Materials Literature
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K2Al2B2O7 has been found to be phase matchable for type-1 sum-frequency generation (SFG) at 0.193 microm by mixing the Nd:YAG laser wavelength at 1.0642 microm and the SFG output of the RbTiOAsO4 optical parametric oscillator tuned at 0.2358 microm. An average power of 200 mW at 10 kHz was obtained in a 7-mm-long crys…
Using 2D-LC, a mother PS-b-PI diblock copolymer prepared by anionic polymerization was fractionated into nine fractions differing in the PI and PS block lengths. In this way, PS-b-PIs of the similar molecular weight were obtained. The fractions show composition variation large enough to construct a detailed phase diag…
We describe a model for non-convecting diffusion-controlled solidification of a ternary (three-component) alloy cooled from below at a planar boundary. The modelling extends previous theory for binary alloy solidification by including a conservation equation for the additional solute componentand coupling the conserva…
PTFE latexes with particles in the submicrometer size range were employed as seeds in the emulsifier-free styrene emulsion polymerization to obtain PTFE−polystyrene (PS) core−shell nanospheres. Stable latexes were generally obtained. Neither residual PTFE nor secondary nucleation was observed, thus leading to PTFE−PS…
Group-theoretical methods are widely used in the investigation of phase transitions in crystals. On the one hand, important structural aspects concerning the relation between the lowand the highsymmetry structures follows from the the group±subgroup relations of the space groups G > H describing the symmetry of the tw…
Colloidal crystal templates were used to synthesize three-dimensionally ordered macroporous sulfated zirconia catalysts with pore diameters of ∼300 nm and less. Ordered arrays of uniformly sized poly(methyl methacrylate) latex spheres were infiltrated with clear precursor solutions containing varying SO 4 /Zr molar ra…
Water-soluble tiopronin monolayer-protected silver clusters (Ag MPCs), with 1.6 nm average diameter cores, exhibit visible luminescence at 500 nm with a quantum yield estimated near 10 -4 when excited at 400 nm. The Ag MPCs become organic-soluble upon conversion to poly(ethylene glycol) quaternary ammonium salts of th…
The interaction of an iron atom with a single-wall carbon nanotube is investigated using spin-polarized total-energy first-principles calculations. A systematic study for the atom approaching the tube surface, both from outside and inside, is presented for several configurations to determine the equilibrium distances…
The autoassembly process of copper-oxalate dimers and Keggin type polyoxometalates leads to the first example of a new family of organic-inorganic hybrids, K(14)[(Cu(2)(bpy)(2)(mu-ox))(SiW(11)O(39)Cu(H(2)O))](2)[SiW(11)O(39)Cu(H(2)O)]. approximately 55H(2)O. This compound crystallizes in the monoclinic space group C2/…
The nonlinear viscoelastic properties for a series of intercalated nanocomposites of an organically modified montmorillonite and a disordered styrene−isoprene diblock copolymer are reported. The linear-to-nonlinear transition for stress relaxation measurements, the applicability of time−strain separability, and the as…
This communication describes the first preparation of highly ordered large-pore hexagonal periodic mesoporous organosilicas (PMOs) using triblock copolymer P123 as the template and inorganic salts as the auxiliary agents under strongly acidic conditions. The long-range structural order of the PMOs results from the enh…
An unusual enhancement of photoluminescence from CdSe nanocrystals (NCs) dispersed in air-saturated CHCl 3 was observed as a function of time. Within two weeks, for samples kept in the dark, the photoluminescence intensity increased by as much as a factor of 6, based on the peak height, with no change in peak position…
The spherical Lindquist type polyoxometalate, Mo(6)O(19)(2)(-), has been used as a noncoordinating anionic template for the construction of novel three-dimensional lanthanide-aromatic monocarboxylate dimer supramolecular networks [Ln(2)(DNBA)(4)(DMF)(8)][Mo(6)O(19)] (Ln = La 1, Ce 2, and Eu 3, DNBA = 3,5-dinitrobenzoa…
Ultrafast optical pump of exciton resonance in single quantum dot by an elliptically polarized laser pulse is described by the non-Markov balance equations. Population and spin dynamics are investigated and spin-dependent Rabi oscillations are considered for the case of a flat quantum dot, with the lateral size greate…
We study current-driven magnetization switching in nanofabricated Ni84Fe16/Cu/Ni84Fe16 trilayers at 295 K and 4.2 K. The shape of the hysteretic switching diagram at low magnetic field changes from 295 K to 4.2 K. The reversible behavior at higher field involves two phenomena, a threshold current for magnetic excitati…
The electronic band gaps measured in fluorescence spectroscopy on individual single wall carbon nanotubes isolated within micelles show significant deviations from the predictions of one electron band theory. We resolve this problem by developing a theory of the electron-hole interaction in the photoexcited states. Th…
The mapping transformation technique is applied to obtain exact results for the spin-1/2 and spin-S (S=1/2,1) Ising-Heisenberg antiferromagnetic chain in the presence of an external magnetic field. Within this scheme, a field-induced first-order metamagnetic transition resulting in multiplateau magnetization curves, i…
A floristic and taxonomic survey was made of the diatom communities of sediments and microbial mats in 66 freshwater and saline lakes and pools in the Larsemann Hills, Rauer Islands and Bølingen Islands (continental eastern Antarctica). A total of 31 taxa were distinguished, 10 of which could not be identified to spec…
In this paper, we present Mie coefficients of double-layered sphere and consider the scattering problem, including the topics on field distribution, electromagnetic cross section, extinction spectra as well as some potential peculiar properties arising from the presence of left-handed media. The formulation presented…
Superhydrophobic surfaces generate very high contact angles as a result of their microstructure. The impact of a water drop on such a surface shows unusual features, such as total rebound at low impact speed. We report experimental and numerical investigations of the impact of approximately spherical water drops. The…