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Phase characteristic

Figure 5. Amplitude-phase characteristics of the model for visco-elasto-plastic (left column) and brittle (right column) materials 1- spectrum responses 2- TF models. Figure 5. Amplitude-phase characteristics of the model for visco-elasto-plastic (left column) and brittle (right column) materials 1- spectrum responses 2- TF models.
Excess phase. This is the point of closest approach of the phase characteristic to -360 degrees anytime the gain is greater than i (OdB). [Pg.205]

The concepts of interface rheology are derived from the rheology of three-dimensional phases. Characteristic for the interface rheology is the coupling of the motions of an interface with the flow processes in the bulk close to the interface. Thus, in interface rheology the shear and dilatational stresses of the interface are in equilibrium with the corresponding shear stress in the bulk. An important feature is the compressibility of the adsorption layer of an interface in contrast, the flow elements of the bulk are incompressible. As a result, compression or dilatation of the adsorption layer of a soluble surfactant is associated with desorption and adsorption processes by which the interface tends to reinstate the adsorption equilibrium with the bulk phase. [Pg.184]

After extraction, each phase may be studied independently in order to obtain a useful qualitative evaluation of the components in the original sample. The selectivity and specificity of fluorescence analysis can be especially beneficial in identification of PAHs. For example, some components could be identified by examining the fluorescence spectra of the organic and aqueous phases. Characteristic peak shapes may reveal identities of the components. For more complicated systems in which the spectra overlap, lifetime measurements may be used to identify components (27). [Pg.175]

Molecular properties and reactions are controlled by electrons in the molecules. Electrons had been thonght to be particles. Quantum mechanics showed that electrons have properties not only as particles but also as waves. A chemical theory is required to think abont the wave properties of electrons in molecules. These properties are well represented by orbitals, which contain the amplitude and phase characteristics of waves. This volume is a result of our attempt to establish a theory of chemistry in terms of orbitals — A Chemical Orbital Theory. [Pg.330]

Phase Characteristics Median Duration (with Treatment)... [Pg.1416]

In phase-fluorimetric oxygen sensors, active elements are excited with periodically modulated light, and changes in fluorescence phase characteristics are measured. The delay or emission (phase shift, ( ), measured in degrees angle) relates to the lifetime of the dye (x) and oxygen concentration as follows ... [Pg.504]

Vibration Diagram Method. In actuality the last cases above are not described accurately by this dipole array model because actual phases of the electric fields are significantly altered from those of linear waves. (A more realistic, but complex model is to consider amplitude and phase characteristics of the oscillating vertically polarized component of electric field resulting from rotation of a line of transverse dipoles of equal magnitude but rotated relative to each other along the line such that their vertical components at some reference time are depicted by Figure 2.) For this reason and to handle details of focused laser beams one must resort to a more mathematically based description. Fortunately, numerical... [Pg.39]

CEC is often inappropriately presented as a hybrid method that combines the capillary column format and electroosmotic flow employed in high-performance capillary electrophoresis with the use of a solid stationary phase and a separation mechanism, based on specific interactions of solutes with the stationary phase, characteristic of HPLC. Therefore CEC is most commonly implemented by means typical of both HPLC (packed columns) and CE (use of electrophoretic instrumentation). To date, both columns and instrumentation developed specifically for CEC remain scarce. [Pg.14]

Quantities useful for predicting phase continuity and inversion in a stirred, sheared, or mechanically blended two-phased system include the viscosities of phases 1 and 2, and and the volume fractions of phases 1 and 2, and ij. (Note These are phase characteristics, not necessarily polymer characteristics.) A theory was developed predicated on the assumption that the phase with the lower viscosity or higher volume fraction will tend to be the continuous phase and vice versa (23,27). An idealized line or region of dual phase continuity must be crossed if phase inversion occurs. Omitted from this theory are interfacial tension and shear rate. Actually, low shear rates are implicitly assumed. [Pg.238]

Assume that the volume of dense phase, the fraction solids in it, and the gas flow through it remain the same at all gas velocities, in which case, the lean phase alone expands and contracts to account for the variation in total volume of fluidized bed with change in gas flow rate. The dense-phase characteristics are given by the conditions at incipient fluidization. [Pg.171]

Mobile-Phase Characteristics in the Reversed-Phase Chromatography of... [Pg.588]

These drawbacks can be avoided to a large extent, using the voltammetry of microparticles—a technique involving solid state electrochemistry where down to about 10 to 10 mol of sample [74-78] can be transferred by abrasion into the surface of an inert electrode, usually paraffin-impregnated graphite electrodes, and the electrode is later immersed in a suitable electrolyte for recording its voltam-metric response. The response of this sample-modified electrode, consisting of the reduction or oxidation of the solid materials, becomes phase-characteristic. [Pg.41]

