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Abstract  

A new terminology of Mössbauer pattern analysis is introduced. In this approach Mössbauer parameters are considered as functions of a number of externally adjusted physical parameters at which the spectrum has been recorded. Our approach can also help to systematize Mössbauer data for the identification of individual physical or chemical species from the corresponding patterns present in the spectrum.

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Summary  

All legitimate scientific disciplines are characterized by: (1) the clear definition of subjects of the study and its corresponding clear-cut name, (2) some accepted postulates, (3) set of research methods, (4) methods of quality control and processing of the obtained information, and (5) specific terminology and definitions. The inaccuracies and uncertainties in medical elementology as a new scientific discipline are discussed and some corresponding statements are made. Another and no less important problem of medical elementology is the critical unsatisfactory reproducibility of data. The complex arrangements required for the harmonization of data acquired for studies in medical elementology are offered. Main strategic aims and tactical tasks of the new scientific discipline are outlined.

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Abstract  

The availability of natural matrix reference materials evaluated for trace element content has resulted in their widespread use as standards (i.e., calibration materials; comparators) for instrumental neutron activation analysis (INAA). Due to the uncertainties associated with their certified values, the limited number available, and the relative matrix independence of INAA, these reference materials are more properly utilized as quality assessment materials, after calibration of the INAA analytical system with true primary standards. Terminology is defined, the use of matrix reference materials to evaluate the analytical system is discussed, techniques for the accurate preparation of primary standards for trace element analyses are reviewed, and necessary precautions in the accurate comparison of samples to standards are presented.

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Abstract  

The minimum amounts or concentrations of an analyte that may be detected or quantified by a specific measurement process (MP) represent fundamental performance characteristics that are vital for planning experiments and designing MPs to meet external specifications. Following many years of conceptual and terminological disarray regarding detection and quantification limits, the International Union of Pure and Applied Chemistry (IUPAC, 1995) and the International Organization for Standardization (ISO, 1997) developed a harmonized position and documents that provide a basis for international consensus on this topic. During the past year, the International Atomic Energy Agency (IAEA) has developed a TECDOC on Quantifying Uncertainty in Nuclear Analytical Measurements that treats "Uncertainty in Measurements Close to Detection Limits" from the perspective of the IUPAC and ISO recommendations. The first part of this article serves as a review of these international developments during the last quinquennium of the twentieth century. Despite the achievement of international consensus on these contentious matters, many challenges remain. One quickly discovers this in the practical world of high stakes, ultra-trace analysis, where complications are introduced by the nature and distribution of the blank, the variance function ( vs. concentration), non-linear models, and hidden algorithms and data evaluation/reporting schemes. Some of these issues are illustrated through a multidisciplinary case study of fossil and biomass burning aerosol at extremely low levels in the polar atmosphere and cryosphere, and by biased reporting practices for "non-detects."

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) 29 – 51 . [9] ICH Guideline Q 2A, Validation of Analytical Procedures: Definition and Terminology (CPMP III/5626/94) . [10] ICH Guideline Q 2B, Validation of Analytical Procedures: Methodology (CPMP/ICH/281/95) .

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2000 IUPAC, Compendium of Chemical Terminology, 2nd edn. (the “Gold Book”). Compiled by A.D. McNaught and A. Wilkinson. Blackwell Scientific

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3261 ICH Guideline Q2A, Validation of Analytical Procedures: Definition and Terminology (CPMP III/5626/94), 1995, Geneva, Switzerland. ICH Guideline Q2B, Validation of

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Abstract  

The enthalpies of formation of 13 calcium silicates, aluminates, alumino-silicates and ferro-alumino-silicates were measured by dissolution calorimetry with the help of a high-temperature Calvet calorimeter. Dissolution experiments were performed in a lead metaborate (2PbO−B2O3) baths at 1173 K. The synthesis of the samples was realized by melting together pure silica, alumina, ferric oxide and calcium carbonate in appropriate ratios. The samples obtained in this way were examined by X-ray diffraction and scanning electronic microscopy. The free lime content was also determined by chemical analysis. The enthalpy of formation of silicates and aluminates obeys two different linear relations with respect to the ratio Ca/X (X=Al or/and Si) except for Ca12Al14O33 which does not exist in its pure form but has to be stabilized by anions as OH or Cl. The data corresponding to the two aluminosilicates are located between these lines. The enthalpy of formation of tricalcium silicate (Ca3SiO5 i.e. C3S according to the Bogue terminology) from dicalcium silicate and lime could be calculated as −6kJ·mol−1. This reaction is the most important one in the industrial process of clinkerization.

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: Methodology (CPMP/ICH/281/95). ICH Guidelines Q2A, Validation of Analytical Procedures: Definition and Terminology (CPMP III/5626/94). K. Ferenczi-Fodor, Z. Végh , and Z. Pap

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Validation of Analytical Methods: Definition and Terminology . International Conference on Harmonization, IFPMA, Geneva, 1994 .

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