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Measurement Standards

Since the net free energy change for the cycle is zero, the difference between the computable free energies for transforming L to if, when bound to protein and when dissolved in water, is equal to the difference between the measurable standard free energies of binding L and if to protein, i.e., the difference in affinity... [Pg.136]

Standards Engineering Standards Engineering Society 6700 Penn Avenue South Minneapolis, Minn. 55423 A bimonthly in which general news and technical articles dealing with all aspects of standards and U.S. and foreign articles on standard materials and caUbration and measurement standards are presented. [Pg.24]

Calibration. Cahbration of lab instmments is important to the accuracy of test results. CaUbration, the use of an accepted standard to adjust an instmment or measurement standard so as to improve the accuracy of the instmment or measurement, is an essential requirement of both the U.S. Food and Dmg Administration (FDA) Good Manufacturing Practice (GMP) (24) and the ISO 9000 standards (25). [Pg.367]

Other New Methods. Because the values obtained are dependent on the conditions of measurement, standard test procedures are under review by ISO for determination of cold-water solubiUty of water-soluble dyes (38) determination of the solubiUty and solution stabiUty of water-soluble dyes (39) and determination of the electrolyte stabiUty of reactive dyes (40). [Pg.377]

AGA. Manual of Petroleum Measurement Standards. Chapter 14—Natural Gas Fluids Measurement, Section 3 Orifice Metering of Natural Gas and Other Related Hydrocarbon Fluids. AGA Report No. 3. (ANSI/API 2530, 1985 and CPA 8185, 1985). American Gas Association, Cleveland, Ohio. [Pg.143]

The accuracy in RBS results is -3% for areal densities and better than 1% for stoichiometric ratios. This high accuracy is obtained only when all relevant quantities are measured or evaluated carefully. Pitfalls which often prevent RBS from achieving its full accuracy are described elsewhere [3.129]. Calibration can be achieved by measuring standards obtained by either implanting into or depositing on a light element (silicon) a known amount of a much heavier element (e.g. Ta or Sb). [Pg.147]

Uncertainty on tlie other hand, represents lack of knowledge about factors such as adverse effects or contaminant levels which may be reduced with additional study. Generally, risk assessments carry several categories of uncertainly, and each merits consideration. Measurement micertainty refers to tlie usual eiTor tliat accompanies scientific measurements—standard statistical teclmiques can often be used to express measurement micertainty. A substantial aniomit of uncertainty is often inlierent in enviromiiental sampling, and assessments should address tliese micertainties. There are likewise uncertainties associated with tlie use of scientific models, e.g., dose-response models, and models of environmental fate and transport. Evaluation of model uncertainty would consider tlie scientific basis for the model and available empirical validation. [Pg.406]

Galvanic cell measurements, standard free energy of formation... [Pg.462]

Table 10.5 gives a preliminary comparison of performance of dielectric elastomer with other acmator technologies. The reported values are collected from different sources and are not based on uniform measurement standards. ... [Pg.284]

Over the years, scientists have measured standard enthaipies of formation of many chemicai substances. Reference books such as the CRC Handbook of Chemistry and Physics contain tabies of these vaiues, and Appendix D of this text iists vaiues for many common substances. [Pg.406]

The uncertainties in the measurements (standard deviations) are placed in the diagonal matrix... [Pg.532]

There are two main uses of a RM calibration and method performance checking. ISO Guide 32 (1997) deals with the use of RMs for calibration purposes. RMs used for calibration purposes are usually RMs prepared by synthetic means. Commonly, the property values of these RMs are known from preparation, and verified by some kind of suitable measurement technique. This can be a technique directly providing a value for a property of interest, or a technique that allows the comparison of the new material against older measurement standards. [Pg.9]

ISO Guide 32 provides guidance in two ways. Apart from the guidance on using RMs for calibration purposes, it also provides information on the preparation and use of calibrants in a laboratory, and checking them against other RMs or measurement standards. [Pg.9]

NRCC Institute for National Measurements Standards, National Research... [Pg.258]

API, Metering assemblies, in Manual of Petroleum Measurement Standards, Chap. 6, American Petroleum Institute, 1983. [Pg.755]

If it has not been adequately addressed during method development, study the selectivity by analysing samples ranging from pure measurement standards spiked with potential interferents, to known mixtures that match real-sample compositions. Serious interferences need to be eliminated, but minor effects can be tolerated and included in the estimation of method bias and its associated uncertainty. [Pg.78]

