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121.
Three dimensional (3D) microarrays utilizing hydrogel matrixes are becoming increasingly attractive as a desired format for bio-analysis. These materials offer significant advantages as a scaffolding for capture agents over more conventional two dimensional (2D) printed formats in both captures per site and the ability to provide an environment more closely resembling that of a free solution. Biocept has developed a flexible three dimensional polyethylene glycol (PEG) polymer based platform suitable for a variety of biological assays. This novel approach is simple, biocompatible and provides a high degree of reproducibility and very low variability in the final array.  相似文献   
122.
Oxygen high pressure (up to 16 MPa) has been introduced in the oxygen-annealing step necessary to make the YBa2Cu3Ox phase superconducting (change x from 6 to about 7). It enables a displacement in the equilibrium phase diagram towards higher temperatures, which means the possibility to achieve the same final oxygen content as the one at low temperature, but with the benefit of higher diffusion rates. Initial development made on thin bars (1.5–3 mm thick) has confirmed the interest of using a high pressure of oxygen. TEM observations have shown an increase of twin density associated with higher Jc. This is in agreement with other works claiming the possibility of higher Jc by twin engineering, and more precisely by twin refinement while annealing at high temperature. We report the successful application of this process without any adjustment to so-called thin-wall single-domain samples. These samples are obtained by growing a crystal on a pellet already shaped with an array of holes. The advantage is that, as far as diffusion processes are concerned, the typical length is not anymore the diameter of the sample, but the thickness of the walls between holes. The trapped field of 16 mm diameter Y123 thin-wall single-domain samples was doubled (0.6 T vs. 0.3 T at 77 K) in a rather short annealing time (about 3 days). Microstructures as well as magneto-optical observations of plain and thin-wall samples evidenced a reduction of cracks in the thin-wall samples. Improved performances were confirmed by further characterizations performed from 77 down to 20 K using the pulse-field facilities of the LNCMP at Toulouse.  相似文献   
123.
124.
In this paper we describe the efficient and substantial decomposition of C60 in toluene solution, induced by moderate intensity (I = 20 - 55 MW cm-2) near infrared (γ = 1064 nm) laser radiation. This behavior is surprising since both uncharged fullerene and toluene do not have any absorption bands at this wavelength. The decomposition efficiency and products are investigated with UV-Vis absorption spectrophotometry and high-performance liquid-chromatography (HPLC). Possible mechanisms of the fullerene decomposition are discussed.  相似文献   
125.
A possibility to develop the so called TASER (Terahertz-Amplification-by-the-Stimulated-Emission-of- Radiation) by using two-dimensional (2D) electron transport in quantum well (QW) structures is investigated by Monte Carlo simulation of the optical-phonon-emission assisted transit-time resonance (OPTTR) of 2D electrons in momentum space under the low lattice temperature. A considerable extension of the frequency region for THz radiation generation (upto 5 times) when going from 3D- to 2D-case is predicted.  相似文献   
126.
Classification based on Fisher's linear discriminant analysis (FLDA) is challenging when the number of variables largely exceeds the number of given samples. The original FLDA needs to be carefully modified and with high dimensionality implementation issues like reduction of storage costs are of crucial importance. Methods are reviewed for the high dimension/small sample size problem and the one closest, in some sense, to the classical regular approach is chosen. The implementation of this method with regard to computational and storage costs and numerical stability is improved. This is achieved through combining a variety of known and new implementation strategies. Experiments demonstrate the superiority, with respect to both overall costs and classification rates, of the resulting algorithm compared with other methods.  相似文献   
127.
Metathesis polytricyclononenes were synthesized via ROMP polymerization in the presence of the 1‐st generation Grubbs catalyst and their gas‐transport properties were studied for the first time. The aim of this work was to evaluate the influence of Me3E‐groups (E = C, Si, Ge) on gas permeation parameters of ROMP materials. New metathesis poly(3‐tert‐butyltricyclononene‐7) and poly(3‐trimethylgermyltricyclononene‐7) were obtained with high yields (up to 95%) and high‐molecular weights (Mw~3–7×105 g mol?1). The glass transition temperatures of the ROMP polytricyclononenes with Me3E‐groups decreased when E was changed from C to Si and then to Ge. It was shown that the polytricyclononene containing Me3Si‐groups has the highest gas permeability while the polytricyclononene containing Me3C‐substituents has the lowest gas permeability. In addition, the gas permeation parameters were estimated for ROMP Me3Si‐ and Me3Ge‐substituted polytricyclonona‐3,7‐dienes. So the influence of the second double bond in the monomer units on the permeability of the polymers obtained was studied. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41395.  相似文献   
128.
The development of motion capturing devices poses new challenges in the exploitation of human‐motion data for various application fields, such as computer animation, visual surveillance, sports, or physical medicine. Recently, a number of approaches dealing with motion data have been proposed, suggesting characteristic motion features to be extracted and compared on the basis of similarity. Unfortunately, almost each approach defines its own set of motion features and comparison methods; thus, it is hard to fairly decide which similarity model is the most suitable for a given kind of human‐motion retrieval application. To cope with this problem, we propose the human motion model evaluator, which is a generic framework for assessing candidate similarity models with respect to the purpose of the target application. The application purpose is specified by a user in form of a representative sample of categorized motion data. Respecting such categorization, the similarity models are assessed from the effectiveness and efficiency points of view using a set of space‐complexity, information‐retrieval, and performance measures. The usability of the framework is demonstrated by case studies of three practical examples of retrieval applications focusing on recognition of actions, detection of similar events, and identification of subjects. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
129.
Solvent‐free protocols for Miyaura borylation and the one‐pot, two‐step homocoupling of aryl halides are reported for the first time. Bis(dibenzylideneacetone)palladium(0) [Pd(dba)2] is an optimal source of palladium for Miyaura borylation, while for one‐pot two‐step homocoupling palladium(II) acetate [Pd(OAc)2] gives highest yields. Aryl bromides are coupled most efficiently using the DPEphos ligand. Chlorides are coupled using XPhos. The developed protocols are robust, versatile and easily reproducible on a large scale.

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130.
本例描述了一个简单的电缆测试仪,它能形象地显示出一根16线电缆束(用于超声辅助驻车系统)的通断问题。一家承包商小批量地生产该线束,因此不适合采用自动化测试仪。为简单起见,用测试信号驱动几只LED,形象化地表示出通断情况。图1中的电路产生一个从0至15的二进制数(0000至1111)。可  相似文献   
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