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General Extensions

9 General Extensions. - Bader applied ideas of AIM to the atomic force microscope (AFM). In a quantum system, the force exerted on the tip is the Ehrenfest force, a force that is balanced by the pressure exerted on every element of its surface, as determined by the quantum stress tensor. The surface separating the tip from the sample is an IAS. Thus the force measured in the AFM is exerted on a surface determined by the boundaries separating the atoms in the tip from those in the sample, and its response is a consequence of the atomic form of matter. This approach is contrasted with literature results that equate it to the Hellmann-Feynman forces exerted on the nuclei of the atoms in the tip. [Pg.402]

Bader refuted a variety of objections raised against AIM. In particular he [Pg.402]


In addition to the above general extensions of the Hammett equation in the sense in which it was originally conceived, there have been a number of attempts to refine the equation and extract more detailed information from it, or provide more general justification for it. [Pg.212]

The WLF approach is a general extension of the VTF treatment to characterize relaxation processes in amorphous systems. Any temperature-dependent mechanical relaxation process, R, can be expressed in terms of a universal scaling law ... [Pg.508]

Adverse effects of colloids are generally extensions of their pharmacologic activity (e.g., fluid overload, dilutional coagulopathy). Albumin and dex-tran may be associated with anaphylactoid reactions or anaphylaxis. Bleeding may occur in certain patients receiving hetastarch and dextran. [Pg.163]

Generally, extensive prior information is known about the sample in terms of the elemental composition and in these cases methods of analysis can be selected that will provide the desired result. However, if this information is not available or else a more general survey of ultratrace elements is required, then AES with an inductively coupled plasma source is the only atomic spectrometric technique that can provide these data at ultratrace levels. [Pg.248]

Metal-catalyzed olefin metathesis had an enormous impact on organic synthesis in general. Extensive research on mechanistic aspects (3,4) and the development of catalysts has been performed, which culminated in the award of the Nobel Prize for Chemistry in 2005 to Chauvin, Grubbs and Schrock. [Pg.1]

For example, the Langmuir adsorption isotherm specifically describes adsorption of a single gas-phase component on an otherwise bare surface. When more than one species is present or when chemical reactions occur, the functional form of the Langmuir adsorption isotherm is no longer applicable. Thus, although such simple functional expressions are very useful, they are not generally extensible to describe arbitrarily complex surface reaction mechanisms. [Pg.453]

Figure 5.1 Schematic plots of (a) constrained entropy Sjj and (b) unconstrained entropy S as functions of a general extensive property X near equilibrium, Xeq. In each case, the negative curvature of the entropy function (constrained or unconstrained) carries it below its equilibrium tangent (dashed line). Figure 5.1 Schematic plots of (a) constrained entropy Sjj and (b) unconstrained entropy S as functions of a general extensive property X near equilibrium, Xeq. In each case, the negative curvature of the entropy function (constrained or unconstrained) carries it below its equilibrium tangent (dashed line).
Single-variable plots of Sy(X) or S(X) such as those shown in Fig. 5.1 do not yet convey a geometrical picture of the multivariate entropy function in higher dimensions. Figure 5.2 shows a more complete 3-dimensional SUX view of the S(U,X) surface for a general extensive variable X. [Pg.159]

The original theory of individual state-selective vibrational transitions induced by IR femtosecond/picosecond laser pulses has been developed by Paramonov and Savva et al. for single laser pulses [13] (see also Ref. 23) followed by more general extensions to series of IR femtosecond/picosecond laser pulses in Refs. 14 and 24. For illustration, let us consider two simple, one-dimensional model systems that are assumed to be decoupled from any... [Pg.328]

Obvious complications as compared to simple systems arise in the case of molecular targets. The potentials V (R) and V+(R) and also the width T(f ) depend on the relative orientation of the molecule to the metastable-target direction. In addition, there is the possibility of vibrational and rotational transitions in the ionization process as well as the possibility of reaction before and after the ionization. No general extension of the Pgl theory to the case of molecular targets has been formulated. [Pg.463]

Networks are generally extensions of distributed processing. They may consist of connections between complete computer systems that are geographically distant, or they may consist of computer systems on a LAN in the same facility. [Pg.67]

Many 1,2,3-selenadiazoles have been prepared as intermediates for the ultimate preparation of other organic compounds or for biological activity evaluation [6], The most general, extensively applied method is based on the oxidation of semicar-bazones, mostly derived from aromatic and carbocyclic ketones, by selenium dioxide [6, 14, 188-191], Synthesis of 4-(2-naphthyl)-l,2,3-selenazole (117) from semicarbazone (116) is an example (Scheme 36). [Pg.314]

To calculate a general extensive property, X, of a solution, we start with a differential relation for X ... [Pg.228]

In general, extensive use of in-process storage areas should be avoided. It is best to operate the aseptic facility in a just-in-time mode in which components and equipment are sterilized shortly before they are required for use in the filling or compounding areas. Some limited storage is necessary for nonproduct contact materials such as sanitizing agents, environmental supplies and equipment, and other items. [Pg.110]

In principle, simple crown ethers can be prepared by cyclooligomerization of ethylene oxide. This reaction has been reported. Although 12- to 18-membered ring crowns were obtained, the major product was invariably dioxane. This may be a useful method to obtain these simple crowns inexpensively but it is neither generally extensible <1976CC295> nor particularly adaptable to the research laboratory. [Pg.805]

Other relativistic correction integrals are also discussed as a general extension of one and two electron Coulomb operators, in a context where it is discussed a scheme to deal with one and two electron integrals using a common point of view. [Pg.208]

Pharmacokinetics. Absorption of xanthines after oral or rectal administration varies with the preparation used. It is generally extensive (> 95%). Caffeine metabolism varies much between individuals (t/ 2-12 h). Xanthines are metabolised (more than 90%) by numerous mixed function oxidase enzymes, and xanthine oxidase. (For further details on theophylline, see Asthma.)... [Pg.194]

Hunig and co-workers have described violene systems where the benzo-thiazole or benzoxazole parts are separated by a polyene chain the consequence for the formation constants of the radical-cation (e.g., 216) of variation in n was studied. The consequences of aza substitution in the chain were also studied. In general, extension of the conjugation destabilizes the radical-cation relative to the upper and lower oxidation states. (See also Part I Section II,B,2.)... [Pg.118]

Chlorinated hydrocarbon pesticide residues in human adipose tissue and liver tissue samples have been identified by mass spectrometry coupled with gas chromatography. A general, extensive extraction and cleanup procedure adapted from existing methods was used to isolate... [Pg.141]

Although the phase equllibritim in binary mixtures of simple molecules and biomolecules has been modeled fairly successfully, a general extension of this approach to more complex, multi-component systems remains a challenge. [Pg.109]


See other pages where General Extensions is mentioned: [Pg.141]    [Pg.66]    [Pg.876]    [Pg.884]    [Pg.1086]    [Pg.112]    [Pg.311]    [Pg.336]    [Pg.337]    [Pg.217]    [Pg.593]    [Pg.441]    [Pg.3]    [Pg.157]    [Pg.876]    [Pg.884]    [Pg.1086]    [Pg.297]    [Pg.245]    [Pg.30]    [Pg.418]    [Pg.10]    [Pg.42]    [Pg.136]    [Pg.1228]    [Pg.225]    [Pg.362]    [Pg.171]   


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