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51.
New efficient intermetallide catalysts for hydrogen storage in reversible processes of aromatics hydrogenation and naphthene dehydrogenation were studied. These catalysts provide an enhanced activity in the dehydrogenation of saturated organic molecules, with no side reactions like cracking, hydrogenolysis, ring opening, or coke formation occurring on these catalysts. The use of intermetallides provides some hydrogen storage capacity in the low-temperature region, while their catalytic activity in the dehydrogenation affords the hydrogen supply in the high-temperature range. 相似文献
52.
Specific features connected with using air heat pumps under the conditions of cold climate are considered. Ways for achieving more efficient operation of these pumps are shown. Results from technical-economic studies on analyzing the prospects of using air heat pumps for supplying heat to low-rise buildings in different regions of Russia in comparison with alternative solutions are presented. 相似文献
53.
Leonid G. Kazovsky Eli Turgeman 《International Journal of Circuit Theory and Applications》1982,10(3):231-242
A non-recursive adaptive impulse noise canceller (AINC) is investigated. The AINC is designed to suppress long impulsive interferences which are a primary source of errors in many communication systems. Performance of the AINC depends upon the input filter of the receiver. It is shown that the optimum input filter is LPF; the optimum LPF bandwidth exists which provides the minimum error rate of the receiver. The system error rate is studied by means of a computer simulation. Simulation results indicate that the AINC provides a very effective suppression of impulse noise. However, conditions in a real communication channel may be quite different from those chosen for simulation. Therefore, further research remains to be done before the AINC can be recommended for practical applications. 相似文献
54.
Wide‐band aperture array using a four‐channel manifold‐type planar multiplexer and digital 2‐D IIR filterbank 下载免费PDF全文
Arindam Sengupta Arjuna Madanayake Roberto Gómez‐García Leonid Belostotski 《International Journal of Circuit Theory and Applications》2016,44(12):2085-2100
Emerging wide‐band communications and spectrum‐sensing systems demand support for multiple electronically scanned beams while maintaining a frequency independent, constant far‐field beam width. Realizing existing phased‐array technology on a digital scale is computationally intensive. Moreover, digitizing wide‐band signals at Nyquist rate requires complex high‐speed analog‐to‐digital converters (ADCs), which is challenging for real developments driven by the current ADC technology. A low‐complexity alternative proposed in this paper is the use of radio‐frequency (RF) channelizers for spectrum division followed by sub‐sampling of the RF sub‐bands, which results in extensive reduction of the necessary ADC operative frequency. The RF‐channelized array signals are directionally filtered using 2‐D digital filterbanks. This mixed‐domain RF/digital aperture array allows sub‐sampling, without utilizing multi‐rate 2‐D systolic arrays, which are difficult to realize in practice. Simulated examples showing 14–19 dB of rejection of wide‐band interference and noise for a processed bandwidth of 1.6 GHz are demonstrated. The sampling rate is 400 MHz. The proposed VLSI hardware uses a single‐phase clock signal of 400 MHz. Prototype hardware realizations and measurement using 65‐nm Xilinx field‐programmable gate arrays, as well as Cadence RTL synthesis results including gate counts, area‐time complexity, and dynamic power consumption for a 45‐nm CMOS circuit operating at B DC = 1.1 V, are presented. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
55.
Alexander S. Goryashchenko Maria G. Khrenova Anna A. Bochkova Tatiana V. Ivashina Leonid M. Vinokurov Alexander P. Savitsky 《International journal of molecular sciences》2015,16(7):16642-16654
This article describes the genetically encoded caspase-3 FRET-sensor based on the terbium-binding peptide, cleavable linker with caspase-3 recognition site, and red fluorescent protein TagRFP. The engineered construction performs two induction-resonance energy transfer processes: from tryptophan of the terbium-binding peptide to Tb3+ and from sensitized Tb3+ to acceptor—the chromophore of TagRFP. Long-lived terbium-sensitized emission (microseconds), pulse excitation source, and time-resolved detection were utilized to eliminate directly excited TagRFP fluorescence and background cellular autofluorescence, which lasts a fraction of nanosecond, and thus to improve sensitivity of analyses. Furthermore the technique facilitates selective detection of fluorescence, induced by uncleaved acceptor emission. For the first time it was shown that fluorescence resonance energy transfer between sensitized terbium and TagRFP in the engineered construction can be studied via detection of microsecond TagRFP fluorescence intensities. The lifetime and distance distribution between donor and acceptor were calculated using molecular dynamics simulation. Using this data, quantum yield of terbium ions with binding peptide was estimated. 相似文献
56.
