Materials Literature
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The crystal and molecular structures of two novel derivatives of the lophine chromophore with different solvents of crystallization are presented and discussed. Phenol, 2-[4,5-bis(4-methoxyphenyl)-1 H -imidazole-2-yl]-4-nitro ( 1 ) and phenol, 2-[4,5-bis(4-methyl-phenyl)-1 H -imidazole-2-yl]-4-nitro ( 2 ) form inclusi…
Pseudomonas sp. 14-3 accumulates polyhydroxybutyrate (PHB) from octanoate, but not from glucose. To elucidate this unusual phenotype, genes responsible for the synthesis of PHB were cloned and analyzed. A PHB polymerase gene (phaC) was found downstream from genes coding for a beta-ketothiolase (phaA), an acetoacetyl-c…
Electrochemical studies of thiol-capped ZnSe nanocrystals in aqueous solution have demonstrated several distinct oxidation and reduction peaks in the voltammograms, with the peak positions being dependent on the size of the nanocrystals and their photoluminescence quantum efficiency. The evolution of the specific feat…
The EPR spectra of radical surfactant probes embedded in cetyltrimethylammonium bromide (CTAB) and trimethylbenzene (TMB) stable water emulsions (TMB/CTAB = 13) were analyzed to provide information on the kinetics of formation of micelle-templated silicoaluminas (MTSA) at 343 K, obtained by means of silica and alumina…
Amoxicillin is an important semi-synthetic antibiotic produced in large quantities around the world, and developing a highly cost-effective crystallization process for amoxicillin is of significant importance. In this study an in situ turbidity meter is used to measure the induction period for the onset of nucleation…
We report on the preparation of supported columnar CeO(2) nanostructures by a simple catalyst-free chemical vapor deposition process at temperatures as low as 623 K. A suitable choice of experimental parameters enables us to control the structural and morphological features of the resulting ceria nanosystems.
Abstract Experimental observations (ellipsometry, scanning force microscopy, and nuclear magnetic recsonance (NMR)) of the freezing behavior of thin supported films as well as the free surface of atactic polystyrene are reported, taken at a particularly small molecular weight of 2 kg/mol. Remarkably, we find the same…
Indium tin oxide (ITO) catalysts with different In/Sn ratios have been prepared by the co-precipitation method. The catalysts were evaluated for methane combustion at different temperatures (673-873 K) with a space velocity of 30 000 h(-1). The results showed that methane could be completely oxidized at 873 K with ITO…
We report that the properties of the isotropic to nematic liquid crystalline phase transition of F-actin depend critically on the average filament length. For average filament lengths longer than 2 microm, we confirm previous findings that the phase transition is continuous in both alignment and concentration. For ave…
Static and time-resolved optical measurements are reported for three cyclic hexameric porphyrin arrays and their self-assembled complexes with guest chromophores. The hexameric hosts contain zinc porphyrins and 0, 1, or 2 free base (Fb) porphyrins (denoted Zn(6), Zn(5)Fb, or Zn(4)Fb(2), respectively). The guest is a c…
This investigation describes the formation of a metal nanorattle with a pure metal shell by varying experimental parameters. The galvanic replacement reaction between silver and chloroauric acid was adopted to prepare hollow metal nanoparticles. This approach is extended to produce nanorattles of Au cores and Au shell…
Silk fibroin of the silkworm Bombyx mori has been studied extensively, while the research on Antheraea pernyi silk fibroin (A. pernyi SF) in biomaterials is only at an early stage. In this study, the attachment, morphology, growth and phenotype of human bone marrow derived mesenchymal stem cells (hBMSCs) cultured on t…
Shear innovation: By analyzing the crystallographic shear (CS) structures of “Pb2Fe2O5” (see picture; spheres Pb, polyhedra FeO6/FeO5), new building principles are derived for perovskite-based compounds containing cations with a lone electron pair in the A sites of the perovskite structure. The chemical composition ca…
Using ab initio calculations, we show that the encapsulation of Y, La, and Ac metal $(M)$ atom stabilizes the dodecahedral fullerene anion $M@\mathrm{Si}_{20}{}^{\ensuremath{-}}$ in the icosahedral symmetry. Similar to ${\mathrm{C}}_{60}$, it is the ideal cage of silicon and the largest that can be stabilized by an $M…
Abstract Novel polyurethanes (PUs) based on 2,2′‐[ethane‐1,2‐diylbis(nitrilomethylylidene)]diphenol and 2,2′‐[hexane‐1,6‐diylbis(nitrilomethylylidene)]diphenol as hard segments containing four aromatic diisocyanates (4,4′‐diphenylmethane diisocyanate, toluene 2,4‐diisocyanate, isophorone diisocyanate, and hexamethylen…
The synthesis of an inverted, methoxylated sapphyrin derivative is described. This system, wherein inversion of pyrrolic nitrogen atoms is configurationally enforced via the use of a 3,3'-bipyrrolic precursor, displays what is best described as "weak aromaticity" as judged from its spectroscopic features and supportin…
The magnetite (Fe(3)O(4)) nanoparticles were prepared by coprecipitation of Fe(3+) and Fe(2+) with an aqueous NaOH solution. The Fe(3)O(4)/polyaniline (PANI) magnetic composite nanoparticles with a core-shell structure with a diameter of 30-50 nm were prepared via an in situ polymerization of aniline in an aqueous sol…
We investigated the electronic structures of the two-dimensional layered perovskite ${\mathrm{Sr}}_{2}M{\mathrm{O}}_{4}$ ($M=4d$ Ru, $4d$ Rh, and $5d$ Ir) using optical spectroscopy and polarization-dependent O $1s$ x-ray absorption spectroscopy. While the ground states of the series of compounds are rather different,…
A very good host: The guest acid molecules of hydrothermally synthesized [V(O)(bdc)](H2bdc)0.71 (bdc=benzenedicarboxylate) are removed to give high-quality single crystals of [V(O)(bdc)] (1). On absorption of guest molecules from the liquid phase, 1 undergoes crystal-to-crystal transformations (aniline: 2; thiophene:…
We have prepared three isomeric donor-acceptor systems, in which two phthalocyanine (Pc) units have been attached to the 1-,5- (1a), 1-,8- (1b), or 2-,6- (1c) positions of a central anthraquinone (AQ) moiety, leading to packed (1b) or extended (1a and 1c) topologies. The electronic interactions between the donor and t…