Materials Literature
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A simple, novel method to produce porous 2,3-dialdehydecellulose (DAC) membranes as a potential tissue-engineering scaffold has been developed from methylolcellulose by the simultaneous water-induced phase separation and sodium chloride salt leaching techniques, followed by oxidation with sodium periodate in water. Me…
Electric and magnetic properties were investigated on p-type Zn1−xCrxTe doped with nitrogen (N) as an acceptor. Thin films of p-Zn1−xCrxTe(x≦0.09) were grown by molecular-beam epitaxy with the supply of N2 gas excited by rf plasma. With the increase of Cr composition x at an almost fixed N concentration of the order o…
A strong generic coupling between self-localized solitons and conformations of a pi-conjugated polymer chain is demonstrated through ab initio calculations and the underlying mechanisms revealed by using an extended Hubbard model. We show that significant chain bending and twisting of trans- and cis-polyacetylene resu…
Variable temperature transport between 1.4 and 300 K, structural imaging, and theoretical calculations were used to characterize the properties of electrically active 24 degrees and 36.8 degrees [001] tilt SrTiO3 grain boundaries with 0.1 at. % niobium doping. An anomaly in boundary resistance and capacitance characte…
Abstract A versatile coupling reaction for the preparation of polybutadiene–poly‐(hexafluoropropylene oxide) (BF) diblock copolymers is described. Six diblock copolymers with different block lengths were characterized by nuclear magnetic resonance spectroscopy and size exclusion chromatography; all six had total molec…
Abstract Summary: The synthesis of new N ‐cyclopentyl‐ exo , endo ‐norbornene‐5,6‐dicarboximide (CpNDI) ( 3a ) and N ‐cyclohexyl‐ exo , endo ‐norbornene‐5,6‐dicarboximide (ChNDI) ( 3b ) monomers was carried out. From these monomers, two polynorbornene dicarboximides with cyclopentyl and cyclohexyl pendant groups, poly…
The biological safety of degradation products from degradable biomaterials is very important. In this study a new method is proposed to test the cytotoxicity of these degradation products with the aim to save time, laboratory animals, and research funds. A biodegradable polyurethane (PU) foam was subjected to this tes…
Tetra(pentafluorophenyl)porphyrin (H 2 TPFPP) has been cocrystallized with C 60 from arene solvents to give H 2 TPFPP·C 60, 1, H 2 TPFPP·C 60 ·8Benzene, 3, and 3H 2 TPFPP·2C 60 ·6Toluene, 4 . Their X-ray structures have been determined to identify the supramolecular interactions that lead to tape, sheet, and prismatic…
Proton nuclear magnetic relaxation dispersion (NMRD) profiles were recorded between 0.24 mT and 1.4 T for lanthanum(III)- and gadolinium(III)-containing [15]metallacrown-5 complexes derived from alpha-aminohydroxamic acids and with copper(II) as the ring metal. The influence of the different R-groups on the proton rel…
Analytical expressions for the optical matrix elements of semiconducting carbon nanotubes are obtained for different polarizations of the incident light. It is shown that, for the light polarized along the nanotube axis and transitions between the extrema of electronic subbands, the optical matrix element only weakly…
The reaction between Ln(NO3)3*xH2O, Cs3[W(V)(CN)8]*H2O and 2,2':6',2''-terpyridine (terpy) leads to the original isomorphous cyano-bridged [Ln(III)(terpy)(DMF)4][W(V)(CN)8] *6H2O [Ln = Gd (1), Sm (2)] 1-D chains. The crystal structures of {Ln(III)W(V)} chains and consist of alternating {[W(CN)8]} and {[Ln(terpy)]} bui…
A detailed investigation of the unusual dynamics of the magnetization of ${({\mathrm{Et}}_{4}\mathrm{N})}_{3}{\mathrm{Fe}}_{2}{\mathrm{F}}_{9}$ $({\mathrm{Fe}}_{2})$, containing isolated ${[{\mathrm{Fe}}_{2}{\mathrm{F}}_{9}]}^{3\ensuremath{-}}$ dimers, is presented and discussed. ${\mathrm{Fe}}_{2}$ possesses an $S=5$…
We peel off cationic and anionic polyelectrolytes from different substrates (cationic, hydrophobic and metallic) with the atomic force microscope (AFM). By varying the salt concentration, the measured plateau forces can be separated into electrostatic and non-electrostatic contributions to the adsorption energy. Surpr…
Abstract This paper describes the synthesis of photoisomerizable derivatives of isosorbide. These derivatives contain a stilbene or cinnamate moiety and can therefore be used as photoisomerizable chiral compounds in cholesteric liquid‐crystalline mixtures. The reflection wavelength of cholesteric layers made from thes…
We report in situ density values of amorphous ice obtained between 0.3 and 1.9 GPa and 144 to 183 K. Starting from high-density amorphous ice made by pressure-amorphizing hexagonal ice at 77 K, samples were heated at a constant pressure until crystallization to high-pressure ices occurred. Densities of amorphous ice w…
It is well known that a silica surface cannot adsorb duplex DNA in common aqueous solution (not chaotropic solution) because of the electrostatic repulsion of the silica surface and polyanionic DNA. However, we recently found that when duplex DNA in phosphoric acid form (or in acidic solution) was used, DNA was succes…
Abstract The crystalline structure of polyamide‐12 (PA12) was studied by solid‐state 13 C nuclear magnetic resonance (NMR) as well as by synchrotron wide‐ and small‐angle X‐ray scattering (WAXS and SAXS). Isotropic and oriented PA12 showed different NMR spectra ascribed to γ‐ and γ′‐crystalline modifications, respecti…
We derive multipole-based integral estimates (MBIE) as rigorous and tight upper bounds to four-center two-electron integrals in order to account for the 1/R distance decay between the charge distributions, which is missing in the Schwarz screening commonly used in ab initio methods. Our screening criteria are valid fo…
Self-assembled bilayer membranes have a remarkable inclination to form closed shells or vesicles. This bilayer-vesicle transition has been shown experimentally and by various kinds of computer simulation techniques. Here we study this transition using coarse-grained molecular dynamics. The advantage of this simulation…
Inspired by recent claims that compounds composed of V-shaped molecules can exhibit the elusive biaxial nematic phase, we have developed a generic simulation model for such systems. This contains the features of the molecule that are essential to its liquid crystal behavior, namely the anisotropies of the two arms and…