Detailed Application Notes

The examples below are based on experiences made when adaphng the process analyzer presented in section 4.5 (Equispec Chemical Process Analyzer, Equitech Int l Corporation, New Ellenton, SC, USA) to industrial problems. 

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Britz, D., Digital Simulation in Electrochemistry, Springer-Verlag, Berlin, 1981 and MacDonald, D., Transient Techniques in Electrochemistry, Plenum Press, New York, 1977. Both of these books contain copious details concerning electrochemical simulations. Although these texts are extremely mathematical (as all simulation work has to be), the basic concepts are not too difficult to follow. The application notes to Condecon (see URL on page 301) are also a feast of detail. 

A more detailed description of this work can be found in Application Note... 

Use a Web search engine such as Google to find sites dealing with potentiometric titrators. This search should turn up such companies as Spectralab, Analyticon, Fox Scientific, Brinkmann, Metrohm, Mettler-Toledo, and Thermo Electron. Set your browser to one or two of these and explore the types of titrators that are commercially available. At the sites of two different manufacturers, find application notes or bulletins for determining two analytes by potentiometric titration. For each, list the analyte, the instruments and the reagents that are necessary for the determination, and the expected accuracy and precision of the results. Describe the detailed chemistry behind each determination and the experimental procedure. 

Detailed information can be found in the application notes [7,8] of LKB-Produkter AB (Bromma, Sweden) and of Shlmadzu Co (Kyoto, Japan). From LKB-Produkter AB (Bromma. Sweden) a list of references is available Acta Isotachophoretlca [9]. A more recent review is given by P. Bocek et al. [9a]. Because it is difficult to describe all possible fields of application an analysis is selected that gives a survey of applicable on-line detectors used in our laboratory and certainly soon to be available in commercial iTP-equipment. 

In summary, a good thermodynamic understanding of the system behavior is absolutely essential to develop and design CSS, PGSS, RESS and GASP applications. Note that we have not addressed the problem of the experimental determination of thermodynamic properties this is discussed, for example, by Bruno [11]. However, a more detailed simulation of phase equilibria of the systems related to these techniques is given by Kikic et al. [12]. 

Acetaminophen for furtiier details. Also reported pX = 3.98 0.01 at I = O.IM (KNO3). The same result was reported in Sirius Technical Application Notes, vol. 2, p. 151 (1995). Sirius Analytical Instruments Ltd., Forest Row, East Sussex, RH18 5DW, UK. NB From extrapolation to 0% DMSO from data in 10.7-58.3 wt% DMSO by the Yasuda-Shedlovsky procedure. Concentration of analyte, 0.64-1.16 mM I = 0.155 M (KCl). 

SPE is used widely for the cleanup and concentration of analytes for analysis using LC, HPLC, and LC-MS, discussed in Chapter 13. As you will see, the phases used in HPLC for the separation of compounds are in many cases identical to the bonded solid phase extractants described here. Detailed examples and applications notes are available from a number of SPE equipment suppliers J.T. Baker (www.jtbaker.com), Supelco (www.sigma-aldrich.com/supelco), and Phenomenex (www.phenomenex.com) are a few of the companies that supply these products. 

Internet World Wide Web Literature Research project. Choose one of the HPLC compound class applications in Section 13.1.7, and use the links in Appendix 13.1 to download manufacturer s application notes, sample chromatograms, and suggested products for their analysis. Write a detailed experimental procedure to separate your chosen compounds. 

Detailed information on the realization of amplifiers for biomedical instrumentation and the availability of commercial products can be found in the references and in the data books and application notes of various manufacturers of integrated circuit amplifiers, such as Burr-Brown, Analog Devices, and Linear Technology Corporation, as well as mamrfacturers of laboratory equipment, such as Biopac Systemy Inc., Gould, and Grass. 

