Hydrogen bond strengthening induces fluorescence quenching of PRODAN derivative by turning on twisted intramolecular charge transfer

NASA Astrophysics Data System (ADS)

Yang, Yonggang; Li, Donglin; Li, Chaozheng; Liu, YuFang; Jiang, Kai

2017-12-01

Researchers have proposed different effective mechanisms of hydrogen bonding (HB) on the fluorescence of 6-propionyl-2-dimethylaminonaphthalene (PRODAN) and its derivatives. Herein, excited state transition and dynamics analysis confirm that the fluorescence of PD (a derivative of PRODAN with ethyl replaced by 3-hydroxy-2,2-dimethylpropan) emits from the planar intramolecular charge transfer (PICT) state rather than twist ICT (TICT) state, because the fluorescence emission and surface hopping from the TICT state to the twist ground (T-S0) state is energy forbidden. Nevertheless, the strengthening of intramolecular-HB (intra-HB) and intermolecular-HB (inter-HB) of PD-(methanol)2 smooth the pathway of surface hopping from TICT to T-S0 state and the external conversion going to planar ground state by decreasing the energy difference of the two states. This smoothing changes the fluorescence state of PD-(methanol)2 to the TICT state in which fluorescence emission does not occur but surface hopping, leading to the partial fluorescence quenching of PD in methanol solvent. This conclusion is different from previous related reports. Moreover, the inter-HB strengthening of PD-methanol in PICT state induces the cleavage of intra-HB and a fluorescence red-shift of 54 nm compared to PD. This red-shift increases to 66 nm for PD-(methanol)2 for the strengthening of the one intra-HB and two inter-HBs. The dipole moments of PD-methanol and PD-(methanol)2 respectively increase about 10.3D and 8.1D in PICT state compared to PD. The synergistic effect of intra-HB and inter-HB induces partial quenching of PD in methanol solvent by turning on the TICT state and fluorescence red-shift. This work gives a reasonable description on the fluorescence red-shift and partial quenching of PD in methanol solvent, which will bring insight into the study of spectroscopic properties of molecules owning better spectral characteristics.

Hydrogen bond strengthening induces fluorescence quenching of PRODAN derivative by turning on twisted intramolecular charge transfer.

PubMed

Yang, Yonggang; Li, Donglin; Li, Chaozheng; Liu, YuFang; Jiang, Kai

2017-12-05

Researchers have proposed different effective mechanisms of hydrogen bonding (HB) on the fluorescence of 6-propionyl-2-dimethylaminonaphthalene (PRODAN) and its derivatives. Herein, excited state transition and dynamics analysis confirm that the fluorescence of PD (a derivative of PRODAN with ethyl replaced by 3-hydroxy-2,2-dimethylpropan) emits from the planar intramolecular charge transfer (PICT) state rather than twist ICT (TICT) state, because the fluorescence emission and surface hopping from the TICT state to the twist ground (T-S 0 ) state is energy forbidden. Nevertheless, the strengthening of intramolecular-HB (intra-HB) and intermolecular-HB (inter-HB) of PD-(methanol) 2 smooth the pathway of surface hopping from TICT to T-S 0 state and the external conversion going to planar ground state by decreasing the energy difference of the two states. This smoothing changes the fluorescence state of PD-(methanol) 2 to the TICT state in which fluorescence emission does not occur but surface hopping, leading to the partial fluorescence quenching of PD in methanol solvent. This conclusion is different from previous related reports. Moreover, the inter-HB strengthening of PD-methanol in PICT state induces the cleavage of intra-HB and a fluorescence red-shift of 54nm compared to PD. This red-shift increases to 66nm for PD-(methanol) 2 for the strengthening of the one intra-HB and two inter-HBs. The dipole moments of PD-methanol and PD-(methanol) 2 respectively increase about 10.3D and 8.1D in PICT state compared to PD. The synergistic effect of intra-HB and inter-HB induces partial quenching of PD in methanol solvent by turning on the TICT state and fluorescence red-shift. This work gives a reasonable description on the fluorescence red-shift and partial quenching of PD in methanol solvent, which will bring insight into the study of spectroscopic properties of molecules owning better spectral characteristics. Copyright © 2017 Elsevier B.V. All rights reserved.

Optical coupling of cold atoms to a levitated nanosphere

NASA Astrophysics Data System (ADS)

Montoya, Cris; Witherspoon, Apryl; Fausett, Jacob; Lim, Jason; Kitching, John; Geraci, Andrew

2017-04-01

Cooling mechanical oscillators to their quantum ground state enables the study of quantum phenomena at macroscopic levels. In many cases, the temperature required to cool a mechanical mode to the ground state is below what current cryogenic systems can achieve. As an alternative to cooling via cryogenic systems, it has been shown theoretically that optically trapped nanospheres could reach the ground state by sympathetically cooling the spheres via cold atoms. Such cooled spheres can be used in quantum limited sensing and matter-wave interferometry, and could also enable new hybrid quantum systems where mechanical oscillators act as transducers. In our setup, optical fields are used to couple a sample of cold Rubidium atoms to a nanosphere. The sphere is optically levitated in a separate vacuum chamber, while the atoms are trapped in a 1-D optical lattice and cooled using optical molasses. This work is partially supported by NSF, Grant No. PHY-1506431.

Sub-Doppler slit jet infrared spectroscopy of astrochemically relevant cations: Symmetric (ν1) and antisymmetric (ν6) NH stretching modes in ND2H2+

NASA Astrophysics Data System (ADS)

Chang, Chih-Hsuan; Nesbitt, David J.

2018-01-01

Sub-Doppler infrared rovibrational transitions in the symmetric (v1) and antisymmetric (v6) NH stretch modes of the isotopomerically substituted ND2H2+ ammonium cation are reported for the first time in a slit jet discharge supersonic expansion spectrometer. The partially H/D substituted cation is generated by selective isotopic exchange of ND3 with H2O to form NHD2, followed by protonation with H3+ formed in the NHD2/H2/Ne slit-jet discharge expansion environment. Rotational assignment for ND2H2+ is confirmed rigorously by four line ground state combination differences, which agree to be within the sub-Doppler precision in the slit jet (˜9 MHz). Observation of both b-type (ν1) and c-type (ν6) bands enables high precision determination of the ground and vibrationally excited state rotational constants. From an asymmetric top Watson Hamiltonian analysis, the ground state constants are found to be A″ = 4.856 75(4) cm-1, B″ = 3.968 29(4) cm-1, and C″ = 3.446 67(6) cm-1, with band origins at 3297.5440(1) and 3337.9050(1) cm-1 for the v1 and v6 modes, respectively. This work permits prediction of precision microwave/mm-wave transitions, which should be invaluable in facilitating ongoing spectroscopic searches for partially deuterated ammonium cations in interstellar clouds and star-forming regions of the interstellar medium.

75 FR 54116 - Notice of Intent To Grant Partially Exclusive License of the United States Patent Application No...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-09-03

... coatings, side dressing, lawn application and starter ground cover) and applications in the fields of soil... particulate removal, metal and inorganic chelation in soils and water, soil erosion, road stabilizer, and dust... synthetic, petroleum-based polymers for soil amendment applications to achieve increased soil strength...

Categorical QSAR models for skin sensitization based on local lymph node assay measures and both ground and excited state 4D-fingerprint descriptors

NASA Astrophysics Data System (ADS)

Liu, Jianzhong; Kern, Petra S.; Gerberick, G. Frank; Santos-Filho, Osvaldo A.; Esposito, Emilio X.; Hopfinger, Anton J.; Tseng, Yufeng J.

2008-06-01

In previous studies we have developed categorical QSAR models for predicting skin-sensitization potency based on 4D-fingerprint (4D-FP) descriptors and in vivo murine local lymph node assay (LLNA) measures. Only 4D-FP derived from the ground state (GMAX) structures of the molecules were used to build the QSAR models. In this study we have generated 4D-FP descriptors from the first excited state (EMAX) structures of the molecules. The GMAX, EMAX and the combined ground and excited state 4D-FP descriptors (GEMAX) were employed in building categorical QSAR models. Logistic regression (LR) and partial least square coupled logistic regression (PLS-CLR), found to be effective model building for the LLNA skin-sensitization measures in our previous studies, were used again in this study. This also permitted comparison of the prior ground state models to those involving first excited state 4D-FP descriptors. Three types of categorical QSAR models were constructed for each of the GMAX, EMAX and GEMAX datasets: a binary model (2-state), an ordinal model (3-state) and a binary-binary model (two-2-state). No significant differences exist among the LR 2-state model constructed for each of the three datasets. However, the PLS-CLR 3-state and 2-state models based on the EMAX and GEMAX datasets have higher predictivity than those constructed using only the GMAX dataset. These EMAX and GMAX categorical models are also more significant and predictive than corresponding models built in our previous QSAR studies of LLNA skin-sensitization measures.

Water Resources Data, West Virginia, Water Year 2003

USGS Publications Warehouse

Ward, S.M.; Rosier, M.T.; Crosby, G.R.

2004-01-01

Water-resources data for the 2003 water year for West Virginia consists of records of stream discharge, reservoir and ground-water levels, and water quality of streams and ground-water wells. This report contains discharge records for 70 streamflow-gaging stations; discharge records provided by adjacent states for 8 streamflow-gaging stations; annual maximum discharge at 16 crest-stage partial-record stations; stage records for 6 detention reservoirs; water-quality records for 2 stations; and water-level records for 8 observation wells. Locations of streamflow, detention reservoir, and water-quality stations are shown on figure 4. Locations of ground-water observation wells are shown on figure 5. Additional water data were collected at various sites, not involved in the systematic data-collection program, and are published as miscellaneous sites. These data represent that part of the National Water Data System collected by the U.S. Geological Survey and cooperating State and Federal agencies in West Virginia.

Water resources data-West Virginia, water year 2004

USGS Publications Warehouse

Ward, S.M.; Rosier, M.T.; Crosby, G.R.

2005-01-01

Water-resources data for the 2004 water year for West Virginia consist of records of stream discharge, reservoir and ground-water levels, and water quality of streams and ground-water wells. This report contains discharge records for 65 streamflow-gaging stations; discharge records provided by adjacent states for 8 streamflow-gaging stations; annual maximum discharge at 17 crest-stage partial-record stations; stage records for 14 detention reservoirs; water-quality records for 2 stations; and water-level records for 10 observation wells. Locations of streamflow, detention reservoir, and water-quality stations are shown on figure 4. Locations of ground-water observation wells are shown on figure 5. Additional water-quality data were collected at various sites, not involved in the systematic data collection program, and are published as miscellaneous sites. These data represent that part of the National Water Data System collected by the U.S. Geological Survey and cooperating State and Federal agencies in West Virginia.

Single-photon cesium Rydberg excitation spectroscopy using 318.6-nm UV laser and room-temperature vapor cell.

PubMed

Wang, Jieying; Bai, Jiandong; He, Jun; Wang, Junmin

2017-09-18

We demonstrate a single-photon Rydberg excitation spectroscopy of cesium (Cs) atoms in a room-temperature vapor cell. Cs atoms are excited directly from 6S 1/2 ground state to nP 3/2 (n = 70 - 100) Rydberg states with a 318.6 nm ultraviolet (UV) laser, and Rydberg excitation spectra are obtained by transmission enhancement of a probe beam resonant to Cs 6S 1/2 , F = 4 - 6P 3/2 , F' = 5 transition as partial population on F = 4 ground state are transferred to Rydberg state. Analysis reveals that the observed spectra are velocity-selective spectroscopy of Rydberg state, from which the amplitude and linewidth influenced by lasers' Rabi frequency have been investigated. Fitting to energies of Cs nP 3/2 (n = 70 -100) states, the determined quantum defect is 3.56671(42). The demodulated spectra can also be employed as frequency references to stabilize the UV laser frequency to specific Cs Rydberg transition.

