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A brief overview

The formation of a solid product in a reactor is an important complication that may seriously influence the optimum design of the reactor. [Pg.174]

Solid products precipitated from a liquid or gaseous reaction mixture often have the form of fine particles, that have to be separated afterwards. There are many examples of precipitations from solutions, both in organic and inorganic chemistry. Such precipitations are often carried out in stirred reactors. Precipitations from gaseous mixtures are less conunon they may be carried out in tubular reactors or in fluidized bed reactors. [Pg.174]

There are also processes where a solid reaction product is precipitated onto an existing surface. This can be the surface of particles that were already present. [Pg.174]

When solid reaction products are formed from gaseous or liquid reaction mixtures, several phenomena may take place at the same time, such as  [Pg.175]

The final particles may be formed by a combination of these mechanisms. Precipitations from liquids is discussed in section 6.3.2, and from gases in section 6.3.3. [Pg.175]


In the sections below a brief overview of static solvent influences is given in A3.6.2, while in A3.6.3 the focus is on the effect of transport phenomena on reaction rates, i.e. diflfiision control and the influence of friction on intramolecular motion. In A3.6.4 some special topics are addressed that involve the superposition of static and transport contributions as well as some aspects of dynamic solvent effects that seem relevant to understanding the solvent influence on reaction rate coefficients observed in homologous solvent series and compressed solution. More comprehensive accounts of dynamics of condensed-phase reactions can be found in chapter A3.8. chapter A3.13. chapter B3.3. chapter C3.1. chapter C3.2 and chapter C3.5. [Pg.832]

In tills section, we provide a brief overview of some experimental issues relevant m perfomiing surface SHG and SFG measurements. [Pg.1280]

Contains over 40 quick guides that serve as a brief overview of the key information in each chapter... [Pg.492]

Quantitative Structure—Activity Relationships (QSAR). Quantitative Stmcture—Activity Relationships (QSAR) is the name given to a broad spectmm of modeling methods which attempt to relate the biological activities of molecules to specific stmctural features, and do so in a quantitative manner (see Enzyme INHIBITORS). The method has been extensively appHed. The concepts involved in QSAR studies and a brief overview of the methodology and appHcations are given here. [Pg.168]

T. J. McDonough, Kraft Pulp Bleaching Technology A Brief Overview of Basic Principles and Current Trends, Institute of Paper Chemistry, Adanta, Ga., 1992. [Pg.285]

Steroids are nearly ubiquitous to all living organisms and have a variety of structural variations. Herein a brief overview of a few natural steroids from both plant and animal sources that have interesting biological activities or industrial importance is given. [Pg.419]

The purpose of this article is to provide a brief overview of the materials designated synthetic elastomers and the elastomeric or mbbery state. Subsequent entries describe the individual classes of elastomers in detail. Table 1 provides a fundamental description of the principal classes of synthetic elastomers. Table 2 gives the widely accepted ASTM abbreviations for synthetic mbbers. [Pg.465]

A variety of techniques have been introduced to increase the time step in molecular dynamics simulations in an attempt to surmount the strict time step limits in MD simulations so that long time scale simulations can be routinely undertaken. One such technique is to solve the equations of motion in the internal degree of freedom, so that bond stretching and angle bending can be treated as rigid. This technique is discussed in Chapter 6 of this book. Herein, a brief overview is presented of two approaches, constrained dynamics and multiple time step dynamics. [Pg.62]

The properties of electron transfer proteins that are discussed here specifically affect the electron transfer reaction and not the association or binding of the reactants. A brief overview of these properties is given here more detailed discussions may be found elsewhere (e.g.. Ref. 1). The process of electron transfer is a very simple chemical reaction, i.e., the transfer of an electron from the donor redox site to the acceptor redox site. [Pg.393]

The methodological advances just presented have brought the field of nucleic acid force field calculations to a point where results from the calculations can be used with reasonable confidence to aid in the interpretation of experimental data as well as to be used for scientific investigations that are not accessible to experiment. Accordingly, a number of studies based on MD simulations, as well as other methods, have been undertaken to study a wide array of biologically relevant events associated with DNA. A brief overview of some of these efforts follows. [Pg.444]

