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21.
《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   
22.
吐哈盆地台南凹陷吐玉克稠油油田北侧钻探的英1井,在中侏罗统西山窑组取心见到了少量含沥青砂岩。笔者利用荧光显微镜对沥青产状及荧光特征进行观察描述,结合区域地质条件的分析研究,得出了砂岩中的沥青是经过剥蚀搬运后再沉积的结论  相似文献   
23.
The most used pavement for paved roads in the world is asphalt. It is therefore important that the asphalt is as durable as possible to avoid expensive repairs of the roads. One important factor of the durability of the road is the adherence between the stones and the bitumen that holds the stones together. The affinity is tested by the so called rolling bottle test, where one put stones covered in bitumen in a bottle with water and let it roll on a bottle rolling machine. After a while the degree of bitumen coverage is estimated. In this paper, a method to estimate the degree of bitumen coverage using image analysis has been developed instead of the manual estimation that is used today. The presented method works for all colors of the stones and is based on the fact that bitumen reflects light much better than raw stones. A turntable that is rotated somewhat between images is used together with a light source in shape of a quarter of a circle to get as much specular reflections as possible. Then the amount of detected reflections is used to estimate the degree of bitumen coverage. To be able to compare the result with something close to ground truth, the method has been evaluated on lighter stones and compared with a second image analysis method that works well for lighter stones, and the results are promising.  相似文献   
24.
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   
25.
Hassan Hassanzadeh 《Fuel》2010,89(10):2822-239
In situ catalytic upgrading of heavy oil and bitumen has been suggested and tested in the laboratory for utilization of heavy oil resources. Experimental observations have demonstrated potential, so this innovative recovery technique may have a role in the development of large resources of heavy oil and bitumen. Accurate analytical and numerical modelling is necessary in order to correctly interpret experimental measurements of the in situ upgrading, leading to a better understanding and design of field-scale processes. In this paper, we present modelling and parameter estimation for ultra-dispersed catalytic upgrading experiments conducted in a batch reactor. The Monte Carlo simulation technique was used to estimate the most appropriate reaction parameters. The combination of an analytical batch reactor model and the Monte Carlo simulation technique allows for the fast generation of a large number of upgrading experiment realizations. Comparisons of analytical modelling results with the experimental measurements of the upgrading experiments at different temperatures are in close agreement. Results reveal that ultra-dispersed catalytic upgrading in a batch reactor results in a fairly high residue conversion and can potentially increase the API gravity of the produced oil.  相似文献   
26.
In this paper, the influence of some additives on the rheological and technological properties of crumb rubber modified binders has been studied. The research has been mainly focused on the degree of bitumen modification, measured as the improvement of the mechanical properties, produced by the additives used, and the storage stability of these binders at high temperature. The experimental results obtained reveal that all the polymeric additives used yield an improvement in both rheological and technological properties of the binder. The storage instability of these binders has been associated to sedimentation processes of insoluble CR particles that strongly influence the mechanical properties of the binder. The additives and processing conditions selected in this study do not completely prevent problems associated with the poor stability of CRMBs during storage at high temperature. Nevertheless, the use of polyoctenamer, FT-wax or SBS-containing additives improves CRMB stability. In this sense, similar loss tangent values were found before and after hot storage of these binders.  相似文献   
27.
It is believed that surface active materials in bitumen (asphaltenes and maltenes) are responsible for the stabilization of undesirable water-in-bitumen emulsions in several processes in the petrochemical and oil sands industries. In order to find an efficient technique to break these emulsions, complete knowledge of the interfacial properties of bitumen, maltenes and asphaltenes is required. In this work, the capability of these three fractions to form monolayers at the air-water interface and the structural conformations formed under different compression stages and different added volumes, taken from constant concentration spreading solutions, are analyzed using a Langmuir trough and Brewster angle microscopy. According to the results presented here, the three fractions form true monolayers at the air-water interface with bitumen displaying a “sponge-like” structure, asphaltenes arranging in dense islands and maltenes forming very thin flexible layers. Bitumen, asphaltenes and maltenes organize in association structures of added volume depending sizes: increasing volumes lead to increasing sizes. Compression of the monolayers also favors the formation of larger structures that, upon expansion, do not relax to their original state. This fact is responsible for the hysteresis displayed by the three fractions, being asphaltenes the fraction showing the greatest rigidity, maltenes the greatest flexibility and bitumen an intermediate behavior. Out-of-plane regions were only detected for asphaltenes, which at high surface pressures, fold and bulge up, resulting in a loss of surface active material at the air-water interface. These three-dimensional structures persist upon expansion of the film.  相似文献   
28.
李飞 《中国建筑防水》2003,(12):32-33,41
介绍了一种利用超声波原理开发的由单片机控制的非接触式测量装置,通过该装置可较方便地测量沥青贮罐的液位。  相似文献   
29.
徐克威 《石油沥青》2000,14(2):35-38,46
用合成的抗剥剂及经过改进的U-拉力实验和水煮失重实验,研究了此类抗剥剂对沥青在钢铁及石料上的粘附影响,表征此类抗剥剂的有效性,并显示沥青在钢铁上的粘附强度大于其在石料上的粘附强度。沥青的粘度大小对实验结果有影响。  相似文献   
30.
Arash Karimi 《Fuel》2011,90(3):1285-1291
The catalytic steam gasification of coke from Athabasca bitumen was investigated by thermogravimetric analysis using K2CO3 and Na2CO3 as catalysts, both of which reduced the activation energy of the reaction considerably to 1.2 × 105 J mol−1 and 1.3 × 105 J mol−1, respectively, down from 2.1 × 105 J mol−1 for the uncatalyzed reaction. The reaction rates varied with the partial pressure of steam between 60 kPa and 85 kPa consistent with a Langmuir-Hinshelwood model, but a first order equation was also sufficient given the low partial pressures. The initial rate of gasification of the coke particles correlated linearly with the estimated external surface area of the particles, as expected from a surface reaction involving a non-porous solid. The initial reaction rate increased with increasing the catalyst loading up to 2.4 (mol potassium)/kg. A portion of the catalyst penetrated into the coke, as confirmed by secondary ion mass spectroscopy analysis, where it could not promote the reaction with steam. This result was consistent with a small increase observed in the reaction rate at low catalyst loading. The shrinking core model was successful in predicting the rates at higher conversions from the initial rate data, despite increases in BET surface area with conversion.  相似文献   
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