Many-body Green’s function theory for electron-phonon interactions: The Kadanoff-Baym approach to spectral properties of the Holstein dimer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Säkkinen, Niko; Peng, Yang; Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, 14195 Berlin-Dahlem

2015-12-21

We present a Kadanoff-Baym formalism to study time-dependent phenomena for systems of interacting electrons and phonons in the framework of many-body perturbation theory. The formalism takes correctly into account effects of the initial preparation of an equilibrium state and allows for an explicit time-dependence of both the electronic and phononic degrees of freedom. The method is applied to investigate the charge neutral and non-neutral excitation spectra of a homogeneous, two-site, two-electron Holstein model. This is an extension of a previous study of the ground state properties in the Hartree (H), partially self-consistent Born (Gd) and fully self-consistent Born (GD) approximationsmore » published in Säkkinen et al. [J. Chem. Phys. 143, 234101 (2015)]. Here, the homogeneous ground state solution is shown to become unstable for a sufficiently strong interaction while a symmetry-broken ground state solution is shown to be stable in the Hartree approximation. Signatures of this instability are observed for the partially self-consistent Born approximation but are not found for the fully self-consistent Born approximation. By understanding the stability properties, we are able to study the linear response regime by calculating the density-density response function by time-propagation. This amounts to a solution of the Bethe-Salpeter equation with a sophisticated kernel. The results indicate that none of the approximations is able to describe the response function during or beyond the bipolaronic crossover for the parameters investigated. Overall, we provide an extensive discussion on when the approximations are valid and how they fail to describe the studied exact properties of the chosen model system.« less

Competing charge density wave and antiferromagnetism of metallic atom wires in GaN(10 1 ¯ ) and ZnO(10 1 ¯ )

NASA Astrophysics Data System (ADS)

Kang, Yoon-Gu; Kim, Sun-Woo; Cho, Jun-Hyung

2017-12-01

Low-dimensional electron systems often show a delicate interplay between electron-phonon and electron-electron interactions, giving rise to interesting quantum phases such as the charge density wave (CDW) and magnetism. Using the density-functional theory (DFT) calculations with the semilocal and hybrid exchange-correlation functionals as well as the exact-exchange plus correlation in the random-phase approximation (EX + cRPA), we systematically investigate the ground state of the metallic atom wires containing dangling-bond (DB) electrons, fabricated by partially hydrogenating the GaN(10 1 ¯0 ) and ZnO(10 1 ¯0 ) surfaces. We find that the CDW or antiferromagnetic (AFM) order has an electronic energy gain due to a band-gap opening, thereby being more stabilized compared to the metallic state. Our semilocal DFT calculation predicts that both DB wires in GaN(10 1 ¯0 ) and ZnO(10 1 ¯0 ) have the same CDW ground state, whereas the hybrid DFT and EX + cRPA calculations predict the AFM ground state for the former DB wire and the CDW ground state for the latter one. It is revealed that more localized Ga DB electrons in GaN(10 1 ¯0 ) prefer the AFM order, while less localized Zn DB electrons in ZnO(10 1 ¯0 ) the CDW formation. Our findings demonstrate that the drastically different ground states are competing in the DB wires created on the two representative compound semiconductor surfaces.

Sympathetic cooling of nanospheres with cold atoms

NASA Astrophysics Data System (ADS)

Montoya, Cris; Witherspoon, Apryl; Ranjit, Gambhir; Casey, Kirsten; Kitching, John; Geraci, Andrew

2016-05-01

Ground state cooling of mesoscopic mechanical structures could enable new hybrid quantum systems where mechanical oscillators act as transducers. Such systems could provide coupling between photons, spins and charges via phonons. It has recently been shown theoretically that optically trapped dielectric nanospheres could reach the ground state via sympathetic cooling with trapped cold atoms. This technique can be beneficial in cases where cryogenic operation of the oscillator is not practical. We describe experimental advances towards coupling an optically levitated dielectric nanosphere to a gas of cold Rubidium atoms. The sphere and the cold atoms are in separate vacuum chambers and are coupled using a one-dimensional optical lattice. This work is partially supported by NSF, Grant Nos. PHY-1205994,PHY-1506431.

Many-body Green’s function theory for electron-phonon interactions: Ground state properties of the Holstein dimer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Säkkinen, Niko; Leeuwen, Robert van; Peng, Yang

2015-12-21

We study ground-state properties of a two-site, two-electron Holstein model describing two molecules coupled indirectly via electron-phonon interaction by using both exact diagonalization and self-consistent diagrammatic many-body perturbation theory. The Hartree and self-consistent Born approximations used in the present work are studied at different levels of self-consistency. The governing equations are shown to exhibit multiple solutions when the electron-phonon interaction is sufficiently strong, whereas at smaller interactions, only a single solution is found. The additional solutions at larger electron-phonon couplings correspond to symmetry-broken states with inhomogeneous electron densities. A comparison to exact results indicates that this symmetry breaking is stronglymore » correlated with the formation of a bipolaron state in which the two electrons prefer to reside on the same molecule. The results further show that the Hartree and partially self-consistent Born solutions obtained by enforcing symmetry do not compare well with exact energetics, while the fully self-consistent Born approximation improves the qualitative and quantitative agreement with exact results in the same symmetric case. This together with a presented natural occupation number analysis supports the conclusion that the fully self-consistent approximation describes partially the bipolaron crossover. These results contribute to better understanding how these approximations cope with the strong localizing effect of the electron-phonon interaction.« less

Use of Microgravity to Assess the Effects of El Nino on Ground-Water Storage in Southern Arizona

USGS Publications Warehouse

Parker, John T.C.; Pool, Donald R.

1998-01-01

The availability of ground water is of extreme importance in areas, such as southern Arizona, where it is the main supply for agricultural, industrial, or domestic purposes. Where ground-water use exceeds recharge, monitoring is critical for managing water supplies. Typically, monitoring has been done by measuring water levels in wells; however, this technique only partially describes ground-water conditions in a basin. A new application of geophysical technology is enabling U.S. Geological Survey (USGS) scientists to measure changes in the amount of water in an aquifer using a network of microgravity stations. This technique enables a direct measurement of ground-water depletion and recharge. In Tucson, Arizona, residents have relied solely upon ground water for most of their needs since the 19th century. Water levels in some wells in the Tucson area have declined more than 200 ft in the past 50 years. Similar drops in water levels have occurred elsewhere in Arizona. In response to the overdrafting of ground water, the State of Arizona passed legislation designed to attain 'safe yield,' which is defined as a balance between ground-water withdrawals and annual recharge of aquifers. To monitor progress in complying with the legislation, ground-water withdrawals are measured and estimated, and annual recharge is estimated. The Tucson Basin and Avra Valley are two ground-water basins that form the Tucson Active Management Area (TAMA), which by State statute must attain 'safe yield' by the year 2025.

Static electric dipole polarizability of lithium atoms in Debye plasmas

NASA Astrophysics Data System (ADS)

Ning, Li-Na; Qi, Yue-Ying

2012-12-01

The static electric dipole polarizabilities of the ground state and n <= 3 excited states of a lithium atom embedded in a weekly coupled plasma environment are investigated as a function of the plasma screening radium. The plasma screening of the Coulomb interaction is described by the Debye—Hückel potential and the interaction between the valence electron and the atomic core is described by a model potential. The electron energies and wave functions for both the bound and continuum states are calculated by solving the Schrödinger equation numerically using the symplectic integrator. The oscillator strengths, partial-wave, and total static dipole polarizabilities of the ground state and n <= 3 excited states of the lithium atom are calculated. Comparison of present results with those of other authors, when available, is made. The results for the 2s ground state demonstrated that the oscillator strengths and the static dipole polarizabilities from np orbitals do not always increase or decrease with the plasma screening effect increasing, unlike that for hydrogen-like ions, especially for 2s→3p transition there is a zero value for both the oscillator strength and the static dipole polarizability for screening length D = 10.3106a0, which is associated with the Cooper minima.

Ground state and magnetic phase transitions of the spin Lieb nanolattice: Monte Carlo simulations

NASA Astrophysics Data System (ADS)

Masrour, R.; Jabar, A.

2018-02-01

We study the ground state and magnetic properties of the spin Lieb nanolattice with three lattice sites with spins (S = 2 , σ = 1 / 2 , q = 3 / 2) using Monte Carlo simulations. The ground state phase diagrams of the Lieb nanolattice have been studied. The phase diagrams show some key features: coexistence between regions, points where six, eight and ten states can coexist. The total and partial magnetization of each sublattice is given and the corresponding magnetic susceptibility is also found. The variation of total magnetization with the exchange interaction RSq and Rσq of the Lieb nanolattice with three lattice sites with spins (S , σ , q) has been studied. Moreover, the total magnetization versus the fields Δ /JSσ of the Lieb nanolattice with three lattice sites with spins (S , σ , q) are established for several values of Rσq and Rsq. Magnetic hysteresis cycles of the Lieb nanolattice with three lattice sites with spins (S , σ , q) are found for several values of Rsq and temperature. We show that the superparamagnetism behaviour appears for a weak coupling value between S and q thus around the transition temperature.

Feeding of Rh and Ag isomers in fast-neutron-induced reactions

DOE PAGES

Fotiades, Nikolaos; Devlin, Matthew James; Nelson, Ronald Owen; ...

2016-10-17

In (n,n') reactions on stable Ir and Au isotopes in the mass A=190 region, the experimentally established feeding of the isomers relative to the feeding of the corresponding ground states increases with increasing neutron energy, up to the neutron energy where the (n,2n) reaction channel opens up, and then decreases. In order to check for similar behavior in the mass A=100 region, the feeding of isomers and ground states in fast-neutron-induced reactions on stable isotopes in this mass region was studied. This is of especial interest for Rh which can be used as a radiochemical detector. Here, excited states weremore » studied using the (n,n'γ), (n,2nγ), and (n,3nγ) reactions on 103Rh and 109Ag. A germanium detector array for γ-ray detection and the broad-spectrum pulsed neutron source of the Los Alamos Neutron Science Center's Weapons Neutron Research facility were used for the measurement. The energy of the incident neutrons was determined using the time-of-flight technique. Absolute partial γ-ray cross sections were measured for 57 transitions feeding isomers and ground states in 101,102,103Rh and 107,108,109Ag. The feeding of the isomers was found to be very similar in the corresponding reaction channels and it is compared to the feeding determined for the ground states. In conclusion, the opening of reaction channels at higher neutron energies removes angular momentum from the residual nucleus and reduces the population of the higher-spin isomers relative to the feeding of the lower-spin ground states. Similar behavior was observed in the mass A=190 region in the feeding of higher-spin isomers, but the reverse behavior was observed in 176Lu with a lower-spin isomer and a higher-spin ground state.« less

Feeding of Rh and Ag isomers in fast-neutron-induced reactions

NASA Astrophysics Data System (ADS)

Fotiades, N.; Devlin, M.; Nelson, R. O.; Kawano, T.; Carroll, J. J.

