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Application of remote sensing to state and local government (ARSIG)
Progress of ARSIG projects is reported and the impact of the projects upon policy decision within Arizona is discussed.
NASA Earth Resources Survey Symposium. Volume 2-B: Special session presentations. Coastal zone management, state and local users, user services
Applications of remote sensing technology to environmental problems and resources management are presented.
Remote sensing procurement package: A technical guide for state and local governments
The guide provides the tools and techniques for procuring remote sensing products and services. It is written for administrators, procurement officials and line agency staff who are directly involved in identifying information needs; defining remote sensing project requirements; soliciting and evaluating contract responses and negotiating, awarding, and administering contracts.
Pilot study of the domestic information display system in state and local government
An interactive computer based system that can retrieve a wide range of data (demographic, environmental, socio-economic, etc.,) from a large data base and display these data for different geographic units in the form of choropleth maps was developed. The system was designed to display statistical information in a geographic format for national policy makers.
Charge Carrier Transport in Iron Pyrite Thin Films: Disorder-Induced Variable-Range Hopping
Here, the origin of p-type conductivity and the mechanism responsible for low carrier mobility were investigated in pyrite (FeS 2 ) thin films. Temperature-dependent resistivity measurements (10-400 K) were performed on polycrystalline and nanostructured thin films prepared by three different methods: (1) spray pyrolysis, (2) hot-injection synthesized and spin-coated nanocubes, and (3) pulsed laser deposition. The films have a high hole density (10 18 -10 19 ) cm -3 and low mobility (0.1-4 cm 2 V -1 s -1 ) regardless of the method used for their preparation. The charge transport mechanism is determined to be thermally activated conduction (TAC) at near room temperature, with Mott-type variable-range hopping (VRH) of holes via localized states occurring at lower temperatures. The density functional theory (DFT) predicts that sulfur vacancy induces localized defect states within the band gap and the charge remains localized around the defect. The data indicates that the electronic properties including hopping transport in pyrite thin films can be correlated to sulfur vacancy-related defects. The results provide insights into the electronic properties of pyrite thin films and their implications for charge transport.
Crystal and Electronic Structure of High-Temperature Superconductive Layered Cuprates in Temperature Interval 100–300 K
For two HTSC materials, Y{sub 1−x}Ca{sub x}Ba{sub 2}Cu{sub 3}O{sub 6.7} and Tl{sub 0.8}Hg{sub 0.2}Ba{sub 2}Ca{sub 2}Cu{sub 3}O{sub 8.15}, their crystal structure has been studied earlier in the temperature interval 100–300 K. It is shown that for both compounds, the height of CuO{sub 5} pyramids has a minimum in temperature interval from ∼ 150 to ∼ 250 K. The electronic structure is calculated using first principles based on the obtained data of crystal structure. It is revealed that a decrease in the CuO{sub 5} pyramid height leads to the appearance of the electronic state density peak with an energy of 0.3–0.4 eV under Fermi level. Localized states of barium and apical oxygen make the main contribution to this peak. By reduction the temperature below ∼ 150 K, these localized electronic states disappear, and under continuous cooling, the superconductivity appears.
Light-weight cache coherence for data processors with limited data sharing
A data processing system includes a plurality of processors, local memories associated with a corresponding processor, and at least one inter-processor link. In response to a first processor performing a load or store operation on an address of a corresponding local memory that is not currently in the local cache, a local cache allocates a first cache line and encodes a local state with the first cache line. In response to a load operation from an address of a remote memory that is not currently in the local cache, the local cache allocates a second cache line and encodes a remote state with the second cache line. The first processor performs subsequent loads and stores on the first cache line in the local cache in response to the local state, and subsequent loads from the second cache line in the local cache in response to the remote state.
Localization in disordered materials - Binary alloys
Electron states localization in disordered binary alloys, describing band structure
Origin of the Large Bandgap Bowing in Highly Mismatched Semiconductor Alloys
We use a combination of optical and soft x-ray fluorescence techniques to investigate the composition dependence of the band edge energies in ZnSe(1-x)Te(x) and ZnS(1-x)Te(x) alloys. The results reveal entirely different origins of the large bandgap bowing for alloys with small and large Te content. On the Te-rich side, the reduction of the bandgap is well explained by the band anticrossing interaction between the Se or S localized states and the ZnTe conduction band states. On the Se or S-rich side, an interaction between the localized Te states and the degenerate GAMMA valence bands of ZnSe or ZnS is responsible for the bandgap reduction and the rapid increase of the spin-orbit splitting with increasing Te concentration. Results of soft x-ray fluorescence experiments provide direct evidence for the valence band anticrossing interaction. The bandgap bowing over the entire composition range is accounted for by a linear interpolation between the conduction band anticrossing and valence band anticrossing models.