A brief overview of the form for rate equations reveals that temperature and concentration e Tects are strongly interwoven. This is so even if all four basic steps in the rules of Boudart (1968) are obeyed for the elementary steps. The expectations of simple unchanging temperature effects and strict even-numbered gas concentration dependencies of rate are not justified. [Pg.219]

The advantages of LA are now well-known - no sample preparation is needed, conducting and non-conducting samples of arbitrary structure can be analyzed directly, spatial resolution up to a few microns can be obtained, high vacuum conditions are not required, rapid simultaneous multi-element analysis is possible, and it is possible to obtain complete analytical information with a single laser pulse. A brief overview of the potential and limitations of LA will be given in this chapter. [Pg.231]

The following chart can serve as your road map to the subjects covered in this handbook. The chart provides a brief overview of the subjects covered in each chapter, and will help direct you to specific topical information. Use this along with the subject index to find the information you need. [Pg.48]

AERMOD AERMOD is the next generation air dispersion modeling system and consists of 3 components - AERMOD (air dispersion model), AERMET (meteorological data preprocessor) and AERMAP (terrain preprocessor). A brief overview of the model can be found in the mod-desc.txt file which can be downloaded from the site. [Pg.330]

This chapter has only provided a brief overview of the technology of distillation. In part, to highlight some important engineering concepts and equipment, the following summary is given. As described, refinery main fractionators are distillation towers that separate very wide boiling fractions into a series of rough... [Pg.241]

Because the WAO process also aims to reduce sludge volume we will spend more time describing this process under the section dealing with Volume Reduction. The other thermal sludge conditioning method is best-known as sludge pasteurization, and deserves more than just a brief overview. [Pg.514]

An important element of pollution prevention is the selection of environmentally benign chemical reactions, raw materials, solvents, and products. Over the past few years, significant progress has been made in this area. This chapter provides a brief overview of the recent advances in synthesizing green reactions and species. For more detailed discussion, the reader is referred to Anastas and lliamson (1996), Anastas and Farris (1994), and Chase (1995). [Pg.289]

Heat exchangers used in gas production facilities are shell-and-tube, double-pipe, plate-and-frame, bath-type, forced-air, or direct-fired. In this chapter we will discuss the basic concepts for sizing and selecting heat exchangers. This is just a brief overview of this complex subject and is meant to provide the reader with a basis upon which to discuss specific sizing and selection details with heat exchange experts in engineering companies and with vendors. [Pg.47]

When the underlying distribution is not known, tools such as histograms, probability curves, piecewise polynomial approximations, and general techniques are available to fit distributions to data. It may be necessary to assume an appropriate distribution in order to obtain the relevant parameters. Any assumptions made should be supported by manufacturer s data or data from the literature on similar items working in similar environments. Experience indicates that some probability distributions are more appropriate in certain situations than others. What follows is a brief overview on their applications in different environments. A more rigorous discussion of the statistics involved is provided in the CPQRA Guidelines. ... [Pg.230]

Synthetic organic chemical production is approximately 200 billion pounds per year. " There are more than 8 million known organic compounds, and of these, the compounds that are commercially produced are too numerous to mention. Only a brief overview of commercially produced syntlietic organic chemicals can be given here. [Pg.281]

The theory for a one-degree-of-freedom system is useful for determining resonant or natural frequencies that occur in all machine-trains and process systems. However, few machines have only one degree of freedom. Practically, most machines will have two or more degrees of freedom. This section provides a brief overview of the theories associated with two degrees of freedom. An undamped two-degree-of-freedom system is illustrated in Figure 43.16. [Pg.682]

Assuming that the motion in the phase space is bounded, we know that volumes cannot, on average, expand he., that A 0. On the other hand, the set of possible behaviors of systems for which A < 0 is different from those for which A = 0. A brief overview of each of these two fundamental types of dynamical systems is given in the remaining paragraphs of this section more detailed discussions, with examples, follow in sections 4.1.1 and 4.1.2. [Pg.169]

We begin our discussion of LG computers by considering some of the generic advantages and disadvantages of using LGs to simulate fluid dynamics. Later on ill this section we will provide a brief overview of some of the more popular LG computers that are now in use. [Pg.503]

