Macro analysis

II.4 SEMIMICRO APPARATUS AND SEMIMICRO ANALYTICAL OPERATIONS The essential technique of semimicro analysis does not differ very greatly from that of macro analysis. Since volumes of the order of 1 ml are dealt with, the scale of the apparatus is reduced it may be said at once that as soon as the simple technique has been acquired and mastered, the student will find it just as easy to manipulate these small volumes and quantities as to work with larger volumes and quantities in ordinary test-tubes (150 x20 mm) and related apparatus. The various operations occupy less time and the consumption of chemicals and glassware is reduced considerably these two factors are of great importance when time and money are limited. Particular care must be directed to having both the apparatus and the working bench scrupulously clean. 

In micro analysis the scale of operations is reduced by a factor of 0-01 as compared with macro analysis. Thus whereas in macro analysis the weights and volumes for analysis are 0-5—1 g and about 10 ml, and in semimicro analysis 50 mg and 1 ml respectively, in micro analysis the corresponding quantities are about 5 mg and 0-1 ml. Micro analysis is sometimes termed milligram analysis to indicate the order of weight of the sample employed. It must be pointed out that whilst the weight of the sample for analysis has been reduced, the ratio of weight to volume has been retained and in consequence the concentration of the individual ions, and other species, is maintained. A special... 

The actual spotting is the fundamental operation in spot test analysis, but it is not always the only manipulation involved. Preliminary preparation is usually necessary to produce the correct reaction conditions. The preparation may involve some of the operations of macro analysis on a diminished scale (compare Section II.5), but it may also utilize certain operations and apparatus peculiar to spot test analysis. An account of the latter forms the subject matter of the present section. 

The reagent (for macro analysis) consists of a 0-5 per cent solution of /7-nitrobenzene-azo-resorcinol in 0 2m sodium hydroxide. 

Note that the order here is reversed, i.e. anions are tested for first, followed by tests for cations. Experience has shown that once the preliminary tests are carried out, considerable information is collected about the presence or absence of certain anions, and it is worthwhile to carry on with anion testing at this stage, always keeping in mind the results obtained by the preliminary tests. The systematic analysis for cations follows this, based again on the separation of each single cation as in macro analysis, and on specific tests carried out after the separation of the cations. 

Macro analysis is the term used when referring to situations where there is a significant amount of sample used in the test. 

However, in practice one finds that in different laboratories, the actual quantity of sample being tested e.g. for macro analysis) will vary enormously. 

The size of the sample is often used to classify the type of analysis performed. As shown in Figure 8-1, the term macro analysis is used for samples of mass more than 0.1 g. A semimicro analysis is performed on a sample in the range of 0.01 to O.lg, while the samples for a micro analysis are in the range 10 to 10 g. For samples whose mass is lower than 10 g, the term ultramicro analysis is sometimes used. 

From the classification in Figure 8-1, we see that the analysis of a 1-g sample of soil for a suspected pollutant would be called a macro analysis, while that of a 5-mg sample of a powder suspected to be an illicit drug would be a micro analysis. A typical analytical laboratory handles samples ranging from the macro size to the micro and even ultramicro size. Techniques for handling very small samples are quite different from those for treating macro samples. 

Qualitative analysis may be carried out on various scales. In macro analysis the quantity of the substance employed is 0.1 to 0.5 g and the volume taken for analysis is about 20 ml. In what is usually termed semimicro analysis these quantities are reduced by a factor of 10-20, i.e. about... 

The objective of all site selections is to turn a property or an existing facility into a weapon of competitive advantage. As Figure 1 indicates, an organization must transition from a big-picture analysis of its strategies and mission (macro analysis), to an assessment of addressable locations (micro analysis), to the construction phase. Though construction can happen without the comprehensive analysis discussed in this chapter, competitive advantage is rare when the upfront evaluation work is not done completely. 

As Figure 2 illustrates, the macro analysis methodology is comprised of five parts ... 

How does customer satisfaction factor into the macro analysis stage of site selection Beyond product quality and price, it impacts such processes and methodologies as ... 

Once the big picture has been analyzed and a macro analysis developed, the microlevel work, in which a specific site must be chosen, begins. This is illustrated in Figure 5. 

Once the general area for site selection has been determined by means of the macro analysis, the selection team should identity specific communities within that area for serious consideration. Since each community will interpret and administer legislation and government mandated/funded programs differently, the site-selection team must take special care to assess each community against company criteria and objectives. The team must therefore view and evaluate communities as they are likely to exist when the proposed facUity comes on-line. 

Hawley, J.M., 2000. Textile recycling as a system a micro/macro analysis. J. Earn. Consum. 

Non-destructive optical analysis offers an instantaneous in-line measurement of concentration. NIR spectroscopy fits well into the list of technologies suitable for process analysis it is fast, precise and non-destructive. When used properly it is also accurate for macro-analysis of major chemical composition parameters or contaminants. Its methodology includes the use of quantitative and qualitative chemometric techniques. In near-infrared, due to the generally much lower absorption coefficients of most combination and overtone bands with respect to the fundamental vibrations of mid-IR, undiluted materials can be analysed in situ in many cases through reasonable path lengths. Process control using NIRS has developed as from about 1980. 

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