On the Joint Distribution of Energy Levels of Random Schroedinger Operators

We consider operators with random potentials on graphs, such as the lattice version of the random Schroedinger operator. The main result is a general bound on the probabilities of simultaneous occurrence of eigenvalues in specified distinct intervals, with the corresponding eigenfunctions being separately localized within prescribed regions. The bound generalizes the Wegner estimate on the density of states. The analysis proceeds through a new multiparameter spectral averaging principle

RADIOACTIVE WASTE DISPOSAL PROJECTS. IDAHO CHEMICAL PROCESSING PLANT TECHNICAL PROGRESS REPORT FOR JULY-SEPTEMBER 1959

The progress of extensive laboratory and pilot plant investigations on the fluidized bed process for the con version of radioactive liquid wastes to solids is reported. These studies are directed toward obtaining information on the dynamics of fluidized bed operation, the removal of volatile fission products and solids particles from gases, the development of equipment and operating techniques, and the various long term disposal aspects of all radioactive wastes. Laboratory studies on the removal of volatile ruthenium from a simulated calciner off-gas showed the removal efficiency of silica gel to decrease with successive wetting and drying cycles. Electrostatic precipitators were found to have a higher removal efficiency for solid particles (alumina) when a wetted wall rather than a dry wall type was used. Tests to determine the distribution of ruthenium in a pilot plant calciner were performed. Pilot plant data on particle growth in a fluidized bed were compared with theoretical equations. Operating experience with a NaK heat transfer system, and with liquid flow controllers is reported. The results of a series of qualitative tests to determine the likelihood of an explosive reaction should NaK leak into a fluidized bed calciner indicated that such a reaction is unlikely. A NaK leak that occurred at a welded junction was attributed to thermal overstressing of the metal and not due to corrosion. Calcium fluoride-impregnated Teflon was found to be a superior gasketing material, both chemically and mechanically, to pure Teflon. A literature survey on the chemistry of zirconium in a calcination process suggested the possibility of calcination in contact with silica and a laboratory unit is being installed to study the process. The hydraulics of a pulsed plate solids-liquid contactor and its associated equipment were determined. A preliminary investigation was started of the possibility of using metallizing techniques to surface coat solid particles and thereby reduce the leaching of fission products when contacted with ground water. Construction of a demonstrational fluidized bed calciner was approximately half completed; however, the national steel strike has slowed the construction schedule and the completion date cannot be estimated until the strike is settled. Process and equipment reviews of the facility and the results of thermal conductivity measurements on Idaho sands are reported. (auth

Localization Bounds for Multiparticle Systems

We consider the spectral and dynamical properties of quantum systems of $n$ particles on the lattice $\Z^d$, of arbitrary dimension, with a Hamiltonian which in addition to the kinetic term includes a random potential with iid values at the lattice sites and a finite-range interaction. Two basic parameters of the model are the strength of the disorder and the strength of the interparticle interaction. It is established here that for all $n$ there are regimes of high disorder, and/or weak enough interactions, for which the system exhibits spectral and dynamical localization. The localization is expressed through bounds on the transition amplitudes, which are uniform in time and decay exponentially in the Hausdorff distance in the configuration space. The results are derived through the analysis of fractional moments of the $n$-particle Green function, and related bounds on the eigenfunction correlators

Upper bounds on the density of states of single Landau levels broadened by Gaussian random potentials

We study a non-relativistic charged particle on the Euclidean plane R^2 subject to a perpendicular constant magnetic field and an R^2-homogeneous random potential in the approximation that the corresponding random Landau Hamiltonian on the Hilbert space L^2(R^2) is restricted to the eigenspace of a single but arbitrary Landau level. For a wide class of Gaussian random potentials we rigorously prove that the associated restricted integrated density of states is absolutely continuous with respect to the Lebesgue measure. We construct explicit upper bounds on the resulting derivative, the restricted density of states. As a consequence, any given energy is seen to be almost surely not an eigenvalue of the restricted random Landau Hamiltonian.Comment: 16 pages, to appear in "Journal of Mathematical Physics

A small new species of Crenicichla Heckel, 1840 from middle rio Xingu, Brazil (Teleostei: Cichlidae)

A new species of Crenicichla is described from the middle rio Xingu and tributaries, upstream from Volta Grande do Xingu. The largest specimen measured 47.8 mm SL. The new species can be distinguished from all other Crenicichla species by the combination of the following character states: presence of serrae on supracleithrum (diagnostic of Crenicichla wallacii species group), large caudal blotch centrally located on caudal lateral line (shared with C. urosema and C. virgatula), vertical dark stripes on the caudal fin and up to three series of teeth on premaxilla and maxilla (vs. more than four series of teeth). The new species described herein is the eleventh species of Crenicichla listed from the rio Xingu basin. Similarities of color pattern among small species of Crenicichla is discussed. © 2015, Sociedade Brasileira de Ictiologia

Nuclear incident at the Idaho Chemical Processing Plant on January 25, 1961 : report of the investigating committee /

"TID-4500 (16th ed.)"--Cover."IDO-10036 Health & Safety"--Cover."June 1, 1961."Mode of access: Internet