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Process deviation quantitative

The difference in rates of release of BCNU from wafers produced by the trituration or solution methods is also seen in vivo (11,14), as is shown in Fig. 6. Wafers of PCPP-SA 20 80 were prepared by either the solution or trituration methods, as described above, and were implanted into the brains of rabbits. The animals were sacrificed at various times after implantation and the brains were removed, fixed, and processed for quantitative autoradiography. To quantitate the percentage of the brain exposed to BCNU released from these wafers, the following calculation was performed. The percentage of the brain in which the radioactivity from the tritiated BCNU released from the wafers exceeded the background counts by at least two standard deviation units was plotted as a function of time following implantation in Fig. 6. A control set of rabbits had a solution of BCNU injected directly into the same location in the... [Pg.52]

The curves for these long-term measurements, although they resemble a first-order process, deviate from such kinetics too much to permit derivation of a useful rate parameter for quantitative comparisons. It was found, however, that the initial change of with time of aldehyde treatment was linear within experimental error. For this reason, the experiments described above were repeated, except that tendon samples were removed at very frequent intervals. The results of typical experiments of this type are shown in Fig. 4 for acrolein. Fig. 5 for formaldehyde, and Fig. 6 for acetaldehyde. The total duration of the experiments in this series was 5 min with acrolein, 100 min with formaldehyde, and 30 hr with acetaldehyde. As may be seen, the time course of increase in is linear over these shorter periods. In this way the effects of temperature on the initial increase in T, by aldehyde treatment could be compared quantitatively, even though rate constants for the overall reaction could not be obtained conveniently. [Pg.563]

Both qualitative observations and quantitative measurements cannot be reproduced with absolute reliability. By reason of inevitable deviations, measured results vary within certain intervals and observations, mostly in form of decision tests, may fail. The reliability of analytical tests depends on the sample or the process to be controlled and the amount of the analyte, as well as on the analytical method applied and on the economical expenditure available. [Pg.91]

Pork is the product of a very complex process. All the various characteristics of pork quality cannot be assessed directly in each carcass because these measurements and assessments would be too expensive. Therefore, previous scientific quality assessment of meat is primarily an indirect approach based on a few easily detectable quantitative traits and on the prescription of minimal standards in relation to the product in terms of size or composition and in relation to the production process. The prescriptions and the exclusion criteria vary between countries or between labelling programmes. The most encompassing prescriptions are enshrined in the EC regulation on organic livestock production (EEC No. 2092/91). Owing to this approach, extreme deviations in quality traits and deleterious effects are prevented. However, there is still space left within these framework conditions for huge variability in pork quality. [Pg.145]

As readily observed in most chromatograms, peaks tend to be Gaussian in shape and broaden with time, where W, becomes larger with longer This is caused by band-broadening effects inside the column, and is fundamental to all chromatographic processes.The term, plate number (N), is a quantitative measure of the efficiency of the column, and is related to the ratio of the retention time and the standard deviation of... [Pg.26]

Quantitatively, many observed deviations from simple equilibrium processes can be interpreted as consequences of the various isotopic components having different rates of reaction. Isotope measurements taken during unidirectional chemical reactions always show a preferential emichment of the lighter isotope in the reaction products. The isotope fractionation introduced during the course of an unidirectional reaction may be considered in terms of the ratio of rate constants for the isotopic substances. Thus, for two competing isotopic reactions... [Pg.12]

It is seen that for base-line resolution the peak maxima must be six standard deviations (6a) apart. But for accurate quantitative analysis, employing peak heights measurements, a separation of (4o) is usually quite adequate. Even when peak area measurements are employed, a separation of (4o) will usually provide adequate accuracy, particularly if computer data acquisition and processing is employed with modern software. Therefore, throughout this book, whenever dealing with resolution, or column design, a resolution of (4o) will be assumed. [Pg.60]

A second consideration with logarithmic amplifiers is that because of the complex way in which they operate (3), quantitative data often require reconversion to a linear scale before further calculations can be done. This process requires information about the exact number of channels/decade, and any deviation from true logarithmic behavior (4). Such deviations are sometimes found, particularly in the lowest decade. [Pg.323]

The present sensor could easily discriminate between some kinds of commercial drinks such as coffee, beer and aqueous ionic drinks (Figure 11) [22], Since the standard deviations were 2 mV at maximum in this experimental condition, these three output patterns are definitely different. If the data are accumulated in the computer, any food can be easily discriminated. Furthermore, the taste quality can also be described quantitatively by the method mentioned below. In biological systems, patterns of frequency of nerve excitation may be fed into the brain, and then foods are distinguished and their tastes are recognized [4-8]. Thus, the quality control of foods becomes possible using the taste sensor, which has a mechanism of information processing similar to biological systems. [Pg.390]

The processes may be studied quantitatively by comparing the means and standard deviations of the two populations. The effect of final blend time on lubricant distribution was examined by comparing disintegration time statistics for the grouped data. None was noted. [Pg.83]

The flow modulation technique, in general, appears therefore very well suited for this specific purpose of quantitative diffusivity measurement. However, it also reveals any deviation from a purely diffusion controlled kinetics more clearly than do steady state measurements when, for example, a slow series process is concealed in an apparent diffusion plateau. [Pg.242]


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