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71.
J.M. Silveyra G. Vlasák D. Jani?kovi? 《Journal of magnetism and magnetic materials》2010,322(16):2350-1918
Magnetostriction, dilatation and calorimetric measurements were performed on FINEMET type as-quenched and heat treated ribbons. Nb was gradually replaced by Mo in order to study the influence of the refractory elements exchange on several magnetostriction parameters. The results could be correlated with magnetic and structural transformations throughout thermal treatments and assured that the whole series is suitable for technical applications. 相似文献
72.
Results of the studies of the properties like binding energy, the pair distribution function g(r), the structure factor S(q), specific heat at constant volume, velocity autocorrelation function (VACF), radial distribution function, self-diffusion
coefficient and coordination number of alkaline-earth metals (Be, Mg, Ca, Sr and Ba) near melting point using molecular dynamics
(MD) simulation technique using a pseudopotential proposed by us are presented in this article. Good agreement with the experiment
is achieved for the binding energy, pair distribution function and structure factor, and these results compare favourably
with the results obtained by other such calculations, showing the transferability of the pseudopotential used from solid to
liquid environment in the case of alkaline-earth metals. 相似文献
73.
74.
We find a concrete integral formula for the class of generalized Toeplitz operators \(T_a\) in Bergman spaces \(A^p\), \(1<p<\infty \), studied in an earlier work by the authors. The result is extended to little Hankel operators. We give an example of an \(L^2\)-symbol a such that \(T_{|a|} \) fails to be bounded in \(A^2\), although \(T_a : A^2 \rightarrow A^2\) is seen to be bounded by using the generalized definition. We also confirm that the generalized definition coincides with the classical one whenever the latter makes sense. 相似文献
75.
Isotropic Compton profiles of TaC and TaN have been measured for the first time, at an intermediate resolution, using 662 keV γ-radiation. Energy bands, density of states and Fermi surface topology of TaC and TaN have been computed using linear combination of atomic orbitals with density functional theory and full potential linearised augmented plane wave method. Both band structure calculations predict the metallic character of TaC and TaN. The electron momentum densities calculated using various approaches of density functional theory are compared with the present measurements. On the basis of Mulliken’s population, it is also seen that TaC has more covalent bonding than TaN. The optical properties computed using full potential linearised augmented plane wave method are explained in terms of intraband transitions. 相似文献
76.
Song W Marcus DM Abubakar SM Jani E Haw JF 《Journal of the American Chemical Society》2003,125(46):13964-13965
Framework-bound alkoxy groups are well-studied intermediates in zeolite chemistry, but their low stability complicates their spectroscopic study in high-temperature reactions such as alkylation or dealkylation. Taking advantage of the much higher bond strength of Si-O versus C-O, we synthesized trimethylsilylated zeolites by reacting them with phenyltrimethylsilane in a catalytic flow reactor at 648 K. In favorable cases, the reaction accurately titrated the acid sites, and 29Si and 13C MAS NMR spectra of the derivatized catalysts measured at room temperature confirmed the proposed reaction. 相似文献
77.
The diffusion of Vanadium has been studied in V-doped GaAs layers (GaAs:V) grown by Metal-Organic Chemical Vapour Deposition (MOCVD) using secondary ion mass spectroscopy (SIMS). The vanadium (V) concentration profiles of sandwiched structures made of alternatively undoped and V doped GaAs layers have shown a concentration independent diffusion coefficient (DV) for varying V doping levels from 1018 to 1019 cm−3. Measurements of DV at 550, 615 and 680 °C indicate that the temperature dependence of DV can be represented by the Arrhenius equation: cm2 s−1. It is suggested that V diffuses via interstitial sites. 相似文献
78.
79.
Toby D. M. Bell Dr. Sheryll Yap Chintan H. Jani Sheshanath V. Bhosale Dr. Johan Hofkens Prof. Frans C. De Schryver Prof. Steven J. Langford Prof. Kenneth P. Ghiggino Prof. 《化学:亚洲杂志》2009,4(10):1542-1550
The synthesis and photophysics of two new aminopropenyl naphthalene diimide (SANDI) dyes are reported. A general and convenient method for the synthesis of the precursor mono‐, di‐, and tetrabrominated 1,4,5,8‐naphthalene tetracarboxylic dianhydrides is described. The two core‐substituted SANDIs exhibit many of the photophysical properties required for fluorescence labeling applications including high photostability and high fluorescence quantum yields (>0.5) in the visible region of the spectrum. The emission wavelength is sensitive to the number of substituents on the NDI core, and the fluorescence decay times are in the range of ~8–12 ns for both compounds in the solvents investigated. Preliminary fluorescence emission data from single molecules of the compounds embedded in poly(methyl methacrylate) films are also reported and show that single molecules have very low yields of photobleaching, particularly the di‐substituted system. Furthermore, only a small proportion (<10 %) of the single molecules studied display fluorescence intermittencies or “blinks” in their photon trajectory. The compounds appear to be excellent candidates for applications at the single molecule level, for example, as FRET labels. 相似文献
80.
Rajiv?Vaidya Madhavi?Dave S.?S.?Patel S.?G.?PatelEmail author A.?R.?Jani 《Pramana》2004,63(3):611-616
In the present paper an attempt has been made to describe the chemical vapor transport (CVT) technique used for the growth
of molybdenum disulphide (MoS2) single crystals. Iodine (I2) is used as transporting material for this purpose. The energy dispersive analysis by X-ray (EDAX) confirmed the stoichiometry
of the as-grown crystals. The lattice parameters of these crystals were determined from the X-ray diffraction analysis. The
grown crystals were examined under the optical zoom microscope for their surface microstructure study. 相似文献