2016-10-01

Background: In (n ,n' ) reactions on stable Ir and Au isotopes in the mass A =190 region, the experimentally established feeding of the isomers relative to the feeding of the corresponding ground states increases with increasing neutron energy, up to the neutron energy where the (n ,2 n ) reaction channel opens up, and then decreases. Purpose: In order to check for similar behavior in the mass A =100 region, the feeding of isomers and ground states in fast-neutron-induced reactions on stable isotopes in this mass region was studied. This is of especial interest for Rh which can be used as a radiochemical detector. Methods: Excited states were studied using the (n ,n'γ ), (n ,2 n γ ), and (n ,3 n γ ) reactions on 103Rh and 109Ag. A germanium detector array for γ -ray detection and the broad-spectrum pulsed neutron source of the Los Alamos Neutron Science Center's Weapons Neutron Research facility were used for the measurement. The energy of the incident neutrons was determined using the time-of-flight technique. Results: Absolute partial γ -ray cross sections were measured for 57 transitions feeding isomers and ground states in 101,102,103Rh and 107,108,109Ag. The feeding of the isomers was found to be very similar in the corresponding reaction channels and it is compared to the feeding determined for the ground states. Conclusions: The opening of reaction channels at higher neutron energies removes angular momentum from the residual nucleus and reduces the population of the higher-spin isomers relative to the feeding of the lower-spin ground states. Similar behavior was observed in the mass A =190 region in the feeding of higher-spin isomers, but the reverse behavior was observed in 176Lu with a lower-spin isomer and a higher-spin ground state.

Feeding of Rh and Ag isomers in fast-neutron-induced reactions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fotiades, Nikolaos; Devlin, Matthew James; Nelson, Ronald Owen

In (n,n') reactions on stable Ir and Au isotopes in the mass A=190 region, the experimentally established feeding of the isomers relative to the feeding of the corresponding ground states increases with increasing neutron energy, up to the neutron energy where the (n,2n) reaction channel opens up, and then decreases. In order to check for similar behavior in the mass A=100 region, the feeding of isomers and ground states in fast-neutron-induced reactions on stable isotopes in this mass region was studied. This is of especial interest for Rh which can be used as a radiochemical detector. Here, excited states weremore » studied using the (n,n'γ), (n,2nγ), and (n,3nγ) reactions on 103Rh and 109Ag. A germanium detector array for γ-ray detection and the broad-spectrum pulsed neutron source of the Los Alamos Neutron Science Center's Weapons Neutron Research facility were used for the measurement. The energy of the incident neutrons was determined using the time-of-flight technique. Absolute partial γ-ray cross sections were measured for 57 transitions feeding isomers and ground states in 101,102,103Rh and 107,108,109Ag. The feeding of the isomers was found to be very similar in the corresponding reaction channels and it is compared to the feeding determined for the ground states. In conclusion, the opening of reaction channels at higher neutron energies removes angular momentum from the residual nucleus and reduces the population of the higher-spin isomers relative to the feeding of the lower-spin ground states. Similar behavior was observed in the mass A=190 region in the feeding of higher-spin isomers, but the reverse behavior was observed in 176Lu with a lower-spin isomer and a higher-spin ground state.« less

Water Resources Data, Alabama, Water Year 2002

USGS Publications Warehouse

Pearman, J.L.; Stricklin, V.E.; Psinakis, W.L.

2003-01-01

Water resources data for the 2002 water year for Alabama consist of records of stage, discharge, and water quality of streams; stages and contents of lakes and reservoirs; and water levels in wells. This report includes records on both surface and ground water in the State. Specifically, it contains: (1) discharge records for 131 streamflow-gaging stations, for 41 partial-record or miscellaneous streamflow stations; (2) stage and content records for 14 lakes and reservoirs and stage at 47 stations; (3) water-quality records for 12 streamflow-gaging stations, for 17 ungaged streamsites, and for 2 precipitation stations; (4) water temperature at 14 surfacewater stations; (5) specific conductance and dissolved oxygen at 12 stations; (6) turbidity at 3 stations; (7) sediment data at 6 stations; (8) water-level records for 2 recording observation wells; and (9) water-quality records for 21 ground-water stations. Also included are lists of active and discontinued continuous-record surface-water-quality stations, and partial-record and miscellaneous surface-water-quality stations. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating Federal, State, and local agencies in Alabama.

Water Resources Data, Alabama, Water Year 2003

USGS Publications Warehouse

Psinakis, W.L.; Lambeth, D.S.; Stricklin, V.E.; Treece, M.W.

2004-01-01

Water resources data for the 2003 water year for Alabama consist of records of stage, discharge, and water quality of streams; stages and contents of lakes and reservoirs; and water levels in wells. This report includes records on both surface and ground water in the State. Specifically, it contains: (1) discharge records for 130 streamflow-gaging stations, for 29 partial-record or miscellaneous streamflow stations; (2) stage and content records for 14 lakes and reservoirs and stage at 46 stations; (3) water-quality records for 12 streamflow-gaging stations, for 29 ungaged streamsites, and for 1 precipitation stations; (4) water temperature at 12 surfacewater stations; (5) specific conductance and dissolved oxygen at 12 stations; (6) turbidity at 3 stations; (7) sediment data at 6 stations; (8) water-level records for 2 recording observation wells; and (9) water-quality records for 9 ground-water stations. Also included are lists of active and discontinued continuous-record surface-water-quality stations, and partial-record and miscellaneous surface-water-quality stations. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating Federal, State, and local agencies in Alabama.

Water Resources Data, Alabama, Water Year 2004

USGS Publications Warehouse

Psinakis, W.L.; Lambeth, D.S.; Stricklin, V.E.; Treece, M.W.

2005-01-01

Water resources data for the 2004 water year for Alabama consist of records of stage, discharge, and water quality of streams; stages and contents of lakes and reservoirs; and water levels in wells. This report includes records on both surface and ground water in the State. Specifically, it contains: (1) discharge records for 131 streamflow-gaging stations, for 19 partial-record or miscellaneous streamflow stations; (2) stage and content records for 16 lakes and reservoirs and stage at 44 stations; (3) water-quality records for 21 streamflow-gaging stations, for 11 ungaged streamsites, and for 1 precipitation stations; (4) water temperature at 20 surface-water stations; (5) specific conductance and dissolved oxygen at 20 stations; (6) turbidity at 5 stations; (7) sediment data at 6 stations; (8) water-level records for 2 recording observa-tion wells; and (9) water-quality records for 6 ground-water stations. Also included are lists of active and discontinued continuous-record surface-water-quality stations, and partial-record and miscellaneous sur-face-water-quality stations. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating Federal, State, and local agencies in Alabama.

Water Resources Data, Alabama, Water Year 2005

USGS Publications Warehouse

Psinakis, W.L.; Lambeth, D.S.; Stricklin, V.E.; Treece, M.W.

2006-01-01

Water resources data for the 2005 water year for Alabama consist of records of stage, discharge, and water quality of streams; stages and contents of lakes and reservoirs; and water levels in wells. This report includes records on both surface and ground water in the State. Specifically, it contains: (1) discharge records for 131 streamflow-gaging stations and 23 partial-record or miscellaneous streamflow stations; (2) stage and content records for 14 lakes and reservoirs and stage at 44 stations; (3) water-quality records for 125 streamflow-gaging stations and 67 ungaged streamsites; (4) water temperature at 179 surface-water stations; (5) specific conductance at 180 stations; (6) dissolved oxygen at 17 stations; (7) turbidity at 52 stations; (8) sediment data at 2 stations; (9) water-level records for 2 recording observation wells; and (10) water-quality records for 6 ground-water stations. Also included are lists of active and discontinued continuous-record surface-water-quality stations, and partial-record and miscellaneous surface- water-quality stations. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating Federal, State, and local agencies in Alabama.

π-Electron-system-layered polymer: through-space conjugation and properties as a single molecular wire.

PubMed

Morisaki, Yasuhiro; Ueno, Shizue; Saeki, Akinori; Asano, Atsushi; Seki, Shu; Chujo, Yoshiki

2012-04-02

[2.2]Paracyclophane-based through-space conjugated oligomers and polymers were prepared, in which poly(p-arylene-ethynylene) (PAE) units were partially π-stacked and layered, and their properties in the ground state and excited state were investigated in detail. Electronic interactions among PAE units were effective through at least ten units in the ground state. Photoexcited energy transfer occurred from the stacked PAE units to the end-capping PAE moieties. The electrical conductivity of the polymers was estimated using the flash-photolysis time-resolved microwave conductivity (FP-TRMC) method and investigated together with time-dependent density functional theory (TD-DFT) calculations, showing that intramolecular charge carrier mobility through the stacked PAE units was a few tens of percentage larger than through the twisted PAE units. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Charge transfer to ground-state ions produces free electrons

PubMed Central

You, D.; Fukuzawa, H.; Sakakibara, Y.; Takanashi, T.; Ito, Y.; Maliyar, G. G.; Motomura, K.; Nagaya, K.; Nishiyama, T.; Asa, K.; Sato, Y.; Saito, N.; Oura, M.; Schöffler, M.; Kastirke, G.; Hergenhahn, U.; Stumpf, V.; Gokhberg, K.; Kuleff, A. I.; Cederbaum, L. S.; Ueda, K

2017-01-01

Inner-shell ionization of an isolated atom typically leads to Auger decay. In an environment, for example, a liquid or a van der Waals bonded system, this process will be modified, and becomes part of a complex cascade of relaxation steps. Understanding these steps is important, as they determine the production of slow electrons and singly charged radicals, the most abundant products in radiation chemistry. In this communication, we present experimental evidence for a so-far unobserved, but potentially very important step in such relaxation cascades: Multiply charged ionic states after Auger decay may partially be neutralized by electron transfer, simultaneously evoking the creation of a low-energy free electron (electron transfer-mediated decay). This process is effective even after Auger decay into the dicationic ground state. In our experiment, we observe the decay of Ne2+ produced after Ne 1s photoionization in Ne–Kr mixed clusters. PMID:28134238

Spin polarized and density modulated phases in symmetric electron-electron and electron-hole bilayers.

PubMed

Kumar, Krishan; Moudgil, R K

2012-10-17

We have studied symmetric electron-electron and electron-hole bilayers to explore the stable homogeneous spin phase and the feasibility of inhomogeneous charge-/spin-density ground states. The former is resolved by comparing the ground-state energies in states of different spin polarizations, while the latter is resolved by searching for a divergence in the wavevector-dependent static charge/spin susceptibility. For this endeavour, we have used the dielectric approach within the self-consistent mean-field theory of Singwi et al. We find that the inter-layer interactions tend to change an abrupt spin-polarization transition of an isolated layer into a nearly gradual one, even though the partially spin-polarized phases are not clearly stable within the accuracy of our calculation. The transition density is seen to decrease with a reduction in layer spacing, implying a suppression of spin polarization by inter-layer interactions. Indeed, the suppression shows up distinctly in the spin susceptibility computed from the spin-polarization dependence of the ground-state energy. However, below a critical layer spacing, the unpolarized liquid becomes unstable against a charge-density-wave (CDW) ground state at a density preceding full spin polarization, with the transition density for the CDW state increasing on further reduction in the layer spacing. Due to attractive e-h correlations, the CDW state is found to be more pronounced in the e-h bilayer. On the other hand, the static spin susceptibility diverges only in the long-wavelength limit, which simply represents a transition to the homogeneous spin-polarized phase.

Hydrogeologic data for the Big River-Mishnock River stream-aquifer system, central Rhode Island

USGS Publications Warehouse

Craft, P.A.

