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Practical Solutions

Many improvements were implemented, and not all of them are appropriate to describe here. The underlying approach was to simplify the physical process and make the information flow more visible and directly connected to those who did the work. [Pg.479]

In this case, trying to use very sophisticated planning and execution management systems to manage the supply chain proved very un-robust. Increasing [Pg.338]


In principle, Chen, given the flux relations there is no difficulty in constructing differencial equations to describe the behavior of a catalyst pellet in steady or unsteady states. In practice, however, this simple procedure is obstructed by the implicit nature of the flux relations, since an explicit solution of usefully compact form is obtainable only for binary mixtures- In steady states this impasse is avoided by using certain, relations between Che flux vectors which are associated with the stoichiometry of Che chemical reaction or reactions taking place in the pellet, and the major part of Chapter 11 is concerned with the derivation, application and limitations of these stoichiometric relations. Fortunately they permit practicable solution procedures to be constructed regardless of the number of substances in the reaction mixture, provided there are only one or two stoichiomeCrically independent chemical reactions. [Pg.5]

Vgiec and Vxc represent the electron-nuclei, electron-electron and exchange-correlation dionals, respectively. The delta function is zero unless G = G, in which case it has lue of 1. There are two potential problems with the practical use of this equation for a croscopic lattice. First, the summation over G (a Fourier series) is in theory over an rite number of reciprocal lattice vectors. In addition, for a macroscropic lattice there effectively an infinite number of k points within the first Brillouin zone. Fortunately, e are practical solutions to both of these problems. [Pg.174]

Most of the problems in this book are simple. Many of the methods used have been known for decades or for centuries. At the machine level, individual steps in the procedures are at the grade school level of sophistication, like adding two numbers or comparing two numbers to see which is larger. What makes them hard is that there are very many steps, perhaps many millions. The computer, even the once lowly microcomputer, provides an entry into a new scientific world because of its incredible speed. We are now in the enviable position of being able to arrive at practical solutions to problems that we could once only imagine. [Pg.1]

Changing the constants in the SCF equations can be done by using a dilferent basis set. Since a particular basis set is often chosen for a desired accuracy and speed, this is not generally the most practical solution to a convergence problem. Plots of results vs. constant values are the bifurcation diagrams that are found in many explanations of chaos theory. [Pg.194]

General problems with synthetic organic reactions are discussed together with some practical solutions for specific examples. These problems include 9 regio- and stereoselectivity by exploitation of the substrates stereochemistry (e.g., p. 20ff.) and differentiated nucleophilicity (p. 24f, 44f, 56ff.)... [Pg.4]

Microemulsions or solubilized or transparent systems are very important ia the marketing of cosmetic products to enhance consumer appeal (32,41). As a rule, large quantities of hydrophilic surfactants are required to effect solubilization. Alternatively, a combination of a solvent and a surfactant can provide a practical solution. In modem clear mouthwash preparations, for example, the flavoring oils are solubilized in part by the solvent (alcohol) and in part by the surfactants. The nature of solubilized systems is not clear. Under normal circumstances, microemulsions are stable and form spontaneously. Formation of a microemulsion requires Httle or no agitation. Microemulsions may become cloudy on beating or cooling, but clarity at intermediate temperatures is restored automatically. [Pg.294]

Sverdlow, N, and Buchta, M.A., Practical solution of induction heating problems resulting from high current buses , Trans. IEEE, 78, 1736-1742 (1959). [Pg.950]

The contact between the aluminium layers and the ceramic substrate requires a joining material which will wet both metal and ceramic, and solders such as the conventional Pb-Sn alloy have been used which are molten during the annealing process. The contact between the solder and the aluminium layer is frequently unsatisfactoty because of the intervention of the AI2O3 layer, and a practical solution appears to be to place drree layers of metal clrromium in contact widr the aluminium, copper in contact with the clrromium, and gold between the copper layer and the solder. [Pg.220]

Every phase of internal coordinate modeling admits many methodological variations, and I do not attempt to review them all. I outline only the standard problems encountered in any particular domain of application and the common practical solutions. [Pg.119]

An important improvement would be the significant reduction of the empty volume in the recycle reactor. This calls for a special insert to block out most of the empty space without choking the flow. A practical solution of this type is on the drawing board. [Pg.154]

The augmentation of power in a gas turbine is achieved by many different techniques. In this section, we are looking at techniques, which could be achieved on existing gas turbines. Thus, techniques such as additional combustors are not considered as being practical on an existing turbine. In other words, the concentration in this section is on practical solutions. Practical power augmentation can be divided into two main... [Pg.95]

Wright, J., A Practical Solution to Transient Torsional Vibration in Synchronous Motor Drive Systems, American Society of Mechanical Engineers, Pub. 75-DE-15. [Pg.633]

A practical solution is to digitize the drawings and place them on CD s available to the maintenance and operation department. A good digital file reduces search time and helps the departments do a better job of keeping the machinery operating at their peak efficiency with minimal downtime. [Pg.743]

Kerr Wilson, W., Practical Solution of Torsional Vibration Problems, Vols. 1 II, London Chapman Hall, Ltd., 1956. [Pg.400]

