Static experiments

Static experiments with pistonlike filtering can be reliable, however, to obtain information on the fluid loss behavior in certain stages of a cementation process, in particular when the slurry is at rest. 

The result is shown in Fig. 62 where the different Dc values, obtained from separate fits at each concentration, are also presented. The dynamic correlation length (c)/A = (3.4 + 0.7) c 067 005 is of the same order of magnitude as the value obtained from a static experiment on the PS/d-cyclohexane system [104]. The exponents for the concentration dependence of Dc and (c) are in agreement... 

The gas-phase reaction has been studied using static reaction systems12-13, flow reactors10, u> 14,15 and, more recently, using the shock-tube technique16,17. The decomposition was followed in static experiments both measuring the... 

Static experiments have been performed for radiolabeled surfactants [42,63], with microorganisms [8] or contaminated sediment exposure [64], since continuous assays are difficult, expensive (large amount of radiolabeled chemical needed) and restrictive (due to safety regulations) to perform. To avoid surfactant depletion in water, the exposure times are shorter, 15 h [26] or 24 h [12,24], but are valid for determining the BCF when the steady state is reached [8], and the actual exposure concentration (not the nominal) is used. 

Static experiments approach the situation described in Figure 2b. The appropriate boundary conditions are set and Laplace transformation performed by Bird et al. (16). Differentiation of their equations, evaluation at x = 0, and substitution in Fick s first law will provide the mass transfer rate at the interface. Diffu-sivities in the matrix and in water can also be derived. 

Experimental data supported by first- 39 principles calculations. A small CSA contribution was calculated and detected using static experiments with the deuterated compound, Mg(OD)2. 

Measurements can be made either statically or dynamically and selective gases like CO (or H2) can be used. In the static experiment, a known amount of gas is added to a known amount of metal catalyst. Each gas molecule takes up a specific area on the metal surface (typically the gas is not adsorbed on the inert support surface). In the dynamic experiment, gas is pulsed over a catalyst. The amount of gas remaining in the pulse after contact with the metal is measured and, as before, the gas on the metal surface is calculated by difference to estimate the surface area available for catalysis. 

Model Predictions. The rate for desorption of americium from the fissure surfaces into solution was assumed to equal the rate for the adsorption of americium from solution by the fissure surfaces. The sorption rate and the equilibrium fractionation of americium that were determined in the static experiments were used to determine input parameters to the ARDISC model. The ARDISC model predictions for the distributions of americium on the fissure surfaces in both sets of experiments are presented in Figures 5 through 10 along with the autoradiographs and the experimental histograms representing the various distributions of americium on the fissure surfaces. 

Vegetable staticks or, An account of some statical experiments on the sap in vegetables, London, 1727-33, 2 vols. Vol. II has title, Statical essays. 

The mass fraction Gi of the mass velocity M differs from the mass fraction of the local mixture when diffusion is taking place. Ki is the ordinary reaction rate of chemical kinetics, expressed as mole/unit volume/unit time, which is measured in a static experiment as a function of temperature and composition if the flame is in local thermal equilibrium. If not, this equation serves only as a measure of the nonequilibrium local reaction rate. 

A number of analogous compounds to BA have been reported, including 5,5 -dibenzo-[a]-pyrenyl (BBPY) [116]. These compounds exhibit emission spectra similar to BA. It would be interesting to explore the ultrafast dynamics of BBPY in order to test the generality of the GLE model. It would also be interesting to study the femtosecond dynamics of BA as a function of applied pressure. Static experiments on the emission of BA, reported by Hara et al. [123], demonstrate that in low viscosity solvents an increase of pressure affects the emission similarly to an increase of solvent polarity. As the pressure is increased, however, the LE/CT interconversion is slowed down. It would be interesting to measure C(r) in these environments and compare the solvation dynamics with LE/CT dynamics, in order to test the generality of the GLE dielectric friction model. 

So far, the experiments were concerned with static experiments. Looking at the dynamics of the field effects, valuable information can be obtained concerning the viscous properties of the polymers. For the orientation effect of the l.c. discussed before, the deformation of the l.c. requires time from the former to the new equilibrium state, if the voltage V > is applied. This response time ton depends in a first... 

Thus a measurement of the ultrasonic properties can provide valuable information about the bulk physical properties of a material. The elastic modulus and density of a material measured in an ultrasonic experiment are generally complex and frequency dependent and may have values which are significantly different from the same quantities measured in a static experiment. For materials where the attenuation is not large (i.e., a ca/c) the difference is negligible and can usually be ignored. This is true for most homogeneous materials encountered in the food industry, e.g., water, oils, solutions. 

Whatever the selected method (static, monotonous, or dynamic), it gives access to a limited range of timescales. For example it is almost impossible to perform static experiments in times less than 1 s, or dynamic tests at frequencies lower than 10 1 Hz, or tensile tests at strain rates higher than 103 s-1. These timescales are, however, indirectly accessible because the polymers generally obey a time-temperature superposition principle ... 

The ductile-brittle transition is clearly related to the yielding behavior of the thermoset in static experiments, (see Fig. 12.5). 

Angberg M, Nystrom C, Cartensson S. Evaluation of heat-conduction microcalorimetry in pharmaceutical stability studies I. Precision and accuracy for static experiments in glass vials. Acta Pharm Suec 1988 25 307-320. 

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