Results 271 to 280 of about 109,469 (312)

Fractal-fractional Brusselator chemical reaction

Chaos, Solitons & Fractals, 2021
Abstract In this paper, we replace the classical differential operators with the fractal-fractional differential operators corresponding to the power law, exponential decay, and the generalized Mittag-Leffler kernels. These operators have two parameters created: the first is a fractal dimension and the second is a fractional order.
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Relationships in component-fractional and chemical composition of crude oils

Chemistry and Technology of Fuels and Oils, 1987
Certain generalizations and calculation techniques were examined for determining the distribution of fractions and chemical compositions of crude oils within the limits of the standard boiling points. Distribution parameters were calculated on the basis of volume.
A. S. �igenson, D. M. Sheikh-Ali
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Chemical fractionation in the solar system

Journal of Radioanalytical Chemistry, 1977
The cosmochemical and geochemical history of planetary material is reflected in relative and absolute abundances of two groups of trace elements; siderophiles and volatiles. Many of these elements can be determined at the requires levels only by radiochemical neutron activation analysis.
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Optimal control in chemical fractionation problem

Russian Mathematics, 2012
We study a chemical fractionation process in a tower. This process is described by a system of first-order partial differential equations. We obtain necessary optimality conditions for the optimal control problem in a class of smooth boundary controls with pointwise restrictions and perform numerical tests.
A. V. Arguchintsev, V. P. Poplevko
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Chemical fractionations in meteorites—X. Ureilites

Geochimica et Cosmochimica Acta, 1976
An investigation involving the measurement of 17 trace elements in 4 ureilites was conducted with the objective to obtain information for the characterization of the two components of the ureilites. The groundmass of the mineral is an olivine-clinopyroxene rock which is presumably the residue left after partial melting of a more primitive precursor ...
Hideo Higuchi, John W Morgan, R Ganapathy, Edward Anders   +3 more
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FRACTIONATION OF GERMANIUM ISOTOPES IN CHEMICAL REACTIONS

Canadian Journal of Chemistry, 1964
Isotopic vibrational frequencies and the corresponding partition-function ratios for several compounds containing Ge70 and Ge76 have been calculated at various temperatures. The theoretical equilibrium constants for germanium isotope-exchange reactions derived from these partition-function ratios indicate that noticeable germanium isotope ...
H. M. Brown, H. R. Krouse
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Chemical Fractionation of Antiviral Plants

Medicina et Pharmacologia Experimentalis, 2008
S C, Chou, S, Ramanathan, W, Cutting
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Chemical composition and fractionation of the continental crust

Geologische Rundschau, 1991
A new estimate of the bulk continental crust is reported consisting of 57 percent lower crust (60% felsic and 40% mafic granulites) and 43 percent upper crust. The proportions of crustal units are based on petrological observations (Bohlen &Mezger, 1989).
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[Chemical fractionation of Brucella melitensis and the immunizing properties of a new fraction].

Developments in biological standardization, 1976
A complex phenol-insoluble fraction (fraction P.I.) extracted from Brucella melitensis presents immunizing properties already described by the authors. This fraction contains peptidoglycane whose immuno-adjuvant properties are known in numerous bacterial species.
J, Roux, A, Serre, S, Bascoul, C, Lacave, A, Lopez   +4 more
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THE CHEMICAL FRACTIONATION OF RAT BRAIN PROTEINS*

Journal of Neurochemistry, 1959
W, DINGMAN, M B, SPORN, R K, DAVIES
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