Choice of method

The nature of the calculational bases, that is, the components and conditions of temperature and pressure, are too varied for it to be possible to make absolute recommendations as to the choice of methods. 

Study and Choice of Method for Solving 3D Reconstruction Prohlem in Tomography. 

Attestation of the test procedure is realized with the aim to confirm both the correctness of the choice of method and NDT facilities and fullness of requirements included in the test procedure. Attestation ensures reliability of testing results with required accuracy. 

There is no one best method for describing solvent effects. The choice of method is dependent on the size of the molecule, type of solvent effects being examined, and required accuracy of results. Many of the continuum solvation methods predict solvation energy more accurately for neutral molecules than for ions. The following is a list of preferred methods, with those resulting in the highest accuracy and the least amount of computational effort appearing first ... 

Regardless of the choice of method, excited-state modeling usually requires a multistep process. The typical sequence of steps is ... 

Modeling the lighter main group inorganic compounds is similar to modeling organic compounds. Thus, the choice of method and basis set is nearly identical. The second-row compounds (i.e., sulfur) do have unfilled d orbitals, making it often necessary to use basis sets with d functions. 

Another way to narrow the choice of methods is to consider the scale on which the analysis must be conducted. Three limitations of particular importance are the amount of sample available for the analysis, the concentration of analyte in the sample, and the absolute amount of analyte needed to obtain a measurable signal. The first and second limitations define the scale of operations shown in Figure 3.6 the last limitation positions a method within the scale of operations. ... 

Potassium Chloride. The principal ore encountered in the U.S. and Canadian mines is sylvinite [12174-64-0] a mechanical mixture of KCl and NaCl. Three beneficiation methods used for producing fertilizer grades of KCl ate thermal dissolution, heavy media separation, and flotation (qv). The choice of method depends on factors such as grade and type of ore, local energy sources, amount of clay present, and local fuel and water availabiUty and costs. 

Because of the increa sing worldwide interest and demand for simple, effective, and inexpensive female sterilisation, a variety of procedures and methods have been developed. These approaches differ whether they are performed postpartum, postabortum, or in interval situations. The choice of methods also largely depends upon the physician s prior training, knowledge, and experience. Excellent reviews have been written on sterilisation (98). 

Choice of Method. Numerous enzyme immobilization techniques have been described in the Hterature comprehensive books on this and related subjects, including industrial appHcations, are available (33—36). The more general techniques and some selection criteria are included herein. 

In this section, three methods for calculating the blast parameters of pressure vessel bursts and BLEVEs will be presented. All methods are related that is, one basic method and two variations are presented. The choice of method depends upon phase of the vessel s contents and distance to the blast wave s target, as illustrated in Figure 6.19. 

World production of HCl is of the order of 10 million tonnes pa, thus making it one of the largest volume chemicals to be manufactured. Four major processes account for the bulk of HCl produced, the choice of method invariably being dictated by the ready availability of the particular starting materials, the need for the co-products, or simply the availability of by-product HCl which can be recovered as part of an integrated process,... 

The investigator s choice of method (semi-empirical or ab initio) hinges on a number of factors, one of which is simple practicality concerning both time and expense. Semi-empirical methods usually give reasonable molecular structures and thermodynamic values at a fraction of the cost of ab initio calculations. Furthermore, molecular structures calculated by semi-empirical methods are the starting point for more complex ab initio calculations. 

The choice of method from available resources depends largely upon the properties of the material to be analyzed, the basic significance or physical wearing of the measurement, and the purpose for which the information is required. For example, failure to disperse the particles as discrete entities is the biggest single problem in all size analysis methods that depend on individual particulate behavior. With microscopic techniques particles must be dispersed on the slide to permit observation of individual particles, and in sedimentation techniques the material must be suspended in the fluid so that the particles behave as individuals and not as floes. 

To summarize then, the choice of method should be dictated by the real needs of the submitter of the sample and not by the fanciness of the available instrumentation. 

The choice of method will depend on what information is available and how accurate and detailed the estimate mnst be. ... 

The choice of method used is often facilitated or constrained by the information available. In the absence of structural information on target, if one or more active small molecules are known, LBVS or PHBVS are feasible. If no active compounds are known, but an experimental or computational model of the protein structure is available, SBVS can be considered. If both active compounds and target structure are available, one or more appropriate methods can be applied, or multiple methods combined. 

Wide additive concentration range (restricting the analytical choice of method)... 

The choice of method for a particular application should take into account this categorisation, as well as the precision and accuracy required. This chapter mainly deals with bulk analysis and speciation. 

For the industrial chemist, faced with efficiency requirements, full awareness of the rapidly changing analytical environment is essential budget constraints (and not only these) determine the need for a well-balanced choice of method and equipment. 

Although the novel AR protocol using citraconic anhydride improved the intensity of IHC on FFPE tissue sections for more than half of the antibodies tested, compared to that achieved by other conventional AR protocols, not all antibodies benefitted, which would argue that the citraconic anhydride method does not serve as a truly universal AR protocol. Indeed, many investigators (Table 1.2) have concluded that different antigens may require different specific AR protocols. In this respect, the test battery is a convenient and cost-effective method for assessing the appropriate AR protocol.2,8 Nevertheless, the present data certainly support inclusion of the citraconic anhydride AR method in such a test battery. With respect to the two heating temperatures for citraconic anhydride, the ultimate choice of method for any laboratory may depend on the equipment available. 

Anodic hydroxylation/methoxylation of furans has an exact chemical counterpart in the well-known bromine/methanol reaction, and the choice of method is not always easily made. One can compare the two methods particularly easily in syntheses of the flavoring component, the pyrone maltol 121, from the furan 122 since one group used the electrolytic method299 and another the chemical method.300... 

There are a number of things to consider, but the most important is understanding the needs of the customer. Is the total sugar content of the product required or the lactose content The level of uncertainty in the result that is acceptable also helps focus on the choice of method. Once the method is chosen and validated, it is then important to ensure that all of the equipment is available and in a proper state of calibration. Then, all that remains is to have sufficient trained staff to carry out the analysis. Once the experimental results have been obtained and the data treatment is complete, the report can be written. The report also has to meet the customer requirements and should be written in an unambiguous way which is clear to the non-specialist. 

Hence, the choice of method and the validation of the method selected become increasingly more critical for those analyses resulting in actions towards the bottom of the list than for those at the top. You now need to pause to consider what the consequences of poor analytical work could be in your own particular job. Do not forget to include longer-term implications as well as the immediate problems. Poor or wrong data also result in the loss of reputation - customers who never come back. 

What factors will influence your choice of method List the factors that could be used to distinguish one method from another. 

The choice of method depends on the purpose for which the analysis is being performed. The customer requesting the analysis may specify the method to be used. Even in this situation, it is the responsibility of the laboratory to demonstrate that the method is capable of producing results that are reliable. When no method is specified the points to consider have already been identified in Section 4.2. The acceptable level of measurement uncertainty specified or implied will, to a certain extent, set the precision and bias levels. All of the topics covered in the following sections may be crucial, depending on the purpose of the analysis, and should appear on your list. 

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