Materials Literature
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We investigate the structure and thermal behaviour of boron nitride (BN) nanotubes using molecular-dynamics simulations based on the Tersoff-like potential. The strain energy decreases with increasing diameter, which is proportional to the inverse square of the tube diameter on the basis of continuum elastic theory. T…
We describe the syntheses, the 1H NMR studies in CD3OD and D2O as solvent, the X-ray characterization, and the luminescence properties in D2O solution of the two complexes Eu.1 and Er.1, where 1 is a dipartite ligand that includes (i) a 1,4,7,10-tetraazacyclododecane-1,4,7-triacetic acid (DO3A) unit serving as hosting…
Anisotropic particles suspended in a nematic liquid crystal disturb the alignment of the liquid crystal molecules and experience small forces that depend on the particles' orientation. We have measured these forces using magnetic nanowires. The torque on a wire and its orientation-dependent repulsion from a flat surfa…
The magnetic properties of ${\mathrm{Co}}^{2+}$ ions in epitaxial (Zn,Co)O layers with 10% Co concentration have been studied by electron paramagnetic resonance spectroscopy. The Co-related EPR spectrum is characterized by a 200-G broad anisotropic single line with g factors close to those of the isolated ${\mathrm{Co…
Two composite compounds, [{Ce(DMF) 4 (H 2 O) 3 }{Ce(DMF) 4 (H 2 O) 4 }(P 2 W 18 O 62 )]·H 2 O ( 1 ) (DMF = N, N -dimethylformamide) and [{La(DMF) 6 (H 2 O)}{La(DMF) 4.5 (H 2 O) 2.5 }·(P 2 W 18 O 62 )] ( 2 ), have been constructed at room temperature and characterized by single crystal X-ray structural analyses, ESR sp…
Starburst triarylamines 2 and 3 were electropolymerized to form electrochromic thin films. Film from 2 showed intense absorption at 372 nm before voltage was applied. There were two absorption bands at 496 nm and 1000−2000 nm at 0.3 V, and a broad band, which peaked at 807 nm at 0.6 V. Film from 3 showed intense absor…
We tested whether internal transcribed spacer (ITS) rDNA sequence differences are correlated with sexual compatibility in the Sellaphora pupula complex, a model system for investigations of the species concept and speciation in diatoms. The phylogenetic relationships among the demes and the systematic position of the…
We have measured carbon nanotube quantum dots with multiple electrostatic gates and used the resulting enhanced control to investigate a nanotube double quantum dot. Transport measurements reveal honeycomb charge stability diagrams as a function of two nearly independent gate voltages. The device can be tuned from wea…
Transport properties of magnetic multilayers in current perpendicular to the plane of the layers geometry are defined by diffusive scattering in the bulk of the layers, and diffusive and ballistic scattering across the interfaces. Due to the short screening length in metals, layer by layer treatment of the multilayers…
Electronic properties of proposed new families of carbon single walled nanotubes are investigated. These nanotubes, called graphynes, result from the elongation of covalent interconnections of graphite-based nanotubes by the introduction of yne groups. Analogous to ordinary nanotubes, armchair, zigzag and chiral graph…
The results of dc magnetization, heat capacity, electrical resistivity (rho) and magnetoresistance measurements are reported in detail for the compounds, RCuAs2 for R= Pr, Nd, Sm, Gd, Tb, Dy, Ho, and Er, crystallizing in HfCuSi2-type tetragonal structure, with the aim of bringing out anomalies among 'normal' (that is,…
We show that a simple first-principles correction based on the difference between the singlet-triplet CO excitation energy values obtained by DFT and high-level quantum chemistry methods yields accurate CO adsorption properties on a variety of metal surfaces. We demonstrate a linear relationship between the CO adsorpt…
We use an atomic force microscope (AFM) tip to locally probe the electronic properties of semiconducting carbon nanotube transistors. A gold-coated AFM tip serves as a voltage or current probe in three-probe measurement setup. Using the tip as a movable current probe, we investigate the scaling of the device propertie…
Population genetic structure was determined for the planktonic diatom Ditylum brightwellii (West) Grunow in two connected estuaries—Puget Sound and the Strait of Juan de Fuca (WA, USA). Three genetically distinct populations were detected that were characterized by different microsatellite allele distributions and uni…
The synthesis of layered ferrite-lead titanate zirconate (PZT) and lanthanum nanganite-PZT and the observation of giant magneto-electric interactions are discussed. The ferrites used in our studies included pure and Zn substituted cobalt-, nickel- and lithium ferrites. Ferromagnetic manganites used included both calci…
The physics of manganites appears to be dominated by phase competition among ferromagnetic metallic and charge-ordered antiferromagnetic insulating states. Previous investigations (Burgy {\it et al.}, Phys. Rev. Lett. {\bf 87}, 277202 (2001)) have shown that quenched disorder is important to smear the first-order tran…
The photoluminescence center ${D}_{\mathrm{II}}$ is a persistent intrinsic defect which is common in all SiC polytypes. Its fingerprints are the characteristic phonon replicas in luminescence spectra. We perform ab initio calculations of vibrational spectra for various defect complexes and find that carbon antisite cl…
Efficient determination of protein crystal structures requires automated x-ray data analysis. Here, we describe the expert system ELVES and its use to determine automatically the structure of a 12-kDa protein. Multiwavelength anomalous diffraction analysis of a selenomethionyl derivative was used to image the Asn-16-A…
Nylon-6−organoclay nanocomposites were prepared by melt processing via twin-screw extrusion for the purpose of comparing the effect of the number alkyl groups attached to the nitrogen of the organic modifier on the level of organoclay exfoliation. Wide-angle X-ray scattering and transmission electron microscopy techni…
Thin films of tungsten-doped vanadium(IV) oxide were prepared on glass substrates from the atmospheric pressure chemical vapor deposition of vanadium(IV) chloride, tungsten(VI) ethoxide, and water at 500−600 °C. The films were characterized by Raman microscopy, glancing angle X-ray diffraction (GAXRD), X-ray photoelec…