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Numerical Applications

An elliptic-based cylindrical apparatus (D = 1 m, H = 1 m) contains a solution stirred with a 6-paddled stirrer (d = 0.4 m and b = 0.1 m). The stirrer is placed in the tank in such a position as to get the ratio h/H = 0.2 (see Fig. 4.1) and to work at n= 0.1, 0.3, 0.5, 0.7, 0.9, 1.1, 1.3, 1.5 revolutions/s. A compound with the same physical properties as the solution is fed close to the liquid surface. The obtained mixture is flushed out through a pipe placed near the base of the apparatus. The entry and the exit flows are identical (Q = 0.0048 m /s). Now the question is to obtain the dependences of the parameters characterizing this mixing case according to the number of revolutions of the stirrer. [Pg.198]

Before developing the algorithm of calculation, we have to deduce the mixture h/H [Pg.198]

According to Eqs. (4.11) and (4.12) and in agreement with Fig. 4.2 we can conclude that among the 49 probabilities only the following ones are not null  [Pg.199]

With these probabilities, the passing matrix can be written. For brevity, we use the [Pg.199]

The numerical text of the calculation, shown in Fig. 4.3, leads to the program given in Fig. 4.4 and has the graphic interface (Fig. 4.5) associated with this program. A description of the graphic interface is given below  [Pg.200]


Note that in liquid phase chromatography there are no detectors that are both sensitive and universal, that is, which respond linearly to solute concentration regardless of its chemical nature. In fact, the refractometer detects all solutes but it is not very sensitive its response depends evidently on the difference in refractive indices between solvent and solute whereas absorption and UV fluorescence methods respond only to aromatics, an advantage in numerous applications. Unfortunately, their coefficient of response (in ultraviolet, absorptivity is the term used) is highly variable among individual components. [Pg.27]

Petroleum solvents are relatively light petroleum cuts, in the C4 to C14 range, and have numerous applications in industry and agriculture. Their use is often related to their tendency to evaporate consequently, they are classified as a function of their boiling points. [Pg.271]

This book presents a detailed exposition of angular momentum theory in quantum mechanics, with numerous applications and problems in chemical physics. Of particular relevance to the present section is an elegant and clear discussion of molecular wavefiinctions and the detennination of populations and moments of the rotational state distributions from polarized laser fluorescence excitation experiments. [Pg.2089]

Multi-necked flasks. Fig. II, 1, 8, a, illustrates a typical threenecked flask. This has numerous applications in organic chemistry for many operations, the central aperture carries a mechanical stirrer, and the two side apertures a dropping funnel and a reflux condenser respectively. [Pg.51]

Numerous applications have been reported. A derivative of the (alkyn-1-yl)nucleosides 295. which have anticancer and antiviral activities, has been synthesized by this reaction. They are also used as chain-terminating nucleosides for DN.A. sequencing[l98,199]. In this reaction, use of DMF as the solvent is most important for successful operation[200]. Only the alkenyl bromide moiety in 2-bromo-3-aceto.xycycloheptene (296) reacts with alkynes without attacking the allylic acetate moiety[201]. [Pg.169]

The intramolecular allylation of soft carbon nucleophiles with allylic acetates as a good cyclization method has been extensively applied to syntheses of various three, four, five and six-membered rings, and medium and macrocyclic compounds[44]. Only a few typical examples of the cyclizations are treated among numerous applications. [Pg.299]

The structural types described m this section are but a tiny fraction of those pos sible The chemistry of heterocyclic aromatic compounds is a nch and varied held with numerous applications... [Pg.461]

Flow injection analysis has also found numerous applications in the analysis of clinical samples, using both enzymatic and nonenzymatic methods. A list of selected examples is given in Table 13.3. [Pg.656]

From the beginning of this century, the demand for asbestos fibers grew in a spectacular fashion for numerous applications, in particular for thermal insulation in steam engines and technologies (4). Moreover, the development of the Hatschek machine in 1900 for the continuous fabrication of sheets from an asbestos—cement composite opened an important field of industrial application for asbestos fibers. [Pg.344]

