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Bell formula

It is possible to derive tunnel corrections for functional forms of the energy barrier other than an inverted parabola, but these cannot be expressed in analytical form. Since any barrier can be approximated bv a parabola near tbe TS, and since tunnelling is most important for energies just below the top, they tend to give results in qualitative agreement with the Bell formula. [Pg.391]

Note that this formula can be easily obtained from Gauss s theorem of the induced charges, which, in this case, will be equal to — q — s)/( w s)- The coefficient 1/2 comes from the linear-response hypothesis. Another useful formula is the solvation energy of the point dipole (/j.) in the center of a spherical cavity [29] (Bell formula, sometimes also called the Onsager formula) ... [Pg.267]

Mirex is a white, odorless, free-flowing, crystalline, nonflammable, polycyclic compound composed entirely of carbon and chlorine. The empirical formula is C10C112, and the molecular weight 545.54 (Hyde 1972 Waters et al. 1977 Bell et al. 1978 NAS 1978 Menzie 1978 Kaiser 1978). In the United States, the common chemical name is dodecachlorooctahydro-l,3,4-metheno-2H-cyclobuta[c,systematic name is dodecachloropentacyclo 5.3.0.02-6.03 9.04 8decane. Mirex was first prepared in 1946, patented in 1955 by Allied Chemical Company, and introduced... [Pg.1134]

This approximate inversion formula is quite accurate for bell shaped or mono-tonically increasing functions f (E). It can be substantially improved by iteration. One Laplace transforms the function f i [E) and then applies STILT to the difference function f(P) - fi(P). The iterated inversion formula is exact for the class... [Pg.28]

The shell-side pressure drop is calculated using the formula proposed by Bell (Ref. E2 p.558), and given in Chapter 10 as Equation 10.8. Therefore,... [Pg.321]

Pendry, B., Busia, K. and Bell, C.M. (2005) Phytochemical evaluation of selected antioxidant-containing medicinal plants for use in the preparation of a herbal formula - a preliminary study. Chemistry and Biodiversity 2(7), 91 7-922. [Pg.411]

Evaluation of the HH ROESY (c) verifies the amino acid sequence of the cyclopentapeptide lactone ring attached to C-9 of actinocin by means of the NOE induced spatial correlation signals la-belled a d in the formula C. The a- and (3-protons of threonine in both cyclopentapeptide lactone rings are sufficiently separated but close to each other. This applies to the other amino acid protons with the exception of TV-methylvaline, in which proton signals overlap (Table 55.1). Therefore, starting from the a- and [3-protons of threonine 8H = 4.61 and 5.75), the sequence Thr-Vai-Pro-Sar-MeVal attached to C-l of actinocin is similarly verified in the HH ROESY as shown in formula C. The connection Sar-MeVal is established by the spatial correlations d between the 72-protons of sarcosine and the A7-methyl-protons of 7V-methylvaline in both rings (SH = 4.71/2.92 and 4.78/2.89). [Pg.248]

Bell et al. [33] proposed an analytical formula, widely known in the literature as the Belfast ionization (BELI) formula [34] that contains the dipole interaction term for the electron-impact ionization of atoms and ions. It has been applied to light atomic and ionic targets with species-dependent parameters. Godunov and Ivanov [34] applied the BELI formula to the El ionization of Ne 1 ions. Here also no generality as to parameters of the formula was provided regarding the species-dependent parameters. Moreover, the BELI formula does not make any allowance for relativistic effects. Haque et al. [35-38] have proposed a modification of this BELI model for evaluating the El K-, L-, and M-shell ionization cross sections of atoms. The relativistic and ionic effects are also incorporated in their modified BELI (MBELL) [35-38] model in addition to generalizing the species-independent... [Pg.319]

Lonsdale, K. (1936). Simplified Structure Factor and Electron Density Formulae for the 230 Space-Groups of Mathematical Crystallography. G. Bell Sons, London. [Pg.374]

However, the CKou Li formulas do have some basis with regards to the properties of the various alloys. Vessels and bells do not need great hardness they should be durable and, in the case of bells, somewhat... [Pg.317]

