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21.
In this paper, a new energy management algorithm has been suggested for the ships connected with alternative energies considering the smart electricity grid features. The algorithm focuses on the use of optimum energy source on the shipboard based on the priorities of authorities such as the most economic, environmental, or both criteria at the ports. The algorithm is performed in MATLAB, and several case studies are simulated to validate the results. The 5 maritime nations, which are at different regions: United States, Belgium, Turkey, China, and Australia, are taken into account in the case studies. The actual data of a bulk carrier ship have been used to achieve tangible results in the simulations. The results of the case studies are compared to determine the changes of energy cost and released emission to meet demand of electricity on the ships. Capital cost of the proposed concept is also given to make an economic evaluation. The results show that the ship energy management algorithm provides the significant economic and environmental advantages. This paper aims to contribute to the importance of the ships in the smart electricity grid concept for the maritime and electricity sector representatives. 相似文献
22.
Arici Muhammet Ozulku Gorkem Yildirim Rusen Metin Sagdic Osman Durak M. Zeki 《Food science and biotechnology》2018,27(2):499-508
Food Science and Biotechnology - In this study, yeasts were isolated and characterized from twelve traditional sourdough samples which belongs to Black Sea and Aegean regions of Turkey. Twenty six... 相似文献
23.
Rubber pad forming is studied numerically and experimentally to fabricate interconnectors for solid oxide fuel cells (SOFCs) from thin Crofer sheets instead of classical thick ones with machined flow channels. In the theoretical program, the effects of the rib angle, rib width and channel depth on the formability are numerically investigated and optimized as 120°, 0.5 mm and 0.5 mm, respectively. In addition, flow simulations are performed to analyze the flow uniformity in the flow-field for the final geometry and homogenous reactant distributions are observed. In the experimental program, the interconnector with numerically optimized geometry is successfully manufactured by rubber pad forming, trimming, piercing and spot welding processes. This interconnector is used to build a two-cell stack. A similar stack is also constructed with a conventional interconnector for comparison. The performances of these stacks are measured at different operating temperatures. According to the simulation and experimental results, rubber pad forming is found to be a highly effective manufacturing route to fabricate SOFC interconnectors from thin Crofer sheets, providing higher specific and volumetric power density values for SOFC stacks compared to those of conventional stacks with interconnectors having machined flow channels. 相似文献
24.
Selçuk Yildirim Bettina Röcker Marit Kvalvåg Pettersen Julie Nilsen‐Nygaard Zehra Ayhan Ramune Rutkaite Tanja Radusin Patrycja Suminska Begonya Marcos Véronique Coma 《Comprehensive Reviews in Food Science and Food Safety》2018,17(1):165-199
The traditional role of food packaging is continuing to evolve in response to changing market needs. Current drivers such as consumer's demand for safer, “healthier,” and higher‐quality foods, ideally with a long shelf‐life; the demand for convenient and transparent packaging, and the preference for more sustainable packaging materials, have led to the development of new packaging technologies, such as active packaging (AP). As defined in the European regulation (EC) No 450/2009, AP systems are designed to “deliberately incorporate components that would release or absorb substances into or from the packaged food or the environment surrounding the food.” Active packaging materials are thereby “intended to extend the shelf‐life or to maintain or improve the condition of packaged food.” Although extensive research on AP technologies is being undertaken, many of these technologies have not yet been implemented successfully in commercial food packaging systems. Broad communication of their benefits in food product applications will facilitate the successful development and market introduction. In this review, an overview of AP technologies, such as antimicrobial, antioxidant or carbon dioxide‐releasing systems, and systems absorbing oxygen, moisture or ethylene, is provided, and, in particular, scientific publications illustrating the benefits of such technologies for specific food products are reviewed. Furthermore, the challenges in applying such AP technologies to food systems and the anticipated direction of future developments are discussed. This review will provide food and packaging scientists with a thorough understanding of the benefits of AP technologies when applied to specific foods and hence can assist in accelerating commercial adoption. 相似文献
25.
26.
