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Volume manifold

By Postulate I there is an energy transport associated with mass transport. By definition, V reflects the transport of the mass manifold through the volume manifold. Hence, the rate of energy transport with mass transport through the volume manifold is given by V, where is a second order tensor. Then... [Pg.210]

Furthermore, inasmuch as the availability contained by a volume manifold is the portion of the energy content of the manifold which could be transmitted out of the manifold were the "contained" manifolds brought to complete stable equilibrium, then the work flux of availability (through a particle) will be related to the work flux of energy by... [Pg.211]

Finally, FIA is an attractive technique with respect to demands on time, cost, and equipment. When employed for automated analyses, FIA provides for very high sampling rates. Most analyses can be operated with sampling rates of 20-120 samples/h, but rates as high as 1700 samples/h have been realized. Because the volume of the flow injection manifold is small, typically less than 2 mb, consumption of reagents is substantially less than with conventional methods. This can lead to a significant decrease in the cost per analysis. Flow injection analysis requires additional equipment, beyond that used for similar conventional methods of analysis, which adds to the expense of the analysis. On the other hand, flow injection analyzers can be assembled from equipment already available in many laboratories. [Pg.658]

Fig. 4. Schematic of a hemodialyzer. The design of a dialyzer is close to that of a sheU and tube heat exchanger. Blood enters through an inlet manifold, is distributed to a parallel bundle of fibers, and exits into a coUection manifold. Dialysate flows countercurrent in an external chamber the blood and dialysate are separated from the fibers by a polyurethane potting material. Housings are typically prepared from acrylate or polycarbonate. Production volume is... Fig. 4. Schematic of a hemodialyzer. The design of a dialyzer is close to that of a sheU and tube heat exchanger. Blood enters through an inlet manifold, is distributed to a parallel bundle of fibers, and exits into a coUection manifold. Dialysate flows countercurrent in an external chamber the blood and dialysate are separated from the fibers by a polyurethane potting material. Housings are typically prepared from acrylate or polycarbonate. Production volume is...
The principal requirement of a sampling system is to obtain a sample that is representative of the atmosphere at a particular place and time and that can be evaluated as a mass or volume concentration. Remote monitoring techniques are discussed in Chapter 15. The sampling system should not alter the chemical or physical characteristics of the sample in an undesirable manner. The major components of most sampling systems are an inlet manifold, an air mover, a collection medium, and a flow measurement device. [Pg.179]

The volume of the manifold and the sampling flow rate determine the time required for the gas to move from the inlet to the collection medium. This residence time can be minimized to decrease the loss of reactive species in the manifold by keeping the manifold as short as possible. [Pg.181]

Conventional Flare System - The majority of pressure relief valve discharges which must be routed to a closed system are manifolded into a conventional blowdown drum and flare system. The blowdown drum serves to separate liquid and vapor so that the vapor portion can be safely flared, and the separated liquid is pumped to appropriate disposal facilities. The blowdown drum may be of the condensible or noncondensible type, according to the characteristics of the streams entering the system. Selection criteria, as well as the design basis for each type of blowdown drum, are detailed later in this volume. The design of flares, including seal drums and other means of flashback protection, is described later. [Pg.207]

Gas-ring burners spray gas from orifices drilled in an annular manifold into a controlled-volume air stream. Combustion is initiated by an ignitor. [Pg.84]

Each solvent passes from its reservoir directly to a pump and from the pump to a mixing manifold. After mixing, the solvents pass to the sample valve and column. The pumps control the actual program and are usually driven by stepping motors. The volume delivery of each solvent is controlled by the speed of the respective pump. In turn, the speed of each motor is precisely determined by the frequency of its power supply which can be either generated by external oscillators or, if the chromatograph is computer controlled, directly from the computer itself. [Pg.126]

In line with these current developments, publishing a book dealing with the most recent achievements in this field is particularly timely. The volume is structured in chapters according to the type of metal complex. In every chapter, a brief introduction on the general chemical properties of the respective class of Fe-complexes will be given. Subsequently, representative examples for different catalytic transformations with a special emphasis on the various reaction manifolds will be presented. This structure implies that the reviews are not comprehensive but are meant to improve the understanding of the catalytic role a certain iron complex plays within the mechanism. [Pg.228]

