Data Collection and Interpretation

To quantitate data in either a computer or an integrator, you must first establish a baseline, then acquire data from an injection, detect peaks, integrate the peaks, and compare the peak integrations to response tables from known amounts of standards compounds. 

Finally, these relative heights or areas are compared with equivalent values obtained from standards curves prepared from known amounts of target compounds to yield values for the amount of each target compound present in the chromatographic injection. Unknowns in the chromatogram can be identified with relative retention times, areas, and heights, but the amount of each present cannot be determined until they are identified, standard curves run, and response factors calculated for each compound. 

Calibration standards can be of two types external standards and internal standards. With external standards, multiple concentrations of the standards are injected, areas are measured, and a calibration curve is platted. Unknown samples are then injected, chromatograms run, and areas are calculated and compared with the calibration curves to determine amounts of each compound present. With internal standards, known amounts of an internal standard are added to each known concentration of standard compound and areas or peak height response factors relative to those of the internal standard are calculated. When unknowns are run, a known amount of internal standard is added to the unknown sample, response factors are calculated relative to the internal standards, and amounts of each unknown present are calculated from the standards calibration factors. Internal standards are usually used to correct for variations in injection size due to different operators and injection techniques. Internal standards can also be used to correct for extraction variation in GC/MS target compound quantitation, this standard is referred to as a surrogate standard. Generally, an internal standard is used for one purpose or the other, not both at the same time. 

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Adapted from "Reverse Osmosis Performance Data Collection and Interpretation," originally presented at the 28th Annual Electric Utility Chemistry Workshop, Champaign, IL, May 2008, and published in "UltraPure Water Journal, www.ultrapurewater.com, April, 2009. 

A9.6.4.7 The Nordic Council of Ministers issued a report (Pederson et al, 1995) entitled Environmental Hazard Classification, that includes information on data collection and interpretation, as well as a section (5.2.8) entitled QSAR estimates of water solubility and acute aquatic toxicity . This section also discusses the estimation of physicochemical properties, including log Kow For the sake of classification purposes, estimation methods are recommended for prediction of minimum acute aquatic toxicity, for ...neutral, organic, non-reactive and non-ionizable compounds such as alcohols, ketones, ethers, alkyl, and aryl halides, and can also be used for aromatic hydrocarbons, halogenated aromatic and aliphatic hydrocarbons as well as sulphides and disulphides, as cited in an earlier OECD Guidance Document (OECD, 1995). The Nordic document also includes diskettes for a computerized application of some of these methods. 

Pedersen, F., H. Tyle, J. R. Niemeldi, B. Guttmann, L. Lander, and A. Wedebrand 1995. Environmental Hazard Classification - data collection and interpretation guide. TemaNord 1995 581... 

For certain flow regimes, it is possible to reduce the number of dimensionless groups necessary to characterize a system by properly combining them. This further simplifies data collection and interpretation in several cases of considerable practical importance as shown in the sections that follow,... 

The author acknowledges his indebtedness to his former co-worker, C. E. Melton, with whom much of the source design and data collection and interpretation were done. The author also thanks R. Baldock, for his encouragement of and interest and help in this work. 

Numerous formal in-house reports and memoranda authored by RJRT R D personnel are cited herein. Many have been published totally or in part in peer-reviewed journals and/or presented totally or in part at scientific conferences (Tobacco Chemists Research Conferences, American Chemical Society Symposia on Tobacco and Smoke, CORESTA Conferences, etc.). Whether published, presented, or neither, copies of all RJRT reports cited are stored in various repositories such as the one in Minnesota. Their contents are available on the Internet address indicated. Experimental procedures used, data collected, and interpretations summarized here are described in detail in the reports cited. 

On this basis, it is necessary to agree with the Galwey s remark [6] that the detection of a compensation effect should no longer be reported as an interesting kinetic result but recognized as a demonstration of serious inadequacies in the experimental and/or computational methods used for the data collection and interpretation. ... 

Equatorial and first layer line intensities of the microtubule fibre diffraction pattern shown In figure 2. The vertical intensity axis is in arbitrary Intensity units. The layer line intensity is very weak compared to the equatorial intensity which makes the mathematical correction for the spread in the angular orientation very difficult. For this reason an alternative method of data collection and interpretation is use as described in the text. 

In addition, the data collection and interpretation process could lead to significantly different results, depending on the data source and the acquisition method (field data, simulator data, HRA modelling, expert ehcitation, operation observation, reporting methods, near misses, performance indicators, accident investigation reports etc.). 

Martinez, A., Byrnes, A.P., 2001. Modeling dielectric-constant values of geologic materials an aid to ground-penetrating radar data collection and interpretation. Kansas Geological Survey, Curr. Res. Earth Sci. BuU. 247, 16 pp. Part I. 

The alignment of data collection and interpretation mechanisms with the defined indicators and targets and... 

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