Materials Literature
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In the context of polymer electronic devices, it is of critical importance to understand the nature of the polymer surfaces and the polymer-electrode interfaces. It has been shown that for conjugated polymers, photoelectron spectroscopy, especially in connection with quantum chemical modeling, provides a maximum amoun…
Magnetic susceptibilities of 8 kinds of 3-(4-R-phenyl)-1,5-diphenyl-6-oxo- and -thioxoverdazyl radical crystals ( p -MDpOV (R = OCH 3 ), p -MeDpOV (R = CH 3 ), p -CyDpOV (R = CN), p -NDpOV (R = NO 2 ), p -MDpTV (R = OCH 3 ), p -MeDpTV (R = CH 3 ), p -CyDpTV (R = CN), and p -NDpTV (R = NO 2 )) were measured between 4.2…
A combined theoretical ab initio and structural database study is presented of the different interactions that allow two-coordinate copper(I) molecules to associate, from weak interactions to chemical bonds, giving rise to different structures.
The pressure dependence of the order-to-disorder transition in a polystyrene/polyisoprene (PS/PI) ( M = 17 000) and a polystyrene/poly(methylphenylsiloxane) (PS/PMPS) ( M = 29 600) diblock copolymer of symmetric composition has been studied using small-angle X-ray scattering. The order−disorder transition is investiga…
The sedimentation of spheres in a Newtonian fluid is experimentally studied under creeping flow conditions. The mean particle settling velocity and the particle velocity fluctuations are measured across the width of the sedimentation cell. We show that there can be a global intrinsic convection of the suspension super…
The iron(II) complexes of two new macrocyclic ligands: [24]RBPyBC (L24), a 24-membered macrocycle containing phenol, pyridine and amino donor groups, and [30]RBBPyBC (L30), a 30-membered macrocycle containing phenol, bipyridine, and amino donor groups, were found to be effective for the hydroxylation of alkanes, inclu…
Monomer and dimer structures of p-nitroaniline have been theoretically optimized both invacuo and in the presence of an electric dipole field by means of abinitio molecular orbital procedures at the Hartree–Fock level of theory with the 6-31G and 6-31+G** basis sets. The electron correlation has been estimated at the…
A series of lanthanide polyoxoanions [LnAs4W40O140]25− (Ln = La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy or Yb) have been prepared from the cryptate anion [NaAs4W40O140]27− and lanthanides and characterized by elemental analysis, 183W NMR, emission spectra. A number of evidences indicate that the lanthanides occupy the central…
Inter- and intra-layer disorder in a representative hard carbon derived from epoxy novolac resin at 1000°C have been investigated by comparing both the elastic structure factor S(Q) and radial distribution function obtained from pulsed neutron time-of-flight measurements with calculations from simple hypothetic system…
It has been estimated that within just ten years, over half of all polyolefins will be made by using metallocene catalysts. This ground-breaking volume from PDL brings together for the first time work from dozens of world-renowned experts on the subject. Fifty chapters of peer-reviewed content offer insights into appl…
With the help of bibliometric mapping techniques, we have developed a methodology of “self-organized” structuring of scientific fields. This methodology is applied to the field of neural network research. We propose a field-definition based on the present situation. This is done by letting the data themselves generate…
M. A. Spackman, Annu. Rep. Prog. Chem., Sect. C: Phys. Chem., 1998, 94, 177 DOI: 10.1039/PC094177
the major factors controtling [he morphological and taxonomie composition of siliceous sponge faunas are sedimentation rate and nutrient supply. In seawater bacteria are most abundant in the upper par[ of [he water column. Towards greater depths bacteria disappear gradually. The bathymetric distribution of filter-feed…
BaSO4 (baryte), SrSO4 (celestine) and CaSO4 (anhydrite) were studied using atomistic simulation techniques and their equilibrium morphologies determined from the calculated surface energies. Monolayer and bilayer growth of strontium sulfate or calcium sulfate on barium sulfate were modelled and the calculated surface…
Measurements of molecular weights, soluble fractions and examination of NMR spectra of bisphenol-A polysulfone, after gamma irradiation in vacuum at 150°C were used to elucidate the mechanism of crosslinking. Excellent agreement was obtained between G(S) and G(X) determined from measurements above and below the gel do…
Silicon, an indirect gap semiconductor, can emit light with 10% efficiency at room temperature, provided that it is in the form of low-dimensional (quantum dots or wires) nanostructures. Porous silicon is the best known example of such nanostructures. The luminescence mechanisms and the relationship between bandgap en…
Abstract The crystal and molecular structure of Sn 2 P 2 Se 6 in the low temperature ferroelectric phase is determined by single crystal X-ray diffraction techniques. These results are compared with the crystal structure of the same compound in the paraelectric phase, which was redetermined at room temperature. In bot…
Three Ni/TiO2 samples have been synthesized by impregnation (sample Ni-i-Ti), adsorption of Ni2+ ions from alkaline media on TiO2 (sample Ni-1-Ti) and on reduced Ni-1-Ti (sample Ni-2-Ti). The samples have been characterized by TPR, IR spectroscopy of adsorbed CO and X-ray diffraction. Impregnation leads to a less homo…
Dimeric ortho-phenyleneindium bromide 1 shows a higher affinity for 1,2-diazines than for 1,3- and 1,4-diazines; as shown by the X-ray crystal structure analysis of the host–guest complex 3 the observed selectivity results from subtle structural variation which can bring the indium p orbitals to converge.
Systems undergoing an equilibrium phase transition from a liquid state to an amorphous solid state exhibit certain universal characteristics. Chief among these are the fraction of particles that are randomly localized and the scaling functions that describe the order parameter and (equivalently) the statistical distri…