Oxazoles are also obtained by the reaction of a-halogenoketones (78) with primary amides (the Bliimlein-Lewy synthesis), and this method is particularly appropriate for oxazoles containing one or more aryl groups as in (79). Formamide may also be used in this process, resulting in a free 2-position in the oxazole, and when a urea derivative (80) is used, 2-aminooxazoles (81) are formed (80ZOR2185, 78IJC(B)1030, 78JIC264). Numerous applications of these procedures are described in Chapter 4.18. [Pg.119]

Numerous applications where the recovery of power is important are being explored and exploited to an increasing degree. These are classified as turboexpander applications because of the importance of reliability and high efficiency. Turboexpanders meet these requirements and are available in the needed capacity ranges. A 5,000 hp (3,727 kW) compressor-loaded turboexpander is shown in Figure 2-10. [Pg.31]

In numerous applications of polymeric materials multilayers of films are used. This practice is found in microelectronic, aeronautical, and biomedical applications to name a few. Developing good adhesion between these layers requires interdiffusion of the molecules at the interfaces between the layers over size scales comparable to the molecular diameter (tens of nm). In addition, these interfaces are buried within the specimen. Aside from this practical aspect, interdififlision over short distances holds the key for critically evaluating current theories of polymer difllision. Theories of polymer interdiffusion predict specific shapes for the concentration profile of segments across the interface as a function of time. Interdiffiision studies on bilayered specimen comprised of a layer of polystyrene (PS) on a layer of perdeuterated (PS) d-PS, can be used as a model system that will capture the fundamental physics of the problem. Initially, the bilayer will have a sharp interface, which upon annealing will broaden with time. [Pg.667]

There are numerous applications in solvent recovery processes where evaporation equipment are employed. Figure 14 provides an example of a process scheme for toluene-di-isocyanate recovery. This is an example of continuous vacuum evaporation of distillation residues. [Pg.108]

Claybrook, S 1992, Comparison of FTRIN Predictions to 1986 LLNL Enclosure Fire Tests 9 and 10, Numerical Applications Inc, Personal Communications. [Pg.475]

Electrostatic precipitation is one of the fundamental means of separating solid or liquid particles from gas streams. This technique has been utilized in numerous applications, including industrial gas-cleaning systems, air cleaning in general ventilation systems, and household room air cleaners. [Pg.1211]

Numerous application examples are related to gel filtration (e.g., see Hagel, 1989 Hagel and Janson, 1992 Pharmacia, 1991). A selected number of applications are discussed with respect to their goals and to types of methods and SEC media attributes, which impact the selection and or construction of a suitable SEC column. Specific examples of these various applications types are given later under Sections II,C and III. The optimization of running conditions to achieve the desired results are discussed in Section VI. [Pg.29]

Chiral oxazolines developed by Albert I. Meyers and coworkers have been employed as activating groups and/or chiral auxiliaries in nucleophilic addition and substitution reactions that lead to the asymmetric construction of carbon-carbon bonds. For example, metalation of chiral oxazoline 1 followed by alkylation and hydrolysis affords enantioenriched carboxylic acid 2. Enantioenriched dihydronaphthalenes are produced via addition of alkyllithium reagents to 1-naphthyloxazoline 3 followed by alkylation of the resulting anion with an alkyl halide to give 4, which is subjected to reductive cleavage of the oxazoline moiety to yield aldehyde 5. Chiral oxazolines have also found numerous applications as ligands in asymmetric catalysis these applications have been recently reviewed, and are not discussed in this chapter. ... [Pg.237]

Considering the numerous applications, heart-cut LC-LC has convincingly proven its value. Nevertheless, in LC-LC specific method development is generally needed for each analyte. Moreover, heart-cut procedures require accurate timing and, therefore, the performance of the first analytical column in particular should be highly stable to thus yield reproducible retention times. This often means that in LC-LC some kind of sample preparation remains necessary (see Table 11.1) in order to protect the first column from proteins and particulate matter, and to guarantee its lifetime. [Pg.265]

