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Critical application value

However, too low a wet pickup can be eqnally problematic and also lead to uneven finish distribution if the liquid phase is discontinuous. The concept of a critical application value (CAV) is useful when discnssing optimal wet pickups. The CAV is defined as the minimum amonnt of dnrable press finish liquid that can be applied to a given cotton fabric withont prodncing a non-uniform distribution of crosslinks after drying and curing. Dye staining tests can be used to determine these distributions. For non-cellulosic fibres, other methods of finish distribution analysis can be used. [Pg.12]

Produced in this way, these materials can be less reliable, with the introduction of unwanted tramp elements. Where proving tests have indicated the suitability of a proprietary alloy for specific application, the same source of material should be used for construction. Published compositional data are typical values cast analyses should be requested for critical applications. [Pg.908]

In addition to the properties noted above, the formulation parameter in iPP-E-plastomer blends have a profound influence on the dynamic loading (e.g., vibration) performance. The load limits of the blend for applications in which dynamic stresses are predominant were studied by using the hysteresis measurement method. However, their technical application requires knowledge of critical load values. [Pg.175]

Because of the convenient mathematical characteristics of the x -value (it is additive), it is also used to monitor the fit of a model to experimental data in this application the fitted model Y - ABS(/(x,. ..)) replaces the expected probability increment ACP (see Eq. 1.7) and the measured value y, replaces the observed frequency. Comparisons are only carried out between successive iterations of the optimization routine (e.g. a simplex-program), so that critical X -values need not be used. For example, a mixed logarithmic/exponential function Y=Al LOG(A2 + EXP(X - A3)) is to be fitted to the data tabulated below do the proposed sets of coefficients improve the fit The conclusion is that the new coefficients are indeed better. The y-column shows the values actually measured, while the T-columns give the model estimates for the coefficients A1,A2, and A3. The x -columns are calculated as (y- Y) h- Y. The fact that the sums over these terms, 4.783,2.616, and 0.307 decrease for successive approximations means that the coefficient set 6.499... yields a better approximation than either the initial or the first proposed set. If the x sum, e.g., 0.307,... [Pg.79]

Two sensibly priced commercial databases for solubility exist [366,507], An article in the journal Analytical Profiles of Drug Substances carries solubility data [496]. Abraham and Le [508] published a list of intrinsic aqueous solubilities of 665 compounds, with many ionizable molecules. It is difficult to tell from published lists what the quality of the data for ionizable molecules is. Sometimes, it is not clear what the listed number stands for. For example, Sw, water solubility, can mean several different things either intrinsic value, or value determined at a particular pH (using buffers), or value measured by saturating distilled water with excess compound. In the most critical applications using ionizable molecules, it may be necessary to scour the original publications in order to be confident of the quality of reported values. [Pg.100]

The first step in the application of the concept was to determine the critical load values for the different regions of eastern Canada. This was done using historical measurements of lake acidity in concert with the Integrated Assessment Model (IAM) which links atmospheric transport and deposition models with water chemistry and empirical biological response models. Details of the method are given in Jeffries and Lam (1993). [Pg.340]

In agricultural applications, the most commonly analyzed constituents are water, protein, starch, sugars, and fiber [16-20]. Such physical or chemical functions such as hardness of wheat, minerals, and food values have no actual relation to chemicals seen in the NIR. These are usually done by inferential spectroscopy. That is, the effect of minerals or the relationship of the spectra to in vitro reactions is used in lieu of chemical analyses to NIR active constituents. Considering that all shipments of grain from the US since the 1980s have been cleared by NIR, it can be argued that this is a critical application of the technique. [Pg.178]

Copper and gold bronze pigments are not as colorfast as aluminum pigments because they decompose to produce colored oxides and corrosion products. However, stabilized pigments (e.g., with a silica coating) are also available for critical applications in binders with high acid values or that react with copper or zinc. [Pg.230]

A fundamental objective of a computer system applied to automate a pharmaceutical GMP operation is to ensure the quality attributes of the drug product are upheld throughout the manufacturing process. It is therefore important that quality-critical parameters are determined and approved early in the validation life cycle. The exercise should be undertaken to a written procedure with base information from the master product/production record file examined and quality-critical parameter values and limits documented and approved for the process and its operation. In addition, the process and instrument diagrams (P IDs) should be reviewed to confirm the measurement and control components that have a direct impact on the quality-critical parameters and data. This exercise should be carried out by an assessment team made up of user representatives with detailed knowledge of both the computer system application and process, and with responsibility for product quality, system operational use, maintenance, and project implementation. This exercise may be conducted as part of an initial hazard and operability study (HAZOP) and needs to confirm the quality-related critical parameters for use in (or referenced by) the computer control system URS. [Pg.578]

