Theoretical considerations, industrial

Hixson, A. and Crowell, J., Dependence of reaction velocity upon surface and agitation. I. Theoretical considerations, Industrial and Engineering Chemistry Research, Vol. 51, 1931, pp. 923-931. 

In this section we examine some examples of cross-linked step-growth polymers. The systems we shall describe are thermosetting polymers of considerable industrial importance. The chemistry of these polymerization reactions is more complex than the hypothetical AB reactions of our models. We choose to describe these commercial polymers rather than model systems which might conform better to the theoretical developments of the last section both because of the importance of these materials and because the theoretical concepts provide a framework for understanding more complex systems, even if they are not quantitatively successful. 

In addition to general scientific meetings which contain papers involving LC-MS, the Annual Montreux Meeting, held since 1980, is a meeting devoted to LC-MS, CE-MS and MS-MS which deals with technical developments in on-line aspects, theoretical considerations, and applications of the techniques in enviromnental, clinical, industrial and pharmaceutical analysis, and other fields. Recent advances... 

The bipyridines, of considerable industrial and theoretical interest, are comprehensively reviewed for the first time by Summers. 

The salt effect of single or mixed electrolytes on the solubility of a gas in water is of considerable industrial and theoretical interest. Methods to predict or correlate these effects have been presented by various workers and have been reviewed briefly (I). With the exception of a study by Clever and Reddy (2), previous investigations found no salt effect data on gas solubility in non-aqueous or mixed solvents. Clever and Reddy (2) observed the solubilities of helium and argon in methanol solutions of sodium iodide at 30° C and showed that the following Setschenow equation is not always applicable to such a system. 

Much equipment for the separation of liquids and finely divided solids was invented independently in a number of industries and is of diverse character. These developments have occurred without benefit of any but the most general theoretical considerations. Even at present, the selection of equipment for specific solid-liquid separation applications is largely a process of scale-up based on direct experimentation with the process material. 

North American Refractories Company, Refractories for the Glass Industry Properties, Theoretical Considerations, and Recommendations. NARCO, Cleveland, OH. 

The intent of this chapter is to present a brief review of simple, fundamental physicochemical principles and experimental results which are necessary to understand both the mechanism of adsorption of ionic surfactants from aqueous solutions on oxide surfaces and the action of some simple, fundamental applications. It does not enter into details in the theoretical consideration, nor does it attempt to explain complex industrial uses. Both problems have been thoroughly treated in several review articles and monographs [e.g., 1-10]. Here emphasis is placed on the contribution the adsorption calorimetry makes to the improvement of current understanding of the interactions of ionic surfactants at the mineral-water interface. All experimental data, used for the illustrative purposes throughout this chapter, were obtained at the Laboratoire des Agregats Moleculaire et Materiaux Inorganiques. 

Both the published literature and previously unpublished information obtained by the structural panel industry indicate that formaldehyde levels associated with panel products glued with phenol formaldehyde adhesives are extremely low. Large dynamic chamber tests which simulate conditions that might be found in tightly sealed residences indicate consistently that formaldehyde levels associated with freshly manufactured phenolic panel products are less than 0.1 parts per million. The data, as well as theoretical considerations, also indicate that the amount of formaldehyde contributed to the environment by phenolic panel products should rapidly approach zero as the small quantity of formaldehyde initially present in the products is released. 

It is the intention of this review to give the professional in the food industry an overview of the types of analyses currently possible using CE. While an overview of modes of separation will be introduced, it is not the intent of this review to go into the detail of theoretical considerations important to having a dynamic understanding of CE as a separation technique. Instead, the reader is referred to references which go into detail on these issues [5-8]. It is also not the intent of this review to give an exhaustive review of the hterature for CE. For information on the use of CE in bioanalysis, the reader is referred to Landers, et al. [9] and Mazzio and KruU [10]. For a comprehensive review of CE, the reader is referred to the review by Ruhr and Monnig [11]. Finally, Zeece has reviewed CE as a tool specifically for food science [12]. 

The second line of thought behind this book was that we wanted a monograph that can be used by graduate students and industry-based technical and operations staff ahke. To achieve this goal we chose the following general layout Brief theoretical considerations, mode of operations, specific... 

The great majority of catalytic reactions which have been applied technically as industrial processes are those where solid catalytic material acts on gaseous material. They, therefore, represent one type of hetcro-qeneous catalvsis. In such cases, theoretical considerations, especially those based upon the laws of mass action, do not apply in the same way as in cases where the system is homogeneous, i.e. where the catalyst together with all of the components of the reaction are in the same state of aggregation as, for example, when all are either liquids or gases. 