A failure mechanism of submarine landslides based on the phenomenon of shear band propagation has been investigated using the energy balance approach. Dynamic analysis includes inertia effects in the sliding layer and viscous resistance of the water, but ignores elastic and plastic wave propagation in the sliding layer. The resulting differential equation has been solved numerically. Analytical approximation of this numerical solution provides a convenient basis for the parametric and sensitivity studies. The solution allows assessing the velocity and acceleration of both the landslide and the shear band at the moment when the slide fails due to the limiting equilibrium (i.e., the initial post-failure velocity). The effects of the initial landslide velocity on the tsunami wave height are discussed and validated for a number of landslide examples. 相似文献
57.
Anastasia V. Ponasenko Maria V. Khutornaya Anton G. Kutikhin Natalia V. Rutkovskaya Anna V. Tsepokina Natalia V. Kondyukova Arseniy E. Yuzhalin Leonid S. Barbarash 《International journal of molecular sciences》2016,17(9)
Severe bioprosthetic mitral valve calcification is a significant problem in cardiovascular surgery. Unfortunately, clinical markers did not demonstrate efficacy in prediction of severe bioprosthetic mitral valve calcification. Here, we examined whether a genomics-based approach is efficient in predicting the risk of severe bioprosthetic mitral valve calcification. A total of 124 consecutive Russian patients who underwent mitral valve replacement surgery were recruited. We investigated the associations of the inherited variation in innate immunity, lipid metabolism and calcium metabolism genes with severe bioprosthetic mitral valve calcification. Genotyping was conducted utilizing the TaqMan assay. Eight gene polymorphisms were significantly associated with severe bioprosthetic mitral valve calcification and were therefore included into stepwise logistic regression which identified male gender, the T/T genotype of the rs3775073 polymorphism within the TLR6 gene, the C/T genotype of the rs2229238 polymorphism within the IL6R gene, and the A/A genotype of the rs10455872 polymorphism within the LPA gene as independent predictors of severe bioprosthetic mitral valve calcification. The developed genomics-based model had fair predictive value with area under the receiver operating characteristic (ROC) curve of 0.73. In conclusion, our genomics-based approach is efficient for the prediction of severe bioprosthetic mitral valve calcification. 相似文献
58.
Jewgenij Botaschanjan Manfred Broy Alexander Gruler Alexander Harhurin Steffen Knapp Leonid Kof Wolfgang Paul Maria Spichkova 《Formal Aspects of Computing》2008,20(6):637-662
Formal verification of software systems is a challenge that is particularly important in the area of safety-critical automotive systems. Here, approaches like direct code verification are far too complicated, unless the verification is restricted to small textbook examples. Furthermore, the verification of application logic is of limited use in industrial context, unless the underlying operating system and the hardware are verified, too. This paper introduces a generic model stack, allowing the verification of all system layers as well as the concrete application models being used in the upper layers. The presented models and proofs close the gap between the correctness proof for the lower layers of car electronics developed at the Saarland University and the verification procedure for distributed applications developed at the Technische Universität München. 相似文献
59.
V. P. Orlovskii S. P. Ionov T. V. Belyaevskaya S. M. Barinov 《Inorganic Materials》2002,38(2):182-184
Based on crystal-chemical and thermodynamic data, a model was proposed for the synergistic participation of the carbonate ion in hydroxyl–fluoride ion exchange in the Ca channels of apatites (bony and dental tissue). The synergistic effect of the carbonate ion develops upon partial isomorphic substitution [PO4] groups and consists in equalizing the bonding energies of F– and OH– in the Ca channel. 相似文献
60.