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171.
The introduction of cationic surfactant DODA as counterions of [Eu(H2O)2SiW11O39]5- can form a mesoscopic supramolecular assembly of (DODA)4H[Eu(H2O)2SiW11O39], which aggregates into vesicles in chloroform. This POM-based vesicle can be further transferred into three-dimensional microporous architectures under moist air. The present methodology shows that, by combining inorganic chemistry and colloidal surface chemistry, a sequential self-assembling approach based on a series of linkable preorganized building blocks allows access to the fabrication of technological applicably POM-based microsized patterns, alternated with the soft lithographic method. 相似文献
172.
Tong ML Monfort M Juan JM Chen XM Bu XH Ohba M Kitagawa S 《Chemical communications (Cambridge, England)》2005,(2):233-235
Reaction of di-2-pyridyl ketone (dpk) with nickel acetate and azide in the presence of potassium tert-butylate as a catalytic base generates the title compound, which contains the largest [Ni(mu(1,1)-N3)]6 circles in the discrete ferromagnetically-coupled M(II)-azide cluster family, and shows an unprecedented in situ cyanomethylation of ketone. 相似文献
173.
We study sums of bisectorial operators on a Banach space X and show that interpolation spaces between X and D(A) (resp. D(B)) are maximal regularity spaces for the problem Ay + By = x in X. This is applied to the study of regularity properties of the evolution equation u′ + Au = f on
for
or
and the evolution equation u′ + Au = f on [0, 2π] with periodic boundary condition u(0) = u(2π) in
or
相似文献
174.
175.
Korsukov V. E. Ankudinov A. V. Bu?nov A. L. Varkentin M. S. Knyazev S. A. Korsukova M. M. Obidov B. A. Pronin I. I. 《Physics of the Solid State》2010,52(7):1526-1530
The effect of cold rolling, polishing, and thermal annealing conditions on the atomic structure and surface geometry of platinum
foils has been studied. The surface morphology has been analyzed using low-energy electron diffraction, atomic force microscopy,
and scanning tunneling microscopy. The chemical composition of the surface has been evaluated by Auger electron spectroscopy.
It has been demonstrated that a variation in the conditions used for the preparation of the samples makes it possible to produce
surfaces with different degrees of perfection from atomically smooth to rippled, fractal, and diffraction-disordered surfaces. 相似文献
176.
Let 1 ≤ p < ∞. We show that , the Fremlin projective tensor product of ℓp with a Banach lattice X, has the Radon–Nikodym property if and only if X has the Radon–Nikodym property; and that , the Wittstock injective tensor product of ℓp with a Banach lattice X, has the Radon–Nikodym property if and only if X has the Radon–Nikodym property and each positive operator from ℓp' to X is compact, where 1/p +1/p'= 1 and let ℓp' = c0 if p = 1.
The author gratefully acknowledges support from the Office of Naval Research Grant # N00014-03-1-0621 相似文献
177.
Beheshti N Bu H Zhu K Kjøniksen AL Knudsen KD Pamies R Hernandez Cifre JG García de la Torre J Nyström B 《The journal of physical chemistry. B》2006,110(13):6601-6608
The formation of associative networks in semidilute aqueous solutions of hydrophobically modified hydroxyethylcellulose (HM-HEC) is dependent on intermolecular hydrophobic interactions. Addition of hydroxypropyl-beta-cyclodextrin (HP-beta-CD) monomers to the system provides decoupling of these associations via inclusion complex formation with the polymer hydrophobic tails. Results from viscosity, polymer NMR self-diffusion, and dynamic light scattering (DLS) measurements show that the hydrophobic interactions in HM-HEC solutions are effectively suppressed when the level of HP-beta-CD addition increases. Small-angle neutron scattering (SANS) results reveal that the large-scale association complexes in HM-HEC solutions are strongly diminished when the concentration of HP-beta-CD rises. The time correlation data obtained from the DLS experiments unveiled the existence of two relaxation modes: one single exponential at short times followed by a stretched exponential at longer times. The fast mode is always diffusive, whereas the slow mode exhibits progressively stronger wavevector dependence as the intensity of the hydrophobic interactions increases. This feature, as well as the accompanying drop of the stretched exponential beta as the HP-beta-CD concentration decreases, is attributed to enhanced hydrophobic interactions and can be well rationalized in the framework of the coupling model of Ngai. 相似文献
178.
179.
T. ?alkus E. Kazakevi?ius A. Ke?ionis V. Kazlauskien? J. Mi?kinis A. Dindune Z. Kanepe J. Ronis M. Dudek M. Bu?ko J. R. Dygas W. Bogusz A. F. Orliukas 《Ionics》2010,16(7):631-637
Li1.3Al0.15Y0.15Ti1.7(PO4)3 compound was synthesized by solid-state reaction, and ceramics were sintered. The surfaces of the ceramics were investigated by scanning electron microscopy and X-ray photoelectron spectroscopy. Li1.3Al0.15Y0.15Ti1.7(PO4)3 samples were tested in solid galvanic cells Ag|O2+CO2|Li2CO3|Li1.3Al0.15Y0.15Ti1.7(PO4)3|LiMnO2+Mn2O3|O2|Ag. The electromotive force measurements of this cell indicated that investigated samples are practically pure Li-ion conductors. Impedance spectroscopy studies have been performed in the frequency range 10?2–3·109 Hz and temperatures from ?57 °C to 334 °C. Three dispersion regions related to Li+ ionic transport in bulk, grain boundaries of the ceramics and to polarization of electrodes have been found. Total conductivity changes according to Arrhenius law in the studied temperature range, but an anomalous behavior was observed for the bulk conductivity of the ceramics. 相似文献
180.
Deterministic relief dielectric structures to realize phase modulation of surface-plasmon polaritons
We propose a modified effective-refractive-index model for the design of relief dielectric structures on a metal surface to realize phase modulation of surface-plasmon polaritons (SPPs). In this model, the length of the dielectric structure is optimized to reach phase shifting between the SPP waves transmitted through dielectric structure and those directly propagated with the consideration of SPP losses. Specifically, a one-dimensional dielectric Fresnel zone plate is designed by employing the proposed model to demonstrate phase modulation of SPPs for the highest focusing efficiency. 相似文献