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31.
Drying of sintered spheres of coarse glass beads with a wide sintering range in superheated steam under vacuum was studied.

In samples with sintered angles of 7.5° -27°, the experimental normalized drying rates in superheated steam at pressures of 7.3-7.9mmHg were smaller than those for 56.0-767.6 mmHg in the vicinity of the critical moisture cotents for 56.0-767.6GmmHg. As reported in an earlier paper, there were  相似文献   
32.
In 1890, a twelve-story octagonal sight-seeing tower was constructed as a high rise building in Tokyo Asakusa Park. In 1923, however, the top of the tower from the eighth floor up collapsed due to the Great Kanto Earthquake. In order to raise public interest in disaster prevention, we performed as a virtual experiment a conceptual attempt to save the tower without fundamentally changing its architectural characteristics by applying the most advanced structural control techniques. In the simulation, the top of the tower from the eighth floor experienced, almost exactly as described in historical record, a shear fracture during the initial period of principal shock. The modified Ryounkaku Tower would have ensured a comfortable margin of safety even against earthquakes more severe than the Great Kanto Earthquake in 1923.  相似文献   
33.
Abstract— Large‐screen (32‐in. WXGA and 17‐in. VGA) displays using metal—insulator—metal (MIM) cathode arrays have been developed. A cathode structure with low‐resistance electrodes and low‐capacitance emitters shortens signal delay and decreases the voltage drop in large MIM‐cathode arrays. By using a dual‐scan method, the signal delay was suppressed to less than 30% of the horizontal scan time in the 32‐in. WXGA panel. Emission efficiency of the cathode array was improved to 3% by reducing the surface work function of the top electrode from 4.7 to 3.9 eV. The cathode life was also improved to more than 10,000 hours. The display panel incorporating the cathode arrays and high‐efficiency P22‐phosphor screens with 3‐mm spacers showed high screen brightness (average brightness, 378 cd/m2; peak brightness, 832 cd/m2) at an anode voltage of 10 kV.  相似文献   
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35.
A partial-contact stress corrosion crack (SCC) is electrically modeled as a crack region with non-zero conductivity in eddy current testing (ECT). This partial-contact effect is excluded by an optimally designed crack-conductivity-insensitive depth characterization signal function (DCSF), and consequently the master curves obtained from electric-discharge machining (EDM) notches can be utilized directly in the depth sizing of SCCs. Furthermore, a crack conductivity independent artificial neural network (ANN) is constructed so that the entire depth profile can be reconstructed regardless of the crack conductivity. These two approaches are numerically validated and applied to the characterization of SCCs in SUS304 from measurement ECT signals. The average depth of each SCC is fast estimated from the DCSF, and the detailed depth profile is reconstructed from ANN. The ECT depth-sizing results show reasonable agreement with UT-TOFD measurement.  相似文献   
36.
介绍一种工业用2.5 kA/1.2 kV两单元IGBT模块.在该大电流器件中,P端到N端的内部连线电感非常小.半导体硅片的巧妙布局有效地提高了模块的散热能力,采用铝底板直接连接绝缘基板来提高热循环能力.对于这种底板面积较大的器件,为了获得更好的底板和散热片之间的热接触.底板被分成几段.2.5 kA/1.2 kV两单元IGBT模块的封装同样适用于1.8 kA/1.7 V两单元IGBT模块.  相似文献   
37.
Effect of glycerol in catalyst ink on the micro/nano structures of polymer electrolyte membrane fuel cells (PEMFCs) catalyst layers was investigated. Catalyst layers were fabricated by the decal method for various mass ratios of glycerol to carbon in the catalyst ink rgc (=mg/mc) from 0 to 20, and thus change the micro/nano structures of catalyst layer. The structures were evaluated by measuring the pore size with a mercury porosimeter and by observing the surface with a field emission scanning electron microscope (FE-SEM). At rgc < 5, although the residual glycerol was almost zero, the cell performance decreased with decreasing rgc, suggesting that the structure of the catalyst layers significantly depended on rgc. At rgc > 5, the remaining glycerol was proportional to rgc. Because remaining glycerol blocks the pores and reduces the reaction sites, the cell performance decreased with increasing rgc. If the remaining glycerol is removed by steam water, the performance is improved to the same level of the maximum performance for not steamed MEAs.  相似文献   
38.
A magenta subsidiary colour was isolated from commercial Food Blue No. 1 (B-1; Brilliant Blue FCF). The absorption maximum for this subsidiary colour at 580nm is outside of the range of 614-628nm found for other subsidiary colours and m,m -B-1. On the basis of MS and NMR analyses, the structure of the subsidiary colour was elucidated as the disodium salt of 2-[[4-[Nethyl-N-(3-sulphophenylmethyl)amino]phenyl][4-oxo2,5-cyclohexadienylide acid. HPL C analyses revealed that 24 batches of commercial Food Blue No. 1 (three manufacturers) contain 0.1- 0.8% (average: 0.5% ) of the magenta subsidiary colour.  相似文献   
39.
Methyl methacrylate (MMA) was polymerized by thiophenol without oxidants. Hydroquinone had no effect on the polymerization, indicating that the polymerization proceeded via a non-radical process. Since other monomers with an x,β-unsaturated carbonyl group polymerized similarly, the initiation and propagation were explained by the Michael addition. Radical scavengers such as 1,1-diphenyl-2-picrylhydrazyl(DPPH) and galvinoxyl enhanced the polymerization because of an accompanying radical polymerization initiated by radical species formed by the reaction of them with thiophenol. Aluminium acetylacetonate, which has no effect on radical polymerization, accelerated the thiophenol-initiated polymerization supporting the postulated mechanism.  相似文献   
40.
We have shown previously that random dots with an interocular time delay (ITD), the time difference of the onset of dots between the two eyes, yield both apparent depth and motion, although depth and velocity are covariant and, thus, ITD is inherently ambiguous. The depth of random dots with ITD was proportional to ITD, suggesting that the visual system assumes a constant velocity of the dots and determines depth on the basis of this constant velocity. We performed psychophysical experiments to investigate whether subjects perceive a constant velocity with a variety of ITDs in random dots aligned along a single vertical line that ensures neither apparent motion nor accidental disparity between the dots. The results showed that subjects perceive a constant velocity for a variety of ITDs with simultaneous perception of depth in proportion to ITD, indicating the priority of depth over velocity in ambiguous binocular perception derived from ITD.  相似文献   
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