Materials Literature
按标题、摘要、年份、主题和来源检索公开元数据。结果保留作者、摘要、分类与原始来源链接。
A series of pyridinium-conjugated oligothiophenes is synthesized electrochemically by nucleophilic substitution of the oligothiophene π-radical cation. The nucleophilic reaction is designed on the basis of high reactivity of the π-radical cation of oligothiophene with various pyridine derivatives as nucleophiles. Whil…
The title complex, [Tb(C11H12N2O)6]I3, has essentially the same structure at 160 K as at room temperature, and is clearly centrosymmetric without any disorder, contrary to some proposals regarding the possible mechanism of triboluminescence. Terbium has an octahedral coordination and lies in a position of \overline 3…
The crystal structure of a new polymorphic form of lead(II) selenite (PbSeO 3 ) was solved directly from conventional X-ray powder diffraction data. Direct methods and Rietveld refinement techniques were used for the structure determination. The compound crystallizes in the monoclinic space group P 2 1 / c (no. 14) wi…
A theoretical model is developed for describing phase transition kinetics occurring by nucleation and growth processes. The model treats the case of spatially correlated nuclei and applies to any kind of nucleation function. A stochastic approach is employed that gives the fraction of transformed phase as a function o…
35Cl, (79,81)Br, and (127)I NQR (nuclear quadrupole resonance) spectroscopy in conjunction with X-ray crystallography is potentially one of the best ways of characterizing secondary bonding of metal cations such as Ag(+) to halogen donor atoms on the surfaces of very weakly coordinating anions. We have determined the…
Author: Dehm, G. et al.; Genre: Journal Article; Issued: 2002-03; Keywords: MPI für Metallforschung; MPI für Metallforschung; Abt. Arzt; Abt. Arzt; ZWE Dünnschichtlabor; 05-ar_2002; thin film; plasticity; dislocation; interface; Title: Plasticity and interfacial dislocation mechanisms in epitaxial and polycrystalline…
Two strains were included in the protologue of the description of Nephrodiella brevis VISCHER (Xanthophyceae). The re-investigation of the two original strains shows that they represent two different taxa which belong to the genus Neocystis (Chlorophyta, Radiococcaceae). A formerly designated lectotype is shown to be…
Radiococcaceae (Chlorophyta) is a large and widespread family in terrestrial and freshwater habitats. The taxonomy of this family is difficult because no coherent system of generic criteria exists, fact which led to many species transfers from one genus to another with as a consequence many synonyms. Based on traditio…
To understand the exceptionally long fluorescence lifetime of fourfold coordinated CrIV in γ0 Li2MgSiO4 orthosilicate, the structure of this matrix has been refined from neutron diffraction data. Here we also report the crystal growth of Cr:Li2MgSiO4 (low temperature form) by a flux method, and the results of EXAFS an…
Mineral zircon has been considered as a possible medium for luminescence dating. The development of a suitable material for luminescence dating requires detailed knowledge of the processes taking place during, for example, exposure to ionizing radiation, long-term storage, annealing at moderate temperatures, excitatio…
The way in which alignment of hexagonal columnar mesophases depends on molecular structure, film thickness, and surface interactions is investigated. Homeotropic orientation of tapered nonpolymeric and polymeric amphiphilic columnar molecules occurs most readily on carbon substrates. The planar alignment of asymmetric…
Author: Du, K. et al.; Genre: Journal Article; Published in Print: 2002-03; Keywords: MPI für Metallforschung; Abt. Rühle; ZWE Hochspannungs-Mikroskopie; high-resolution transmission electron microscopy; distortion analysis; Title: Lattice distortion analysis directly from high resolution transmission electron microsc…
The reaction of tetracyanoethylene (TCNE) and 7,7,8,8-tetracyano-p-quinodimethane (TCNQ) with Fe(CO)(5) leads to formation of magnetically ordered materials of Fe[TCNE](2) (T(c) = 100 K) and Fe[TCNQ](2) (T(c) = 35 K) composition, respectively. In contrast, the reaction with 1,2-dichloro-5,6-dicyanobenzoquinone (DDQ) l…
Evaporation rates of water and oil from creamed oil-in-water emulsions have been measured under conditions of controlled gas flow. The continuous water phases of the emulsions evaporate at rates equal to that for pure water under the same conditions. The evaporation rates of dispersed oil drops are retarded, relative…
The existence of ether byproducts could be clearly proven for the hyperbranched polymerization of 2,2-bis(hydroxymethyl)propionic acid (bis-MPA) using NMR spectroscopy. Polymerization experiments were performed under standard conditions with different catalysts. The ether structures were identified by characteristic 1…
The structures of hydrogen silsesquioxane based porous low dielectric constant (low- k ) films (XLK) prepared with varying process conditions are characterized using a combination of high-energy ion scattering, X-ray reflectivity, and small-angle neutron scattering. We measure the film thickness, average mass density,…
Abstract The synthesis of second‐generation (G‐2) dendritic polymers of isoprene (I) and styrene (S) was achieved with anionic polymerization high‐vacuum techniques and by performing the following steps: (1) selective reaction of a living chain with the chlorosilane group of 4‐(chlorodimethylsilyl)styrene (a dual‐func…
We report high-resolution specific-heat measurements on the quasi-two-dimensional organic superconductor $\ensuremath{\kappa}\ensuremath{-}(\mathrm{BEDT}\ensuremath{-}\mathrm{TTF}{)}_{2}\mathrm{Cu}(\mathrm{NCS}{)}_{2},$ performed by using a sensitive ac-modulation technique. The main observations are (i) a discontinui…
Highly ( S )-enriched substituted poly(ε-caprolactone)s were synthesized from 4-methyl-ε-caprolactone (4-MeCL) and 4-ethyl-ε-caprolactone (4-EtCL) by lipase Novozym-435 (from Candida antarctica ) catalyzed ring-opening polymerizations. The polymerizations were performed in bulk, thus eliminating the need for solvents…
We report the control of molecular orientation in solid films through self-organization and induced-orientation processes. We synthesized water-soluble cationic 3,4,9,10-perylene diimide ( 1 ) and studied its self-organization in aqueous solution. By UV−vis spectroscopy, H-aggregates of 1 were observed forming in solu…