In order to reduce or eliminate off-line sample preparation, multidimensional chromatographic techniques have been employed in these difficult analyses. LC-GC has been employed in numerous applications that involve the analysis of poisonous compounds or metabolites from biological matrices such as fats and tissues, while GC-GC has been employed for complex samples, such as arson propellants and for samples in which special selectivity, such as chiral recognition, is required. Other techniques include on-line sample preparation methods, such as supercritical fluid extraction (SFE)-GC and LC-GC-GC. In many of these applications, the chromatographic method is coupled to mass spectrometry or another spectrometiic detector for final confirmation of the analyte identity, as required by many courts of law. [Pg.407]

Compute the tool face orientation. In the numerical application above, is the borehole going to turn right, left or go straight if we keep on drilling with this orientation ... [Pg.919]

Alloys with rhodium Rhodium alloys readily with platinum in all proportions, although the workability of the resulting alloy decreases rapidly with increasing rhodium content. Alloys containing up to about 40% rhodium, however, are workable and find numerous applications. The principal physical and mechanical properties of rhodium-platinum alloys are listed in Table 6.3. [Pg.925]

The excellent resistance of platinum, rhodium and iridium to oxidation at high temperatures finds numerous applications in technology, in particular in the form of platinum-based alloys. Osmium and ruthenium form volatile oxides which may be isolated (OSO4 and RujOj), and they are not widely used. [Pg.933]

Natural product total syntheses are particularly valuable when they are attended by the development of general utility methods of synthesis. In some instances, the successful completion of a natural product total synthesis requires the development and application of a new synthetic method. The total synthesis of erythronolide B by Corey et al. is one of these instances. The double activation macro-lactonization method was a fruitful innovation that was introduced in response to the challenge presented by the macrocyclic structures of the erythromycins. Several other methods to achieve the same objective, and numerous applications followed. [Pg.183]

Numerous applications of the Ni(n)/Cr(ii)-mediated coupling reaction in total synthesis have already been reported.11 Some of the more noteworthy examples derive from Kishi s laboratories and played a role in the syntheses of such complex molecules as (+)-ophiobolin C16 and halichondrin B17 (see Scheme 5). Another elegant application can be found in the enantioselective total syntheses of (+)-brefeldin C and 4-ep/-brefeldin C by Schreiber and Meyers (see Scheme 5).18... [Pg.717]

Because of the success of the r12 method in the applications, one had almost universally in the literature adopted the idea of the necessity of introducing the interelectronic distances r j explicitly in the total wave function (see, e.g., Coulson 1938). It was there-fore essential for the development that Slater,39 Boys, and some other authors at about 1950 started emphasizing the fact that a wave function of any desired accuracy could be obtained by superposition of configurations, i.e., by summing a series of Slater determinants (Eq. 11.38) built up from a complete basic one-electron set. Numerical applications on atoms and molecules were started by means of the new modern electronic computers, and the results have been very encouraging. It is true that a wave function delivered by the machine may be the sum of a very large number of determinants, but the result may afterwards be mathematically simplified and physically interpreted by means of natural orbitals.22,17... [Pg.257]

Numerous applications of polymer-coated silicas to chromatography of biopolymers allow one to conclude that adsorbed or grafted hydrophilic nonionizing... [Pg.136]

An important example in this context is the hydrosilation reaction [121]. Hydrosilation is the formal addition of a silane to an alkene in presence of a hydrosilation catalyst. This reaction has numerous applications e.g., with a suitable catalyst, an enantioselective hydrosilation is possible [122] and also hydrosilation and double hydrosilation of alkines [123] are known. [Pg.14]

In the reference cited in footnote 18, very long calculations are made by which all functions (%, 2, , A1,A2, , BlsB2, > ) are determined, and applications are developed from the general formulas so established. There are numerous applications indicated in the text illustrating the operation of this method. [Pg.362]


See other pages where Numerical Applications is mentioned: [Pg.2316]    [Pg.387]    [Pg.111]    [Pg.316]    [Pg.515]    [Pg.228]    [Pg.161]    [Pg.12]    [Pg.704]    [Pg.113]    [Pg.13]    [Pg.247]    [Pg.111]    [Pg.110]    [Pg.386]    [Pg.145]    [Pg.62]    [Pg.253]    [Pg.919]    [Pg.39]    [Pg.5]    [Pg.319]   
See also in sourсe #XX -- [ Pg.144 ]




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