Search Results

You are looking at 1 - 10 of 889 items for :

  • "reference materials" x
  • Refine by Access: All Content x
Clear All

Abstract  

Results of a literature search on thermal analysis reference materials are listed

Restricted access

Production of gaseous matrix-free reference materials

Application of thermoanalytical techniques

Journal of Thermal Analysis and Calorimetry
Authors: A. Świtaj-Zawadka, P. Konieczka, J. Biernat, Y. Takao, K. Mita, S. Komar, M. Wesołowski, A. Przyjazny, and J. Namieśnik

Abstract  

Reference materials are used in every laboratory in order to assure the appropriate quality of analytical results. The production of reference materials is not an easy task especially in the case of gaseous, toxic and malodorous compounds. Thermal decomposition of immobilized compounds is a convenient way for the generation of those kinds of mixtures. Temperature is an important variable in this process. In this case, thermoanalytical techniques (thermogravimetry and differential scanning calorimetry (TG-DSC)) and scanning electron microscopy (SEM) were used for checking the temperature range which had been previously determined using thermal desorber-gas chromatograph-flame ionization detector (TD-GC-FID) system.

Restricted access
Journal of Thermal Analysis and Calorimetry
Authors: E. Charsley, C. Earnest, P. Gallagher, and M. Richardson

Abstract  

The ICTAC Committee on Standardisation has formed a Task Group to investigate the suitability of the ICTAC Certified Reference Materials for DTA, covering the temperature range 450°–1100°C, for accurate temperature calibration purposes and to evaluate their potential as enthalpy calibrants for DTA and DSC equipment. This paper reports the results of preliminary round-robin studies on barium carbonate and strontium carbonate, using a dual-point calibration method based on the melting points of aluminium and gold. In addition the fusion of ICTAC potassium sulphate has been investigated as a possible calibration transition.

Restricted access

Abstract  

Fourteen organic compounds, 1-pentene, 2-methylbutane, 2-methyl-1,3-butadiene (isoprene),n-pentane, 2-chloropropane, ethyl alcohol, 2,2,4-trimethylpentane,n-hexane,n-hepatane, 1,3-difluorobenzene, 1,2-dichloroethane, hexafluorobenzene, cyclohexane and diphenyl ether, as new reference materials for energy and temperature calibrations of differential thermal analysers (DTA) and differential scanning calorimeters (DSC) in the temperature range 100–300 K, were investigated. The purities, triple point and transition temperatures, fusion and transition enthalpies of these compounds were measured using a low-temperature DTA apparatus developed by the CTM of the CNRS in Marseille. The results obtained were compared with those produced by adiabatic precision calorimetry. Our data are in good agreement with literature values. Enthalpies of fusion and transition, triple point and transition temperatures are reproduced within ±1% and ±0.1K, respectively.

Restricted access
Journal of Thermal Analysis and Calorimetry
Authors: Eveline De Robertis, Gabriela F. Moreira, Raigna A. Silva, and Carlos A. Achete

for thermal behavior studies, since by the standard method for such determinations the major drawback is the time of analysis. In this work, our intention is verify the thermal behavior of two standard reference materials (SRM) using DSC, such

Restricted access

Introduction Quality initiatives, such as ISO16949, require the calibration of apparatus using certified and traceable reference materials [ 1 ]. In calorimetry, standard methods and reference materials exist for the

Restricted access

Abstract  

INAA results of 11 standard reference materials used in archaeometric investigations of pottery as well as in environmental analysis are presented. The values obtained for 24 elements are compared with the certificate values as well as with the analytical data of other investigators. The accuracy of analysis is discussed.

Restricted access

Abstract  

For preparation of a multielement lichen reference material for environmental studies, 25 kg of the epyphitic lichen Evernia prunastri (L.) Ach. was collected in unpolluted regions of Portugal. The lichen was removed from Cistus ladanifer and Quercus spp. The material was ground to a mesh size 125 m. The material homogeneity was evaluated by determining Na, K, Mn, Br, As, La and Sm on two samples of 100 mg taken at each of 20 locations of the bulk material; the locations were randomly chosen. The k0-based INAA was used. The material is homogeneous for fractions 100 mg, as shown by the evaluation of the heterogeneity of the subsampling operation in the 20 locations and by the results of a one-way analysis of variance for the data obtained. The composition of Evernia prunastri varies neither with the region where it grows nor with the date of collection. This work was accomplished under contract with the IAEA.

Restricted access

Eight inorganic substances recommended by ICTA as temperature standard reference materials for DTA and DSC were studied: KNO3, KClO4, Ag2SO4, K2CrO4, quartz, K2SO4, BaCO3 and SrCO3. The content of pure component in each of these substances was determined by classical chemical analysis. The temperatures and the heats of polymorphic transformations of these substances were measured with a Perkin-Elmer DSC-2 differential scanning calorimeter, and DTA studies were performed on a MOM 1500 D Q-derivatograph. The plot heat of transformation by DSCvs. DTA peak area is advanced as a calibration line for the approximate estimation of quantitative DTA effects. The substances studied will be certified as temperature standard reference materials for use in DTA and DSC.

Restricted access

Abstract  

Fly ash of a waste incineration facility in Berlin, Germany has been found to be a very useful multielement reference material. It can be used for a large number of matrices to be analyzed. It has served as a reference material particularly for environmental multielement analyses. Components which have been recognized as environmental pollutants are present in higher concentration levels than in any other multielement reference material commercially available.

Restricted access