Flame atomic absorption was until recently the most widely used techniques for trace metal analysis, reflecting its ease of use and relative freedom from interferences. Although now superceded in many laboratories by inductively coupled plasma atomic emission spectrometry and inductively coupled plasma mass spectrometry, flame atomic absorption spectrometry still is a very valid option for many applications. The sample, usually in solution, is sprayed into the flame following the generation of an aerosol by means of a nebulizer. The theory of atomic absorption spectrometry (AAS) and details of the basic instrumentation required are described in a previous article. This article briefly reviews the nature of the flames employed in AAS, the specific requirements of the instrumentation for use with flame AAS, and the atomization processes that take place within the flame. An overview is given of possible interferences and various modifications that may provide some practical advantage over conventional flame cells. Finally, a number of application notes for common matrices are given. 

The uranium oxide data in Table 7.8 were collected on a Teledyne Leeman Labs Prodigy DC Arc. The uranium oxide was mixed with a small amount of gallium oxide/cobalt oxide buffer and 125 mg of the buffered sample were analyzed. The prebum time was 4 s, and the elements were determined in a 4-45 s integration time. The details are available in an application note available from Teledyne Leeman Labs, along with other examples of the use of DC arc emission for materials analysis. 

The Unisantis XMF-104 X-ray microanalyzer (Unisantis S.A., www.unisantis.com) was used by researchers at the Institute for Roentgen Optics, Moscow, Russian Federation, to examine nonde-structively the composition of ancient coins from the fourth century BC through the second century AD. The fourth century BC coins were found to be an alloy of 82% Ag/18% Cu, but areas of pure Ag showed the inhomogeneity of the alloy. A drachma coin depicting Alexander was composed of 99% Ag/1% Cu. The XMF-104 system had a 50 W Mo tube, a 2-stage Peltier-cooled compact Si-PIN detector and polycapillary focused X-ray beam with a 50-250 pm focal spot. Spectra, images of the coins, and details are available at www.unisantis.com, application note 605. 

The electrochemical cell would need quartz windows. A typical three-electrode system, with WE, CE, and reference electrode, is used. Eor IR work, the source and spectrometer would have to be suitable and the windows of the cell would have to be IR transparent, for example, CaFj. Suitable materials have been discussed for both techniques in Chapters 4 and 5. Commercial systems are available from BioLogic Science Instruments, Claix, Erance (www.bio-Iogic.info), and from ZAHNER-Elektrik GmbH Co., KG, Kronach, Germany (www.zahner.de). Their websites contain pictures and detailed instrument descriptions as well as a number of application notes and technical notes. 

Measurements of high impedance, i.e., high-resistance and low-capacitance samples, are very demanding. Each potentiostat is characterized by a certain input impedance that limits its applications. One ISO norm, ISO 16773 (parts 1-4) [675], describes in detail equipment calibration and measurement procedures as well as application notes from Gamry [676] and Solarton [677-681]. 

Dipping the entire plate into the matrix solution. This process is a bit laborious because several dipping and drying steps are required, but it is, in our opinion, the method of choice to evenly cover the entire TLC plate with matrix. This technique has been successfully applied with DHB as matrix, but it seems that thus far there were no experiments with other matrix compounds. A detailed description of this approach is available as an application note from the Bruker Daltonics webpage (www.bruker.com). The matrix solution should be as concentrated as possible while the contact time between the TLC plate and the matrix solution should be very short to avoid blurring of the spots. 

The data are room temperature values taken from (1) G.W.C. Kaye and T.H. Laby, Tables of Physical and Chemical Constants, 14th edition, Longman, London (1973), p. 31. (2) M.F. Ashby and D.R.H. Jones, Engineering Materials I, Second edition, Butterworth—Heinemann, Cornwall, UK (1997), p. 34. (3) Tencor Instruments, Film Stress Applications Note 3, Mountain View, CA (1993), where details on original sources of the data can be found. The elastic properties are essentially insensitive to film geometry, but variations in properties could result from variations in processing conditions, impurity content or property measurement techniques. 

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