Information about X-ray mass attenuation coefficients in different materials is necessary for accurate X-ray fluorescent analysis. The X-ray mass attenuation coefficients for energy of 7-12keV were measured in biological (Mussel and Oyster tissues, blood, hair, liver, and Cabbage leaves) and geological (Baikal sludge, soil, and Alaskite granite) samples. The measurements were carried out at the EXAFS Station of Siberian Synchrotron Radiation Center (VEPP-3).
View Article and Find Full Text PDFImprovement in the performance of functional nanoscaled devices involves novel materials, more complex structures, and advanced technological processes. The transitions to heavier elements and to thicker layers restrict access to the chemical and physical characterization of the internal material interfaces. Conventional nondestructive characterization techniques such as X-ray photoelectron spectroscopy suffer from sensitivity and quantification restrictions whereas destructive techniques such as ion mass spectrometry may modify the chemical properties of internal interfaces.
View Article and Find Full Text PDFThe aim of the study was to investigate possible changes in the elemental content of small biological tissue samples (with low weight) during the short period of fixation in formalin. Therefore, the effect of the fixation time (4 h to 6 days) was studied on the elemental content of the tissue. Synchrotron radiation X-ray fluorescent analysis (SRXRF) technique was used for the determination of the elemental concentrations.
View Article and Find Full Text PDFTriethylamine borane (TEAB) and He, N(2) or NH(3) were applied as additional reaction gases in the production of BC(x)N(y) layers by low-pressure chemical vapor deposition (LPCVD). These layers were deposited on Si(100) wafers and characterized chemically by X-ray photoelectron spectroscopy (XPS) and synchrotron radiation-based total-reflection X-ray fluorescence analysis combined with near-edge X-ray absorption fine-structure spectroscopy (TXRF-NEXAFS). The composition of the material produced without NH(3) was found to be dominated by B-C bonds with the stoichiometric formula B(2)C(3)N.
View Article and Find Full Text PDFFilms of BC(x)N(y) were produced in a plasma-enhanced chemical vapor deposition process using trimethylborazine as precursor and with H2, He, N2, and NH3, respectively, as auxiliary gas. These films deposited on Si(100) wafers or fused quartz glass substrates were characterized chemically by X-ray photoelectron spectroscopy and by synchrotron radiation-based total-reflection X-ray fluorescence combined with near-edge X-ray absorption fine structure. Independent of the auxiliary gas, the B-N bonds are dominating.
View Article and Find Full Text PDFOn reviewing the data in the literature it is obvious that the differences in the concentrations of certain special elements in human hair for a various number of people are too large to be used as standards or deviations from standards for determining the trace-elemental composition of hair. New questions have arisen with the publication of non-compatible data. What is the distribution of elements on the donor's head area? What is the character of this distribution? Is the distribution function identical for all elements? Hair samples were taken from five points on the heads of six people.
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