首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   78篇
  免费   5篇
  国内免费   27篇
大气科学   10篇
地球物理   7篇
地质学   75篇
海洋学   10篇
天文学   1篇
综合类   5篇
自然地理   2篇
  2014年   1篇
  2013年   2篇
  2011年   1篇
  2010年   5篇
  2009年   6篇
  2008年   11篇
  2007年   7篇
  2006年   9篇
  2005年   8篇
  2004年   13篇
  2003年   7篇
  2002年   2篇
  2001年   11篇
  2000年   5篇
  1999年   2篇
  1998年   6篇
  1997年   1篇
  1996年   1篇
  1994年   2篇
  1993年   1篇
  1991年   3篇
  1990年   1篇
  1989年   2篇
  1988年   1篇
  1960年   1篇
  1959年   1篇
排序方式: 共有110条查询结果,搜索用时 265 毫秒
11.
Mineral-bituminous matrix(MBM) makes up a major part of source rocks,but its potential in hydrocarbon generation is uncertain,Mineral and organic (Maceral and kerogen) compositions,organic maturity and fluorescence of MBM are studied based on source rock samples from eastern Jiuquan(Jiudong)Basin.The results show that MBM is dominated by inorganic minerals and among the small percentage of organic components those of secondary origins are predominant over the primary species.This strongly indicates that the significance of MBM in hydrocarbon generation is limited.  相似文献   
12.
石油开采业,石油加工业和石油运输业的生产与运行对周围环境都有强烈的影响。除了石油产品之外,许多其它含碳物质都是污染要素。目前采用的污染评价方法都要求用有机溶剂从样品中萃取污染物。由于不同能完全萃取,所以对污染的测定未必准确。通过土壤反射性能评价石油污染的方法,仅能近似地测定污染值。我们认为,通过样品在氧气或者空气流中燃烧时释放的碳酸气数量计算有机碳含量,测定石油产品和其它含碳物质污染土壤的方法是地  相似文献   
13.
A field work has been carried out to identify the occurrence of oil and oil products pollution in mangrove sediment from Red Sea of Yemen. The concentration of total petroleum hydrocarbons is from 700 ng/g at Kamaran Island station to 400 ng/g at Al-Hodiedah station, and the total organic carbon ( TOC) in samples ranges from 0.07% at Dhubab station to 0.03% at Kamaran Island station. This pollution is as a result of localized oil pollution and /or heavy ship traffic in the Red Sea and Gulf of Aden.  相似文献   
14.
MONITORING POLYNUCLEAR AROMATIC HYDROCARBONS IN SEDIMENT POREWATER BY SPMD   总被引:1,自引:0,他引:1  
A new mimic biological Semi-permeable Membrane Device (SPMD) introduced for sampling organic pollutants yielded satisfactory results when it was frrst used as a passive sampler to concentrate and determine 16 kinds of polynuclear aromatic hydrocarbons (PAHs) by means of capillary GC on an HP 5890 GC-FID in coastal sediment perewater. The concentration of PAHs in sediment porewater for naphthalene(N), acenaphthlene(AL), acenaphthene (AE), fluorene (F), phenaphthene(P), anthracene(A), fluoranthene(FA), pyrene(Py), benzo[a]anthracene(B[a]A), chrysene(Chr), benzo[b] fluor- anthene(B[b]F), benzo[k]fluoranthene(B[k]F), benzo[a]pyrene(B[a]P),indeno[1,2,3,-cd]-Pyrene(I[123]P), dibenz[a,h]anthracene(D[ab]A) and benzo[g,h,i] perylene(B[ghi]P) were:50.36, under detection limits(UD), 18.19, 8.41, 8.40, 1.44, UD, 8.01, 524.15, 168.47, 50.13,123.66, 63.48, 27.40, 82.04 and 58,81 ng/L, respectively.  相似文献   
15.
A field work has been carried out to identify the occurrence of oil and oil products pollution in mangrove sediment from Red Sea of Yemen. The concentration of total petroleum hydrocarbons is from 700ng/g at Kamaran Island station to 400 ng/g at Al-Hodiedah station, and the total organic carbon (TOC) in samples ranges from 0. 07% at Dhubab station to 0. 03% at Kamaran Island station. This pollution is as a result of localized oil pollution and/or heavy ship traffic in the Red Sea and Gulf of Aden.  相似文献   
16.
广东灰霾天气预警指标及时空分布   总被引:4,自引:2,他引:2  
陈慧华  王春林  黄珍珠 《广东气象》2008,30(5):F0002-F0002
霾,也称灰霾,香港澳门一带称之为烟霞,是指悬浮在大气中的大量微小尘粒、烟粒、硫酸与硫酸盐、硝酸与硝酸盐、有机碳氢化合物等化学物质微粒的非水成物组成,导致大气浑浊、视野模糊、水平能见度〈10km的气溶胶系统。目前我国有4个灰霾严重地区:黄淮海地区、长江河谷、四川盆地和珠江三角洲。  相似文献   
17.
In order to investigate the mechanism of formation of abiogenetic hydrocarbons at the depth of the Earth,experimental research on reactions between carbonates and water or waterbearing minerals was carried out at the pressure of about 1GPa and the temperature range of 800-1500℃.The reactions took place in an open and nonequilibrium state.Chromatographic analyses of the gas products indicate that in the experiments there were generated CH4-dominated hydrocarbons,along with some CO2 and CO.Accordingly,we think there is no essential distinction between free-state water and hydroxy in the minerals in the process of hydrocarbon formation.This study indicates that reactions between carbonates and water or water-bearing minerals should be an important factor leading to the formation of abiogenetic hydrocarbons at the Earth‘s depth.  相似文献   
18.
化石燃料     
《地球》2014,(4):105-105
化石燃料亦称矿石燃料.是一种碳氢化合物或其衍生物.其包括的天然资源为煤炭、石油和天然气等。化石燃料的运用能使工业大规模发展.而替代水车。当发电的时候.在燃烧化石燃料的过程中会产生能量.从而推动涡轮机产生动力。旧式的发电机是使用蒸汽来推动涡轮机的。现时.很多发电站都已采用燃气涡轮引擎。那是利用燃气直接来推动涡轮机的。  相似文献   
19.
Samples of suspended particulate matters(SPMs),surface sediment and road dust were collected from the Yangtze estuarine and nearby coastal areas,coastal rivers,and central Shanghai.The samples were analyzed for the presence of 16 polycyclic aromatic hydrocarbons(PAHs)in the USEPA priority-controlled list by GC-MS.The compound-specific stable carbon isotopes of the individual PAHs were also analyzed by GC-C-IRMS.The sources of PAHs in the SPMs and surface sediments in the Yangtze estuarine and nearby coastal...  相似文献   
20.
李宏博  于怀 《地球》2010,(1):38-39
化石能源是指经地质作用形成的、可用作燃料的碳氢化合物的通称.包括石油、煤炭、天然气、煤层气和可燃冰等。化石能源对人类生活的重要性不言而喻。吃穿住行都离不开它的身影。自工业革命以来的二百多年,人类社会高度现代化和文明的实现是以化石能源为主要推动力的。  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号