Also a simulation of the flow field in the methanol-reforming reactor of Figure 2.21 by means of the finite-volume method shows that recirculation zones are formed in the flow distribution chamber (see Figure 2.22). One of the goals of the work focused on the development of a micro reformer was to design the flow manifold in such a way that the volume flows in the different reaction channels are approximately the same [113]. In spite of the recirculation zones found, for the chosen design a flow variation of about 2% between different channels was predicted from the CFD simulations. In the application under study a washcoat cata-... [Pg.177]

Place the Cig SPE column on the vacuum manifold, and prepare for extraction by washing the column sequentially three times with approximately 3-mL volumes of methanol and Optima water, respectively. Following the final water wash, allow a volume of liquid to remain on top of the resin bed, and avoid allowing the column to become dry before sample addition. [Pg.373]

Inspect the culture tubes in the manifold to determine if there is water in the organic eluent for any sample. If a water layer is present, quantitatively transfer the organic phase into a clean culture tube using a small amount of additional solvent as necessary. Return the culture tube containing the organic extract to its proper location in the manifold rack. Remove the Cig and sodium sulfate mbes, and reinstall the silica tubes on the manifold. With the sample remaining in the culture tube, continue to apply vacuum to the manifold to remove excess solvent. When the solvent volume is < 1 mL, discontinue vacuum, and allow the sample to return to room temperature. Adjust the sample volume in the culture mbe to 1 mL with isooctane-ethyl acetate (9 1, v/v). Transfer the entire sample into an autosampler vial for GC/MS analysis. Sample extracts may be stored for up to 1 month in a refrigerator (< 10 °C) before analysis. [Pg.374]

If high heat-transfer rates are required, small-diameter tubes are used to increase the surface area to volume ratio. Several tubes may be arranged in parallel, connected to a manifold or fitted into a tube sheet in a similar arrangement to a shell and tube heat exchanger. For high-temperature reactions the tubes may be arranged in a furnace. [Pg.485]

The benzene strip or extract solutions are evaporated nearly to dryness in 500-ml. standard-taper Erlenmeyer flasks on 3 units of a 6-unit variable heat extraction apparatus hot plate (see Figure 1). Evaporation is hastened by directing a jet of air at the surface of the benzene, gentle enough to avoid spattering when maintained 0.5 inch above the surface of the liquid. The benzene vapors are removed through a manifold connected to the house vacuum. On this apparatus 250 ml. of sample can be reduced to a volume of about 5 ml. in 10 minutes. [Pg.91]

The completion of this volume marks the happy milestone for me of a 15-year editorial association with Academic Press. It is appropriate, therefore, to acknowledge the professionalism of the staff and management, as well as their manifold contributions to the success of these volumes. It also marks my embarkation on new and more challenging professional pursuits. These ultimately will allow more opportunity to continue to perform the editorial tasks associated with Advances in Clinical Chemistry, as well as other educational and scientific activities. [Pg.258]

It is possible, however, to avoid any violation of these fundamental properties, and derive a result on the local electron densities of non-zero volume subsystems of boundaryless electron densities of complete molecules [159-161]. A four-dimensional representation of molecular electron densities is constructed by taking the first three dimensions as those corresponding to the ordinary three-space E3 and the fourth dimension as that representing the electron density values p(r). Using a compactifi-cation method, all points of the ordinary three- dimensional space E3 can be mapped to a manifold S3 embedded in a four- dimensional Euclidean space E4, where the addition of a single point leads to a compact manifold representation of the entire, boundaryless molecular electron density. [Pg.67]

The non-degenerate ground state electron density p/(r) over any subset d of manifold S3, S3 zd d, where subset d has non-zero volume on S3, determines uniquely... [Pg.67]


See other pages where Volume manifold is mentioned: [Pg.112]    [Pg.208]    [Pg.209]    [Pg.112]    [Pg.208]    [Pg.209]    [Pg.496]    [Pg.496]    [Pg.459]    [Pg.431]    [Pg.433]    [Pg.249]    [Pg.282]    [Pg.253]    [Pg.486]    [Pg.1111]    [Pg.2225]    [Pg.187]    [Pg.426]    [Pg.1233]    [Pg.36]    [Pg.136]    [Pg.331]    [Pg.523]    [Pg.523]    [Pg.403]    [Pg.658]    [Pg.41]    [Pg.178]    [Pg.374]    [Pg.824]    [Pg.1157]   
See also in sourсe #XX -- [ Pg.208 ]




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