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Simple numbers

The number k is more than just a simple number to designate a wave function. According to the de Broglie equation, p = h/X, every electron can be assigned a momentum p (h = Planck s constant), k and the momentum are related ... [Pg.91]

Data from attrition tests are usually presented as simple numbers called friability or attrition indices. Most of these indices are used as measures in quality control by subjecting the materials to a standard procedure. By comparing the test results with those of known materials, it is possible to give a relative characterization of the tested materials. Examples are given in Sec. 4.3. [Pg.446]

The concept of potential energy in mechanics is one example of a scalar field, defined by a simple number that represents a single function of space and time. Other examples include the displacement of a string or a membrane from equilibrium the density, pressure and temperature of a fluid electromagnetic, electrochemical, gravitational and chemical potentials. All of these fields have the property of invariance under a transformation of space coordinates. The numerical value of the field at a point is the same, no matter how or in what form the coordinates of the point are expressed. [Pg.107]

For the simple case of one unpaired electron (5 = 1/ 2), the associated magnetic moment is not a simple number but is directionally oriented—that is, is anisotropic. Taking spin-orbit interactions into account for EPR spectra leads to four limiting cases ... [Pg.89]

Occasionally, the temperature voltage coefficient is not expressed as a simple number, but as apower series in T (we generally call it a virial series, or expansion). For example, Equation (7.19) cites such a series for the cell Pt(S) H2(g) HBr(aq) AgBr(s) Ag(s) ... [Pg.297]

Most categories of port have a gender (such as input and output ) and a type of value that is transmitted, from simple numbers to complex objects such as reservations or stock dealings. These elements also are defined by the specific component architecture, which also must define the rules whereby the ports can be connected (for example, an input always to an output). [Pg.437]

Most photochemical reactions are composite reactions that is, they can be regarded as being made up of several elementary steps, constituting the mechanism, each of which involves a simple number of species. The... [Pg.186]

The term valence, of which ambivalence is not merely a variation, but a decidedly new and separate concept, derives from chemistry and atomic physics. Valence can refer to an extract or tincture, usually from an herb. In this connotation, it has obvious ties with the field of medical alchemy, or iatrochemistry. In the mid-i8oos, valence theory began to be used to signify the normal number of bonds that a given atom can form with other atoms—a register that links valence with philosophical materialism, matter, and Epicurianism. In recent scientific work, valence refers specifically to the number of electrons in the outermost shell of atoms. It is not provisional or occasional in its relation to the atom. Valence is atomicity. It defines a given chemical element, perhaps not in its essence, but in its capacity to combine with other elements—its potentiality. Valence is denoted by a simple number, and elements are said to be monovalent, bivalent, trivalent, quadrivalent, and so on. About one-fifth of all elements have a fixed valence (sodium is always i, or monovalent calcium is always 2, or bivalent and so on). Many elements have valences that are variable, depending on the other elements with which they are combined. [Pg.55]

For products of a operators one finds again a generalized Wick theorem like Eqs. (10) and (11), but in addition to particle contractions we also have hole contractions and combined contractions, even full contractions, that is, simple numbers ... [Pg.310]

You are asked to find a simple number, not a sum, product, difference, or ratio. [Pg.161]

An algebra typically involves the operations of adding, subtracting, multiplying, or dividing the objects it describes, whether matrices or simple numbers. For completeness, we now summarize some other aspects of matrix algebra, built on the fundamental definitions of addition/subtraction (9.8), scalar multiplication (9.9), and matrix multiplication (9.11). [Pg.319]

There is one metric unit with a special name that scientists frequently use because it permits the use of simple numbers when talking about the sizes of atoms and molecules. It is called an angstrom (A) 1 A = 10 8 cm-... [Pg.35]

Do not worry about this Instead, realize that there will always be a little experimental error that you will have to allow for Normally, look for relatively simple numbers for subscripts... [Pg.150]

A rather complicated relationship between a(T) and P is, however, expressed in Fig. 15, because these curves are parametrized by a MWD w(P) as indicated, and not by a simple number, Pw, like those from Fig. 14 (cf. Sect. 5)... [Pg.26]

Although the above algebraic formula seems rather complex, in fact it reduces to simple numbers. Therefore, a tabulation of these coefficients is a useful tool (Table 49). To this end one gets the final formulae shown in Table 5. [Pg.35]

