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1.
生物降解原油中吡咯氮化合物组成的变化 总被引：1，自引：0，他引：1
渤海海域地区近50个原油样品中性氮组分的GC／MS定量分析资料表明,油藏中的生物降解作用对原油的吡咯氮化合物含量和分布有明显影响。经与同源未降解原油比较,各种烷基咔唑和苯并咔唑在3。4级中轻度降解油中就出现明显降解迹象,随生物降解程度增高其含量逐渐减少,在6—8级严重降解油中它们的总含量降低到原有的五分之一左右。在3—4级中轻度降解油中,裸露型甲基咔唑异构体更容易被微生物侵袭而代谢,抗生物降解能力按1-甲基咔唑〉4-甲基咔唑〉2-、3-甲基咔唑顺序递减;当降解程度更高时,这些化合物降解速率相当,1-／4-MCA等比值相对稳定。低-中等降解阶段,不同类型二甲基咔唑异构体的抗生物降解能力也存在明显差异性,呈屏蔽型〉半屏蔽型〉裸露型降低;在生物降解水平进一步增高时,这些异构体之间的相对含量变化不大。生物降解作用对苯并咔唑系列化合物分布的影响具有不确定性,且随降解程度的增加变得更为显著,降解油中【a】／[c】苯并咔唑比值或增高或降低。生物降解原油中吡咯氮化合物的组成变化,使降解油的二次运移示踪面临新的问题。 相似文献
2.
Cl—PMBP萃淋树脂分离测定岩石中微量稀土、钪和钍 总被引：1，自引：0，他引：1
PMBP(1-苯基-3-甲基-4-苯甲酰基吡唑酮-5)是一种β-二酮类的螯合剂,pKa=4.04,有较高的离解度,易与金属离子生成络合物。其烯醇式结构中有一个能被金属离子取代的氢原子和一个酮基结合成六元环。如下: N=C—CH_3 相似文献
3.
塔里木盆地群4井原油吡咯类含氮化合物地球化学研究 总被引：27，自引：7，他引：27
在塔里木盆地群４井原油中成功地分离并检测出丰富的吡咯类含氮化合物-链基咔唑类，而链基苯并咔唑和链基二苯并咔唑则未被发现。链基咔唑中以二甲基咔唑、C3-咔唑和C4-咔唑为主。在甲基咔唑和二甲基咔唑中又鉴别出多个异构体。甲基咔唑中G2 G3含量相当，而二甲基咔唑中G3占优势。在我国，原油含氮化合物研究刚刚起步。实践证明，该类化合物是研究油气运移的可靠的、专属性强的标志化合物。通过本项研究，我们认为群４井原油已经历了长距离的运移。 相似文献
4.
通过对盐生杜氏藻的热模拟成烃研究,发现其热解产物中含有丰富的咔唑系列化合物,它包括咔唑（CZ）、甲基咔唑（M CZ）、二甲基咔唑（DM CZ）、三甲基咔唑（TM CZ）、四甲基咔唑（TeM CZ）、五甲基咔唑（PM CZ）和六甲基咔唑（HM CZ）。并且在300℃热模拟产物中咔唑系列化合物含量较高,在芳烃馏分中相对含量为30.97％,350℃时产出较低,为15.44％,而250℃时未检出此类化合物。这一方面表明嗜盐杜氏藻很可能是原油和烃源岩中咔唑类化合物的主要母源之一,另一方面表明高盐环境下这种以杜氏藻为主要生烃母质的原油可能富集咔唑类化合物,这为该环境下油源对比提供了有力依据。 相似文献
5.
准噶尔盆地北三台地区湖相原油咔唑类化合物的地球化学特征 总被引：3，自引：3，他引：3
准噶尔盆地北三台地区北 82井、北 83井和沙 10 8井湖相原油咔唑类化合物的分布特征表明,油气运移作用是影响该区原油中咔唑类化合物分布的重要因素。沿油气运移方面,咔唑类化合物具有明显的分馏效应。总的趋势是原油中咔唑类化合物、高分子量的烷基咔唑化合物和苯并咔唑化合物的含量逐渐减少,低分子量咔唑和甲基咔唑,以及具屏蔽效应的二甲基咔唑和苯并 [a]咔唑异构体的相对含量则逐渐增加。利用咔唑类化合物的分馏效应,可有效地指示油气运移方向。 相似文献
6.
