Results 301 to 310 of about 555,478 (356)

Nonsink Dissolution Rate Equation

Journal of Pharmaceutical Sciences, 1973
An equation was developed which describes the dissolution of monodisperse particles beyond the point where concentrations are small compared to solubility. If it is assumed that a stagnant layer model applies, the thickness of these layers is of the same order of magnitude as calculated via the Hixson-Crowell treatment but dissolution rate constants ...
P, Pothisiri, J T, Carstensen
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Dissolution Rate Equations in CoIumn-Confined Dissolution

Journal of Pharmaceutical Sciences, 1976
Equations are derived for the dissolution of a soluble solid in a column into a liquid stream. The equations are substantiated by experiments using oxalic acid dihydrate as a test substance. The dissolution rate constant, k, of oxalic acid dihydrate depends on linear velocity, v (centimeters per second), by the following equation: k = (2.54 +/- 0.76) X
J T, Carstensen, K, Dhupar
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Dissolution rates of silicate cements

Biomaterials, 1982
The literature relating to the dissolution of the silicate cements is reviewed, including the methodology, intrinsic factors relating to composition and method of mixing, curing etc. and extrinsic factors, i.e. the medium, pH, ionic strength etc. to which the sample of cement is exposed.
A T, Kuhn, G B, Winter, W K, Tan
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Dissolution Rates of Polyphase Mixtures

Journal of Pharmaceutical Sciences, 1965
The theory for the dissolution rate of polyphase mixtures has been investigated and applied to several situations. Physical models involving simultaneous diffusion and rapid equilibria have led to relationships that describe experimental data rather well for the benzoic acid–salicylic acid, the benzocaine–caffeine, and the benzoic acid–trisodium ...
W I, Higuchi, N A, Mir, S J, Desai
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Dissolution Rates under Sink Conditions

Journal of Pharmaceutical Sciences, 1971
Abstract Equations are given for the dissolution of a drug into an aqueous phase overlayered with a lipid phase, in which back transfer from the lipid phase is assumed possible. Consideration of both the presence and absence of back transfer, assuming in each that the amount of drug in the aqueous phase either approaches saturation or remains ...
P J, Niebergall, E T, Sugita, R L, Schnaare   +2 more
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Chalcopyrite dissolution rate laws

Applied Geochemistry, 2010
Abstract Meta-analysis of 173 rate measurements from 21 publications was used to develop rate laws for chalcopyrite dissolution under environmentally relevant conditions. Multiple linear regression analysis of 28 data for nonoxidative chalcopyrite dissolution in the presence of O2 and Cl− produced the following rate law: r = 10 - 1.52
Bryn E. Kimball, J. Donald Rimstidt, Susan L. Brantley   +2 more
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Controlled Release with Finite Dissolution Rate

SIAM Journal on Applied Mathematics, 2011
We consider a two-phase generalization of the classical Higuchi model for controlled drug release. The drug is assumed to be prepared in a stent in its solid phase by immersion in a polymeric matrix, which eventually delivers the drug when it reaches the free end.
BISCARI, PAOLO, S. Minisini, PIEROTTI, DARIO GIANCARLO, VERZINI, GIANMARIA, ZUNINO, PAOLO   +4 more
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Dissolution Rates of Pure Nonionic Surfactants

Langmuir, 2000
no ...
Chen, B. H., Miller, C. A., Walsh, J. M., Warren, P. B., Ruddock, J. N., Garrett, P. R., Argoul, Françoise, Léger, Christophe   +7 more
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Precision Apparatus for Dissolution Rate Determinations

Journal of Pharmaceutical Sciences, 1964
An apparatus particularly useful for intrinsic dissolution rate determinations by the rotating disk method is described. It affords precision speed control, wide range of rotation rates, good shaft concentricity, and maintains constant speed over extended periods of time.
G, LEVY, W, TANSKI
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Variability of Zinc Oxide Dissolution Rates

Environmental Science & Technology, 2017
Zinc oxide (ZnO) is of widespread use for numerous applications, including many in the cosmetic industry. Thus, ZnO particles are quite likely to enter the environment. ZnO may be harmful because of the release of cytotoxic Zn2+ ions during dissolution reactions.
Monika Michaelis, Cornelius Fischer, Lucio Colombi Ciacchi, Andreas Luttge   +3 more
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