要的贡献组分之一。但对于富含藻类体的厚层状烛藻煤,由于它类型好,品质高、生烃潜力大、以中长链脂族结构为主,是煤成油最理想的源岩。 相似文献
2.
Annealing at 400?T?600 °C (40?P?60 MPa and HM buffer-controlled f(O2)) of tourmalines synthesised at the same T and P with NNO buffer induces an oxidation of Fe2+ into Fe3+ in some Y sites only (Mössbauer Spectroscopy data). Annealing in the same conditions of natural tourmalines is consistent with these results. FTIR spectroscopy shows that oxidation of Fe2+ into Fe3+ is charge-balanced by deprotonation of the external OH(3) groups. To cite this article: Y. Fuchs et al., C. R. Geoscience 334 (2002) 245–249. 相似文献
3.
用显微荧光和显微傅立叶红外光谱研究显微组分的热演化规律 总被引:4,自引:0,他引:4
镜质体反射率是确定油源岩成熟度最广泛使用的参数,显微荧光强度及其变化也已成为检测烃源岩有机质生烃尤其是生油的标志之一,而红外光谱在研究生油母质干酪根的结构、类型和生烃潜力等方面均取得了大量的研究成果,特别是傅立叶红外显微镜的问世,给单显微组分提供了一种有效的研究手段。本文应用上述方法对一套人工熟化样品进行了检测和分析,探讨了显微组分的光性演变特征和化学成分的变化规律,并建立了显微组分的生油模式。 相似文献
4.
Products and mechanisms for the gas-phase reactions of NO3 radicals with CH2=CHCl, CH2=CCl2, CHCl=CCl2,cis-CHCl=CHCl andtrans-CHCl=CHCl in air have been studied. The experiments were carried out at 295±2 K and 740±5 Torr in a 480-L Teflon-coated reaction chamber and at 295±2 K and 760±5 Torr in a 250-L stainless steel reactor. NO3 was generated by the thermal dissociation of N2O5. Experiments with15NO3 and CD2CDCl have also been performed. The initially formed nitrate peroxynitrates decay into carbonyl compounds, nitrates, HCl and ClNO2. In adidtion, there are indications of nitrooxy acid chlorides being produced. The reactions with CH2=CCl2 and CHCl=CCl2 are more complex due to release of chlorine atoms which eventually lead to formation of chloroacid chlorides.A general reaction mechanism is proposed and the observed concentration-time profiles of reactants and products are simulated for each compound. The rate constants for the initial step of NO3 addition to the chloroethenes are determined as: (2.6±0.5, 9.4±0.9, 2.0±0.4 and 1.4±0.4) × 10–16 cm3 molecule–1 s–1 for CH2=CHCl, CH2=CCl2, CHCl=CCl2 andcis-CHCl=CHCl, respectively. 相似文献
5.
The incorporation of hydrogen (deuterium) into the coesite structure was investigated at pressures from 3.1 to 7.5 GPa and
temperatures of 700, 800, and 1100 °C. Hydrogen could only be incorporated into the coesite structure at pressures greater
5.0 GPa and 1100 °C . No correlation between the concentration of trace elements such as Al and B and the hydrogen content
was observed based on ion probe analysis (1335 ± 16 H ppm and 17 ± 1 Al ppm at 7.5 GPa, 1100 °C). The FTIR spectra show three
relatively intense bands at 3575, 3516, and 3459 cm−1 (ν1 to ν3, respectively) and two very weak bands at 3296 and 3210 cm−1 (ν4 and ν5, respectively). The band at 3516 cm−1 is strongly asymmetric and can be resolved into two bands, 3528 (ν2a) and 3508 (ν2b) cm−1, with nearly identical areas. Polarized infrared absorption spectra of coesite single-crystal slabs, cut parallel to (0 1
0) and (1 0 0), were collected to locate the OH dipoles in the structure and to calibrate the IR spectroscopy for quantitative
analysis of OH in coesite (ɛ
i
,tot=190 000 ± 30 000 l mol−1
H2O cm−2). The polarized spectra revealed a strong pleochroism of the OH bands. High-pressure FTIR spectra at pressures up to 8 GPa
were performed in a diamond-anvil cell to gain further insight into incorporation mechanism of OH in coesite. The peak positions
of the ν1, ν2, and ν3 bands decrease linearly with pressure. The mode Grüneisen parameters for ν1, ν2, and ν3 are −0.074, −0.144 and −0.398, respectively. There is a linear increase of the pressure derivatives with band position which
follows the trend proposed by Hofmeister et al. (1999). The full widths at half maximum (FWHM) of the ν1, ν2, and ν3 bands increase from 35, 21, and 28 cm−1 in the spectra at ambient conditions to 71, 68, and 105 in the 8 GPa spectra, respectively. On the basis of these results,
a model for the incorporation of hydrogen in coesite was developed: the OH defects are introduced into the structure by the
substitution Si4+(Si2)+4O2−= [4]□(Si2) + 4OH−, which gives rise to four vibrations, ν1, ν2a, ν2b, and ν3. Because the OH(D)-bearing samples do contain traces of Al and B, the bands ν4 and ν5 may be coupled to Al and/or B substitution.
