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Determination classical analysis

The term design-analysis is used to emphasize the essential, but not dominant, role of analysis in the overall structural design process. Analysis plays no role whatsoever in dress design (with the possible exception of the now-classical analysis of a strapless evening gown). However, engineering design of a structure must involve analysis in the form of mechanistic relationships. Those mechanistic relationships must be used to quantitatively determine how to create the structural capabilities and then to match them to the structural requirements. The dis-... [Pg.386]

Early in the 20th century chemists began to research and exploit physical properties of the analyte properties, such as conductivity, electrode potential, light absorption or emission, mass-to-charge ratio and fluorescence for solving analytical problems. Classical principles remain useful in modem analytical instruments and methods. In comparison to classical methods the output of instrumental methods is a signal from which the result of the analyses is calculated. Instrumental analysis is most useful for elemental determinations at minor and trace levels (about 1% all the way down to 1 atom)—in this range classical analysis does not perform well. [Pg.527]

Note that in preliminary calculations the sum of replicated design points-trials is taken as the response, and thus the number of replicated design points n is introduced Eq. (2.70). As there exists replication of trials, it is evident that the error sum of squares is calculated in accord with analysis of variance methodology. To enable comparison of such variance determination with classical analysis of variance, it is necessary to transform Table 2.107 into Table 2.108. [Pg.287]

Thus, we have attempted to give, in the present appendix, an idea of the various methods of determining classical and quantum mechanical polarization moments and some related coefficients. We have considered only those methods which are most frequently used in atomic, molecular and chemical physics. An analysis of a great variety of different approaches creates the impression that sometimes the authors of one or other investigation find it easier to introduce new definitions of their own multipole moments, rather than find a way in the rather muddled system of previously used ones. This situation complicates comparison between the results obtained by various authors considerably. We hope that the material contained in the present appendix might, to some extent, simplify such a comparison. [Pg.265]

The Si/Al ratios of the dealuminated samples were determined by classical analysis. The compositions of the investigated zeolites are summarized in Table 1. [Pg.156]

Classical analysis of the two-state model using parabolic diabatic surfaces produces a Gaussian-shaped IV band having a full-width at half-maximum intensity that is only determined by Umax 14,55... [Pg.196]

The unprecedented spatial resolution of the Atomic Force Microscope makes it possible to examine the plastic deformation of shocked or impacted solids at the atomic or molecular levels. At these levels the molecular and lattice behaviors are determined by quantum mechanics. While the AFM is limited to imaging only the surface of the deformed solid, in many if not most shocked or impacted solids the deformation extends throughout the sample. It is necessary to infer the deformation in the interior of the sample from the surface information. In the case of severe deformation as found in shear bands the assumption has been made that the severely distorted surface features extend throughout the similar severely distorted regions in the interior of the solid. This assumption yields reasonable results not accessible by a classical analysis. [Pg.120]

Vol. 1C, Classical Analysis Gravimetric and Titrimetric Determination of the Elements, New York Elsevier, 1962. [Pg.337]

Solution structure determination essentially relies on NMR data, via either a classical analysis of the number of signals and of their chemical shifts with the help of two-dimensional COSY, NOESY, and NOEDIF measurements, or the more sophisticated investigation of both lanthanide-induced shifts (LIS) and relaxation times (LIR). When the major species in solution is the heterobimetallic helicate, analysis of the... [Pg.495]

Analytical methods to determine carbon in the light alkali metals have to be highly sensitive, as there are only very low concentrations present in the molten metals. Therefore, monitoring of the chemical activities of carbon seems to be more favourable than the classical analysis of combustion and determination of the carbon dioxid evolved. This method is based oh an analytical vacuum distillation of the dissolving alkali metal samples collected in alumina crucibles. The sensitivity of the method is not sufficient to estimate the carbon contents in unsaturated solutions of carbon in lithium or sodium. The hydrolysis and evolution of acetylene has also been applied for the estimation of the lithium acetylide contents. This method may be disturbed by side reactions, which occur in the presence of higher amounts of nitrogen. [Pg.142]

By way of a final comment on this example we noted that the data was collected under pseudo first order conditions i.e. one reagent in excess. This ubiquitous approach was essential to enable the determination of second order rate constants using a first order fit by classical analysis using explicit functions (usually sums of exponentials). In the pseudo first order simplification a 2" order rate constant is calculated from the observed pseudo first order rate constant. [Pg.57]

Not much data is available concerning molecular weight distributions. For water-soluble polymers prepared in bicontinuous or water-in-oil microemulsions, it was precisely because of the high molecular weight values that their distribution could not be determined. Indeed, a classic analysis by Gel Permeation Chromatography (GPC) is not possible owing to exclusion and adsorption phenomena in the column pores. [Pg.202]

