Disintegrant comparison

A comparison of Fig. 4 and Fig. 3 shows that this uncoupled QCMD bundle reproduces the disintegration of the full QD solution. However, there are minor quantitative differences of the statistical distribution. Fig. 5 depicts... 

As can be seen even from the kinetic curves in Fig. 3, the type of impeller has a decisive influence on particle disintegration in stirred tanks. This is particularly clear from a comparison of other impeller systems on the basis of the reference particle diameter dp in Fig. 4. 

Figure 11 shows the reference floe diameter for viscometers as a function of shear stress and also the comparison with the results for stirred tanks. The stress was determined in the case of viscosimeters from Eq. (13) and impeller systems from Eqs. (2) and (4) using the maximum energy density according to Eq. (20). For r > 1 N/m (Ta > 2000), the disintegration performance produced by the flow in the viscosimeter with laminar flow of Taylor eddies is less than that in the turbulent flow of stirred tanks. Whereas in the stirred tank according to Eq. (4) and (16b) the particle diameter is inversely affected by the turbulent stress dp l/T, in viscosimeters it was found for r > 1.5 N/m, independently of the type (Searle or Couette), the dependency dp l/ pi (see Fig. 11). 

The diagram in Fig. 18 shows direct comparisons with the corresponding results for the floccular system. The particle diameters dpv and dp and the relative enzyme activity a/a in Fig. 18 show similar patterns of variation as with the specific impeller power P/V. It is therefore appropriate to represent these results by means of the correlation function obtained for the floccular system according to Eq. (20). As in Fig. 9, a clear correlation of the results is found for both systems (see Figs. 19 and 20). It is thus clear that particle disintegration in a stirred tank with baffles follows a similar pattern for other particle systems. 

For comparison. Fig. 21 also shows the dependence of the results on the circumferential velocity of the impeller. Contrary to many assumptions in the literature, this diagram indicates that velocity is not a significant process parameter as far as the disintegration process is concerned. 

The experimental results in Fig. 27 show the influence of the reactor system (see Fig. 28) on the disintegration of enzyme activity. It was found that the low-stress bladed impeller results in less activity loss than the propeller stirrer which causes much higher maximum energy dissipation ,. The gentle motion the blade impeller produces means that stress is so low that its disadvantage of worse micro mixing in NaOH (in comparison with the propeller) is more than compensated. 

Norman, R. D., Swartz, M. L., Phillips, R. W. Virmani, R. (1969). A comparison of the intraoral disintegration of three dental cements. Journal of the American Dental Association, 78, 777-82. 

We also conducted a combined scintigraphy and pharmacokinetic study in healthy volunteers, which allowed comparison of the in vivo rates of disintegration and gastric emptying... 

Tokuyama, E., Matsunaga, C., Yoshida, K., Mifsud, J.-C., Irie, T., Yoshida, M., and Uchida, T. (2009). Famotidine orally disintegrating tablets Bitterness comparison of original and generic products. Chem. Pharm. Bull. 57(4), 382-387. 

A 3 factorial design was used for the 4 variables studied disintegrant concentration (C), compression load (F), storage temperature (T) and storage relative humidity (R), at three levels each. Since the levels of each variable were not expressed in units of the same order, comparison of the extent of the contribution of the effect of the different variables was difficult. In order to be able to compare the effect of the different variables, the values of the variable levels were standardized (Table 8.1). 

Tablets were prepared either with an insoluble (dicalcium phosphate dihydrate), a soluble (6-lactose) or a moderately soluble filler-binder (a-lactose monohydrate). As a disintegrant four different starches (com, rice, potato and tapioca) were used. As a comparison the effect of two super-disintegrants (crospovidone and sodium starch glycolate) was studied. The disintegrants were added at two concentration levels. The compression load was adjusted in order to obtain tablets with comparable initial cmshing strengths.

A problem not mentioned in Chapter 15 is one that is very special for radioactive decay when the elapsed time given in the problem is insignificant in comparison with the half-life. Under such circumstances, Equation 26-2 is totally inappropriate, and the proper equation to use is Equation 26-1. In this case, consider —dN to be the number of atoms that disintegrate in a finite period of time df, which is negligible compared to q consider also that A remains constant during this same period of time. The following problem shows this application of Equation 26-1. 

Table 4 Drug B Comparison of Mean Hardness and Disintegration Times... 

Graham, D.Y., J.L. Smith, and A.A. Bouvet. 1990. What happens to tablets and capsules in the stomach Endoscopic comparison of disintegration and dispersion characteristics of two micro-encapsulated potassium formulations. J Pharm Sci 79 420. 

It is important to note that in the various studies reviewed in the preparation of this document, dose levels have been presented by those authors in several ways. In order to facilitate comparisons among studies, these levels have generally been converted to an equivalent dose in microcuries (p Ci) and kilo-Becquerels (kBq). The historical definition of one curie is the disintegration rate exhibited by one gram of radium. There are 0.027 pCi per kBq. In this document, comparisons are usually made between total administered amounts of radioactivity, in pCi/kg and kBq/kg, instead of using a daily dosage level. 

How can disintegration of the ionic liquids be avoided or reduced The cations of the ionic liquid have to be stabilized, e.g. via delocalisation of the positive charge, so that they are less eager for electron uptake in comparison to the dissolved metal... 

The 3H-inulin radioactivity is expressed as disintegrations per min per ml of plasma or per gram of tissue. Plasma 3H-inulin levels being dose-dependent increased after treatment are plotted versus time in comparison with control. 3H-Inulin content in the gastric wall is dose-dependent increased after treatment especially in the antrum region. 

Sawayanagi et al. [301] reported the fluidity and compressibility of combined powders, viz., lactose/chitin, lactose/chitosan, potato starch/chitin, potato starch/chitosan as well as the disintegration properties of tablets made from these powders in comparison with those of combined powders of lactose/MCC and potato starch/MCC. This was done in order to develop direct compression dilutents as a part of their studies on pharmaceutical applications of chitin and chitosan. 

NCO/OH=35%). The film samples under comparison were placed in the buffer aqueous solution at 37°C. The wet weight was periodically measured. The mass uptake kinetics of the cross-linked sample are shown in Figure 3, with the cross indicating the point at which the sample disintegrated completely, only a few tiny particles were present in the solution. 

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