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41.
Ziad Mansour Mohd Raihan Taha Zamri Chik 《Bulletin of Engineering Geology and the Environment》2009,68(1):97-106
Problems have occurred with dykes constructed on the Lisan Marl to retain brine pumped from the Dead Sea, which is chemically
processed to produce potash. In this study the engineering behavior, collapse potential and compressibility of the Lisan Marl
were assessed by undertaking laboratory tests with both natural, distilled water and brine as the media. The results showed
that the liquid limit and fine particles increased when the soil was mixed with fresh/distilled water compared with brine
water. The soil can be classified as highly compressible with a low undrained shear strength. In terms of collapsibility,
the soil could be classified as slightly collapsible upon inundation with distilled water and moderately collapsible when
soaked in Dead Sea brine. The results are important when determining the height and nature of the dykes.
相似文献
42.
A novel methodology for the solvent free auto-oxidation of methylbenzenes under mild conditions is disclosed. The new scheme is based on a combination of metallic salt (cobalt chloride) and a quaternary ammonium phase transfer catalyst (didecyldimethylammonium bromide) which together form a complex soluble catalyst in the organic phase. Major reaction parameters are studied and optimized and the procedure is applied for the conversion of several substituted toluenes to the corresponding benzoic acids in excellent isolated yields. 相似文献
43.
Microalloyed steels are characterised by their mechanical properties. Nowadays, they are used in a wide range of applications. The convenience and simplicity of hardness tests permit to obtain economically and rapidly information on the structure of steels and control their treatments. This study has been carried out to derive equations for prediction of the mechanical properties of microalloyed steels by hardness measurement. With this objective, V‐ and Ti‐microalloyed plain carbon steel bars were melted, hot rolled, heat treated and machined for the measurement of their mechanical properties and to reach a correlation between both ultimate tensile strength, yield strength and uniform elongation and Vickers hardness. The obtained data were treated using different mathematical fittings. They are mathematically treated as groups according to the heat treatment processes and as one group. The derived equations show good agreement with each other and with most of the little relations found in the literature. General equations for deducing mechanical properties values from the easily measured Vickers hardness values were derived. The equations derived from one group without regarding the treatment processes are more reliable. 相似文献
44.
Mohamed A. Taha Nahed A. El-Mahallawy Rawia M. Hammouda Sherif I. Nassef 《Journal of Coatings Technology and Research》2010,7(6):793-800
Although magnesium alloys have the advantage of high specific strength, they have poor atmospheric corrosion resistance. An
important method of improving the corrosion resistance is by applying a coating layer. In this work, the physical vapor deposition
(PVD) technique is used for coating a magnesium (Mg) AZ31 sheet substrate with a thin layer of high purity aluminum (Al) and
Al–12.6% Si. Aluminum is expected to be suitable as a coating layer on Mg sheets, due to its corrosion resistance and its
formability. Before coating, the substrate was subjected to several consecutive surface preparations, including sand-blasting,
mechanical grinding, mirror-like polishing, ultrasonic etching, and finally ion etching by magnetron sputtering (MS). PVD
coating was conducted using a PVD machine with max electron beam power and voltage of 100 kW and 40 kV, respectively. This
was either with or without plasma activation, and with variable substrate speeds ranging between 10 and 70 mm/s. During MS
ion etching and coating, the substrate temperature increased. The substrate temperature increased with the application of
plasma activation and with lower substrate speeds. The coating-layer thickness varied inversely with substrate speed. A thinner
coat with finer morphology was obtained in the case of plasma activation. Other results included coating layer characteristics,
diffusion between the AZ 31 substrate and the Al coating layer, adhesion of the coating layer to the substrate, and corrosion
resistance by a humidity test. 相似文献
45.
Muhammad H. Alu'datt Taha Rababah Mohammad N. Alhamad Ghaid J. Al-Rabadi Carole C. Tranchant Ali Almajwal 《Critical reviews in food science and nutrition》2018,58(18):3209-3218
ABSTRACTPhenolic phytochemicals have become of interest due to their therapeutic potential, particularly with regards to their anti-cancer, anti-inflammatory, hypolipidemic, and hypoglycemic properties. An evolving area of research involving phenolics in foods and their products pertains to the functional, biological, and nutritional consequences resulting from the binding between certain phenolic compounds and the macronutrient and micronutrient constituents of foods. The goal of this review is to provide a summary of studies investigating endogenous phenolic interactions with major components in food systems, including carbohydrates, proteins, lipids, minerals and vitamins, with a focus on the phenolic compounds and nutrients in oil-bearing plants. Another major objective is to provide a comprehensive overview of the chemical nature of phenolic interactions with food constituents that could affect the quality, nutritional and functional properties of foods. Such information can assist in the discovery and optimization of specific phenolic complexes in plant-based foods that could be utilized towards various applications in the food, nutraceutical and pharmaceutical industries. 相似文献
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48.
Ahmed I. A. Abd El-Mageed Ahmed Esmail Shalan Lamiaa A. Mohamed Hisham A. Essawy Fouad Taha Amro K. F. Dyab 《Polymer Engineering and Science》2021,61(1):234-244
Styrene as a monomer was emulsified in water using several magnetite nanoparticles concentration and pH values. Emulsified styrene drops were used as templates for polymerization, in presence of water soluble free radical initiator, and formation of composite particles. Styrene template drops stabilization was verified by light as well as scanning electron microscopy imaging, which ensured the participation of the particles in building up a mechanical barrier to stop oil drops coalescence. Furthermore, the produced polystyrene composites were strongly attracted to an external magnet. The difference in particles size as a function of pH was elucidated using zeta potential measurements, which indicated dominance of pH on the hydrophilicity of the particles and consequently the extent of emulsification, which in turn affected the size of the obtained microspheres. Under some circumstances, capsules were formed instead of particles. Thereby, it can be concluded that the magnetic microspheres are optimally formed at pH 2.3 independently of the magnetite content used. 相似文献
49.
Sinuhé Martínez-Martínez Nadhir Messai Frédéric Hamelin Noureddine Manamanni Taha Boukhobza 《Automatica》2014
This paper deals with the design of sequences allowing the observability of the state of a switched linear system. The proposed method, based on a graph-theoretic approach, needs only the knowledge of the system’s structure. The necessary and sufficient conditions for the existence of at least one switching sequence guaranteeing the observability of a switched structured system are provided. Such conditions are particularly intuitive and they can be implemented with classic algorithms of the graph theory. 相似文献
50.
Albadr Musatafa Abbas Abbood Tiun Sabrina Ayob Masri AL-Dhief Fahad Taha Omar Khairuddin Maen Mhd Khaled 《Multimedia Tools and Applications》2022,81(17):23963-23989
Multimedia Tools and Applications - Automatic Emotion Speech Recognition (ESR) is considered as an active research field in the Human-Computer Interface (HCI). Typically, the ESR system is... 相似文献