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91.
Aggregation‐induced emission (AIE) is commonly observed in irregular bulk form. Herein, unique aggregation properties of an AIE‐active complex into branched supramolecular wires are reported for the first time. Mono‐cyclometalated Ir(III) complex shows in‐plane J‐aggregation at the air–water interface owing to the restriction of intramolecular vibration of bidentate phenylpyridinato and intramolecular rotations of monodentate triphenylphosphine ligands at air–water interface. As a consequence, a large enhancement of luminescence comparable to the solid state is obtained from the monolayers of supramolecular wires. This unique feature is utilized for the fabrication of light‐emitting diodes with low threshold voltage using supramolecular wires as active layer. This study opens up the need of ordered assembly of AIE complexes to achieve optimal luminescence characteristics.  相似文献   
92.
Multimedia Tools and Applications - This paper presents an algorithm for removal of ‘salt and pepper’ noise from color images. Adaptive fuzzy filter based on histogram estimation (AFHE)...  相似文献   
93.
In the present study, we used five different polymorphic markers to construct the haplotype at the adenomatous polyposis coli (APC) locus in families with familial adenomatous polyposis (FAP) and in the normal Italian population. Non-ambiguous haplotypes were reconstructed from 246 normal chromosomes and 65 FAP chromosomes. In the control population, the four polymorphisms intragenic to APC gave rise to 16 haplotypes, the most common of which (II and XV) accounted for over 50% of all chromosomes. In FAP patients, 13 haplotypes were found but their distribution was not statistically different from normal subjects. Eighty complete chromosomal haplotypes (many fewer than the theoretical maximum of 208) for the five polymorphic sites assayed were observed in the control population, 35 being found in the FAP patients. We compared the distribution of these haplotypes within the two groups; no statistically significant differences between normal and FAP chromosomes were found. The elevated heterogeneity of FAP chromosomes was clearly confirmed by the observation that 19 patients who carried one or other of the two most common APC mutations (nt 3183 and nt 3927) showed 18 different haplotypes. On the basis of these results, we were not able to identify a founder FAP chromosome. Various mechanisms are presented to explain this observation.  相似文献   
94.
95.
A broadband circularly polarized rectangular loop antenna is developed. The broadband performance is achieved by adding a pair of parasitic loops inside the rectangular loop. Good impedance matching is obtained by introducing a broadband balun. The proposed rectangular loop has a bandwidth of 46% for axial ratio/spl les/2dB and 50% for VSWR/spl les/2 with a gain of around 8dBi.  相似文献   
96.
We propose a low-loss slotline (SL) stepped circular ring termination for use in a microstrip-to-slotline (MS-to-SL) transition. Not only does this termination achieve broadband characteristics, but it also reduces SL radiation. The experimental results show that, using the proposed technique, the radiation loss around the pass-band frequency is lower than that of the conventional transitions using radial or circular pad terminations  相似文献   
97.
A new technique for design centering and yield enhancement of devices and circuits is presented. The proposed method uses neural networks for device and/or circuit modeling and genetic algorithms for parametric yield optimization. It uses a Monte Carlo-based method for yield estimation via the neural models (thus consuming less time) and genetic algorithms for efficient design centering. The neurogenetic methodology has been used for design centering of SiGe heterojunction transistors and millimeter-wave voltage controlled oscillators. It results in significant yield enhancement of the SiGe heterojunction bipolar transistors (from 25% to 75%) and voltage controlled oscillators (from 8 % to 85 %). To the best of our knowledge, this method has not been reported previously.  相似文献   
98.
Derivation of mathematical relationship between torque and speed during shearing in concrete rheometer with vane geometry has been presented in this paper. Resistance offered by concrete below and above the vane as well as effect of concrete resistance from the annulus were taken into consideration to represent actual flow condition of concrete during shearing. An expression for total shear stress has been derived from where shear stress versus torque and shear strain rate versus rotational frequency relationships have been established for the vane geometry of a concrete rheometer.  相似文献   
99.
Short Path Distillates of vacuum residue (boiling above 545 °C) is taken as feedstock for this study. Wax from this fraction is separated by solvent extraction method using methyl iso-butyl ketone (MIBK) as solvent. Both wax and the feedstock are characterised with the help of ASTM and IP procedures. Separated wax is fractionated at different temperatures, say 0–30 °C using MIBK as solvent. High temperature gas chromatography (HTGC) technique is used to study the distribution of alkane carbon number in all the fractions. It is observed that the wax contains very high molecular weight hydrocarbons as high as C67H136. HTGC technique as well as the Differential Scanning Calorimetry (DSC) indicates that all the fractions of the wax contain two types of hydrocarbons, one having high molecular weight alkanes (> 600) and another having low mol. wt. alkanes (~ 400). Thermal analysis by DSC technique further indicates that the wax is microcrystalline in nature having a low degree of crystallinity, 17%, as evidenced by XRD studies. Both high and low molecular weight waxes can also be separated based on their solubility characteristics.  相似文献   
100.
We report high peak-to-valley current ratio (PVR) resonant tunneling diodes (RTDs) bonded to silicon. Pseudomorphic AlAs/In0.53Ga0.47As/InAs resonant tunneling diode structures grown on semi-insulating InP with peak-to-valley current ratios as high as 30 at 300 K have been separated from the growth substrate and bonded to silicon substrates coated with Si3N 4, forming thin film devices. In addition, thin film multiple stack RTD structures have been bonded to silicon substrates. The I-V characteristics of both the single and multi-stacked thin film RTD's exhibit no signs of degradation after bonding to the host substrate. These results are the first successful demonstration of InP based electronics bonded to a silicon host substrate and enable the integration of RTDs with conventional silicon circuitry  相似文献   
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