Results 261 to 270 of about 538,729 (318)

The study of soil chemistry through quasi-steady-state models: I. Mathematical definition of model

Geochimica et Cosmochimica Acta, 1989
Abstract A mathematical method for studying the composition and speciation of soil solutions is presented. The method is formulated in general algebraic terms, and is adaptable to soil-water systems of virtually any chemical composition. Chemical processes in three different time frames are considered: fast, reversible processes, described in terms ...
Gerhard Furrer, John C. Westall, Phillip Sollins   +2 more
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Chemistry and Transport of Potassium during the Non‐Steady State of Syenite Leaching

Soil Science Society of America Journal, 2017
Core Ideas A flow system for the release and extraction kinetics of ions from a rock fertilizer. The initial release of ions from syenite
Kejing Li, Christi A. Dawydiak
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Improved Quasi-Steady-State-Approximation Methods for Atmospheric Chemistry Integration

SIAM Journal on Scientific Computing, 1997
Comprehensive atmospheric chemistry models are computationally intensive since the governing equations are nonlinear, highly coupled, and stiff. One of the commonly used methods is the quasi-steady-state-approximation (QSSA) method proposed by \textit{E. Hesstvedt}, \textit{O.Hov} and \textit{I.
Laurent O. Jay, Adrian Sandu, Florian A. Potra, Gregory R. Carmichael   +3 more
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Steady state and time-resolved spectroscopic studies of the photochemistry of 1-arylsilacyclobutanes and the chemistry of 1-arylsilenes

Canadian Journal of Chemistry, 1999
Direct photolysis of 1-phenylsilacyclobutane and 1-phenyl-, 1-(2-phenylethynyl)-, and 1-(4'-biphenylyl)-1-methylsilacyclobutane in hexane solution leads to the formation of ethylene and the corresponding 1-arylsilenes, which have been trapped by photolysis in the presence of methanol.
William J. Leigh, Rabah Boukherroub, Christine J. Bradaric, Christine C Cserti, Jennifer Schmeisser   +4 more
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An efficient Chebyshev wavelet based analytical algorithm to steady state reaction–diffusion models arising in mathematical chemistry

Journal of Mathematical Chemistry, 2015
zbMATH Open Web Interface contents unavailable due to conflicting licenses.
M. Mahalakshmi, G. Hariharan
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Calculating critical loads of acid deposition with PROFILE ? A steady-state soil chemistry model

Water, Air, & Soil Pollution, 1992
A steady state soil chemistry model was used to calculate the critical load of acidity for forest soils and surface waters at Lake GArdsjon in S.W. Sweden. The critical load of all acid precursors (potential acidity) for the forest soil is 1.64 kmolc ha−1 yr−1, and 1.225 kmolc ha−1 yr−1 for surface waters.
Per Wärfvinge, Harald Sverdrup
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Free Radical Addition Polymerization Kinetics without Steady-State Approximations: A Numerical Analysis for the Polymer, Physical, or Advanced Organic Chemistry Course

Journal of Chemical Education, 2014
A numerical analysis of the free radical addition polymerization system is described that provides those teaching polymer, physical, or advanced organic chemistry courses the opportunity to introduce students to numerical methods in the context of a simple but mathematically stiff chemical kinetic system.
H. Darrell Iler, Amber Brown, Amanda Landis, Greg Schimke, George A. Peters   +4 more
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Integrated Production Chemistry Management Of The Schoonebeek Heavy Oil Redevelopment in the Netherlands: From Project to Start-Up and Steady State Production

SPE Heavy Oil Conference Canada, 2012
Abstract This paper describes the production chemistry management process undertaken during the design, commissioning and start-up phases of the Schoonebeek redevelopment. Challenging separation issues, saline water, together with a multitude of other process conditions, resulted in complex, but robust application portfolio.
Andrew G. Shepherd, Stuart McGregor, Ruud Trompert, Sen Ubbels, Bob van de Gender, Theo van Ommen, Sjoerd van der Knoop   +6 more
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Applications of non‐steady‐state kinetics in physical organic chemistry: guidelines for the resolution of the kinetics of complex reaction mechanisms

Journal of Physical Organic Chemistry, 2001
AbstractThe resolution of the kinetics of the reversible consecutive second‐order reaction mechanism involving the formation of a kinetically significant intermediate, which does not reach steady state before late in the first half‐life, followed by an irreversible product‐forming reaction is discussed. It is shown that an apparent second‐order rate
Vernon D. Parker, Yi×ing Zhao
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A coupled one‐dimensional radiative‐convective, chemistry‐transport model of the atmosphere: 1. Model structure and steady state perturbation calculations

Journal of Geophysical Research: Atmospheres, 1985
An atmosphere model composed of a narrow band radiative‐convective (RC) code coupled with a one‐dimensional chemistry and transport code is described. The RC model, formulated in log‐pressure coordinates, includes accurate solar absorption calculations for O3, O2, H2O, and CO2.
A. J. Owens, Charles H. Hales, D. L. Filkin, C. Miller, J. M. Steed, J. P. Jesson   +5 more
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