甘肃窑街中侏罗世化石角质层有机质及其碳同位素组成与古环境的关系   总被引：3，自引：0，他引：3  

张成君  孙柏年  王云鹏  刘金钟  闫德飞 《西北地质》2004,37(2):42-47

通过对甘肃窑街中侏罗统窑街组化石银杏以及现代银杏角质层有机质组分和碳同位素组成分析．表明银杏角质层有较强的抗风化能力．化石和现代银杏角质层有机质烷烃和甾萜类化合物组成十分相似。可以通过角质层的碳同位素组成等参数进行古环境重建，结果表明中侏罗世早期古环境较为温湿．到了中期后古气候逐渐变得干旱少雨，后期降雨量又逐渐增加，温度升高，植被发育。  相似文献   

安塞油田长2油层成岩作用及其对储层物性的影响   总被引：7，自引：7，他引：7  

张金亮  梁杰  杜桂林 《西北地质》2004,37(4):50-58

安塞地区长2油层储层以中细粒长石砂岩为主，主要成岩矿物为绿泥石环边、方解石胶结物、石英和长石加大生长、伊利石、伊一蒙混层、钠长石和高岭石等。绿泥石环边的发育对原生粒间孔的保存起到有利的作用。石英加大级别达Ⅲ级，加大边含有丰富的有机包体，均一温度范围48．1～76．5℃，烃类进入储层的时间为早白垩世中期至晚白垩世。储层发育多种孔隙类型，面孔率平均为11．60％．主要类型有粒间孔、骨架颗粒溶孔和微裂缝等。残余粒间孔和骨架颗粒溶孔是本区长2储层的主要孔隙类型。根据成岩作用的矿物岩石学标志、有机质成熟度及古温度，将长2油层砂岩的成岩作用划分为3个成岩阶段：早成岩阶段、晚成岩阶段和表生成岩阶段。储层性质明显地受到沉积微相和成岩作用的影响，沉积物粒度较粗、厚度较大的分流河道储集物性明显优于各种粒度较细、厚度较薄的分流间席状砂体。  相似文献   

菌根真菌对土壤中有机污染物的修复研究   总被引：12，自引：0，他引：12  

刘世亮  骆永明  丁克强  李华  曹志洪  吴龙华  宋静 《地球科学进展》2004,19(2):197-203

菌根真菌是真菌与植物之间特殊的联合共生体，利用菌根真菌修复土壤，尤其是修复有机污染物污染的土壤，正成为一个崭新的研究方向。菌根真菌是土壤真菌的一种，但与土壤中放线菌和细菌等微生物相比，其对土壤中有机污染物具有更大的忍耐能力，并且能利用土壤中大多数持久性有机污染物作为碳源来获取能量。综述了近20年菌根真菌对土壤有机污染物降解研究，讨论了菌根真菌降解土壤有机污染物的可能机制，并探讨了从引入固氮菌、外源细菌两个方面对菌根调控以提高修复效果的可能性，为进一步研究菌根真菌生物降解土壤中持久性有机污染物、利用菌根植物修复有机污染土壤提供信息。  相似文献   

Size-Resolved Aerosol Characterization for a Polluted Episode at the IfT Research Station Melpitz in Autumn 1997     

A. Plewka  T. Gnauk  E. Brüggemann  C. Neusüss  H. Herrmann 《Journal of Atmospheric Chemistry》2004,48(2):131-156

Inorganic ions, organic carbon (OC), elemental carbon (EC) and a variety of organic single species in airborne particles have been determined at the research station of the Leibniz – Institut für Troposphärenforschung (IfT) in Melpitz (Germany) in autumn 1997.Samples of eight selected measurement events were divided in two groups in order to investigate differences in the chemical composition of particles originating from southwesterly (SW – developed EU countries) or from easterly directions (E – less developed eastern countries). Differences between these two groups were tested statistically by Student's t-test.Five stage cascade impactor samples show nitrate as most abundant in the accumulation mode in the SW group. EC and sulphate show the most abundant mass fractions in the E group. That can be considered as a consequence of domestic coal heating and coal-fired power plant emissions in the region of westerly Poland, northern Czech Republic and easterly Germany. Higher nitrate concentrations in the SW group can be explained by stronger NO _x emissions caused by the leeward plume of the conurbation of Leipzig, as well as by the still higher traffic density in western Germany.The methane sulphonic acid (MSA) mass fraction was higher for SW air masses in accumulation mode particles, probably indicating marine origin. Succinic acid also showed higher mass fractions for the SW group. This could be caused by primary emission in automobile exhaust gases and photochemical formation during transport from SW. Indeed, during SW sampling, solar radiation intensity was higher than during E sampling.The observed differences in the particle composition are an expression of the still existing technology gradient in Europe. Future campaigns could show the development to a joint economy with smaller differences in anthropogenic emissions.  相似文献   