2001-01-01

Hydrogeology, ground-water development alternatives, and water quality in the BigMishnock stream-aquifer system in central Rhode Island are being investigated as part of a long-term cooperative program between the Rhode Island Water Resources Board and the U.S. Geological Survey to evaluate the ground-water resources throughout Rhode Island. The study area includes the Big River drainage basin and that portion of the Mishnock River drainage basin upstream from the Mishnock River at State Route 3. This report presents geologic data and hydrologic and water-quality data for ground and surface water. Ground-water data were collected from July 1996 through September 1998 from a network of observation wells consisting of existing wells and wells installed for this study, which provided a broad distribution of data-collection sites throughout the study area. Streambed piezometers were used to obtain differences in head data between surface-water levels and ground-water levels to help evaluate stream-aquifer interactions throughout the study area. The types of data presented include monthly ground-water levels, average daily ground-water withdrawals, drawdown data from aquifer tests, and water-quality data. Historical water-level data from other wells within the study area also are presented in this report. Surface-water data were obtained from a network consisting of surface-water impoundments, such as ponds and reservoirs, existing and newly established partial-record stream-discharge sites, and synoptic surface-water-quality sites. Water levels were collected monthly from the surface-water impoundments. Stream-discharge measurements were made at partial-record sites to provide measurements of inflow, outflow, and internal flow throughout the study area. Specific conductance was measured monthly at partial-record sites during the study, and also during the fall and spring of 1997 and 1998 at 41 synoptic sites throughout the study area. General geologic data, such as estimates of depth to bedrock and depth to water table, as well as indications of underlying geologic structure, were obtained from geophysical surveys. Site-specific geologic data were collected during the drilling of observation wells and test holes. These data include depth to bedrock or refusal, depth to water table, and lithologic information.

Cavity as a Source of Conformational Fluctuation and High-Energy State: High-Pressure NMR Study of a Cavity-Enlarged Mutant of T4Lysozyme

PubMed Central

Maeno, Akihiro; Sindhikara, Daniel; Hirata, Fumio; Otten, Renee; Dahlquist, Frederick W.; Yokoyama, Shigeyuki; Akasaka, Kazuyuki; Mulder, Frans A.A.; Kitahara, Ryo

2015-01-01

Although the structure, function, conformational dynamics, and controlled thermodynamics of proteins are manifested by their corresponding amino acid sequences, the natural rules for molecular design and their corresponding interplay remain obscure. In this study, we focused on the role of internal cavities of proteins in conformational dynamics. We investigated the pressure-induced responses from the cavity-enlarged L99A mutant of T4 lysozyme, using high-pressure NMR spectroscopy. The signal intensities of the methyl groups in the 1H/13C heteronuclear single quantum correlation spectra, particularly those around the enlarged cavity, decreased with the increasing pressure, and disappeared at 200 MPa, without the appearance of new resonances, thus indicating the presence of heterogeneous conformations around the cavity within the ground state ensemble. Above 200 MPa, the signal intensities of >20 methyl groups gradually decreased with the increasing pressure, without the appearance of new resonances. Interestingly, these residues closely matched those sensing a large conformational change between the ground- and high-energy states, at atmospheric pressure. 13C and 1H NMR line-shape simulations showed that the pressure-induced loss in the peak intensity could be explained by the increase in the high-energy state population. In this high-energy state, the aromatic side chain of F114 gets flipped into the enlarged cavity. The accommodation of the phenylalanine ring into the efficiently packed cavity may decrease the partial molar volume of the high-energy state, relative to the ground state. We suggest that the enlarged cavity is involved in the conformational transition to high-energy states and in the volume fluctuation of the ground state. PMID:25564860

Cavity as a source of conformational fluctuation and high-energy state: high-pressure NMR study of a cavity-enlarged mutant of T4 lysozyme.

PubMed

Maeno, Akihiro; Sindhikara, Daniel; Hirata, Fumio; Otten, Renee; Dahlquist, Frederick W; Yokoyama, Shigeyuki; Akasaka, Kazuyuki; Mulder, Frans A A; Kitahara, Ryo

2015-01-06

Although the structure, function, conformational dynamics, and controlled thermodynamics of proteins are manifested by their corresponding amino acid sequences, the natural rules for molecular design and their corresponding interplay remain obscure. In this study, we focused on the role of internal cavities of proteins in conformational dynamics. We investigated the pressure-induced responses from the cavity-enlarged L99A mutant of T4 lysozyme, using high-pressure NMR spectroscopy. The signal intensities of the methyl groups in the (1)H/(13)C heteronuclear single quantum correlation spectra, particularly those around the enlarged cavity, decreased with the increasing pressure, and disappeared at 200 MPa, without the appearance of new resonances, thus indicating the presence of heterogeneous conformations around the cavity within the ground state ensemble. Above 200 MPa, the signal intensities of >20 methyl groups gradually decreased with the increasing pressure, without the appearance of new resonances. Interestingly, these residues closely matched those sensing a large conformational change between the ground- and high-energy states, at atmospheric pressure. (13)C and (1)H NMR line-shape simulations showed that the pressure-induced loss in the peak intensity could be explained by the increase in the high-energy state population. In this high-energy state, the aromatic side chain of F114 gets flipped into the enlarged cavity. The accommodation of the phenylalanine ring into the efficiently packed cavity may decrease the partial molar volume of the high-energy state, relative to the ground state. We suggest that the enlarged cavity is involved in the conformational transition to high-energy states and in the volume fluctuation of the ground state. Copyright © 2015 Biophysical Society. Published by Elsevier Inc. All rights reserved.

Water resources data for Indiana, 1967

USGS Publications Warehouse

,

1968-01-01

The surface-water records for the 1967 water year for gaging stations, partial-record stations, and miscellaneous sites within the State of Indiana are given in this report. For convenience there are also included records for a few pertinent gaging stations in bordering States. The quality-of-water investigations of the U.S. Geological Survey are concerned with the chemical and physical characteristics of surface- and ground-water supplies of the Nation. The basic records for the 1967 water year for quality of surface waters within the State of Indiana are given in this report. For convenience and interest, there are also records for a few water quality stations in bordering states.

Water resources data for Indiana, 1966

USGS Publications Warehouse

,

1967-01-01

The surface-water records for the 1966 water year for gaging stations, partial-record stations, and miscellaneous sites within the State of Indiana are given in this report. For convenience there are also included records for a few pertinent gaging stations in bordering states. The quality-of-water investigations of the U.S. Geological Survey are concerned with the chemical and physical characteristics of surface- and ground-water supplies of the Nation. The basic records for the 1966 water year for quality of surface waters within the State of Indiana are given in this report. For convenience and interest, there are also records for a few water quality stations in bordering states.

Single-particle and collective motion in unbound deformed 39Mg

NASA Astrophysics Data System (ADS)

Fossez, K.; Rotureau, J.; Michel, N.; Liu, Quan; Nazarewicz, W.

2016-11-01

Background: Deformed neutron-rich magnesium isotopes constitute a fascinating territory where the interplay between collective rotation and single-particle motion is strongly affected by the neutron continuum. The unbound f p -shell nucleus 39Mg is an ideal candidate to study this interplay. Purpose: In this work, we predict the properties of low-lying resonant states of 39Mg, using a suite of realistic theoretical approaches rooted in the open quantum system framework. Method: To describe the spectrum and decay modes of 39Mg we use the conventional shell model, Gamow shell model, resonating group method, density matrix renormalization group method, and the nonadiabatic particle-plus-rotor model formulated in the Berggren basis. Results: The unbound ground state of 39Mg is predicted to be either a Jπ=7/2 - state or a 3/2 - state. A narrow Jπ=7/2 - ground-state candidate exhibits a resonant structure reminiscent of that of its one-neutron halo neighbor 37Mg, which is dominated by the f7 /2 partial wave at short distances and a p3 /2 component at large distances. A Jπ=3/2 - ground-state candidate is favored by the large deformation of the system. It can be associated with the 1/2 -[321 ] Nilsson orbital dominated by the ℓ =1 wave; hence its predicted width is large. The excited Jπ=1/2 - and 5 /2- states are expected to be broad resonances, while the Jπ=9/2 - and 11/2 - members of the ground-state rotational band are predicted to have very small neutron decay widths. Conclusion: We demonstrate that the subtle interplay between deformation, shell structure, and continuum coupling can result in a variety of excitations in an unbound nucleus just outside the neutron drip line.

Near ultraviolet photodissociation spectroscopy of Mn+(H2O) and Mn+(D2O)

NASA Astrophysics Data System (ADS)

Pearson, Wright L.; Copeland, Christopher; Kocak, Abdulkadir; Sallese, Zachary; Metz, Ricardo B.

2014-11-01

The electronic spectra of Mn+(H2O) and Mn+(D2O) have been measured from 30 000 to 35 000 cm-1 using photodissociation spectroscopy. Transitions are observed from the 7A1 ground state in which the Mn+ is in a 3d54s1 electronic configuration, to the 7B2 (3d54py) and 7B1 (3d54px) excited states with T0 = 30 210 and 32 274 cm-1, respectively. Each electronic transition has partially resolved rotational and extensive vibrational structure with an extended progression in the metal-ligand stretch at a frequency of ˜450 cm-1. There are also progressions in the in-plane bend in the 7B2 state, due to vibronic coupling, and the out-of-plane bend in the 7B1 state, where the calculation illustrates that this state is slightly non-planar. Electronic structure computations at the CCSD(T)/aug-cc-pVTZ and TD-DFT B3LYP/6-311++G(3df,3pd) level are also used to characterize the ground and excited states, respectively. These calculations predict a ground state Mn-O bond length of 2.18 Å. Analysis of the experimentally observed vibrational intensities reveals that this bond length decreases by 0.15 ± 0.015 Å and 0.14 ± 0.01 Å in the excited states. The behavior is accounted for by the less repulsive px and py orbitals causing the Mn+ to interact more strongly with water in the excited states than the ground state. The result is a decrease in the Mn-O bond length, along with an increase in the H-O-H angle. The spectra have well resolved K rotational structure. Fitting this structure gives spin-rotation constants ɛaa″ = -3 ± 1 cm-1 for the ground state and ɛaa' = 0.5 ± 0.5 cm-1 and ɛaa' = -4.2 ± 0.7 cm-1 for the first and second excited states, respectively, and A' = 12.8 ± 0.7 cm-1 for the first excited state. Vibrationally mediated photodissociation studies determine the O-H antisymmetric stretching frequency in the ground electronic state to be 3658 cm-1.