The kinetics of coke bum-off were determined by systematic experiments in different lab-scale reactors. The experiments and theoretical considerations clearly indicate that for carbon loads of 10 gc/lOOgcat and temperatures above 400°C the effective rate of carbon bum-off is strongly influenced by pore diffusion. The external gas-solid mass transfer can be neglected for temperatures below 800 C, i. e. for temperatures of industrial relevance (T<550°C ). Based on the experimental results, the technical process of the regeneration was modeled. 

Before we move on to comment and discuss these questions, we account for some theoretical considerations on the existence and derivation of a gap between actual practices and written procedures, i.e. preferred work practice. As observe that deviating work practices are a well-known phenomenon in many sectors and industries, and thus a recurring theme in organizational and safety studies. 

Latex la- teks [NS latic. latex, from L. fluid] (1835) (pi lattices or latexes) n. (1) An emulsion of a polymeric substance in an aqueous medium. (2) The sap of the hevea (rubber) tree and other plants, or emulsions prepared from the same. Latices of interest to the coatings and plastics industry are based mainly on styrene-butadiene co-polymers, polystyrene, acrylics, and vinyl polymers and co-polymers. (3) Fine dispersion of rubber or resin, natural or synthetic, in water the synthetic is made by emulsion polymerization. Latex and emulsion are often used synonymously in the paint industry. Emulsified monomers once polymerized become solids or plasticized gel particles and not emulsions but aqueous suspensions. Lovell PA, El-Aasser MS (eds) (1997) Emulsion polymerization and emulsion polymers. John Wiley and Sons, New York. Martens CR (1964) Emulsion and water-soluble paints and coatings. Reinhold Publishing Co., New York. VanderhofF JW, Gurnee EE (1956) Motion picture investigation of polymer latex phenomena. TAPPI 39 (2) 71-77. VanderhofF JW, Tarkowski HL, Jenkins MC, Bradford EG (1966) Theoretical considerations of the interfacial forces involved in the coalescence of latex particles. J Macromol Chem 1 (2) 361-397. 

Suspensions are defined as the stable dispersions of fine solid particles in liquids. Due to the widespread use of suspensions in industry, accurate analysis of their fluid dynamical behavior is needed to carry out the design calculations in many flow processes. According to the theoretical considerations the fluid dynamical behavior of a suspension may depend on a very large number of factors. In this respect, material characteristics of liquids and solids in the dispersion and the composition of the mixture in terms of solid volume fraction, particle size distribution, and interactions between solid particles can be mentioned. 

Theoretical considerations show that a cooling step is not required (see Section 9.6) but such a step is in fact included in many industrial units. 

A section is dedicated to the interpretation of granulation experiments performed at different scales and how these can be used in scale-up of the process from laboratory and pilot size to full-scale industrial equipment. It is only very recently that criteria for such scale-up have become available mainly from theoretical considerations of granule growth and breakup at the micro-scale, and this new knowledge is briefly presented. Finally, some recent computations are presented in which the process of both agglomeration and... 

Up to 1995, the year in which he became Professor emeritus, and even thereafter he was active in different fields of solid state electrochemistry (solid electrolytes, sensors, SOFC). His pioneering work encompasses contributions to solid oxide fuel cells, theoretical considerations regarding electrochemical phenomena in solid electrolyte cells, basic discoveries in solid electrolyte gas cells, and their applications as gas sensors in different branches of industry. Without any doubt, the discovery of the fuel-oxygen titration curve by means of solid electrolyte cells on which the lambda probe is based is his most memorable contribution to electrochemistry. At the Second European Solid Oxide Fuel Cell Forum, which took place in Oslo on May 1996, Prof. Dr. Hans-Heinrich Mobius was awarded the Christian Friedrich Schonbein Medal of Honor in recognition of his outstanding contributions to the fundamentals and the technology of solid electrolyte fuel cells [1]. 

Emulsion polymerization of unsaturated monomers where the monomer and polymer are mutually insoluble, are of considerable industrial importance, but there is no generally accepted theoretical framework to discuss them. A major problem in the mechanistic investigation of any multiple - phase polymerization system is the number and complexity of the reactions which must be taken into account. For example, in such particles the formation of reaction loci and the growth of polymer chains occur simultaneously and each of these processes is itself complex. In quantifying the kinetics of heterogeneous polymerizations, where monomer and polymer are mutually immissible (insoluble), it is essential to take proper account of the compartmentalized nature of the system. 

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