C particle size distribution

Brown, C. Particle Size Distribution by Centrifugal Sedimentation, /. Phys. Chem, 1944, 48, 246. 

Fig. 6.11 (a) Particle size distribution curves for Cu powders obtained by potentiostatic electrodeposition on Pt electrodes, (b) particle size distribution curves for Cu powders obtained by galvanostatic electrodeposition on Pt electrodes. The surface area of the electrode 0.63 cm and (c) particle size distribution curves for Cu powders obtained by the potentiostatic and galvanostatic (the average current in the potentiostatic regime) electrodepositions on Cu electrodes. The surface area of the electrode 0.63 cm (Reprinted from Refs. [6, 7, 62] with kind permission from Springer)... 

Fig. 12.10 (a) High-resolution transmission electronic microscopy (HRTEM) of the Pd/Al203 catalyst (Toniolo et al.. Advanced Chemistry LettersVol. 1, pp. 1-8, 2012). (b) EDX analyses of the Pd/Al203 catalyst (Toniolo et al., Advanced Chemistry LettersVol. 1, pp. 1-8, 2012). (c) Particle size distribution of the 1.5 % Pd/Al203 catalyst (PdAl) (Toniolo et al.. Advanced Chemistry Letters Vol. 1, pp. 1-8, 2012) [26]... 

Bowen, P., Humphy-Baker, R., Herard, C, Particle Size Distribution Measurement of Regular Anisotropic Particles - Cylinders and Platelets, in Proc. World Congress Part. Technol. 3, Brighton, 1998, Paper No.29. 

Even the void fraction together with particle size distribution does not provide all of the necessary information on the kind of flow. The mutual forces between distinct particles depend not only on the distance between the particles but also on the surface properties of the particles. The strength of the attractive forces between particles depends on conditions. For instance, the moisture content of the solid is essential for determining the attractiv c forces between particles, especially for hydroscopic materials such as wood. Airflow between particles usually tends to separate particles, whereas the surface forces, adhesion forces, tend to bring them together. 

In principle, the velocities c and ti can be determined by taking a series of pictures at a very high frequency of the flow through a transparent plastic tube. Because of the particle size distribution, each particle moves at a different velocity, and this makes this method difficult to apply in practice. We have therefore used an indirect method, where we have measured the pressure losses of pneumatic conveying for two mixture ratios and then fit the parameters so that Eq, (14.126) coincides as accurately as possible with measured pressure losses. 

Chen, J., Zheng, C. and Chen, G., 1996. Interaction of macro- and micromixing on particle size distribution in reactive precipitation. Chemical Engineering Science, 51, 1957-1966. 

Petanate, A.M. and Glatz, C.E., 1983. Isoelectric precipitation of soy protein. I. Factors affecting particle size distributions. II. Kinetics of protein aggregate growth and breakage. Biotechnology and Bioengineering, 25, 3049. 

During the actual preparation of the GPC/SEC gel, there are several noteworthy items in the procedure. When combining aqueous and organic phases, always pour the organic phase into the water phase as the reverse procedure produces very large particles. This mixture must be held at 40°C to prevent the initiator from starting the reaction before the right size particles are formed. Rotor speed determines the particle size of the spheres the faster the speed the smaller the particles. Constant torque mixers produce the best results with more narrow particle-size distributions. The initial mixture should be stirred at 300-400 rpm to ensure a particle-size distribution from 2 to 20 yam. 

The carbon raw material in the form of coke, coal or natural or synthetic graphite is ground and sieved (following calcination at 700-1300°C to control volatiles, if necessary) to give a desired particle size distribution. The distribution depends upon the size of the artifact to be formed and the method of forming. 

Brown et al. [494] developed a method for the production of hydrated niobium or tantalum pentoxide from fluoride-containing solutions. The essence of the method is that the fluorotantalic or oxyfluoroniobic acid solution is mixed in stages with aqueous ammonia at controlled pH, temperature, and precipitation time. The above conditions enable to produce tantalum or niobium hydroxides with a narrow particle size distribution. The precipitated hydroxides are calcinated at temperatures above 790°C, yielding tantalum oxide powder that is characterized by a pack density of approximately 3 g/cm3. Niobium oxide is obtained by thermal treatment of niobium hydroxide at temperatures above 650°C. The product obtained has a pack density of approximately 1.8 g/cm3. The specific surface area of tantalum oxide and niobium oxide is nominally about 3 or 2 m2/g, respectively. 

