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41.
亚热带森林非甲烷碳氢化合物的研究 I.季节变化(钢瓶采样) 总被引:1,自引:2,他引:1
对中国亚热带森林地区的非甲烷碳氢化合物(NMHC)进行了一年多的钢瓶采样,并利用气相色谱仪对空气样品进行了分析,得到了大量NMHC的实测资料以及它们的季节变化规律和相互之间的关系.研究表明,NMHC的主要来源是当地植物的排放.对异戊二烯及其影响因子进行了详细研究. 相似文献
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The Jiyang Sag and the Liaohe Basin are the two important areas where immature oil resources are distributed in China. From these two areas immature-low mature to mature oil samples were collected for carbon isotopic analysis. The extracts of source rocks are dominant in the Jiyang Sag while crude oils are dominant in the Liaohe Basin. The maturity index, Ro, for source rocks varies from 0.25%(immature) to 0.65% (mature). Studies have shown that within this range of Ro values the extracts of source rocks and crude oils, as well as their fraction components, have experienced observable carbon isotope fractionation. The carbon isotopic values tend to increase with burial depth, the oils become from immature-low mature to mature, and the rules of evolution of oils show a three-stage evolution pattern, i. e. ,light→heavy→light→heavy oils. Such variation trend seems to be related to the occurrence of two hydrocarbon-generating processes and the main hydrocarbon-forming materials being correspondingly non-hydrocarbons and possessing MAB characteristics, lower thermodynamic effects and other factors. In the process towards the mature stage, with increasing thermodynamic effects, the thermal degradation of kerogens into oil has become the leading factor, and correspondingly the bond-breaking ratio of ^12C-^13C also increases,making the relatively ^12C-rich materials at the low mature stage evolve again towards ^13C enrichment. 相似文献
43.
深源花岗岩中的碳氢化合物 总被引:2,自引:0,他引:2
利用石油地球化学的溶剂抽提和气相色谱技术研究了北京延庆碓臼峪花岗岩(深源花岗岩)样品中的可溶有机质,同时用高温处理过的石英砂进行空白对比实验。结果表明,所研究的两个花岗岩样品中均存在少量的高碳数碳氢化合物,且具有相同的成分特征。这为自然界存在深源的长链碳氢化合物提供了新的证据,也为解释花岗岩浆演化晚期水热流体中短链羧酸的成因提供了线索。 相似文献
44.
In order to investigate the migration and accumulation efficiency of hydrocarbon natural gas in the Xujiaweizi fault depression, and to provide new evidence for the classification of its genesis, a source rock pyrolysis experiment in a closed system was designed and carried out. Based on this, kinetic models for describing gas generation from organic matter and carbon isotope fractionation during this process were established, calibrated and then extrapolated to geologic conditions by combining the thermal history data of the Xushen-1 Well. The results indicate that the coal measures in the Xujiaweizi fault depression are typical "high-efficiency gas sources", the natural gas generated from them has a high migration and accumulation efficiency, and consequently a large-scale natural gas accumulation occurred in the area. The highly/over matured coal measures in the Xujiaweizi fault depression generate coaliferous gas with a high δ^13C1 value (〉 -20‰) at the late stage, making the carbon isotope composition of organic alkane gases abnormally heavy. In addition, the mixing and dissipation through the caprock of natural gas can result in the negative carbon isotope sequence (δ^13C1 〉δ^13C2 〉δ^13C3 〉δ^13C4) of organic alkane gases, and the dissipation can also lead to the abnormally heavy carbon isotope composition of organic alkane gases. As for the discovery of inorganic nonhydrocarbon gas reservoirs, it can only serve as an accessorial evidence rather than a direct evidence that the hydrocarbon gas is inorganic. As a result, it needs stronger evidence to classify the hydrocarbon natural gas in the Xujiaweizi fault depression as inorganic gas. 相似文献
45.
碳氢化合物的底部界线LanR.MacDonald海洋气体水合物为水和甲烷的混合物,可能是烃类资源的主矿脉,其有机碳储量比全球石油埋藏量大得多。并且能够与大气层相互作用影响气候循环。在布莱克海脊,钻进海底模拟反射层(BSR)支持关于一个气体水合物地层能... 相似文献
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The origin and distribution of natural gas in the frontal uplift area of the Kuqa depression,Tarim Basin 总被引:1,自引:0,他引:1
The frontal uplift of the Kuqa depression is an important oil and gas producing area. In this study, the distribution and origin of natural gas were discussed based on natural gas components and isotope data. The main components of natural gas were hydrocarbons with relatively high contents of C2+ component. Most gases were de-rived from terrestrial source rocks, and some came from marine rocks. The contents of non-hydrocarbon gases were high in the central part of the frontal uplift area and low in the two terminals. The distribution of oil composition was similar to that of natural gas, which was mainly controlled by the types of source rocks. Dry coefficient and maturity of natural gas in the frontal uplift were lower than those of gas in the Kelasu tectonic belt of the Kuqa depression, which was mainly affected by the difference of tectonic movements in both areas. In the frontal uplift, the traps were formed in the early stage and could capture the early formed oil and gas, and structural adjustment was slight in later stages, so the oil and gas could be effectively preserved. Multiperiodic oil and gas filling led to the complex distribu-tion of natural gas. 相似文献
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