Materials Literature
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By using 193 nm laser photolysis and cavity ring-down spectroscopy to produce and monitor the propargyl radical (CH 2 CCH), the self-reaction and oxygen termolecular association rate coefficients for the propargyl radical were measured at 295 K between total pressures of 300 Pa and 13300 Pa (2.25 and 100 Torr) in Ar,…
Three-dimensional cross-slipped core structures of (a/2)[110] screw dislocations in model fcc structures are simulated using lattice statics within the embedded-atom method (EAM) formalism. Two parametric EAM potentials fitted to the elastic and structural properties of fcc Ni were used for the simulations. The two- a…
An x-ray absorption fine-structure (XAFS) spectroscopy beamline, BL01B1, was installed at a bending magnet source at SPring-8 and has been open to users since October 1997. It was designed for XAFS experiments covering a wide energy range. Position tables and automatical control programs were established to adjust the…
The dielectric properties of PZT and barium titanate based ferroelectric ceramics have been determined over a wide range of electric field strength (0.05 to 4.0 kV mm−1) by analysis of P-E (polarisation-electric field) hysteresis data. Three different types of dielectric behaviour were identified, depending on the app…
The study of thermoelectric materials has recently been revived as an active research field, in part due to the recent demonstration of enhancement in the thermoelectric figure of merit of a two-dimensional (2D) PbTe quantum well system, relative to its three-dimensional (3D) bulk counterpart. Calculations suggest tha…
The particle size effect on the coordination number in nanoparticles is much stronger for more distant coordination shells than for the first nearest neighbor shell. We show, using the EXAFS analysis of carbon-supported Pt and Pt-Ru nanoparticles, that it is possible to analyze the structure of mono-and heteroatomie p…
The use of lead-free materials in piezoelectric ceramics has recently become a very important issue in environmental protection of the earth. Some lead-free piezoelectric materials, namely bismuth sodium titanate, (Bi1/2Na1/2)TiO3 (BNT) – based solid solution ceramics, such as (1-a)BNT-a·BaTiO3 [BNBT], (1-b)BNT-b·NaNb…
The 4,4‘-disubstituted azobenzene ligands HL a - d react with [(η 3 -C 4 H 7 )Pt(μ-Cl)] 2 to give the dinuclear cycloplatinated complexes [(L a - d )Pt(μ-Cl)] 2, which are easily converted to their mononuclear Pt(II) acetylacetonate derivatives [(L a - d )Pt(acac)]. Oxidative addition to the square-planar Pt(II) compl…
Novel pH-sensitive polymers were synthesized by copolymerizing a monomer derivatized from 4-amino-N-[4,6-dimethyl-2-pyrimidinyl]benzene sulfonamide with N,N-dimethylacrylamide. The linear copolymers showed pH-sensitive solubility, while chemically crosslinked hydrogels exhibit a relatively sharp transition in swelling…
The use of hyperbranched polymers (HBPs) as a processing aid for linear low density polyethylene (LLDPE) was investigated. Various generation (or pseudo-generation) HBPs were used which had either 16 carbon atom alkanes or a mixture of 20/22 carbon atom alkanes on the end groups. In addition, the degree of end group s…
Various graphitic phases of ${\mathrm{C}}_{3}{\mathrm{N}}_{4}$ are examined using the local-density approximation plane-wave-pseudopotential approach. These are three forms of p graphite and the $P6\ifmmode\bar\else\textasciimacron\fi{}m2$ graphite structure. Each differs only in planar stacking and character of plana…
The wafer flexure technique was used to characterize the d31 coefficient of a number of sol–gel and radio frequency (rf) sputtered lead zirconate titanate (PZT) thin films with thicknesses between 0.6 and 3 μm. Typical d31 values for well-poled 52/48 sol–gel films were found to be between −50 and −60 pC/N. The rf sput…
The structural and thermodynamic properties of a two-dimensional binary mixture of soft discs are reported over a range of temperatures down to large supercoolings using constant NPT molecular dynamics simulations. It is shown that the four orders of magnitude increase in the structural relaxation time is not accompan…
When expressed by pathogenic bacteria, Zn2+-beta-lactamases induce resistance to most beta-lactam antibiotics. A possible strategy to fight these bacteria would be a combined therapy with non-toxic inhibitors of Zn2+-beta-lactamases together with standard antibiotics. For this purpose, it is important to verify that t…
In this work, X‐ray diffractometry and scanning electron microscopy techniques were used to study the incorporation of yttrium in BaTiO 3 , with the following nominal compositions: (Ba 1‐ x Y x )TiO 3 (0.015 ≤ to x ≤ to 0.08), (Ba 1‐ x Y x )Ti 1‐ x /4 ‐(□ Ti ) x /4 O 3 (0.005 ≤ to x ≤ to 0.1), and Ba(Ti 1‐ y Y y )O 3‐…
An electric double layer capacitor (EDLC) was prepared with an activated carbon powder electrode with poly(vinylidene fluoridehexafluoropropylene) (PVdF‐HFP) based gel electrolyte. Ethylene carbonate (EC) and propylene carbonate (PC) were used as plasticizer and tetraethylammonium tetrafluoroborate was used as thesupp…
Starting from the well known analytical formula for the eddy current losses in electrical steel laminations, saturation and edge effects are studied by means of 1D and 2D finite element models of a single lamination. A novel method for directly including the laminated core energy dissipation in a time stepped 2D model…
Computer simulations showed that the elastic modulus of the cell layer relative to the elastic modulus of the extracellular layers predicted the effectiveness of different force-generating mechanisms for sea urchin primary invagination [L. A. Davidson, M. A. R. Koehl, R. Keller, and G. F. Oster (1995) Development 121,…
Aqueous solutions containing 10 -3 M luminol and varying concentrations of hydrogen peroxide are irradiated with 20 kHz ultrasound at 50 °C. The intensity of sonogenerated chemiluminescence (SCL) is shown to increase linearly with ultrasound power and to be strongly pH dependent, reaching a maximum at pH 12. For pH <…
Low reflectivity (“black”) surface treatments for space-borne infrared systems are reviewed. The uses of black surfaces in general, as well as for specific space-borne applications are discussed. Compositions of a wide variety of surface treatments with examples of experimental data to characterize performances are pr…