Particle-Size Distribution 6 hours Drying limes 22 hours 44 hours regrinding to 40-mesh c, 44 hours... 

Data in Table I reveal that sieved fractions of different particle size distribution lose varying amounts of moisture dining the same drying period at 70° C. The last column in the table shows that the apparent percentage of moisture in the different frac-... 

Powdered Teflon for use in pyrots is covered by US Mil Spec MIL-P-48296IPA) (1 May 1974), Polytetrafluoroethylene (TFE) . Three classes of material are specified (1,2 3). The requirements are purity, 99.4% min infrared spectrum, peaks consistent with figure shown color, TFE shall be opaque and the color shall range from white to gray moisture, 0.05% max ash, 0.1% max mp, 337° 10°C packing density, Class 1 — 1.18 0.13g/cc, Class 2 - 1.25 0.02g/cc, Class 3- 1.14 0.09g/cc particle size by sieve analysis, Class 1 — 95 15 microns, Class 2 — 237 27 microns, Class 3 — 200 30 microns particle size distribution by sieve analysis, as specified in Table 1... 

Fig. 2. TEM images and the corresponding particle size distribution histograms of (a) 6 nm, (b) 7 nm, (c) 8 nm, (d) 9 nm, (e) 10 nm, (f) 11 nm, (g) 12 nm, and (h) 13 nm sized iron nanoparticles showing the one nanometer level increments in diameter. The scale bars at the bottom of the TEM images indicate 20 nm...

This paper will be limited to a discussion of our packed column studies in which we have addressed attention to questions regarding, (a) the role of ionic strength and surfactant effects on both HDC and porous packed column behavior, (b) the effects of pore size and pore size distribution on resolution, and (c) the effects of the light scattering characteristics of polystyrene on signal resolution and particle size distribution determination. 

Figure 5. Morphology and particle size distribution of an island silver thin film deposited on native oxide covered silicon (a) before ion bombardment and after (b) 0.5 keV Ar sputtering with 1.1 X 10, (c) 2.5 X 10, and (d) 3.9 x 10 ion/cm dose. Sputtering speed for silver was around 3-4ML/min. Total elapsed sputtering time is indicated on each size distribution graphs. (Reprinted from Ref [123], 2003, with permission from Springer.)...

Figure 16.6 TEM micrographs of titania-supported Au particles. The nominal thickness of An was (a) 0.13 nm (h) 0.78nm (c) 1.56nm (d) 2.33 nm. The Au deposition rate was 2.6 X 10 nms. Particle size distributions of Au for various deposition times are shown in the plot, with the distrihutions fitted to a normal Gaussian function.

The Pd-Sn/C catalysts (1 to 7.5% Pd containing 0 to 1% Sn) were heated under vacuum at 150°C and then exposed to hydrogen. These preactivated samples were then titrated with carbon monoxide, a veiy specific ligand for Pd, up to 800 Torr at 30°C. A general linear trend of carbon monoxide concentration with % Pd in Figure 15.3 indicates that the carbon monoxide adsorption is directly correlated to Pd concentration, as expected. The trend is independent of Sn content. This linear Pd-CO trend indicates that the particle size distribution is similar for the different catalysts. However, Figure 15.3 also indicates no relationship between % H2S irreversibly adsorbed and % Pd. 

Design a cyclone to recover solids from a process gas stream. The anticipated particle size distribution in the inlet gas is given below. The density of the particles is 2500 kg/m3, and the gas is essentially nitrogen at 150°C. The stream volumetric flow-rate is 4000 m3/h, and the operation is at atmospheric pressure. An 80 per cent recovery of the solids is required. 

Figure 11 Dissolution of two particle size distribution fractions of a water-insoluble drug (solubility in water at 37°C < 10 g/mL). Equation (41) was used to calculate the values shown by the dashed line, which represents the estimated dissolution of the drug based on the particle size distribution and solubility determined experimentally. 

Static(batch) and dynamic(flow) tests were carried out on toluene - extracted and peroxide - treated Wilmington oil field unconsolidated sands with dilute solutions of polyacrylamide (Dow Pusher-500) polymer in 1 wt% NaCl at 50° C and 1.5 ft./day, simulating reservoir temperature and flow rates. In the static tests, Ottawa sand, with particle size distributions similar to the Wilmington sand, were also used for comparison purposes. 

R. J. Hintz, K. C. Johnson. The effect of particle size distribution on dissolution rate and oral absorption. Int. J. Pharm. 1989, 53, 9-17. 

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