中性含氮化合物的演化及地化意义 总被引：13，自引：0，他引：13
通过对生油岩样品中的中性氮系列化合物含量和组成变化的系统研究。指出含氮化合物的热演化规律和形成机制。含氮化合物是沉积有机质成岩演化的产物。其含量和组成明显受控于有机质成熟度；认为1-/4-甲基咔唑，苯并[a]咔唑/苯并[c]咔唑等比值可作为成熟度参数。 相似文献
7.
塔里木轮南地区原油沥青质的分子结构及其初步应用:热解、甲基化-热解和RICO研究 总被引：3，自引：3，他引：0
利用瞬间热解、甲基化-热解和钌离子催化氧化(RICO)降解技术研究了塔里木盆地轮南地区原油沥青质的分子结构,并对其在石油地球化学研究中的指示意义进行了讨论.轮南地区原油沥青质分子中的取代官能团以烷基侧链为主,烷基桥次之,另外还有少量的烷基-环己烷、支链烷烃和苯系物,这些化合物可能大都以C-C键结合到缩合芳环体系上;沥青质分子中的芳环体系大多数可能是萘或菲类型的芳香结构,高度缩合的芳香结构可能较少.轮南地区不同构造带原油沥青质热解产物的一致性指示它们可能来自沉积环境相同的母源.沥青质的分子结构表明,其母源可能主要来自浮游藻类的类脂物.热解产物中较高含量的1,2,3,4-四甲基-苯和2,6-二甲基、2,6,10-三甲基烷烃类化合物的检出表明其母质可能形成于较强的还原环境.沥青质热解产物中姥鲛-1-烯的相对含量较低,RICO产物中一元脂肪酸远高于二元脂肪酸,指示该区原油具有较高的成熟度.部分脂肪酸类化合物通过酯键连接在沥青质分子中,可能反映了原油在储层中经历了生物降解等后生作用. 相似文献
8.
《矿物岩石地球化学通报》2017,(4)
为探讨塔里木盆地原油类型和油源问题,运用色谱-同位素质谱分析技术,分析了该盆地塔中、塔北、塔东与库车地区的典型原油轻烃单体烃碳同位素组成。结果表明,不同结构轻烃化合物中,支链烷烃与环己烷系列比环戊烷系列更具明显的成因判识意义。2-甲基环戊烷2 mC_5、3-甲基环戊烷3 mC_5、3-甲基环己烷3 mC_6、环己烷CYC6与甲基环己烷mCYC_6等化合物的δ~(13)C在煤成油最高,δ~(13)C大于-21‰;湖相油次之,δ~(13)C位于-25‰~-22‰之间;再次之为寒武系-下奥陶统海相原油,δ~(13)C位于-27‰~-21‰之间,最轻的为上奥陶统海相原油,δ~(13)C小于-28‰。其碳同位素值可以较好的判别该盆地寒武系-下奥陶统海相油、上奥陶统海相油、湖相油与煤成油。优选的8个特征化合物碳同位素可以作为原油成因类型的划分标志,尤其是2-甲基环戊烷2 mC_5、3-甲基环戊烷3 mC_5、3-甲基环己烷3 mC_6、环己烷CYC6与甲基环己烷mCYC_6等化合物。特征轻烃化合物的碳同位素组成可成为不同成因原油的划分标志。 相似文献
9.
分析和研究了69个样品的咔唑类含氮化合物数据,认为惠民凹陷临南地区沙三段咔唑类含氮化合物中的咔唑、甲基咔唑、二甲基咔唑及苯并咔唑等.与埋藏深度、成熟度和沉积环境之间关系密切.因此今后研究过程中可以考虑部分咔唑类含氮化合物的含量和比值作为成熟度指标和指相标志. 相似文献
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11.
