10 resultados para Ivan IV, Czar of Russia, 1530-1584.

em Chinese Academy of Sciences Institutional Repositories Grid Portal


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A new crystal modification induced by strain and denoted as form II exists alongside the dominant form I structure in the uniaxially oriented poly(ether ether ketone) (PEEK) and the related polymers. The crystal structure of form II for PEEK is also found to possess a two-chain orthorhombic packing with unit cell parameters of a equal to 0.475 nm, b equal to 1.060 nm, and c equal to 1.086 nm. More extended and flattened chain conformation of form II relative to that of form I is expected to account for an 8% increase in c-axis dimension, which is attributed to the extensional deformation fixed in situ through strain-induced crystallization during uniaxial drawing. Annealing experiments suggest that form II is thermodynamically metastable and can be transformed into more stable form I by chain relaxation and reorganization at elevated temperature without external tension. This strain-induced polymorphism exists universally in the poly(aryl ether ketone) family. (C) 1999 John Wiley & Sons, Inc.

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在现代的陆地植被当中,石松类为草本植物,在植物界中属于高等植物的低等部分。然而在陆地植物起源和发展演化的早期阶段,石松类是陆地植被的重要成分。石炭纪时期石松类处于最繁盛时期,多生长成为高大乔木,形成森林,是陆地植被的优势类群,也是主要的成煤植物。作为演化历史最长的陆地植物之一,石松类在泥盆纪时期就广泛分布于世界各地,泥盆纪成为石松类演化发展的一个非常重要的时期。研究泥盆纪石松类对认识石松类的起源和发展有重要意义。 本论文是作者在博士期间多个工作之中的两个内容,对采自俄罗斯远东地区的晚泥盆世石松类Haskinsia标本以及采自湖南醴陵的晚泥盆世石松类Lilingostrobus longifolius标本进行了研究。 我们在俄罗斯远东地区的标本中发现了具有三角形叶片的简单叶。泥盆纪石松类Haskinsia属的最典型特征就是其叶由叶柄和三角形或戟形的叶片组成。综合标本的其它特征我们将这些标本归入Haskinsia colophylla这个种中。俄罗斯学者曾在与我们相同的采集地点采集了相似的标本并将其命名为Pseudolepidodendron igrischense,经过仔细对比后我们认为俄罗斯学者的标本也应归并入H. colophylla。同时根据Haskinsia属分布于早泥盆世晚期至晚泥盆世早期的特点,我们对采集地点的地层时代进行了修订,认为其地层时代要比俄罗斯学者认为的晚泥盆世至早石炭世要早。 我们在标本中还首次发现了Haskinsia colophylla这个种的孢子囊。在此之前,Haskinsia 属内的H. colophylla和H. sagittata由于具有相类似的叶而被认为可能是同一个种。由于仅在H. sagittata中发现了孢子囊(椭圆形/卵形)而没有发现H. colophylla的生殖结构,无法确切地区分这两个种。我们在标本中发现了着生于孢子叶腹面的圆形孢子囊。这一发现使我们确认了H. colophylla与H. sagittata的区别,这两个种都是有效种。 我们还对采自湖南醴陵望仙桥水库剖面晚泥盆统岳麓山组地层的部分石松类标本进行了研究。该石松类被命名为Lilingostrobus longifolius。它为木本石松类,茎为二岐分枝,叶在茎上螺旋形排列,叶为长披针形,具有中脉。孢子叶球顶生,呈长锥形,顶端钝圆,孢子叶在孢子叶球上呈紧密的螺旋形排列,每轮约6-8枚。孢子叶分化为孢子叶梗和孢子叶片。孢子叶梗与穗轴近垂直,水平向外延伸后向上弯曲成孢子叶片,叶片至少长45mm,超过孢子叶球长度的一半,孢子叶片与营养叶同型。孢子囊长椭圆形,着生于孢子叶梗的上面。Lilingostrobus longifolius为异型孢子叶球,分为大孢子叶球和小孢子叶球。茎轴具有外始式的初生木质部以及呈放射状的次生木质部。管胞次生壁具有梯纹加厚,加厚的横棒之间有纵向的条状物,即“威廉姆森结构”。Lilingostrobus longifolius具有孢子叶分化明显的孢子叶球因而被归入广义的水韭目。根据其管胞类型和孢子叶球特点,我们认为其可能与Sublepidodendron属亲缘关系较近。 通过对Lilingostrobus longifolius的孢子叶球以及解剖特点的分析,我们认为它代表了晚泥盆世石松类中较为先进的一个类群,这种类群在石炭纪时期得到大规模发展。 结合晚泥盆世其他具有生殖结构的石松类,我们认为晚泥盆世时期石松类的生殖结构类型丰富多样,而且远比中泥盆世石松类生殖结构复杂。这个时期石松类的发展为其在石炭纪的进一步演化奠定了基础。同时,在这个时期石松类植物的叶舌与孢子类型关系中,包括四种类型,即不具叶舌产生单型孢子类型,不具叶舌产生异型孢子类型,具叶舌产生单型孢子类型以及具叶舌产生异型孢子类型。这与现代石松类仅具有两种类型即不具叶舌的类群孢子囊产生同型孢子,而具叶舌的类群孢子囊产生异型孢子有很大的差别。

