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51.
The presence of sand in heavy oil production is known to enhance oil recovery. Sand can also be detrimental depending on the properties of the sand–water interface. In this process, the water soluble material interacts with both sand and oil droplets and affects emulsion stability. The formation and stability of heavy oil‐in‐water emulsions during turbulent flow using batch process stirred‐tank mixing of oil, sand, and water were investigated at three pH. Size distributions were measured by laser diffraction. High‐speed video photomicrography was used to observe the process during mixing. Results showed that the presence of sand enhanced formation of stable, fine emulsion at basic pH 8.5. When the pH of the water was reduced below 6.5 both sand and droplets surface properties changed, the emulsions became less stable and coalescence was apparent. The sand grains acted as coalescers at low pH and enhanced breakage at high pH. © Her Majesty the Queen in Right of Canada, as represented by the Minister of Natural Resources, 2008 AIChE J, 2009 相似文献
52.
Mounir Djellab Hamza Bentrah Abdelouahad Chala Hicham Taoui Slimane Kherief Bouzid Bouamra 《工业材料与腐蚀》2020,71(8):1276-1288
The synergistic effect of bark resin of Schinus molle (BRSM) and iodide ions in 0.5 M sulfuric acid has been studied for the first time by potentiodynamic polarization and electrochemical impedance spectroscopy measurements; also, the surface morphology has been analyzed by scanning electron microscopy–energy-dispersive X-ray spectroscopic analysis in the present work. The results show that the BRSM and iodide ions have an evident synergistic inhibition effect in a 0.5-M sulfuric acid solution. The adsorption of the BRSM/iodide ion system follows the Langmuir adsorption isotherm and acts as a mixed-type inhibitor in sulfuric acid. The BRSM/iodide ion system is an effective inhibitor for API5L X70 pipeline steel in the 0.5-M sulfuric acid solution. The maximum percentage inhibition efficiency is equal to 99% at 1 g/L BRSM + 2 mM KI. 相似文献
53.
This paper presents a new method for copy-move forgery detection of duplicated objects. A bounding rectangle is drawn around the detected object to form a sub-image. Morphological operator is used to remove the unnecessary small objects. Highly accurate polar complex exponential transform moments are used as features for the detected objects. Euclidian distance and correlation coefficient between the feature vectors are calculated and used for searching the similar objects. A set of 20 forged images with duplicated objects is carefully selected from previously published works. Additional 80 non-forged images are edited by the authors and forged by duplicating different kinds of objects. Numerical simulation is performed where the results show that the proposed method successfully detect different kinds of duplicated objects. The proposed method is much faster than the previously existing methods. Also, it exhibits high robustness to various attacks such as additive white Gaussian noise, JPEG compression, rotation, and scaling. 相似文献
54.
Radiochemistry - Wadi El Reddah has radiation exposure due to the presence of different types of complexed rocks along with a huge sector of Hammamat sedimentary rocks, monzongranites of Gabal El... 相似文献
55.
Hamza Saidi Walid Aloui Abdelaziz Bouazizi 《Journal of Materials Science: Materials in Electronics》2018,29(21):18051-18058
The electrical proprieties of poly (3-hexylthiophene): Silicon nanowires (P3HT: SiNWs) nanocomposite was investigated by impedance spectroscopy technique. The effect of bias voltage under and without illumination was discussed. Indeed, the imaginary part of the impedance shows a high relaxation frequency related to Maxwell–Wagner–Sillars (MWS) polarization. The relaxation time was found in the range of ms and it was shifted towards high frequency with increasing the bias voltage especially at 0.6 V At bias voltage equal to Vth and under illumination, the conductivity increases because the trapped charges acquire the necessary energy to escape from the interface and the hopping time found was reduced. This indicates a change of the conduction mechanism. The Cole–Cole diagram was excellently fitted through an equivalent circuit including a chemical capacitance Cµ, a contact electrical resistance Rs and recombination resistance Rp. 相似文献
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The performances of the multivariate techniques are directly related to the variable selection process, which is time consuming and requires resources
for testing each possible parameter to achieve the best results. Therefore, optimization methods for variable selection process have been proposed in the
literature to find the optimal solution in short time by using less system resources. Contrast enhancement is the one of the most important and the parameter
dependent image enhancement technique. In this study, two optimization methods are employed for the variable selection for the contrast enhancement
technique. Particle swarm optimization (PSO) and artificial bee colony (ABC) optimization methods are implemented to the histogram stretching technique
in parameter selection process. The results of the optimized histogram stretching technique are compared with one of the parameter independent contrast
enhancement technique; histogram equalization. The results show that the performance of the optimized histogram stretching is better not only in distorted
images but also in original images. Histogram equalization degraded the original images while the optimized histogram stretching has no effect due to
being an adaptive solution. 相似文献
60.
Malik Javed Akhtar Zahur Ahmad Rashid Amin Sultan H. Almotiri Mohammed A. Al Ghamdi Hamza Aldabbas 《计算机、材料和连续体(英文)》2020,65(3):2639-2663
A large amount of data is present on the web which can be used for useful
purposes like a product recommendation, price comparison and demand forecasting for a
particular product. Websites are designed for human understanding and not for machines.
Therefore, to make data machine-readable, it requires techniques to grab data from web
pages. Researchers have addressed the problem using two approaches, i.e., knowledge
engineering and machine learning. State of the art knowledge engineering approaches use
the structure of documents, visual cues, clustering of attributes of data records and text
processing techniques to identify data records on a web page. Machine learning
approaches use annotated pages to learn rules. These rules are used to extract data from
unseen web pages. The structure of web documents is continuously evolving. Therefore,
new techniques are needed to handle the emerging requirements of web data extraction.
In this paper, we have presented a novel, simple and efficient technique to extract data
from web pages using visual styles and structure of documents. The proposed technique
detects Rich Data Region (RDR) using query and correlative words of the query. RDR is
then divided into data records using style similarity. Noisy elements are removed using a
Common Tag Sequence (CTS) and formatting entropy. The system is implemented using
JAVA and runs on the dataset of real-world working websites. The effectiveness of
results is evaluated using precision, recall, and F-measure and compared with five
existing systems. A comparison of the proposed technique to existing systems has shown
encouraging results. 相似文献