全文获取类型
收费全文 | 186篇 |
免费 | 8篇 |
专业分类
综合类 | 2篇 |
化学工业 | 9篇 |
机械仪表 | 4篇 |
建筑科学 | 42篇 |
矿业工程 | 1篇 |
能源动力 | 19篇 |
轻工业 | 12篇 |
水利工程 | 14篇 |
石油天然气 | 51篇 |
无线电 | 2篇 |
一般工业技术 | 16篇 |
冶金工业 | 13篇 |
原子能技术 | 2篇 |
自动化技术 | 7篇 |
出版年
2024年 | 1篇 |
2023年 | 1篇 |
2022年 | 2篇 |
2021年 | 1篇 |
2020年 | 6篇 |
2019年 | 9篇 |
2018年 | 19篇 |
2017年 | 5篇 |
2016年 | 23篇 |
2015年 | 4篇 |
2014年 | 7篇 |
2013年 | 37篇 |
2012年 | 5篇 |
2011年 | 6篇 |
2010年 | 7篇 |
2009年 | 6篇 |
2008年 | 8篇 |
2007年 | 7篇 |
2006年 | 7篇 |
2005年 | 3篇 |
2004年 | 6篇 |
2003年 | 2篇 |
2002年 | 6篇 |
2001年 | 1篇 |
2000年 | 2篇 |
1998年 | 1篇 |
1997年 | 2篇 |
1996年 | 3篇 |
1995年 | 2篇 |
1987年 | 1篇 |
1985年 | 3篇 |
1983年 | 1篇 |
排序方式: 共有194条查询结果,搜索用时 406 毫秒
21.
Aly Farag El Sheikha Ana Condur Isabelle Métayer Doan Duy Le Nguyen Gérard Loiseau Didier Montet 《Yeast (Chichester, England)》2009,26(10):567-573
The determination of geographical origin is a demand of the traceability system of import–export food products. One hypothesis for tracing the source of a product is by global analysis of the microbial communities of the food and statistical linkage of this analysis to the geographical origin of the food. For this purpose, a molecular technique employing 26S rDNA profiles generated by PCR–DGGE was used to detect the variation in yeast community structures of three species of Physalis fruit (Physalis ixocarpa Brat, Physalis pubescens L, Physalis pruinosa L) from four Egyptian regions (Qalyoubia, Minufiya, Beheira and Alexandria Governments). When the 26S rDNA profiles were analysed by multivariate analysis, distinct microbial communities were detected. The band profiles of Physalis yeasts from different Governments were specific for each location and could be used as a bar code to discriminate the origin of the fruits. This method is a new traceability tool which provides fruit products with a unique biological bar code and makes it possible to trace back the fruits to their original location. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
22.
Mostafa A. Teama Mohamed A. Kassab Burns A. Cheadle Maher A. Mesbah Ibtehal F. Mohamed Ezz S. El-Din 《Egyptian Journal of Petroleum》2018,27(4)
Ten wells (EW-4, EW-5, EW-6, EW-7, EW-8, EW-9, EW-10, EW-12, EW-13 and EW-15) were interpreted using the composite well logs, data of core analysis, gamma-ray logs, formation micro-imager logs (FMI), and 3D seismic data in SEGY format to understand the stratigraphy of the onshore, Nile Delta, Egypt.The amplitude analysis of 3-D seismic horizon slice of Lower Abu Madi rock unit together with the lithostratigraphic correlation through the study area depending on the gamma-ray log “HSGR” (left to right increasing), and the identification of type of bed geometry, nature of bed contacts, type of the sedimentary structures and the dominant formative paleocurrents by using some available borehole micro-resistivity images (FMI) and core photos. All of these techniques are used together to define the different depositional facies and depositional environment of the Messinian clastics (Lower Abu Madi rock unit), which is considered to be the main reservoir in the El-Wastani gas field, onshore Nile Delta, Egypt.The present study of depositional pattern of the Upper Miocene clastics reservoir (Lower Abu Madi rock unit) revealed that it is represented by high sinuous meandering channels or paleo-valley and three types of fluvial facies were defined; channel fill, channel margin, and floodplain basin. 相似文献
23.
