Particle size dependence loading

This research has given insight to a very unique bicontinuous blend system. It has also shown that the pore structure and release rates from EVAc matrices are not only dependent on particle size and loading but also on the blending technique. It becomes apparent that it is possible to tailor these systems not only for release rates but also for initial time of release of insoluble biologically active agents. 

Kawashima Y, Takeuchi H, Hino T, et al. Low-substituted hydroxypropylcellulose as a sustained-drug release matrix base or disintegrant depending on its particle size and loading in formulation. Pharm Res 1993 10(3) 351—355. 

For a protein incorporated in a matrix, the rate of release (i.e., the effective diffusion coefficient and Ft) depends on the molecular weight of the protein, the size of the dispersed particles, the loading, and the molecular weight of the polymer. For example, matrices of EVAc containing dispersed particles of bovine serum albumin (BSA) release protein for an extended period (Figure 9.11). The rate of release from the matrix depends on BSA loading (the number of BSA particles dispersed per unit volume of matrix) and BSA particle size. The rate of release from these matrices can be characterized by an effective diffusion coefficient or tortuosity, which must depend on the characteristics (i.e., particle size and loading) of the device. Tables 9.2 and 9.3 list the tortuosity values calculated from fits of the desorption equation to available literature data of protein release from EVAc slabs. 

It is possible to prepare various kinds of nanoparticles with different surface charges and particle sizes depending on the polymer composition and preparation technique. As a result, the particle size of nanoparticles varies from 10 nm to 200 nm and the surface charge - -5 mV to -1-50 mV. In this manner, drug carrier systems can be formed through different routes such as oral, parenteral and other mucosal routes for local or systemic therapy, with high cellular interaction, loading capacity, transfection efficiency and low toxicity. 

The specific rate of mass transfer for any of the controlling regimes may then be solved easily.Depending on the particle size and loading,it may well be that the bulk liquid is saturated with respect to the dissolved solid species.However,even the case of "finite" slurry,which has a bulk concentration lower than the saturation concentration,can be solved analytically.For instance, for the case of an instantaneous reaction, the following equation holds in the absence of any gas-side resistance ... 

The stmcture of the electrochemical interface depends on the particle size, the loading and the active surface area of the caibon supported Pt particles. In addition for the case of HT PEMFCs the amount of H3PO4 plays a predominant role on the performance by affecting both the stmcture and the catalytic properties of the electrochemical interface. 

When smaller particles are used, the peak broadening caused by loading is clearly higher than with bigger ones. The selection of the particle size depends, of course, on the given separation and is normally a compromise between resolution, loadability, and the possible pressure and flow rate ranges. In the... 

The size of metal particles in cogelled catalysts has been examined extensively [24, 28, 30, 32, 33, 39, 40, 109, 152]. Often, metal particles are distributed into two families of different size a majority of small nanoparticles in the range 2-5 nm (small black points in Fig. 7) and a few large particles in the range 10-100 nm (four large black points in Fig. 7). Metal particle size depends on metal nature and loading as well as on many synthesis variables. By optimizing the latter ones, it is however possible to obtain small nanoparticles only with a narrow size distribution (2-3 nm) [40]. 

The filter application is typically applied to handling streams containing less than 100 to 200 mg/Liter suspended solids, depending on the required effluent level. Increased-suspended solids loading reduces the need for frequent backwashing. The suspended solids concentration of the filtered liquid depends on the particle size distribution, but typically, granular media filters are capable of producing a... 

To achieve the desired cast density for Octol of 1.8g/cc it is necessary that the ratio of HMX TNT be 3 1. However, at this ratio the apparent viscosity, or efflux, is strongly dependent on the polymorphic variety of HMX used and on its particle size distribution. In the initial pilot production of Octol (Ref 3) it was found that for the desired efflux of < 15 sec, 60—70% of the solid HMX must consist of the beta-polymorph having particle diameters in the range of 500—800 microns. Such precise control of particle size was not possible at that time and early Octol casts were made at approximately 50 secs efflux. The economical production of Octol with a satisfactorily short efflux time continues to present a problem in loading shells with this expl (Refs 4, 11 29)... 

In this equation, Summerfield has shown that the parameter b1 should be very sensitive to the flame temperature of the propellant. At the same time, the factor b2 should be strongly dependent on oxidizer particle size. To check these predictions, Summerfield prepared four propellants using 120 and 16 oxidizer particles at 75 and 80% loadings. Correlation of the burning-rate data with Eq. (39) yields the values for the parameters given in Table I. The experimentally observed trends are consistent with predicted effects. 

An example for a non-structure-sensitive reaction is provided by Davis et al. [102], who investigated the liquid-phase hydrogenation of glucose over carbon and silica based ruthenium catalysts with particle sizes between 1.1 and 2.4 run. Depending on catalyst loading which was between 0.56 wt.% and 5 wt.%, dispersion decreased from 91% to 43%. At the same time, TOFs varied only insignificantly in a range between 0.21 1/s and 0.32 1/s. 

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