Comparative equilibration has been proposed as a methodological approach for determining the hydrogen isotopic composition (deltaD) of non-exchangeable hydrogen in complex organic materials, from feathers to blood and soils. This method depends on using homogenized standards that have been previously calibrated for their deltaD values of non-exchangeable H, that are compositionally similar to u...

Calibration is defined as follows: ‘The set of operations that establish, under specified conditions, the relationship between values of quantities indicated by a measuring instrument or measuring system and the corresponding values realized by standards.’ It is important to recognize at the outset the definition of a ‘calibration’ and to note that the ‘comparison’ applies only to the condition...

Calibration of Optical Time Domain Reflectometer (OTDR) has a crucial role for the accurate determination of fault locations and the accurate calculation of loss budget of long-haul optical fibre links during installation and repair. A comparison has been made between the Egyptian National Institute for Standards (NIS-Egypt) and the National Metrology institute of South Africa (NMISA-South Afri...

National Bureau of Standards Gaithersburg, MD 20899 A description is given of the NBS program in which special photodiodes for the far ultraviolet spectral region (5254 nm) are made available as transfer standards. These detectors are calibrated in terms of quantum efficiency (photoelectrons per incident photon) as a function of wavelength. Descriptions are also given of the calibration princip...

This paper provides an overview of recent efforts at the National Institute of Standards and Technology (NIST) to develop metrology and standards to support general users of instrumented indentation and scan-probe devices. Research directed towards a primary realization of force in the regime below 10 μN, development and characterization of novel compact microforce sensors, scan-probe force cal...

Within the United States, the national standard for radon measurements is embodied in a primary radon measurement system that has been maintained for over 50 years to accurately measure radon (222Rn) against international and national radium (226Ra) standards. In turn, all of the radon measurements made at the National Institute of Standards and Technology (NIST) and the radon transfer calibrat...

The International Organization for Standardization (ISO) decided to establish a Technical Committee 201 (TC201) on the standardization of surface chemical analysis in 1991. Since then, TC201 has published 38 ISO standards. They concern the vocabulary, instrument specifications, pretreatments of specimen, the procedures for analysis, apparatus alignments, measurement conditions, quantification a...