Identification of Ccr4-Not Complex Components as Regulators of Transition from Partial to Genuine Induced Pluripotent Stem Cells

PubMed Central

Kamon, Masayoshi; Katano, Miyuki; Hiraki-Kamon, Keiko; Hishida, Tomoaki; Nakachi, Yutaka; Mizuno, Yosuke; Okazaki, Yasushi; Suzuki, Ayumu; Hirasaki, Masataka; Ueda, Atsushi; Nishimoto, Masazumi; Kato, Hidemasa

2014-01-01

Somatic cells can be reprogrammed to induced pluripotent stem cells (iPSCs) by defined factors. However, substantial cell numbers subjected to iPSC induction stray from the main reprogramming route and are immortalized as partial iPSCs. These partial iPSCs can become genuine iPSCs by exposure to the ground state condition. However, such conversion is only possible for mouse partial iPSCs, and it is not applicable to human cells. Moreover, the molecular basis of this conversion is completely unknown. Therefore, we performed genome-wide screening with a piggyBac vector to identify genes involved in conversion from partial to genuine iPSCs. This screening led to identification of Cnot2, one of the core components of the Ccr4-Not complex. Subsequent analyses revealed that other core components, Cnot1 and Cnot3, also contributed to the conversion. Thus, our data have uncovered a novel role of core components of the Ccr4-Not complex as regulators of transition from partial to genuine iPSCs. PMID:24200330

Drop Tower Workshop

NASA Technical Reports Server (NTRS)

Urban, David

2013-01-01

Ground based microgravity facilities are an important proving ground for space experiments, ground-based research and space hardware risk mitigation. An overview of existing platforms will be discussed with an emphasis on drop tower capabilities. The potential for extension to partial gravity conditions will be discussed. Input will be solicited from attendees for their potential to use drop towers in the future and the need for enhanced capabilities (e.g. partial gravity)

Water resources data for Indiana, 1968

USGS Publications Warehouse

,

1969-01-01

The surface-water records for the 1968 water year for gaging stations, partial-record stations, and miscellaneous sties within the State of Indiana are given in this report. For convenience there are also included records for a few pertinent gaging stations in bordering States. Water-resources investigations of the U.S. Geological Survey include the collection of water quality data on the chemical and physical characteristics of surface- and ground-water supplies of the Nation. These data for the 1968 water year for the quality of surface water in Indiana are presented in this report.

Meson and baryon spectrum for QCD with two light dynamical quarks

NASA Astrophysics Data System (ADS)

Engel, Georg P.; Lang, C. B.; Limmer, Markus; Mohler, Daniel; Schäfer, Andreas

2010-08-01

We present results of meson and baryon spectroscopy using the Chirally Improved Dirac operator on lattices of size 163×32 with two mass-degenerate light sea quarks. Three ensembles with pion masses of 322(5), 470(4), and 525(7) MeV and lattice spacings close to 0.15 fm are investigated. Results for ground and excited states for several channels are given, including spin two mesons and hadrons with strange valence quarks. The analysis of the states is done with the variational method, including two kinds of Gaussian sources and derivative sources. We obtain several ground states fairly precisely and find radial excitations in various channels. Excited baryon results seem to suffer from finite size effects, in particular, at small pion masses. We discuss the possible appearance of scattering states, considering masses and eigenvectors. Partially quenched results in the scalar channel suggest the presence of a 2-particle state, however, in most channels we cannot identify them. Where available, we compare our results to results of quenched simulations using the same action.

Quadrupole splittings in the near-infrared spectrum of 14NH 3

DOE PAGES

Twagirayezu, Sylvestre; Hall, Gregory E.; Sears, Trevor J.

2016-10-13

Sub-Doppler, saturation dip, spectra of lines in the v 1 + v 3, v 1 + 2v 4 and v 3 + 2v 4 bands of 14NH 3 have been measured by frequency comb-referenced diode laser absorption spectroscopy. The observed spectral line widths are dominated by transit time broadening, and show resolved or partially-resolved hyperfine splittings that are primarily determined by the 14N quadrupole coupling. Modeling of the observed line shapes based on the known hyperfine level structure of the ground state of the molecule shows that, in nearly all cases, the excited state level has hyperfine splittings similar tomore » the same rotational level in the ground state. The data provide accurate frequencies for the line positions and easily separate lines overlapped in Doppler-limited spectra. The observed hyperfine splittings can be used to make and confirm rotational assignments and ground state combination differences obtained from the measured frequencies are comparable in accuracy to those obtained from conventional microwave spectroscopy. Furthermore, several of the measured transitions do not show the quadrupole hyperfine splittings expected based on their existing rotational assignments. Either the assignments are incorrect or the upper levels involved are perturbed in a way that affects the nuclear hyperfine structure.« less

ISOLATION AND PARTIAL CHARACTERIZATION OF AN ACID PHOSPHATASE ACTIVITY FROM SPIRODELA OLIGORHIZA

EPA Science Inventory

An acid phosphatase activity from the aquatic plant Spirodela oligorhiza (duckweed) was isolated and partially characterized. S. oligorhiza was grown in a hydroponic growth medium, harvested, and ground up in liquid nitrogen. The ground plant material was added to a biological ...

The excited spin-triplet state of a charged exciton in quantum dots.

PubMed

Molas, M R; Nicolet, A A L; Piętka, B; Babiński, A; Potemski, M

2016-09-14

We report on spectroscopic studies of resonances related to ladder of states of a charged exciton in single GaAlAs/AlAs quantum dot structures. Polarization-resolved photoluminescence, photoluminescence excitation and photon-correlation measurements were performed at low (T  =  4.2 K) temperature also in magnetic field applied in Faraday configuration. The investigated resonances are assigned to three different configurations of a positively charged exciton. Together with a singlet ground state and a conventional triplet state (involving an electron from the ground state electronic s-shell), an excited triplet state, which involved an electron from the excited electronic p-shell was identified in single dots. The appearance of an emission line related to the latter complex is due to a partially suppressed electron relaxation in the investigated dots. An analysis of this emission line allows us to scrupulously determine properties of the excited triplet state and compare them with those of the conventional triplet state. Both triplets exhibit similar patterns of anisotropic fine structure and Zeeman splitting, however their amplitudes significantly differ for those two states. Presented results emphasize the role of the symmetry of the electronic state on the properties of the triplet states of two holes  +  electron excitonic complex.

Protonation states and pH titration in the photocycle of photoactive yellow protein.

PubMed

Demchuk, E; Genick, U K; Woo, T T; Getzoff, E D; Bashford, D

2000-02-08

Photoactive yellow protein (PYP) undergoes a light-driven cycle of color and protonation states that is part of a mechanism of bacterial phototaxis. This article concerns functionally important protonation states of PYP and the interactions that stabilize them, and changes in the protonation state during the photocycle. In particular, the chromophore pK(a) is known to be shifted down so that the chromophore is negatively charged in the ground state (dark state) even though it is buried in the protein, while nearby Glu46 has an unusually high pK(a). The photocycle involves changes of one or both of these protonation states. Calculations of pK(a) values and protonation states using a semi-macroscopic electrostatic model are presented for the wild-type and three mutants, in both the ground state and the bleached (I(2)) intermediate state. Calculations allowing multiple H-bonding arrangements around the chromophore also have been carried out. In addition, ground-state pK(a) values of the chromophore have been measured by UV-visible spectroscopy for the wild-type and the same three mutants. Because of the unusual protonation states and strong electrostatic interactions, PYP represents a severe test of the ability of theoretical models to yield correct calculations of electrostatic interactions in proteins. Good agreement between experiment and theory can be obtained for the ground state provided the protein interior is assumed to have a relatively low dielectric constant, but only partial agreement between theory and experiment is obtained for the bleached state. We also present a reinterpretation of previously published data on the pH-dependence of the recovery of the ground state from the bleached state. The new analysis implies a pK(a) value of 6.37 for Glu46 in the bleached state, which is consistent with other available experimental data, including data that only became available after this analysis. The new analysis suggests that signal transduction is modulated by the titration properties of the bleached state, which are in turn determined by electrostatic interactions. Overall, the results of this study provide a quantitative picture of the interactions responsible for the unusual protonation states of the chromophore and Glu46, and of protonation changes upon bleaching.

The small impact of various partial charge distributions in ground and excited state on the computational Stokes shift of 1-methyl-6-oxyquinolinium betaine in diverse water models

NASA Astrophysics Data System (ADS)

Heid, Esther; Harringer, Sophia; Schröder, Christian

2016-10-01

The influence of the partial charge distribution obtained from quantum mechanics of the solute 1-methyl-6-oxyquinolinium betaine in the ground- and first excited state on the time-dependent Stokes shift is studied via molecular dynamics computer simulation. Furthermore, the effect of the employed solvent model — here the non-polarizable SPC, TIP4P and TIP4P/2005 and the polarizable SWM4 water model — on the solvation dynamics of the system is investigated. The use of different functionals and calculation methods influences the partial charge distribution and the magnitude of the dipole moment of the solute, but not the orientation of the dipole moment. Simulations based on the calculated charge distributions show nearly the same relaxation behavior. Approximating the whole solute molecule by a dipole results in the same relaxation behavior, but lower solvation energies, indicating that the time scale of the Stokes shift does not depend on peculiarities of the solute. However, the SPC and TIP4P water models show too fast dynamics which can be ascribed to a too large diffusion coefficient and too low viscosity. The calculated diffusion coefficient and viscosity for the SWM4 and TIP4P/2005 models coincide well with experimental values and the corresponding relaxation behavior is comparable to experimental values. Furthermore we found that for a quantitative description of the Stokes shift of the applied system at least two solvation shells around the solute have to be taken into account.

H-T Magnetic Phase Diagram of a Frustrated Triangular Lattice Antiferromagnet CuFeO 2

NASA Astrophysics Data System (ADS)

Mitsuda, Setsuo; Mase, Motoshi; Uno, Takahiro; Kitazawa, Hideaki; Katori, Hiroko

2000-01-01

By magnetization and specific heat measurements in an applied magnetic field up to 12 T, we obtained the magnetic field (H) versus temperature (T) phase diagram of a frustrated triangular lattice antiferromagnet (TLA), CuFeO2, where a partially disordered phase typical to Ising TLA exists as a thermally induced state for the 4-sublattice ground state as well as for the first-field-induced 5-sublattice-like state. The experimentally obtained H-T magnetic phase diagram is compared with that from Monte-Carlo simulation of a 2D Ising TLA model with competing exchange interactions up to 3rd neighbors.

Studying 10Be and 11Be Halo States through the (p,d) Single-Neutron Transfer Reaction

NASA Astrophysics Data System (ADS)

Kuhn, Keri; Sarazin, Fred; Tigress Collaboration; ^{(Pcb) 2} Collaboration

2017-09-01

One-neutron transfer reactions are being used to study single-particle neutron states in nuclei. For one-neutron halo nuclei, such as 11Be, the (p,d) reaction enables the removal of the halo neutron or of one of the core neutrons. This way, it is possible to simultaneously study the halo wavefunction of the 11Be ground-state but also a possible excited halo state in 10Be. The 11Be(p, d)10Be transfer reaction at 10 MeV/nucleon is being investigated at the TRIUMF-ISAC II facility with the Printed Circuit Board Based Charged Particle ((PCB)2) array inside the TRIUMF ISAC Gamma-Ray Escape-Suppressed Spectrometer (TIGRESS). The ground state and first excited state of 10Be can be directly identified using deuteron identification and kinematics from the charged particle array, while the four excited states in 10Be around 6 MeV, including the suspected halo state (2- state), are identified using coincident gamma rays from TIGRESS with the identified deuterons. Angular distributions for the 10Be populated states will be shown along with their FRESCO fits. This work is partially supported by the US Department of Energy through Grant/Contract No. DE-FG03- 93ER40789 (Colorado School of Mines).

Controlling state explosion during automatic verification of delay-insensitive and delay-constrained VLSI systems using the POM verifier

NASA Technical Reports Server (NTRS)

Probst, D.; Jensen, L.

1991-01-01

Delay-insensitive VLSI systems have a certain appeal on the ground due to difficulties with clocks; they are even more attractive in space. We answer the question, is it possible to control state explosion arising from various sources during automatic verification (model checking) of delay-insensitive systems? State explosion due to concurrency is handled by introducing a partial-order representation for systems, and defining system correctness as a simple relation between two partial orders on the same set of system events (a graph problem). State explosion due to nondeterminism (chiefly arbitration) is handled when the system to be verified has a clean, finite recurrence structure. Backwards branching is a further optimization. The heart of this approach is the ability, during model checking, to discover a compact finite presentation of the verified system without prior composition of system components. The fully-implemented POM verification system has polynomial space and time performance on traditional asynchronous-circuit benchmarks that are exponential in space and time for other verification systems. We also sketch the generalization of this approach to handle delay-constrained VLSI systems.