It should be noted at this point that there is a consistency in the pKa values measured in pure DMSO by the various techniques. However, there is some uncertainty at present relating to pKa values obtained by acidity function procedures in alcoholic and aqueous DMSO media. Thus one has the unexpected situation that theoretical analysis of the medium effect on p/ a is hampered because the values for a number of weak acids referring to the standard state in water are in doubt. Under these circumstances less than critical application of (6) to many weak acids, including some carboxylic acids, phenols as well as carbon acids, is inadvisable. Of course, (6) is strictly applicable to those cases in which the p/sfa values can be measured in the pure hydroxylic solvents and also for those weak acids which obey the criteria outlined by Cox and Stewart (1976). Despite this difficulty there is now a large body of reliable pKa data in both DMSO and water. Thus in principle it should be possible to account for variations, or reversals, in acidity order in terms of the thermodynamic transfer functions in (6). [Pg.149]

Precision wire-wound resistors are used for critical applications in which low noise and resistance stability are important, but since they are coils, they have an inductive reactance that must be taken into account for ac circuits. By folding the insulated wire in the middle and carefully forming parallel windings, the inductive component can be reduced by about a factor of 100. Precision standard resistors with an accuracy of about 50 ppm in the range of 1 fl to 10 Mfl are available from Electro Science Industries and other companies. These are often combined in the form of decade resistance boxes to provide a wide range of fixed values. [Pg.539]

Using the previous equations, we find that the number of degrees of fieedom is 8 and the t value is 0.49. Using the standard t-test, a P value of 64% is obtained. This means that the probability that the two populations are the same is 64%. Because the P value is greater than 5%, we can say that these two powders are essentially the same. For most applications, powder 1 may be substituted for powder 2. For more exacting applications, a higher P value may be necessary for successfiil powder substitution. As a result, for each ceramic powder application a critical P value for powder substitution should be determined. [Pg.74]

One other area in which the use of molybdenum disulphide may be undesirable for pre-assembly or anti-seize use is when nickel alloys are used in critical applications, especially at high temperatures. Such alloys are extensively used in aviation gas turbine engines, and there have been cases in which serious failures of gas turbines have been attributed to the effect of molybdenum disulphide-based lubricants on high-temperature components Provided these two hazards are kept in mind, molybdenum disulphide dispersions and pastes are of great value as antiseize compounds and as assembly aids. [Pg.279]

The f -value of a structure determined by analysis assumes that the materials used and the quality of workinansliip meet the standards. Poor workmanship and substandard materials used during construction may result in / -values that deviate from predicted values. Therefore, some engineers use a safety factor in their designs based on experience in critical applications. [Pg.204]

Critical load values of acid forming compounds on ecosystems of Asia The experimental data obtained in various countries of East Asia allow us to consider the applicability of methodology of critical loads related to an assessment of... [Pg.492]

An isochoric equation of state, applicable to pure components, is proposed based upon values of pressure and temperature taken at the vapor-liquid coexistence curve. Its validity, especially in the critical region, depends upon correlation of the two leading terms the isochoric slope and the isochoric curvature. The proposed equation of state utilizes power law behavior for the difference between vapor and liquid isochoric slopes issuing from the same point on the coexistence cruve, and rectilinear behavior for the mean values. The curvature is a skewed sinusoidal curve as a function of density which approaches zero at zero density and twice the critical density and becomes zero slightly below the critical density. Values of properties for ethylene and water calculated from this equation of state compare favorably with data. [Pg.116]

Fields of applicability. Figure 15.3 depicts the fields of applicability of pickled stainless steels in chloride-contaminated concrete exposed to temperatures of 20 °C or 40 °C. Fields have been plotted by analysing the critical chloride values obtained by different authors from exposure tests in concrete or from electrochemical tests in solution and mortar and taking into consideration the worst conditions [11-28]. Nevertheless, it should be pointed out that values are indicative only, since the critical chloride content depends on the potential of the steel, and thus it can vary when oxygen access to the reinforcement is restricted as well as when stray current or macrocells are present. For instance, the domains of applicability are enlarged when the free corrosion potential is reduced, such as in saturated concrete. Furthermore, the values of the critical chloride Hmit for stainless steel with surface finishing other than that obtained by pickling can be lower. [Pg.256]

However, small scale users of solvents do not have the benefits of large volumes and the cost of operation of an on site recovery system is unjustified. Nevertheless, the solvent remains recoverable and hence retains a value. Under these circumstances, provided the economics are viable, conglomeration of a solvent obtained from a number of small users is required. This role of collection and subsequent bulk recovery is performed by solvent recovery agents . The reclaimed solvent obtained from such agents is generally of good quality and purity and can often be reused for less critical applications than those serviced by the virgin solvent. [Pg.140]

III. 13. The reference dose rate (RDR) is determined from Eqs (III.l) and (III.2). It is assumed that RTF is 1 in 10 [in.4]. Data need to be developed to establish an internationally applicable value of RTF for the development of sound segregation tables. It is estimated that regular commuters such as sales persons may fly 500 hours each year, hence the MATP for the critical group is assumed to equal 500 h/a Thus, from Eq. (III.l) we obtain ... [Pg.291]


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See also in sourсe #XX -- [ Pg.12 ]

See also in sourсe #XX -- [ Pg.545 ]




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