<正>Kailu Basin in which the Western Lujiapu Depression is located is a typical continental rift basin.Biomarker parameters of the oils indicate that depositional facies and environments vary between the Bao 1 and Bao 14 fault blocks with a higher saline environment in the Bao 1 fault block, but such difference has no significant impact on carbazole abundance and distribution.Maturity and migration distance are the main controls on carbazole abundance and distribution in the Western Lujiapu Depression.The commonly used migration indices,such as ratios of nitrogen shield isomers to nitrogen exposed isomers(1-/4-methylcarbazole ratio,1,8-/2,4-dimethylcarbazole(DMC) ratio and half-shield/exposed-DMC ratio),absolute concentrations of alkylated carbazoles and BC ratio(=benzo [a]carbazole/(benzo[a]carbazole+benzo[c]carbazole)) increase at the low mature range and decrease at a higher mature range with increasing maturity.At relatively low maturity stage(Rc0.77%), maturation has reversal effects with migration on the ratios of nitrogen shield isomers to nitrogen exposed isomers,which may cover migration influence and makes these parameters fail to indicate migration effects.Valid migration indicators at this maturity stage are concentrations of alkylated carbazoles and BC ratios,which can provide ideal tools for migration direction assessment even within short migration distance.Maturity effects should be taken into account when carbazole compounds are applied to indicate migration direction,and at different maturity stages,these commonly used parameters have different validity in tracing migration direction.Coupled with our previous study in the Eastern Lujiapu Depression,a conceptual model of the variation of nitrogen migration indices can be established for terrestrial rifted basins,that is,strong fractionation lateral migration model through sandy beds,weak fractionation vertical migration model along faults,and maturity impacts on migration assessment. 相似文献
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13.
CHEN Chuanping LIU Jianping GU Xu and ZHOU Sumin School of Life Science Chemical Engineering Huaiyin Institute of Technology Huai’an China School of Chemistry Huazhong Normal University Wuhan China 《中国地球化学学报》2008,27(2):135-139
The distance between 4-H and adjacent H on the substitutional benzene ring in benzo[c]carbazole was calculated in terms of molecular structure parameters. The result showed that the distance is shorter than the sum of van der Vaals＇ radii of two hydrogen atoms. This means that there is a steric hinderance between them. This effect will make the bond angle stretch and the bond length extend, or cause the molecule to distort, thus making benzo[c]carbazoles become unstable in thermodynamics. On the contrary there is no such effect for benzo[a]carbazoles. This conclusion has been confirmed by the result of calculation of the distance between the same two atoms with software GaussView. So the skeleton of benzo[c]carbazoles in sediments may be breached or isomerized with increasing maturity. It is consistent with the decrease of the ratio of benzo[c]carbazole to benzo[a]carbazole in hydrocarbon migration, suggesting that [c]/[a] not only changes with the distance of migration, but also may be influenced by maturity. 相似文献
14.
Role of hydrogen peroxide and hydroxyl radical in pyrite oxidation by molecular oxygen 总被引：3，自引：0，他引：3
Martin A.A. Schoonen Andrea D. Harrington Daniel R. Strongin 《Geochimica et cosmochimica acta》2010,74(17):4971-3773
Hydrogen peroxide and hydroxyl radical are readily formed during the oxidation of pyrite with molecular oxygen over a wide range of pH conditions. However, pretreatment of the pyrite surface influences how much of the intermediates are formed and their fate. Acid-washed pyrite produces significant amounts of hydrogen peroxide and hydroxyl radical when suspended in air-saturated water. However, the hydrogen peroxide concentration shows an exponential decrease with time. Suspensions made with partially oxidized pyrite yield significantly lower amounts of hydrogen peroxide product. The presence of Fe(III)-oxide or Fe(III)-hydroxide patches facilitates the conversion of hydrogen peroxide to oxygen and water. Hence, the degree to which a pyrite surface is covered with patches of Fe(III)-oxide or Fe(III)-hydroxide patches is an important control on the concentration of hydrogen peroxide in solution.Hydrogen peroxide appears to be an important intermediate in the four-electron transfer from pyrite to molecular oxygen. Addition of catalase, an enzyme that decomposes hydrogen peroxide to water and molecular oxygen, to a pyrite suspension reduces the oxidation rate by 40%. By contrast, hydroxyl radical does not appear to play a significant role in the oxidation mechanism. It is estimated on the basis of a molecular oxygen and sulfate mass balance that 5-6% of the molecular oxygen is consumed without forming sulfate. 相似文献
15.
