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91.
For a long time, Cannabis sativa has been used for therapeutic and industrial purposes. Due to its increasing demand in medicine, recreation, and industry, there is a dire need to apply new biotechnological tools to introduce new genotypes with desirable traits and enhanced secondary metabolite production. Micropropagation, conservation, cell suspension culture, hairy root culture, polyploidy manipulation, and Agrobacterium-mediated gene transformation have been studied and used in cannabis. However, some obstacles such as the low rate of transgenic plant regeneration and low efficiency of secondary metabolite production in hairy root culture and cell suspension culture have restricted the application of these approaches in cannabis. In the current review, in vitro culture and genetic engineering methods in cannabis along with other promising techniques such as morphogenic genes, new computational approaches, clustered regularly interspaced short palindromic repeats (CRISPR), CRISPR/Cas9-equipped Agrobacterium-mediated genome editing, and hairy root culture, that can help improve gene transformation and plant regeneration, as well as enhance secondary metabolite production, have been highlighted and discussed.  相似文献   
92.
93.
The liquid phase adsorption process was studied on nano-zeolite Ba-X for separating para-xylene from a feed mixture containing all C8 aromatics. Nano-zeolite Ba-X with different ratios of SiO2/Al2O3 was synthesized through hydrothermal process and ion-exchanged with barium. The product was characterized by X-ray diffraction, scanning electron microscopy (SEM), nitrogen adsorption and in situ Fourier transform infrared (FTIR) spectroscopy. The adsorption process was carried out in a breakthrough system at temperature range of 120–160 °C under 4–7 atm pressure. The influence of nano-zeolite water content on the separation process was studied. The optimization of adsorption process was also investigated by changing the operation conditions. The adsorption isotherm for all C8 aromatic isomers and also desorbents indicated the typical Langmuir type. The selectivity factor of adsorbent for para-xylene and the adsorption capacity at saturation of the different adsorbate samples with each component from C8 aromatic mixture were determined. It was observed that the selectivity of para-xylene increased by barium ion-exchange of cationic sites in nano-zeolite X and the adsorbent selectivity for para-xylene relative to each of meta-xylene, ortho-xylene and ethyl-benzene under the optimum conditions was found to be 7.191, 2.819 and 3.745, in the order given. It was also studied the influence of desorbent type on its selectivity for para-xylene compared to each isomer from the C8 aromatic mixture.  相似文献   
94.
During the last decade, the market penetration of photovoltaic (PV) technology has been increased tremendously worldwide. In the EU context, following the quick development in German and Spanish PV sector, Italy is currently one of the most interesting market. In view of these facts, it is strategic to perform detailed technical and economic analyses to establish energy performances and profitability of the PV plants, depending on their configurations. In particular, in addition to the selection of main components, such as inverters and modules, which are now characterized, on average, by good performance levels, the debate on the support structures is still open. In detail, the choice may fall, for example, on traditional fixed structures or on one/two axis tracking systems, that could ensure best productivity per unit of power, but also are typically characterized by higher complexity and land‐occupation factors than the first ones. The purpose of this work is to carry out performance analyses on the most widespread plant configurations, taking into account different Italian climatic contexts, considering technical, energetic, and economic points of view. With this aim, different types of components (modules and inverters) and ground‐mounting structures (fixed, one‐axis, two‐axis) have been evaluated. Subsequently, their obtainable performances have been estimated in three different locations (Milano, Roma, Palermo) that have been considered representative of average irradiation levels available in Italy. Analyses have been carried out by computer simulations, through two consequent levels of detail, highlighting the main performance influence‐factors. In conclusion, the final profitability of each analyzed configuration has been evaluated, giving a reliable indication on their effective economic advantages. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
95.
This paper presents an experimental research carried out for testing the simple calculation models presented in EN 1993‐1‐2 for the determination of the fire resistance of steel structures, as well as the models for calculating the development of temperature in the structure. The analysis was carried out for the simple heat transfer models in protected and unprotected steel elements, for the basic parameters of reduction of mechanical properties of steel at high temperatures, and for simple calculation models for determining fire resistance of elements subjected to vertical force in combination with and without the action of the axial force.  相似文献   
96.