《International Journal of Hydrogen Energy》2022,47(43):18629-18647
The quest for a low-carbon energy transition has grown in recent years as concerns about the effects of climate change have grown. In this context, several governments around the world are concerned about hydrogen's possible role in a decarbonized energy system. As a result, this paper will provide a high-level overview of the hydrogen value chain, as well as an analysis of current and emerging trends in the global hydrogen market, particularly in the Middle East and North Africa (MENA), which are considered the cornerstone of the current global energy system traditional fossil fuel. Egypt, as a case study, could instruct other emerging countries in general, and natural gas suppliers in particular, how to maximize gains by switching from current imports to blue hydrogen made from natural gas. Policymakers who are responsible for Egypt's national hydrogen strategy should focus on global energy insights, international experience, and natural gas-sourced blue hydrogen as a step to renewables-sourced green hydrogen. 相似文献
24.
Mohamed M. El Nady 《Energy Sources, Part A: Recovery, Utilization, and Environmental Effects》2016,38(11):1635-1642
The source rock potentiality of Middle Jurassic–Lower Cretaceous source rocks in Meleiha area was investigated through total organic carbon (TOC), Ro%, and pyrolysis analysis for 38 cutting samples collected from six wells. Also, the geochemical burial history profile to estimate the timing of hydrocarbon generation and expulsion of source rocks was constructed. The result revealed that the main hydrocarbon of source rocks, for the Middle Jurassic (Khatatba Fm.), is mainly mature, and has good capability for producing oil till present time. Lower Cretaceous source rocks (Alam El Bueib Fm.) are mature, derived from mixed organic sources, and have fair to good capability to generate gas and oil. Kharita Formations immature source rocks originating from terrestrial origin and have poor to fair potential to produce gas. 相似文献
25.
Jónatan Ortiz-García 《Textile》2017,15(1):34-47
Pictorial art during the Roman period is a field that has been amply studied, and is generally divided according to the material employed. This article shows that paintings on linen are a form of artistic expression that is well documented in antiquity, and that they represent a primary source for the study of the work done by painters who specialized in funerary art.
The best preserved and largest surviving ancient collection of paintings on cloth comes from Egypt. It is a practice that is closely tied to funerary customs, as is documented from prehistoric times, and that reached its maximum extension during the Roman period. 相似文献
26.
27.
Ali A. El Bassoussi Seham M. El-sabagh Fatma M. Harb 《Petroleum Science and Technology》2018,36(5):384-391
Characterization and correlation of crude oils from some wells in the North Western Desert, based on six crude oil samples, were studied by different analytical techniques, including API gravity, sulfur content, nickel and vanadium, bulk compositions and saturated fraction obtained from gas chromatography have been studied. The results show that the crude oils are normal to medium aromatic oils, with high API gravity and high sulfur content. V, Ni, V/Ni and V/(V + Ni) reflecting oils might be sourced from non-clastic source rocks, possibly carbonates, deposited under anoxic-suboxic conditions. Bulk compositions revealing that the crude oils were derived from marine organic sources. While, the paraffins and naphthenes percent indicates that the oils belong to paraffinic to naphthenic oil types, deposited in slightly anoxic to suboxic conditions and contained marine organic matter. Thermal maturity data showed that the oil samples were generated from mature source rocks. This indicates the studied oil samples are well correlated with each other, where they are similar in their oil type maturation and source depositional environments. 相似文献
28.
