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Support of laboratory accreditation in Central and Eastern Europe by preliminary assessment
(Springer-Verlag, 2004)
The development of a competent and reliable network of accredited laboratories represents one, among other, important means of removal of technical barriers to trade. The achievement of the goal "tested once-accepted ...
Influence of nonparabolicity on tunneling times in semiconductor structures
(Elsevier Science Bv, Amsterdam, 2007)
Tunneling of a particle with energy-dependent effective mass through one-dimensional potential barrier is considered. For an arbitrary potential shape we find general relations between phase, group and dwell times, and ...
Group delay in semiconductor structures with energy dependent effective mass
(Polish Acad Sciences Inst Physics, Warsaw, 2007)
We investigate tunneling times of a particle with energy dependent effective mass for a one-dimensional real potential. General relations between phase, group and dwell times are obtained for a desired potential shape. For ...
Optimization of arsenic behavior during concentrate roasting process
(CHISA 2006 - 17th International Congress of Chemical and Process Engineering, 2006)
Copper concentrates almost always contain certain quantity of arsenic, from 0.01-1%. Domestic concentrates processed in Bor Smelting Plant usually contain small quantity of arsenic (0.05-0.15%) except from Bor concentrate ...
Preparation of a-TCP cements from calcium deficient hydroxyapatite obtained by hydrothermal method
(Trans Tech Publications Ltd, Durnten-Zurich, 2006)
In this paper the synthesis of bioactive cement based on al-Ca-3(PO4)(2) (a-TCP) and calcium deficient hydroxyapatite (CDHAp), obtained by hydrothermal method from CaCl2, EDTA, NaH(2)PO(4)(.)12H(2)O and urea at 160 degrees ...
Kinetics of sunflower oil methanolysis catalyzed by calcium oxide
(Elsevier, 2009)
The methanolysis of sunflower oil was studied in the presence of CaO previously calcined at various temperatures and the optimal temperature for CaO calcination was determined. The sigmoidal process kinetics was explained ...
First principle calculations of alkali hydride electronic structures
(Journal of Physics: Condensed Matter, 2007)
Electronic structure, volume optimization, bulk moduli, elastic constants, and frequencies of the transversal optical vibrations in LiH, NaH, KH, RbH, and CsH are calculated using the full potential augmented plane wave ...
Influence of synthesis parameters on the particle sizes of nanostructured calcium-hydroxyapatite
(13th international Symposium on Ceramics in Medicine (BIOCERAMICS), 2001)
In this paper the synthesis of biocompatible calcium-hydroxyapatite particles, chemically and morphologically similar to the mineral particles in human bones, is presented. The influence of synthesis parameters: temperature, ...
Processing of ferroelectric thin layers of barium titanate by the sol-gel method
(Physics and Chemistry of Glasses, 2005)
The influence of various processing parameters is investigated during sol formation (metal precursors: titanium (IV) butoxide, barium hydroxide, barium acetate; pH of sol solution; type and amount of stabiliser and solvent; ...