Mixture ordered

The effect of carrier particle properties on the dissolution rate from ordered mixtures. Int J Pharm 28 23-31, 1986. 

M Westerberg, C Nystrom. Physicochemical aspects of drug release. XVII. The effect of drug surface area coverage to carrier materials on drug dissolution from ordered mixtures. Int J Pharm 90 1-17, 1993. 

For ternary and higher order mixtures, we have usually assumed that the interaction parameters for the non-water binary pairs in the water rich phase are identical to the vapor (hydrocarbon rich liquid phase) interaction parameters. Some work has been done on changing all water phase interaction parameters we concluded that predicted results were not improved enough to warrant the expenditure of time required to develop the additional parameters. A third interaction parameter for the hydrocarbon rich liquid could also be determined. Again, our work indicated that little improvement resulted from using this third parameter. Additional work is being done on both points. 

R. Lieckfeldt, J. Villalain, J.-C. Gomez-Fernandez, and G. Lee. Apparent pK(a) of the fatty acids within ordered mixtures of model human stratum corneum lipids. Pharm. Res. 12 1614-1617 (1995). 

In the case of ternary or higher-order mixtures, solution of the Gibbs-Duhem equation is again based on application of the properties of the exact differentials (Lewis and Randall, 1970) ... 

So far, we have seen several ways of calculating the Gibbs free energy of a two-component mixture. To extend calculations to ternary and higher-order mixtures, we use empirical combinatory extensions of the binary properties. We summarize here only some of the most popular approaches. An extended comparative appraisal of the properties of ternary and higher-order mixtures can be found in Barron (1976), Grover (1977), Hillert (1980), Bertrand et al. (1983), Acree (1984), and Fei et al. (1986). 

Thereafter, the dynamic mixing behaviors of fine cohesive particles adhered to the surface of a coarser excipient was discussed as considerable importance in the manufacture of solid pharmaceuticals (3). The term ordered mixing was given to this phenomenon by Hersey (4). An ordered mixture can be produced by a dry process, simple dry mixing of fine and coarse particles. When interparticle interactions, such as van der Waals and coulombic forces, exist between the two types of particles, the fine particle adheres to the surface of the coarse particle that is, an ordered mixture spontaneously forms. As described earlier, ordered mixing... 

For future theoretical developments in the field of transport properties of binary and higher-order mixtures, the simplest case seems to study the influence of the variation in mass of one of the species on the transport properties. Without a full understanding of this pure mass effect on the transport properties, it is not possible to analyze the effect of the translational-rotational coupling in real molecules. Toward this goal the simplest system that can be considered is a binary mixture at infinite solute dilution where the effect of the solute-solvent mass ratio on the solute diffusion can be studied. 

Random and Ordered Mixtures The accompanying figure shows two samples of mixtures of black-and-white squares. One is a black-and-white checkered board and the other was obtained by tossing a coin for each square if it showed heads, the square was colored black, (a) If we take a large number of black-and-white particles of equal numbers and place the mixture in a V-blender, which sample will the mixture resemble (b) If we take a large number of small testing samples from sample 1 and sample 2, and measure the fraction of black particles in each sample, what type of distribution would be expected in each case (c) What is the variance of each distribution ... 

Mort PR, Riman RE. 1995. Determination of homogeneity scale in ordered and partially ordered mixtures. Powder Technol. 82 93-104. 

Stephenson PL, Thiel WJ. 1980. The effect of humidity on the production of ordered mixtures. Powder Technol. 25 115-119. 

Hersey JA. 1977. Preparation and properties of ordered mixtures. Aust. J. Pharm. Sci. 6 29-31. 

Westerberg, M., and Nystrom, C. (1991), Physicochemical aspects of drug release. XII. The effect of some carrier particle properties and lubricant admixture on drug dissolution from tableted ordered mixtures, Int. I. Pharm., 69,129-141. 

Just as the first-order mixture model has a different form from that for independent variables, so does the seeond-order design ... 

Powder Mixtures. Powder mixtures could be ran-domP - or ordered mixtures. ° The latter were later on called interactive mixtures owing to the fact that they are not of a higher degree of order. 

Egermann, H. Orr, N.A. Ordered mixtures—interactive mixtures. Powder Technol. 1983, 36, 117-118. 

Ohta KM. Fuji M, Chikazawa M. Effect of geometric structure of flow promoting agents on the flow properties of pharmaceutical powder mixture. Pharm Res 2003 20(5) 804—9. Swaminathan V. Kildsig D. The effect of particle morphology on the physical stability of pharmaceutical powder mixtures The effect of surface tou ness of the carrier on the stability of ordered mixtures. Drug Dev Ind Pharm 2000 26(4) 365. 

Ordered mixing is a process in which particles are created that are a combination of two or more components of a blend. The ordered unit is the smallest entity that constitutes an ordered mixture. Below this size, it would only be possible to sample an incomplete unit or even a single ingredient. 

During the production of an ordered mixture, sufficient energy must be input by the blender to break down agglomerates of the fine cohesive component, which are then adhered to the surface of the carrier particles (40) The formation of ordered mixes can occur by mechanical ordering, adhesional ordering, or the production of coated ordered mixtures. 

One way to test an ordered mixture is to pass the blend through a nest of sieves and assay each particle size fraction. The lesser the variation in potency across the cuts, the better the ordered mix. Note that this test is highly dependent upon how much energy goes into the sieving process. Shaking the sieves by hand would be expected to produce different results than using an ultrasonic method. 

Stephenson P, Thiel W. The mechanical stability of ordered mixtures when fluidized and their pharmaceutical application. Powder Technol 1980 26 225-7,... 

Binders are just one of the critical excipients for a successful wet granulation formulation, as they are used to create an ordered mixture of all the ingredients by creating a cohesive network. While more than 30 different materials have been studied over the years, currently there are only about a dozen binders that are commonly used as granulating agents and these can be subdivided into three main categories, (/ sugars such as... 

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