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Special solution

Aqueous Solution Viscosity. A special solution preparation method is used for one type of measurement of aqueous solution viscosity (96). The appropriate amount of poly(ethylene oxide) resin is dispersed in 125 mL of anhydrous isopropyl alcohol by vigorous stirring. Because the resin is insoluble in anhydrous isopropyl alcohol, a slurry forms and the alcohol wets the resin particles. An appropriate amount of water is added and stirring is slowed to about 100 rpm to avoid shear degradation of the polymer. In Table 4, the nominal resin concentration reported is based on the amount of water present and ignores the isopropyl alcohol. [Pg.343]

The strategies discussed in the previous chapter are generally applicable to convection-diffusion equations such as Eq. (32). If the function O is a component of the velocity field, the incompressible Navier-Stokes equation, a non-linear partial differential equation, is obtained. This stands in contrast to O representing a temperature or concentration field. In these cases the velocity field is assumed as given, and only a linear partial differential equation has to be solved. The non-linear nature of the Navier-Stokes equation introduces some additional problems, for which special solution strategies exist. Corresponding numerical techniques are the subject of this section. [Pg.156]

In most cases the only appropriate approach to model multi-phase flows in micro reactors is to compute explicitly the time evolution of the gas/liquid or liquid/ liquid interface. For the motion of, e.g., a gas bubble in a surrounding liquid, this means that the position of the interface has to be determined as a function of time, including such effects as oscillations of the bubble. The corresponding transport phenomena are known as free surface flow and various numerical techniques for the computation of such flows have been developed in the past decades. Free surface flow simulations are computationally challenging and require special solution techniques which go beyond the standard CFD approaches discussed in Section 2.3. For this reason, the most common of these techniques will be briefly introduced in... [Pg.230]

First prototypes have been built of separate water cooled exchanger plates, based on polypropylene double plates, which have been developed and tested within the last years. Since 1997 the tests has shown very satisfying results. A special coating of the plates and a special solution distribution element (no sprays are used) provide a uniform and almost complete coverage of the surface by the solution. [Pg.436]

A reactive transport model in a more general sense treats a multicomponent system in which a number of equilibrium and perhaps kinetic reactions occur at the same time. This problem requires more specialized solution techniques, a variety of which have been proposed and implemented (e.g., Yeh and Tripathi, 1989 Steefel and MacQuarrie, 1996). Of the techniques, the operator splitting method is best known and most commonly used. [Pg.306]

Despite advances in MILP solution methods, problem size is still a major issue since scheduling problems are known to be NP-hard (i.e., exponential increase of computation time with size in worst case). While effective modeling can help to overcome to some extent the issue of computational efficiency, special solution strategies such as decomposition and aggregation are needed in order to address the ever increasing sizes of real-world problems. [Pg.182]

Derived from spray dafa for water, kerosene, and special solutions over a broad range of air and liquid properties using lightscattering technique... [Pg.265]

Wijs Iodine monochloride solution analychem A solution In glacial acetic acid of iodine monochloride used to determine iodine numbers. Also known as Wljs special solution. vTs T-3,dTn man-3 kl6r,Td sa.Iu-shan )... [Pg.402]

Wijs special solution See Wijs iodine monochloride solution. vTs spesh-al sa.lti-... [Pg.402]

Here the a, and b, are a collection of constants that are uniquely determined by the initial positions and velocities of the atoms. This means that the normal modes are not just special solutions to the equations of motion instead, they offer a useful way to characterize the motion of the atoms for all possible initial conditions. If a complete list of the normal modes is available, it can be viewed as a complete description of the vibrations of the atoms being considered. [Pg.118]

Every example of a vibration we have introduced so far has dealt with a localized set of atoms, either as a gas-phase molecule or a molecule adsorbed on a surface. Hopefully, you have come to appreciate from the earlier chapters that one of the strengths of plane-wave DFT calculations is that they apply in a natural way to spatially extended materials such as bulk solids. The vibrational states that characterize bulk materials are called phonons. Like the normal modes of localized systems, phonons can be thought of as special solutions to the classical description of a vibrating set of atoms that can be used in linear combinations with other phonons to describe the vibrations resulting from any possible initial state of the atoms. Unlike normal modes in molecules, phonons are spatially delocalized and involve simultaneous vibrations in an infinite collection of atoms with well-defined spatial periodicity. While a molecule s normal modes are defined by a discrete set of vibrations, the phonons of a material are defined by a continuous spectrum of phonons with a continuous range of frequencies. A central quantity of interest when describing phonons is the number of phonons with a specified vibrational frequency, that is, the vibrational density of states. Just as molecular vibrations play a central role in describing molecular structure and properties, the phonon density of states is central to many physical properties of solids. This topic is covered in essentially all textbooks on solid-state physics—some of which are listed at the end of the chapter. [Pg.127]

