Steam Plasma Treatment of Organic Substances for Hydrogen and Syngas Production

Gasification of several organic materials in steam plasma generated in a special plasma torch with a water-stabilized arc was investigated. Thermal plasma with very high enthalpy and low mass flow rate is produced in an arc discharge which is in direct contact with water. Biomass and several types of solid and liquid organic waste were gasified by plasma aided reactions of materials with water, carbon dioxide and oxygen. Composition of produced gas, energy balance of gasification process and gasification efficiency were determined from measured data. Synthesis gas with high content of hydrogen and carbon monoxide and very low content of carbon dioxide, light hydrocarbons and tar was obtained for all tested materials. Comparison of measured data with results of theoretical computations confirmed that steam plasma gasification produces syngas with composition which is close to the one obtained from thermodynamic equilibrium calculations.     

Photostability and fluorescence parameters of porphyrinoids: The effect of the macrocycle structure and the medium

The effects of the macrocycle structure and the medium nature on photodecomposition of porphyrinoids under UV irradiation have been studied. The influence of protonation, nonplanar structure of the molecule, and reactivity of NH bonds on the photostability of porphyrins and their analogs has been shown.     

Sedimentation of a cloud of a bidispersed aerosol onto a flat horizontal surface

Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, No. 2, pp. 101–108, March–April, 1992.     

Two-Dimensional Excitons in Multiple GaN/AlN Monolayer Quantum Wells

JETP Letters - The decay kinetics of low-temperature exciton photoluminescence in a heterostructure with multiple GaN/AlN monolayer quantum wells, which is prepared by molecular beam epitaxy, is...     

Manifestation of oxygen desorption in photoluminescence spectra of ZnO

The influence of oxygen desorption on the photoluminescence of zinc oxide has been investigated. Photodesorption and thermal desorption of oxygen have been controlled using mass spectrometry. It has been found that the removal of oxygen from the ZnO surface leads to a manifold increase in the exciton photoluminescence intensity. The process has a reversible character. The mechanism of increase in the exciton luminescence intensity of ZnO during the oxygen desorption has been discussed.     

Effect of conditions of thermal treatment on the porous structure of an aluminum oxide-containing nanofibrous aerogel

The effect the conditions of thermal treatment have on a specific surface and the number of primary adsorption centers is studied. The relationship between changing adsorption characteristics and changes in the structure of nanofibrous aluminum oxide is considered.     

Investigation of a Contamination Film Formed by the Electron Beam Irradiation

Technical Physics - In the study of materials on electron probe devices in the field of action of the electron beam, a contaminating hydrocarbon film is formed, which affects the experimental...     

Combined hydrogenation of carbon oxides on catalysts bearing iron and nickel nanoparticles

The reaction of the hydrogenation of a mixture of carbon oxides on ultradisperse powder (UDP) catalysts containing Fe and Ni nanoparticles and their bimetallic mechanical mixtures was investigated. It was established that the main reaction product on UDP Ni is methane, while the main products on the bimetallic systems are methane and ethylene. A synergetic effect was observed on the bimetallic catalyst under investigation. It was revealed that the hydrogenation of a mixture of carbon oxides proceeds through the stage of dissociative adsorption of both components, CO and CO₂. The olefin selectivity of the process was explained by the participation of different forms of adsorbed hydrogen (H_I: H_II) at the catalyst surface. It is assumed that the hydrogenation of carbon oxides on iron-nickel catalysts proceeds either through the jumpover effect or via hydrogen spillover.