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ANALYSIS OF THE EXPERIMENTAL RESULTS

On the basis of kinetic data, a rate equation can be designed and even—if one is lucky— the reaction mechanisms can be determined at the molecular level. The result is thus a [Pg.5]


Consistent Data-Recording Procedures. Clear procedures for recording all pertinent data from the experiment must be developed and documented, and unambiguous data recording forms estabUshed. These should include provisions not only for recording the values of the measured responses and the desired experimental conditions, but also the conditions that resulted, if these differ from those plaimed. It is generally preferable to use the values of the actual conditions in the statistical analysis of the experimental results. For example, if a test was supposed to have been conducted at 150°C but was mn at 148.3°C, the actual temperature would be used in the analysis. In experimentation with industrial processes, process equiUbrium should be reached before the responses are measured. This is particularly important when complex chemical reactions are involved. [Pg.522]

Catalysts with Pd deposited on various supports such as Zr02 or mixed supports such as Al203-Zr02-Ba0 have been used for the elimination of NOx. Their activity in the presence of complex mixtures like CO-NO-O2-C3H5-CO2-H2O is better than that of Pd/Al203. This increase in activity is due not to a modification of the electronic properties of Pd but to a direct participation of the support in the process From the analysis of the experimental results, a biflinctional mechanism is proposed and discussed. [Pg.345]

Recently, Razumovskid441 studied the shape of drops, and satellite droplets formed by forced capillary breakup of a liquid jet. On the basis of an instability analysis, Teng et al.[442] derived a simple equation for the prediction of droplet size from the breakup of cylindrical liquid jets at low-velocities. The equation correlates droplet size to a modified Ohnesorge number, and is applicable to both liquid-in-liquid, and liquid-in-gas jets of Newtonian or non-Newtonian fluids. Yamane et al.[439] measured Sauter mean diameter, and air-entrainment characteristics of non-evaporating unsteady dense sprays by means of an image analysis technique which uses an instantaneous shadow picture of the spray and amount of injected fuel. Influences of injection pressure and ambient gas density on the Sauter mean diameter and air entrainment were investigated parametrically. An empirical equation for the Sauter mean diameter was proposed based on a dimensionless analysis of the experimental results. It was indicated that the Sauter mean diameter decreases with an increase in injection pressure and a decrease in ambient gas density. It was also shown that the air-entrainment characteristics can be predicted from the quasi-steady jet theory. [Pg.257]

Stop-flow experiments have been performed in order to study the kinetics of micellization, as illustrated by the work of Tuzar and coworkers on PS-PB diblocks and the parent PS-PB-PS triblocks [63]. In these experiments, the block copolymers are initially dissolved as unimers in a nonselective mixed solvent. The composition of the mixed solvent is then changed in order to trigger micellization, and the scattered light intensity is recorded as a function of time. The experiment is repeated in the reverse order, i.e., starting from the block copolymer micelles that are then disassembled by a change in the mixed solvent composition. The analysis of the experimental results revealed two distinct processes assigned as unimer-micelle equilibration at constant micelle concentration (fast process) and association-dissociation equilibration, accompanied by changes in micellar concentration (slow process). [Pg.93]

The discussion of the mechanisms and models of the relaxation process given in Section 2.5 shows that the application of time-resolved methods produces substantial advantages in accessing dynamical information, but it does not allow the complete pattern of the dynamic process to be obtained. The analysis of the experimental results requires that a particular dynamic model be assumed. Information on the dynamics is obtained from studies of the dependence of emission intensity on two parameters the frequency (or the wavelength) of emission and on time. The function 7(vem, t) may be investigated by two types of potentially equivalent experiments ... [Pg.96]

Study the AG° dependence at different temperatures. This was done by Dutton and co-workers for the electron transfers from Bph to and Qa to (Bchl)2 in Rhodobacter sphaeroides photosynthetic reaction centers [139,140], which take place over about 13 A and 25 A, respectively [18], The rates were measured between 10 K and 300 K in series in which quinone substitutions provide AG° ranges of 0.5 eV and 0.8 eV for the two reactions respectively. The following conclusions were deduced from a thorough analysis of the experimental results ... [Pg.31]