The Chebyshev filter offers higher attenuation and a steeper roll-off near the cutoff frequency than the Butterworth filter. There is a tradeoff to achieve the higher attenuation. The cost of utilizing a Chebyshev filter is higher values of Q, which leads to difficulties in hardware realization, and nonlinear phase characteristics, which can result in difficulties in predicting circuit performance. [Pg.52]

GAIN- PHASE CHARACTERISTICS OF THE POWER SUPPLY TEST BOARD USING STRF-6524... [Pg.109]

The speed of a chromatographic separation is fixed by the particle size, the stationary phase characteristics, the available pressure, the solvent viscosity, the solute diffusivity, the a values of the critical pair, and extracolumn dispersion. One way to achieve faster separations is to reduce the particle size of the stationary phase. However, if material of smaller diameter is packed into a conventional size column, the backpressure will become prohibitively high. Thus, in a compromise between speed and optimum performance, narrow (<2 mm) columns packed with small 3-5 ju.m diameter particles have been developed. [Pg.245]

Thus, there is no longer any dependence on any phase characteristics and all phase control would be lost. [Pg.106]

A simple variant of the COSY experiment is COSY-35 (sometimes called COSY-45), in which the second 90° pulse is reduced from a 90° pulse to a 35° or 45° pulse (Fig. B.3). The result is that the fine structure of crosspeaks is simplified, with half the number of peaks within the crosspeak. This makes it much easier to sort out the coupling patterns in both dimensions and to measure couplings (active and passive) from the crosspeak fine structure. A more important variant of the COSY experiment is the DQF (double-quantum filtered)— COSY (Fig. B.4), which adds a short delay and a third 90° pulse. The INEPT transfer is divided into two steps antiphase I spin SQC to I,S DQC, and I,S DQC to antiphase S spin SQC. The filter enforces the DQC state during the short delay between the second and third pulses either by phase cycling or with gradients. DQF-COSY spectra have better phase characteristics and weaker diagonal peaks than a simple COSY, so this has become the standard COSY experiment. [Pg.636]

Figure 7.20. Effects of temperature on phase and static order of the membrane bilayer. Reductions in temperature from the physiological temperature of the organism (cell), that is, temperatures near those of adaptation or acclimation, lead to formation of gel-phase regions, which may separate from lipids that remain in the liquid-crystalline phase, the phase characteristic of most of the bilayer at physiological temperatures. At sufficiently low temperatures, the bulk of the membrane phospholipids enter the gel phase. Figure 7.20. Effects of temperature on phase and static order of the membrane bilayer. Reductions in temperature from the physiological temperature of the organism (cell), that is, temperatures near those of adaptation or acclimation, lead to formation of gel-phase regions, which may separate from lipids that remain in the liquid-crystalline phase, the phase characteristic of most of the bilayer at physiological temperatures. At sufficiently low temperatures, the bulk of the membrane phospholipids enter the gel phase.
To determine torsion force constant and height of tip we didn t refer to cantilever passport parameters that can be significant varied. The value of kL we found used new the most precise method based on analyzing of amplitude-phase characteristic [to be published] but tip height was determined with the help of optical microscope. We got kL = 77.1 N/m ltip = 10 pm. [Pg.419]


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See also in sourсe #XX -- [ Pg.175 , Pg.227 ]




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Bicontinuous characteristics, phases

Bubble phase characteristics

Characteristic Time for Gas-Phase Diffusion to a Particle

Characteristic Time of Aqueous-Phase Diffusion in a Droplet

Characteristic solid phases

Characteristics of Liquid Crystal Phases

Characteristics of Liquid-Phase Sintering

Chiral stationary phases characteristics

Counterpart Phase Separation Characteristics of Metallic Alloys and Inorganic Glasses

HPLC mobile phases, characteristics

Liquid-phase adsorptions adsorbent characteristics

Liquid-phase adsorptions adsorptive characteristics

Material characteristics phases

Mobile phase characteristics

Nematic liquid crystal phase characteristics

Nonaqueous phase liquids characteristics

Ordered phases characteristics

Phase change materials characteristics

Phase characteristic features

Phase structure characteristics

Phase transitions characteristics

Reverse phase method development detection characteristics

Reversed-phase chromatography characteristics

Solid-phase extraction characteristics

Solid-phase microextraction characteristics

State variables and characteristic functions of a phase

Stationary phase characteristics

Supercritical fluid mobile phases characteristics

Thermal characteristics, phase transitions

Two-Phase Flow Characteristics

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