Effect of spin-orbit and on-site Coulomb interactions on the electronic structure and lattice dynamics of uranium monocarbide

NASA Astrophysics Data System (ADS)

Wdowik, U. D.; Piekarz, P.; Legut, D.; Jagło, G.

2016-08-01

Uranium monocarbide, a potential fuel material for the generation IV reactors, is investigated within density functional theory. Its electronic, magnetic, elastic, and phonon properties are analyzed and discussed in terms of spin-orbit interaction and localized versus itinerant behavior of the 5 f electrons. The localization of the 5 f states is tuned by varying the local Coulomb repulsion interaction parameter. We demonstrate that the theoretical electronic structure, elastic constants, phonon dispersions, and their densities of states can reproduce accurately the results of x-ray photoemission and bremsstrahlung isochromat measurements as well as inelastic neutron scattering experiments only when the 5 f states experience the spin-orbit interaction and simultaneously remain partially localized. The partial localization of the 5 f electrons could be represented by a moderate value of the on-site Coulomb interaction parameter of about 2 eV. The results of the present studies indicate that both strong electron correlations and spin-orbit effects are crucial for realistic theoretical description of the ground-state properties of uranium carbide.

Angular Momentum Content of the ρ Meson in Lattice QCD

NASA Astrophysics Data System (ADS)

Glozman, Leonid Ya.; Lang, C. B.; Limmer, Markus

2009-09-01

The variational method allows one to study the mixing of interpolators with different chiral transformation properties in the nonperturbatively determined physical state. It is then possible to define and calculate in a gauge-invariant manner the chiral as well as the partial wave content of the quark-antiquark component of a meson in the infrared, where mass is generated. Using a unitary transformation from the chiral basis to the LJ2S+1 basis one may extract a partial wave content of a meson. We present results for the ground state of the ρ meson using quenched simulations as well as simulations with nf=2 dynamical quarks, all for lattice spacings close to 0.15 fm. We point out that these results indicate a simple S13-wave composition of the ρ meson in the infrared, like in the SU(6) flavor-spin quark model.

Angular momentum content of the rho meson in lattice QCD.

PubMed

Glozman, Leonid Ya; Lang, C B; Limmer, Markus

2009-09-18

The variational method allows one to study the mixing of interpolators with different chiral transformation properties in the nonperturbatively determined physical state. It is then possible to define and calculate in a gauge-invariant manner the chiral as well as the partial wave content of the quark-antiquark component of a meson in the infrared, where mass is generated. Using a unitary transformation from the chiral basis to the ;{2S+1}L_{J} basis one may extract a partial wave content of a meson. We present results for the ground state of the rho meson using quenched simulations as well as simulations with n_{f} = 2 dynamical quarks, all for lattice spacings close to 0.15 fm. We point out that these results indicate a simple ;{3}S_{1}-wave composition of the rho meson in the infrared, like in the SU(6) flavor-spin quark model.

Handling target obscuration through Markov chain observations

NASA Astrophysics Data System (ADS)

Kouritzin, Michael A.; Wu, Biao

2008-04-01

Target Obscuration, including foliage or building obscuration of ground targets and landscape or horizon obscuration of airborne targets, plagues many real world filtering problems. In particular, ground moving target identification Doppler radar, mounted on a surveillance aircraft or unattended airborne vehicle, is used to detect motion consistent with targets of interest. However, these targets try to obscure themselves (at least partially) by, for example, traveling along the edge of a forest or around buildings. This has the effect of creating random blockages in the Doppler radar image that move dynamically and somewhat randomly through this image. Herein, we address tracking problems with target obscuration by building memory into the observations, eschewing the usual corrupted, distorted partial measurement assumptions of filtering in favor of dynamic Markov chain assumptions. In particular, we assume the observations are a Markov chain whose transition probabilities depend upon the signal. The state of the observation Markov chain attempts to depict the current obscuration and the Markov chain dynamics are used to handle the evolution of the partially obscured radar image. Modifications of the classical filtering equations that allow observation memory (in the form of a Markov chain) are given. We use particle filters to estimate the position of the moving targets. Moreover, positive proof-of-concept simulations are included.

Large quantum rings in the ν > 1 quantum Hall regime.

PubMed

Räsänen, E; Aichinger, M

2009-01-14

We study computationally the ground-state properties of large quantum rings in the filling-factor ν>1 quantum Hall regime. We show that the arrangement of electrons into different Landau levels leads to clear signatures in the total energies as a function of the magnetic field. In this context, we discuss possible approximations for the filling factor ν in the system. We are able to characterize integer-ν states in quantum rings in an analogy with conventional quantum Hall droplets. We also find a partially spin-polarized state between ν = 2 and 3. Despite the specific topology of a quantum ring, this state is strikingly reminiscent of the recently found ν = 5/2 state in a quantum dot.

Photoassociation of cold (RbCs)2 tetramers in the ground electronic state

NASA Astrophysics Data System (ADS)

Gacesa, Marko; Côté, Robin

2017-04-01

We theoretically investigate prospects for photoassociative formation of cold (RbCs)2 tetramers from a pair of ultracold RbCs molecules. The long-range region of the potential energy surface (PES) of the lowest electronic state of (RbCs)2 can be affected by orienting both RbCs molecules by an external electric field. In fact, we find a long-range barrier that supports long-range shelf states for relative angles between the dimers' internuclear axes smaller than about 20°. We show that these shelf states can be populated by spontaneous decay from the first excited electronic state which can be efficiently populated by photoassociation from the scattering continuum at ultracold temperatures. The vibrationally excited ground-state tetramer molecules formed this way have sufficiently long lifetimes to allow experimental detection. Moreover, for the relative angles between the dimers close to 20°, the proposed approach may result in production of deeply bound tetramers. Partially supported by the NASA Postdoctoral Program at the NASA Ames Research Center, administered by USRA and the MURI US Army Research Office Grant No. W911NF-14-1-0378 (MG), and by the PIF program of the National Science Foundation Grant No. PHY-141556.

Water resources data, Idaho, 2003; Volume 3. Ground water records

USGS Publications Warehouse

Campbell, A.M.; Conti, S.N.; O'Dell, I.

2003-01-01

Water resources data for the 2003 water year for Idaho consists of records of stage, discharge, and water quality of streams; stage, contents, and water quality of lakes and reservoirs; discharge of irrigation diversions; and water levels and water quality of groundwater. The three volumes of this report contain discharge records for 208 stream-gaging stations and 14 irrigation diversions; stage only records for 6 stream-gaging stations; stage only for 6 lakes and reservoirs; contents only for 13 lakes and reservoirs; water-quality for 50 stream-gaging stations and partial record sites, 3 lakes sites, and 398 groundwater wells; and water levels for 427 observation network wells and 900 special project wells. Additional water data were collected at various sites not involved in the systematic data collection program and are published as miscellaneous measurements. Volumes 1 & 2 contain the surface-water and surface-water-quality records. Volume 3 contains the ground-water and ground-water-quality records. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State and Federal agencies in Idaho, adjacent States, and Canada.

Water resources data, Idaho, 2004; Volume 3. Ground water records

USGS Publications Warehouse

Campbell, A.M.; Conti, S.N.; O'Dell, I.

2005-01-01

Water resources data for the 2004 water year for Idaho consists of records of stage, discharge, and water quality of streams; stage, contents, and water quality of lakes and reservoirs; discharge of irrigation diversions; and water levels and water quality of groundwater. The three volumes of this report contain discharge records for 209 stream-gaging stations and 8 irrigation diversions; stage only records for 6 stream-gaging stations; stage only for 6 lakes and reservoirs; contents only for 13 lakes and reservoirs; water-quality for 39 stream-gaging stations and partial record sites, 18 lakes sites, and 395 groundwater wells; and water levels for 425 observation network wells. Additional water data were collected at various sites not involved in the systematic data collection program and are published as miscellaneous measurements. Volumes 1 & 2 contain the surface-water and surface-water-quality records. Volume 3 contains the ground-water and ground-water-quality records. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State and Federal agencies in Idaho, adjacent States, and Canada.

Full Wave Function Optimization with Quantum Monte Carlo and Its Effect on the Dissociation Energy of FeS.

PubMed

Haghighi Mood, Kaveh; Lüchow, Arne

2017-08-17

Diffusion quantum Monte Carlo calculations with partial and full optimization of the guide function are carried out for the dissociation of the FeS molecule. For the first time, quantum Monte Carlo orbital optimization for transition metal compounds is performed. It is demonstrated that energy optimization of the orbitals of a complete active space wave function in the presence of a Jastrow correlation function is required to obtain agreement with the experimental dissociation energy. Furthermore, it is shown that orbital optimization leads to a 5 Δ ground state, in agreement with experiments but in disagreement with other high-level ab initio wave function calculations which all predict a 5 Σ + ground state. The role of the Jastrow factor in DMC calculations with pseudopotentials is investigated. The results suggest that a large Jastrow factor may improve the DMC accuracy substantially at small additional cost.

β+ decay and cosmic-ray half-life of 91Nb

NASA Astrophysics Data System (ADS)

Hindi, M. M.; Sur, Bhaskar; Wedding, Kristin L.; Bardayan, D. W.; Czerwinski, K. R.; da Cruz, M. T. F.; Hoffman, D. C.; Larimer, R.-M.; Lesko, K. T.; Norman, Eric B.

1993-06-01

In the laboratory, 91Nb decays by electron capture with a 680-yr half-life. However, as a high energy cosmic ray, it would be stripped of its atomic electrons and would be able to undergo only β+ decay. We produced and chemically purified a sample of 91Nb and observed its decay with an array of Ge and NaI detectors. By following the β+ annihilation radiation, we were able to determine the β+ branching ratios of both the 105-keV, 61-d isomer and the ground state of 91Nb. The ground-state branch is (7.7+/-0.8)×10-3% leading to a β+ partial half-like of (8.8+/-1.9)×106 yr. Such a value of the half-life makes 91Nb a good candidate for determining the confinement time of this secondary component of the cosmic rays.

Photodissociation studies of the electronic and vibrational spectroscopy of Ni(+)(H2O).

