Quantitative data, instrumental presentation

XPS analyses was performed on a Quantum 2000 Scanning SK Microprobe instrument. For the XPS analyses the samples were mounted on a sample plate, introduced into the XPS chamber and evacuated to <2x10 Pa. Elemental surveys and narrow scans were conducted with A1 KD X-rays on the uncalcined samples after which the temperature was increased to 573 K and 873 K (heating rate = 20 K min" ). Semi-quantitative data were calculated from the survey scans. The peak area ratios reported in this paper are fractions, which were calculated from the areas under the XPS peaks. The narrow scan data were used to determine probable compounds for the Co and C peaks. This was accomplished from a Gauss-Lorenzian peak fit of the appropriate photoelectron peaks. Wide spectra were recorded to obtain a semi-quantitative analyses of all elements present on the surface (except H and He) and high-resolution narrow spectra were recorded to identify the oxidation states and/or compounds. 

The acquisition of quantitative analytical results is the ultimate goal of analytical emission spectroscopy thus the procedures used to obtain these data are important. Read-out devices used with flame emission are usually a visual meter, a digital read-out (voltmeter), or a chart recording. A few instruments are equipped to provide internal adjustment to provide a direct read-out in concentration units, such as /ig/ml. A few basic methods of treating data are presented here. 

During the past year we have replaced the Coherent Model 599-03 by the Coherent Model 599-21. With both dye lasers actively stabilized in frequency, the instrumental resolution could be increased to 1 or 2 MHz. Although the system has not yet operated according to specifications, we have obtained new quantitative data on the linewidth of the central components. It is the purpose of this paper to present these new data. They demonstrate the phenomena of colli-sional narrowing of residual Doppler broadening in four-wave light mixing, as discussed in section 2, and of collision-induced Zeeman coherences, treated in section 3. 

The objective of this test was to present and analyze suitable experimental results for verif ying quantitatively the use of the above-mentioned three corrections with the W-3 correlation for predicting the DNB heat flux in a rod bundle. Uncertainties in the data due to instrument errors and heater rod fabrication tolerances... 

With the introduction of computers and microprocessor-controlled instrumentation, it has become possible to use spectrophotometry to obtain far more accurate determinations of color. The tristimulus values are obtained after integration of the data according to Eqs. (7)—(9). This degree of sophistication permits the use of more advanced methods of color quantitation, such as the 1976 CIE L u v system [41] or other systems not discussed in the present chapter. 

The rotational relaxation of DNA from 1 to 150 ns is due mainly to Brownian torsional (twisting) deformations of the elastic filament. Partial relaxation of the FPA on a 30-ns time scale was observed and qualitatively attributed to torsional deformations already in 1970.(15) However, our quantitative understanding of DNA motions in the 0- to 150-ns time range has come from more accurate time-resolved measurements of the FPA in conjunction with new theory and has developed entirely since 1979. In that year, the first theoretical treatments of FPA relaxation by spontaneous torsional deformations appeared. 16 171 and the first commercial synch-pump dye laser systems were delivered. Experimental confirmation of the predicted FPA decay function and determination of the torsional rigidity of DNA were first reported in 1980.(18) Other labs 19 21" subsequently reported similar results, although their anisotropy formulas were not entirely correct, and they did not so rigorously test the predicted decay function or attempt to fit likely alternatives. The development of new instrumentation, new data analysis techniques, and new theory and their application to different DNAs in various circumstances have continued to advance this field up to the present time. 

The computer not only corrects for background radiation, sample quenching and instrument efficiency, it calculates the statistics for LSC counting as presented by Currie (1). The data outputs are, therefore, more meaningful, because detection and quantitation limits are known. 

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