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11.
复杂地基对西龙池面板堆石坝三维应力及变形的影响研究   总被引:1,自引:1,他引:0  
西龙池抽水蓄能电站的下水库大坝为沥青混凝土面板堆石坝,坝址碎石料覆盖层较深,且河床基岩面向下游倾斜,大坝设计中如何合理利用坝基覆盖层碎石料并减少坝基开挖量是十分重要的问题。本文采用清华非线性解耦K-G模型,进行大坝三维非线性有限元分析,研究了蓄水期坝体变形特点及下游坡及坝趾区坝基的稳定问题,并提出相应的工程措施。  相似文献   
12.
含氚废水水泥固化实验研究   总被引:2,自引:0,他引:2  
研究用水泥固化处理氚废水,并选择了最佳配方:水与灰的重量比=0.45~0.5,水泥与石膏重量比=5∶1。用IAEA推荐的方法做浸出实验。为了减少水泥固化体中氚的浸出量,实验了几种涂层材料。沥青涂层可将固化体氚的浸出率降低1~2个量级。  相似文献   
13.
简要介绍了中石化股份公司抚顺石油化工研究院近几年来在石油沥青类产品的生产和应用技术开发方面所取得的主要成果,包括高等级道路沥青、改性沥青、水工沥青、乳化沥青、彩铺胶结料及其它特种沥青等产品的开发与应用情况。在近几年的研究开发工作中.该院密切注意石油沥青技术的发展动向与市场应用情况,并结合国内外原油情况,开发了包括高等级道路沥青在内的系列沥青产品生产技术。这些沥青类产品已经应用于各类工程建设中。  相似文献   
14.
Abstract

The high cost of remediating asphaltene deposition in crude oil production and processing has necessitated the development of test methods for determining the stability of asphaltenes in crude oils. In the current work, the stability of asphaltenes in crude oils of varying API gravity is predicted using the Oliensis Spot Test, the Colloidal Instability Index, the Asphaltene–Resin ratio, and a solvent titration method with NIR solids detection. The test methods are described in detail and experimental data from them presented. The experimental stability data were validated via correlation with field deposition data. The effectiveness of the various tests as predictors of the stability of asphaltenes in oils is discussed. The Colloidal Instability Index and the solvent titration method were found to predict a crude oil's propensity towards asphaltene precipitation better than both the Asphaltene–Resin ratio and the Oliensis Spot Test. For oils with low asphaltene content where most stability tests fail, live oil depressurization is proposed as the test for predicting the stability of asphaltenes.  相似文献   
15.
Abstract

Oil sand, which is found in various deposits around the world, consists mostly of sand, surrounded by up to 18 wt% bitumen. The largest deposits known are situated in northern Alberta, Canada, where reserves of bitumen are estimated to be 1.7 trillion barrels. Bitumen is similar to heavy oil, but with much higher viscosity and density. The two main commercial oil sand operations in Alberta are surface mines and use aqueous flotation of the bitumen to separate it from the rest of the oil sand. Under optimal conditions up to 95% of the bitumen can be recovered, but occasionally ores are mined that create problems in extraction, and recovery can drop to 70% or less. This article discusses the microscopic morphologies of various bitumen and heavy oil streams and their relationship to processing problems. The results of extensive microscopic work have demonstrated that the bitumen in an oil sand ore is the phase most susceptible to oxidation and that the resulting changes manifest themselves in particular microscopic structures. The presence and type of these structures can be related to the processing behavior of oil sand ores. Morphological features found in froths from commercial operations are similar to those found in froths from laboratory-prepared samples. The morphological features found in froths of oxidized ores have been categorized and quantified for a variety of samples and are referred to as degraded bitumen structures. Experiments in which fresh oil sand ores were subjected to low-temperature oxidation showed that bitumen froth morphology changed dramatically compared to that of nonoxidized ores for identical bulk compositions and extraction water chemistries.  相似文献   
16.
    