The chapter is organized as follows in Section 8.2 a brief overview of ultrafast optical dynamics in polymers is given in Section 8.3 we present m-LPPP and give a summary of optical properties in Section 8.4 the laser source and the measuring techniques are described in Section 8.5 we discuss the fundamental photoexcitations of m-LPPP Section 8.6 is dedicated to radiative recombination under several excitation conditions and describes in some detail amplified spontaneous emission (ASE) Section 8.7 discusses the charge generation process and the photoexcitation dynamics in the presence of an external electric field conclusions are reported in the last section. [Pg.445]

This section gives a brief overview of the structure of nickel hydroxide battery electrodes and a more detailed review of the solid-state chemistry and electrochemistry of the electrode materials. Emphasis is on work done since 1989. [Pg.136]

Simpson ER, Clyne C, Rubin G et al (2002) Aromatase -A Brief Overview. Annu Rev Physiol 54 93-127... [Pg.221]

Radicals arc chemical species that possess an unpaired electron sometimes called a free spin. The adjective free , often used to designate radicals, relates to the state of the impaired electron it is not intended to indicate whether the compound bearing the free spin is complcxcd or uncomplexcd. in this section wc provide a brief overview of the structure, energetics and detection of radicals. [Pg.12]

The composition of body fluids remains relatively constant despite the many demands placed on the body each day. On occasion, these demands cannot be met, and electrolytes and fluids must be given in an attempt to restore equilibrium. The solutions used in the management of body fluids discussed in this chapter include blood plasma, plasma protein fractions, protein substrates, energy substrates, plasma proteins, electrolytes, and miscellaneous replacement fluids. Electrolytes are electrically charged particles (ions) that are essential for normal cell function and are involved in various metabolic activities. This chapter discusses the use of electrolytes to replace one or more electrolytes that may be lost by the body. The last section of this chapter gives a brief overview of total parenteral nutrition (TPN). [Pg.633]

Both pyrochemical and aqueous methods are used at Rocky Flats to process plutonium metal scrap, oxide, and other residues. The pyrochemical processes currently in production include electrorefining, fluorination, hydriding, molten salt extraction, calcination, and reduction operations. Aqueous processing and waste treatment methods involve nitric acid dissolution, ion exchange, solvent extraction, and precipitation techniques. A brief overview of the chemistry involved in these operations is described. Research to improve these operations, or develop new processes, is also presented. [Pg.365]

In this chapter a brief overview is given of the usual sulfonation methods. A detailed description can be found in the book by Moretti and the literature cited therein. [Pg.79]

The information presented in this chapter is intended to provide a brief overview of the composition, performance, and formulation properties of LAS by itself and in combination with other surfactants. The particular performance synergies and processing characteristics of certain combinations of surfactants are discussed briefly. The examples of mixed active formulations provided herein represent to the best of the author s knowledge the approximate levels of major surfactants in actual household detergent products both past and present. This does not imply that these formulations are complete because many additives, such as bleaches, enzymes, builders, hydrotropes, thickeners, perfumes, and coloring agents, may also be present in varying amounts. [Pg.110]

The literature in this field is confusing because of a somewhat haphazard method of nomenclature that has arisen historically. This is compounded by some mistakes in structure determination, reported in early papers, and which are occasionally quoted. The first part of this chapter deals with nomenclature and with a brief overview of early work. Subsequent sections deal with the formation and metabolism of di-D-fructose dianhydrides by micro-organisms, and the formation of dihexulose dianhydrides by protonic and thermal activation. In relation to the latter topic, recent conclusions regarding the nature of sucrose caramels are covered. Other sections deal with the effects of di-D-fructose dianhydrides upon the industrial production of sucrose and fructose, and the possible ways in which these compounds might be exploited. An overview of the topic of conformational energies and implications for product distributions is also presented. [Pg.208]

Before discussing the medium engineering phenomenon and its synthetic relevance in details, it is useful to offer a brief overview of the fundamentals of biocatalysis in organic media. [Pg.8]

In the following text, a brief overview of functionalization of various olefins is provided to give an outline of the current synthetic potential of this biooxygenation. [Pg.241]


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