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Factorization approximation

Effectiveness factor approximation by using a perturbation method... [Pg.705]

The average value of the transfer factor (approximately 2300 cm2/hr) derived from all data in our study differs somewhat from the transfer factor of 3300 cm2/hr observed in a preceding study during the cultivation of carnations (Brouwer et al., 1992). However, that transfer factor had been derived from data on both high-volume spray (as in the present study) and dusting operations. The powder formulations showed an effective transfer of the residue to the body. Recalculated transfer factors for only high-volume applications showed an average of approximately 2500 cm2/hr. [Pg.134]

Figure 1. Enzymes bind the transition state (ES) more tightly than the ground state (ES) by a factor approximately equal to the rate of acceleration... Figure 1. Enzymes bind the transition state (ES) more tightly than the ground state (ES) by a factor approximately equal to the rate of acceleration...
In order to assign more IR signals of 4a, ab initio calculations on Hbdmpza (3b) and 4a were performed. It is well known for the chosen HF/6-31G basis set that calculated harmonical vibrational frequencies are typically overestimated compared to experimental data. These errors arise from the neglecting anharmonicity effects, incomplete incorporation of electron correlation and the use of finite basis sets in the theoretical treatment (89). In order to achieve a correlation with observed spectra a scaling factor (approximately 0.84-0.90) has to be applied (90). The calculations were calibrated on the asymmetric carboxylate Vasym at 1653 cm. We were especially interested in... [Pg.115]

The Q-factor approximation method (16) was an early attempt at extending the application of the peak position method to polymers of different chemical types than the calibration standards. [Pg.76]

The purpose of this study was to evaluate the linear calibration technique employing a single polydisperse standard and the search algorithm described above for non-aqueous and aqueous SEC. Comparison of this calibration technique to peak position, universal calibration, and Q-factor approximation techniques which make use of a series of narrow MWD polystyrene standards was also carried out. [Pg.77]

Table VI lists the results of this study of calculated molecular weight accuracy as a function of calibration method with the PVC poljnners. A PVC polymer sample was analyzed and molecular weight averages were calculated by means of each calibration method. All SEC peak processing parameters used for calculation of MWD values were held constant. As shown in Table VI, the universal calibration method provided a somewhat more accurate value than the Q-factor approximation method or the linear, poly-disperse standard method. Table VI lists the results of this study of calculated molecular weight accuracy as a function of calibration method with the PVC poljnners. A PVC polymer sample was analyzed and molecular weight averages were calculated by means of each calibration method. All SEC peak processing parameters used for calculation of MWD values were held constant. As shown in Table VI, the universal calibration method provided a somewhat more accurate value than the Q-factor approximation method or the linear, poly-disperse standard method.
A comparison to calculated molecular weight accuracy with peak position, universal calibration, and Q-factor approximation methods using a series of narrow MWD standards was performed. [Pg.93]

Spectra and Bonding in Metal Carbonyls The secular equations in the energy factored approximation are, for M(CO)5L,... [Pg.11]

For the determination of energy factored parameters, full isotopic substitution is bound to be useless. This is because, in the energy factored approximation, such substitution is predicted to multiply each frequency by a factor of [fij/j, ), where fx is the reduced mass mcfnol[nic+ o] of carbon monoxide, independent of the values of the parameters concerned. However, a great deal of information can be obtained from the spectra of partially substituted species, for which the Teller-Redlich product rule takes the particularly simple form... [Pg.14]

There is reason to believe that the rate of addition of oxygen atoms to olefins and the position of addition (orientation) are not governed by the same factors. In the case of 2-pentene the addition takes place at the doubly bonded carbon atom to which the CH3 group is attached and not to the one where the C2HB group is attached. At the same time the rates of addition to propylene and to 1-butene are the same and in both cases terminal addition occurs. Similarly, the rates of addition to 2-butene and 2-pentene are also about the same. If the rates of addition and the orientation were determined by the same factors, approximately equal addition at the two double bond C-atoms would be expected. Since this is not the case, it appears reasonable to conclude that the transition state which determines the rates of addition occurs quite early in the reaction process, before oxygen atoms become localized on either of the two double bond C-atoms. [Pg.146]