In this research, dextran nano?bres were produced as novel carriers for entrapment of vitamin E. Morphological studies indicated that developed fine fibres were in the nano range without spherical beads. Thermal behaviour, chemical structure, and crystalline structure of vitamin E-loaded nanofibres were analysed by differential scanning calorimetry, Fourier transform infrared spectroscopy, and X-ray diffraction which showed that the vitamin was well incorporated within the amorphous structure of fibres without chemical interactions. Nanofibres were used for fortification of cheese. Sensory analysis of the fortified product was performed which showed better acceptability and texture of cheese containing nanofibres in comparison to blank and direct fortified samples. Nanofibres showed the capability of holding water and thus increasing cheese firmness. The release of vitamin E in gastrointestinal media showed that about 14% of vitamin could be released in gastric media and about 30% released in intestinal media. Finally, the results revealed that electrospinning can be used for production of dextran ultrathin fibres to entrap hydrophobic compounds with high potential for design of novel functional foods.  相似文献   
97.
The eutectic micro-constituent in SnAgCu solder governs the deformation behavior of the joint as it shows better deformation resistance than the Sn dendrites and occupies a high volume percentage of the whole solder. The main scope of this study is to develop a three-dimensional (3-D) homogenization model taking into account the microstructural evolution in the eutectic micro-constituent of SnAgCu solder in order to simulate the change in mechanical behavior of the joint caused by isothermal ageing. For this purpose, 3-D configurations of Ag3Sn and Cu6Sn5 intermetallic compounds (IMCs) in near-eutectic SnAgCu solder are visualized in the as-soldered condition and after ageing by focused ion beam/scanning electron microscopy tomography. The tomographic images are used to generate feature-preserving finite element meshes of the actual microstructures. The representative volume element size and constitutive behavior of the eutectic mixture in the two conditions are determined by a numerical homogenization procedure. The results show a considerable reduction in the yield stress level of the eutectic micro-constituent after ageing of the solder joint. It is shown that the increase in the inter-particle spacing and decrease in the aspect ratio of IMCs due to ageing cause a significant change in the strain distribution in the tin matrix, which leads to a lower contribution of IMCs in load-sharing and yield strength of aged solder. The elastic–plastic properties of as-soldered and aged eutectic mixtures are determined by nanoindentation. The results of homogenization are validated through comparison with experimental results and prediction of the dislocation detachment theory.  相似文献   
98.
This work focuses on multi-stimuli-responsive materials with distinctive abilities, that is, color-changing and shape-memory. Using metallic composite yarns and polymeric/thermochromic microcapsule composite fibers, processed via a melt-spinning technique, an electrothermally multi-responsive fabric is woven. The resulting smart-fabric transfers from a predefined structure to an original shape while changing color upon heating or applying an electric field, making it appealing for advanced applications. The shape-memory and color-changing features of the fabric can be controlled by rationally controlling the micro-scale design of the individual fibers in the structure. Thus, the fibers’ microstructural features are optimized to achieve excellent color-changing behavior along with shape fixity and recovery ratios of 99.95% and 79.2%, respectively. More importantly, the fabric's dual-response by electric field can be achieved by a low voltage of 5 V, which is smaller than the previously reported values. Above and beyond, the fabric is able to be meticulously activated by selectively applying a controlled voltage to any part of the fabric. The precise local responsiveness can be bestowed upon the fabric by readily controlling its macro-scale design. A biomimetic dragonfly with the shape-memory and color-changing dual-response ability is successfully fabricated, broadening the design and fabrication horizon of groundbreaking smart materials with multiple functions.  相似文献   
99.
Haghani  Milad  Varamini  Pegah 《Scientometrics》2021,126(8):7005-7050
Scientometrics - Following the outbreak of SARS-CoV-2 disease, within less than 8 months, the 50 years-old scholarly literature of coronaviruses grew to nearly three times larger...  相似文献   
100.
Clean Technologies and Environmental Policy - High population growth rate and the limited non-renewable energy sources such as fossil fuels have made different challenges for the energy supply in...  相似文献   
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