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Model Motion

The physieal signifieanee of the time independent wavefunetions and energies treated in Seetion II as well as the meaning of the seven fundamental points given above ean be further illustrated by again eonsidering the simple two-dimensional eleetronie motion model. [Pg.52]

In experimental measurements, sueh sharp 5-funetion peaks are, of eourse, not observed. Even when very narrow band width laser light sourees are used (i.e., for whieh g(co) is an extremely narrowly peaked funetion), speetral lines are found to possess finite widths. Let us now diseuss several sourees of line broadening, some of whieh will relate to deviations from the "unhindered" rotational motion model introdueed above. [Pg.429]

A time-and-motion modeling mind-set can easily blinker analysis of how best to improve the value created by research. Truly useful simulations of drug discovery must go beyond simplistic assumptions about yields at stage gates and address the causes of failure, starting to quantify the common concept of pipeline quality. ... [Pg.266]

Due to lack of understanding of the wave structure and motions, modeling of the interfacial shear remains empirical. [Pg.210]

Experimental mobility values, 1.2 X 10-2 cm2/v.s. for eam and 1.9 x 10-3 cm2/v.s. for eh, indicate a localized electron with a low-density first solvation layer. This, together with the temperature coefficient, is consistent with the semicontinuum models. Considering an effective radius given by the ground state wave-function, the absolute mobility calculated in a brownian motion model comes close to the experimental value. The activation energy for mobility, attributed to that of viscosity in this model, also is in fair agreement with experiment, although a little lower. [Pg.175]

To extend the integration time further, it is necessary to introduce acceleration into the target s motion model. The range to the target should now be expressed as r = ra + vat + a0t2/2. The matched filter concept now leads to the three-dimensional range-Doppler-velocity... [Pg.232]

For automotive applications with relative low velocities and a high update rate 1/T, a pure linear motion model with constant velocity can be considered. The respective state transition matrix A for a constant-velocity trajectory can be used to calculate the predicted target state vector for the next time step by the following equation ... [Pg.305]

Recent solid state NMR studies of liquid crystalline materials are surveyed. The review deals first with some background information in order to facilitate discussions on various NMR (13C, ll, 21 , I9F etc.) works to be followed. This includes the following spin Hamiltonians, spin relaxation theory, and a survey of recent solid state NMR methods (mainly 13C) for liquid crystals on the one hand, while on the other hand molecular ordering of mesogens and motional models for liquid crystals. NMR studies done since 1997 on both solutes and solvent molecules are discussed. For the latter, thermotropic and lyotropic liquid crystals are included with an emphasis on newly discovered liquid crystalline materials. For the solute studies, both small molecules and weakly ordered biomolecules are briefly surveyed. [Pg.68]

This approach yields spectral densities. Although it does not require assumptions about the correlation function and therefore is not subjected to the limitations intrinsic to the model-free approach, obtaining information about protein dynamics by this method is no more straightforward, because it involves a similar problem of the physical (protein-relevant) interpretation of the information encoded in the form of SD, and is complicated by the lack of separation of overall and local motions. To characterize protein dynamics in terms of more palpable parameters, the spectral densities will then have to be analyzed in terms of model-free parameters or specific motional models derived e.g. from molecular dynamics simulations. The SD method can be extremely helpful in situations when no assumption about correlation function of the overall motion can be made (e.g. protein interaction and association, anisotropic overall motion, etc. see e.g. Ref. [39] or, for the determination of the 15N CSA tensor from relaxation data, Ref. [27]). [Pg.290]

The derivation of the SD or model-free parameters is just the beginning of the analysis of protein dynamics what one finally wants to achieve is a picture of protein dynamics in terms of motional models. [Pg.301]

The validity of this analysis rests on the absence of any hypothesis regarding the motional model and/or the nature of the interactions. Also, it is especially reassuring to find for (Xc), values close to what is expected for protein reorientation (53). [Pg.38]

Correlation Times for Backbone and Side-Chain Motions in Poly(but-1-ene sulfone) of P = 700 as a 25% w/v Solution in Chloroform-d, Deduced from the Simple Isotropic Single-T Motional Model... [Pg.24]

