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Expression definition

A commonly expressed definition is Thermal Comfort is that condition of mind that expresses satisfaction with the thermal environment. The definition implies that the judgment of comfort is a mental process that results from physical, physiological, and psychological factors and processes. Dissatisfac tion can lead to complaints and other undesirable side effects. [Pg.175]

The legislative history of the original CPSA confirms the Congressional desire to balance a proposed standard s benefits to consumer safety against its drawbacks in other areas of consumer welfare. S. 3419, the Senate version of the Act, included an express definition of unreasonable risk of injury ... [Pg.341]

Synonyms Fats, nutmeg butter Mace oil Mace oleoresin Macis oil Myristica fragrans Myristica fragrans oil Myristica fragrans oleoresin Nutmeg oil, expressed Definition Volatile oil from steam distillation of dried aril of ripe seed of Myristica fragrans Empirical C7H5CIO... [Pg.2440]

FIGURE 1.34 Example of forms for defining boolean functions (a) boolean expression definition, (b) boolean expression evaluation, (c) truth table definition. [Pg.49]

This dictionary puts the pleasure back into word-seeking. Every time you look at a page you get a bonus - a panel telling you everything about a particular word or expression. It is, therefore, a dictionary to be read as well as used for its concise and up-to-date definitions. [Pg.438]

The total interaction between two slabs of infinite extent and depth can be obtained by a summation over all atom-atom interactions if pairwise additivity of forces can be assumed. While definitely not exact for a condensed phase, this conventional approach is quite useful for many purposes [1,3]. This summation, expressed as an integral, has been done by de Boer [8] using the simple dispersion formula, Eq. VI-15, and following the nomenclature in Eq. VI-19 ... [Pg.232]

The quantity zoi will depend very much on whether adsorption sites are close enough for neighboring adsorbate molecules to develop their normal van der Waals attraction if, for example, zu is taken to be about one-fourth of the energy of vaporization [16], would be 2.5 for a liquid obeying Trouton s rule and at its normal boiling point. The critical pressure P, that is, the pressure corresponding to 0 = 0.5 with 0 = 4, will depend on both Q and T. A way of expressing this follows, with the use of the definitions of Eqs. XVII-42 and XVII-43 [17] ... [Pg.614]

The general expression for particle scattering can best be described by the correlation fimction y(r). Using the definition in ( Bl.9.48). we have... [Pg.1398]

The first requirement is the definition of a low-dimensional space of reaction coordinates that still captures the essential dynamics of the processes we consider. Motions in the perpendicular null space should have irrelevant detail and equilibrate fast, preferably on a time scale that is separated from the time scale of the essential motions. Motions in the two spaces are separated much like is done in the Born-Oppenheimer approximation. The average influence of the fast motions on the essential degrees of freedom must be taken into account this concerns (i) correlations with positions expressed in a potential of mean force, (ii) correlations with velocities expressed in frictional terms, and iit) an uncorrelated remainder that can be modeled by stochastic terms. Of course, this scheme is the general idea behind the well-known Langevin and Brownian dynamics. [Pg.20]

Depending on the application, models of molecular surfaces arc used to express molecular orbitals, clcaronic densities, van dor Waals radii, or other forms of display. An important definition of a molecular surface was laid down by Richards [182] with the solvent-accessible envelope. Normally the representation is a cloud of points, reticules (meshes or chicken-wire), or solid envelopes. The transparency of solid surfaces may also be indicated (Figure 2-116). [Pg.125]

Besides the expressions for a surface derived from the van der Waals surface (see also the CPK model in Section 2.11.2.4), another model has been established to generate molecular surfaces. It is based on the molecular distribution of electronic density. The definition of a Limiting value of the electronic density, the so-called isovalue, results in a boundary layer (isoplane) [187]. Each point on this surface has an identical electronic density value. A typical standard value is about 0.002 au (atomic unit) to represent electronic density surfaces. [Pg.129]

The most well-known and at the same time the earliest computer model for a molecular structure representation is a wire frame model (Figure 2-123a). This model is also known under other names such as line model or Drciding model [199]. It shows the individual bonds and the angles formed between these bonds. The bonds of a molecule are represented by colored vector lines and the color is derived from the atom type definition. This simple method does not display atoms, but atom positions can be derived from the end and branching points of the wire frame model. In addition, the bond orders between two atoms can be expressed by the number of lines. [Pg.132]

This expression now defines the dot or inner produet (Hermitian inner produet) for veetors whieh ean have eomplex valued eomponents. We use this definition so the dot produet of a eomplex valued veetor with itself is real. [Pg.528]

The results of electrostatic potential calculations can be used to predict initial attack positions of protons (or other ions) during a reaction. You can use the Contour Plot dialog box to request a plot of the contour map of the electrostatic potential of a molecular system after you done a semi-empirical or ab initio calculation. By definition, the electrostatic potential is calculated using the following expression ... [Pg.244]

Uncertainty expresses the range of possible values that a measurement or result might reasonably be expected to have. Note that this definition of uncertainty is not the same as that for precision. The precision of an analysis, whether reported as a range or a standard deviation, is calculated from experimental data and provides an estimation of indeterminate error affecting measurements. Uncertainty accounts for all errors, both determinate and indeterminate, that might affect our result. Although we always try to correct determinate errors, the correction itself is subject to random effects or indeterminate errors. [Pg.64]

Two further expressions are used in discussions on isotope ratios. These are the atom% and the atom% excess, which are defined in Figure 48.6 and are related to abundance ratios R. It has been recommended that these definitions and some similar ones should be used routinely so as to conform with the system of international units (SI). While these proposals will almost certainly be accepted by mass spectrometrists, their adoption will still leave important data in the present format. Therefore, in this chapter, the current widely used methods for comparison of isotope ratios are fully described. The recommended Sl-compatible units such as atom% excess are introduced where necessary. [Pg.361]

Dividing the numerator and denominator of Eq. (6.53) by 2kj [M-] and recalling the definition of v provided by Eq. (6.36) enables us to express this result more succinctly as... [Pg.381]

With these definitions in mind, we can immediately write expressions for the ratio of the total number p of iso triads to the total number of syndio triads ... [Pg.486]

Because of the interrelationship of the system measures, rehabihty should not be considered by itself since, if taken alone, it does not express the totahty of attributes that contribute to system effectiveness. However, in practice, rehabihty has gained the most acceptance and uniformity of definition. The other concepts described are not always defined uniformly from group to group and are sometimes used interchangeably. Further discussion of these concepts is found in References 1 and 2. [Pg.4]

Basic Standards for Chemical Technology. There are many numerical values that are standards ia chemical technology. A brief review of a few basic and general ones is given hereia. Numerical data and definitions quoted are taken from References 16—19 (see Units and conversion factors) and are expressed ia the International System of Units (SI). A comprehensive guide for the appHcation of SI has been pubUshed by ASTM (20). [Pg.20]


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