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A Few Important Results

We see from this short account that measurements of free diffusion, with the present state of experimental technique, are able to afford a very good picture of the behavior of large molecules in solution the investigations on high polymeric substances will be described with all details in [Pg.300]

Lehner and J, E. Smith, Colloid Symposium Monograph 13,65 (1935) Dyestuff II is p-sulfobenzazobenzazo-6-benzoyl-p-aminobenzoyl-amino-naphthol-3-sodium sulphonate. [Pg.301]

Substance Method Applied Molecular Weight (Particle Weight) Remark Refer- ence [Pg.302]

Regenerated cellu- ti 90,000-110,000 enough calculated for (C6Hio06)x In Cuoxam sol. calcu- 1 [Pg.302]

Cellulose acetate equilibrium Free diffusion 10,000-50,000 In acetone calculated H [Pg.302]


It should be emphasized that a plethora of research papers and patents have been devoted to the field of photoreactions in synthetic polymers. However, only a few important results are highlighted in this chapter. For more detailed information, the reader is referred to relevant books and reviews [1-28]. [Pg.178]

The different approaches for studying the travelling salesman problem is a vast subject and only a few important results are mentioned below to supplement the above discussion on the problem on lattices. The normalized optimal contour length per city was calculated by using the universality of the scaling the n-th neighbour distance with the number N of cities where the cities are represented by a set of N points chosen randomly in a unit volume of the )-dimensional hypercube with toroidal boundary conditions [53] = 0.7120 0.0002 in > = 2 and He = 0.6979 0.0002 in > = 3. The mean-field approach [54] in the limit N 00 gives... [Pg.297]

The example discussed in the previous section using the BBOT equations shows that the trajectory of a solid particle tends to align with the direction of the fluid flow. The fluid flow does not exert a lift force on the particle, even if it possesses a velocity gradient in the direction perpendicular to that of the flow. This result contradicts some observations of fluid mechanics. The lack of a lift force, for example, does not allow fluid particles to migrate in the direction perpendicular to the direction of the flow, or the fluid to pick up a particle lying on a wall. The smdy of the lift force has given rise to a considerable amount of research, of which we summarize a few important results. The reader will find in the book by Michaehdes" ... [Pg.341]

A broad class of optimization strategies does not require derivative information. These methods have the advantage of easy implementation and little prior knowledge of the optimization problem. In particular, such methods are well suited for quick and dirty optimization studies that explore the scope of optimization for new problems, prior to investing effort for more sophisticated modeling and solution strategies. Most of these methods are derived from heuristics that naturally spawn numerous variations. As a result, a very broad literature describes these methods. Here we discuss only a few important trends in this area. [Pg.65]

Although the application of carboalumination to the synthesis of natural products is still in its infancy, a few preliminary results shown in Scheme 1.50 [167,168,171,172] suggest that it promises to become a major asymmetric synthetic reaction, provided that (i) the singularly important case of methylalumination can be made to proceed with S90% ee, and (ii) satisfactory and convenient methods for enantiomeric and diastereo-meric separation/purification can be developed. In this context, significant increases in ee in the synthesis of methyl-substituted alkanols from around 75 % to 90—93 % achieved through some strategic modifications are noteworthy (Scheme 1.50) [168]. Shortly before the discovery of the Zr-catalyzed enantioselective carboalumination, a fundamentally discrete Zr-catalyzed asymmetric reaction of allylically heterosubstituted alkenes proceeding via cyclic carbozirconation was reported, as discussed later in this section. [Pg.30]

The book has been written as an introductory text, not as an exhaustive review. It is meant for students at the start of their Ph.D. projects and for anyone else who needs a concise introduction to catalyst characterization. Each chapter describes the physical background and principles of a technique, a few recent applications to illustrate the type of information that can be obtained, and an evaluation of possibilities and limitations. A chapter on case studies highlights a few important catalyst systems and illustrates how powerful combinations of techniques are. The appendix on the surface theory of metals and on chemical bonding at surfaces is included to provide better insight in the results of photoemission, vibrational spectroscopy and thermal desorption. [Pg.10]

Some of the mathematical tools, such as the linear one-box model, are both fairly simple and nonetheless sufficient for handling a great variety of situations. More complex systems require the use of multibox models. In some cases, continuous time-space models are needed. The mathematics of the latter involve partial differential equations and quickly lead beyond the scope of this book. In this chapter, a few important concepts were discussed which allow the reader both to make some approximative calculations and to critically analyze the results from computer models in which time-space processes are employed. [Pg.1044]

Immunoelectrophoresis on agar gels has given splendid results in the differential diagnosis of a few important diseases (B2, B3, G3), but must form the subject of a later review since the technique is still in the course... [Pg.123]

In this chapter we present a few selected results on the nanoscale electrodeposition of some important metals and semiconductors, namely, Al, Ta and Si, in air- and water-stable ionic liquids. Here we focus on the investigation of the electrode/electrolyte interface during electrodeposition with the in situ scanning tunneling microscope and we would like to draw attention to the fascinating... [Pg.240]

Most studies of rotational excitation have already been reviewed earlier [17, 18, 32]. Only a few important previous results will be repeated here and some rather recent measurements will be mentioned. [Pg.91]

The primary objective of most applications carried out so far was to assess the performance of the PPP-VB method for diverse alternant and nonaltemant -electron systems of aromatic, nonaromatic or antiaromatic character, both electrically neutral and charged. The main emphasis was on ground states of different spin multiplicity, even though some preliminary calculations were also carried out for excited states. The PPP-VB codes were also employed to provide the approximate three- and four-body connected cluster components for the so-called VB-corrected coupled cluster (CC) approach [71]. In the following, we briefly point out the most important aspects of the PPP-VB method and illustrate them with a few typical results. [Pg.488]

Except for the endrin-sugar work there has been little reported work relating the contribution of farm use of aldrin or endrin to water contamination. This report deals with studies undertaken in 1964 and 1965 to determine whether the treatment of soil under com, which is an important use, contributes significantly to water contamination. It also contains the results of tests conducted in 1964 to determine whether aldrin, as a rice-seed treatment, contributes to waterway contamination. A few preliminary results reported by Sparr and Mitchell (10) indicated that the contribution was negligible. The results of a 1964 study to determine whether the foliar application of endrin to cotton leads to significant waterway contamination are also reported. [Pg.156]

Though much effort has been made during the last 10 years to detect primary molecules in comets by radio techniques only a few positive results could be achieved (for a review of this very complex subject and for a table of negative results see Snyder It should be emphasized that these observations are very difficult and that the signals are only marginal in most cases. Furthermore, it is not always easy to coordinate the cooperation with radio astronomers in due time when a bright comet appears. With respect to the importance of these observations, all efforts should however be made to continue the search for molecules in the microwave and radio spectra of future comets. [Pg.87]

Enzymes are proteins that catalyze reactions necessary to sustain life. Like other proteins, enzymes consist of chains of amino acids. The structural formulas of a few important amino acids are shown in Figure 29F-1. Molecules formed by linking two or more amino acids are called peptides. Each amino acid in a jjeptide is called a residue. Molecules with many amino acid linkages are polypeptides, and those with long polypeptide chains are proteins. Enzymes differ from other proteins in that a specific area of the structure, called the active site, assists in the catalysis. As a result, enzyme catalysis is often quite specific, favoring a particular substrate over other closely related compounds. [Pg.886]

This classification seems obvious at the first glance, but analysis of specific descriptions of experimental procedures and the results reveals a few important issues to be addressed. [Pg.71]


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