Because of its conciseness, the ESS easily fits on a single 8x11 sheet of paper, and takes less than 3 min for patients or families to complete. Its items are short, simple, easily understandable even by poorly educated patients, and it yields a simple number (from 0 to 24). Unlike the SSS, which refers to a state at a particular time of the day or night, the ESS refers to a general state, and is more suited to evaluate disease versus health. For those reasons, it is currently and by far the most used sleepiness scale, both in clinical practice and in research. [Pg.5]

A measure that has been the subject of extensive publication is that of microreactors with catalytically coated walls (7,8). A microreactor has been defined as a miniaturized reaction vessel with characteristic dimensions in the range 10-300 pm which has been fabricated using state-of-the-art high-precision engineering (7). Such reactors exhibit well-defined laminar-flow patterns and permit facile scale-up by simple numbering up of the number of channels and flexible... [Pg.394]

Discussions of heteroatoms in the SHM written in the heyday of that method present the heteroatom parameters in a slightly more complicated way, in terms of the coulomb and resonance integrals a and p, rather than as simple numbers. [Pg.614]

It was noted181 that further simplification could be made by a simple number replacement for consecutive methylene groups therefore, this complete fractal notation can be simplified (or condensed) to ... [Pg.46]

From this we can obtain a value which relates to how well die experiment obeys a linear model, often referred to as an error, or by some statisticians as a variance. However, this error is a simple number, which in the case discussed will probably be expressed in absorbance units (AU). Physical interpretation is not so easy. Consider an error that is reported as 100 mAU this looks large, but then express it as AU and it becomes 0.1. Is it now a large error The absolute value of die error must be compared with something, and here the importance of replication comes into play. It is useful to... [Pg.20]

In Table 8.6(a) the electric field strengths F (expressed in au) are simple numbers, which we have considered as exact values in atomic units. In Table 8.6(b) the electric field strengths F are originally given in V/cm and have been converted into au by conversion factors which we do not know exactly. After certain difficulties with these conversion factors we have in the third- and fifth-order approximations with 4> included been able to reproduce all digits in the numerically exact values of E obtained by Kolosov (1983). To achieve this result, we have used the conversion factor 1 au = 5.142 x 10-9 V/cm for the states with n = 13 and n = 14 and the conversion factor 1 au = 5.142 260 3 x 10-9 V/cm for the state with n = 30 it is not possible to reproduce all digits in the numerically exact results by the use of one and the same conversion factor. [Pg.111]

This brings us back to Balmer, the high-school mathematics teacher. By the time Balmer became interested in the problem, the spectra of many chemical elements had been studied and it was clear that each element gave rise to a unique set of spectral lines. Balmer was a devoted Pythagorean he believed that simple numbers lay behind the mysteries of nature. Thus, his interest was not directed toward spectra per se, which he knew little about, nor was it directed toward the discovery of some hidden physical mechanism inside the atom that would explain the observed spec-... [Pg.23]

Composition and sequence data 63,86). Simple numbers for peptides refer to Matthews el al. 63), while alpha-numeric designations refer to Brown and Perham 86). — represents a residue placed by the dansyl-Edman or the subtractive-Edman procedures. R/ refers to peptide mobility on electrophoresis at pH 6.5 relative to the mobility of aspartic acid ( — 1.0). [Pg.121]

Learn to use the calculator well with simple numbers to be able to check the procedures easily before trying to do chemical calculations that take concentration. [Pg.605]

Advantage All the steric impact is compacted into one simple number. [Pg.25]

Currently two synonymous names are mainly used for the different members of the coronin protein femily. One is based on a simple numbering system for mammalian coronins 1 -7, while the other employs a number-letter system to specify coronins lA (= 1), IB (= 2), 1C (= 3),2A( = 4) and2B (= The current official nomenclature for vertebrate coronins from the HGNC (Human... [Pg.99]


See other pages where Simple numbers is mentioned: [Pg.238]    [Pg.14]    [Pg.11]    [Pg.110]    [Pg.38]    [Pg.202]    [Pg.116]    [Pg.133]    [Pg.258]    [Pg.8]    [Pg.167]    [Pg.334]    [Pg.235]    [Pg.110]    [Pg.301]    [Pg.557]    [Pg.551]    [Pg.3]    [Pg.273]    [Pg.37]    [Pg.12]    [Pg.46]   
See also in sourсe #XX -- [ Pg.227 , Pg.228 , Pg.229 , Pg.230 ]




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The Roles of Simple Numbers and Symmetry in Chemical Reactivity

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