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Provides information on a study which created a unique type of two dimensional (2D) isotropic media with crystalline texture in the magnetic layer. Intrinsic signal-to-noise ratio, cross track noise and texture-induced modulation noise; Thin-film media demanded by increasing linear and track density; Comparison of 2D-isotropic media with oriented and three dimensional random isotropic media.

The antigenic determinant recognized by the monoclonal antibody that had been raised against synthetic human interferon-α1 (IFN-α1) fragment 111–166 [Arnheiter, H., Thomas, R. M., Leist, T., Fountoulakis, M., and Gutte, B. (1981) Nature (Lond.) 294, 278–280] and that cross-reacted with human IFN-α1, IFN-α2, and IFN-αA made in Escherichia coli, was localized to the region between residues 151 and 166 using synthetic COOH-terminal interferon fragments. In solid-phase radioimmunoassays neither the strongly hydrophilic COOH-terminal nonapeptide IFN 158–166 nor its mixtures with IFN 151–162 or IFN 149–158 showed any measurable interaction with the antigen binding site of the monoclonal antibody. For antibody binding, the full covalent structure of IFN 151–166 was required. Quantitatively very similar results were obtained with IFN 149–166 and IFN 143–166. The synthetic COOH-terminal hexadecapeptide of human IFN-α1 (IFN 151–166) could be crystallized. [ABSTRACT FROM AUTHOR]

Abstract: Tungsten oxide (W-oxide) nanoparticles doped and codoped with different transition-metal (TM) ions (Fe, Pt, Cu and Pd) were synthesized by hydrochloric acid-assisted precipitation. The synthesized powders were characterized by X-ray diffraction (XRD), diffuse reflectance spectroscopy (DRS) and magnetic characterization methods. The room temperature (RT) monoclinic (P21/n) structure founded for pristine WO3 nanopowder was converted into orthorhombic (Pbam) structure by Fe-doping, while codoping, (Fe-Pt) and (Fe-Cu) preserved the P21/n space group (SG) structure. It was found that the hydrogenation of the synthesized doped-samples corroded the crystallites without changing the crystalline SG structure. Moreover, controllable room temperature ferromagnetic (RT-FM) properties were created by hydrogenation of the codoped W-oxide samples. The oxygen vacancies-mediated ferromagnetic (FM) interaction could be responsible for the observed FM. The relative highest RT-FM energy was created with hydrogenated Fe-Pd codoped W-oxide. Therefore, Fe-Pd-codoped W-oxide nanopowder could be considered as a potential candidate for many applications involving partial FM properties, such as catalysts and optical phosphors.Graphical Abstract: [ABSTRACT FROM AUTHOR]

The article discusses a study where a straightforward synthetic route to synthesize specific MnOx/G nanocomposites by controlling gas environment was developed. Topics discussed include the preparation of graphite oxide (GO) by exfoliation and oxidation of graphite powder according to the modified Hummers and Offeman's method and indication of the formation of crystalline MnO, Mn3O4 and MnO2 nanoparticles on graphene.

The origins of spin exchange in crystalline thin films of Copper Octabutoxy Phthalocyanine (Cu-OBPc) are investigated using Magnetic Circular Dichroism (MCD) spectroscopy. These studies are made possible by a solution deposition technique which produces highly ordered films with macroscopic grain sizes suitable for optical studies. For temperatures lower than 2 K, the contribution of a specific state in the valence band manifold originating from the hybridized lone pair in nitrogen orbitals of the Phthalocyanine ring, bears the Brillouin-like signature of an exchange interaction with the localized d-shell Cu spins. A comprehensive MCD spectral analysis coupled with a molecular field model of a σπ − d exchange analogous to sp-d interactions in Diluted Magnetic Semiconductors (DMS) renders an enhanced Zeeman splitting and a modified g-factor of −4 for the electrons that mediate the interaction. These studies define an experimental tool for identifying electronic states involved in spin-dependent exchange interactions in organic materials. [ABSTRACT FROM AUTHOR]

