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This paper deals with monoterpinenese in Oldnawa Trough sediments, which have been identified by TLC and GC-MS-DS. Three kinds of monoterpinene have been recognized:cyclohexene, I-methyl-3- ( 1-methylethenyl ), cyclohexene, 1-methylethenyl-5- ( 1 -methylethenyl )and cyclohexene, 1-methyl-4-(1-methylethylidene). These monoterpinenes are considered to have been derived from terrigenous higher plant detritus and are recognized as a new type of terrigenous markers. 相似文献
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Ten stenols and stanols were identified by TLC , GC and GC-MS-DS in a marine sediment core from Beibu Bay , the South China Sea .C27, C28 and C29 A5 stenols and 5a- stanols mainly come from zoopiankton, algae and phytoplankton in marine environment. C29 24-ethylcholest- 5 - en- 3B- ol is thought to indicate input of terrigenous organic matter . The increase of C27 . C28 and C29 5a-stanol /5 stenol ratios with sediment depth shows the evolution of stenols and stanols in the marine sediment core . 相似文献
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Compositional data on the sterol and alcohol fractions isolated from deep-sea marine sediments from the Okinawa Trough were obtained to determine the relative contribution from. marine and terrestrial inputs. Following extraction, the sterol plus alcohol fraction was isolated by layer chromatography, derivatized with BSTFA and then analysed by capillary GC and GC-MS. A suite of C26-C29 stenols and stanols and C30-C32 keto - alcohols were identified in the sediments. The thermal stability of the compounds in these sediments was studied by heating portions of the surface sediment in glass tubes fpr 16 hours at temperatures from 50℃ to 200℃.The C27 stanol/stenol ratio increased when temperatures went up to 175℃ , but the distribution of C30-C32 Keto - alcohols remained unaffected. At 200℃ most of the sterols and Keto - alcohols were destroyed. 相似文献
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5α and 5β cholestane, ergostane, stigmastane, hopane, etc., as well as 4-methyl-5β-stigmastane have been identified in an Tertiary oil shale sample from the oil field in North China, using cappillary gas-liquid chromatography-mass spectrometer. The resalts show that steroids occur in large amounts and a great variety, which thus provides an indication of their origination probably from higher plant debris. 相似文献
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Examination of solvent-extractable lipids in sediments from Beibu Gulf, South China Sea by capillary gas chromatography (GC) and capillary gas chromatography-mass spectrometry (GC-MS) resulted in the first identifications of β,γ-carotanes and their C19 to C31 homologs in the modern sediments from the China Seas. Distributional features of these ( mainly triterpenoid and steroid hydrocarbons) biomarkers are discussed and the possibility of using these compounds as indicators of source of materials, diagenesis and depositional conditions is explored. It was found that the biomarkers in this region are mixtures of allochthonous (terrigenous and / or crude oil leak or pollu -tion) and autochthonous (marine) organic components. The biomarkers have proved to be of value for understanding sedimentation . 相似文献
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云南腾冲盆地第四系硅藻土沉积物中的有机碳含量为0.5～1.51％,氯仿抽提物含量为835.1～3901.5ppm,抽提物中的饱和烃组份主要由正烷烃组成,其中以nC_(23)～nC_(33)为主,主峰为nC_(29)或nC_(31),奇数碳优势明显(OEP≥4),萜类化合物丰富,主要有C_(27)—17β(H)藿烷、C_(29)—17β(H)、21α(H)藿烷、C_(29)—17β(H)、21β(H)藿烷、C_(30)—17α(H)、21β(H)藿烷、C_(30)—17β(H)、21β(H)藿烷、C_(31)—17β(H),21β(H)藿烷,还有C_(27)—藿烯和C_(30)—藿烯等。此外,一般认为源于高等植物的降A环羽扇烷也非常丰富。 相似文献
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