Materials Literature
按标题、摘要、年份、主题和来源检索公开元数据。结果保留作者、摘要、分类与原始来源链接。
We have functionalized single walled carbon nanotubes (SWNTs) with atomic hydrogen generated in a cold plasma. A band at 2924 cm -1 (3.4 μm), characteristic of the C−H stretching mode, is observed using Fourier transform infrared spectroscopy. Additional confirmation of functionalization is provided by irradiating wit…
A series of YBa_{2-x}Sr_xCu_4O_8 single crystals was measured to study the influence of site disorder on the transition line Hss(T) between quasi-ordered vortex lattice and highly disordered vortex glass, as well as on the maximum critical current density within the glass phase, jcmax. When 32% of Ba is replaced by Sr…
Valence electron-energy loss spectroscopy (VEELS) in a dedicated scanning transmission electron microscope, vacuum ultraviolet spectroscopy and spectroscopic ellipsometry, and ab initio band structure calculations in the local density approximation have been used to determine the optical properties and the electronic…
Crystals of the title compound, (NH4)4[H6NiMo6O24]·4H2O containing the well known B-type Anderson–Evans heteropolyoxometalate, were obtained by recrystallization of powder (NH4)4[H6NiMo6O24]·nH2O. The anion has the Ni atom at an inversion center and has close to \overline 3m symmetry, with Ni—O bond lengths in the ra…
We present a detailed theoretical study, based on density-functional calculations, of Na adsorption on ${\mathrm{TiO}}_{2}(110)$ for coverage equal to 1/8, 1/4, and 1/2 monolayers. Two competing threefold adsorption sites are found. In the framework of the Bader theory, we analyze the electron distribution, the interf…
The tricalcium dimanganese heptaoxide (Ca3Mn2O7) member of the Ruddlesden-Popper series Ca(n+1)Mn(n)O(3n+1), i.e. with n = 2, was previously reported with an I-centred tetragonal lattice [a(t) = 3.68 and c(t) = 19.57 A] by Fawcett, Sunstrom, Greenblatt, Croft & Ramanujachary [Chem. Mater. (1998), 10, 3643-3651]. It is…
BACKGROUND: Tryptophan synthase consists of two subunits, alpha and beta. Two distinct subgroups of beta chain exist. The major group (TrpEb_1) includes the well-studied beta chain of Salmonella typhimurium. The minor group of beta chain (TrpEb_2) is most frequently found in the Archaea. Most of the amino-acid residue…
This work is a contribution to better knowledge of the influence of the structure of films on their functional properties obtained from emulsions based on arabinoxylans, hydrogenated palm kernel oil (HPKO), and emulsifiers. The sucroesters (emulsifiers) have a great effect on the stabilization of the emulsified film s…
The application of ultrasound for the treatment of polychlorinated biphenyl (PCB) contaminated sediments was explored in this study with a model system of 4-chlorobiphenyl (4-CB) and synthetic sediments. In the presence of an ultrasonic probe, operating at 20 kHz with a power density of 460 W L(-1), more than 90% of 4…
Syndiotactic polystyrene (sPS) glassy sample crystallizes into the polymer−solvent complex of δ form with T 2 G 2 helical conformation when it is exposed to the atmosphere of organic solvent. This solvent-induced crystallization is observed at room temperature, much lower than the glass transition temperature of sPS.…
Succinyl-CoA synthetase catalyzes the reversible reaction succinyl-CoA + NDP + P(i) <--> succinate + CoA + NTP (N denoting adenosine or guanosine). The enzyme consists of two different subunits, designated alpha and beta. During the reaction, a histidine residue of the alpha-subunit is transiently phosphorylated. This…
The hydration behavior of synthetic magadiite exchanged with H +, Na +, K +, Mg 2+, and Ca 2+ was investigated by combining thermal analyses, water adsorption gravimetry, X-ray diffraction, and spectroscopic techniques, including 29 Si NMR, infrared, and Raman under various pressures. Thermal analyses reveal distinct…
We present in situ x-ray scattering measurements of the surface structures of ${\mathrm{PbTiO}}_{3}$ (001) in equilibrium with PbO vapor. At 875 to 1025 K, a reconstruction having $c(2\ifmmode\times\else\texttimes\fi{}2)$ symmetry is present under most conditions, while a $1\ifmmode\times\else\texttimes\fi{}6$ reconst…
ZnS passivated InP nanoparticles prepared by the TOP/TOPO method have been investigated by photoelectron spectroscopy with tunable synchrotron radiation. Based on the energy dependence of the electron escape depth, we present a method to characterize the core−shell nature of the sample structure. Energy tuning indicat…
The hard sphere disorder-order transition serves as the paradigm for crystallization. However, measurements of the crystallization kinetics for colloidal hard spheres in the coexistence regime are incomplete for early times and are affected by sedimentation. We use time resolved Bragg light scattering to characterize…
The reaction of Sr2CuO3 with air and liquid water was studied to address the origin of the reported variable Curie-Weiss impurity contribution to the magnetic susceptibility X of this compound at low temperatures. Sr2CuO3 was found to decompose upon exposure to either of these environments. The compound Sr2Cu(OH)6 was…
We have studied the magnetic properties of (GaMnAs)m/(GaAs)n superlattices with magnetic GaMnAs layers of thickness between 8 and 16 molecular layers (ML) (23-45 Å), and with nonmagnetic GaAs spacers from 4 ML to 10 ML (11-28 Å). While previous reports state that GaMnAs layers thinner than 50 Åare paramagnetic in the…
Crackling noise is observed in many disordered non-equilibrium systems in response to slowly changing external conditions. Examples range from Barkhausen noise in magnets to acoustic emission in martensites to earthquakes. Using the non-equilibrium random field Ising model, we derive universal scaling predictions for…
We studied the influence of sample preparation and defects in the superconducting properties samples using atomic ratios of Mg:B=1:1 and Mg:B=1:2. Samples were characterized by SEM, and XRD, and the magnetization properties were examined in a SQUID magnetometer. The presence of Mg vacancies was determined by Rietveld…
The effects of structure and morphology on lithium storage in single-wall carbon nanotube (SWNT) bundles were studied by electrochemistry and nuclear magnetic resonance techniques. SWNTs were chemically etched to variable lengths and were intercalated with Li. The reversible Li storage capacity increased from LiC(6) i…