Classification of matrix product states with a local (gauge) symmetry
Matrix Product States (MPS) are a particular type of one dimensional tensor network states, that have been applied to the study of numerous quantum many body problems. One of their key features is the possibility to describe and encode symmetries on the level of a single building block (tensor), and hence they provide a natural playground for the study of symmetric systems. In particular, recent works have proposed to use MPS (and higher dimensional tensor networks) for the study of systems with local symmetry that appear in the context of gauge theories. In this work we classify MPS which exhibit local invariance under arbitrary gauge groups. We study the respective tensors and their structure, revealing known constructions that follow known gauging procedures, as well as different, other types of possible gauge invariant states. - Highlights: • Structure of tensors generating states (MPS) with local symmetry is determined. • Three types of states analyzed: matter, pure gauge field and their combined state. • Structure of gauge field Hilbert space derived from local symmetry assumption. • New gauge invariant states described, not the result of gauging a global symmetry.
Temperature dependence of electronic band transition in Mn-doped SnO{sub 2} nanocrystalline films determined by ultraviolet-near-infrared transmittance spectra
Highlights: Black-Right-Pointing-Pointer The temperature dependence of electronic structures has been investigated by transmittance spectra from 5.3 to 300 K. Black-Right-Pointing-Pointer The optical band gap shows a red shift with increasing Mn composition and decreases with the temperature. Black-Right-Pointing-Pointer The band gap narrowing parameter [E{sub g}(5.3 K)-E{sub g}(300 K)] linearly decreases with the Mn composition. Black-Right-Pointing-Pointer There are two temperature regimes for the Urbach energy. -- Abstract: Mn-doped SnO{sub 2} (SMO) nanocrystalline films with the composition from 2.5 to 12.5% have been prepared on quartz substrates by pulsed laser deposition. The temperature dependence of electronic structures and optical constants in the SMO films have been investigated by transmittance spectra from 5.3 to 300 K. Optical response functions have been extracted by fitting the transmittance spectra in the photon energy range of 0.5-6.5 eV with the Adachi's model. It was found that the absorption edge presents a red-shift trend with increasing Mn composition, and the optical band gap (OBG) is varied between 4.22 and 3.44 eV. Moreover, as the Mn composition increases, the temperature dependence of OBG becomes weaker. The band gap narrowing value [(5.3 K)-(300 K)] has been reduced from 98 to 3 meV and linearly decreases with the Mn composition. The phenomena could be attributed to the transition from low doping level SnO{sub 2} band-like states to Mn-related localized states. Moreover, the Urbach energy shows the degree of the structural disorder, which could be explained by an empirical formulas in different temperature regimes.
An X-ray Absorption Spectroscopy Study of the Cathodic Discharge of Ag2VO2PO4: Geometric and Electronic Structure Characterization of Intermediate Phases and Mechanistic Insights
Bimetallic phosphorus oxides have emerged as attractive candidates for use as cathode materials in the next generation of lithium-based batteries owing to the operation of multielectron transfer processes and thermochemical stabilities conferred by the incorporation of phosphate groups. In particular silver vanadium phosphorus oxide, Ag{sub 2}VO{sub 2}PO{sub 4}, shows a much desired in situ conductivity enhancement upon discharge resulting in inherently high power capability with minimal conductive additives needed. However, the amorphization of Ag{sub 2}VO{sub 2}PO{sub 4} during electrochemical discharge precludes the use of standard diffraction tools to monitor changes in the local electronic and geometric structure. Here, we have utilized a combination of V K-, V L-, Ag K-, and O K-edge X-ray absorption fine structure spectroscopy to determine the local vanadium and silver oxidation states, local coordination geometry, and stoichiometry for Ag{sub 2}VO{sub 2}PO{sub 4} samples with varying extents of electrochemical lithiation. Soft X-ray V L- and O K-edge measurements provide a detailed orbital-specific picture of changes in vanadium electronic structure upon discharge.
Dual density wave state in liquid Ga
Liquid Ga is considered to be in a mixed state of metallic and covalent local states, and shows complex behavior, similar to those of other polyvalent Group III–V elements on the Periodic Table, such as Si, Ge, Sn, and Bi. We studied liquid Ga by inelastic neutron scattering to obtain the pair-distribution function. We found that the structure of liquid Ga has the medium-range order characterized by two overlapping density waves (DWs), one originating from ionic repulsion and the other due to electronic driving force to create charge DWs. We suggest that the dual DW state is naturally elucidated by the DW theory, rather than the widely used Ornstein–Zernike theory.