Amplitudes of density fluctuations at different wavelengths follow independent Gaussian (also called normal) statistics (see Sect. 9.3.6, Chap. 9, Vol. 1), and their mean spectral power is distributed in an almost scale-invariant manner, described above. The absolute normalization was determined by the COBE satellite to be 1 part in 100,000. Their evolution can be analyzed initially with the help of the linearized gravitational equations. The classical analysis, originally performed by Jeans (1902), leads to the conclusion that fluctuations above the Jeans-scale are unstable and they are at the origin of the formation of the oldest structures (for a modern textbook on the subject, see Peacock 1999). [Pg.628]

The methodology to answering these parameter estimation and set-based questions relies on different mathematical approaches. In principle, the parameter identification of chemical kinetic models can be posed as classical statistical inference [17,19-21] given a mathematical model and a set of experimental observations for the model responses, determine the best-fit parameter values, usually those that produce the smallest deviations of the model predictions from the measurements. The validity of the model and the identification of outliers are then determined using analysis of variance. The general optimizations are computationally intensive even for well-behaved, well-parameterized algebraic functions. Further complications arise from the highly ill-structured character... [Pg.255]

A simple possibility to obtain a detailed information about the stabilizer system in PVC waste can be seen in the classic analysis methods which are common practice in inorganic chemistry of the separation and determination of cations. The only difficulty is to find an easily practical way to get the metallic cations into water phase. For this purpose, the PVC sample is dissolved in cyclohexanone and the received solution used for a liquid/liquid-extraction with nitric acid containing water. After phase separation, the different cations are found in water solution. [Pg.30]

A comprehensive reference work which covers all types of analytical determinations and gives sufficient details of recommended methods for dir t use or at least to provide a starting point for further investigation is Comprehensive Analytical Chemistry by C. L. and D. W. Wilson (Elsevier) which is to be in live volumes, some of them in several parts. Volume 1, Classical Analysis (1959-62), is in three parts. A and B contain the... [Pg.254]

The existence and properties of individual molecules, atoms, and ions in the gaseous state provide a fundamental basis for elemental spectrometric analytical determinations. Classical techniques based on these principles have been utilized for decades for the major, minor, and trace analysis of substances in virtually every field of science. The enhancement of techniques based on these properties has recently resulted in technology that exhibits ultratrace analysis sensitivity (sub-part-per-million detectability) and allows expansion of the scope of analysis to the rarer and more exotic elements. A basic understanding of some of the fundamental atomic properties of the elements that are used for mass spectrometric analysis is required to fully utilize this technology. [Pg.8]

Now a correction for the non-ideal character of the multiphase topology must be performed. In the classical analysis this is a manual evaluation step which results in the subtraction of a slowly varying background [46, 72, 73]. Here the background determination is replaced by the result of a low-pass Alter, applied to the scattering image at the present state of evaluation [74],... [Pg.17]

Wilson, C.L. and Wilson, D.W. (Eds.), Comprehensive Analytical Chemistry, Vol. 1C, Classical Analysis. Gravimetric and Titrimetric Determination of the Elements, Elsevier, Amsterdam, 1962. [Pg.1386]

The Restart check box can be used in ctiii junction with the explicit editing of a IIIX file to assign completely user-specified initial velocities. This may be useful in classical trajectory analysis of chemical reactions where the initial velocities and directions of the reactants are varied to statistically determine the probability of reaction occurring, or n ot, in the process of calculating a rate con -Stan t. [Pg.313]

Analytical Procedures. Standard methods for analysis of food-grade adipic acid are described ia the Food Chemicals Codex (see Refs, ia Table 8). Classical methods are used for assay (titration), trace metals (As, heavy metals as Pb), and total ash. Water is determined by Kad-Fisher titration of a methanol solution of the acid. Determination of color ia methanol solution (APHA, Hazen equivalent, max. 10), as well as iron and other metals, are also described elsewhere (175). Other analyses frequendy are required for resia-grade acid. For example, hydrolyzable nitrogen (NH, amides, nitriles, etc) is determined by distillation of ammonia from an alkaline solution. Reducible nitrogen (nitrates and nitroorganics) may then be determined by adding DeVarda s alloy and continuing the distillation. Hydrocarbon oil contaminants may be determined by ir analysis of halocarbon extracts of alkaline solutions of the acid. [Pg.246]

Nickel also is deterrnined by a volumetric method employing ethylenediaminetetraacetic acid as a titrant. Inductively coupled plasma (ICP) is preferred to determine very low nickel values (see Trace AND RESIDUE ANALYSIS). The classical gravimetric method employing dimethylglyoxime to precipitate nickel as a red complex is used as a precise analytical technique (122). A colorimetric method employing dimethylglyoxime also is available. The classical method of electro deposition is a commonly employed technique to separate nickel in the presence of other metals, notably copper (qv). It is also used to estabhsh caUbration criteria for the spectrophotometric methods. X-ray diffraction often is used to identify nickel in crystalline form. [Pg.13]


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See also in sourсe #XX -- [ Pg.317 ]




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