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91.
Nanocarriers as an emerging platform for cancer therapy   总被引:6,自引:0,他引:6  
Nanotechnology has the potential to revolutionize cancer diagnosis and therapy. Advances in protein engineering and materials science have contributed to novel nanoscale targeting approaches that may bring new hope to cancer patients. Several therapeutic nanocarriers have been approved for clinical use. However, to date, there are only a few clinically approved nanocarriers that incorporate molecules to selectively bind and target cancer cells. This review examines some of the approved formulations and discusses the challenges in translating basic research to the clinic. We detail the arsenal of nanocarriers and molecules available for selective tumour targeting, and emphasize the challenges in cancer treatment.  相似文献   
92.
93.
In this study, the effect of the ARB process on the passive behavior of ultra-fine-grained 1050 aluminum alloy in a borate buffer solution(p H 6.0) has been investigated. The result of the microhardness tests revealed that the microhardness values increase with an increasing number of ARB cycles. The potentiodynamic polarization plots revealed that the higher number of cycles for the specimens proceeds with the ARB process rather than annealing yield to lower corrosion and passive current densities and more noble corrosion potential values. Moreover, electrochemical impedance spectroscopy measurements showed that increasing the number of ARB cycles offers better conditions for forming the passive films.  相似文献   
94.
Sub-critical water technique was used for simultaneous inactivation of lipase enzyme existing in rice bran and extraction of its oil in order to obtain the stabilized edible rice bran oil. Sub-critical water treatment was carried out in the temperature range between 120 and 240 °C for 10 and/or 20 min residence time in a batch reactor. The quality of the extracted oil was evaluated with respect to its total free fatty acids concentration over a 12 week period, and compared with the oil obtained by conventional extraction methods. Without sub-critical water treatment, the concentration of total free fatty acids in the rice bran significantly increased from 5.6% to 36.0%. In contrast, no increase was observed in the total free fatty acids concentration in the samples treated by sub-critical water. Experimental evidence showed that total free fatty acids concentration increased somewhat in the oils treated by conventional methods. Considering no change was observed in total free fatty acid concentration in the treated oils by sub-critical water, it was found that sub-critical water not only could efficiently extract oil from rice bran in a short residence time but also completely stabilized the extracted oil. Oil extraction yields generally increased with increases in sub-critical water treatment temperature and residence time. The highest extraction yield of oil was 249 (mg/g dry matter) obtained at 240 °C and 10 min residence time. Oil extraction by sub-critical water could be conducted in a very short residence time (10 and/or 20 min). Also, the kinetics of free fatty acids formation in untreated rice bran was investigated and developed which successfully describes the concentration of total free fatty acids in the course of rice bran storage.  相似文献   
95.
The target of this study is application of sub-critical water as a green solvent for hydrolysis of rice bran and extraction of its oil in order to obtain value-added materials. Experiments were carried out at temperatures ranging from 100 to 360 °C with 5 min residence time in a batch reactor. Four phases were isolated after reaction: hexane-soluble, acetone-soluble, water-soluble, and solid residue phases. Rice bran oil was successfully and efficiently obtained by sub-critical water extraction. Significant increases of total organic carbon (TOC) and total nitrogen (TN) in the water phase were also observed, because polysaccharides and proteins (generally bio-macro polymers) in rice bran were hydrolysed by sub-critical water. The highest yields of TOC and TN were 140 and 13 mg/g dry matter, respectively. As a result, varieties of compounds, such as amino acids, organic acids, and water-soluble saccharides, were identified in the water phase. In particular, significant amounts of water-soluble sugars (maximum yield of total sugars was nearly 190 mg/g dry matter) proved that sub-critical water was a promising medium for dissolution of biomass in water. Acetone-soluble contents were attributed to tar, carbonized biomass, and in general, water- and hexane-insoluble compounds. Solid residue consisted of mainly un-reacted rice bran and insoluble inorganic compounds.  相似文献   
96.
