Materials Literature
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The anionic ruthenium cluster carbonylates [Ru6C(CO)16]2- or [H2Ru10(CO)25]2- interspersed with bis(triphenylphosphino)iminium counterions (PPN+) are incorporated from solution into the pores of MCM-41 mesoporous silica (3 nanometers in diameter), where they form tightly packed arrays. These arrays were shown by high-…
We present results based on local-spin-density calculations of a computational search for half-metallic (HM) antiferromagnetic (AFM) materials within the class of double-perovskite-structure oxides $\mathrm{La}{M}^{\ensuremath{'}}{M}^{\ensuremath{''}}{\mathrm{O}}_{3}$ that incorporate open-shell $3d$ (or $4d)$ transit…
Purification of single-shell nanotubes is essential if reliable information about their physical and chemical properties is to be obtained. Using the present synthetic techniques, samples typically contain 30% or more amorphous carbon and catalytic metal particle impurities. An extremely simple and efficient method of…
The phase distribution for ceramic coatings formed by microarc oxidation (MAO) on 2024 aluminum alloy was investigated using X‐ray diffraction. The results showed that the ceramic coatings mainly consisted of α‐Al 2 O 3 and γ‐Al 2 O 3 phases. The percentage of α‐Al 2 O 3 gradually increased from the external surface t…
Amide and ester coupling reactions of ω-functionalized monolayer-protected gold cluster molecules (MPCs) are an exceptionally efficient avenue to a diverse variety of polyfunctionalized MPCs starting from a small subset of ω-functionalized materials. In this paper, coupling reactions have been employed to produce 13 M…
The trigonal pyramidal complex [Mn 4 O 3 Cl(O 2 CCH 3 ) 3 (dbm) 3 ], where dbm - is the monoanion of dibenzoylmethane, functions as a single-molecule magnet. High-field EPR data are presented for an oriented microcrystalline sample to characterize the electronic structure of the Mn IV Mn III 3 complex. These data show…
Radiolysis of mixed Au III /Ag I solutions at different dose rates is examined. The progressive evolution with dose of the UV−visible absorption spectra of radiation-induced metal clusters is discussed and compared with those calculated by Mie theory. The clusters have been also observed by transmission electron micro…
We show that linear polarized x-ray-absorption spectroscopy can be used to measure the temperature and thickness dependence of magnetic moments in NiO thin films. We demonstrate that both the long-range order and the nearest-neighbor spin-spin correlations can be revealed. NiO (100) films with thicknesses of 5, 10, an…
The freezing process in lead magnesium niobate (PMN) has been investigated by measurements of the frequency-dependent complex dielectric constant and its third harmonic component. The linear complex dielectric susceptibility was analyzed by a temperature-frequency plot in order to determine the temperature dependence…
Dendrimer-like star polymers, a novel type of molecular architecture, have been synthesized. The architecture of the new polymers resembles that of three-dimensional spherical dendrimers as well as classical star polymers. The controlled structures, based on aliphatic polyesters, are synthesized by a divergent growth…
Cathepsin K (EC 3.4.22.38) is a recently described enzyme that has been shown to cleave type I collagen in its triple helix. The aim of this study was to determine if it also cleaves type II collagen in the triple helix and to identify the helical cleavage site(s) in types I and II collagens. Soluble human and bovine…
Abstract A new class of thermally irreversible and fatigue resistant photochromic molecules named diarylethenes has been developed. Theoretical consideration based on the state correlation diagrams of electrocyclic reactions revealed that the thermal irreversibility is attained by introducing aryl groups that have low…
When a thin film is deposited by physical vapor deposition, with the vapor flux arriving at an oblique angle from the substrate normal, and under conditions of sufficiently limited adatom mobility to create a columnar microstructure, the resulting structure is somewhat porous and grows at an angle inclined toward the…
A general strategy is described for inducing magnetostriction in ferromagnetic martensitic materials. An analysis of domain redistribution caused by a magnetic field is given, and certain relations between material constants that promote this effect are described. These relations suggest a ‘constrained theory of magne…
Graphite nanofibers are a novel material that is produced from the dissociation of carbon-containing gases over selected metal surfaces. The solid consists of very small graphite platelets, 30−500 Å in width, which are stacked in a perfectly arranged conformation. We have discovered that the material is capable of sor…
An aspect of metal oxides, colossal magnetoresistance exhibited by certain manganese oxides, in particular rare-earth manganates of perovskite structure, has received much attention in recent years. Some of these oxides show 100 per cent magnetoresistance, and have potential for technological applications. This text b…
Laser photolysis of nitritomanganese(III) tetraphenylporphyrin, Mn III TPP(ONO) ( 1 ), in degassed toluene gives manganese(II) tetraphenylporphyrin, Mn II TPP ( 2 ), plus NO 2 . The quantum yield, Φ, for the formation of Mn II TPP is dependent on the excitation wavelength: Φ = 0.045 at 355 nm and Φ = 0.0064 at 532 nm.…
Abstract Innovations in crystallographic instrumentation and the rapid development of methods of diffraction measurement have led to a vast improvement in our ability to determine crystal and molecular structure. This up-to-date resource will allow the reader to harness the potential of X-ray diffraction instruments.…
We report here the use of sulfonated fullerene derivatives and dendrimers with multiple −(O)SO 3 H groups as protonic acid dopants for polyaniline emeraldine base (PANI-EB). While doping of PANI-EB films with the sulfonated dendrimers gives conductivities up to ca. 10 S/cm, the hydrogensulfated fullerenol-doped materi…
Polymers with amidine groups NHCRN in the main chain were prepared by acid catalysed melt polycondensation of 4,4′-diaminodiphenyl methane (DAPM) with various orthoesters. The resulting polyamidines were characterized by 1H-, 13C- and 15N-NMR spectroscopy, differential scanning calorimetry (DSC), thermogravimetry…