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151.
G.?J.?Ruiterkamp M.?A.?HempeniusEmail author H.?Wormeester G.?J.?VancsoEmail author 《Journal of nanoparticle research》2011,13(7):2779-2790
The surface functionalization of rutile titanium dioxide nanoparticles with 1-decylphosphonic acid and diethyl undec-10-enyl
phosphonate in a two-stage process, involving a change in reaction medium, is described. Similarly, 1-decylphosphonic acid
and diethyl 1-decylphosphonate were employed as surface modifiers. The nanoparticles coated in two successive steps formed
stable, transparent dispersions in toluene. Surface functionalization was monitored using thermogravimetric analysis (TGA),
which showed enhanced surface coverage after the second capping step. Incorporation of C=C-terminal surface coupling molecules
in the second stage was directly proved using FTIR. Dynamic light scattering measurements showed that the dual-functionalized
particles possessed a uniform size of around 13 nm. Particle dimensions were further analyzed using atomic force microscopy
(AFM) and transmission electron microscopy (TEM). Transparent nanocomposites were formed by introducing the functionalized
nanoparticles into a poly(benzyl acrylate) matrix. The refractive index of poly(benzyl acrylate) composites, measured by spectroscopic
ellipsometry, increased from 1.57 for the pure polymer to 1.63 for 14.0 vol.% TiO2 at λ = 586 nm. Nanocomposite films with particle weight percentages of up to 30% (9.5 vol.%) showed a high light transmittance
of around 90% at wavelengths above λ = 400 nm. 相似文献
152.
A sea-air oscillator model is studied using the time delay theory.The aim is to find an asymptotic solving method for the El Nio -southern oscillation (ENSO) model.Employing the perturbed method,an asymptotic solution of the corresponding problem is obtained.Thus we can obtain the prognoses of the sea surface temperature (SST) anomaly and the related physical quantities. 相似文献
153.
P. Zaleski K. SzymańskiW. Olszewski M. BiernackaK. Perzyńska D. Satu?aA. Go J. Przewo?nikD.A. Zaj?c M. PylakL. Dobrzyński 《Physica B: Condensed Matter》2011,406(17):3196-3205
The lattice site occupation of 3d-type impurities in Cr3Si doped with Fe, Co and Ni were studied using the Extended X-ray Absorption Fine Structure (EXAFS) technique, X-rays and magnetic susceptibility measurements. The EXAFS measurements were performed particularly carefully on the K-edge of chromium and cobalt. EXAFS data strengthened by simulations of the spectra show unambiguously that the impurities are occupying mostly Cr-sites. The magnetic state of the alloys has been studied theoretically using the Wien2k code. It is observed that if calculations are not carried out on an appropriately fine mesh of points in k-space, one can get the result indicating ferromagnetism although the overall magnetic moment per formula unit is weak. 相似文献
154.
C.?CleffEmail author P.?Gro? L.?Kleinschmidt J.?Epping C.?Fallnich 《Applied physics. B, Lasers and optics》2011,105(4):801-805
High spectral resolution coherent anti-Stokes Raman scattering (CARS) spectroscopy and microscopy are demonstrated with femtosecond
laser systems. We perform optimal chirping in glass fibers and demonstrate a spectral resolution enhancement to better than
26 cm−1, which is limited by the bandwidth of the measured resonances. Considering the convolution with the resonance bandwidth this
corresponds to a spectral resolution of approximately 2.5 cm−1, which is an enhancement by a factor of 165 with respect to the use of bandwidth-limited pulses. In microscopic imaging,
a water background suppression of 81.5% is achieved. 相似文献
155.
The present work analyses computationally the flow inside wire enameling dies within the framework of the lubrication theory approximation. Non-Newtonian flow behavior and heat transfer are accounted for as well. It is shown that the developed approach most accurately predicts the momentum and heat fluxes along the wire. As such it is proven as a reliable and computationally efficient tool for the design of flow optimized die shapes. (© 2014 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
156.
We develop an inductive approach to the representation theory of the Yokonuma–Hecke algebra Yd,n(q), based on the study of the spectrum of its Jucys–Murphy elements which are defined here. We give explicit formulas for the irreducible representations of Yd,n(q) in terms of standard d -tableaux; we then use them to obtain a semisimplicity criterion. Finally, we prove the existence of a canonical symmetrising form on Yd,n(q) and calculate the Schur elements with respect to that form. 相似文献
157.
Pierre-Loïc Méliot 《Potential Analysis》2014,40(4):427-509
In this paper, we prove the cut-off phenomenon in total variation distance for the Brownian motions traced on the classical symmetric spaces of compact type, that is to say:
- the classical simple compact Lie groups: special orthogonal groups SO(n), special unitary groups SU(n) and compact symplectic groups USp(n);
- the real, complex and quaternionic Grassmannian varieties (including the real spheres, and the complex or quaternionic projective spaces when q?=?1): SO(p?+?q)/(SO(p)×SO(q)), SU(p?+?q)/S(U(p)×U(q)) and USp(p?+?q)/(USp(p)×USp(q));
- the spaces of real, complex and quaternionic structures: SU(n)/SO(n), SO(2n)/ U(n), SU(2n)/USp(n) and USp(n)/UU(n).
158.
159.
Ion Grosu Lo?c Toupet Gerard Plé Sorin Mager Eugen Mesaros Andreea Varga Elena Bogdan 《Monatshefte für Chemie / Chemical Monthly》2000,54(5):277-286
The synthesis and stereochemistry of new dibrominated spiro-1,3-dioxane derivatives are reported. Investigations by means
of NMR methods and single crystal X-ray diffraction for two compounds revealed the high regio- and diastereoselectivity of
the bromination reaction of some new spiro-1,3-dioxanes and the asymmetric induction of the chiral carbon atom located in
the spiro skeleton. 相似文献
160.