全文获取类型
收费全文 | 172篇 |
免费 | 8篇 |
国内免费 | 10篇 |
专业分类
综合类 | 16篇 |
化学工业 | 36篇 |
机械仪表 | 3篇 |
建筑科学 | 2篇 |
矿业工程 | 35篇 |
能源动力 | 8篇 |
石油天然气 | 81篇 |
无线电 | 1篇 |
冶金工业 | 6篇 |
自动化技术 | 2篇 |
出版年
2025年 | 2篇 |
2024年 | 4篇 |
2023年 | 4篇 |
2022年 | 4篇 |
2021年 | 11篇 |
2020年 | 6篇 |
2019年 | 5篇 |
2018年 | 7篇 |
2017年 | 4篇 |
2016年 | 5篇 |
2015年 | 8篇 |
2014年 | 3篇 |
2013年 | 10篇 |
2012年 | 10篇 |
2011年 | 4篇 |
2010年 | 7篇 |
2009年 | 13篇 |
2008年 | 5篇 |
2007年 | 6篇 |
2006年 | 4篇 |
2005年 | 8篇 |
2004年 | 2篇 |
2003年 | 4篇 |
2002年 | 11篇 |
2001年 | 5篇 |
2000年 | 7篇 |
1999年 | 4篇 |
1998年 | 6篇 |
1997年 | 1篇 |
1996年 | 3篇 |
1995年 | 5篇 |
1994年 | 3篇 |
1993年 | 2篇 |
1992年 | 1篇 |
1991年 | 3篇 |
1985年 | 2篇 |
1984年 | 1篇 |
排序方式: 共有190条查询结果,搜索用时 15 毫秒
1.
英国煤显微组分的分离及常压CO2气化动力学研究 总被引:3,自引:0,他引:3
对英国煤进行了显微组分的分离富集,得到了镜质组、丝质组和稳定组三种富集物。使用多气氛高温高压热重装置,对镜质组富集物煤焦进行了CO_2气化动力学研究。所用压力为1atm,温度范围980~1070℃之间。结果表明,镜质组富集物焦样气化动力学符合1-(1-x) ̄(1/3)=kt,气化模型可用收缩核模型描述。对三种富集物进行非等温热重实验中,由热重曲线求得动力学参数。作者认为,在选择合适的动力学模型的基础上,由程序升温热重曲线求动力学参数是简便可靠的。 相似文献
2.
大同煤田七峰山矿2号煤层若干微量元素地球化学特征 总被引:2,自引:0,他引:2
为查明大同煤田七峰山2号煤中微量元素的地球化学特征,应用电感耦合等离子体质谱(ICP-MS)方法测定煤中15种微量元素的含量;采用光学显微镜和X射线衍射(XRD)方法观测煤中矿物组成特征,运用数理统计方法分析煤中微量元素的有机亲和性、赋存特征等问题。研究表明:形成于陆相环境的七峰山2号煤,微量元素含量相对较低,其质量分数普遍低于相应元素在华北或中国煤中的质量分数,只有As,Re,Mo,Se的富集系数高于6,属富集元素。2号煤中Mo为强亲有机元素,Be,W,Tl,Co为亲有机元素,As,Th,Se,Sb,Ni,Li和Bi为无机-有机元素,Pb,Re,Sc不具有机亲和性。元素在煤中的赋存状态主要以铝硅酸盐结合态、有机结合态、碳酸盐和无机化合物形式为主。 相似文献
3.
Bituminous coals produced in the Ostrava—Karviná coal basin show considerable variation in their maceral composition and rank. In order to explain the significance of the petrographic composition, structure and chemical parameters in coal degradation processes, a large number of coal samples was investigated. From the relationships obtained, the behaviour of macerals during these processes is discussed. It is found that isometamorphic vitrinites are characterized by a distinctive behaviour affected to a first approximation by the atomic ratios C/H and C/O. Inertinite, despite its occasional significantly higher volatile matter, does not yield an appreciable amount of fused material. 相似文献
4.
Concentrates of vitrinite and inertinite macerals have been pyrolysed in a flame under conditions representative of the initial stages of pulverized coal combustion. Char was distinguished from soot by size analysis and the char yield correlated with the proximate analysis. The char morphology was studied by optical microscopy and quantitative measurements of porosity and pore size were made using image analysis. Vitrinite and inertinite produce chars of characteristic morphology. The softening behaviour of inertinite varies with coal rank and can be related to the optical reflectance. The porosity of vitrinite chars approaches that of inertinite chars at high rank. 相似文献
5.