From these experiments, in which the range of catalyst-particle diameter (from 10-mm. pellets to crushed pellets of 2 to 4 mm. width and about 1 mm. height) has been changed by a factor approximating ten, the following can be concluded ... [Pg.263]

The total differential scatter cross-section is often written in the form factor approximation as a product of three factors describing three levels, electron, atom and molecule, of complexity of the scattering system ... [Pg.210]

An elongational or extensional viscosity (%) develops as a result of a conformational transition when disperse systems are forced through constrictions, or compressed or stretched (Kulicke and Haas, 1984 Rinaudo, 1988 Barnes et al., 1989 Odell et al., 1989 Clark, 1992). The intuitive logic is that the random coils resist the initial distortion. % is believed to elicit the human sensation of stringiness (Clark, 1995). If shear viscosity is denoted iq, rheologists define a Trouton ratio as %/ti, wherein % > T) by a factor approximating 3 for uniaxial extension and 6 for biaxial extension. Alternatively stated, the Newtonian ly calculates to one-third to one-sixth % (Steffe, 1992). [Pg.16]

We now discuss the second effect. Assuming a one sided diode, the dark current is inversely proportional to the diffusion length. Using the calculated values of the diffusion length under illumination, the calculated dark current is shown in Fig. 5.28. At 50 suns the dark current decreases by a factor approximately 16. Using the equation,... [Pg.132]

It may be noticed that by virtue of being a dressed Hamiltonian including the effect of correlation, diagrams 37-39 account for some of the CIS(D)-type correlation corrections (22-24) to CIS (diagrams 35 and 36). There is no need to make ad hoc adjustments to diagrams to ensure size correctness because diagram 37 (unlinked) cancels exactly between the ground and excited states. In other words, P-EOM-MBPT(2) has the factorization approximation built in. [Pg.33]

Transmission of HBV occurs sexually, parenteraUy, and perinataHy. In the United States, transmission occurs predominantly through sexual contact or injection-drug use. International travel is also an important risk factor. Approximately 20% of patients with chronic HBV infection develop complications of decompensated cirrhosis, including hepatic insufficiency and portal hypertension. HBV is a risk factor for development of hepatocellular carcinoma. [Pg.275]

The temperature dependenee of the electron transfer rate is dominated by the exponential factor in equation 3, and for most values of AG it will show an Arrhenius-like behaviour with an activation energy AG of (AG + X) lAX. However, when the exponential factor approximates to zero as the magnitude of X approaches that of nAG, the eleetron transfer rate will show a reverse temperature dependence determined by the pre-exponential factor in equation 3. This reverse temperature dependence can be understood by considering that raising the temperature will decrease the probability that the system is in the lowest nuclear configuration that is most favourable for the electron transfer reaction. [Pg.638]

After averaging Eq.( 10) over the heat bath variables with the aid of the Uouville space Feynman diagram (shown in Fig. 1) within the factorization approximation, the main term for the CARS process is given as... [Pg.171]

The effective absorption and stripping factors approximately in each zone are... [Pg.423]

The possible errors for ZAF correction in the analysis will be amplified for light elements (Z < 10), because in theoretical calculations of (ZiAiFi) factors, approximations that are valid... [Pg.194]

If N is equal to Avogadro s number, the single-sector distribution (11) will contain an overwhelmingly dominating factor approximately equal to... [Pg.41]


See other pages where Factorization approximation is mentioned: [Pg.51]    [Pg.308]    [Pg.81]    [Pg.13]    [Pg.295]    [Pg.238]    [Pg.78]    [Pg.84]    [Pg.72]    [Pg.52]    [Pg.3]    [Pg.5]    [Pg.7]    [Pg.75]    [Pg.268]    [Pg.177]    [Pg.894]    [Pg.239]    [Pg.732]    [Pg.76]    [Pg.347]    [Pg.57]   
See also in sourсe #XX -- [ Pg.183 ]




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Approximate Energy Unit Conversion Factors

Approximate conversion factors

Approximate factorization implicit

Approximate factorization implicit methods

Approximation form-factor

Approximation of the Effectiveness Factor for Bimolecular Reactions

Approximation photokinetic factor

Damping factor approximation

Effectiveness factor generalized approximations

Harmonic approximation scaling factors

Rotating wave approximation rotation factor

Structure Factor within Mean Field Approximation

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