Averages, determining

These relations are good for single-pass tube side units however, for multipass units, the number of available vapor tubes must be determined at the end of the first and each succeeding pass, as the lower liquid carrying tubes must not be considered as available tubes. Thus, G" should be evaluated for each pass, and the individuals evaluated separately, or an average determined as the average of the pass average values ofh, . 

Values are the averages determined from measuring the diameters of coated particles. 

Xylene is used as a solvent in paint. A certain painting operation evaporates an estimated 3 gal of xylene in an 8-hr shift. The ventilation quality is rated as average. Determine the quantity of dilution ventilation air required to maintain the xylene concentration below 100 ppm, the TLV-TWA. 

We have performed a similar averaging of the crystal data, in which, in addition to the crystallographic structures chosen by Voet and Rich, some more recent crystal structures were taken into consideration.20,22 These new calculated average values of the bond lengths and angles compare quite well with the averages determined by Voet and Rich.7... 

Figures 4 and 5 show plots of the apparent number and weight averages determined by SFFF plotted against the corresponding data from DCP measurements. For perfect agreement, the data would lie along a line with slope of one with an intercept of zero. The deviation of these plots from linearity at larger particle sizes is probably due to a steric effect which occurs in SFFF when the particle diameter becomes a significant fraction of the channel thickness (2). The particle size limit above which the SFFF channel used in this work is expected to exhibit this effect is...

Values are average determinations from three separate purifications. 

We have recently determined the structural parameters and composition of some asphaltene samples obtained from the Synthoil and Exxon Donor Solvent (EDS) liquefaction processes. The particular EDS sample used was sufficiently volatile for analysis by ultrahigh resolution mass spectrometry, so we could obtain very detailed data on its composition in terms of the distribution of individual carbon-number homologs. Information from this approach, integrated with data from NMR, IR, molecular weight determinations, elemental analyses, and separations furnished us with a novel and detailed insight into the nature of these asphaltenes. The excellent agreement observed between composites calculated from the detailed MS data, where available, and the averages determined by NMR, IR, and elemental analyses reinforces the credibility of the approaches used and allows extrapolations to heavier samples that are not amenable to detailed MS characterization. 

Error = 100 x (experimental value - trae value) / (true value) Average % Error = (Z1% Error for 16 amino acidsi) /16 These calculations were repeated substituting the true value with analyzed value . Analyzed values are the overall average determined by all the participants and may represent a more realistic figure than the theoretical values, which were determined by protein or nucleic acid sequencing. These values were used to compare the errors of the pre-hydrolyzed and protein samples. In analyzing data, we excluded sites with errors >3 standard deviations from the mean. 

For example, the chromogenic creatinine method may on average determine creatinine values 15% too high, which then constitutes the mean bias. For individual samples, the particular bias may be slightly higher or lower than 15% depending on the actual chromogenic content. 

Vapor at a saturation pressure pc and superheat temperature T is condensed by a counter water flow in a heat exchanger of area A. The inlet temperature of the water is Twt. The flow rates of the vapor and water are ms and m,. Assume the total heat transfer coefficients to be Uy and U2 for parts 1 and 2 of the exchanger as shown in Fig. 7P-Z Log-mean averages may be replaced by arithmetic averages. Determine the exit temperature of the water and the exit quality of the vapor. 

The domain of an atmospheric model—that is, the area that is simulated—varies from a few hundred meters to thousands of kilometers (Table 25.1). The computational domain usually consists of an array of computational cells, each having a uniform chemical composition. The size of these cells, that is, the volume over which the predicted concentrations are averaged, determines the spatial resolution of the model. Variation of concentrations at scales smaller than the model resolution cannot easily be resolved. For example, concentration variations over the Los Angeles basin cannot be described by a synoptic scale model that treats the entire area as one computational cell of uniform chemical composition. 

What equation describes the intensity decay for a distance distribution Unfortunately, the donor decay can only be described by an integral equation. The intensity decay for those D-A pairs at a (fistance ris g ven by Eq. [14.1]. However, these D-A pairs with a uiuque distance rcaimot be individually obsoved. Rather, one observes a weighted average determined by P(r)L The donor intensity decay is a smtunatioo of the intenrity decays for all acces-able distances and is usually written as... 

In other words, a velocity can be defined only with respect to a given point in space-time and relative to a particular observer. Since one cannot measure velocity at an infinitesimal point in time or space, any measurement of a rate or a velocity requires averaging the change in the quantity of interest at some point in space over a period of time as well as averaging it over a volume at some point in time. The period of time over which the quantity is averaged determines the time scale and the volume determines the space (or distance scales). We note that the measurement precision of the resulting rate or velocity is directly proportional to the time scale and inversely proportional to the distance scales. But since these time and distance scales may be arbitrarily determined (within certain limiting constraints), the observer can influence the measurement precision and thus influence the power required to measure... 

Coll and Gilding [39] reviewed the theoretical justification for comparing M[rj] values for different polymers at the same retention volume, i.e. the universal calibration procedure, in analysing the SEC of i-PP samples in TCB at 135°C. The universal calibration line for polypropylene was derived from polystyrene and linear polyethylene standard materials, and molecular mass averages determined from viscosity measurements in decalin solutions and the... 

One of the commonest solvents is m-cresol. Solutions are prepared by heating at 100°C for about Ih or at room temperature overnight, continuously purging with nitrogen. Prince and Stapelfeldt [53] have described the analysis of nylon-6 by SEC. Since nylon molecular mass standards were not available, calibration was achieved with polystyrene standards and a g-factor of 13.13. The reproducibility of the molecular mass averages determined was, however, only about 10%, and this compared with 6% for polystyrene. This relatively poor reproducibility was attributed to the presence of a high molecular mass tail in the molecular mass distribution of the nylon sample. 

The molar mass average determined with viscosimetric measurements is called... 

The half-height of this peak is higher than the peak at 998cm The transition moment angle of this peak is estimated to be 23° with the chain axis [4]. As shown in Figure 2(c), the Herman s orientation averages determined from this peak is always lower than the peaks at 841 and 981 cm", respectively, and this suggests that this peak is even more sensitive to the disordered material. In order to improve the curve... 

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