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General qualitative analysis

I Gallates and tannates are of rare occurrence in general qualitative analysis. [Pg.393]

For a long time qualitative analysis was mainly carried out with DCP systems, while the sequential or direct reading ICP systems were too time- and sample-consuming for a general survey analysis. With the improved simultaneous observation of multiple emission Unes via echeUe spectrometer, a general qualitative analysis of unknown samples becomes easily possible under robust plasma conditions. [Pg.490]

There is little chance of giving a general qualitative analysis of (1.6) except for low-dimensional cases. Limit cycle and chaotic behaviour might occur in certain situations, as has been demonstrated. [Pg.12]

What are the main groups in the general qualitative analysis scheme described in this chapter Describe the steps and reagents necessary to identify each group. [Pg.803]

Qualitative analysis methods should have well-grounded and generally adopted quantitative reliability estimations. At first the problem was formulated by N.P. Komar in 1955. Its actuality increased when test methods and identification software systems (ISS) entered the market. Metrological aspects evolution for qualitative analysis is possible only within the scope of the uncertainty theory. To estimate the result reliability while detecting a substance X it is necessary to calculate both constituents of uncertainty the probability of misidentifications and the probability of unrevealing for an actual X. There are two mutual complementary approaches to evaluate uncertainties in qualitative analysis, just as in quantitative analysis ... [Pg.24]

Qualitative results of checklist analyses vary, but generally the analysis produces the answers yes, no, not applicable, or needs more information. The checklist is included in the PrHA report to summarize the noted deficiencies. Understanding these deficiencies leads to sa fety improvement alternatives for consideration, and to identified hazards with suggested actions. I igtires 3.3,1-4 and 3.3.1-5 present checklist analyses of the Dock 8 HF Supply and the Cooling tower chlorination respectively. [Pg.78]

Because most research effort in the human reliability domain has focused on the quantification of error probabilities, a large number of techniques exist. However, a relatively small number of these techniques have actually been applied in practical risk assessments, and even fewer have been used in the CPI. For this reason, in this section only three techniques will be described in detail. More extensive reviews are available from other sources (e.g., Kirwan et al., 1988 Kirwan, 1990 Meister, 1984). Following a brief description of each technique, a case study will be provided to illustrate the application of the technique in practice. As emphasized in the early part of this chapter, quantification has to be preceded by a rigorous qualitative analysis in order to ensure that all errors with significant consequences are identified. If the qualitative analysis is incomplete, then quanhfication will be inaccurate. It is also important to be aware of the limitations of the accuracy of the data generally available... [Pg.222]

Many of the most important naturally occurring minerals and ores of the metallic elements are sulfides (p. 648), and the recovery of metals from these ores is of major importance. Other metal sulfides, though they do not occur in nature, can be synthesized by a variety of preparative methods, and many have important physical or chemical properties which have led to their industrial production. Again, the solubility relations of metal sulfides in aqueous solution form the basis of the most widely used scheme of elementary qualitative analysis. These various more general considerations will be briefly discussed before the systematic structural chemistry of metal sulfides is summarized. [Pg.676]

Complex formation, selective precipitation, and control of the pH of a solution all play important roles in the qualitative analysis of the ions present in aqueous solutions. There are many different schemes of analysis, but they follow the same general principles. Let s think through a simple procedure for the identification of five cations by following the steps that might be used in the laboratory. We shall see how each step makes use of solubility equilibria. [Pg.595]

Table 10.32 is a shortlist of the characteristics of the ideal polymer/additive analysis technique. It is hoped that the ideal method of the future will be a reliable, cost-effective, qualitative and quantitative, in-polymer additive analysis technique. It may be useful to briefly compare the two general approaches to additive analysis, namely conventional and in-polymer methods. The classical methods range from inexpensive to expensive in terms of equipment they are well established and subject to continuous evolution and their strengths and deficiencies are well documented. We stressed the hyphenated methods for qualitative analysis and the dissolution methods for quantitative analysis. Lattimer and Harris [130] concluded in 1989 that there was no clear advantage for direct analysis (of rubbers) over extract analysis. Despite many instrumental advances in the last decade, this conclusion still largely holds true today. Direct analysis is experimentally somewhat faster and easier, but tends to require greater interpretative difficulties. Direct analysis avoids such common extraction difficulties as ... [Pg.743]

These techniques are generally able to provide quantitative as well as qualitative analysis of the specimen surface, and a number of them may be used in combination to maximize the amount of information obtained. [Pg.204]

Today an increasing importance of qualitative analysis can be stated in certain fields. This is due to an increasing number of materials under study, especially active agents of interest on the one hand, and the many and diverse ways of synthesis (e.g., by combinatorial chemistry) on the other hand as well as the increasing demands on quality. Because analytical laboratories in research and routine control would be overtaxed in their capacity if full quantitative analyses were done generally, screening methods become more and more significant. [Pg.111]

The ASTM (American Society for Testing and Materials) has published a Standard Practice for General Techniques for Qualitative Analysis (Method E 1252-88). The method describes techniques useful for qualitative evaluation of liquids, solids, and gases using the spectral measurement region of 4000 to 50 cm 1 (above 2500 nm) [1, 2],... [Pg.497]

For a qualitative analysis it is sufficient to be able to apply a test which has a known sensitivity limit so that negative and positive results may be seen in the right perspective. Where a quantitative analysis is made, however, the relation between measurement and analyte must obey a strict and measurable proportionality only then can the amount of analyte in the sample be derived from the measurement. To maintain this proportionality it is generally essential that all reactions used in the preparation of a sample for measurement are controlled and reproducible and that the conditions of measurement remain constant for all similar measurements. A premium is also placed upon careful calibration of the methods used in a quantitative analysis. These aspects of chemical analysis are a major pre-occupation of the analyst. [Pg.612]

In examining numerical approximations it is as well to bear in mind the general qualitative conclusion of our brief examination of symmetry constraints. In broad terms the result was the simpler the model the more severe the effect of any constraint on the variation principle. This result cannot be carried over directly and used in numerical work since numerical approximation schemes can rarely be brought into a sufficiently coherent logical and mathematical form for analysis. Nevertheless it seems likely that this result can be used as a guideline — a rule of thumb . We therefore expect that the imposition of formal constraints and consistency requirements (derived from a higher level of approximation or the exact solution) on numerical approximation schemes is likely to have far-reaching consequences — particularly on the... [Pg.55]

While the theoretician might be interested in the subtle features of a problem which can only be revealed by explicit computation, the organic chemist is more interested in a general qualitative theory which can be directly applicable to problems of interest without the need of computer assistance. Hence, we should reduce the quantitative scheme to a qualitative scheme which can still retain the important features of the theory. The various steps which one has to follow in attempting a qualitative configuration interaction analysis are given below ... [Pg.200]

With this technique, under an especially equipped electron microscope, high-energy electrons are focused on a fine probe and directed at the point of interest in the specimen. The electrons interacting with the sample atoms cause the emission of the characteristic X-rays, which are detected and identified for qualitative analysis and used, generally through suitable standardization, to perform also a quantitative analysis. [Pg.66]


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Qualitative analysis

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