轮南油田原油中三甲基苯基类异戊二烯化合物的检出及其意义     

卢鸿孙永革  彭平安 《高校地质学报》2004,10(2):283-289

轮南油田不同时代储层原油中检出了丰富的三甲基苯基类异戊二烯化合物。该类化合物被普遍认为是来自于高盐度和强还原水体沉积环境中绿硫菌体内的类胡萝卜素的特征性生物标志化合物。该类化合物的检出对轮南油田烃源岩研究具有重要的指示意义，暗示了具有分层水体或高盐度的强还原环境下发育的优势烃源岩，对该区烃类的主力生烃贡献不容忽视。基于C15-3，4，5-三甲基苯基类异戊二烯异构体在轮南油田原油中的分布规律，及C15-3，4，5／C13-2，3，6-比值与Pr／Ph，Ga／C31H和Ts／Tm等常规地球化学参数的对比，说明具有生源意义、能够指示沉积相特征的三甲基苯基类异戊二烯化合物分布，在一定程度上也受烃类热演化程度的影响。  相似文献   

长江下游湖泊水体中有色可溶性物质的生物光学模式   总被引：8，自引：0，他引：8  

杨顶田  陈伟民  曹文熙 《遥感学报》2005,9(4):387-392

通过2001年7月至2002年12月对长江下游的太湖、巢湖、龙感湖水体中有色可溶性物质的光吸收及荧光特性的研究发现:在对S值进行测定时,所测得的S值为0·0046nm-1(SD=0·0015,n=284),与文献中的0·014nm-1相差较大,可能是由于高浓度的DOC受到激发后在蓝光波段释放较强荧光的缘故;荧光强度与水体中DOC含量之间的关系较难确定,DOC与350nm光吸收(a(350nm))之间呈现较强的线性关系,其相关值达到0·673(n=284);荧光强度与a(350nm)之间线性关系相对较弱,其相关值为0·497(n=214);从上面的结果可以看出,用荧光的方法直接测定DOC含量的可信度相对较低,而直接利用光吸收测定的可信度较高。  相似文献   

Uptake and depuration of PAHs and chlorinated pesticides by semi-permeable membrane devices (SPMDs) and green-lipped mussels (Perna viridis)     

Bruce J. Richardson  Edmund S.-C. Tse  Sharon B. De Luca-Abbott  Michael Martin  Paul K.S. Lam 《Marine pollution bulletin》2005,51(8-12):975

Semi-batch seawater experiments were conducted to follow the uptake and release of selected PAHs (anthracene, fluorathene, pyrene and B[a]P) and organochlorine pesticides (α-HCH, aldrin, dieldrin, p,p′-DDT) in semi-permeable membrane devices (SPMDs) and green-lipped mussels (Perna viridis). Mathematical models were applied to describe the uptake and elimination curves of the contaminants for SPMDs, and kinetic parameters, such as uptake rate constants, and equilibrium triolein/water partitioning coefficients were calculated. SPMD data showed a good fit to estimate rate constant and partition coefficient equations, but only those contaminants which partitioned mainly in the dissolved phase (α-HCH and dieldrin) were well explained for mussels. Poor conformity of the other contaminants indicated mussels uptake by routes other than diffusion, such as ingestion of algae. An apparent equilibrium state was only noted for α-HCH in mussels. Aldrin was not detected in mussels in the first few days of exposure, indicating potential metabolism of this compound. B[a]P was not detected in the triolein of SPMDs, which suggests that the membrane may act as a reservoir. Loss of spiked B[a]P from the triolein was evident in a depuration experiment, which may indicate transfer to the membrane. Rate constants for mussels were higher than those for SPMDs, but the reverse was true for partition coefficients. Overall, mussels and SPMDs had similar uptake rates for all compounds in this study, excluding p,p′-DDT and dieldrin. Contaminant elimination took place more rapidly in mussels, implying that SPMDs are better candidates for detecting episodic discharge of organic contaminants.  相似文献   

Molecular cloning and mRNA expression of cytochrome P4501A1 and 1A2 in the liver of common minke whales (Balaenoptera acutorostrata)     

Satoko Niimi  Michio X. Watanabe  Eun-Young Kim  Hisato Iwata  Genta Yasunaga  Yoshihiro Fujise  Shinsuke Tanabe 《Marine pollution bulletin》2005,51(8-12):784

This study presents full-length cDNA sequences of CYP1A1 and 1A2, in common minke whale (Balaenoptera acutorostrata) from the North Pacific. Both CYP1A1 and CYP1A2 cDNAs had an open reading frame of 516 amino acid residues, and predicted molecular masses were 58.3 kDa and 58.1 kDa, respectively. The deduced full-length amino acid sequence of CYP1A1 revealed higher identities with those of sheep (86%) and pig (87%), and that of CYP1A2 was most closely related to human (82%) and monkey CYP1A2 (82%) among species from which CYP1A2 has been isolated so far. Differences in certain conserved and functional amino acid residues of CYP1A1 and 1A2 between common minke whale and other mammalian species indicate the possibility of their specific metabolic function. Concentrations of organochlorine compounds (OCs) including PCBs and DDTs analyzed in common minke whale liver showed no significant correlation with hepatic mRNA expression levels of CYP1A1 and CYP1A2, indicating no induction of these enzymes by such OCs.  相似文献   

Persistent organic pollutants in remote freshwater ecosystems   总被引：3，自引：0，他引：3  

Pilar Fernández  Guillem Carrera  Joan O. Grimalt 《Aquatic Sciences - Research Across Boundaries》2005,67(3):263-273

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Export of dissolved organic carbon from agricultural streams in Illinois, USA   总被引：1，自引：0，他引：1  

Todd V. Royer  Mark B. David 《Aquatic Sciences - Research Across Boundaries》2005,67(4):465-471

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