Weber method

A. L. Stacy and R. B. Weber. Method for reducing deleterious environmental impact of subterranean fractumg processes. Patent US 5424285, 1995. 

The Weber method provides parameters characteristic of the environment of the rotating unit such as the limiting anisotropy and the thermal coefficient to resistance to a rotation. Also, the method permits to separate the motion of different classes of fluorophore. 

When a protein contains fluorophore residues located at the surface and in the core as it is the case for a j-acid glycoprotein, the results obtained from the classical Perrin plot contain contributions from all residues. In order to obtain information on the motion of each class of fluorophore residues, one may follow anisotropy and intensity variations as a function of quencher concentration (Quenching Resolved Emission Anisotropy) or / and anisotropy and lifetime variations with temperature (-50 to +35°C) (Weber method). 

Table 8.6. Anisotropies (A) and the fractional resistance to a rotation (ft) of Trp residues of ap acid glycoprotein measured with the Weber method in absence and presence of progesterone ...

The anisotropies of both Trp-residues of apacid glycoprotein measured at 20°C are very close (Table 8.7), (a result identical to that obtained with the Weber method, see Table 8.6) indicating that the two Trp residues are highly mobile. This result is confirmed by the values of the rotational correlation times (3 and 5 ns) lower than the global rotational correlation time of a i-acid glycoprotein. When the Trp residue is embedded in the protein core and does not show any residual motions such as in the Lens culinaris agglutinin, its rotational con elation time will be close to that of the protein and its anisotropy will be higher than that of the surface Trp residue. 

We notice however, that the anisotropies are more important in the Weber method. This can be explained by the fact that in the Weber method, anisotropies were calculated at low temperatures (-33 and -16°C for the buried and surface Trp residues, respectively), while in the QREA method, the anisotropies were measured at 20°C. At low temperatures, the global rotation of the protein and the local motions ai ound the Trp residues are decreased. 

Although we haye shown that the three Trp-residues contribute to the global fluorescence of a i-acid glycoprotein (paragraph 5 c of this chapter) quenching resolved emission anisotropy and the Weber method allowed giving a description on the mean local dynamic of the Trp-residues. The dynamic of the surface Trp residue is well separated from the two other Trp residues. 

H. P. Weber, Method for pulsewidth measurement of ultrashort light pulses, using nonlinear optics. J. Appl. Phys. 38, 2231 (1967)... 

Weber, P. L. Buck, D. R. Capillary Electrophoresis A Past and Simple Method for the Determination of the Amino Acid Composition of Proteins, /. Chem. Educ. 1994, 71, 609-612. This experiment describes a method for determining the amino acid composition of cyctochrome c and lysozyme. The proteins are hydrolyzed in acid, and an internal standard of a-aminoadipic acid is added. Derivatization with naphthalene-2,3-dicarboxaldehyde gives derivatives that absorb at 420 nm. Separation is by MEKC using a buffer solution of 50 mM SDS in 20 mM sodium borate. 

J. B. Weber and co-workers, in N. D. Camper, ed.. Research Methods in Weed Science, Southern Weed Science Society, Champaign, lU. 1986, pp. 

D. Seebach, R. Imwinkelried, and T. Weber, EPC Synthesis With C,C Bond Formation via Acetals and Enimines, in Modern Synthetic Methods 1986, Vol. 4, R. Scheffold, Ed., Springer-Verlag, New York, 1986, p. 125. 

Weber, M. A. and Penny, R. K. 1991 Probabilistic Stress Analysis Methods. Stress Analysis and Failure Prevention, DE-Vol. 30, ASME, 21-27. 

Thermodynamic properties. A molecular-dynamics simulation method (using a steepest decent method) with Stillinger-Weber potential is employed to optimize structures and to obtain the cohesive en-... 

The force /) , was obtained with the aid of the virtual power method by assuming that the floating power arises only from the force /) ,. This kind of approach has been used by Weber. ... 

Modeling of the force was actually based on the force balance of a single solid particle extending the result to cover a larger set of solid particles, we obtained Eq. (14.105). This method of modeling is adequate for a homogeneous flow where the particles move separately, not as a new kind of solid-phase structure. Weber has written the friction force in the form... 

A full-scale treatment of crystal growth, however, requires methods adapted for larger scales on top of these quantum-mechanical methods, such as effective potential methods like the embedded atom method (EAM) [11] or Stillinger-Weber potentials [10] with three-body forces necessary. The potentials are obtained from quantum mechanical calculations and then used in Monte Carlo or molecular dynamics methods, to be discussed below. 

With a computer program, which solved Eqs. (5) and (7) for We by numerical method, Weber numbers were obtained from layer to layer for each injection molding operation. The calculated points were then connected to curves, depending on the normalized thickness. Figure 17 shows these theoretically deduced Weix)... 

This method of fixing the derived unit by making the arbitrary constant equal to unity was largely extended by Gauss and Weber. 

The salts were identified by their metallic content, which was detd by standard lab methods. Their expln temps were detd by the method originated by H. Weber (Bull US Bureau of Standards 9, 119 (1913) and modified at PicArsn [PATR 1401 (1944)]. The sensitivity to impact was detd using the PicArsn app, described by H.S. Deck [ArmyOrdn 7, 34 (1926)], using a 2 kg wt... 

Jablonski (48-49) developed a theory in 1935 in which he presented the now standard Jablonski diagram" of singlet and triplet state energy levels that is used to explain excitation and emission processes in luminescence. He also related the fluorescence lifetimes of the perpendicular and parallel polarization components of emission to the fluorophore emission lifetime and rate of rotation. In the same year, Szymanowski (50) measured apparent lifetimes for the perpendicular and parallel polarization components of fluorescein in viscous solutions with a phase fluorometer. It was shown later by Spencer and Weber (51) that phase shift methods do not give correct values for polarized lifetimes because the theory does not include the dependence on modulation frequency. 

Measurements of tan A as a function of temperature for the six humic fractions are plotted in Figures 2a-f. These measurements were made at pH 6.5. These plots show a maximum between 6 °C emd 25 °C. Equation 15 offers another method for the calcuation of the molar volume based on the emisotropy of the molecule and the temperature and viscosity at the experimental maximum of the tan A plots. The consequences of obtaining the volume in this manner are discussed by Mantulin and Weber U8J. 

In practice, uniform films are obtained for only a limited number of film-substrate material combinations (17). The more common experience is that the deposited material forms 3D clusters. The clusters may form directly on the bare substrate, in the Volmer-Weber growth mode, or on top of a very thin but uniform film of the deposit, the Stranski-Krastanov growth mode. We now discuss a method for determining the equilibrium configuration of the deposited material. 

Chan, T. (1984). in Numerical Methods for Bifurcation Problems, T. Kup-per, H. Mittelmann and H. Weber, Eds., Birkhauser Verlag, Basel. 

Weber, L., Illgen, K., Almstetter, M. (1999) Discovery of New Multi-Component Reactions with Combinatorial Methods. Synlett, 366-374. 

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