A powder neutron diffraction study of ussingite, Na2AlSi3O8(OH), over the temperature range 4–850 K has been undertaken. The strong hydrogen bond that exists in this mineral has been accurately determined with the O–H distance at 1.070(8) Å and an O(donor)–O(acceptor) separation of 2.481(5) Å at 4 K, The distribution of hydrogen along the O–O direction remains asymmetric between 4 and 850 K with the H atom being fully ordered at a single site, rather than partially disordered over two sites of a double-potential well, as in serandite. A gradual increase in the bonded O–H distance at higher temperatures is observed, indicative of a broadening of the potential well in which the hydrogen atom is sited. Below 50 K, the material shows negative thermal expansion, likely to be associated with reduced bending motion of the O–H bond. 相似文献
16.
1987年8月王宁等报道具有八次对称轴准晶的高分辨图象,呈现出正八边形相嵌的图案。本文认为从配位多面体理论上对八次对称存在的可能性加以研究是有必要的,为此提出了具有十次配位的等腰三角十六面体和一系列带帽反棱柱,精确地求出了这些十六面体的顶点间的夹角、棱长和晶面法线与四次轴间的夹角等几何参数,作为应用对于Cr—V—Ni—Si八次对称准晶,设Ni原子（简称原子A）位于多面体中心,而V,Cr,Si原子（简称原子B）位于顶点上,原子A和B之半径分别为1.24（?）和1.32（?）,间隙0≤（?）（?）≤0.6（?）.则:（1）若原子A和B按等腰三角十六面体配位且A,B的键长为（2.56+δ）（?）,则原子B间的键长为1.08（2.56+δ）（?）或1.29（2.56+δ）（?）;（2）若原子A和B按带帽反棱柱配位且呈“紧密堆积”,则原子A和B之间的键长为（2.56+δ）（?）或（2.56+δ）(0.511+（0.261+[0.08/（2.56+δ）]n）1/2（?） 相似文献
17.
The mineral ussingite, Na2AlSi3O8(OH), an interrupted tectosilicate, has strong hydrogen bonding between OH and the other nonbridging oxygen atom in the structure. Infrared spectra contain a strongly polarized, very broad OH-stretching band with an ill-defined maximum between 1500 and 1800 cm–1, and a possible OH librational bending mode at 1295 cm–1. The IR spectra confirm the orientation of the OH vector within the triclinic unit cell as determined from X-ray refinement (Rossi et al. 1974). There are three distinct bands in the 1H NMR spectrum of ussingite: a predominant band at 13.5 ppm (TMS) representing 90% of the structural hydrogen, a second band at 15.9 ppm corresponding to 8% of the protons, and a third band at 11.0 ppm accounting for the remaining 2% of structural hydrogen. From the correlation between hydrogen bond length and 1H NMR chemical shift (Sternberg and Brunner 1994), the predominant hydrogen bond length (H...O) was calculated to be 1.49 Å, in comparison to the hydrogen bond length determined from X-ray refinement (1.54 Å). The population of protons at 15.9 ppm is consistent with 5–8% Al–Si disorder. Although the ussingite crystal structure and composition are similar to those of low albite, the bonding environment of OH in low albite and other feldspars, as characterized through IR and 1H NMR, is fundamentally different from the strong hydrogen bonding found in ussingite. 相似文献
18.
