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Heterogeneous applications

Homogeneous catalysis and heterogenized applications of homogeneous catalysis... [Pg.121]

Heterogeneous catalysts were first reported by Eleuterio [3] and the reaction concerned metathesis of light olefins over M0O3 on alumina at high temperature, 160 °C. Heterogeneous applications involve the conversion of... [Pg.337]

Above we have mentioned several heterogeneous applications such as the OCT process and SHOP. Neohexene (3,3-dimethyl-1-butene), an important intermediate in the synthesis of fine chemicals, is produced from the dimer of isobutene, which consists of a mixture of 2,4,4-trimethyl-2-pentene and 2,4,4-trimethyl- 1-pentene. Cross-metathesis of the former with ethene yields the desired product. The catalyst is a mixture of W03/Si02 for metathesis and MgO for isomerisation at 370 °C and 30 bar. The isobutene is recycled to the isobutene dimerisation unit [48],... [Pg.354]

Abstract. Service-oriented architectures define an architectural style for the construction of a heterogeneous application landscape. By abstracting services, business processes are decoupled from the underlying applications. This section describes how the results of the IMPROVE subproject 13, related to the model-driven development process for wrapper construction, are transferred and extended to the area of business process applications. We present an approach which yields a prototype to formally specify service descriptions and service compositions. This prototype makes it possible to evaluate and explore service-oriented architecture concepts. [Pg.727]

Lyon, G., B. Hagberg, P. Evrard, C. Allaire, L. Pavone, and V. M. 1991. Symptomatology of late onset Krabbe s leukodystrophy The European experience. Dev Neurosci 13 240-244. Maestri, N. E., and T. H. Beaty. 1992. Predictions of a 2-locus model for disease heterogeneity Application to adrenoleukodystrophy. Am J Hum Genet 44 576-582. [Pg.316]

Dantu, P. (1958) Etude des contraintes dans le milieux heterogenes. Applications au beton , Annales de ITTBTP, 11(121) 55-67. [Pg.248]

It should be noted that most of the reactions highlighted in this chapter are from the last few years, considering the wealth of reviews on this subject that have appeared over the last lOyears [Ij. Also, owing to the novelty of this particular field, heterogeneous applications and other type developments appear to be quite few, well, for the moment anyway. ... [Pg.176]

Another direction has been to develop heterogeneous applications of diruthenium paddlewheels [97]. By using multitopic carboxylate ligands, for example, 1,4-benzenedicarboxyate, RUj tetracar-boxylates are assembled into microporous networks. Interesting applications such as the catalytic hydrogenation of alkenes, the oxidation of primary aliphatic alcohols, and photocatalytic hydrogen production from water have been reported [98-101]. [Pg.242]

The ARINC-653 architecture [1] is built upon the concept of partition, a kind of container for applications whose execution is both spatially and temporally isolated. Partitioning eases the verification, validation and certification of heterogeneous applications executed in the same hardware platform [20], which may feature different levels of criticality and/or may even be developed by different companies. [Pg.221]

Figure 1 shows two spectra from two sections of a modern painting. The damage to the picture might have been caused by a heterogeneous application of oil or the poor conservation of the picture. A non-homogeneous distribution of oil over the surface was made evident when two sections of the picture were analysed. As it was possible to use part of the picture from under the frame, the amount of sample was sufficient to allow use of the attenuated total reflectance horizontal accessory. [Pg.605]

The Systems Biology Workbench (SBW) (SBW Bergmann and Sauro 2006) is a software framework that allows heterogeneous applications, written in different programming languages and running on different platforms to communicate via a simple network protocol. [Pg.347]

Although Gibbs published his monumental treatise on heterogeneous equilibrium in 187S, his work was not generally appreciated until the turn of the century, and it was not until many years later that the field of surface chemistry developed to the point that experimental applications of the Gibbs equation became important. [Pg.79]

The importance of the solid-liquid interface in a host of applications has led to extensive study over the past 50 years. Certainly, the study of the solid-liquid interface is no easier than that of the solid-gas interface, and all the complexities noted in Section VIM are present. The surface structural and spectroscopic techniques presented in Chapter VIII are not generally applicable to liquids (note, however. Ref. 1). There is, perforce, some retreat to phenomenology, empirical rules, and semiempirical models. The central importance of the Young equation is evident even in its modification to treat surface heterogeneity or roughness. ... [Pg.347]

This chapter concludes our discussion of applications of surface chemistry with the possible exception of some of the materials on heterogeneous catalysis in Chapter XVIII. The subjects touched on here are a continuation of Chapter IV on surface films on liquid substrates. There has been an explosion of research in this subject area, and, again, we are limited to providing just an overview of the more fundamental topics. [Pg.537]