Now the type of batch-solids flowing-fluid reactor that we find convenient to use depends on whether the deactivation expression d2ildt is concentration independent or not. When it is concentration independent, any type of batch-solids system may be used and can be analyzed simply, but when it is concentration dependent, then unless one particular type of reactor is used (that in which is forced to stay unchanged with time) the analysis of the experimental results becomes horrendously awkward and difficult. [Pg.478]

However, this is not the only factor influencing the emission intensities. In fact, already PUO2 shows a smaller 5 f emission intensity than Np02 (Fig. 26). This can only be explained by different final state multiplet intensity distributions for Np02 and PUO2. This kind of considerations makes a more quantitative analysis of the experimental results difficult. [Pg.247]

Interactions between adsorbates, so-called lateral interactions, on transition metal surfaces have at least been known for as long as diffraction techniques have revealed that adlayers can form very well-defined structures at low temperatures. The importance of these interactions for kinetics at higher temperatures has only more recently been acknowledged. There may be various reasons for that, both experimental and theoretical. To show the importance of the lateral interactions in a kinetic experiment it is necessary that a system is well-defined, so that other possible causes for the experimental results can be excluded. For the same reason a system should be simple, which also helps in the analysis of the experimental results, because the relation between lateral interactions and their effects is generally complex. Only in recent years all these conditions have been met. ... [Pg.119]

The analysis of the experimental results is further facilitated by major advances in computational power and with the rapid development of theoretical methodology1,2. This had allowed more accurate results than before, and thus the theoretical investigation of ET has been significantly pushed ahead, Quantum-chemical calculations of spin densities in radical ions have proved to be important for interpretation of experiment results related to the hyperfine structure of the ESR spectra of the radical ions. [Pg.82]

A careful analysis of the experimental results of Brauer in terms of Benjamin s theory (Section III, C) indicated (F7) the interesting fact that, for all the pure liquids (i.e., liquids not containing surface-active materials in solution), the rate of increase of the Benjamin amplification factor with the Reynolds number, dCL/d Nnr), was the same at the point of onset of rippling. [Pg.189]

The appropriate analysis of the experimental results will depend on the experimental objectives, the design used, and the characteristics of the data collected during the experiment. In many cases, a simple examination of a tabular or... [Pg.66]

For nano HAP product, its size and distribution and appearance of the particles are the major quantity indexes. In addition, chemically the mole ratio of Ca/P essentially characterizes the purity of the product. All these are taken as the criteria for comparison and analysis of the experimental results. [Pg.320]

It should be noted that melting takes place along most of the extruder. Indeed, the production capacity of plasticating extruders is frequently determined by their plasticating capacity. Further visual analysis of the experimental results reveals a tendency of the melt pool to penetrate under the solid bed and, occasionally, to completely surround it the continuity of the solid bed is frequently broken and a melt filled gap appears (e.g., turn 15.5, Fig. 9.23). This tendency for solid bed breakup seems to originate in the tapered sections of the extruder, and it appears to be a source of surging (i.e., fluctuation in time of temperature, pressure, and flow rate) of the extmdate at the die, as well as a source of entrapping some air bubbles into the melt stream. [Pg.476]

In the present paper we extend our analysis of the experimental results obtained from this small deformation regime and we show that the result found by Reissner for the deformation of shallow spherical caps represents an excellent analytical approximation for the interpretation of the measurements. This result is varified by finite element modelling (FEM) and by experimental variation of the force probe geometry and radius as well as wall thickness of the studied capsules. This result is also applicable for other capsule deformation measurements, since it is independent of the specific Young s modulus. Furthermore, we report on speed dependent measurements that indicate the glassy nature of PAH/PSS multilayers. [Pg.118]