Figure 3. Plausible mechanism for the conversion of D-ribulose-5-phosphate isomerase to n-arabinose-5-phosphate by n-arabinose-5-phosphate isomerase. It is a least-motion model consistent with the mechanisms of similar enzymes (21-23). Figure 3. Plausible mechanism for the conversion of D-ribulose-5-phosphate isomerase to n-arabinose-5-phosphate by n-arabinose-5-phosphate isomerase. It is a least-motion model consistent with the mechanisms of similar enzymes (21-23).
Without using any motional model, the temperature positions of T and Tip minima can be assigned an appropriate frequency 90 MHz at 120 °C from Ti and 43 kHz at - 34 °C from T r These two results fit quite well on the relaxation map of BPA-PC obtained from dynamic mechanical and dielectric relaxation. They support the fact that phenyl ring motions are involved in the /3 relaxation of BPA-PC. Furthermore, the Ti and T f> data can be simulated by considering the Williams-Watts fractional correlation function [33] ... [Pg.75]

First, it is worth noting that the activation energy value derived from the 22.6 MHz data strongly depends on the motional model considered. Thus, with a two-site jr-flip jump model, leading to a single exponential correla-... [Pg.83]

A motional model is required in order to interpret, in terms of motions, the change as a function of temperature of either the chemical shift anisotropy or ti/2. An approach similar to the one applied to PET has been adopted for Ar-Al-PA [58], leading to the following model for the phenyl rings ... [Pg.118]

In this discussion, we have considered a molecular motion that includes two independent motions in order to explain qualitatively the fact that two noncrystalline phase involve the same Tic and different T2c s. To analyze these phenomena more quantitatively, we have to evaluate Tic and T2C theoretically, assuming an adequate motional model. Refer to our article Murayama K, Horii F, Kitamaru R (1983) Bull Inst Chem Res, Kyoto Univ, 61 299... [Pg.100]

This paper presents the first experimental results for the solid motion inside a pilot-scale rotary kiln. Such data are useful to enable efficient pyrolysis reactions inside a rotary kiln to be carried out, through the prediction of residence time and material hold-up, and the evaluation of different surfaces and temperature profiles according to the operating conditions. In the first part, the pilot-scale rotary kiln and the principle of the experiments will be described. An original dynamic solid motion model will be presented in the second part, this dynamic model is derived from the original static model of Seaman [1], The static and dynamic experimental results are finally compared with the simulated results. [Pg.316]

In addition to the semiquantitative approach, more quantitative analytical approaches have been reported. For example, in the fast motion regime (t 10 11—10 9 s at X-band), one can compute the nitroxide rotational correlation time based on the measured line-widths and amplitudes (Marsh, 1981 Qin et al., 2001 Xi et al., 2008). Furthermore, it is possible to simulate a nitroxide spectrum based on quantum mechanics and specific motional models (Columbus et al., 2001 Grant et al., 2009 Hustedt et al., 1993 Liang et al., 2000 Qin et al., 2006 Schneider and Freed, 1989). The details of these advanced analysis techniques are not discussed here, interested readers are instead referred to a recent review (Sowa and Qin, 2008) and the relevant literatures. [Pg.320]

FIG. 7.—Hall-Weber-Helfand (HWH) motional model. A[Pg.81]

Several attempts have been made to interpret the relaxation data of polysaccharides by employing a variety of dynamic models suitable for local chain motions of synthetic polymers. One motional model that has been applied to polysaccharides133135136 is the log 2) model72 (Eq. A-6 in the Appendix), which assumes that isotropic reorientation is characterized by a skewed distribution of correlation times, with tails toward longer correlation times (Fig. 13). The distribution func-... [Pg.117]


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Brownian motion Langevin model

Brownian motion Ohmic model temperature

Brownian motion continuous-time random walk model

Brownian motion friction model

Brownian motion itinerant oscillator models

Brownian motion model

Brownian motion phenomenological modeling

Fibre motion model

Fishing for Functional Motions with Elastic Network Models

Internal motion model

Ionic motion channel model

Jump model, three-bond, phenyl group motion simulation

Model Solutions for the Motion of a Hypothetical Economy in Ideal Time

Model motional

Model motional

Model protein machines motion produced

Model systems nuclear motion

Modeling large-scale motions

Models of Internal Motions

Models rotational motion

Models translational motion

Models vibrational motion

Molecular modelling polymer motion

Motion model protein machines

Motion synthetic model protein

Processes Motional Models

Reptation Model of Molecular Motion

Reptation model segmental motion

Rouse model tube motion

Simple Models of Motions

The Weak Coupling Limit Brownian Motion Model and Universality

The parton model including transverse motion

Three-bond jump model, motion

Turbulent motion model

Weber-Helfand model, motion

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