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991.
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Ivan Maksymov Josep Ferré-Borrull Josep Pallarès Lluis F. Marsal 《Photonics and Nanostructures》2012,10(4):459-462
The existence of photonic stop bands in the self-assembled arrangement of pores in porous anodic alumina structures is investigated by means of rigorous 2D finite-difference time-domain calculations. Self-assembled porous anodic alumina shows a random distribution of domains, each of them with a very definite triangular pattern, constituting a quasi-random structure. The observed stop bands are similar to those of photonic quasicrystals or random structures. As the pores of nanoporous anodic alumina can be infiltrated with noble metals, nonlinear or active media, it makes this material very attractive and cost-effective for applications including inhibition of spontaneous emission, random lasing, LEDs and biosensors. 相似文献
994.
995.
Biomass gasification for synthesis gas production represents a promising source of energy based on plasma treatment of renewable fuel resources. Gasification/pyrolysis of crushed wood as a model substance of biomass has been experimentally carried out in the plasma-chemical reactor equipped with gas–water stabilized torch which offer advantage of low plasma mass-flow, high enthalpy and temperature making it possible to attain an optimal conversion ratio with respect to synthesis gas production in comparison with other types of plasma torches. To investigate this process of gasification in detail with possible impact on performance, a numerical model has been created using ANSYS FLUENT program package. The aim of the work presented is to create a parametric study of biomass gasification based on various diameters of wooden particles. Results for molar fractions of CO for three different particles diameters obtained by the modeling (0.55, 0.52 and 0.48) at the exit are relatively good approximation to the corresponding experimental value (0.60). The numerical results reveal that the efficiency of gasification and syngas production slightly decreases with increasing diameter of the particles. Computed temperature inhomogeneities in the volume of the reactor are strongest for the largest particle diameter and decrease with decreasing size of the particles. 相似文献
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997.
Igor I. Ponomarev Ivan I. Ponomarev Yulia A. Volkova Marina Yu. Zharinova Dmitrii Yu. Razorenov 《Mendeleev Communications》2012,22(3):162-163
A new thermally stable polybenzimidazole film has been synthesized by nucleophilic aromatic substitution, transformed into a complex with phosphoric acid and tested as a proton-conductive membrane. 相似文献
998.
Daniel Ivan 《Numerical Functional Analysis & Optimization》2013,34(6):792-798
In this article, we apply methods of proof mining to obtain a uniform effective rate of asymptotic regularity for the Mann iteration associated to κ-strict pseudo-contractions on convex subsets of Hilbert spaces. 相似文献
999.
I. P. Dobrovol’skaya N. S. Tsarev O. M. Osmolovskaya I. A. Kasatkin E. M. Ivan’kova E. N. Popova G. A. Pankova V. E. Yudin 《Russian Journal of Applied Chemistry》2018,91(3):368-374
X-ray diffraction analysis and transmission electron microscopy were used to demonstrate that hydroxyapatite produced by the precipitation method is a powder composed of anisometric particles with longitudinal size of 70–100 nm and transverse size of 7–9 nm. The particles are constituted by crystallites with longitudinal sizes of 22–24 nm and transverse sizes of 8–10 nm. At a temperature of 600°C, the crystallite sizes grow, and the volume porosity and specific surface area decrease. Synthetic hydroxyapatite has a low thermal stability as compared with hydroxyapatite of biological origin. 相似文献