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Verification direct

The physical content of Eq. (2.2), that the number of uncollided neutrons falls off exponentially with distance, may be subjected to experimental verification directly, and the fact that the form of (2.2) is found to fit the data very well is evidence for the validity of the assumption expressed by Eq. (2.1). [Pg.33]

In these situations, upstream controls with analytical verification directly after the point of introduction should be considered versus API specification testing. For upstream controls which reduce the GTI level to below the API TTC limit, no further evaluation or testing should be required. Knowledge of the GTI chemical reactivity in the subsequent steps with supportive fate and tolerance data may be required to justify the upstream control arguments when the GTI is not reduced to below TTC limits. The analytical approach used in these situations could be a combination of ppm limit tests and fate and tolerance studies using analytical methods based on standard ICH detection limits. [Pg.178]

Where conformity assessment involves intervention of third party, that task is normally carried out by the notified body. The pressure equipment directive enables in addition the national authorities to authorise in their territory user inspectorates for the carrying out of conformity assessment procedures which relate to product verification. These inspectorates shall act exclusively on behalf of the group of which they are part. The placing on the market and putting into service of equipment which has undergone such assessment is however limited to the territory of the authorising Member State and to those Member States which have also proceeded to such authorisation. The equipment concerned shall therefore not bear the CE-marking. [Pg.943]

Membrane Cliaraeterization MF membranes are rated bvtliix and pore size. Microfiltration membranes are imiqiielv testable bv direct examination, but since the number of pores that rnav be obsen ed directlv bv microscope is so small, microscopic pore size determination is rnainlv useful for membrane research and verification of other pore-size-determining methods. Furthermore, the most critical dimension rnav not be obseiA able from the surface. Few MF membranes have neat, cvlindrical pores. Indirect means of measurement are generallv superior. Accurate characterization of MF membranes is a continuing research topic for which interested parties should consult the current literature. [Pg.2045]

Despite these limitations, mobile monitoring systems have been used to obtain useful information, such as the verification and tracking of the St. Louis, Missouri, urban plume. The measurement of a well-defined urban plume spreading northeastward from St. Louis is shown in Fig. 15-2 (7). These data were collected by a combination of instrumented aircraft and mobile vans. Cross-sectional paths were flown by the aircraft at increasing distances downwind. Meteorological conditions of low wind speed in the same direction helped to maintain this urban plume in a well-defined... [Pg.220]

The work of adhesion was determined from the a versus P measurements (see Eq. 11). The work of adhesion between two rubber spheres was found to be 71 4 mJ/m. The work of adhesion reduced to 6.8 0.4 mJ/m in the presence of 0.01 M solution of dodecyl sulfate. Using these measurements of adhesion between rubber in air and a surfactant solution, Johnson et al. [6] provided the first direct experimental verification of the Young s equation (Eq. 40). They also measured... [Pg.100]

Most of the synthetic work directed toward the higher annulenes was caiiied out by Franz Sondheimer and his students, first at Israel s Weizmann Institute and later at the University of London. Sondheimer s research systematically explored the chemistry of these hydrocarbons and provided experimental verification of Hiickel s rule. [Pg.456]

The successful clinical use of titanium and cobalt-chromium alloy combinations has been reported Lucas etal. also investigated this combination using electrochemical studies based on mixed potential and protection potential theories. Verification of these studies was made by direct coupling experiments. The electrochemical studies predicted coupled corrosion potentials of -0.22 V and low coupled corrosion rates of 0.02 ft A/cm. Direct coupling experiments verified these results. The cobalt-titanium interfaces on the implants were macroscopically examined and no instances of extensive corrosion were found. Overall, the in-vitro corrosion studies and the examination of retrieved prostheses predicted no exaggerated in-vivo corrosion due to the coupling of these cobalt and titanium alloys. [Pg.479]

The entropic hypothesis seems at first sight to gain strong support from experiments with model compounds of the type listed in Table 9.1. These compounds show a huge rate acceleration when the number of degrees of freedom (i.e., rotation around different bonds) is restricted. Such model compounds have been used repeatedly in attempts to estimate entropic effects in enzyme catalysis. Unfortunately, the information from the available model compounds is not directly transferable to the relevant enzymatic reaction since the observed changes in rate constant reflect interrelated factors (e.g., strain and entropy), which cannot be separated in a unique way by simple experiments. Apparently, model compounds do provide very useful means for verification and calibration of reaction-potential surfaces... [Pg.221]

