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101.
A crude oil sample from the Assran field in the Central Gulf of Suez (Egypt) was analysed geochemically and characterized in terms of a variety of source and maturity dependent biomarkers. Biodegradation was indicated by increasing concentration ratios of Pr/n-C17 and Ph/n-C18. However, biodegradation was only slight as GC-MS analyses of the saturate and aromatic fractions showed that hopanes, steranes, aromatic steroids and polycyclic aromatic compounds including sulphur heterocycles remained intact. The sterane and hopane distributions showed a predominance of C27 steranes, a low diasterane index, an abundance of gammacerane, a high homohopane index and an oleanane index < 0.2. The results indicate that the Assran-10 crude oil was derived from a marine carbonate source deposited in a highly reducing saline environment with a high bacterial contribution, consistent with the Upper Cretaceous Brown Limestone or Lower Eocene Thebes Formation containing Type IIS kerogen. Maturity parameters based on changes in the stereochemistry at chirality centres in hopane and sterane nuclei, such as C30βα/(βα+αβ) and C31 22S/(22S+22R) hopanes and C29ββ/(ββ+αα) and C29 20S/(20S+20R) steranes, together with triaromatic sterane cracking ratios, indicate that the oil sample was marginally mature. The results also suggest that biodegradation is probably due to sulphate-reducing anaerobic bacteria.  相似文献   
102.
103.
The dynamic nature of today’s construction industry compels construction partners to seek strategies in order to improve performance. Current research introduces a performance evaluation model for construction companies in order to provide a proper tool for a company’s managers, owners, shareholders, and funding agencies to evaluate the performance of construction companies. The model developed helps a company’s management to make the right decisions. Financial, economical, and industrial data are collected from Egyptian construction companies for nine consecutive years (1992–2000). Five indices (models) are developed: company performance score, economy performance score, industry performance score, performance index, and performance grade. The models developed consider companies in four construction sectors: general building, heavy, special trade, and real estate. These models accommodate the effect of macroeconomic and industry related factors and company size on the performance evaluation. The final outcome of current research is a performance grade, which provides the performance of a construction company. The developed model is validated, which shows robust results.  相似文献   
104.
Sand Transport in Nile River, Egypt   总被引:2,自引:0,他引:2  
Measurements of bed-load and suspended-load transport rates were carried out successfully at four cross sections of the Nile River, in Egypt, along the entire length from Aswan to Cairo using a mechanical sampler called the Delft Nile Sampler. The measured transport rates were compared to similar data sets from two other large scale rivers: the Rhine-Waal River in the Netherlands and the Mississippi River in the USA. The bed-load transport rates in the Nile River and in the Rhine-Waal River are in very good agreement. Comparison of suspended transport rates in the Nile River and in the Mississippi River shows that both data sets are complementary, revealing a very consistent trend of suspended transport against current velocity; suspended transport is roughly proportional to (Vav)3?to?4. Three formulas for the prediction of bed-load transport were tested using the Nile data: Meyer-Peter–Muller, Bagnold, and Van Rijn. The prediction formula of Van Rijn produced significantly better results than the other two formulas; the average relative error was about 60%. The formula of Van Rijn was modified to extend it to conditions with slightly nonuniform sediment mixtures by introducing a correction factor for the bed shear parameter. Based on a limited number of flume experiments, the correction factor was found to be dependent on the characteristics of the sediment mixture (d10, d50, d90, and σg). Comparison of bed-load transport measured in the Nile River with computed transport rates of the modified formula showed improved results; the average relative error decreased to about 30%. The formulas of Bagnold and Van Rijn were also used to compute the suspended transport rates in the Nile River. The computed transport rates were found to be within a factor of 2 of measured values; the formula of Bagnold performed slightly better. The total load transport formula of Engelund–Hansen was also successfully used (computed values within a factor of about 2 of measured values).  相似文献   
105.
