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41.
H. Fitouri R. Boussaha A. Rebey B. El Jani 《Applied Physics A: Materials Science & Processing》2013,112(3):701-710
Bismuth nanodroplets on GaAs substrate were obtained by metalorganic vapor phase epitaxy (MOVPE). New products have been synthesized when Bi nanodroplets are heated under oxygen atmosphere. The oxidation process of Bi nanodroplets consists of a heating from the room temperature to different oxidation temperatures (350, 500, 600 °C) with a temperature rate of 14 °C/min. The annealing duration was fixed to 30 min. The presence of oxygen in the products was confirmed by energy dispersive X-ray (EDX) measurements using a scanning electron microscope (SEM). SEM images show that Bi microcomposites density decrease and their size increases with increasing annealing temperature. After X-ray diffraction analysis of the products no obvious peaks could be observed. The reflectance spectra of the products were studied in spectral domains ranged from 200 nm to 1100 nm. By fitting the reflectivity signal, we extracted the thickness of the products and their refractive index variation versus wavelength. The results show that the thickness of the samples increases with increasing annealing temperature. The photoluminescence (PL) spectra under excitation at 325 nm shows a broad emission centered at around 1.92 eV. 相似文献
42.
W. Jani und E. Reichardt 《Fresenius' Journal of Analytical Chemistry》1872,11(1):71-73
Ohne Zusammenfassung 相似文献
43.
The nature of metal-metal bonding in group 13 dimetallenes REER (E = Al, Ga, In, Tl; R = H, Me, (t)Bu, Ph) was investigated by use of quantum chemical methods that include HF, second order M?ller-Plesset perturbation theory (MP2), coupled cluster (CCSD(T)), complete active space with (CASPT2) and without (CAS) second order perturbation theory, and two density functionals, namely, B3LYP and M06-2X. The results show that the metal-metal interaction in group 13 dimetallenes stems almost exclusively from static and dynamic electron correlation effects: both dialuminenes and digallenes have an important singlet diradical component in their wave function, whereas the bonding in the heavier diindenes and, in particular, dithallenes is dominated by closed shell metallophilic interactions. The reported calculations represent a systematic attempt to determine the metal and ligand dependent bonding changes in these systems. 相似文献
44.
Abdullin S. Banerjee S. Bellucci L. Charlot C. Denegri D. Dittmar M. Drollinger V. Dubinin M.N. Dzelalija M. Green D. Iasvili I. Ilyin V.A. Kinnunen R. Kunori S. Lassila-Perini K. Lehti S. Mazumdar K. Moortgat F. Muller Th. Nikitenko A. Puljak I. Salmi P. Seez C. Slabospitsky S. Stepanov N. Vidal R. Wu W. Yildiz H.D. Zeyrek M. 《The European Physical Journal C - Particles and Fields》2005,39(2):41-61
The European Physical Journal C - This work summarizes the studies for the Higgs boson searches in CMS at the LHC collider. The main discovery channels are presented and the potential is given for... 相似文献
45.
Equilibrium calculations of Si-doping in GaN are investigated using the Gemini code. The method of the calculation is based on the minimisation of the Gibbs free energy. Experimental growth conditions are used for the calculation. The variables are the amount of the dopant and the temperature. The results show the formation of a solid Si3N4 compound with a certain quantity of the input SiH4, that is the silicon precursor in our MOVPE system. Si3N4 formation can explain the limitation of Si incorporation and the surface roughening as revealed by MOVPE Si doped layers. 相似文献
46.
Detailed theoretical investigations into asphericity in the Fermi surface (FS) and Fermi energy (FE) ofNa1_xKx, Na1_xRbx, and Na1_xCsx binary solid solutions are carried out for the first time. The alloying behavior ofthe K, Rb, and Cs with the Na generates the Fermi surface distortion (FSD) of bce simple metals. The FS of Na-K,Na-Rb, and Na-Cs solid solution is a distorted sphere with the largest deviation along [110]. We have found that theimpact of local-field correction function on FSD is maximun at [100] point and minimum at [111] point. The exchangeand correlation effect is found to suppress the value of FE. 相似文献
47.
Tetyana A Mykhaylyk Stephen Collins Chintan Jani Ian W Hamley 《European Polymer Journal》2004,40(8):1715-1721
The ozone etching of thin films of a commercial polystyrene-polyisoprene-polystyrene (PS-PI-PS) triblock copolymer (Vector 4111) was studied using atomic force microscopy (AFM) and ellipsometry. The major phase of the copolymer consists of PI (82 wt.%) and the copolymer forms a cylindrical structure upon annealing. Moderate ozone doses (1.4% wt/wt) were used to etch the copolymer. This revealed two stages of the ozonation: rapid etching of the PI fragments followed by slow compacting of the remaining PS cylinders. Under certain conditions ozone treatment results in the formation of nanosized grooves in a PS matrix which is suitable for lithographic processes. 相似文献
48.
Polarization effects for the leptonic decays of W± and Z0 are calculated and discussed in collisions with longitudinally polarized proton beams. Numerical examples are given for the CERN collider and Fermilab Tevatron. 相似文献
49.
Electron spin resonance has been used to study three similar, but distinct, S = 1 defects (labelled E″ centers) in high-quality synthetic quartz crystals. These centers are produced by electron irradiation and their concentrations depend on the irradiation temperature, the nature of previous irradiations and thermal anneals, and whether the sample is swept or unswept. The radiation-induced mobility of interstitial alkali ions (Li+ and Na+) correlates with the production of E″ centers. 相似文献
50.
P. Johnson P. Mason H. Muirhead P. Michaelides Ch. Michaelidou G.D. Patel G.W. van Apeldoorn D. Harting D.J. Holthuizen J.M. de Leeuw B.J. Pijlgroms M.M.H.M. Rijssenbeck V. Karimaki M. Korkea-Aho R. Kinnunen J. Tuominiemi G. Ekspong T. Moa S. Nilsson 《Nuclear Physics B》1980,173(1):77-92
Simple inclusive cross sections for interactions at 12 GeV/c are given. The data cover prong cross sections, V0 production and resonances. Separation has been made into annihilation and non-annihilation modes. Some implications of the data are discussed. It is pointed out that the ratios of cross sections for production are independent of incident antiproton momentum in annihilation processes, and that data at the highest available pp energies (ISR) tend to the same value. 相似文献