Materials Literature
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The effects of the electron-electron interactions in a graphene layer are investigated. It is shown that short-range couplings are irrelevant and scale towards zero at low energies, due to the vanishing of density of states at the Fermi level. Topological disorder enhances the density of states and can lead to instabi…
A model of NMR spin-lattice relaxation in quasicrystals is presented, which takes into account two important quasicrystals-specific features: (i) the critical nature of the electronic states and (ii) the phonon-assisted hopping nature of electronic conduction within the self-similar quasiperiodic structure of hierarch…
A computer simulation study has been performed to investigate the intrinsic defects in ${\mathrm{PbWO}}_{4}$ (PWO). The interatomic potentials were empirically fit to the known crystal properties. Calculations reveal that PbO nonstoichiometry dominates the intrinsic defects in PWO, whereas the oxygen Frenkel defects w…
By using a Raman microscope, we show that it is possible to probe the conformational states in protein crystals and crystal fragments under growth conditions (in hanging drops). The flavin cofactor in the enzyme para-hydroxybenzoate hydroxylase can assume two conformations: buried in the protein matrix ("in") or essen…
Water, benzene, and nitrogen were adsorbed on Al-MCM-41 molecular sieves, both unmodified and modified via controlled deposition of coke, and adsorption isotherms were determined. The mechanism of adsorption most probably includes multilayer adsorption at lower relative pressures, followed by capillary condensation. I…
We present a simple Fokker-Planck model for the evolution of the number of atoms and the spatial distribution in a ${\mathrm{CO}}_{2}$ laser trap which is loaded from a magneto-optical trap (MOT). Deep ${\mathrm{CO}}_{2}$ laser traps can achieve very high densities, but reach equilibrium slowly compared to shallow tra…
Mesoscopic hollow spheres of ceramic materials whose interior surfaces were functionalized by nanoscopic objects were generated by templating sol−gel precursors against three-dimensional arrays of polystyrene beads whose surfaces had been derivatized with submonolayers of the nanoscopic objects.
The ${\mathrm{Bi}}_{1\ensuremath{-}x}{\mathrm{Ca}}_{x}{\mathrm{MnO}}_{3}$ system is known to exhibit charge ordering for a much broader range of x than the ${\mathrm{La}}_{1\ensuremath{-}x}{\mathrm{Ca}}_{x}{\mathrm{MnO}}_{3}$ system. However, the properties of ${\mathrm{Bi}}_{1\ensuremath{-}x}{\mathrm{Ca}}_{x}{\mathrm…
The electrical resistivity, thermoelectric power and electronic thermal conductivity of simple (isotropic) metals are studied in a uniform way. Starting from results of a variational solution of the Boltzmann equation, a generalized Matthiessen rule is used in order to superpose the inelastic (or not) electron-phonon…
Nanotubular materials inspired by crystalline diborides such as AlB_2 are proposed. The atomic structure, in particular the basic chemical question of where to put Al atoms in order to stabilize nanotubular Al-B systems, is investigated using density-functional calculations for prototype systems. The optimized tubular…
A first-principle theory for the effective dielectric permittivity in metallic mesostructures is developed. This theory, in particular, takes into account the skin effect, which is important in practical applications of metal structures.
<div class="htmlview paragraph">Recently, ASMT has developed a process of making monolithic metal oxide thin-wall structures from mechanically assembled metal preforms, whose shape and internal configuration are retained in the (oxidation) process. Because metallic designs can be extremely diverse, the same vari…
This paper describes the third generation of the partial zero emission vehicle (P-ZEV) technology originally adopted on the Nissan Sentra CA sold in California. The 2000 Nissan Sentra CA became the world's first gasoline-fueled car to qualify for P-ZEV credits from the California Air Resources Board (CARB). The third-…
Two effects of rich-spike duration on NOx-storing have been analyzed. The first one, that NOx-storing speed decreases as rich-spike duration increases, is explained as the influence of NOx diffusion in wash-coat layer, which is quantified by a simple mathematical expression for NOx-storing rate. The second one, a pecu…
<div class="htmlview paragraph">Recent developments in design of composite armor for lightweight ground vehicle applications is discussed. Composite integral armor (CIA) is a multi-functional hybrid material system that has been successfully demonstrated in the Composite Armored Vehicle. A typical CIA hull consi…
<div class="htmlview paragraph">Strict legislation standards for automotive emission limits (e.g. ULEV, SULEV), which target for HC conversion rates beyond 99 %, impose the necessity to dramatically shorten catalyst Light-Off time and increase catalytic efficiency through improved catalytic converter heat-up. Es…
<div class="htmlview paragraph">NOx adsorber has already been used for the after-treatment system of series production vehicle installed with a lean burn or direct injection engine [<span class="xref">1</span>,<span class="xref">2</span>,<span class="xref">3</span>]. In order…
In view of practical handling of single-walled carbon nanotubes (SWNTs), here we present cutting procedures and spontaneous ordering of SWNTs deposited on highly oriented pyrolytic graphite (HOPG). Purified SWNTs were cut by ultrasonication in H2SO4/HNO3 mixture and further in de-ionized water. Thus, prepared short SW…
We report torque magnetization measurements in regions of the mixed state phase diagram ( $\mathbf{B}\ensuremath{\sim}{\ensuremath{\mu}}_{o}{\mathbf{H}}_{c2}$ and ${T}_{c}{/10}^{3}$) of the organic superconductor $\ensuremath{\kappa}\ensuremath{-}(\mathrm{ET}{)}_{2}\mathrm{Cu}(\mathrm{NCS}{)}_{2}$, where quantum fluct…
<div class="htmlview paragraph">Though very important for the system performance, the dynamic behavior of the catalytic converter has mainly been neglected in the design of exhaust emission control systems. Since the major dynamic effects stem from the oxygen storage capabilities of the catalytic converter, a no…