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排序方式: 共有89条查询结果,搜索用时 46 毫秒
1.
In this paper, residual and regional gravity and magnetic anomalies of Saros Bay are separated using wavelet method. Wavelet is one of the modern, stochastic image approaches processing technique in electronics. The vertical, horizontal and diagonal components of wavelet output are evaluated simultaneously and an underground model is obtained by suitable cross-sections. Thus the geological and tectonic properties of Saros Bay are extracted. Our proposed model is confirmed by deep and shallow seismic researches of Turkish Petroleum Cooperation (TPAO). The South-East region of Saros Graben is formed by strike slip Ganos Fault and Anafartalar reverse Fault that lies on the east of Ganos Fault. On the Northwest region, there is strike slip component fault resulting in the Enez Graben. Here we detected two new oval type geological structure, both of them starting from the Eastern direction of Canakkale Dardanelles and but one of them continuing through Gelibolu Peninsuls, while the other tending to the Enez Graben. We think that these structures are the ruins of a very old sea in this region. This revised version was published online in November 2006 with corrections to the Cover Date.  相似文献   
2.
In a simplified model of the Earth-Moon-Sun system based on the restricted circular 3-dimensional 3-body problem, it is possible to find numerically a set of 8 periodic orbits whose time evolutions closely resemble that of the Moon's orbit. These orbits have a period of 223 synodic months (i.e. the period of the Saros cycle known for more than two millennia as a means of predicting eclipses), and are characterized by a secular rotation of the argument of perigee . Periodic orbits of longer durations exhibiting this last feature are very abundant in Earth-Moon-Sun dynamical models. Their arrangement in the space of the mean orbital elements- for various values of the lunar mean motion is presented.  相似文献   
3.
半乳糖凝集素-8基因(galectin-8,Gal-8)属于凝集素家族一员。已知Gal-8在哺乳动物的先天免疫中发挥重要作用,然而在鱼类中却鲜有报道。本研究通过转录组测序获得大弹涂鱼(Boleophthalmus pectinirostris)半乳糖凝集素-8样基因(galectin-8 like,Bp Gal-8L)c DNA序列。首先确定其序列特征,其次采用实时定量PCR(real-time quantitative PCR,q PCR)的方法鉴定Bp Gal-8L组织表达分布及其与迟缓爱德华氏菌(Edwardsiella tarda)感染相关性;最后分别通过原核表达获得N端和C端CRD区重组蛋白Bp Gal-8L-N和Bp Gal-8L-C,并采用玻片法观察这两个CRD区的细菌凝集活性和糖类结合特性。多重序列比对显示,Bp Gal-8L蛋白含有两个糖识别结构域(carbohydrate recognition domain,CRD),但只有C端的CRD区存在Gal家族典型的β-半乳糖苷糖类结合基序。系统进化树表明Bp Gal-8L属于鱼类Gal-8的一种亚型。q PCR结果显示,Bp Gal-8L基因m RNA在各组织中普遍表达,并且在迟缓爱德华氏菌感染后大弹涂鱼肝和脾中表达量呈上调趋势。细菌凝集实验结果显示,只有Bp Gal-8L-C重组蛋白对检测的5种革兰氏阴性菌及2种革兰氏阳性菌有凝集作用,并与乳糖和脂多糖特异性结合。综上所述,Bp Gal-8L与大弹涂鱼抗菌免疫密切相关,且其N端和C端CRD区发挥不同作用。  相似文献   
4.
本文讨论了准噶尔盆地北部地区姜石层的特征及成因,北准地区新第三系至第四系出现多层姜石层,这些姜石层的存在,表明该地区具有形成第三系可地浸砂岩型铀矿的良好前景。  相似文献   
5.
Tectonic elements controlling the evolution of the Gulf of Saros have been studied based upon the high-resolution shallow seismic data integrated with the geological field observations. Evolution of the Gulf of Saros started in the Middle to Late Miocene due to the NW–SE compression caused by the counterclockwise movement of the Thrace and Biga peninsulas along the Thrace Fault Zone. Hence, the North Anatolian Fault Zone is not an active structural element responsible for the starting of the evolution of the Gulf of Saros. The compression caused by the rotational movement was compensated by tectonic escape along the pre-existing Ganos Fault System. Two most significant controllers of this deformation are the sinistral Ganos Fault and the dextral northern Saros Fault Zone both extending along the Gulf of Saros. The most important evidences of this movement are the left- and right-oriented shear deformations, which are correlated with structural elements, observed on the land and on the high-resolution shallow seismic records at the sea. Another important line of evidence supporting the evolution of this deformation is that the transgression started in the early-Late Miocene and turned, as a result of regional uplift, into a regression on the Gelibolu Peninsula during the Turolian and in the north of the Saros Trough during the Early Pliocene. The deformation on the Gelibolu Peninsula continued effectively until the Pleistocene. Taking into account the fact that this deformation affected the Late Pleistocene units of the Marmara Formation, the graben formation of the Gulf of Saros is interpreted as a Recent event. However, at least a small amount of compression on the Gelibolu Peninsula is observed. It is also evident that compression ceased at the northern shelf area of the Gulf of Saros.  相似文献   
6.
