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1.
2.
The article established the regularities of change of the physicomechanical characteristics and strength of glass textolites in single and repeated thermal loading. It shows that under multiple loading the intense loss of strength of the investigated materials is due to increased porosity on account of the large number of microcracks appearing in the structure. A correlation is obtained between the elastic and strength characteristics and porosity in dependence on the temperature of multiple heating which in the first approximation is described by a polynomial of second degree with respect to temperature, multiplied by the reciprocal of porosity.Translated from Problemy Prochnosti, No. 6, pp. 53–58, June, 1991. 相似文献
3.
Ér. V. Kal’yanov 《Technical Physics Letters》2007,33(6):451-453
A new simple model of a system with chaotic dynamics, based on the equations of bistable systems, is considered. The possibility of converting harmonic signals into chaotic oscillations, which represent intermittent irregular and switching quasi-regular motions, is demonstrated by numerical methods. The mechanism of chaotization is analyzed using the results of numerical calculations. 相似文献
4.
5.
S Benk? S Drabant G Grézal I Urm?s M Cs?rg? I Klebovich 《Canadian Metallurgical Quarterly》1997,47(8):913-916
A comparative pharmacokinetic study has been performed in 19 healthy male volunteers in a single-dose, randomized, two way cross-over design with two preparations of gemfibrozil (CAS 25812-30-0) capsules each of them containing 300 mg active ingredient. The test preparation was Innogem 300 mg capsule. The plasma concentration of gemfibrozil was determined by a validated HPLC-UV analytical method. The statistical comparison of individual pharmacokinetic parameters (AUC0-16, AUC0-oc Cmax, tmax) of the two capsule preparations was performed by three-way analysis of variance (ANOVA), Wilcoxon's, Westlake's, Schuirmann's and Hanck-Anderson's method as well as by the calculation of confidence intervals on the ratio of test/reference. The relative bioavailability of the test preparation with respect to the reference preparation in terms of the AUC0-oc was 104.06 +/- 21.61%. No statistically significant difference was found between the pharmacokinetic parameters, calculated from plasma concentration-time curves, indicating that the two preparations were bioequivalent. 相似文献
6.
R. Meyer Hilde Hardtdegen R. Carius D. Grützmacher M. Stollenwerk P. Balk A. Kux B. Meyer 《Journal of Electronic Materials》1992,21(3):293-298
This paper presents a study of the structural and optical properties of strained GaInAs/ InP multiple quantum well (MQW) structures
fabricated by LP-MOVPE. The composition of the Ga
x
In1−x
As films ranged fromx = 0.17 tox = 1.0 and was determined by sputtered neutral mass spectrometry (SNMS) on thick layers. The structures of the MQW samples
with well widths from 1.5 to 5 nm were investigated by high resolution x-ray diffraction (HR-XRD). Simulations of the diffraction
patterns showed that transition layers of approximately 2 monolayer (ML) thickness with high lattice mismatch exist at the
interfaces. Photoluminescence (PL) measurements indicate well widths of a multiple of a monolayer with local variations of
one monolayer. The PL peak energies vary smoothly with the Ga concentration. These results were confirmed by optical absorption
measurements. 相似文献
7.
The properties of glasses of the lithium-aluminoborosilicate system were investigated, namely, the density, spreadability, thermal expansion, and nature of crystallized phases at various temperatures. A crystal-optical analysis was conducted. The glasses were used to prepare abrasive compositions. Their strength properties were studied as a function of the composition of the glass binder and the regime of heat treatment.Translated from Steklo i Keramika, No. 3, pp. 27–30, March, 1996. 相似文献
8.
The fluctuations observed by recording the picosecond pulses of a mode-locked laser with a synchroscan streak camera are due to the laser jitter and to the variations of the zero crossing of the synchronization. By means of a simple model, it is shown that the dispersions measured when the synchronization is generated from the mode-locker oscillator reflect the instantaneous time phase fluctuations of this oscillator. From the study of the experimental recordings with methods of time series analysis it results that the phase noise of the electronic oscillator is consistent with an underlying low-dimensional strange attractor. 相似文献
9.
Éntin S. V. Anzheurov N. M. Krasovitskii Yu. V. Panova O. A. Shcheglova L. I. 《Refractories and Industrial Ceramics》2003,44(3):194-198
An experimental setup for studying filter-assisted dust collection is described. The role of various factors — hydraulic resistance, filtering velocity, dust concentration, pressure drop, efficiency of recovery — in the performance of filters intended for use in the production of refractory materials is considered. The dust removal method was tested under industrial conditions at the Semilukskii Refractory Plant and can be recommended for wider use in different branches of industry. 相似文献
10.
Olivier Klein Steve Donovan Martin Dressel George Grüner 《Journal of Infrared, Millimeter and Terahertz Waves》1993,14(12):2423-2457
This report reviews the analysis used to extract the complex conductivity of a compound from a microwave cavity perturbation measurement. We intend to present a generalized treatment valid for any spheroidally shaped sample of arbitrary conductivity which is placed at either the electric or magnetic field antinode of the cavity. To begin with, we establish the relationship between the measured parameters and the conductivity for a spherical sample. Next, we extend these results to the case of spheroids; and for the first time, we cover all different configurations that one can possibly use to study an arbitrary conducting sample inside a cavity: in particular, all possible orientations of the sample with respect to the applied field are solved. 相似文献