Received: 19 December 2000 / Accepted: 23 April 2001 相似文献
6.
利用偏振喇曼光谱(PRS)和傅里叶变换红外光谱(FTIR)研究了三种不同成因电气石单晶的振动谱学特征。PRS研究表明电气石结构中三个阴离子团(即[Si6O18]^12-、[BO3]^3-、[OH]^-)的喇曼谱在平行c轴方向(//NE)比垂直c轴方向(//NO)敏锐,而且[OH]^-喇曼光谱只在平行c轴的PRS中才观察到。不同成因电气石中[OH]^-占位不同。结合FTIR研究发现在伟晶型和热液型的 相似文献
7.
生物成因与无机成因文石的FTIR光谱区别 总被引:4,自引:1,他引:4
对16种贝壳交叉页片层中生物成因文石的FT IR谱进行测量,并与无机成因文石进行对比和统计分析后,首次发现生物成因与无机成因文石的FT IR光谱有明显可区分的特征,生物成因文石2ν带(面外弯曲振动)频率平均值为863.4 cm-1,而无机成因文石该带的平均值为855.5 cm-1,两者频率位移达7.9 cm-1。因此文石的2ν带可作为指纹带鉴别生物和无机成因文石。 相似文献
8.
傅立叶变换红外光谱联用技术在化石燃料分析中的应用 总被引:2,自引:0,他引:2
对傅立叶变换红外光谱联用技术在化石燃料分析中的应用进行了较全面的总结评述,重点介绍了气相色谱/红外光谱联机、高压液相色谱/红外光谱联机、薄层色谱/红外光谱联机、超临界流体色谱/红外光谱联机、裂解色谱/红外光谱联机、热重分析/红外光谱联机、气相色谱/红外光谱/质谱三机联用技术等在化石燃料的结构组分分析、成因机理研究及其勘探等诸方面的重要应用,尤其是在芳香族化合物和几何异构体的分离鉴定方面发挥出的突出功效。引用文献59篇。 相似文献
9.
W. Bell C. Paton Walsh P.T. Woods T.D. Gardiner M.P. Chipperfield A.M. Lee 《Journal of Atmospheric Chemistry》1998,30(1):131-140
We outline how ground-based Fourier transform infrared (FTIR) measurements of stratospheric trace species, obtained with high temporal resolution, could be used to detect filaments of polar vortex air at mid-latitudes and therefore test high spatial resolution chemical transport models (CTMs). Vertical column abundances of HCl, ClONO2, HNO3, N2O and HF have been obtained from FTIR solar absorption measurements made throughout the day from Aberdeen, UK (57°N, 2°W) on several days during winter/spring 1993/94 and 1994/95. The short-timescale ( 2 hours) variability observed in the columns is attributed to real atmospheric variations and is often associated with the passage of high latitude air over Aberdeen. This is confirmed by 3D modelling studies which qualitatively reproduce and rationalise the observed changes in the column data on January 19 1994, January 20 1995 and February 26 1995. We describe the viewing geometry of ground-based FTIR measurements and we suggest a measurement strategy which should maximise the information retrieved on horizontal gradients in stratospheric trace species columns from FTIR measurements. 相似文献
10.