Directive 2004/10/EC of the European Parliament and of the Council of 11 February 2004 on the harmonisation of laws, regulations and administrative provisions relating to the application of the principles of good laboratory practice and the verification of their applications for tests on chemical substances... [Pg.12]

Verification means confirmation by examination or direct measurement that specified requirements are met. [Pg.26]

So while the equilibrium approach is attractive and certainly tells us the directions reactions tend to go, the experimental and empirical verification is lacking. [Pg.268]

Although the present results are only theoretical and not yet verified by experiments, it is felt that this approach, although very much simplified with respect to practice, can be used at least as a qualitative guideline in choosing new experiments for product development. These results are therefore useful in a qualitative sense to show sensitivites, trends and directions. Experimental verification may improve the applicability to (semi-)quantitative predictions, or indicate shortcomings in the present approach, which may be accordingly adjusted. [Pg.225]

Laboratory experiments using natural consortia under defined conditions have particular value from several points of view. They are of direct environmental relevance, and their use minimizes the ambiguities in extrapolation from the results of studies with pure cultures. They provide valuable verification of the results of studies with pure cultures and make it possible to evaluate the extent to which the results of such studies may justifiably be extended to the natural environment. It should be appreciated, however, that in some cases the habitats from which the inoculum was taken might already have been exposed to xenobiotics so that natural enrichment (preexposure) could already have taken place. This has been discussed in Chapter 4. [Pg.264]

Ward JAM, JME Ahad, G Lacrampe-Couloume, GF Slater, EA Edwards, BS Lollar (2000) Hydrogen isotope fractionation of toluene potential for direct verification of bioremediation. Environ Sci Technol 34 4577-4581. [Pg.637]

It is important to realize that though the formulas for RME explicitly do not depend on reaction scale, x, since this variable cancels out in the computation, RME does in fact implicitly depend on reaction scale because reaction yields are scale dependent and RME in turn depends on reaction yield. Reaction yields are parameters whose magnitude cannot be predicted theoretically but must be verified experimentally. It does not always follow that a reported yield for a given reaction at a given scale will be the same at another scale. This requires experimental verification. Moreover, the direction of change as the scale is changed is also not predictable. AH of this means that when the same synthesis plan is run at a different scale, different reaction yields will be determined and hence different material efficiency performance values of RME, Em and mass of waste will be obtained. However, the... [Pg.109]

In their broadest application, CRMs are used as controls to verify in a direct comparison the accuracy of the results of a particular measurement parallel with this verification, traceability may be demonstrated. Under conditions demonstrated to be equal for sample and CRM, agreement of results, e.g. as defined above, is proof. Since such possibilities for a direct comparison between samples and a CRM are rare, the user s claims for accuracy and traceability have to be made by inference. Naturally, the use of several CRMs of similar matrix but different analyte content will strengthen the user s inference. Even so, the user stiU has to assess and account for all uncertainties in this comparison of results. These imcertainty calculations must include beyond the common analytical uncertainty budget (i) a component that reflects material matrix effects, (2) a component that reflects differences in the amount of substance determined, (3) the uncertainty of the certified or reference value(s) used, and 4) the uncertainty of the comparison itself AU this information certainly supports the assertion of accuracy in relation to the CRM. However, the requirement of the imbroken chain of comparisons wiU not be formally fulfilled. [Pg.252]

Composition and structure of newly developed additives are commonly examined by IR, NMR, MS and elemental analysis, e.g. recently developed higher MW antioxidants [115]. Infrared spectroscopy is also well suited to the direct verification of compound composition and quantitative determination of additives in polymers. Gray and Neri [116] have used Soxhlet... [Pg.316]

A new experimental method has been introduced to measure the effect of the crystal anapole moment on p decay. The basic hypothesis is very similar to that assumed by Zel dovich. The special idea is to introduce the description of solid-state physics (crystallography) into the process of weak interaction. The p decay rate will be modified due to the presence of crystal anapole moment. If this modification could be detected, the hypothesis for the anapole moment and its coupling to weak interaction will be verified for the first time if this modification could not be detected by this method, an upper limit of up to 1(T6 for the coupling of anapole moment to weak process should be given. This experiment will give direct verification to Zel dovich s assumption. [Pg.313]

Summary of Pollutant Data for the Direct Chill Casting Subcategory Verification Data... [Pg.207]


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See also in sourсe #XX -- [ Pg.124 , Pg.248 ]




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