Momtahan O  Hsieh CR  Adibi A  Brady DJ 《Applied optics》2006,45(13):2955-2964
The analysis of a slitless volume holographic spectrometer is presented in detail. The spectrometer is based on a spherical beam volume hologram followed by a Fourier-transforming lens and a CCD. It is shown that the spectrometer is not sensitive to the incident angle of the input beam for the practical range of applications. A holographic spectrometer based on the conventional implementation is also analyzed, and the results are used to compare the performance of the proposed method with the conventional one. The experimental results are consistent with the theoretical study. It is also shown that the slitless volume holographic spectrometer lumps three elements (the entrance slit, the collimator, and the diffractive element) of the conventional spectrometer into one spherical beam volume hologram. Based on the unique features of the slitless volume holographic spectrometer, we believe it is a good candidate for portable spectroscopy for environmental and biological applications.  相似文献   
97.
In this paper, a stand-alone photovoltaic (SAPV) power supply system for Microner sprayer is identified and proposed. The designed system was composed of three main parts: sprayer, solar power supply and control system. Initially, the control board and data acquisition system were designed and simulated by the Proteus software and then implemented using an AVR microcontroller and tested via LabVIEW in the laboratory. Next, a prototype system was fabricated for evaluation purposes. A PV panel size of 88.5?cm2, positioned horizontally above operator's head that generates 26.4?Wh/day was used as a solar energy source. A small 2?Ah (12?V) battery is installed in the system as a stabiliser. This sprayer can work seven to nine hours daily. It is calculated that the average loss of collected energy due to non-application of maximum power point tracker was approximately 25%.  相似文献   
98.
The objective of this paper is to apply the activity-based costing (ABC) approach together with traditional costing (TC) for parts costing in flexible manufacturing systems (FMS) with the A(2) level of automation. We propose a new model for the implementation of ABC using the product cost tree concept. First, the required resources and activities for each part are recorded, and then their costs are calculated using the appropriate cost formulae. This model was applied in a forging industry. A comparison and analysis between ABC and TC was then carried out based on the computational results obtained from the case study. The results indicate that the ABC outputs are more reliable than the TC outputs, and thus the ABC approach is a more acceptable tool for parts costing in FMS.  相似文献   
99.
Lotsizing in capacitated pure flow shop with sequence-dependent setups has been considered in this paper. An exact formulation of the problem is provided as a mixed-integer program. It is well known that the capacitated lotsizing and scheduling problem (CLSP) is NP-hard. The introduction of serially arranged machines and sequence-dependent setups makes the problem even more complicated. Five MIP-based heuristics based on iterative procedures are provided. The first three heuristics are based on the original model but to solve non-small instances of problem, the last two heuristics are based on permutation flow shop problem which ignores the majority of combinations. To test the accuracy of heuristics, two lower bounds are developed and compared against the optimal solution. The trade-offs between solution quality and computational times of heuristics are also provided.  相似文献   
100.
In this article, we investigate the buckling analysis of plates that are made of functionally graded materials (FGMs) resting on two-parameter Pasternak's foundations under thermal loads. Three different thermal loads were considered, i.e., uniform temperature rise (UTR), linear and non-linear temperature distributions (LTD and NTD) through the thickness. The mechanical and thermal properties of functionally graded material (FGM) vary continuously along the plate thickness according to a simple power law distribution. Employing an analytical approach, the five coupled governing stability equations, which are derived based on first-order shear deformation plate theory, are converted into two uncoupled partial differential equations (PDEs). Considering the Levy-type solution, these two PDEs are reduced to two ordinary differential equations (ODEs) with variable coefficients. Then, the ODEs are solved using an exact analytical solution, which is called the power series Frobenius method. The appropriate convergence study and comparison with previously published related articles was employed to verify the accuracy of the proposed method. After such verifications, the effects of parameters such as the plate aspect ratio, side-to-thickness ratio, gradient index, and elastic foundation stiffnesses on the critical buckling temperature difference are illustrated and explained. The critical buckling temperatures of functionally graded rectangular plates with six various boundary conditions are reported for the first time and can serve as benchmark results for researchers to validate their numerical and analytical methods in the future.  相似文献   
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