Comparison between static measurements

Arabosse, P., Rodier, E., Ferrasse, J.H., Chavez, S., and Lecomte, D. 2003. Comparison between static and dynamic methods for sorption isotherm measurements. Drying Technol. 21, 479-497. 

The evaporation path shown in Fig. 10 is very close to a straight line owing to the low vapor pressure of phenethyl alcohol. At first the structural changes during evaporation will be described followed by a comparison between the measured vapor pressures and those estimated from the static ones. 

The result of investigations up to 10 load cycles show that for glass fiber reinforced plastics, the ductile matrix systems EP2 and EP3 are superior to iaminates with the brittle EPl system. Eor glass fiber reinforced piastics, Pig. 4.94, ieft shows the comparison between static strength and the cyclic strengths measured in singie-step tests. 

From equations 13 16, the standard error for each measurement as a function of the elution time can be obtained. Additional propagation of these errors through the Integration across the chromatogram results in estimates of the errors associated with the SEC calculation of the average polymer properties. Therefore, it enables reliable statistical comparisons between SEC estimates and static measurements... 

Measurement of the cyclone pressure drop of different operating temperature was carried out for temperature ranging from 293 to 1123 K by Bohnet [2]. The comparison between the Bohnet experiment, empirical model and CFD prediction is shown in Figs. 7 and 8. Fig. 9 shows the three-dimension map of static pressure for operating temperature of 950 K. 

A number of studies have attempted to characterize ionic liquids through their dielectric constant, and all have observed inconsistencies between the measured dielectric constant and the solvation properties of the liquid. Recent experiments making use of dielectric reflectance spectroscopy [214] indicate dielectric constants in the range of 10-15 for a series of imidazolium-based ILs, substantially lower than those for molecular solvents observed to possess comparable polarities as estimated by solvatochromism. Weingartner [215] has recently published a series of static dielectric constants obtained from dielectric reflectance spectroscopy, and compared them with those of common molecular liquids. The analysis includes comparison with the Kamlet-Taft ji parameter for the liquids from Eq. (11) we have prepared a plot of n versus dielectric constant in Fig. 6. The relationship between n and e for molecular liquids... 

Figure 7.5 shows a comparison of the static and cyclic crack velocities for the alumina/SiC composite, similar to that illustrated in Fig. 7.2 for alumina. As seen for monolithic alumina, the ceramic composite undergoes slower rates of fracture when (1) fluctuations are introduced in the tensile loads and (2) the cyclic frequency is raised. The differences between static and cyclic crack growth rates are maximum at the lower Kmax levels. As in the case of unreinforced alumina, crack velocities estimated for cyclic loads on the basis of sustained load crack growth data (assuming identical failure mechanisms) are higher than those measured experimentally. 

A comparison between pulsed flow and conventional pulsed static calorimetry techniques for characterizing surface acidity using base probe molecule adsorption has been performed by Brown and coworkers [20, 21]. In a flow experiment, both reversible and irreversible probe adsorption occurring for each dose can be measured, and the composition of the gas flow gas can be easily modified. The AHads versus coverage profiles obtained from the two techniques were found to be comparable. The results were interpreted in terms of the extent to which NH3 adsorption on the catalyst surface is under thermodynamic control in the two methods. 

A comparison of ISLS experimental data and Cheetah computational results is given in Figure 12. The exp-6 potential model used was based on the shock Hugoniot of methanol. The 3% difference between data sets shows the utility of Cheetah and the consistency between static and dynamic equation of state measurements. The exp-6 parameters for species considered here are given in Table 11. 

It is necessary to remark that a large number of comparisons between experimental and theoretical results for microchannels have revealed a deep mismatch in the thermal boundary and inlet conditions that can preclude the use of the conventional correlations. In addition, in experiments on flow and heat transfer in microchannels, some parameters, like the channel dimensions, the average roughness, the local convective heat transfer, the local value of the static pressure along a microchannel, and so on, are difficult to measure accurately. For this reason, a large number of inconsistencies in published data are very likely to be due to experimental inaccuracies. 

An interesting comparison exists between static and cyclic fatigues for Ce-TZP, in which, as is known, a t m transformation takes place. Figure 7.16 shows a comparison of the measured results of static and cyclic fatigue tests for three Ce-TZP materials. The time-to-failure of the statically-loaded specimens is longer... 

Photographs of the channel were taken every 5 seconds. A comparison between the experimental results and the present model is shown in Figure 1.17. We observe that the yj t law fits well the experiments, with the constant value of the static contact angle. A small overshoot is observed but it is not significant. It is within the error margin of the uncertainties of measurement of the surface tension, viscosity and contact angle. 

A quantitative comparison between the prediction derived from the yield stress equation and the experimental results was made by Hao for the zeolite/silicone oil system [29J. The static dielectric constant of the pure zeolite material and the yield stress of zeolite/silicone oil suspension of the particle volume fraction 0.23 were experimentally measured at different temperatures. The calculated yield stress values from Eq. (69) vs. temperature is shown in Figure 17 as a solid line. For comparison, the experimentally measured data are also shown in Figure 17 as black points. As wc can sec, the predicted values agree very well with the experimental ones, indicating that Eq. (69) is able to predict the yield stress of ER fluids, indeed. 

In light of the abnormal behavior of ultrasound velocity and attenuation near the SmA-SmC transition [70, 71], Benguigui and Martinoty [72] advanced a theory to explain the experimental data. They concluded that the Ginzburg crossover parameter Gq) determined by the static properties, (e.g. heat capacity) could be much smaller than that obtained from the measurement of the elastic constant. However, a quantitative comparison between the theoretical prediction and the experimental data is still lacking. 

However, it was found that the obtained values are lower than the modulus obtained from quasi-static measurements, indicating that a direct comparison between the results from both techniques is not straightforward. A weak tendency of increasing E with increasing HA content is seen up to 20% ceramic content. As observed before, this formulation also optimised the ultimate strength, being in principle the material with better mechanical performance. 

This chapter focuses on the elastic properties of the NEs deduced from shear mechanical measurements. As the comparison between the theoretical descriptions and the experimental results have led to considerable controversies (Martinoty et al. 2004a, b, c Terentjev and Warner 2004 Stenull and Lubensky 2004) it is useful to understand the evolution of the topic in order to make a brief historical presentation of the various static and dynamic theories—conventional linear elastic theory, soft elasticity (original version), soft elasticity (version 2), bifurcation-type theory—which were progressively introduced for describing the elastic properties of these materials. 

Figure 15.15 Comparison between experimental and calculated transformed volume fractions. The experimental values are deduced from light intensity measurements. The calculations are performed in two cases without (static) or with elongation effect [65].

Carbon monoxide chemisorption was used to estimate the surface area of metallic iron after reduction. The quantity of CO chemisorbed was determined [6J by taking the difference between the volumes adsorbed in two isotherms at 195 K where there had been an intervening evacuation for at least 30 min to remove the physical adsorption. Whilst aware of its arbitrariness, we have followed earlier workers [6,10,11] in assuming a stoichiometry of Fe CO = 2.1 to estimate and compare the surface areas of metallic iron in our catalysts. As a second index for this comparison we used reactive N2O adsorption, N20(g) N2(g) + O(ads), the method widely applied for supported copper [12]. However, in view of the greater reactivity of iron, measurements were made at ambient temperature and p = 20 Torr, using a static system. 

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