区域似大地水准面精化研究主要是用于测绘学科,将精化结果应用到绘制地形图中,减少户外工作量,降低人力成本。传统采用的Kriging法在精化时会出现误差,精度值不达标。所以,改用了一种基于已知的拟合残差进行计算的改进方法重新精化研究。将改进的Kriging法与传统的Kriging法对比后,改进后的方法精化结果的拟合精度明显要高于传统方法。  相似文献   
7.
胡庆成  闫浩  吴春明 《地质论评》2014,60(3):601-610
斑岩—浅成低温热液型Cu—Au成矿流体最具代表性的是H2O—Cl—S流体。流体的性质强烈控制着Cu、Au的成矿行为,包括溶解性、迁移形式和气—液分配。流体的氧逸度和流体中Cl、S物种相对含量决定金属在流体中的溶解形式,高氧逸度的高温高盐度流体中Cu、Au主要和Cl络合,S-3也可能是促进Au溶解的重要S物种形式。而过量的S有利于Cu、Au等元素以含S离子络合物进入液相流体,与含S中性络合物配分进入气相流体并迁移Au至浅成低温热液环境形成矿床。岩浆需要经历充分的分异,出溶成分和性质有利于金属迁移的流体,形成高品位的斑岩型Cu、Au矿体;上覆叠加浅成低温热液型Au矿体可能需要初始的成矿流体状态进入NaCl—H2O的超临界区、有效的演化方式、良好的流体缓冲环境和有利的Au沉淀场所。相分离和流体—流体反应是沉淀斑岩—浅成低温热液型Cu—Au矿体最重要的流体演化方式。气相流体具有独特的流体性质和演化方式,可能成为十分重要的成矿流体。  相似文献   
8.
H. Kiliç 《Solar physics》2009,255(1):155-162
The short-term periodicities in sunspot numbers, sunspot areas, and flare index data are investigated in detail using the Date Compensated Discrete Fourier Transform (DCDFT) for the full disk of the Sun separately over the rising, the maximum, and the declining portions of solar cycle 23 (1996 – 2006). While sunspot numbers and areas show several significant periodicities in a wide range between 23.1 and 36.4 days, the flare index data do not exhibit any significant periodicity. The earlier conclusion of Pap, Tobiska, and Bouwer (1990, Solar Phys. 129, 165) and Kane (2003, J. Atmos. Solar-Terr. Phys. 65, 1169), that the 27-day periodicity is more pronounced in the declining portion of a solar cycle than in the rising and maximum ones, seems to be true for sunspot numbers and sunspot area data analyzed here during solar cycle 23.  相似文献   
9.
文章论述了珠江三角洲河网的发育、演变过程和整治方案。由于人类活动影响,珠江三角洲河网区西、北两江下游放射状河系支汊淤断及消亡,使西、北两江正干均成为单一水道;在两江汇流区内又受绥江三角洲南展而分离开来,只留一条狭窄的小河涌(思贤)连接;由于北江正干的淤积、西江正干刷深,使古代(唐代以前)西江合北江同流向东流入番禺(广州)的形势大变,形成江水反向西流入西江,西江水不能过入广州。由此,西、北两江合成的珠江三角洲主体网河区成为浅水狭窄的小河区,以往主要干流多不复存在,生态环境日益变劣。因此,需要修复河网。关键是把西江大量优质水源(沙少、污染少)引回,过入珠江三角洲网河区,北江水源也需截流使其不再西流入西江;开通北江大堤沿途防西水的闸门(如芦苞、西南、沙口等闸),以便通水通航;在思贤建立新型分水闸,可将西、北两江正干水源恢复到良好生态环境  相似文献   
10.
本文从水产无脊椎动物与环境的关系论述其来克丁物质的功能;来克丁与微生物间的相互作用包括相互作用中有关来克丁、微生物种类,作用部位和作用物质等。从来克丁在水产无脊椎动物识别外来物质,包括抵御病原体的作用看,健康发展的水产业之一项关键任务便是认识和掌握来克丁在御防病害活动中的机理。  相似文献   
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