2 inch-diameter GaN films with homogeneous thickness distribution have been grown on AlN/Si(111) hetero-structures by pulsed laser deposition (PLD) with laser rastering technique. The surface morphology, crystalline quality, and interfacial property of as-grown GaN films are characterized in detail. By optimizing the laser rastering program, the ~300 nm-thick GaN films grown at 750 °C show a root-mean-square (RMS) thickness inhomogeneity of 3.0%, very smooth surface with a RMS surface roughness of 3.0 nm, full-width at half-maximums (FWHMs) for GaN(0002) and GaN(102) X-ray rocking curves of 0.7° and 0.8°, respectively, and sharp and abrupt AlN/GaN hetero-interfaces. With the increase in the growth temperature from 550 to 850 °C, the surface morphology, crystalline quality, and interfacial property of as-grown ~300 nm-thick GaN films are gradually improved at first and then decreased. Based on the characterizations, the corresponding growth mechanisms of GaN films grown on AlN/Si hetero-structures by PLD with various growth temperatures are hence proposed. This work would be beneficial to understanding the further insight of the GaN films grown on Si(111) substrates by PLD for the application of GaN-based devices. [ABSTRACT FROM AUTHOR]

Examines the structure of the Möbius strip in crystalline ribbons formed by the crystals of niobium and selenium. Mechanisms for the ring formation; Difficulty of the growth of the Möbius strip; Description of the phase transition in different topological arrangements of NbSe[sub 3].

Using first-principles calculations, we investigate the band structure evolution and topological phase transitions in TlBiS2 and TlSbS2 under hydrostatic pressure as well as uniaxial and biaxial strain. The phase transitions are identified by parity analysis and by calculating the surface states. Zero, one, and four Dirac cones are found for the (111) surfaces of both TlBiS2 and TlSbS2 when the pressure grows, which confirms trivial-nontrivial-trivial phase transitions. The Dirac cones at the points are anisotropic with large out-of-plane component. TlBiS2 shows normal, topological, and topological crystalline insulator phases under hydrostatic pressure, thus being the first compound to exhibit a phase transition from a topological to a topological crystalline insulator. [ABSTRACT FROM AUTHOR]

We study spin and valley transports in junctions composed of silicene and topological crystalline insulators. We consider normal/magnetic/normal Dirac metal junctions where a gate electrode is attached to the magnetic region. In a normal/antiferromagnetic/normal silicene junction, we show that the current through this junction is valley and spin polarized due to the coupling between valley and spin degrees of freedom, and the valley and spin polarizations can be tuned by local application of a gate voltage. In particular, we find a fully valley and spin polarized current by applying the electric field. In a normal/ferromagnetic/normal topological crystalline insulator junction with a strain induced in the ferromagnetic segment, we investigate valley-resolved conductances and clarify how the valley polarization stemming from the strain and exchange field appears in this junction. It is found that by changing the direction of the magnetization and the potential in the ferromagnetic region, one can control the dominant valley contribution out of four valley degrees of freedom. We also review spin transport in normal/ferromagnetic/normal graphene junctions, and spin and valley transports in normal/ferromagnetic/normal silicene junctions for comparison. [ABSTRACT FROM AUTHOR]

The article presents the study of the optimization of sodium acetate to understand the reactions of triazinone. It states that a light spot started to appear on the thin layer chromatography during reaction monitoring. It cites that the reaction mixture has produce white colored crystals during cooling. It also mentions that a fourier transform infrared (FT-IR) spectrum appeared on the presence of two sharp stretching above 3,000 centimeter (CM).

The article focuses on the effects of adding and reducing atoms in copper-niobium multilayer nanocomposites forming two flaw-free interfaces between copper (Cu) and niobium (Nb). Study shows that radiation striking crystalline materials may damage their structure and other properties through the generation of vacancies or interstitials. It reveals that the first interface exists from the combination of the face-centered cubic Cu (111) plane and body-centered cubic Nb (110) plane. Other interface needs a straining and rotating of the Cu (111) to make it a 0.5% less dense in the interfacial area.

Interfacing semiconducting nanostructures with conducting or insulating substrates to attain a three-dimensional (3D) integrated platform is highly desirable for advanced nanoscale electronics and optoelectronics applications. Taking ZnO as an example, the article shows that high crystallinity one-dimensional and two-dimensional nanostructures can be epitaxially and vertically grown into 3D architectures on both conducting and insulating single crystalline substrates. These are achieved by specifically controlling either the spacing between the catalyst spots or the thickness of the catalyst thin film. Vertical growth of the ZnO nanostructures are observed as a result of the good epitaxial lattice match of the c plane of ZnO with the hexagonal basal plane of HOPG and plane of sapphire.