Big Chemical Encyclopedia

Chemical substances, components, reactions, process design ...

Articles Figures Tables About

Figures—continued sizing

Figure 8. Size Exclusion Chromatography peak average diameters for the continuous run (17). (02 = residence time in the second reactor of the continuous train). Figure 8. Size Exclusion Chromatography peak average diameters for the continuous run (17). (02 = residence time in the second reactor of the continuous train).
Since most continuous size analyzers require a constant volume flowrate, further subdivision is often necessary. Osborne s solution (Figure 1.35b) was to feed the sample stream to a well-agitated tank and withdraw a representative sample at a constant flow-rate. [Pg.36]

By using the function ns Dp) we implicitly assume that the number distribution is no longer a discrete function of the number of molecules but a continuous function of the diameter Dp. This assumption of a continuous size distribution is valid beyond a certain number of molecules, say, around 100. In the atmosphere most of the particles have diameters smaller than 0.1 pm and the number distribution function n (Dp) usually exhibits a narrow spike near the origin (Figure 8.4). [Pg.354]

A suspension containing many particles of various sizes can be said to have a continuous size distribution. In fact, this particle size distribution may be the most important physical characteristic of the system. A cumulative size distribution is illustrated in Figure 1 cumulative number concentration (N) is plotted as a function of particle size expressed in volumetric units (v). Here N (number/cm ) denotes the total concentration of particles with a size equal to or less than v (/xm ) the total concentration of all particles is given by N. The slope of this curve, AIV/Au or dN/dv, is called a particle size distribution function and is represented as n(v). In this case n(v) has units of number/cm... [Pg.354]

FIGURE 7.1 (continued) Size matters, (c) Overview of water metabolism in cells. Transport of water across... [Pg.779]

As demonstrated by the graphs of Figure 8.8 one can in some circumstances deal with bimodal distributions which are well separated. A wide ranging continuous size distribution is difficult to characterize by PCS. In general, PCS is an applicable method from 0.003 to several microns. As in many other methods, data for non spherical particles use the size of an equivalent sphere diameter in the presentation of the data. [Pg.246]

Figure C2.17.2. Transmission electron micrograph of a gold nanoneedle. Inverse micelle environments allow for a great deal of control not only over particle size, but also particle shape. In this example, gold nanocrystals were prepared using a photolytic method in surfactant-rich solutions the surfactant interacts strongly with areas of low curvature, thus continued growth can occur only at the sharjD tips of nanocrystals, leading to the fonnation of high-aspect-ratio nanostmctures [52]. Figure C2.17.2. Transmission electron micrograph of a gold nanoneedle. Inverse micelle environments allow for a great deal of control not only over particle size, but also particle shape. In this example, gold nanocrystals were prepared using a photolytic method in surfactant-rich solutions the surfactant interacts strongly with areas of low curvature, thus continued growth can occur only at the sharjD tips of nanocrystals, leading to the fonnation of high-aspect-ratio nanostmctures [52].
Let be a well-defined finite element, i.e. its shape, size and the number and locations of its nodes are known. We seek to define the variations of a real valued continuous function, such as/, over this element in terms of appropriate geometrical functions. If it can be assumed that the values of /on the nodes of Oj, are known, then in any other point within this element we can find an approximate value for/using an interpolation method. For example, consider a one-dimensional two-node (linear) element of length I with its nodes located at points A(xa = 0) and B(a b = /) as is shown in Figure 2.2. [Pg.20]

In order to maintain a definite contact area, soHd supports for the solvent membrane can be introduced (85). Those typically consist of hydrophobic polymeric films having pore sizes between 0.02 and 1 p.m. Figure 9c illustrates a hoUow fiber membrane where the feed solution flows around the fiber, the solvent—extractant phase is supported on the fiber wall, and the strip solution flows within the fiber. Supported membranes can also be used in conventional extraction where the supported phase is continuously fed and removed. This technique is known as dispersion-free solvent extraction (86,87). The level of research interest in membrane extraction is reflected by the fact that the 1990 International Solvent Extraction Conference (20) featured over 50 papers on this area, mainly as appHed to metals extraction. Pilot-scale studies of treatment of metal waste streams by Hquid membrane extraction have been reported (88). The developments in membrane technology have been reviewed (89). Despite the research interest and potential, membranes have yet to be appHed at an industrial production scale (90). [Pg.70]

The dominant crystal size, is most often used as a representation of the product size, because it represents the size about which most of the mass in the distribution is clustered. If the mass density function defined in equation 33 is plotted for a set of hypothetical data as shown in Figure 10, it would typically be observed to have a maximum at the dominant crystal size. In other words, the dominant crystal size is that characteristic crystal dimension at which drajdL = 0. Also shown in Figure 10 is the theoretical result obtained when the mass density is determined for a perfectiy mixed, continuous crystallizer within which invariant crystal growth occurs. That is, mass density is found for such systems to foUow a relationship of the form m = aL exp —bL where a and b are system-dependent parameters. [Pg.348]

GLS Fluidized with a Stable Level of Catalyst Only the fluid mixture leaves the vessel. Gas and liquid enter at the bottom. Liquid is continuous, gas is dispersed. Particles are larger than in bubble columns, 0.2 to 1.0 mm (0.008 to 0.04 in). Bed expansion is small. Bed temperatures are uniform within 2°C (3.6°F) in medium-size beds, and neat transfer to embedded surfaces is excellent. Catalyst may be bled off and replenished continuously, or reactivated continuously. Figure 23-40 shows such a unit. [Pg.2120]

The manifestation of turbulent eddies is gustiness and is displayed in the fluctuations seen on a continuous record of wind or temperature. Figure 19-3 displays wind direction traces during (a) mechanical and (b) thermal turbulence. Fluctuations due to mechanical turbulence tend to be quite regular that is, eddies of nearly constant size are generated. The eddies generated by thermal turbulence are both larger and more variable in size than those due to mechanical turbulence. [Pg.294]

Consider a thin layer solid bowl centrifuge as shown in Figure 4.20. In this device, particles are flung to the wall of the vessel by centrifugal force while liquor either remains stationary in batch operation or overflows a weir in continuous operation. Separation of solid from liquid will be a function of several quantities including particle and fluid densities, particle size, flowrate of slurry, and machine size and design (speed, diameter, separation distance, etc.). A relationship between them can be derived using the transport equations that were derived in Chapter 3, as follows. [Pg.109]


See other pages where Figures—continued sizing is mentioned: [Pg.47]    [Pg.202]    [Pg.260]    [Pg.702]    [Pg.49]    [Pg.2908]    [Pg.218]    [Pg.118]    [Pg.199]    [Pg.239]    [Pg.509]    [Pg.407]    [Pg.229]    [Pg.547]    [Pg.131]    [Pg.394]    [Pg.87]    [Pg.6]    [Pg.445]    [Pg.416]    [Pg.527]    [Pg.520]    [Pg.231]    [Pg.258]    [Pg.9]    [Pg.200]    [Pg.137]    [Pg.1219]    [Pg.2384]    [Pg.2388]    [Pg.612]    [Pg.869]    [Pg.136]    [Pg.274]    [Pg.360]    [Pg.346]    [Pg.254]   
See also in sourсe #XX -- [ Pg.352 , Pg.353 , Pg.355 ]




SEARCH



Figures—continued

© 2024 chempedia.info