N). The normal modes are the special solutions to the equations of motion that have the form... [Pg.139]

The roots of quadratic and cubic equations are well known as algebraic expressions of the equation s coefficients, and hence this section is comletely disconnected from the rest of the chapter. Nevertheless, these simple problems are so frequently encountered that we cannot ignore their special solutions. [Pg.71]

In linear programming problems we will need special solutions of matrix equations with "free" variables set to zero. These are called basic solutions of a matrix equation, where rank(A) is less than the number of variables. [Pg.330]

A number of other special solutions to the diffusion equations may be found in the literature. A few of these are mentioned here ... [Pg.227]

However, it has been demonstrated that the separation of HIPS and ABS is possible by using special solutions. A solution is used with the appropriate density, surface tension, and pH, such as acetic acid and water or hydrochloric acid, salt, surfactant and water. [Pg.288]

Diffusion into a sphere represents a three-dimensional situation thus we have to use the three-dimensional version of Fick s second law (Box 18.3, Eq. 1). However, as mentioned before, by replacing the Cartesian coordinates x,y,z by spherical coordinates the situation becomes one-dimensional again. Eq. 3 of Box 18.3 represents one special solution to a spherically symmetric diffusion provided that the diffusion coefficient is constant and does not depend on the direction along which diffusion takes place (isotropic diffusion). Note that diffusion into solids is not always isotropic, chiefly due to layering within the solid medium. The boundary conditions of the problem posed in Fig. 18.6 requires that C is held constant on the surface of the sphere defined by the radius ra. [Pg.795]

In medical applications, the dialysis SPM may be the patient s own stomach lining. A prepared solution is infused into the abdomen, stimulating osmotic flow of toxins across the stomach lining into the ingested solution, which is subsequently drained from the stomach. Alternatively, the dialyzer for blood dialysis (hemodialysis) may be a prepared membrane with special solution over which the blood flows to osmotically remove impurities. [Pg.260]

In the foregoing, the expressions needed to account for mass transport of O and R, e.g. eqns. (23), (27), (46), and (61c), were introduced as special solutions of the integral equations (22), giving the general relationship between the surface concentrations cG (0, t), cR (0, t) and the faradaic current in the case where mass transport occurs via semi-infinite linear diffusion. It is worth emphasizing that eqns. (22) hold irrespective of the relaxation method applied. Of course, other types of mass transport (e.g. bounded diffusion, semi-infinite spherical diffusion, and convection) may be involved, leading to expressions different from eqns. (22). [Pg.263]

Since eukaryotic chromosomes are linear, the ends of these chromosomes require a special solution to ensure complete replication. This can be seen in figure 26.26. At the very end of a linear duplex a primer is necessary to initiate DNA replication. After RNA primer removal there is bound to be a gap at the 5 end of the newly synthesized DNA chains. Since DNA synthesis always requires a primer the usual way of filling this gap is not going to solve the problem. This dilemma is overcome by a special structure at the ends (telomeres) of eukaryotic chromosomes and a special type of reverse transcriptase (telomerase) that synthesizes telomeric DNA. In many eukaryotes the telomeres contain short sequences (frequently hexamers) that are tan-demly repeated many times. Telomerase contains an RNA that binds to the 3 ends and also serves as a template for the extension of these ends. Prior to replication, the 3 ends of the chromosome are extended with additional tandemly repeated hexamers. The 3 ends are extended sufficiently so that there is room to accommodate an RNA primer. In this way there is no net loss of DNA from the 5 ends as a result of replication. After replication the 3 end is somewhat... [Pg.673]

Therefore the Proca equation can be recovered on the 0(3) level from the special solution (236) as the operator equation ... [Pg.41]

The time required to titrate a single sample may vary somewhat depending upon the nature of the sample and what determinations are requested. An average of about one hour is needed to run a single sample however, the time per sample may be less when a series of similar samples are run consecutively. If special solutions have to be prepared, an additional two hours may be required for the first sample in the series. [Pg.79]

Models can have the characteristic of different types and sizes of equation sets relative to a general set of algebraic equations. Some common example situations include physical property models and models containing differential equations. In posing the mathematical problem to be solved, a completely simultaneous solution approach can be used or a "mixed mode" that combines specialized solution techniques within the overall EO approach. [Pg.131]

While SAP dominates the ERP vendor landscape, the CRM provider and solution landscape is much more diverse. The big players such as Siebel and SAP cover more than 30 percent of the market, but there is a wide range of vendors serving niche and mid-tier markets or simply providing specialized solutions for indus-... [Pg.307]

Seme special solutions associated with the group structure (3) have been studied by two of us [HUB84, PAA85,HUB85a]. ... [Pg.24]


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