This paper investigates how arbitration is used as a dispute resolution mechanism in Egyptian large scale construction projects and what are the types of issues that construction professionals should address when they encounter claims in the Egyptian construction market. To meet the goals and objectives of this study, a research project was conducted to study the arbitration process for a dispute that was in excess of $31 million, which arose out as a result of the proceeds of a large-scale project with an original contact price of $85 million that was constructed in Cairo, Egypt. This research project analytically investigated the background of the conflicts, the arbitral proceedings, and the award issued by the arbitral tribunal. Based on such thorough study, it was concluded that arbitration did not provide a timely and cost-effective resolution for the said dispute. Moreover, the same study has raised questions in relation to the overall management of megaconstruction projects in Egypt namely: (1) the impartiality of project managers; (2) the magnitude of change orders and consequent delays; (3) the magnitude of claimed amounts; and (4) the level of management and administration of claims and disputes. It is perceived that this paper would trigger professionals to think of other suitable dispute resolution mechanisms, such as dispute review boards, for settlement of claims arising from Egyptian large scale construction projects. Furthermore, this study would be of value for contractors and owners who intend to work in the Egyptian construction market.  相似文献   
106.
A total of 2318 domestic samples of different types of fruits and vegetables were collected from eight Egyptian local markets in six different regions of the country. All samples were examined for residues of 54 pesticides, including organophosphorus, organonitrogen, organohalogen and certain pyrethroides. However, dithiocarbamates were analysed in only 318 samples. Overall, 81.5% of the samples had no detectable pesticide residues. Of the contaminated samples, 18.5% contained detectable residues and 1.9% exceeded their maximum residue limits (MRLs). Root and leafy vegetables showed the lowest contamination rates (1.9 and 4.7%, respectively), slightly exceeding the MRLs in leafy vegetables. However, fruit samples showed a slightly higher proportion of contamination than vegetables (29 and 14.3%, respectively). Fruit also exhibited a higher level of violation than vegetables (2.3 and 1.9%, respectively). The contamination and violation rates were lower than the percentages recorded in previous years' monitoring studies. Dicofol and dimethoate were the most frequently occurring pesticide residues at 5.1 and 5.0%, respectively. Dimethoate showed higher violation levels (0.69%). However, dicofol showed a slight violation rate (0.09%) which indicates good agricultural practices for dicofol use. Dithiocarbamates residues were found in 21 of the 318 samples analysed, which when expressed as a percentage contamination was 6.6%, and only one sample exceeded the MRL.  相似文献   
107.
Pronouncements about the value of information and communication technology (ICT) (hereafter traditional, new, and social media) to social movements – hyperbolic in popular media references to new and social media (e.g., Facebook revolution, Twitter revolution, etc.) – invite scholarly inquiries that critically assess the implications of these assumptions for African countries. Sensing the tendency toward technological determinism, a position which Castells warns is fraught with failure to recognize complex interactions between society and technology; authors examined popular press vis-à-vis scholarly assumptions about the value of media during social movements. Questions that critically analyze the roles and power of old versus new media in social movements should be posed particularly about 21st century iterations with citizens increasingly doubling as creators and disseminators of news and information. For example: to what extent do various media comparatively facilitate or constrain activists in social movements? How have new ICTs assisted citizen activists in circumventing the power and reach of traditional media? How have the roles of traditional versus new media in social movements been framed in the popular press and academic journals? What contextual factors (e.g., communal networks; third-party- and foreign-interventions, digital divide, etc.) may be accountable for the take-off and successes of social movements? In a continent fraught with cultural, political, and socio-economic divisions of historic proportions, authors critically assessed cases across Africa of variegated employment of old (i.e., radio, newspaper, television) and new media platforms (i.e., Facebook, Twitter, mobile telephone text messaging) by four social movements spanning 35 years. Assessments underscore citizen empowerment and multiplier capabilities of new media but affirm the value of contextual factors that minimize hyperbolic assumptions about the contribution of new media to the formation and progression of social movements.  相似文献   
108.