Current policy in API is to avoid commercial language in the API standard. API standards do not include a guarantee and warranty section. In the revisions, as they occur, other paragraphs deemed commercial are disallowed. This puts the burden of guarantee and warranty verbage on the user. A practical solution, if the user is not familiar with industry practices, is to solicit from the vendor a proposed guarantee that should be a zero tolerance on head and capacity. This would only be good prac-... [Pg.454]

Residual stresses occur from welding and other fabrication techniques even at very low stress values. Unfortunately, stress relief of equipment is not usually a reliable or practical solution. Careful design of equipment can eliminate crevices or splash zones in which chlorides can concentrate. The use of high-nickel stainless steel alloy 825 (40% nickel, 21% chromium, 3% molybdenum and 2% copper) or the ferritic/austenitic steels would solve this problem. [Pg.73]

In determining tlie aspect ratio requhed when SUF = SUFy (altliough it may not be a practical solution), substitute SUFy for SUF on the left side of Equation 13-27 ... [Pg.1052]

Deuterium labeling of certain positions in the steroid nucleus can be a serious problem if suitably functionalized starting materials are not available or if a particular part of the molecule to be labeled is unsuitable for the various reactions described previously in this chapter. In these cases, the only practical solution to this problem is to incorporate the appropriately labeled carbon fragment by synthesis of the desired skeleton. [Pg.208]

For this case it is impractical to lower the dew point with methanol. A more practical solution would be to separate the condensate first. At 1,000 psia the dew point is 68.4°F (see example in Chapter 5). Assuming a separator temperature of 75°F the amount of methanol needed to lower the dew point of gas to 65°F is 9.7 Ib/MMscf. Using a surge factor of 1.4, the required injection rate is only 13.6 Ib/MMscf or 2.0 gal/MMscf. [Pg.107]

Provides a coordinated crop protection industry response to the development of resistance in insect and mite pests. During the last decade, IRAC has formed several international working gi oups to provide practical solutions to mite and insect resistance problems within major crops and pesticide groups. [Pg.271]

A more practical solution to this problem was reported by Larson, in which the amide substrate 20 was treated with oxalyl chloride to afford a 2-chlorooxazolidine-4,5-dione 23. Reaction of this substrate with FeCL affords a reactive A-acyl iminium ion intermediate 24, which undergoes an intramolecular electrophilic aromatic substitution reaction to provide 25. Deprotection of 25 with acidic methanol affords the desired dihydroisoquinoline products 22. This strategy avoids the problematic nitrilium ion intermediate, and provides generally good yields of 3-aryl dihydroisoquinolines. [Pg.379]

In the case of 3b, Gaussian quadrature can be used, choosing the weighting function to remove the singularities from the desired integral. A variable step size differential equation integration routine [38, Chapter 15] produces the only practicable solution to 3c. [Pg.81]

Arps, J. J., and J. L. Arps, The subsurface telemetry problem A practical solution, yourna/ of Petroleum Engineering, May 1964. [Pg.1378]

Does this model give us a practical solution for the synthesis of monosubstitution products in high yields The model teaches us that reactions are not disguised by micromixing if the intrinsic rate constant (in Scheme 12-84 k2o and k2v>) is significantly less than 1 m-1s-1. As discussed in Section 12.7, the intrinsic rate constant refers to unit concentrations of the acid-base equilibrium species involved in the substitution proper, not to analytical concentrations. Therefore, if the azo coupling reaction mentioned above is not carried out within the range of maximal measured rates (i.e., with the equilibria not on the side of the 1-naphthoxide ion and... [Pg.374]

The difference in sulfonation behavior between a-olefins (AO) and internal olefins (IO) has been a longstanding problem [14] and the literature is replete with earlier explanations [14,15] and practical solutions [16-20] to the problem of IO sulfonation. In their studies of IO sulfonation chemistry, Stapersma and colleagues [4], Radici et al. [21], Yoshimura et al. [22,23], and Roberts and Jackson [24] identified the origins of the poor sulfonatability of IO, and the process modifications required to produce good-quality IO sulfonate. [Pg.367]

Unfortunately, this procedure can only be successful if the critical pair can be well resolved and column overload is a practical solution to the problem. Often, due to the complex nature of practical mixtures, values for these conditions are not realized and the optimum column... [Pg.120]

Good at pulling out learning. Like practical solutions support... [Pg.175]

Laboratory. This will eventually come about because this is the practical solution to the sampling of minute specimens. The micromanipulator, may be adapted to a sampler-diluter where amounts of the order of a few nanoliters are being sampled followed through the same tip by a diluting solution of several microliters. [Pg.105]


See other pages where Practical Solutions is mentioned: [Pg.743]    [Pg.92]    [Pg.2]    [Pg.520]    [Pg.121]    [Pg.289]    [Pg.291]    [Pg.290]    [Pg.299]    [Pg.361]    [Pg.79]    [Pg.96]    [Pg.105]    [Pg.40]    [Pg.902]    [Pg.1223]    [Pg.117]    [Pg.75]    [Pg.76]    [Pg.54]    [Pg.327]   


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