Calibration Operation that establishes the relationship, obtained by reference to one or more measurement standards, between the response of an instrument and the values of the standards. [Pg.277]

It follows that the standard molar entropy of the transition can be derived from the measured standard molar enthalpy of transition through the relationship... [Pg.18]

Weight of unused bed (WUB), 1 653 Weight per epoxide (Wpe), 10 355, 385 Weights and measures standards, 15 768 Weigh vessels loading, 26 256 Weigh vessels... [Pg.1018]

I-3.6.4 A useful reference for electronic hydrogen gas measurements is API Manual of Petroleum Measurement Standards, Chapter 21, Section 1 — Electronic Gas Measurement. [Pg.171]

Briefly explain the differences between calibrating an analytical balance and calibrating a pH meter and what happens if the measured standard does not give the correct result. [Pg.176]

Experimental values of bond dissociation enthalpies are scarce compared with the data available for standard enthalpies of formation. This is not surprising because most chemical reactions that have been studied thermochemically involve the cleavage and the formation of several bonds. The measured standard reaction enthalpies are thus enthalpy balances of various bond dissociation enthalpies, whose individual values are often unknown. Consider, for example, reaction 5.10, where the arene ring in (q6-bcnzene)chromium tricarbonyl is replaced by three carbonyl ligands. The enthalpy of this reaction at 298.15 K,... [Pg.64]

When K is large, once again the response appears as a simple reversible electron transfer, but the measured standard potential, E°, is shifted towards more negative values compared to the standard potential, E01, of the couple Ox/Red by a factor of ... [Pg.70]

Sampling of odourous air for olfactometric measurement Standardization of olfactometric measurements... [Pg.46]

While the volume of concentrate can be determined based on plant capacity and recovery, the evaporation rate at any given site varies with climate. To determine the evaporation rate of fresh water at certain locations, a standard pan evaporation measurement is taken. Evaporation pans are small, open air pans filled with water from which losses in water due to evaporation are measured. Standard size Class A evaporation pans are most commonly used, which are 1.207 m in diameter and 0.25 m in depth. The daily change in depth, minus any rainfall, is used to determine the evaporation rate in mm/day. This rate takes into account the effects of climate on evaporation rate, but corrections for pond area and salinity must be made when determining the evaporation rate of a specific evaporation pond. [Pg.60]

Model performance is now receiving critical attention because of the need for cost-effective control measures. Standard statistical performance descriptors can sometimes mislead a prospective user therefore, more specialized tests are being devised. Various model types are being compared for a specified set of initial and boundary conditions. It is apparent from these studies that added fidelity is purchased at the expense of added complexity of a logical structure that must represent the controlling phenomenology. [Pg.679]

Optical and FTIR instrumentation. Absorption spectra were taken on three instruments. A Hewlett Packard 8450 UV/Vis Spectrophometer was used for the visible region of the spectrum. This instrument was computer control led and used to measure standard absorption spectra as well as absorption difference spectra. A Cary 14 Spectrophotometer was used for the near IR region, and an IBM IR/90 Series... [Pg.331]

In this book, standard is used only in the sense of written standard and the term measurement standard or etalon (in French etalon )(see slide 36) is used to describe chemical or physical standards used for calibration purposes such as chemicals of established purity and their corresponding solutions of known concentration, UV filter, weights, etc. They are also called reference materials. [Pg.10]

And also as chemical or physical measurement standard, which is used for calibration purposes... [Pg.10]

Samples, reagents, measurement standards and reference materials must be stored so as to ensure their integrity. [Pg.105]

The usual way to perform calibration is to subject known amounts of the parameter (e.g. using a measurement standard or reference material) to the measurement process and monitor the measurement response... [Pg.184]


See other pages where Measurement Standards is mentioned: [Pg.158]    [Pg.19]    [Pg.480]    [Pg.413]    [Pg.116]    [Pg.548]    [Pg.290]    [Pg.314]    [Pg.855]    [Pg.67]    [Pg.360]    [Pg.422]    [Pg.110]    [Pg.9]    [Pg.136]    [Pg.121]    [Pg.4]    [Pg.14]    [Pg.37]   
See also in sourсe #XX -- [ Pg.14 , Pg.291 ]

See also in sourсe #XX -- [ Pg.53 , Pg.55 ]




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Standard measures

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