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Acceptance Tools

The first EELS experiments were reported by Propst and Piper in 1967 and concerned the adsorption of H2, N2, CO, H20 on the (100) surface of tungsten [49]. Ibach studied the energy losses of electrons to phonons in ZnO surfaces around 1970 [50] and continued to develop the technique for studying adsorbates on metal surfaces [51,52]. In the 1980s EELS grew further into an extremely important and generally accepted tool in surface science. [Pg.238]

Mass spectrometry (MS) is now a well-accepted tool for the identification as well as quantitation of unknown compounds. The combination of MS with powerful separation methods such as gas chromatography (GC) or high-performance liquid chromatography (LC) provides a technique which is widely accepted for the identification of unknown components in complex mixtures from a wide variety of problems such as environmental pollutants, biological fluids, insect pheromones, chemotaxonomy, and synthetic fuels. The importance of such analyses has grown exponentially in the last few years there are now well over a thousand GC/MS instruments in use around the world, most with dedicated computer systems which make possible the collection from each of hundreds of unknown mass spectra per day (1). [Pg.120]

Phase-transfer catalysis (PTC) is the most widely used method for solving the problem of the mutual insolubility of nonpolar and ionic compounds. Basic principles, synthetic uses, industrial applications of PTC, and its advantages over conventional methods are well documented [1-3]. PTC has become a powerful and widely accepted tool for organic chemists due to its efficiency, simplicity, and cost effectiveness. The main merit of the method is its universality. It may be applied to many types of reactions involving diverse classes of compounds. An important feature of PTC is its computability with other methods for the intensification of biphasic reactions (sonolysis, photolysis, microwaving, etc.) as well as with other types of catalysis, in particular, with transition-metal-complex catalysis. Homogeneous metal-complex catalysis under PTC conditions involves the simul-... [Pg.953]

To date, no universally accepted tool to predict fouling and slagging from coal ash compositions has been developed. Information about the performance of particular coals is frequently not widely available for a variety of reasons. When the information is available from both commercial and small scale studies then... [Pg.7]

The observation of molecular hydrogen by means of its electronic transitions in a sense follows classical optical interstellar spectroscopy. It is, however, considerably more complex, requiring essentially controlled satellite observatories. Thus, it serves to determine molecular-hydrogen column densities in translucent clouds, but cannot provide images of the dense molecular clouds. For these, carbon monoxide is the generally accepted tool. The reported results are in terms of H2 column densities under the assumption that the H2 CO ratio is the accepted value of 10. CO is observable by means of its many isotopomers. This is extremely useful, as the common isotopomer is frequently optically opaque, making... [Pg.372]

Potentiometric dyes have become widely accepted tools. Hundreds of papers in which such dyes are routinely used are published each year. However, the proper and optimal implementation of this technology requires an appreciation of the physical, chemical, and spectral properties of a dye, in addition to its voltage sensitivity. Some knowledge of the potentiometric mechanism also is needed for the intelligent use of a dye. This chapter has attempted to provide this information, but this knowledge can only help narrow the field to a manageable selection of candidates for a particular application. The final choice of the best dye will depend on appropriate experiments to test the candidates. [Pg.175]

Four unusual chlorinated homo diterpenes, hamiltonins A-D (143 - 146), the sesterterpene hamiltonin E (147) and the toxins latrunculin A and B (148, 149) [123], were isolated from the brightly coloured dorid nudibranch Chromodoris hamiltoni (Family Chromodorididae) collected from the Aliwal shoal [124], Since latrunculin A and B were initially shown to cause concentration dependent changes in cell shape and actin organization [125], they have now become the most widely accepted tools for exploring the inhibition of actin polymerization in molecular biology [126],... [Pg.100]

Alternative process chemistries will likely pose different hazards and different degrees of hazard. The comparison of alternatives will inevitably lead to tradeoffs. The chosen candidate, although not devoid of hazards altogether, will likely be the one with the least risk. There is at present no universally accepted tool to judge among alternatives (see discussion in Sections 2.4 and 2.5). Edwards et al. [Pg.65]

There is no doubt as to the remarkable potential of the EC-MS technique for the analysis of biotoxins it represents a serious alternative to the mouse bioassay or, at least, a supplementary analytical tool for tracing an extensive toxin profile of contaminated shellfish. The current rapid developments in EC-MS methodology look promising for a close attainment of these objects however, further improvement and interlaboratory studies will be necessary. In addition, a serious problem, which does not allow, at present, this technique from becoming a generally accepted tool in regulatory analysis is the nonavailability of pure analytical standards and reference materials for most YTXs. [Pg.309]

Effective machining of spheroidal irons with mixed microstructures can be performed using coated silicon nitride ceramic and CBN tools. This is due to the fact that these cutting tool materials guarantee acceptable tool life at reasonably high cutting speeds up to 400 m/min. [Pg.814]

System safety continues, in many cases, to be more of an art than a science. The quality of system safety products is determined by the skill and talent of the individual analyst, not by the systematic application of accepted tools and techniques. [Pg.402]

Nowadays, drawings are an accepted tool in cognitive psychology when it comes to gaining insights into a person s mental representations. Mental images are seen... [Pg.260]

The mathematics of spherical harmonics is an accepted tool in many scientific disciplines and is treated in several classic texts. In 1939 the method was applied to orientation in materials by Hermans and Platzek, who used just P2), which is often referred to as the Hermans orientation function. Spherical harmonics were applied to liquid crystals in the theoretical work of Maier and Saupe, who again emphasized only (Pj)- However, they called it the order parameter and designated it S, setting a nomenclature which is now standard in liquid crystal studies. [Pg.123]

Multi-purpose CFD codes are nowadays a frequently used and well accepted tool in academia and industry. Already the available standard codes must be regarded as powerful tools that can be successfully applied to various technical disciplines including combustion processes. In this field at present the real value in CFD calculations lies in predicting trends that occur when operational conditions are changed. This statement is true for the above presented ash deposition predictions as well as for the NO emission predictions and is validated for both cases with experimental data. However, in the future the real power of CFD codes lays in the possibility to extend and adjust them with process specific data to tailor-made tools applicable to address individual technical problems and specific questions. The successfully developed and validated simplified black liquor droplet combustion model presented in this paper proves this assessment. [Pg.814]


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See also in sourсe #XX -- [ Pg.127 , Pg.153 , Pg.156 , Pg.157 ]




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Reviewing a Few Examples of Acceptance Tools

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