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131.
The aim of this paper is to introduce a new approximate method, namely the Optimal Parametric Iteration Method (OPIM) to provide
an analytical approximate solution to Thomas-Fermi equation. This new iteration approach provides us with a convenient way
to optimally control the convergence of the approximate solution. A good agreement between the obtained solution and some
well-known results has been demonstrated. The proposed technique can be easily applied to handle other strongly nonlinear
problems. 相似文献
132.
Marin Cernea Mihail Secu Corina Elisabeta Secu Mihaela Baibarac Bogdan S. Vasile 《Journal of nanoparticle research》2011,13(1):77-85
In this study, we report on the nanocrystalline powders of TiO2 and Fe-doped TiO2 (anatase and rutile phases) prepared by sol–gel method. The X-ray diffraction and Raman spectroscopy measurements indicated
the presence of anatase or rutile phase in nanopowders. TEM micrographs showed 10 and 112 nm average particle sizes for anatase
and rutile, respectively. Furthermore, their thermoluminescence properties were analyzed. 相似文献
133.
Cristina Ileana Covaliu Daniela Berger Cristian Matei Lucian Diamandescu Eugeniu Vasile Camelia Cristea Valentin Ionita Horia Iovu 《Journal of nanoparticle research》2011,13(11):6169-6180
This study reports a two-steps route for obtaining magnetic nanoparticles–polysaccharide hybrid materials consisting of Fe3O4, NiFe2O4 and CuFe2O4 nanoparticles synthesis by coprecipitation method in the presence of a soft template followed by coating of ferrite nanoparticles of 8–10-nm size range with polysaccharide type polymers—sodium alginate or chitosan. Magnetic oxide nanoparticles and the corresponding hybrid materials were characterized by X-ray diffraction (XRD), Mössbauer spectroscopy, atomic absorption spectroscopy (AAS), FTIR spectroscopy, scanning and transmission electron microscopy (SEM and TEM) and specific surface area measurements. The vibrating sample magnetometry confirms the superparamagnetic properties of the synthesized ferrites and hybrids. Using this route, the percent of magnetic nanoparticles retained in chitosan-based hybrid materials is nearly double in comparison with that of sodium alginate–based materials. The biological activity tests on Escherichia coli ATCC 25922, Pseudomonas aeroginosa ATCC 27853, Staphylococcus aureus ATCC 25923 and Candida scotti microorganisms show the non-toxic properties of prepared hybrid materials. 相似文献
134.
Ionut Ledeti Gabriela Vlase Titus Vlase Nicolae Doca Vasile Bercean Adriana Fulias 《Journal of Thermal Analysis and Calorimetry》2014,115(2):1057-1063
The thermo-physical properties for four rock types (granite, granodiorite, gabbro, and garnet amphibolite) from room temperature to 1,173 K were investigated. Thermal diffusivity and specific heat capacity were measured using the laser-flash technique and heat flux differential scanning calorimetry, respectively. Combined with the density data, rock thermal conductivities were calculated. Rock thermal diffusivity and conductivity decrease as the temperature increases and approach a constant value at high temperatures. At room temperature, the measured thermal conductivity is consistently near or lower than the calculated conductivity using the mineral series model, which suggests that real thermal conduction is more complicated than is depicted in the model. Therefore, in situ measurement remains the best method for accurately obtaining thermal conductivity for rocks. 相似文献
135.
136.
Vasile C. Preda 《Annals of the Institute of Statistical Mathematics》1982,34(1):335-338
Summary The Student distribution is obtained by means of the principle of maximum entropy. 相似文献
137.
C. Vasile G.G. Bumbu G. Bokias G. Staikos Y. Milanos 《光散射学报》2005,17(3):228-230
pacc:7855K Materialsexhibitingthermallyinducedther mothickeningorgellingpropertiesinaqueousso lutions,i.e.presentingasubstantialviscosityin creaseuponheatingareratherexceptional,as mostfluidsarecharacterizedbythewell-known Arrheniusthermothinningbehavi… 相似文献
138.
W.E. Falconer F.J. Disalvo J.E. Griffiths F.A. Stevie W.A. Sunder M.J. Vasile 《Journal of fluorine chemistry》1975,6(6):499-520
Osmium dioxide trifluoride, OsO2F3, has been synthesized thermally by the reaction of OsO4 and OsF6, or of OsOf4 and OsO3F2. The yellow-green material is apparently isomorphous with the monoclinic α-phase of OsO3F2, and although the detailed structure is not known, the Raman spectrum indicates a fluorine bridged polymeric system is likely. OsO2F3 has either a small temperature independent susceptibility or a very small moment μeff < 0.25 μB, the uncertainty being due to the possibility of small amounts of paramagnetic impurity (<2%) in even the best samples prepared. The free molecule is polar, and disproportionates readily at temperatures required to obtain its mass spectrum. Magnetic susceptibilities are reported for OsO3F2, OsOF4, OsO2, OsF5, and OsF6, as well as the new molecule OsO2F3. 相似文献
139.
The thermogravimetric behaviour of the vinyl acetate and α-methylstyrene copolymers of acrylonitrile
Vasile C. Maftei E. Gîlea D. Schneider I. A. 《Journal of Thermal Analysis and Calorimetry》1975,8(3):405-415
Journal of Thermal Analysis and Calorimetry - The influence of the copolymer nature, its comonomer content and the supermolecular structure on the thermal behaviour of the binary vinyl acetate... 相似文献
140.
Mihaela Badea Rodica Olar Dana Marinescu Gina Vasile 《Journal of Thermal Analysis and Calorimetry》2008,92(1):205-208
This paper reports the investigation of the thermal stability of a series of new complexes with mixed ligands of the type
[M(en)(C3H3O2)2]·nH2O ((1) M=Ni, n=2; (2) M=Cu, n=0; (3) M=Zn, n=2; en=ethylenediamine and (C3H3O2)=acrylate anion). The thermal behaviour steps were investigated in a nitrogen flow. The thermal transformations are complex
processes according to TG and DTA curves including dehydration, ethylenediamine elimination as well as acrylate thermolysis.
The final products of decomposition are the most stable metal oxides except for complex (2) that generates metallic copper. 相似文献