Abstract

In this study, the chemical and middle and low temperature functional analysis of bitumen modified by waste polybutadiene rubber (PBR) polymer is conducted. The results suggest that the addition of waste PBR polymer to the pure bitumen increases its resistance to fatigue, low temperature cracking, aging and oxidation. The results of this study demonstrate that waste PBR polymer has storage stability. When PBR polymer is added to the pure bitumen by at least 1%, its low temperature performance improves from −22 °C to −28 °C. The results of FTIR and XRD show that there is good agreement between the results of these techniques and other results of middle and low temperature functional analysis, which can help assess the results accurately at macromolecular level. This study is an innovative research because it analyzes the middle and low temperature performance of waste PBR polymer in the bitumen modification along with chemical analysis using FTIR and XRD methods for the first time in the world.  相似文献   
17.
    
Most parts of Iran have completely different climates in different seasons of year. In other words, in summer it is very warm and in winter it becomes very cold. Achieving modified bitumen that could function adequately in both high and low temperature has always been under attention of researchers. One of bitumen modifiers is styrene butadiene styrene polymer. Because bitumen modified by styrene butadiene styrene does not show expected field function in both high and low temperatures, largely due to phase separation of bitumen and polymer, in the present study it has been tried to analyze the low-temperature function of bitumen modified by combining nano-SiO2 and styrene butadiene styrene polymer. The study reveals that adding nano-SiO2 by 3% and 4% of bitumen weight to the double combination of bitumen and styrene butadiene styrene polymer has improved its function in low temperature. This study has innovation as it deals with the analysis of low temperature function of nano-SiO2 and SBS in modification of bitumen for the first time in the world.  相似文献   
18.
    
Uniform distribution of liquid feed on fluidzed bed increase yield on valuable of products and improves operability in the process of fluid coking, and it is of crucial improtance to optimize the contact between the injected liquid and the bed solids. The moisture in fluidized bed is divided into three groups: (a) free moisture, (b) microagglomerates, and (c) macroagglomerates. The goal of this study was to develop a rapid and reliable experimental technique to assess the liquid-solid contact efficiency resulting from the injection of gas-atomized liquid feed. Immediately after the injection of liquid through an atomization nozzle, the triboelectric charges accumulated on the particles migrated to a grounded electrode through the paths offered by the conductive liquid. The methods based on the in situ measurements of the bed conductance varies with time, therefore, use to detect the liquid distribution on different agglomerates, and the air-liquid ratio effect of nozzle is also presented.  相似文献   
19.
    
《能源学会志》2020,93(6):2456-2463
This work focuses on bitumen slow pyrolysis. Mass and energy yields of oil, solid and gas were obtained from pyrolysis experiments using a semi-batch reactor in a nitrogen atmosphere, under three non-isothermal conditions (maximum temperature: 450 °C, 500 °C and 550 °C). The effect of temperature on the product yields was discussed. The gas compositions were analysed using gas chromatography (GC) and the heating value of oil and solid residue was also measured. Using a thermo-gravimetric analyser, kinetic parameters were evaluated through Ozawa-Flynn-Wall (OFW) method. Results showed that oil yield is maximum at 500 °C (50%). Moreover, gas yield increased with increasing pyrolysis temperature from 18% to 36%. On the other hand, solid yield showed an opposite trend: it decreased from 39% to 32%. As regard energy yields, they showed a similar trend with the mass ones. H2, CH4, C2H4, C2H6 and C3H8 are the main components of the produced gas phase. It has been noticed that the recovery of bitumen to liquid oil through pyrolysis process had a great potential since the oil produced had high calorific value comparable with commercial fuels.  相似文献   
20.
结合某省道旧有沥青结构道路改造采用的冲击压实技术,结合一系列实测结果,介绍了冲击压路机冲击压实机理,探讨并建议了在不同道路病害成因的情况下,冲击压路机型号选择、冲压效果的检测标准确定、冲压效果的评定以及相关注意事项,具有一定的参考价值。  相似文献   
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