The organic geochemical and biomarker analyses of the Miocene source rocks of some wells in the onshore Nile Delta, suggested that the Abu Madi Formation has poor immature to marginally mature source rocks of Type III Kerogen deposited under the terrestrial environment. The Sidi Salem Formation has fair-to-good mature source rocks of producing mixed oil and gas, originating mainly from marine organic sources. The Moghra Formation has mature good source rocks for Type (II/III) kerogen, derived from organic matter and rich in both terrigeneous and marine sources. The geochemistry of condensates revealed that the Abu Madi and Moghra condensates originated from marine organic matters with little input from a terrestrial source, while Sidi Salem condensate was derived from more contribution of terrestrial organic matters. Abu Madi condensate is less mature than Sidi Salem and Moghra condensate. The geochemical thermal modeling of the Miocene source rocks indicates that the Abu Madi formations are in the early stages of hydrocarbon up until the present time, while Moghra and Sidi Salem formations are in the mature stage of hydrocarbon generation up until the present time. This indicates that the studied condensates have probably migrated from deeply buried source rocks which are at a higher level of maturity rather than from less mature source rocks in the study area.  相似文献   
109.
Palynofacies analyses were applied on ninety-one samples from the subsurface Albian – Cenomanian succession represented by Kharita and Bahariya formations, encountered in El-Noor, and South Sallum wells, located in the North Western Desert, Egypt, to visually characterize the content of dispersed organic matter, as well as, organic geochemical characterization to reveal the depositional paleoenvironments and source rock potentiality. The result recognized of five palynofacies associations in the studied interval. The deposition of Kharita Formation took place mainly in a steady and a relatively stable deltaic to marginal environment continued as well in the lower part of Bahariya Formation with minor changes. The marine influence became more common in the upper part of Bahariya Formation showing the exceptional high hydrocarbon potential recorded in the studied interval. This indicates marine transgression by the end of the early Cenomanian (Upper Bahariya) age. Samples from the Kharita Formation contain abundant brown phytoclasts which suggest gas-prone kerogen type III and IV. While Bahariya Formation includes translucent, brown cuticles and woody tracheid phytoclasts pointing to more promising gas-prone kerogen type III. The organic geochemical analysis shows poor to fair gas-prone source rock potential within the study section., Thermally, the color of the spore grains in Kharita and Bahariya formations show that dark yellow to orange, indicates immature besides their general little poor hydrocarbon generation potentiality.  相似文献   
110.
This study aims to integrate core and wire line logging data for evaluation of Kareem sandstone (Middle Miocene) in Ashrafi Field, Gulf of Suez, Egypt. The study has been carried out on seven wells ASHRAFI_A_01_ST, ASHRAFI_A_02_ST, ASHRAFI_H_IX_ST2, ASHRAFI_I_1X_ST, ASHRAFI_K_1X, ASHRAFI_SW_04, ASHRAFI_SW_06, by using wire line logging data and core data. The interpretation of these data has been done by using Interactive Petrophysics software.The Net pay thickness ranges between 17?ft to about 110?ft, porosity varies from 13% to 26%, permeability from 125?mD to about 960?mD, water saturation from 19% to about 50% and shale content from about 18% to about 56%. The interpretation of the Kareem sandstone (core data for ASHRAFI_SW_04 well) indicates that the average core porosity value is about 17% and the average core permeability is about 800?mD, which indicate a suitable reservoir. The porosity increases with the increasing of the permeability and the relationship between them has good correlation coefficient of 0.81 for wire line logging data set and 0.85 for core data set. These relations can be used to determine permeability from porosity for sandstone of Kareem Formation.The new development area for Ashrafi Field can be determined where there are two zones: one in the Middle and the other in South west. Stratigraphic correlation chart shows that, the Kareem Formation thickness varies laterally in Ashrafi field so, the new well location could be determined perfectly. The integration between well logging data and core data are very important tools to evaluate the degree of heterogeneity in the Kareem sandstone and storage capacity properties as well as the zone of interest of productivity and perforation.  相似文献   
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