Materials Literature
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An atomistic pseudopotential method is used to investigate the electronic and optical properties of spherical InAs nanocrystals. Our calculated interband (valence-to-conduction) absorption spectra reproduce the features observed experimentally both qualitatively and quantitatively. The results relative to intraband (v…
A study of the relationships between the stress-induced phase transitions and the mechanical properties of isotactic propylene-hexene copolymers with hexene concentration in the range 1−26 mol%, prepared with metallocene catalysts, is reported. Hexene units are included in crystals of α form of isotactic polypropylene…
A Pennsylvania anthracite was heat-treated to temperatures in excess of 2000 °C. Carbides formed at ∼2200 °C and then decomposed at ∼2500 °C. This process aided in the graphitization of the anthracite. The carbide formation−decomposition reactions were the sole graphitization mechanism for this anthracite. This was sh…
We present the first examples of thermotropic biaxial mesophases in mixtures of model attractive uniaxial molecules. Nematic and smectic biaxial phases are identified. The nematic biaxial phase has remained a key challenge in the science of liquid crystals since it was first proposed almost 40 years ago. Very recently…
A ZnO-based smart surface functionalized by a surface-confined sub-monolayer layer of a purpose-built redox molecule is realized. The hybrid ferrocene/ZnO assembly exhibits a controllable wetting behavior with a contact angle that can be rapidly and reversibly adjusted to a defined value ranging from 110 ° to less tha…
Hexagonal β-NaYF 4 was synthesized as capped bipyramidal microdisks solvothermally from yttria (Y 2 O 3 ), sodium fluoride and ammonium hydrogen fluoride. The microdisks are bound by up to eighteen faces; six {202̅3} facets on both the top and bottom of the disk and six radial {101̅0} facets around its central band. T…
Multifunctional silica nanocapsules containing magnetic nanoparticles and fluorescent quantum dots with a single surface hole fabricated by a single-step emulsion-mediated process are described. The silica nanocapsules (see images) are easily internalized by phagocytic dendritic cells and show a high potential as bimo…
Rod-shaped ZnO particles were grown over wood cellulose fibers using a two-step process. In the first step, the formation of ZnO seeds at cellulose fibers surfaces was induced by the alkaline hydrolysis of aqueous Zn(II); in the second step, the growth of the ZnO seeds into larger nanoparticles was promoted by the con…
We studied the confinement effect on the interaction force in nematic liquid crystal colloids with spherical particles inducing planar anchoring. Using magneto-optical tweezers, we measured the spatial dependence of the quadrupolar structural interparticle force over 4 orders of magnitude. For small separations, the i…
Using ab initio density functional theory methods, the optimized structure of the single-, double-, and triple-layered graphene nanoribbons with different stacking orders and edges is calculated along with their Raman spectrums. For each case studied, graphene is found to be a potential source of vibrational signals i…
A solid catalyst for enantioselective cyanosilylation of aldehydes was prepared by encapsulating a chiral vanadyl Salen complex [VO(Salen)] in the nanocage of SBA-16. After encapsulation, the pore entrance size of SBA-16 was finely tuned through a silylation method to confine the metal complex in the nanocage and allo…
EuFe 2 As 2 is a member of the ternary iron arsenide family. Similar to BaFe 2 As 2 and SrFe 2 As 2 , EuFe 2 As 2 exhibits a clear anomaly in resistivity near 200 K. Here, we report the discovery of superconductivity in Eu 0.7 Na 0.3 Fe 2 As 2 by partial substitution of the europium site with sodium. ThCr 2 Si 2 tetra…
The outermost member of the 112 family LaBaCo 2 O 5.5 has been synthesized using a multistep method to stabilize its structure. Its structural study, combining neutron powder diffraction and electron microscopy, shows that its orthorhombic matrix consists of layers of corner-shared CoO 6 octahedra interconnected throu…
n-Type doping of CdSe nanowires is achieved by either co-evaporating indium at different temperatures during growth, or post-growth doping via a thermal diffusion process. The conductivity of CdSe nanowires is tuned reproducibly by nearly five orders of magnitude in a controlled way, and carrier concentration as high…
We report upper critical field ${B}_{c2}(T)$ data for disordered (arsenic-deficient) ${\mathrm{LaO}}_{0.9}{\mathrm{F}}_{0.1}{\mathrm{FeAs}}_{1\ensuremath{-}\ensuremath{\delta}}$ in a wide temperature and magnetic field range up to 47 T. Because of the large linear slope of ${B}_{c2}\ensuremath{\approx}\ensuremath{-}5.…
The self-assembly of molecules in a gel by strong pi-pi stacking interactions between the thienylvinylene anthracene backbones and van der Waals interactions between the long alkyl chains has generated nanofibers; from the organogels, organic single-nanofiber transistors were successfully embodied.
In this paper, the synthesis of a new type of intrinsically chiral, directly beta,beta'-linked, octa-meso-aryl-substituted bisporphyrins is described, by using an optimized Suzuki-Miyaura coupling procedure. This strategy leads to a broad variety of such axially chiral 'superbiaryls', differing in their metalation sta…
A new pregnanone, named calotropone (1), was isolated from the EtOH extract of the roots of Calotropis gigantea L. together with a known cardiac glycoside. The structures were elucidated by a study of their physical and spectral data. Compounds 1 and 2 displayed inhibitory effects towards chronic myelogenous leukemia…
A short Bi doped fiber laser operating in the wavelength region of 1160-1179 nm has been demonstrated. The influence of unsaturable loss on laser performance is investigated. Excited state absorption in Bi doped germano-alumino silicate fiber is reported in the 900-1300 nm wavelength range under 800 and 1047 nm pumpin…
Ligand exchange reactions of Au 25 (SCH 2 CH 2 Ph) 18 with hexanethiol (HSC6) and thiophenol (HSPh) as incoming ligands, and Brust reaction nanoparticle syntheses using mixtures of thiols (HSCH 2 CH 2 Ph and HSC6), produce nanoparticles having different, ideally statistically determined, relative populations of the tw…