Three geologic sections along the main coal seam (MCS) of the Middle Jurassic (Bathonian) Safa Formation of Maghara mine are examined. Samples collected have been studied. The fuel analyses of coal samples were conducted to determine their Rank characteristic. Fuel analysis classified the studied Maghara MCS as high grade coal, medium rank (D) of para-bituminous class based on its average values of ash content 7.1% (dry-base; d.b), gross calorific value (29 Mj/kg; moist ash free) and random vitrinite reflectance 0.43%. Synonym nomenclature of the studied Maghara coal based to ASTM classification is high volatile (C) class of bituminous group with agglomerating character attributed to their values of gross calorific value 30 Mj/kg-(moist-mineral-matter-free; mmmf), fixed carbon 45% (dry-mineral-matter-free; dmmf) and volatile matter 54.8% dmmf. Elemental ratio of H/C versus O/C indicate that majority of the studied Maghara coal samples occupy the area of vitrinite genesis pathway on Van-Krevelen diagram, and within the area of per-hydrous in Seyler chart of dominated anoxic condition. Studied coal seam is a type III kerogen corresponding to humic characteristic, within the immature and mature zones of coalification. 相似文献
29.
Mohamed A. Kassab Nader H. El Gendy Shadia A.M. Saad Mamdouh G. Shehata Mohamed M. Gadallah Mariline W. Badaro 《Egyptian Journal of Petroleum》2018,27(4)
Sixty-two samples were collected from the five formations at Um Bogma area, (Southwest Sinai, Egypt). Nine samples were collected from Sarabit El Khedim Formation, ten samples were collected from Abu Hamata Formation, eighteen samples were collected from Adedia Formation, eight samples were collected from Um Bogma Formation and eighteen samples were collected from Abu Thora Formation.The Paleozoic rocks at Um Bogma area, consist mainly of sandstones, siltstones, shales, limestone and dolostones, which are unconformably overlie igneous and metamorphic rocks (granite, diorite and gneiss) of Precambrian age.The petrographic studies were applied to identify different rock units, different facies and its diagenetic history and to reveal its effect on the storage capacity properties. Different types of porosity (oversized, intergranular, fracture and vuggy porosities) have been identified based on the petrographic investigation of the studied thin sections.The Paleozoic sandstone rock samples are characterized by porosity average about 19% for Facies 1 (quartz wack) and about 18%for Facies 2 (quartz arenite) and permeability average 420?mD for Facies 1 (quartz wack) and 690?mD for Facies 2 (quartz arenite), so these rocks can be considered as good reservoir rocks. The Paleozoic carbonate rock samples (Facies 3) are characterized by poor porosity (less than 7%) and very low permeability (less than 0.5?mD), which caused by matrix and diagenetic processes and refer to bad reservoir rocks.Porosity can be linked to the two derived electrical properties (formation resistivity factor and electrical tortuosity) of the studied Paleozoic rocks at Um Bogma area. The electrical tortuosity has significant effects on both permeability and formation resistivity factor. The permeability decreases with increasing electrical tortuosity and the relation between both of them is inverse relationship with good coefficient of correlation. The permeability decreases with increasing electrical tortuosity and the relations between both of them are inverse relationships with high coefficient of correlation. The formation resistivity factor increases with increasing electrical tortuosity and the relations between both of them are positive relationships with a fair to very high coefficient of correlation. 相似文献
30.
Mohamed M. El Nady Fatma S. Ramadan Mahomoud M. Hammad Doaa A. Mousa Naira M. Lotfy 《Petroleum Science and Technology》2018,36(16):1250-1257
The objectives of this study are the correlation between the oil samples recovered from the Lower Cretaceous reservoirs and Lower and Upper Cretaceous source rocks. The investigated biomarkers of five oils indicated the oils were derived from mixed marine and terrigenous (lacustrine) organic matter and deposited under suboxic to anoxic conditions. These oils were also generated from source rocks of high thermal maturity at the peak oil window. So, based on the molecular indicators of organic source input,depositional environment and maturity parameters of oils and extracts, we can conclude that the oil recovered from Al Baraka oil field were derived from Lower Cretaceous source rocks especially KomOmbo (B) source rocks where it reached the oil window. Furthermore, we can indicate that the other lower Cretaceous formations as Abu Ballas Formation will have the opportunity to generate and expel oil at the deeper part of the basin as shown in the eastern part of the basin. 相似文献