The analysis is thus relatively exact for heterogeneous surfaces and is especially valuable for analyzing changes in an adsorbent following one or another treatment. An example is shown in Fig. XVII-24 [160]. This type of application has also been made to carbon blacks and silica-alumina catalysts [106a]. House and Jaycock [161] compared the Ross-Olivier [55] and Adamson-Ling... [Pg.658]

While hopes are high, heterogeneous photochemical systems seem not yet to have found major practical application. The photovoltaic cell or solar cell is the only system with important (although specialized) commercial use (see Ref. 343). [Pg.739]

M. Boudart, Supported Metals as Heterogeneous Catalysts, the Science of Precious Metals Applications, International Precious Metals Institute, Allentown, PA, 1989. [Pg.744]

Brey W S 1983 Applications of magnetic resonance in catalytic research Heterogeneous Catalysis Selected American Stories ed B FI Davis and W P Flettinger Jr (Washington American Chemical Society)... [Pg.1799]

The mechanical shaking machine is employed for auto matic mixing of heterogeneous systems and finds many applications in the organic chemistry laboratory. [Pg.69]

It would be difficult to over-estimate the extent to which the BET method has contributed to the development of those branches of physical chemistry such as heterogeneous catalysis, adsorption or particle size estimation, which involve finely divided or porous solids in all of these fields the BET surface area is a household phrase. But it is perhaps the very breadth of its scope which has led to a somewhat uncritical application of the method as a kind of infallible yardstick, and to a lack of appreciation of the nature of its basic assumptions or of the circumstances under which it may, or may not, be expected to yield a reliable result. This is particularly true of those solids which contain very fine pores and give rise to Langmuir-type isotherms, for the BET procedure may then give quite erroneous values for the surface area. If the pores are rather larger—tens to hundreds of Angstroms in width—the pore size distribution may be calculated from the adsorption isotherm of a vapour with the aid of the Kelvin equation, and within recent years a number of detailed procedures for carrying out the calculation have been put forward but all too often the limitations on the validity of the results, and the difficulty of interpretation in terms of the actual solid, tend to be insufficiently stressed or even entirely overlooked. And in the time-honoured method for the estimation of surface area from measurements of adsorption from solution, the complications introduced by... [Pg.292]

G. C. Bond, Heterogeneous Catalysis Principles and Applications, Clarendon Press, Oxford, UK, 1987. [Pg.205]

Diffusion in porous solids is usually the most important factor con-troUing mass transfer in adsorption, ion exchange, drying, heterogeneous catalysis, leaching, and many other applications. Some of the... [Pg.600]

Analysis of such a correlation may reveal the significant variables and interactions, and may suggest some model, say of the L-H type, that could be analyzed in more detail by a regression process. The variables Xi could be various parameters of heterogeneous processes as well as concentrations. An application of this method to isomerization of /i-pentane is given by Kittrel and Erjavec (Ind. Eng. Chem. Proc. Des. Dev., 7,321 [1968]). [Pg.707]

Two complementai y reviews of this subject are by Shah et al. AIChE Journal, 28, 353-379 [1982]) and Deckwer (in de Lasa, ed.. Chemical Reactor Design andTechnology, Martinus Nijhoff, 1985, pp. 411-461). Useful comments are made by Doraiswamy and Sharma (Heterogeneous Reactions, Wiley, 1984). Charpentier (in Gianetto and Silveston, eds.. Multiphase Chemical Reactors, Hemisphere, 1986, pp. 104—151) emphasizes parameters of trickle bed and stirred tank reactors. Recommendations based on the literature are made for several design parameters namely, bubble diameter and velocity of rise, gas holdup, interfacial area, mass-transfer coefficients k a and /cl but not /cg, axial liquid-phase dispersion coefficient, and heat-transfer coefficient to the wall. The effect of vessel diameter on these parameters is insignificant when D > 0.15 m (0.49 ft), except for the dispersion coefficient. Application of these correlations is to (1) chlorination of toluene in the presence of FeCl,3 catalyst, (2) absorption of SO9 in aqueous potassium carbonate with arsenite catalyst, and (3) reaction of butene with sulfuric acid to butanol. [Pg.2115]

Present research is devoted to investigation of application of luminol reactions in heterogeneous systems. Systems of rapid consecutive reactions usable for the determination of biologically active, toxic anions have been studied. Anions were quantitatively converted into chemiluminescing solid or gaseous products detectable on solid / liquid or gas / liquid interface. Methodology developed made it possible to combine concentration of microcomponents with chemiluminescence detection and to achieve high sensitivity of determination. [Pg.88]

The existing models for emitting x-ray fluorescence intensity of elemental analytical lines from heterogeneous samples are limited in practical applications, because in most publications the relations between the fluorescence intensity of analytical lines elements and the properties of powder materials were not completely studied. For example, particles distribution of components within narrow layer of irradiator which emitted x-ray fluorescence intensity of elements might be in disagreement with particles distribution of components within whole sample. [Pg.462]


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See also in sourсe #XX -- [ Pg.7 ]




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