PubMed

Daluz, Jennifer S; Kocak, Abdulkadir; Metz, Ricardo B

2012-02-09

The electronic spectrum of Ni⁺(H₂O) has been measured from 16200 to 18000 cm⁻¹ using photofragment spectroscopy. Transitions to two excited electronic states are observed; they are sufficiently long-lived that the spectrum is vibrationally and partially rotationally resolved. An extended progression in the metal-ligand stretch is observed, and the absolute vibrational quantum numbering is assigned by comparing isotopic shifts between ⁵⁸Ni⁺(H₂O) and ⁶⁰Ni⁺(H₂O). Time-dependent density functional calculations aid in assigning the spectrum. Two electronic transitions are observed, from the ²A₁ ground state (which correlates to the ²D, 3d⁹ ground state of Ni⁺) to the 3²A₁ and 2²A₂ excited states. These states are nearly degenerate and correlate to the ²F, 3d⁸4s excited state of Ni⁺. Both transitions are quite weak, but surprisingly, the transition to the ²A₂ state is stronger, although it is symmetry-forbidden. The 3d⁸4s states of Ni⁺ interact less strongly with water than does the ground state; therefore, the excited states observed are less tightly bound and have a longer metal-ligand bond than the ground state. Calculations at the CCSD(T)/aug-cc-pVTZ level predict that binding to Ni⁺ increases the H-O-H angle in water from 104.2 to 107.5° as the metal removes electron density from the oxygen lone pairs. The photodissociation spectrum shows well-resolved rotational structure due to rotation about the Ni-O axis. This permits determination of the spin rotation constants ε(αα)'' = -12 cm⁻¹ and ε(αα)' = -3 cm⁻¹ and the excited state rotational constant A' = 14.5 cm⁻¹. This implies a H-O-H angle of 104 ± 1° in the 2²A₂ excited state. The O-H stretching frequencies of the ground state of Ni⁺(H₂O) were measured by combining IR excitation with visible photodissociation in a double resonance experiment. The O-H symmetric stretch is ν₁'' = 3616.5 cm⁻¹; the antisymmetric stretch is ν₅'' = 3688 cm⁻¹. These values are 40 and 68 cm⁻¹ lower, respectively, than those in bare H₂O.

High-resolution threshold photoionization of N2O

NASA Technical Reports Server (NTRS)

Wiedmann, R. T.; Grant, E. R.; Tonkyn, R. G.; White, M. G.

1991-01-01

Pulsed field ionization (PFI) has been used in conjunction with a coherent VUV source to obtain high-resolution threshold photoelectron spectra for the (000), (010), (020), and (100) vibrational states of the N2O(+) cation. Simulations for the rotational profiles of each vibronic level were obtained by fitting the Buckingham-Orr-Sichel equations using accurate spectroscopic constants for the ground states of the neutral and the ion. The relative branch intensities are interpreted in terms of the partial waves of the outgoing photoelectron to which the ionic core is coupled and in terms of the angular momentum transferred to the core.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rosenau, Philip

A wide variety of propagating disturbances in physical systems are described by equations whose solutions lack a sharp propagating front. We demonstrate that presence of particular nonlinearities may induce such fronts. To exemplify this idea, we study both dissipative u{sub t}+{partial_derivative}{sub x}f(u)=u{sub xx} and dispersive u{sub t}+{partial_derivative}{sub x}f(u)+u{sub xxx}=0 patterns, and show that a weakly singular convection f(u)=-u{sup {alpha}}+u{sup m}, 0<{alpha}<1

High-resolution spectroscopy of the C-N stretching band of methylamine

NASA Astrophysics Data System (ADS)

Lees, Ronald M.; Sun, Zhen-Dong; Billinghurst, B. E.

2011-09-01

The C-N stretching infrared fundamental of CH3NH2 has been investigated by high-resolution laser sideband and Fourier transform synchrotron spectroscopy to explore the energy level structure and to look for possible interactions with high-lying torsional levels of the ground state and other vibrational modes. The spectrum is complicated by two coupled large-amplitude motions in the molecule, the CH3 torsion and the NH2 inversion, which lead to rich spectral structure with a wide range of energy level splittings and relative line intensities. Numerous sub-bands have been assigned for K values ranging up to 12 for the stronger a inversion species for the vt = 0 torsional state, along with many of the weaker sub-bands of the s species. The C-N stretching sub-state origins have been determined by fitting the upper-state term values to J(J + 1) power-series expansions. For comparison with the ground-state behaviour, both ground and C-N stretch origins have been fitted to a phenomenological Fourier series model that produces an interesting pattern with the differing periodicities of the torsional and inversion energies. The amplitude of the torsional energy oscillation increases substantially for the C-N stretch, while the amplitude of the inversion energy oscillation is relatively unchanged. Independent inertial scale factors ρ were fitted for the torsion and the inversion and differ significantly in the upper state. The C-N stretching vibrational energy is determined to be 1044.817 cm-1, while the effective upper state B-value is 0.7318 cm-1. Several anharmonic resonances with vt = 4 ground-state levels have been observed and partially characterized. A variety of J-localized level-crossing resonances have also been seen, five of which display forbidden transitions arising from intensity borrowing that allow determination of the interaction coupling constants.

75 FR 33747 - National Oil and Hazardous Substances Pollution Contingency Plan; National Priorities List...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-06-15

... Notice of Intent to Delete the soils of Operable Unit 1 and the underlying ground water of the... preclude future actions under Superfund. This partial deletion pertains to the soils of Operable Unit 1 and... Partial Deletion for the soils of Operable Unit 1 and the underlying ground water of the approximately 8...

Faddeev calculation for ^9_ΛBe hypernucleus

NASA Astrophysics Data System (ADS)

Suslov, Vladimir; Filikhin, Igor; Vlahovic, Branislav

2003-04-01

Faddeev calculations are performed for the ^9_ΛBe hypernucleus in terms of α's and Λ clusters using various Λα potential models. The main goal of our calculations is to estimate higher partial waves contribution in binding energy of ^9_ΛBe ground state (1/2^+) and particularly contribution from the high partial waves of the Λα pair. Phenomenological Ali-Bodmer potential is employed for description of the αα interaction. This potential has s, d and g - waves components. For a Λα potential both form and parameters are uncertain, because Λα interaction data are limited by the experimental value of binding energy of the ^5_ΛHe hypernucleus, which is considered as the bound s-wave state of the Λα system. The binding energy of the ^9_ΛBe is calculated for two different cases. First the s-wave Λα potential acting in all partial waves in the Λα subsystem is used. Second, a recent more realistic Λα potential model including the s and p-partial components from work [1] is employed. We compared these models and discussed validity of the s-wave approximation for calculation of ^9_ΛBe hypernucleus. This work was partially supported by Department of Defenses through the grant No.DAAD 19-01-1-0795. The work of V.M.S and I.N.F was supported by the RFFI under Grant No. 02-02-16562. References: [1] K.S. Myint, S. Shinmura and Y. Akaishi, nucl-th/0209090.

Response of changes in seasonal soil freeze/thaw state to climate change from 1950 to 2010 across china

NASA Astrophysics Data System (ADS)

Peng, Xiaoqing; Frauenfeld, Oliver W.; Cao, Bin; Wang, Kang; Wang, Huijuan; Su, Hang; Huang, Zhe; Yue, Dongxia; Zhang, Tingjun

2016-11-01

Variations in seasonal soil freeze/thaw state are important indicators of climate change and influence ground temperature, hydrological processes, surface energy, and the moisture balance. Previous studies mainly focused on the active layer and permafrost, while seasonally frozen ground research in nonpermafrost regions has received less attention. In this study, we investigate the response of changes in seasonal soil freeze/thaw state to changes in air temperatures by combining observations from more than 800 stations with gridded mean monthly air temperature data across China. The results show that mean annual air temperature (MAAT) increased statistically significantly by 0.29 ± 0.03°C/decade from 1967 to 2013, with greater warming on the Qinghai-Tibetan Plateau. There is a statistically significant decrease in the freeze/thaw cycle (FTC) at 0.39 ± 0.05 cycles/decade. In addition, there are strong negative correlations between FTC and MAAT. Estimating the soil freeze/thaw state classification based on the number of days in the month, we find that changes of mean annual area extent of seasonal soil freeze/thaw state decreased significantly for completely frozen (CF) ground, while the area extent of partially frozen (PF) and unfrozen (UF) ground both increased. Changes in mean monthly area extent of seasonal soil freeze/thaw state indicate that the extent of CF and UF area was decreasing and increasing, respectively. But for the extent of PF areas, both increasing and decreasing trends were observed. Quantifying the spatial pattern of the seasonal soil freeze/thaw, we find that CF and PF areas are located in northern China and the Tibetan Plateau from December to March, and UF areas are located in southern China. The variations of mean annual area extent departure of soil freeze/thaw states are consistent with MAAT changes in different land cover types across China.

Simultaneous measurement of brain tissue oxygen partial pressure, temperature, and global oxygen consumption during hibernation, arousal, and euthermy in non-sedated and non-anesthetized Arctic ground squirrels.

PubMed

Ma, Yilong; Wu, Shufen

2008-09-30

This study reports an online temperature correction method for determining tissue oxygen partial pressure P(tO2) in the striatum and a novel simultaneous measurement of brain P(tO2) and temperature (T(brain)) in conjunction with global oxygen consumption V(O2) in non-sedated and non-anesthetized freely moving Arctic ground squirrels (AGS, Spermophilus parryii). This method fills an important research gap-the lack of a suitable method for physiologic studies of tissue P(O2) in hibernating or other cool-blooded species. P(tO2) in AGS brain during euthermy (21.22+/-2.06 mmHg) is significantly higher (P=0.016) than during hibernation (13.21+/-0.46 mmHg) suggests brain oxygenation in the striatum is normoxic during euthermy and hypoxic during hibernation. These results in P(tO2) are different from blood oxygen partial pressure P(aO2) in AGS, which are significantly lower during euthermy than during hibernation and are actually hypoxic during euthermy and normoxic during hibernation in our previous study. This intriguing difference between the P(O2) of brain tissue and blood during these two physiological states suggests that regional mechanisms in the brain play a role in maintaining tissue oxygenation and protect against hypoxia during hibernation.

Femtosecond stimulated Raman evidence for charge-transfer character in pentacene singlet fission† †Electronic supplementary information (ESI) available: Actinic pump spectrum, discussion on ground state addition process, peak fitting procedure, transient absorption data, power dependence measurements, etalon pulse shaping, TIPS-pentacene FSRS data, and optimized geometry and frequency calculation results. See DOI: 10.1039/c7sc03496b

PubMed Central

Hart, Stephanie M.; Silva, W. Ruchira

2017-01-01

Singlet fission is a spin-allowed process in which an excited singlet state evolves into two triplet states. We use femtosecond stimulated Raman spectroscopy, an ultrafast vibrational technique, to follow the molecular structural evolution during singlet fission in order to determine the mechanism of this process. In crystalline pentacene, we observe the formation of an intermediate characterized by pairs of excited state peaks that are red- and blue-shifted relative to the ground state features. We hypothesize that these features arise from the formation of cationic and anionic species due to partial transfer of electron density from one pentacene molecule to a neighboring molecule. These observations provide experimental evidence for the role of states with significant charge-transfer character which facilitate the singlet fission process in pentacene. Our work both provides new insight into the singlet fission mechanism in pentacene and demonstrates the utility of structurally-sensitive time-resolved spectroscopic techniques in monitoring ultrafast processes. PMID:29675170

Treating Zc(3900 ) and Z (4430 ) as the ground state and first radially excited tetraquarks

NASA Astrophysics Data System (ADS)

Agaev, S. S.; Azizi, K.; Sundu, H.

2017-08-01

Exploration of the resonances Zc(3900 ) and Z (4430 ) are performed by assuming that they are the ground state and first radial excitation of the same tetraquark with JP=1+. The mass and current coupling of the Zc(3900 ) and Z (4430 ) states are calculated using the QCD two-point sum rule method by taking into account vacuum condensates up to eight dimensions. We investigate the vertices ZcMhMl and Z MhMl, with Mh and Ml being the heavy and light mesons and evaluate the strong couplings gZcMhMl and gZ MhMl using the QCD sum rule on the light cone. The extracted couplings allow us to find the partial width of the decays Zc(3900 )→J /ψ π , ψ'π , ηcρ and Z (4430 )→ψ'π , J /ψ π , ηc'ρ , ηcρ , which may help in comprehensive investigation of these resonances. We compare the width of the decays of Zc(3900 ) and Z (4430 ) resonances with available experimental data as well as existing theoretical predictions.