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The oil and gas potential of Northeast Asia is enormous, but the degree of exploration is very low in Northeast Asia (the degree is below 3%-10%).The reasons are as follows: First, it is relatively difficult to study the oil and gas bearing basins(OGB), which are of multiple types, in different tectonic settings, with complex geologic frameworks and with long-term geologic evolution. Secondly, because of the non-equilibrium in development of economy and regional market, application of theories and techniques and the research levels in different countries, the conclusions are not conformable, and even contradictory. Thirdly, most of the former researches were limited to one territory or one basin, and lack of systematical and in-depth study on geotectonic evolution, classification of basins, and the evaluation of hydrocarbon resources. In this thesis, integrated study of the regional tectonic feature and basin features of Northeast Asia was done, to understand the basin evolution history and the controlling action on oil and gas. Then, new conclusions are and exploration proposals are as following: 1. Geotectonic evolution in Northeast Asia: The main structural motion system in Paleozoic Era was longitudinal, and in Meso-cenozoic was latitudinal with the Pacific Ocean. The whole evolution history was just the one of pulling-apart, cutting-out, underthrusting and collision of the Central Asia- Mongolia Ocean and the Pacific Ocean. 2. The evolution characteristics of basins in Northeast Asia: mainly developed from longitudinal paste-up, collision and relaxation rifting motion in Paleozoic-Early Mesozoic Era and from underthrust, accretion, and receding of subducted zone of the Pacific Ocean in Late Mesozoic Era-Cenozoic Era. 3. The research in basin classification of Northeast Asia: According to geotectonic system, the basins can be classified into three types: intracratonic, pericratonic and active zone basin. And they can be further classified into 18 different types according to genetic mechanism and dynamic features. 4. The master control factors of oil and gas accumulation in Northeast Asia: high quality cap-rock for craton and pericrationic basin, the effective source rock and high quality cap-rock for Mesozoic rifted basins, intra-arc, fore-arc and back-arc basins. Graded exploration potential of oil and gas for basin in Northeast Asia according to 7 factor, hereby, divided the oil and gas potential of basins into 5 levels. 5. Evaluation of hydrocarbon resources: The difference of resource potential among these basins is huge in Northeast Asia. The evaluation of Mesozoic rifted basin and Pacific Ocean basin showed that the large scale rifted basin and retroarc basin(including backarc marginal sea basin) have great resource potential. 6. The writer believes that the next step should pay more attention to the evaluation of petroleum resource in Far East part of Russia and trace them. On the other hand, according to integrated analysis of oil/gas resource potential and the operation difficulty in this area, suggests that East-Siberia basin, East-Gobi-Tamchag basin, Sakhalin basin, North-Okhotck basin, West-Kamchatka basin could be as cooperation priority basins in future.

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The north steep slope zone of Dongying Depression has great potential in oil resource and as the usage of 3-d seismic data in the last decade, the exploration of oil and gas has get into the stage of sandy glavel body lithological oil-gas pool exploration. In this thesis, writer take the north steep slope zone of Dongying Depression as target area and take Sha-III and Sha-[V Menber as purpose stratum, study on sequence stratigraphy, depositional system, reservoir description, emphasesing on analyzing of forming of lithological oil-gas pool, especially the dynamics principle of oil and gas preliminary movement from the source rock to the reservoir form lithological oil-gas pools. The aim of this work is to give some quantitatively explanation for the mechanism of lithological oil-gas pool forming, and set up the theory of pool form with characteristic terrestrial faulted basin. There are main conclusions and views as follow. 1. Applying with principle of sequence stratigrapgy, according to the depositional cycles of Dongying Depression, the sequence stratigraphical partition of Tertiary was finished, stressing on dismembering Sha-III and Sha-IV Menber as 5system tracts. 2. The structure of Dongying Depression especially of the north steep slope zone has accomplished, including the analyzing the structural cortroling to depositional condition of the north steep slope zone of Dongying Depression, discussed relationship between the structure of the north steep slope zone and the pool-forming. 3. The horizontal and vertical exchanges of ancient climates and ancient physiognomy of the all stratum units and studies on characteristic of depositional system distribution have been finished, found that there are five depositional systems in the north steep slope zone of Dongying Depression as fluvial, delta (tan-delta), sub-water fluvial fan lacustrine, gravitive flow, and seven formations of sandy glavel body, and forecasting of all kinds of sandy glavel body has been made. 4. Seismic stratigraphy and log stratigraphy have been made, described and forecasted all kinds of reservoir of objective stratum by means of physical geography method, setup a series means of sandy glavel body description suit to target area. 5. The pool-forming system has been studied, analyzing all the elements in petroleum sub-system of Sha-III and Sha-IV Menber of Dongying Depression with view of source controlling, estimated the petroleum system applying source rock potential index combining with distribution ofreservior. 6.Through studying types of pool, the controlling factors of pool-forming of sandy glavel body were discussed by deposition stages, formation types, structure ect. as a conclusion that the characteristics of pool forming in the north steep slope zone of Dongying Depression are, the controlling factor of the pools is mainly lithology, petrophysics of oil sands vary greatly, with a large heterogeneity, all kind of reservoir with different formation has different pool-forming conditions, and as a result, formed various pools of sandy glavel body along the steep slope with regular combination, distribution and constituted the multiple petroleum accumulative pattern. 7. It's the first time to cauculate and estimate the fluid pressure in source rock of Dongying Depression, set up the stratum fluid pressure in Dongying Depression, and firstly use equivalent charging pressure and reservoir forming index to quantitatively evaluate the pool-forming condition of lithological pool.8. Above all studies, follow up the scent of the exploration combined with practice a lot of explorative targets were found, and got geat economic and social benefit.