This compound is a high-nuclearity complex with the formula [Mn(III)9Mn(II)2 Gd(III)2O8(OH)2(piv)i0.6(fca)6.4(NO3)2(H2O)]-13CH3CN H2O, where pivH = t-BuCOOH, fcaH = 2-furan-carboxylic acid. The 13-nuclei complex can be described as bell-shaped and the two Gd ions are the bell s clapper (Figure 9.24). [Pg.386]

Determination offs,fsi and/ . The formula for microorganisms has been given as C5H7NO2 (Mandt and Bell, 1982). To find the oxygen equivalent of the mass synthesized, /j, react this molecule with oxygen as follows ... [Pg.456]

An ocryphal story is told of a math major showing a psychology major the formula for the infamous bell-shaped curve or gaussian, which purports to represent the distribution of human intelligence and such. The formula for a normalized gaussian looks like this ... [Pg.206]

According to Bell (3), Cl-TSP has the empirical formula 4(Na3P04-XH20) NaY, where X=ll-12 and Y is OCl. This empirical formula, however, is not in agreement with the composition given by Mathias (4) and Alder (5). The earlier inventors showed that Cl-TSP has a Na/P mole ratio to be less than three. The Bell proposed formula has been well accepted and a term, chlorinated trisodium phosphate has often been used, as depicted by reaction 1 below. Unfortunately, the implied chemical reaction, chlorination of crystalline trisodium orthophosphate, does not produce the desired product, Cl-TSP. Some clarification of this preparation is needed. [Pg.241]

There are probably more than 50 US patents related to Cl-TSP. Additives, from surfactants to silicates, were used to produce crystals with more stable active chlorine. Examples of these patents are references (6-13) which apparently followed Bell s proposed formula. [Pg.241]

Keen CL, Bell JG, Lonnerdal B. 1986. The effect of age on manganese uptake and retention from milk and infant formulas in rats. J Nutr 116 395-402. [Pg.463]

Glutton s Febrifuge Spirit. The original formula is oil of sulphur by the bell, ou of vitriol and sea salt, of each 1 ounce rectified spirit, 3 ounces mix, digest for a month, and distill to dryness. [Pg.308]

Formula of acid EO (OH) notation Oxidation state of E PK,(1) piSTaCl) estimated by using Bell s rule... [Pg.171]

Bell-Evans-Polyani Relationship. The Bell-Evans-Polyani formula deals with the relationship between reaction rate and exothermicity for a series of related single-step reactions. Evans and Polyani pointed out that for a series of homolytic atom transfer reactions of the general type... [Pg.288]

Case Reports A few case reports showed only a transitory increase of TSH during soy-based food consumption. Jabbar et al. (1997), Conrad et al. (2004), and Bell and Ovalle (2001) report on higher thyroxine substitution required by hypothyroid children consuming soy-based formulas. The latter authors concluded that concurrent administration of thyroid hormone with a soy dietary supplement leads to decreased absorption of levothyroxine and the need for higher oral doses to attain therapeutic thyroid hormone levels. [Pg.357]

An exact analytical solution has been found for a symmetric parabolic potential barrier by BELL /65/. A generalization of this solution for an asymmetric parabolic barrier described by (79 11) is given by CHRISTOV /66/. For this purpose use is made of the formula(81. II) for W>j2 9 which gives the expression... [Pg.184]


See other pages where Bell formula is mentioned: [Pg.203]    [Pg.269]    [Pg.203]    [Pg.269]    [Pg.248]    [Pg.669]    [Pg.760]    [Pg.167]    [Pg.428]    [Pg.303]    [Pg.94]    [Pg.179]    [Pg.327]    [Pg.315]    [Pg.31]    [Pg.281]    [Pg.269]    [Pg.138]    [Pg.469]    [Pg.253]    [Pg.109]    [Pg.63]    [Pg.339]   
See also in sourсe #XX -- [ Pg.267 , Pg.269 ]




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Bell

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