Here we show how the modified Kubo formula (187) for p(co) leads to a relation between the (Laplace transformed) mean-square displacement and the z-dependent mobility (z denotes the Laplace variable). This out-of-equilibrium generalized Stokes-Einstein relation makes explicit use of the function (go) involved in the modified Kubo formula (187), a quantity which is not identical to the effective temperature 7,eff(co) however re T (co) can be deduced from this using the identity (189). Interestingly, this way of obtaining the effective temperature is completely general (i.e., it is not restricted to large times and small frequencies). It is therefore well adapted to the analysis of the experimental results [12]. [Pg.315]

To improve the analysis of the experimental results, it appears adequate to plot log(xi/xi>0) vs. log(x2/x2,o)y as indicated in Figure 1, and to calculate the slope—i.e., kreh by a least-squares method. [Pg.38]

Phase diagrams of DMPC foam bilayers. The analysis of the experimental results for the foam bilayer thickness and the critical concentration for formation of the foam bilayer... [Pg.271]

All the experimental studies described below have, at least in the initial analysis of the experimental results, related the macroscopic measured quantity to a molecular quantity defined by the formula referred to as the X convention in Table 1. The molecular quantity so extracted will then be in the X convention, provided the macroscopic quantity is defined by the first of the equalities in eqn (7.26) if the macroscopic quantity is defined by the second equality, then the molecular quantity will be in the B convention. [Pg.265]

The analysis of the experimental results by the theory of Kimura et al. give interesting clues for understanding the polypeptide liquid crystal. In Fig. 22 the parameters fi, which are related to the attractive dispersion force proposed by Maier and Saupe and can be obtained from the slopes in the 1/S vs. 1/T plots or the values of Tj, are plotted against the dielectric constants of solvents. B is... [Pg.65]

Therefore, the approach followed in this chapter considers pseudo-binary diagrams, i.e., equilibria involving the third component are, however, neglected, but modifications due to the presence of the solute are considered on the binary system. We will observe in the analysis of the experimental results that this approach can provide interesting information regarding the evolution of the SAS process, and the morphology and dimension of the precipitated particles. A rationalization of the experimental results is also proposed. [Pg.135]

The construction of a kinetic model for an animal cell culture involves several steps a kinetic analysis of the experimental results with the formulation of hypotheses on the nature of the rate-limiting steps the choice of rate expressions describing the influence of these phenomena on the cellular processes evaluation of parameter values and validation of the model with different experimental results. In this section a general methodology is described for the modelling of cell cultures, and the procedure is illustrated on the kinetics of a hybridoma cell. (For a summary of terms used, see Table 4.3.3.)... [Pg.160]

Although the JT effect has been discovered in 1937 as a very general phenomenon, it had to wait until 1952 for its first evidence by EPR (electron-paramagnetic resonance) [10]. In the first period, soon after this experiment, the phenomenon was detected in only a very limited class of systems and the main effort in this field has been theoretical. This has led to mainly mathematical developments and sophistications rather than to the analysis of the experimental results. In last 40 years the situation has been completely changed and the JT effect is being investigated both experimentally and theoretically [11]. [Pg.348]

Brish et al. [134] considered possible mechanisms of laser initiation, including shock caused by the light, pressure, electrical breakdown, and photochemical ion and thermal processes. An analysis of the experimental results for lead azide and PETN indicated that only the thermal theory of initiation could explain the data. The light energy is converted into Shockwave energy which initiates the explosives. [Pg.241]


See other pages where ANALYSIS OF THE EXPERIMENTAL RESULTS is mentioned: [Pg.522]    [Pg.311]    [Pg.88]    [Pg.127]    [Pg.340]    [Pg.165]    [Pg.385]    [Pg.41]    [Pg.46]    [Pg.65]    [Pg.91]    [Pg.139]    [Pg.780]    [Pg.92]    [Pg.76]    [Pg.151]    [Pg.170]    [Pg.239]    [Pg.558]    [Pg.362]    [Pg.244]    [Pg.372]    [Pg.240]    [Pg.163]    [Pg.450]    [Pg.500]   


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Analysis of experimental results

Analysis of results

Experimental analysis

Results analysis

The Experimental Results

The experimental analysis

The results

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