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101.
贵州红枫湖沉积物有机质的酶及微生物降解 总被引:8,自引:1,他引:8
文章通过DNA、α-葡萄糖苷酶和硫酸盐还原菌等的变化,研究了贵州红枫湖沉积物中有机质的酶及微生物降解.有机质在微生物及其分泌的胞外酶的作用下被降解,在沉积物深度11cm以下被降解到相对较低的含量.DNA的分布表明表层9cm的沉积物深度内微生物的活动较为强烈,是微生物降解有机质的主要位置.α-葡萄糖苷酶在悬浮层含量最高,达0.75μmol/min*g干沉积物,提示有机质中的淀粉和糖原等物质在悬浮层降解较为激烈,被大量分解;随着沉积物深度的增加α-葡萄糖苷酶活性减弱,在有机质降解明显开始变缓的11cm沉积物中,α-葡萄糖苷酶活性已降低到0.17μmol/ming干沉积物.分子生物学的研究表明红枫湖沉积物表层7cm是硫酸盐还原菌的主要分布位置,结合有机质和SO2-4含量的研究结果,提示红枫湖沉积物中SO2-4不可能成为有机质氧化的主要电子受体,硫酸盐还原的限制因素也不是有机质供应. 相似文献
102.
原子荧光光谱法测定化探样品时有机质对As,Sb,Bi的干扰 总被引:1,自引:0,他引:1
通过研究黑龙江省森林沼泽景观区有机水系沉积物(泥炭)、土壤中As,Sb,Bi的测定结果,发现样品中的有机质对王水消解氢化物原子荧光法测定上述元素存在极大的干扰,提出采用低温(<450℃)灰化处理可完全消除干扰。对比研究还发现,过去森林沼泽景观区的区域化探扫面资料中的As,Sb,Bi数据存在问题,应专门对其进行评价研究。 相似文献
103.
104.
105.
Abstract Spinel lherzolite is a minor component of the deep-seated xenolith suite in the Oki-Dogo alkaline basalts, whereas other types of ultramafic (e.g. pyroxenite and dunite) and mafic (e.g. granulite and gabbro) xenoliths are abundant. All spinel lherzolite xenoliths have spinel with a low Cr number (Cr#; < 0.26). They are anhydrous and are free of modal metasomatism. Their mineral assemblages and microtextures, combined with the high NiO content in olivine, suggest that they are of residual origin. But the Mg numbers of silicate minerals are lower (e.g. down to Fo86 ) in some spinel lherzolites than in typical upper mantle residual peridotites. The clinopyroxene in the spinel lherzolite shows U-shaped chondrite-normalized rare-earth element (REE) patterns. The abundance of Fe-rich ultramafic and mafic cumulate xenoliths in Oki-Dogo alkali basalts suggests that the later formation of those Fe-rich cumulates from alkaline magma was the cause of Fe- and light REE (LREE)-enrichment in residual peridotite. The similar REE patterns are observed in spinel peridotite xenoliths from Kurose and also in those from the South-west Japan arc, which are non-metasomatized in terms of major-element chemistry (e.g. Fo > 89), and are rarely associated with Fe-rich cumulus mafic and ultramafic xenoliths. This indicates that the LREE-enrichment in mantle rocks has been more prominent and prevalent than Fe and other major-element enrichment during the metasomatism. 相似文献
106.
地史过程中烃源岩有机质丰度和生烃潜力变化的模拟计算 总被引:17,自引:0,他引:17
在同时考察源岩中有机质因生、排烃而损失和无机质因成岩作用而失重的基础上,模拟计算了地史过程中,随有机质类型、初始有机质丰度、成熟度及排烃效率的改变,烃源岩有机质丰度和生烃潜力的变化,探讨了有机碳恢复系数及生烃潜力损失率的可能变化范围。结果表明,地史过程中,有机质生烃潜力和有机质丰度的变化主要取决于源岩的生、排烃效率,对性质偏差的有机质,有机质的实测丰度随演化程度的增高不降反升;而对位于高成熟阶段的优质有机质,有机碳的恢复系数可达2以上;随有机质类型变好和成熟度升高,生烃潜力损失率增高;一般情况下,有机质生烃潜力的恢复幅度比有机质丰度的恢复大得多。 相似文献
107.
