Material characteristic properties Measurement errors

Many of the data published today are either erroneous or apply to inadequately characterized materials. Unrecognized systematic errors are frequently present in the measurement process, and consequently the data do not represent the property purportedly measured within the stated uncertainty. In other instances, the property measured is especially sensitive to unreported characteristics of the material. For example, the transport properties of pure metals and crystalline dielectric solids at low temperatures are determined almost entirely by the physical and chemical defects in them, rather than by their chemical or generic identification, such as copper, aluminum, etc. Great care must be exercised to characterize such materials, if reported data are to have any usefulness. Both the study of systematic errors and specimen characterization are of the utmost importance to the reliability and usefulness of data. This paper only considers the use of standard reference materials (SRMs) to reduce systematic errors in the measuring system. The problem of insufficient material characterization is an extensive subject in itself and will not be discussed further here. 

What makes a nanoparticle a nanoparticle Definitions of the size ranges for molecules, nanoparticles, and macroscopic solids must be compound specific. However, a useful upper limit for nanoparticles is the size at which one of its properties deviates from the value for the equivalent bulk material by an amount that is significantly larger than the error of the method used to make the measurement (a few percent). In practice, some characteristic will probably be different enough to warrant description as a hanoparticle if it is less than a few tens of nanometers in diameter, and perhaps less than a fraction of a micron in diameter. 

On the one hand, reasons causing the errors appearance are inseparably connected to the nonideality of the physical and electrochemical characteristics of the elements of zirconia gas sensors and to the relative inconstancy of their working conditions. This follows the fact that the measurement process distorts the sideline physical and chemical effects subordinate to the strict enough appropriateness. The clear example of this can be represented by the temperature dependence of physical and electrochemical properties of the SE materials. 

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