Intensification of transfer processes in a nonuniform gas-mixture stream

Starting from Boltzmann�like equations, moment equations for a general gas mixture are developed. The equations are closed, and the collision integrals evaluated, by using Grad's 13�moment approximations for the velocity distribution functions. The collision integrals are determined for all possible types of binary encounters, which include recombination and attachment, spontaneous fission and natural decay, charge exchange and elastic collisions, and excitation and fission� and fusion�like processes. The derivation of transport relationships is considered, while the extension of the results to include such direct radiative phenomena as absorption, photoionization, stimulated emission, and Compton scattering is also briefly discussed.

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GAS-PHASE SYNTHESIS OF DIAMOND STRUCTURES

NONEQUILIBRIUM PROCESSES. Vol. 2. Fundamentals of combustion ◽

10.30826/nepcap2018-2-01 ◽

2020 ◽

Author(s):

A. K. Rebrov ◽

Keyword(s):

Gas Phase ◽

Building Material ◽

Microwave Plasma ◽

Diamond Surface ◽

Gas Mixture ◽

Diamond Synthesis ◽

Phase Synthesis ◽

Transfer Processes ◽

Carbon Structures ◽

Complex Influence

The diamond synthesis from vapor (gas) phase is realized under complex influence of nonequilibrium transfer processes in activated gas mixtures by formation of carbon structures on a nascent diamond surface. The microwave plasma generates an active gas mixture and fragments of building material are transported

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Modeling Pneumatic Conveyor Duct Wear: A New Approach

Volume 1: Symposia, Parts A and B ◽

10.1115/fedsm2005-77014 ◽

2005 ◽

Author(s):

Prem Chand ◽

A. C. Saha ◽

Prafull Chand

Keyword(s):

Heat Transfer ◽

Mass Transfer ◽

Material Flow ◽

Gas Flow ◽

Gas Mixture ◽

New Approach ◽

Flow Phenomenon ◽

Transfer Processes ◽

Flow Through ◽

Difficult Situations

It was shown in one of our recent works [1] that, the apparently disconnected items like solid-gas flow phenomenon, duct wear and particle degradation are in fact beautifully connected involving all the three components of transfer processes — heat transfer, mass transfer and momentum transfer. This paper which basically is an extension of our work on Fluid Energy Mill [2] aims at predicting duct wear while transporting solids-gas mixture in pneumatic conveyor even in most difficult situations like flow through bends under interference situation. The paper elaborates the methodology used for wear prediction and highlights the effect of several parameters like material flow rate etc. on the nature and extent of the duct wear.

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Electric resistence hysteresis of platinum filament in chilled air/hydrogen mixtures

Фізика і хімія твердого тіла ◽

10.15330/pcss.21.3.420-425 ◽

2020 ◽

Vol 21 (3) ◽

pp. 420-425

Author(s):

V. V. Каlіnchak ◽

O. S. Chernenko ◽

A. V. Fedorenko

Keyword(s):

Catalytic Combustion ◽

Solid Surfaces ◽

Industrial Processes ◽

Gas Mixture ◽

Transfer Processes ◽

Complex Process ◽

Catalytically Active ◽

Oxidation Of Hydrogen ◽

Hydrogen Mixtures ◽

Combustible Mixtures

Ignition of gaseous combustible mixtures on catalytically active hot solid surfaces has numerous applications in many industrial processes and is a complex process that involves close interaction between surface processes and transfer processes in the gas mixture. In this paper, stable and critical states catalytic oxidation of hydrogen impurities in air on a platinum filament are considered. It is shown that filament temperature and its resistance depending on the mixture temperature and hydrogen concentration are of the hysteresis features. Within this hysteresis region, it is possible to achieve the catalytic combustion mode of hydrogen as a result preheating the catalyst filament above a certain critical value. The dependence of the limiting hydrogen's concentration on catalyst filament's diameter, above which is observed in the cold gas mixture self-sustaining catalytic combustion without electric current.

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Effect of Niacin on Mitochondria of Allium Cepa Root Cells

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100060404 ◽

1967 ◽

Vol 25 ◽

pp. 78-79

Author(s):

M. Arif Hayat

Keyword(s):

Nicotinamide Adenine Dinucleotide ◽

Hydrogen Transfer ◽

Nicotinamide Adenine Dinucleotide Phosphate ◽

Nicotinamide Adenine ◽

Root Tips ◽

Root Cells ◽

Transfer Processes ◽

Standard Procedures ◽

A Cell ◽

Critical Interest

Although it is recognized that niacin (pyridine-3-carboxylic acid), incorporated as the amide in nicotinamide adenine dinucleotide (NAD) or in nicotinamide adenine dinucleotide phosphate (NADP), is a cofactor in hydrogen transfer in numerous enzyme reactions in all organisms studied, virtually no information is available on the effect of this vitamin on a cell at the submicroscopic level. Since mitochondria act as sites for many hydrogen transfer processes, the possible response of mitochondria to niacin treatment is, therefore, of critical interest.Onion bulbs were placed on vials filled with double distilled water in the dark at 25°C. After two days the bulbs and newly developed root system were transferred to vials containing 0.1% niacin. Root tips were collected at ¼, ½, 1, 2, 4, and 8 hr. intervals after treatment. The tissues were fixed in glutaraldehyde-OsO4 as well as in 2% KMnO4 according to standard procedures. In both cases, the tissues were dehydrated in an acetone series and embedded in Reynolds' lead citrate for 3-10 minutes.

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