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Moments number

In the case of preservation of the zeroth and third moments (number and mass respectively) the equations for the agglomeration term can be written in the following form... [Pg.176]

MD simulations in expHcit solvents are stiU beyond the scope of the current computational power for screening of a large number of molecules. However, mining powerful quantum chemical parameters to predict log P via this approach remains a challenging task. QikProp [42] is based on a study [3] which used Monte Carlo simulations to calculate 11 parameters, including solute-solvent energies, solute dipole moment, number of solute-solvent interactions at different cutoff values, number of H-bond donors and acceptors (HBDN and HBAQ and some of their variations. These parameters made it possible to estimate a number of free energies of solvation of chemicals in hexadecane, octanol, water as well as octanol-water distribution coefficients. The equation calculated for the octanol-water coefficient is ... [Pg.389]

Here we put the fine structure constant a=l. The moment number writes as ... [Pg.287]

A ratio of the second moment to the first moment (number-average molecular weight) is called the weight-average molecular weight, My, which is the average based on the weight of each polymer chain ... [Pg.85]

M N S moment number of transfer units specific area packing 2/ 3 m /m ... [Pg.406]

The moments of normalized distributions are products of dimensionless frequencies and dimensionless molecular weights or of gram-moles with dimensions of mass. The former moments will be unitless, and the units of the latter will depend on the moment number and on the units of the distribution. Most equations in polymer science imply use of gram-moles, but this is not universal and the dimensions of the particular equation should be checked to determine which units, if any, are being used for molecular weight and concentration quantities. [Pg.49]

MHz for a Abundance at Constant Moment Number Moment Ratio" y... [Pg.216]

Consider for a moment numbers and mathematics. Without getting to far into the debate about what numbers and mathematics actually are, it is worth discussing a few basic points about these areas. Firstly, in most primitive cultures, there is only a very limited number system present in ihe language one might find a word for one, two and three, then a word for a few and a word for lots. [Pg.33]

An heuristic combination of original features may also be used to generate new features however, such methods are extremely problem-depen-dent. Bender, Kowalski and Shepherd C16, 173 investigated several possibilities for the representation of mass spectra means, moments, number of peaks, histograms, etc. were successfully used as new features. [Pg.105]

Equipment data, such as operational hours elapsed since refiner plates were last replaced or changed direction number of refiners sending steam to heat recovery at any given moment number of feedguard events, indicating refiner blockages refiner body temperature. [Pg.1026]

Although a diatomic molecule can produce only one vibration, this number increases with the number of atoms making up the molecule. For a molecule of N atoms, 3N-6 vibrations are possible. That corresponds to 3N degrees of freedom from which are subtracted 3 translational movements and 3 rotational movements for the overall molecule for which the energy is not quantified and corresponds to thermal energy. In reality, this number is most often reduced because of symmetry. Additionally, for a vibration to be active in the infrared, it must be accompanied by a variation in the molecule s dipole moment. [Pg.57]

From complex cuts characterized in an overall manner, there is a transition towards mixtures containing only a limited number of hydrocarbon families or even compounds. This development has only just begun. It affects for the moment only certain products and certain geographical zones. It is leading gradually to a different view of both refining and the characterization of petroleum products. [Pg.484]

Imagine for a moment that the exploration activities carried out in the previous section have resulted in a successful discovery well. Some time will have passed before the results of the exploration campaign have been evaluated and documented. The next step will be the appraisal of the accumulation, and therefore at some stage a number of additional appraisal wells will be required. The following section will focus on these drilling activities, and will also investigate the interactions between the drilling team and the other E P functions. [Pg.29]

Because mole numbers are additive, it follows that the product A. A V will be an additive quantity provided that a for each species remains constant during the course of the reaction. This last condition implies, essentially, that the effective dipole moments and hence the orientation of each species remain constant, which is most likely to be the case at constant film pressure. Then... [Pg.152]

The rotational energy of a rigid molecule is given by 7(7 + l)h /S-n- IkT, where 7 is the quantum number and 7 is the moment of inertia, but if the energy level spacing is small compared to kT, integration can replace summation in the evaluation of Q t, which becomes... [Pg.583]

Equation XVI-21 provides for the general case of a molecule having n independent ways of rotation and a moment of inertia 7 that, for an asymmetric molecule, is the (geometric) mean of the principal moments. The quantity a is the symmetry number, or the number of indistinguishable positions into which the molecule can be turned by rotations. The rotational energy and entropy are [66,67]... [Pg.583]

These moments are related to many physical properties. The Thomas-Kulm-Reiche sum rule says that. S (0) equals the number of electrons in the molecule. Other sum rules [36] relate S(2),, S (1) and. S (-l) to ground state expectation values. The mean static dipole polarizability is md = e-S(-2)/m,.J Q Cauchy expansion... [Pg.193]

The rotational states are characterized by a quantum number J = 0, 1, 2,. .. are degenerate with degeneracy (2J + 1) and have energy t r = ) where 1 is the molecular moment of inertia. Thus... [Pg.406]

Another important characteristic of the late stages of phase separation kinetics, for asynnnetric mixtures, is the cluster size distribution fimction of the minority phase clusters n(R,z)dR is the number of clusters of minority phase per unit volume with radii between R and + cW. Its zeroth moment gives the mean number of clusters at time r and the first moment is proportional to die mean cluster size. [Pg.734]

The interaction of the electron spin s magnetic dipole moment with the magnetic dipole moments of nearby nuclear spins provides another contribution to the state energies and the number of energy levels, between which transitions may occur. This gives rise to the hyperfme structure in the EPR spectrum. The so-called hyperfme interaction (HFI) is described by the Hamiltonian... [Pg.1556]

The polarization dependence of the photon absorbance in metal surface systems also brings about the so-called surface selection rule, which states that only vibrational modes with dynamic moments having components perpendicular to the surface plane can be detected by RAIRS [22, 23 and 24]. This rule may in some instances limit the usefidness of the reflection tecluiique for adsorbate identification because of the reduction in the number of modes visible in the IR spectra, but more often becomes an advantage thanks to the simplification of the data. Furthenuore, the relative intensities of different vibrational modes can be used to estimate the orientation of the surface moieties. This has been particularly useful in the study of self-... [Pg.1782]

Differential cross-sections for particular final rotational states (f) of a particular vibrational state (v ) are usually smoothened by the moment expansion (M) in cosine functions mentioned in Eq, (38). Rotational state distributions for the final vibrational state v = 0 and 1 are presented in [88]. In each case, with or without GP results are shown. The peak position of the rotational state distribution for v = 0 is slightly left shifted due to the GP effect, on the contrary for v = 1, these peaks are at the same position. But both these figures clearly indicate that the absolute numbers in each case (with or without GP) are different. [Pg.64]


See other pages where Moments number is mentioned: [Pg.131]    [Pg.273]    [Pg.193]    [Pg.243]    [Pg.131]    [Pg.273]    [Pg.193]    [Pg.243]    [Pg.189]    [Pg.65]    [Pg.63]    [Pg.694]    [Pg.379]    [Pg.502]    [Pg.510]    [Pg.593]    [Pg.742]    [Pg.1061]    [Pg.1065]    [Pg.1321]    [Pg.1367]    [Pg.1469]    [Pg.1548]    [Pg.1569]    [Pg.1570]    [Pg.1781]    [Pg.2210]    [Pg.2440]    [Pg.2441]    [Pg.2998]   
See also in sourсe #XX -- [ Pg.104 ]




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