Wyniki wyszukiwania - BazTech

1

Surface effects on the wave propagation in composites with random dispersive parallel cylindrical nanofibers

Kong Z., Qiang F. W., Wei P. J., Tang Q.

Archives of Mechanics

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2015

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Vol. 67, nr 5

355--370

EN

The propagation of elastic waves in composites with randomly distributed parallel cylindrical nanofibers is studied. The non-classical boundary conditions on the surface of nanofibers are derived by using the surface elasticity theory. The scattering waves from an individual nanofiber are obtained by the plane-wave expansion method. These scattering waves from all nanofibers are summed up to obtain the multiple-scattering waves. The effective propagation constants (speed and attenuation) of coherent waves and the associated effective dynamical moduli of composites are evaluated numerically. Based on these numerical results, the influences of the surface effects on the effective dynamical properties of composites are discussed.

2

Application of nitrogen injection displacement for fire extinguishment

Tang Q., Qin R. X., Chen Q. H., Zhang G. S.

AGH Journal of Mining and Geoengineering

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2012

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Vol. 36, no. 3

345-351

EN

The article introduced the basic theory of nitrogen injection displacement for fire extinguish, which is presented by Professor Guoshu Zhang, applied this technology in coal mine, and then verified the results through numerical simulation, the production got from the technology's application. Presented some new views in specific implementation of nitrogen injection displacement for fire extinguish.

PL

W niniejszym artykule opisano zastosowanie podstawowej teorii wypełniania zrobów azotem podczas gaszenia pożarów endogenicznych zaprezentowanej przez profesora Guoshu Zhang, jej zastosowanie w kopalni oraz weryfikację wyników za pomocą symulacji numerycznej i uzyskane efekty w związku z zastosowaniem tej technologii. Zaprezentowano szczegółowe zasady oraz poglądy na temat wypełniania zrobów azotem do zwalczania pożarów.

3

Invariant allometric relationship between aboveand below-ground biomass along a moisture gradient in North-West China

Cheng D., Wang G., Tang Q., Li T., Zhong Q.

Polish Journal of Ecology

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2009

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Vol. 57, nr 4

669-675

EN

Biomass allocation pattern is an important plant characteristic which influences how plants respond to abiotic and biotic heterogeneity. Prior studies indicate that above-ground biomass scales nearly isometrically with respect to below-ground biomass regardless of environment or phyletic affinity. However, such rule has been mostly tested with data on trees and usually without drought stress. Given the importance of this predicted relationship, it should be evaluated for a wider range of species and environmental conditions. Variations of the above- and belowground biomass (M[A] and M[R], respectively) were determined from five sites in north-west China, which compose a natural moisture gradient (aridity index ranging from 0.95 to 1.98). Model Type II regression protocols were used to compare the numerical values of M[A] vs M[R] scaling exponents (i.e. slopes of log-log linear relationships). The resulting five scaling exponents were indistinguishable and had a similar, nearly isometric slope (i.e. M[A] [is proportional to] M[R] [is approximately equal to] 1.0). Significant variation was observed in the Y-intercepts of the five regression curves, because of the absolute differences in M[A] or M[R]. These results support prior allometric theory, which reveals an isometric relationship between above- and below-ground biomass, and may provide a suitable method to estimate the regional below-ground biomass based on the direct aboveground measurements.