Materials Literature
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The dynamic magnetic properties of the distorted perovskite system ${\mathrm{La}}_{0.7\ensuremath{-}x}{\mathrm{Y}}_{x}{\mathrm{Ca}}_{0.3}{\mathrm{MnO}}_{3}$ $(0<~x<~0.15)$ have been investigated by ac susceptibility and dc magnetization measurements, including relaxation and aging studies. All investigated sampl…
The crystal and magnetic structures of newly synthesized ${\mathrm{Sr}}_{1\ensuremath{-}x}{\mathrm{Ca}}_{x}{\mathrm{MnO}}_{3}$ $(0<~x<~1)$ and ${\mathrm{Sr}}_{1\ensuremath{-}y}{\mathrm{Ba}}_{y}{\mathrm{MnO}}_{3}$ $(y<~0.2)$ perovskite materials (of the $\mathrm{AB}{\mathrm{O}}_{3}$ type) were investigated usi…
The electronic transport properties through junctions connecting nanographite ribbons of different or same width are investigated by means of the Landauer-B\"uttiker approach using a tight binding model. Graphite ribbon with zigzag boundary has a single conducting channel of edge states in the low-energy regime. The e…
BACKGROUND: Molecular imaging of thrombus within fissures of vulnerable atherosclerotic plaques requires sensitive detection of a robust thrombus-specific contrast agent. In this study, we report the development and characterization of a novel ligand-targeted paramagnetic molecular imaging agent with high avidity for…
Abstract The glass‐transition temperatures ( T g ) of some polymers reported in the literature have always been a source of great uncertainty. The values reported for poly(methacrylonitrile) (PMAN, 100 and 120°C) are well above the value determined in this study (67°C). It is clearly shown by FTIR and DSC work that fo…
The electronic structures and spectra have been calculated using the INDO-single- and double-excitation configuration interaction method, and following combination with the sum-over-states method the dynamic third-order polarizabilities in the third-harmonic generation (THG), electric-field-induced second harmonic gen…
A Pb5Ge3O11 metal–ferroelectric–metal–oxide–silicon memory transistor has been fabricated. The device showed a memory window of about 2 V. The memory window was almost saturated at the operation voltage of 2 V. The “off” state drain current (ID) at VD of 0.1 V and VG of 0.5 V is about 1×10−8 A. The “on” state drain cu…
We report on the conductance of multiwalled carbon nanotubes as a function of voltage and temperature between room temperature and 4.2 K. The data show a monotonic decrease in conductance as the temperature is lowered. At temperatures below about 20 K, a nonlinearity develops in the $V(I)$ data, corresponding to a pro…
The electrical resistivity \ensuremath{\rho} and the thermopower \ensuremath{\alpha} of the transition-metal pentatelluride system ${\mathrm{Hf}}_{1\ensuremath{-}X}{\mathrm{Zr}}_{X}{\mathrm{Te}}_{5\ensuremath{-}Y}{\mathrm{Sb}}_{Y}$ have been measured over a broad range of temperature, $10\mathrm{K}<T<300\mathrm{…
Annealing atmosphere effects on domain structures and electrical properties of Pb[(Zn1/3Nb2/3)0.5(Zr0.47Ti0.53)0.5]O3 (PZN–PZT) ferroelectric materials were investigated. The PZN–PZT specimens were annealed in argon, air, oxygen, and PbZrO3 atmospheres after being sintered at 1100 °C in air. The as-sintered specimens…
We have examined the valence-electron emission from Cu, Ge, GaAs, InP, and NiO single crystals under the condition of strong x-ray Bragg reflection; i.e., in the presence of the spatially modulated x-ray standing-wave interference field that is produced by the superposition of the incident and reflected x-ray beams. T…
Abstract The chitosan hydroxyl azacrown ether was synthesized by reaction of hydroxyl azacrown ether with epoxy‐activated chitosan. The C 2 amino group in chitosan was protected from the reaction between benzaldehyde and chitosan to form N ‐benzylidene chitosan. After reaction with epichlorohydrin and azacrown ether,…
The injection of holes from a Ag electrode into poly-dialkoxy-p-phenylene vinylene is investigated by measuring the current–voltage characteristics as a function of temperature. For this model system, the hole injection is hindered by a contact energy barrier of about 1.0 eV. The observed temperature dependence of the…
A low-field theory for paramagnetic relaxation enhancement (PRE), appropriate for the outer-sphere relaxation, is presented for the electron spin quantum number S = 1, 3/2, 2, 5/2, 3 and 7/2. The theory is used to calculate the PRE at low magnetic field, as a function of the translational diffusion coefficient, for va…
Abstract Polyacrylic acid (PAA) blending with lactose or polyol, a lactose derivative, is investigated by Fourier transform infrared, differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and stress–strain tests. The IR spectra of PAA/lactose blends exist shifting around 1700 cm and 3400 cm −1 , i…
Optical properties of SrBi2Ta2O9 (SBT) ferroelectric thin films were investigated by spectroscopic ellipsometry at room temperature in the 1.5–5.5 eV spectral range. The films were grown on platinized silicon (Pt/Ti/SiO2/Si) with a Bi/Sr ratio (x) range from 1.2 to 2.8 by pulsed-laser deposition. The measured pseudodi…
This letter describes the promising technique of micromachining using the properties of electrochemical etching of (100)-oriented n-type silicon in a hydrofluoric acid electrolyte. The technique is based on electropolishing of a wafer except for areas where vertical structures are needed and does not require a periodi…
Abstract In this work, the influence of temperature, molecular weight ( M̄ n ), and molecular weight dispersity (MWD) on the surface tension of polystyrene (PS) was evaluated using the pendant drop method. The influence of temperature on the surface tension of isotatic polypropylene (i‐PP) and of linear low‐density po…
We have developed an ultrafast, light-scattering spectroscopic system combining a conventional microscope with a pump–probe setup. We successfully measured the surface plasmon resonance band for the individual gold particles with a mean radius of 40 nm. The results on the pump–probe experiment demonstrate that both th…
The same method used to determine ${\ensuremath{\sigma}}^{*}$ excitations in the x-ray-absorption spectra of organic molecules is applied to analyze the structure of the ${\ensuremath{\sigma}}^{*}$ band in the x-ray absorption spectra of amorphous carbon $(a\ensuremath{-}\mathrm{C})$ films. The analysis assumes that o…