Nonequilibrium Diffusional Phase Transformations in Alloys Induced by Migration of Grain Boundaries and Dislocations
The main scenarios of nonequilibrium diffusional transformations induced by moving defects (dislocations, grain boundaries) in alloys under severe plastic deformation are considered. It has been shown that the phase state locally changes in the area of a defect where thermodynamic properties of alloy are locally changed, and the attained state is frozen after the displacement of a defect due to the difference between the rates of bulk diffusion and diffusion on a defect. For this reason, an alloy shifts from the state of its thermodynamic equilibrium under treatment, thus different nonequilibrium states, such as the disordering of alloy, the dissolution of equilibrium phase precipitates, the appearance of nonequilibrium phases, and the formation of regular structures, are possible depending on the type of the system. These effects may take place if the treatment of an alloy is performed at moderate temperatures, when diffusion is frozen in the bulk and rather active on defects. The phenomena of phase and structural instability developing under severe plastic deformation at moderate temperatures are considered within the framework of the proposed model.
Dangling bonds and dislocations in semiconductors.
Dangling bonds and dislocations in semiconductors, noting existence of core charge dependent localized state in gap caused by local decrease in atom density
A New Consolidated Storage Facility for Used Nuclear Fuel in Andrews County, Texas - 16418
On February 6, 2015, Waste Control Specialists LLC (WCS) announced its plan to file a license application with the U.S. Nuclear Regulatory Commission (NRC) to construct and operate a Consolidated Interim Storage Facility (CISF). Upon issuance of the license, WCS would be authorized to receive Used Nuclear Fuel (UNF) and reactor related Greater Than Class C Low Level Radioactive Waste (referred hence forth as UNF) at the CISF in late 2020. WCS based its decision to license a CISF based on strong support from the State of Texas and the local community's willingness to host such a facility in Andrews County, Texas. WCS' decision to license a CISF in a supportive community is consistent with the consent-based licensing approach recommended by the Blue Ribbon Commission on America's Nuclear Future. WCS intends to use existing technology developed by AREVA and NAC International that have already been approved by the NRC to transport UNF from existing commercial nuclear reactors across the nation for interim storage at its 14,000 acre site in Andrew County, Texas. In the pre-application licensing meetings held with the NRC, WCS underscored that UNF would be removed first from the shutdown decommissioned reactor sites and transported to the CISF. Approximately eighty percent of the UNF currently residing at the shutdown decommissioned reactor sites can be safely placed into the storage systems developed by AREVA and NAC International that are currently licensed by the NRC. WCS plans to store up to 40,000 Metric Tons of Heavy Metal (MTHM) at the CISF that would be constructed in eight phases over the next 20 years. WCS intends to submit its license application for the CISF to the NRC by April 2016. The license application will request authorization to possess up to 5,000 MTHM of UNF for Phase One which can accommodate storing the fuel located at over ten shutdown decommissioned reactor sites. As discussed with the NRC, the license application will be developed following NRC regulatory guidance to comply with the technical requirements specified in Title 10 of the Code of Federal Regulations (CFR) Part 72, Licensing Requirements for the Independent Storage of Spent Nuclear Fuel, High-Level Radioactive Waste, and Reactor-Related Greater Than Class C Waste. In addition, to filing the license application, WCS is also seeking legislative changes to the Nuclear Waste Policy Act of 1982 requiring the U.S. Department of Energy (DOE) to take title of the UNF at the commercial nuclear reactor sites. Under such legislative changes, the DOE would also be responsible for the transport of UNF to the CISF. In addition to preparing the CISF License Application, WCS and its partners AREVA and NAC International are prepared to work with DOE to facilitate the development of the UNF transportation infrastructure in the timeframe needed to support CISF operations. The WCS site and technical approach give it several advantages which uniquely position it to become the first successful commercial CISF in the U.S. These advantages include: broad consent-based support at the local, state, and Congressional level; an operating waste disposal site with an existing transportation infrastructure; and the use of already licensed systems to address 80% of the UNF currently in dry storage at shutdown sites in the U.S. WCS firmly believes this initiative will provide an economically viable option for consolidated interim storage of UNF until a permanent geologic repository becomes available. (authors)
Electron and hole transport in ambipolar, thin film pentacene transistors
Solution-processed, ambipolar, thin-film pentacene field-effect transistors were employed to study both electron and hole transport simultaneously in a single, organic solid-state device. Electron and hole mobilities were extracted from the respective unipolar saturation regimes and show thermally activated behavior and gate voltage dependence. We fit the gate voltage dependent saturation mobility to a power law to extract the characteristic Meyer-Neldel (MN) energy, a measure of the width of the exponential distribution of localized states extending into the energy gap of the organic semiconductor. The MN energy is ∼78 and ∼28 meV for electrons and holes, respectively, which reflects a greater density of localized tail states for electrons than holes. This is consistent with the lower measured electron than hole mobility. For holes, the well-behaved linear regime allows for four-point probe measurement of the contact resistance independent mobility and separate characterization of the width of the localized density of states, yielding a consistent MN energy of 28 meV.