Materials Literature
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We have calculated from first principles the electronic structure of 0.5 monolayer upto 5 monolayer thick Fe layers on top of a GaAs (100) surface. We find the Fe magnetic moment to be determined by the Fe-As distance. As segregates to the top of the Fe film, whereas Ga most likely is found within the Fe film. Moreove…
To help provide insight into the remarkable catalytic behavior of the oxygen/silver system for heterogeneous oxidation reactions, purely subsurface oxygen, and structures involving both on-surface and subsurface oxygen, as well as oxidelike structures at the Ag(111) surface have been studied for a wide range of covera…
For exchange-correlation functionals that depend explicitly on the Kohn-Sham orbitals, the potential $V_{\mathrm{xc}σ}(\re)$ must be obtained as the solution of the optimized effective potential (OEP) integral equation. This is very demanding and has limited the use of orbital functionals like exact exchange. We demon…
We examine theoretically electron paramagnetic resonance (EPR) lineshapes as functions of resonance frequency, energy level, and temperature for single crystals of three different kinds of single-molecule nanomagnets (SMMs): Mn$_{12}$ acetate, Fe$_8$Br, and the $S=9/2$ Mn$_4$ compound. We use a density-matrix equation…
Construction of a self-assembled supramolecular macroring that has distances and orientations of porphyrin dimer units in close analogy to those of the natural light-harvesting complexes was achieved. In natural light-harvesting complexes, bacteriochlorophyll-a's are arranged in macroring structures by coordination fr…
The entanglement model, which was proposed previously on the melting point depression of a crystalline low molecular weight diluent in an un-cross-linked amorphous polymer, was modified so as to be consistent with a frozen tube model. In the latter model, the crystallization of the diluent occurs within the entangled…
Additional reflections seemingly leading to a tetragonal fivefold supercell have been observed in a number of melilites. A careful examination of the collected intensity data reveals that this feature is due to the coexistence of two twin domains related by a (120) twin plane. Reflections of the first domain (I) with…
Four fluorescent strain probes with one or two carbazole units placed in the middle of an elastomeric triblock of polystyrene−polyisoprene−polystyrene (SIS) have been prepared and their fluorescence behaviors investigated under strain. The probes were dissolved in commercial SIS type rubbers at low levels of 0.1 wt %.…
The degradation kinetics of polycarbonate [poly(bisphenol A carbonate)] in benzene catalyzed by commercial (rutile) TiO 2 (BET surface area = 11 m 2 /g), anatase TiO 2 (156 m 2 /g), and 1 atom % Pt/TiO 2 (111 m 2 /g), prepared by the solution combustion technique, was investigated at various temperatures (230−280 °C)…
With a highly encumbered manganese porphyrin as catalyst, significant improvements in regioselectivity towards less substituted C-C double bond in diene epoxidation were attained by simply adding organic bases as axial ligand.
We study the nonequilibrium diffusion dynamics of supersonic lattice solitons in a classical chain of atoms with nearest-neighbor interactions coupled to a heat bath. As a specific example we choose an interaction with cubic anharmonicity. The coupling between the system and a thermal bath with a given temperature is…
Adsorption (binding) isotherms of three cationic surfactants (hexadecyl trimethylammonium bromide, dodecyl trimethylammonium bromide, and decyl trimethylammonium bromide) bound to poly(acrylic acid) brushes were determined by means of optical reflectometry. The adsorption occurs reversibly. The shape of the isotherms…
Compared with a monolayer culture, hepatocyte spheroids are known to maintain liver function for long periods. We found that hepatocytes formed spheroids when cultured on polyamidoamine dendrimers modified with fructose. Because galactose is a ligand for the asialoglycoprotein receptor on the hepatocyte cytoplasmic me…
A Comment on the Letter by A. Böker et al., Phys. Rev. Lett. 89, 135502 (2002). The authors of the Letter offer a Reply.Received 21 October 2002DOI:https://doi.org/10.1103/PhysRevLett.90.049601©2003 American Physical Society
Reversible photochemical phase transition behavior of some alkoxy-cyano-substituted diphenylbutadiene liquid crystals has been studied. The EE isomers of these derivatives were found to undergo photoisomerization to yield thermally stable EZ and ZE isomers, which could be transformed back to the EE isomer using light…
The cyclic liquid crystalline trimer TPB-(c)9(3) was investigated by optical retardation and Fréedericksz techniques within a few tens of millikelvins of the superheating limit of the nearly second-order nematic-isotropic phase transition. Both the optical retardation and the Fréedericksz bend threshold voltage are in…
Strong blue upconversion emission has been observed from Y 2 O 3:Tm 3+ phosphors under 632.8-nm excitation, in addition to weaker green and red emissions. All of these emissions, including the red, showed a two-photon intensity dependence on the incident 632.8-nm laser power. The emissions that showed only a one-photo…
Abstract For Abstract see ChemInform Abstract in Full Text.
The cationic [Ln(EDTA-PA2)]+ complexes (EDTA-PA2 = EDTA-bispropylamide) have been characterised by a multinuclear NMR study. 89Y and 13C NMR data indicate the formation of 1 ∶ 1 and 1 ∶ 2 (Ln ∶ ligand) complexes in aqueous solution. The stability constants of these complexes, as determined by potentiometric measuremen…
The nematic order parameter S = 〈P2(cosθ)〉 was calculated from the dielectric relaxation time characterizing the molecular rotation around the short axes using formulae derived by Coffey et al. (W. T. Coffey, Yu. P. Kalmykov and J. P. Waldron, Liq. Cryst., 1995, 18, 677; W. T. Coffey, D. S. F. Crothers, Yu. P. Kalmyko…