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81.
An algorithm for the spectrum of the rotational component of surface ground motion during earthquake is derived. To obtain the rotation the total motion is decomposed into the wave components. Then the rotational motion is obtained in terms of the horizontal and vertical components treated as non-stationary random processes. The evolutionary spectrum of the rotational acceleration is a function of respective translational spectra, their co-spectrum and respective wave parameters. The analysis shows a shift of the higher frequency components in the rotational spectrum. The rotation is a function of the time derivative of translational components. 相似文献
82.
Zbigniew J. Lata Peter B. Aronhime 《Analog Integrated Circuits and Signal Processing》1997,13(3):275-284
New procedures are presented that yield cascadable, opamp based current-mode biquads from voltage-mode biquads without the use of voltage-mode to current-mode transformations. The opamps in the resulting current-mode circuits can be replaced by current-mode devices, such as current conveyors, producing circuits that are fully current-mode. The procedures are applied to several multi-opamp voltage-mode circuits to achieve current-mode lowpass, highpass, bandpass, notch, and allpass filters. The procedures are also applied to a single opamp circuit. Experimental results are given. 相似文献
83.
A numerical model for the hopping conductivity in 3-D disordered systems is presented. The relation between variable-range hopping conductivity and temperature for the low-temperature range is found. The advantage of the proposed model is that the size of the system investigated is not limited by the computer memory. 相似文献
84.
We have studied thin films of Ti-Al for use as resistance elements. It was found that Ti-40 wt.% Al thin films with a resistivity of 10 ω/□ possess stable characteristics. We have also studied the structure of Ti-Al thin films. Analysis of electron and X-ray diffraction patterns showed that Ti-40 wt.% Al films contained a fine-grained disordered intermetallic face-centred cubic TiAl phase whereas bulk TiAl had a tetragonal CuAu-type structure. 相似文献
85.
86.
Nitrogen base fractions were prepared from a heavy coal-derived liquid via two commonly accepted laboratory procedures and partially characterized. Significant differences in the composition of the two fractions suggest strongly that extreme caution should be exercised in interpreting and comparing the results of base characterization studies in which different base isolation procedures are used. 相似文献
87.
Zbigniew Lewandoswki 《Water research》1982,16(1):19-22
The rate of a waste water dentification process depends amongst others upon the temperature and the kind of compound used as electron donor. The results of measurements of denitrification kinetics using methanol, acetone and acetic acid have been presented. 相似文献
88.
An ion beam milling system utilizing a Kaufman-type source to etch patterns in conductive, semiconductive and insulating materials was used to examine the surface morphology of resistive thick films, and to modify the surface topography of biomaterials. The ion beam sputter modification of the different materials presently used or under consideration for electronic and implant devices were studied. A Japan Electron Optics Laboratory, model JSM-35 scanning electron microscope was used to examine all the materials tested. 相似文献
89.
90.
Zbigniew Jedliński Andrej Stolarzewicz Pawel Szewczyk Ryszard Tymczyński 《Polymer Bulletin》1980,2(8):555-563
Summary Polymerization of p-chlorophenyl glycidyl ether initiated by potassium glycolates (ethylene, propylene and 2-methyl propylene glycolatea) in DMSO containing some 18-crown-6 ether or glycol was investigated. For the reaction system containing the propylene glycolate asymmetrically substituted with a methyl group, relatively high polymerization rates were obtained as compared with those found for the other systems studied, the resultant polymers also having higher molecular weights and comparatively low polydispersities. Aliphatic double bonds were found to be absent in the polymers synthesized, which would suggest that in the anionic polymerization process studied the growing chain is not transferred to the monomer.Dedicated to Prof. C.I. Simionescu on the occasion of the 60th anniversary of his birthday 相似文献