Materials Literature
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Molecular dynamics simulations have been performed to investigate the reaction behaviour of species that may affect the growth of ultrananocrystalline and nanocrystalline diamond films. We calculated the sticking coefficients of CH x ( x = 0–4), C 2 H x ( x = 0–6), C 3 H x ( x = 0–2) and C 4 H x ( x = 0–2) on diamond…
The marine bacterium Saccharophagus degradans was investigated for the synthesis of polyhydroxyalkanoates (PHAs), using glucose as the sole source of carbon in a two-step batch culture. In the first step the microorganism grew under nutrient balanced conditions; in the second step the cells were cultivated under limit…
We report on anionic ring-opening polymerization (ROP) of racemic beta-(methoxymethyl)-beta-propiolactone (MOMPL) and beta-(ethoxymethyl)-beta-propiolactone (EOMPL) initiated by supramolecular complex of potassium acetate and tetrabutylammonium acetate (Bu4N+ Ac) as well as by tetrabutylammonium hydroxide, respectivel…
The clustering of nanoparticles (NPs) in solutions and polymer melts depends sensitively on the strength and directionality of the NP interactions involved, as well as the molecular geometry and interactions of the dispersing fluids. Since clustering can strongly influence the properties of polymer-NP materials, we ai…
Carbon nanotubes are nanostructures that promise much in the area of constructing nanoscale devices due to their enhanced mechanical, electrical and thermal properties. In this paper, we examine a gigahertz oscillator that comprises a carbon nanotube oscillating in a uniform concentric ring or bundle of carbon nanotub…
A main-chain-type organoboron quinolate polymer was prepared by means of polymer reaction between the precursor polymer and triphenylborane. The precursor polymer was synthesized by the Sonogashira−Hagihara coupling reaction between diyne monomer and tert -butoxycarbonyl- (Boc-) protected dibromoquinolinol monomer. Th…
Phase-contrast transmission electron microscopy (PC-TEM) and quick freezing method have been combined to study the initial growing process of a self-assembled lipid nanotube in water. The PC-TEM enabled us to detect thin lamellar edge structure and the very fast growth of the newborn edge to a thin tube with high cont…
Using first-principles density functional theory based on gradient corrected approach, we have studied interaction of ${\mathrm{H}}_{2}$ molecule with Li-doped carbon nanotube and nanotube based peapod structures. We find that ${\mathrm{H}}_{2}$ physisorbs on pure carbon nanotube, which is in agreement with earlier st…
We have synthesized linear poly(lactic acid) (BHMBA−PLA) possessing a pendent carboxylic acid group via ring-opening polymerization (ROP) of l - or d, l -lactide using bis(hydroxymethyl) butyric acid (BHMBA) as initiator and stannous octoate as catalyst. Polymerizations were typically conducted in the bulk for ∼3 h at…
We present the results of experiments on the optical, electrical and magnetic properties and electronic structure and optical spectrum calculations of the Heusler alloys Fe 2 TiAl, Fe 2 VAl and Fe 2 CrAl. We find that the drastic transformation of the band spectrum, especially near the Fermi level, when replacing the…
In this paper, thermal treatment of Zn(NH 3 ) 4 2+ precursor in ethanol solvent leading to the formation of the ZnO hollow spheres is reported. It was demonstrated that the pH value of the initial mixture and the volume ratio of the ethanol with the solution plays the key function in the formation of hollow spheres. T…
By means of the ab initio all-electron new full-potential linear-muffin-tin orbitals method, calculations were made for elastic constants C 11 , C 12 and C 44 for Si, ZrO 2 and HfO 2 in their cubic phase, and constants C 11 , C 22 , C 33 , C 12 , C 13 , C 23 , C 44 , C 55 and C 66 for HfO 2 in its orthorhombic phase.…
Mg2B2O5 nanowires with (010) twins were synthesized for the first time using a catalyst-free method. The microstructure of the Mg2B2O5 nanowires has been extensively studied by cross-sectional high-resolution transmission electron microscopy. Nanoindentation tests were performed directly on individual nanowires to pro…
More than a pretty phase: A class of helical β-peptides has been discovered that form lyotropic liquid-crystalline (LC) phases in water. The β-peptide sequence strongly affects the mode of assembly and ultimately whether a LC phase is formed. For a non-globally amphiphilic β-peptide that can form a LC phase, cryo-TEM…
Shapeshifters: The shape and size of gold nanocrystals were controlled simultaneously through directed surface overgrowth from polyhedral and spherical seeds of different sizes. The resulting cubes, cuboctahedra, and octahedra (shown as SEM images for growth from spherical seeds of two sizes) exhibited characteristic…
Based on first-principles calculations, we have investigated electronic structures and magnetic properties of SnO 2 doped with V, Mn, Fe, and Co. Our results show that ferromagnetism is the ground state and that the Curie temperatures are expected to have high values for Fe- and Co-doped SnO 2 , which is in good agree…
We report the magnetoresistance (MR) properties of quasi-two-dimensional mesoscopic graphite (MG) spin valve devices consisting of MG flakes contacted by ferromagnetic (FM) electrodes. For devices in which an ultrathin magnesium oxide $(\mathrm{MgO})$ tunnel barrier is inserted at the FM/MG interface, the spin valve e…
We studied the temperature and excitation intensity dependence of exciton luminescence in individual single-walled carbon nanotubes (SWNTs) using single nanotube photoluminescence (PL) spectroscopy. The linear temperature dependence of the PL linewidth in a single SWNT implies that the exciton dephasing is dominated b…
Asymmetric nanocomposite particle pairs of polystyrene and silica were prepared via one-step miniemulsion polymerization for the first time. The transmission electron microscopy images showed that these nanocomposite particle pairs were monodisperse and highly asymmetric in morphology. The key to obtaining the asymmet…
The coupling between $z$ valleys in the conduction band of a Si quantum well arises from phenomena occurring within several atoms from the interface, thus ruling out a theoretical description based on pure effective mass theory. However, the complexity and size of a realistic device precludes an analytical atomistic d…