The methylation index (MBT or MBT′) of branched glycerol dialkyl glycerol tetraethers (brGDGTs) in soils along altitudinal transects of some mountains, e.g. Mount (Mt.) Shennongjia and Mt. Gongga, exhibited no correlation with altitude or mean annual air temperature (MAT) alone. However, a significant correlation between MBT′, cyclization ratio (CBT) of brGDGTs and MAT for each transect could still be found. To investigate the reason, we reanalyzed the brGDGTs in soils from Mt. Shennongjia using an improved liquid chromatography method and examined whether the newly described 6-methyl brGDGTs were the main cause of the large scatter in the correlation between MBT′ and MAT. In contrast to MBT′, the MBT′5ME, based on 5-methyl brGDGTs alone, correlated significantly with MAT (R2 0.89, p < 0.001) but had no relationship with soil pH. However, MBT′6ME, based only on 6-methyl brGDGTs, was strongly dependent on soil pH. This suggests that pH dependent 6-methyl brGDGTs introduce large scatter in the correlation between MBT′ and MAT, which is likely to mechanistically explain the poor relationship between MBT′ and MAT, yet good correlation between MBT′, pH and MAT. A series of indices derived from 6-methyl brGDGTs, including IRIIIa′ and IRIIa′ (isomer ratio of structures IIIa′ and IIa′, respectively), correlated with soil pH and can be used as new paleo pH indicators to supplement the classic CBT proxy. The tetramethylated brGDGTs with 0–1 cyclopentyl rings (Ia and Ib) were found to comprise unknown isomers, whose abundances also appear to increase with soil pH. A further optimized liquid chromatography method is needed to quantify these new isomers more accurately and to determine the environmental controls on them. 相似文献
19.
H. Kagi J. B. Parise H. Cho G. R. Rossman J. S. Loveday 《Physics and Chemistry of Minerals》2000,27(4):225-233
Neutron powder diffraction data of phase A (Mg7Si2O8(OH)6) were collected at ambient pressure and 3.2?GPa (calculated from the compressibility of phase A) from the deuterated compound, and the structure was refined using the Rietveld method. The derived crystal structure implies that hydrogen atoms occupy two distinct sites in phase A, both forming hydrogen bonds of different lengths with the same oxygen atom. This picture is supported by IR spectra, which exhibit two absorption bands at 3400 and 3513?cm?1 corresponding to OH stretching vibrations, and proton NMR spectra, which display two peaks with equal intensities and isotropic chemical shifts of 3.7 and 5?ppm. The D-D distance [D(1)-D(2) distance] at ambient pressure was found to be 2.09?±?0.02?Å from the neutron diffraction data and 2.09?±?0.05?Å from the NMR spectra. At 3.2?GPa, there is no statistically significant increase in the O-D interatomic distance while the hydrogen bonding interaction D···O appears to increase for one of the hydrogen sites, D(1), which has the stronger hydrogen bonding interaction compared with the other hydrogen, D(2), at ambient pressure. The O-D bond valences, determined indirectly from the D···O distances were 0.86 and 0.91 at ambient pressure, and 0.83 and 0.90?at 3.2?GPa, for D(1) and D(2), respectively. 相似文献
20.
The sterol analysis of six hydrocarbon seep mussels (mytilid II and mytilid Ib) from the Alaminos Canyon in the Gulf of Mexico is reported. The sterol composition of the mussel-symbiotic bacteria complex reflects a preponderant synthesis of 4α-methyl sterols (seep mytilid II), and a predominant biosynthesis of 4-desmethyl sterols with some amounts of 4α-methyl sterols (seep mytilid Ib). This suggests a methane-based symbiotic relationship between the mussels and methanotrophic bacteria. It also suggests that the biosynthesis of sterols in the mussel-bacteria complex is completed to the level of cholest-5-en-3ß-ol (mytilid II) or 5α-cholestan-3ß-ol (mytilid Ib). 相似文献