Representative method

And here s the two representative methods one would use. Just imagine the carbonyl precursor as a P2P and the amine as methylamine. Visualize.,..man ... 

Representative Method The best way to appreciate the importance of the theoretical and practical details discussed in the previous section is to carefully examine the procedure for a typical precipitation gravimetric method. Although each method has its own unique considerations, the determination of Mg + in water and waste-water by precipitating MgNH4P04 6H2O and isolating Mg2P20y provides an instructive example of a typical procedure. 

Representative Method Although each volatilization gravimetric procedure has its own unique characteristics, the following indirect method for the determination of Si in ores and alloys by formation of volatile SiF4 provides an instructive example of a typical procedure. 

Representative Method Ion-selective electrodes find application in numerous quantitative analyses, each of which has its own unique considerations. The following procedure for the analysis of fluoride in toothpaste provides an instructive example. 

Representative Method Every controlled-potential or controlled-current coulo-metric method has its own unique considerations. Nevertheless, the following procedure for the determination of dichromate by a coulometric redox titration provides an instructive example. 

An emphasis on practical applications. Throughout the text applications from organic chemistry, inorganic chemistry, environmental chemistry, clinical chemistry, and biochemistry are used in worked examples, representative methods, and end-of-chapter problems. 

Representative methods link theory with practice. An important feature of this text is the presentation of representative methods. These boxed features present typical analytical procedures in a format that encourages students to think about why the procedure is designed as it is. 

Of the electrical methods, only two representative methods will be considered here. Other electrical methods have been discussed previously, e.g., in Refs. 11 and 96. Capillary methods have been used often and discussed for their sources of errors and are therefore not particularly considered here. 

Fig. 31.7. Biplot of chromatographic retention times in Table 31.2, after column-standardization of the data. Unipolar semi-axes have been drawn through all points representing methods. The particular arrangement of the methods is indicative for the presence of a strong size component in the data.

In the following sections, the nature of chloroacetanilide residues in plants, animal products, water, and soil and the rationale for the analytical methodology that is presented are briefly summarized. Procedures for representative methods are included in detail. The methods presented in this article are among the best available at this time, but analytical technology continues to improve. Future directions for acetanilide residue methodology for environmental monitoring are discussed at the end of the article. 

Residues of alachlor and acetochlor are determined by similar methods involving extraction, hydrolysis to the common aniline moieties, and separation and quantitation by reversed-phase FIPLC with electrochemical detection. The analytical method for acetochlor is included as a representative method for residue determination of alachlor and acetochlor in plant and animal commodities. Propachlor and butachlor residues, both parent and metabolite, are determined by similar analytical methods involving extraction, hydrolysis to common aniline moieties, and separation and quantitation by capillary GC. The analytical method for propachlor is included as a representative method. The details of the analytical methods for acetochlor and propachlor are presented in Sections 4 and 5, respectively. Confirmation of the residue in a crop or... 

COMPARISON OP REPRESENTATIVE METHODS FOR THE CONCENTRATION OF TRACE ORGANIC COMPOUNDS IN HATER... 

There are many other methodologies that can be used to measure end groups of polyesters by NMR. The examples above represent methods that we are using in our own work. 

Simply on the basis of the normal composition of marine organisms, we would expect proteins and peptides to be normal constituents of the dissolved organic carbon in seawater. While free amino acids might be expected as products of enzymic hydrolysis of proteins, the rapid uptake of these compounds by bacteria would lead us to expect that free amino acids would normally constitute a minor part of the dissolved organic pool. This is precisely what we do find the concentration of free amino acids seldom exceeds 150 xg/l in the open ocean. It would be expected that the concentration of combined amino acids would be many times as great. There have been relatively few measurements of proteins and peptides, and most of the measurements were obtained by measuring the free amino acids before and after a hydrolysis step. Representative methods of this type have been described [245-259]. Since these methods are basically free amino acid methods, they will be discussed next in conjunction with those methods. 

Scheme 16 Some representative methods for the synthesis of titanacyclopropanes and titanacyclopropenes.

Hcxanc can be determined in biological fluids and tissues and breath using a variety of analytical methods. Representative methods are summarized in Table 6-1. Most methods utilize gas chromatographic (GC) techniques for determination of -hexane. The three methods used for preparation of biological fluids and tissues for analysis are solvent extraction, direct aqueous injection, and headspace extraction. Breath samples are usually collected on adsorbent traps or in sampling bags or canisters prior to analysis by GC. 

Methods are available for determining 1,4-dichlorobenzene in a variety of environmental matrices. A summary of representative methods is shown in Table 6-2. Validated methods, approved by agencies and organizations such as EPA, ASTM, APHA, and NIOSH, are available for air, water, and solid waste matrices. These methods for analysis of drinking water, waste water, and soil/sediment samples are included in Table 6-2. Many of the methods published by APHA (1995) and ASTM (1994) for water are equivalent to the EPA methods. 

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