Michel Mbina Mounguengui François Baudin Jacques Lang Olivier Jocktane 《Comptes Rendus Geoscience》2003,335(3):327-334
The Interior Basin of Gabon, created during the break-up between South America and Africa, displays thick Neoproterozoic to Aptian p.p. fluvio-lacustrine deposits overlain by Aptian to Albian marine facies. Rock–Eval analyses from outcrop and drillhole samples show high content in organic matter (up to 25%) related to types I and II. These intervals are encountered within Permian, Neocomian–Barremian as well as Aptian siliciclastic succession. They constitute fairly good to excellent potential petroleum source rocks, which are most probably at the origin of oil indices recognized both in drillholes and in surface. 相似文献
108.
R. G. Derwent W. J. Collins M. E. Jenkin C. E. Johnson D. S. Stevenson 《Journal of Atmospheric Chemistry》2003,44(1):57-95
A global 3-D Lagrangian chemistry-transport model STOCHEM is used to describe the tropospheric distributions of four components of the secondary atmospheric aerosol: nitrate, sulphate, ammonium and organic compounds. The model describes the detailed chemistry of the formation of the acid precursors from the oxidation of SO2, DMS, NOx, NH3 and terpenes and their uptake into the aerosol. Model results are compared in some detail with the available surface observations. Comparisons are made between the global budgets and burdens found in other modelling studies. The global distributions of the total mass of secondary aerosols have been estimated for the pre-industrial, present day and 2030 emissions and large changes have been estimated in the mass fractions of the different secondary aerosol components. 相似文献
109.
临兴区块上古生界储集层为致密砂岩,裂缝发育特征及对致密气富集影响尚不清楚,一定程度上制约了甜点区预测。
根据岩心、露头、薄片及测井资料,分析了研究区裂缝发育特征,探讨了裂缝对致密砂岩气富集的影响。临兴区块上古生界主
要发育高角度缝,其次为中低角度缝及水平缝,微观上根据裂缝与矿物颗粒的相对位置关系,可识别出粒内缝、粒缘缝和穿粒
缝,其中粒缘缝最为发育。受塑性泥岩阻挡,裂缝垂向延伸较差,一般延伸1~2 m后消失于泥岩层中,受燕山期北西—南东向
地应力影响,裂缝走向多为北东—南西向,裂缝密度一般2~5条/m。裂缝可改善储集空间、提高油气充注效率,储层裂缝发育
区渗透率可增大1~2个数量级,含气饱和度高,此外,研究区裂缝是油气垂向运移的有效通道,影响着石盒子组及石千峰组致
密气的富集,在后期的勘探开发过程中应充分寻找裂缝发育区,并通过进一步压裂获得高产。 相似文献
110.
Organic pollutants associated with macromolecular soil organic matter: Mode of binding 总被引:2,自引:0,他引:2
H. H. Richnow R. Seifert J. Hefter M. Link W. Francke G. Schaefer W. Michaelis 《Organic Geochemistry》1997,26(11-12)
A study of ether-linked moieties in macromolecular bound residues of polycyclic aromatic hydrocarbons (PAH) generated in bioremediation experiments was performed using high temperature hydrolysis degradation with subsequent analysis of the products by GC-MS. This hydrolysis reaction was specifically designed to cleave ether bonds including relatively stable diarylether structures. Among the reaction products, aromatic alcohols representing typical microbiologically derived metabolites of PAH were found in addition to natural compounds. Thus, parts of the bound residues appeared to be linked within the macromolecular material by ether bonds. Model experiments with an oxidoreductase enzyme and aromatic alcohols indicate the formation of these ether bonds to be an enzyme-catalysed process. 相似文献