Distributions uniform

Fig. 1. Schematic diagrams of several possible capsule stmctures (a) continuous core/sheU microcapsule in which a single continuous sheU surrounds a continuous region of core material (b) multinuclear microcapsule in which a number of small domains of core material are distributed uniformly throughout a matrix of sheU material and (c) continuous core capsule with two different sheUs.

Poly(2,6-dimethyl-l54-phenylene oxide). It is well estabhshed that PS and PPO are miscible in all proportions and that the mbber particles from HIPS are distributed uniformly throughout the new mixed matrix. 

Falling Films When a hquid is distributed uniformly around the peripheiy at the top of a vertical tube (either inside or outside) and allowed to fall down the tube wall by the influence of gravity, the fluid... 

During filling, the catalyst is distributed uniformly to avoid the possibility of channeling that coiild lead to poor heat transfer, poor conversion, and harm to the catalyst because of hot spots. During startup, sudden surges of flow may disturb the bed and are to be avoided. For instance, in a study of a hydrodesulfuiizer by Murphree et al. (Ind. Eng. Chem. Proc. Des. size unit varied between 47 and 80 percent with different modes of loading and startup. 

Kira Hagstrom and Alexander Zhivov. Design algorithm for room air distribution design using jet theory and experimental data on temperature and velocity distribution uniformity. Draft, Espoo 14.09, 1998. 

Fuller claims that an auxiliary cupboard has better performance than an ordinary cupboard, if properly designed and used. The auxiliary flow rate should be 50% to 75% of the total exhaust flow from the cupboard. Below 50% there is no beneficial effect and above 75% the auxiliary air will aspirate contaminants out of the cupboard. The auxiliary air should enter the hood through the upper one-half to two-thirds of the opening. This should fill the volume between the cupboard operator and the opening and assist in the containment. The auxiliary air should be distributed uniformly across the length of the cupboard for a vertically sliding sash or above only the open sash of a cupboard with a horizontally sliding sash. It should also have a temperature within 1.5 °C of the room temperature and have a constant flow rate without pulsations. 

Area sources include die multitude of minor sources with individually small emissions diat are impractical to consider as separate point or line sources. Area sources are topically treated as a grid netw ork of square areas, widi pollutant emissions distributed uniformly within each grid square. Area source information required includes types and amounts of pollutant emissions, die... 

The analysis depends on whether the interfacial failure occurs by yielding or by crack propagation. The simplest analysis is based on interfacial yielding where the shear stress is assumed to be distributed uniformly over the interface from top to bottom. According to this analysis, the interfacial shear stress increases uniformly until every location in the interface gives way simultaneously. 

Enthalpy, Btu/unit flow 2,901.076 lb = 31.48 Feed temperature 90°F, liquid at stage 5 from top, Equimolal overflow not assumed Column Pressure 0.39 (top) to 0.86 (bottom) psia, distributed uniformly to each tray... 

The propriety of using the moisture content of the whole food substance as the critical variable is, however, open to question because the moisture within a given food is not distributed uniformly. The total moisture content is a sum of the moisture contents of the various components, such as starch, pectin, protein, sugar, and cellulose. 

Diffusion effects can be expected in reactions that are very rapid. A great deal of effort has been made to shorten the diffusion path, which increases the efficiency of the catalysts. Pellets are made with all the active ingredients concentrated on a thin peripheral shell and monoliths are made with very thin washcoats containing the noble metals. In order to convert 90% of the CO from the inlet stream at a residence time of no more than 0.01 sec, one needs a first-order kinetic rate constant of about 230 sec-1. When the catalytic activity is distributed uniformly through a porous pellet of 0.15 cm radius with a diffusion coefficient of 0.01 cm2/sec, one obtains a Thiele modulus y> = 22.7. This would yield an effectiveness factor of 0.132 for a spherical geometry, and an apparent kinetic rate constant of 30.3 sec-1 (106). 

Alloys are metallic materials prepared by mixing two or more molten metals. They are used for many purposes, such as construction, and are central to the transportation and electronics industries. Some common alloys are listed in Table 5.5. In homogeneous alloys, atoms of the different elements are distributed uniformly. Examples include brass, bronze, and the coinage alloys. Heterogeneous alloys, such as tin-lead solder and the mercury amalgam sometimes used to fill teeth, consist of a mixture of crystalline phases with different compositions. 

The diffusion of one liquid into another also demonstrates molecular motion. Figure 2 shows that if a drop of ink is added to a beaker of still water, the color slowly but surely spreads throughout the water. The water molecules and the molecules that give ink its color move continuously. As they slide by one another, the ink molecules eventually become distributed uniformly throughout the volume of liquid. 

After a drop of ink is added to a beaker of water (left), the ink diffuses slowly through the liquid (center) until eventually the ink is distributed uniformly (right). The molecular views indicate that the motion of ink molecules and water molecules is responsible for this diffusion. Ink molecules (red-violet circles) and water molecules (blue circles) move about continually, even after they are well mixed. 

How does a 1 2 mixture of O2 and He appear on the molecular level As O2 is added to the container, its molecules move throughout the volume and become distributed uniformly. Diffusion causes gas mixtures to become... 

When 8.0 mol of He is added to a diver s tank (a) the atoms quickly become distributed uniformly throughout the tank (Z>). When 4.0 mol of O2 is added to this tank (c) the molecules move about independently of the He... 

Sugar dissolves In water to give a solution that contains individual sugar molecules distributed uniformly among the water molecules. The aqueous sugar solution is stable and remains uniform indefinitely. Recall from Chapter 1 that a solution is a homogeneous mixture. On the microscopic scale, one microscopic portion of a solution looks the same as every other microscopic portion. 

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