Fazil?CanbulutEmail author Cem?Sinano?lu ?ahin?Yildirim 《Journal of Mechanical Science and Technology》2004,18(3):432-442
This paper presents a neural network predictor for analysing rigidity variations of hydrostatic bearing system. The designed
neural network has feedforward structure with three layers. The layers are input layer, hidden layer and output layer. Two
main parameter could be considered for hydrostatic bearing system. These parameters are the size of bearing pocket and the
orifice dimension. Due to importancy of these parameters, it is necessary to analyse with a suitable optimisation method such
as neural network. As depicted from the results, the proposed neural predictor exactly follows experimental desired results. 相似文献
27.
Musa Yildirim Dursun Özyürek Metin Gürü 《Fullerenes, Nanotubes and Carbon Nanostructures》2016,24(7):467-473
In this study, the effect of CNT amount in Al-CNT composites produced by adding carbon nanotube (CNT) to 7075 Al alloy in various amounts on microstructure and wear behaviors of aluminum matrix composites was investigated. CNT was added to 7075 Al alloy powder at five different amounts. The powders were mechanically milled for 2 hours. Mechanical milled powders were cold pressed and then pre-shaped by hot pressing. Pre-shaped samples were sintered for 1 hour under 10?6 millibar in 580°C. Microstructure examinations, hardness measurements, and wear tests were carried out. The results show that CNT's in the microstructure were agglomerated as nanotube amount increases and there was no uniform distribution. The highest hardness value was obtained in AMC reinforced with 1% CNT while it is seen that hardness of the composite decreases and weight loss increases as CNT amount increases. 相似文献
28.
A UV-curable acrylated urethane prepolymer was synthesized from tolylene-2,4-diisocyanate (TDI), a polyether polyol (Arcol 1131) and endcapped with 2-hydroxyethyl methacrylate (HEMA) by addition reaction in the presence of dibutyltin dilaurate as catalyst. UV curing was performed with either diethylene glycol diacrylate or thiodiethylene glycol diacrylate as reactive diluent. The effects of reactive diluent types, their concentrations and the humidity of environment on mechanical properties of cured films were investigated. Changes in the tensile strength, elongation and Young's modulus values of the cured films upon addition of reactive diluents with different concentrations were related to the effect of the diluent on the crosslinking density of cured films. The increase of relative humidity from 50 to 95% caused a decrease of tensile strength and Young's modulus values of cured films. It is proposed that the decrease of these physical properties in high relative humidity is due to the formation of hydrogen bonding in polymer chains caused by water molecules. 相似文献
29.
Chitosan is synthesized by deacetylating chitin with NaOH solution under microwave irradiation. The process describes a rapid
synthesis procedure in comparison to conventional methods. The microwave-synthesized chitosan was characterized by Ninhydrin
test, Fourier transform-infrared spectroscopy and X-ray diffraction measurements. The experimental results show that the degree
of deacetylation increased with increasing irradiation time. A degree of deacetylation of 85.3% was achieved after irradiating
chitin with 45% NaOH solution in a microwave for 5.5 min at 900-watt power. This method can be very useful for synthesizing
low molecular weight chitosan with rapid and clean chemistry. 相似文献
30.
A new computational method based on the J k -integral is put forward for the purpose of conducting fracture analysis of orthotropic materials subjected to hygrothermal stresses. By utilizing the constitutive relations of plane orthotropic hygrothermoelasticity, an alternative expression for the J k -integral is derived to replace the general limit definition. A numerical procedure is developed and integrated into a finite element analysis software to implement the proposed form of the J k -integral. Temperature and specific moisture concentration fields, which are required in fracture calculations, are also computed through finite element analysis. Numerical results are generated by considering an embedded crack in a polymer matrix fibrous composite laminate, that is subjected to steady-state hygrothermal loading. Comparisons of the mixed-mode stress intensity factors computed by the J k -integral based method to those evaluated via the displacement correlation technique demonstrate that, the proposed form of the J k -integral is domain independent and leads to numerical results of high accuracy. Presented parametric analyses illustrate the influences of the fiber volume fraction and the crack location on the modes I and II stress intensity factors, the energy release rate, and the T-stress. 相似文献