Guoliang XIE;Shugen LIU;Kun JIAO;Bin DENG;Yuehao YE;Wei SUN;Zeqi LI;Wenping LIU;Chao LUO;Zhangchang LI 《天然气工业》2021,41(09)
At present,the identification of organic matter components in deep shale and the quantitative characterization of their pores are not researched sufficiently,which makes it difficult to evaluate the exploration and development potential of deep shale gas in the Sichuan Basin. Taking the deep shale of Upper Ordovician Wufeng Formation-Lower Silurian Longmaxi Formation in the Sichuan Basin as an example,this paper effectively identifies the organic matter components in deep shale by means of optical microscope,scanning electron microscope (SEM) and energy dispersion spectrometry(EDS) analysis. In addition,the pore growth characteristics of different organic matter components are quantitatively compared by using the PCAS software,and the growth of organic pores,the preservation mechanism of pyrobitumen pores and their geological significance are discussed. And the following research results are obtained. First,the organic matter components in deep shale are mainly bitumen and kerogen,and bitumen is dominated by pyrobitumen. Shape and non-fixed shape pyrobitumen can be identified. Algal fragment,bacteria-like aggregate,graptolite and micrinite can be identified in kerogen. Second,the growth characteristics of organic pores are closely related to the type of organic matter components. The pores in pyrobitu-men are quite developed and they are mostly bubble and spongy shaped pores. There are a few or no pores in algal fragments. Irregular pores are developed in bacteria-like aggregates. And,visual pores are basically undeveloped in graptolite and micrinite. Third,the pyro-bitumen pores in siliceous shale are more developed than those in clay shale,and quartz is superior to pyrite and carbonates minerals in pore protection. Fourth,the pores in non-fixed shape pyrobitumen,bacteria-like aggregates and algal fragments are mainly mesopores,whereas spherical pyrobitumen is dominated by large mesopores and macropores. The growth of the pores in algal fragments is related to their original types. In conclusion,the parameters (e.g. diameter and form factor) of pyrobitumen pores in deep shale can reflect the pres-sure environment of strata to some extent and further reflect the enrichment situations of shale gas indirectly. 相似文献
6.
图像法测定煤岩组分反射率工作曲线的建立与应用 总被引:1,自引:0,他引:1
基于图像分析的煤岩自动测试系统测定煤岩组分反射率的理论依据是物质的反射率值与图像的灰度值呈正比关系,工作曲线的建立是测定显微组分反射率的前提。系统分析了图像法测定反射率的原理、测试流程、原理公式,并利用煤岩自动测试系统进行建立工作曲线的试验研究和验证,分析工作曲线的最大量程和反射率的分辨能力,提出在实际测试中工作曲线的选择原则。工作曲线的斜率、最大量程、分辨能力均可通过改变显微镜照明强度和显微数码照相机曝光时间两种方式调整。256级灰度值的显微数码照相机满足图像法测定反射率的精度要求。反射率自动测试系统与传统的光度计法的测试结果的平均值和直方图对比性强。 相似文献
7.
中生代-新生代大陆边缘盆地海相烃源岩成因类型 总被引:4,自引:2,他引:4
中生代-新生代大陆边缘盆地海相烃源岩虽沉积于海洋环境,但有机质生源输入复杂。海相烃源岩显微组分组成中不仅有代表低等水生生物输入的腐泥组分,而且有较多指示陆生高等植物成因的镜质组、惰质组或壳质组。烃源岩生物标志化合物的分布特征也呈现出有机质生源输入二元性的特点,具体表现在饱和烃正构烷烃的分布面貌以双峰态为主,部分呈单峰态。C27-C29规则甾烷的分布型式以不对称的\"V\"字型为主,部分呈\"L\"型或反\"L\"型分布;除指示水生生物输入的C23三环萜烷外,代表陆源有机质输入的奥利烷、四环萜烷和其他低分子量的三环萜烷均有分布。中生代-新生代大陆边缘盆地海相烃源岩生源组成复杂,这一特殊现象是大陆边缘盆地海洋和大陆两种地质营力、低等水生生物和陆生高等植物双重生源输入共同作用的结果。根据生源构成可将中生代-新生代大陆边缘盆地海相烃源岩划分为3种成因类型,即以藻类生源输入为主的内源型、以高等植物输入为主的陆源型及介于两者之间的混合生源型,并进一步揭示海相烃源岩的成因类型与干酪根类型之间可以通过显微组分组成、有机元素组成以及生物标志化合物分布联系起来。 相似文献
8.
9.
运用有机岩石学全岩分析方法,对新疆三塘湖盆地中、下侏罗统煤系烃源岩进行了显微组分组成与生烃组分剖析。三塘湖盆地烃源岩显微组分中富含镜质组、贫腐泥组,明显具有高等植物陆源有机质占绝对优势的特点。显微组分含量与组成在各层段中呈现均不衡性,八道湾组为该区的主力烃源岩,孢子体和角质体是煤成油的最主要的生烃组分,渗出沥青体、微粒体的出现为该区烃类生成提供了证据。 相似文献
10.
《Egyptian Journal of Petroleum》2020,29(3):243-249
The hydrocarbon potential is determined by the quantity and quality of organic matter encountered in the Jurassic sediments in two wells at the Northern Western Desert. It utilizes to define the zones of oil and gas using the well logging data for calculates the total organic carbon (TOC). The evaluation of source rock has been based on two steps; the first one depended on the geochemical parameters including TOC, S1, S2, Tmax, and Vitrinite reflectance (Ro %) of two wells JG-1 and JD-4. The second step was to calculate (TOC) from wireline logs. The well log types utilized in such kind of analysis are the density log, sonic log, resistivity log and gamma-ray log. The stratigraphic sequence, in the studied wells ranges in age from Paleozoic to Recent. The present work focuses on the Jurassic rocks represented by Khatatba Formation as they include the main source horizon. Based on the obtained results, Jurassic sediments called as fair to excellent source rock potential. The genetic type of organic matter can be identified through the study of pyrolysis data, which indicate that is rich in mixed oil and gas-prone kerogen except few samples reflect type I organic facies. 相似文献