Simulation of scenario earthquake influenced field by using GIS

USGS Publications Warehouse

Zuo, H.-Q.; Xie, L.-L.; Borcherdt, R.D.

1999-01-01

The method for estimating the site effect on ground motion specified by Borcherdt (1994a, 1994b) is briefly introduced in the paper. This method and the detail geological data and site classification data in San Francisco bay area of California, the United States, are applied to simulate the influenced field of scenario earthquake by GIS technology, and the software for simulating has been drawn up. The paper is a partial result of cooperative research project between China Seismological Bureau and US Geological Survey.

Coherence Evolution and Transfer Supplemented by Sender's Initial-State Restoring

NASA Astrophysics Data System (ADS)

Fel'dman, E. B.; Zenchuk, A. I.

2017-12-01

The evolution of quantum coherences comes with a set of conservation laws provided that the Hamiltonian governing this evolution conserves the spin-excitation number. At that, coherences do not intertwist during the evolution. Using the transmission line and the receiver in the initial ground state we can transfer the coherences to the receiver without interaction between them, although the matrix elements contributing to each particular coherence intertwist in the receiver's state. Therefore we propose a tool based on the unitary transformation at the receiver side to untwist these elements and thus restore (at least partially) the structure of the sender's initial density matrix. A communication line with two-qubit sender and receiver is considered as an example of implementation of this technique.

Interactions and low-energy collisions between an alkali ion and an alkali atom of a different nucleus

NASA Astrophysics Data System (ADS)

Rakshit, Arpita; Ghanmi, Chedli; Berriche, Hamid; Deb, Bimalendu

2016-05-01

We study theoretically interaction potentials and low-energy collisions between different alkali atoms and alkali ions. Specifically, we consider systems such as X + {{{Y}}}+, where X({{{Y}}}+) is either Li(Cs+) or Cs(Li+), Na(Cs+) or Cs(Na+) and Li(Rb+) or Rb(Li+). We calculate the molecular potentials of the ground and first two excited states of these three systems using a pseudopotential method and compare our results with those obtained by others. We derive ground-state scattering wave functions and analyze the cold collisional properties of these systems for a wide range of energies. We find that, in order to get convergent results for the total scattering cross sections for energies of the order 1 K, one needs to take into account at least 60 partial waves. The low-energy scattering properties calculated in this paper may serve as a precursor for experimental exploration of quantum collisions between an alkali atom and an alkali ion of a different nucleus.

[beta][sup +] decay and cosmic-ray half-life of [sup 91]Nb

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hindi, M.M.; Sur, B.; Wedding, K.L.

1993-06-01

In the laboratory, [sup 91]Nb decays by electron capture with a 680-yr half-life. However, as a high energy cosmic ray, it would be stripped of its atomic electrons and would be able to undergo only [beta][sup +] decay. We produced and chemically purified a sample of [sup 91]Nb and observed its decay with an array of Ge and NaI detectors. By following the [beta][sup +] annihilation radiation, we were able to determine the [beta][sup +] branching ratios of both the 105-keV, 61-d isomer and the ground state of [sup 91]Nb. The ground-state branch is (7.7[plus minus]0.8)[times]10[sup [minus]3]% leading to amore » [beta][sup +] partial half-like of (8.8[plus minus]1.9)[times]10[sup 6] yr. Such a value of the half-life makes [sup 91]Nb a good candidate for determining the confinement time of this secondary component of the cosmic rays.« less

Water Resources Data, Pennsylvania, Water Year 2001, Volume 2. Susquehanna and Potomac River Basins

USGS Publications Warehouse

Durlin, R.R.; Schaffstall, W.P.

2001-01-01

IntroductionThe Water Resources Division of the U.S. Geological Survey, in cooperation with State, municipal, and Federal agencies, collects a large amount of data pertaining to the water resources of Pennsylvania each water year. These data, accumulated during many water years, constitute a valuable data base for developing an improved understanding of the water resources of the State. To make these data readily available to interested parties outside the Geological Survey, these data are published annually in this report series entitled "Water Resources Data - Pennsylvania, Volumes 1, 2, and 3." Volume 1 contains data for the Delaware River Basin; Volume 2, the Susquehanna and Potomac River Basins; and Volume 3, the Ohio and St. Lawrence River Basins.This report, Volume 2, contains: (1) discharge records for 83 continuous-record streamflow-gaging stations, 15 partial-record stations, and 24 special study and miscellaneous streamflow sites; (2) elevation and contents records for 12 lakes and reservoirs; (3) water-quality records for 9 streamflow gaging stations and 73 partial-record and project stations; and (4) water-level records for 36 ground-water network observation wells and water-quality analyses of ground water from 8 wells; (5) water-quality analyses at 123 special study ground-water wells; and, (6) miscellaneous water-level measurements at 80 special study ground-water wells. Additional water data collected at various sites not involved in the systematic data-collection program may also be presented.Publications similar to this report are published annually by the Geological Survey for all States. For the purpose of archiving, these official reports have an identification number consisting of the two-letter State abbreviation, the last two digits of the water year, and the volume number. For example, this volume is identified as "U.S. Geological Survey Water-Data Report PA-01-2." These water-data reports, beginning with the 1971 water year, are for sale as paper copy or microfiche by the National Technical Information Service, U.S. Department of Commerce, Springfield, VA 22161.The annual series of Water Data Reports for Pennsylvania began with the 1961 water-year report and contained only data relating to quantities of surface water. With the 1964 water year, a companion report (part 2) was introduced that contained only data relating to water quality. Beginning with the 1975 water year the report was changed to three volumes (by river basin), with each volume containing data on quantities of surface water, quality of surface and ground water, and ground-water levels.Prior to the introduction of this series and for several years concurrent with it, water-resources data for Pennsylvania were published in U.S. Geological Survey Water-Supply Papers. Data on stream discharge and stage, and on lake or reservoir contents and stage, through September 1960, were published annually under the title "Surface-Water Supply of the United States," which was released in numbered parts as determined by natural drainage basins. For the 1961-70 water years, these data were published in two 5-year reports. Data prior to 1961 are included in two reports: "Compilation of Records of Surface Waters of the United States through 1950," and "Compilation of Records of Surface Waters of the United States, October 1950 to September 1960." Data for Pennsylvania are published in Parts 1, 3, and 4. Data on chemical quality, temperature, and suspended sediment for the 1941-70 water years were published annually under the title "Quality of Surface Waters of the United States," and ground-water levels for the 1935-74 water years were published annually under the title "Ground-Water Levels in the United States." The above mentioned Water-Supply Papers may be consulted in the libraries of the principal cities of the United States and may be purchased from the U.S. Geological Survey, Information Services, Box 25286, Denver, CO 80225.Information for ordering specific reports may be obtained from the Pennsylvania District Office at the address on the back of the title page or by phoning the Scientific and Technical Products Section at (717) 730-6940. Information on the availability of unpublished data or statistical analyses may be obtained from the District Information Specialist by telephone at (717) 730-6916 or by FAX at (717) 730-6997.

Real-Time Generation of the Footprints both on Floor and Ground

NASA Astrophysics Data System (ADS)

Hirano, Yousuke; Tanaka, Toshimitsu; Sagawa, Yuji

This paper presents a real-time method for generating various footprints in relation to state of walking. In addition, the method is expanded to cover both on hard floor and soft ground. Results of the previous method were not so realistic, because the method places same simple foot prints on the motion path. Our method runs filters on the original pattern of footprint on GPU. And then our method gradates intensity of the pattern to two directions, in order to create partially dark footprints. Here parameters of the filter and the gradation are changed by move speed and direction. The pattern is mapped on a polygon. If the walker is pigeon-toed or bandy-legged, the polygon is rotated inside or outside, respectively. Finally, it is placed on floor. Footprints on soft ground are concavity and convexity caused by walking. Thus an original pattern of footprints on ground is defined as a height map. The height map is modified using the filter and the gradation operation developed for floor footprints. The height map is converted to a bump map to fast display the concavity and convexity of footprints.

THE LIQUEFACTION RISK ANALYSIS OF CEMENT-TREATED SANDY GROUND CONSIDERING THE SPATIAL VARIABILITY OF SOIL STRENGTH

NASA Astrophysics Data System (ADS)

Kataoka, Norio; Kasama, Kiyonobu; Zen, Kouki; Chen, Guangqi

This paper presents a probabilistic method for assessi ng the liquefaction risk of cement-treated ground, which is an anti-liquefaction ground improved by cemen t-mixing. In this study, the liquefaction potential of cement-treated ground is analyzed statistically using Monte Carlo Simulation based on the nonlinear earthquake response analysis consid ering the spatial variability of so il properties. The seismic bearing capacity of partially liquefied ground is analyzed in order to estimat e damage costs induced by partial liquefaction. Finally, the annual li quefaction risk is calcu lated by multiplying the liquefaction potential with the damage costs. The results indicated that the proposed new method enables to evaluate the probability of liquefaction, to estimate the damage costs using the hazard curv e, fragility curve induced by liquefaction, and liq uefaction risk curve.

Implicit memory for novel figure-ground displays includes a history of cross-border competition.

PubMed

Peterson, Mary A; Lampignano, Daniel W

2003-08-01

When configural cues specify that a figure lies on opposite sides of a repeated border in prime andprobe shapes, probe latencies are longer than when prime and probe borders are unrelated. Do such results reflect negative priming for the shape of the prime ground or cross-border competition from figure memory? The present study tested these alternatives by adding partial closure as a competing cue and reducing the similarity between the prime ground and the shape of the probe. Results supported the cross-border competition interpretation. Additional findings were that partial closure is a configural cue and that response effects can emerge from the potential shape on the ground side of a border. One prior experience was sufficient for these effects.

Hybrid joule heating/electro-osmosis process for extracting contaminants from soil layers

DOEpatents

Carrigan, Charles R.; Nitao, John J.

2003-06-10

Joule (ohmic) heating and electro-osmosis are combined in a hybrid process for removal of both water-soluble contaminants and non-aqueous phase liquids from contaminated, low-permeability soil formations that are saturated. Central to this hybrid process is the partial desaturation of the formation or layer using electro-osmosis to remove a portion of the pore fluids by induction of a ground water flow to extraction wells. Joule heating is then performed on a partially desaturated formation. The joule heating and electro-osmosis operations can be carried out simultaneously or sequentially if the desaturation by electro-osmosis occurs initially. Joule heating of the desaturated formation results in a very effective transfer or partitioning of liquid state contaminants to the vapor phase. The heating also substantially increases the vapor phase pressure in the porous formation. As a result, the contaminant laden vapor phase is forced out into soil layers of a higher permeability where other conventional removal processes, such as steam stripping or ground water extraction can be used to capture the contaminants. This hybrid process is more energy efficient than joule heating or steam stripping for cleaning low permeability formations and can share electrodes to minimize facility costs.

Youngest radiocarbon age for Jefferson's ground sloth, Megalonyx jeffersonii (Xenarthra, Megalonychidae)

NASA Astrophysics Data System (ADS)

Gregory McDonald, H.; Stafford, Thomas W.; Gnidovec, Dale M.

2015-03-01

A partial skeleton of the extinct ground sloth, Megalonyx jeffersonii, recovered from a farm near Millersburg, Ohio in 1890, was radiocarbon dated for the first time. The ungual dated is part of a skeleton mounted for exhibit at the Orton Geological Museum at Ohio State University and was the first mounted skeleton of this animal. From its initial discovery the bones were treated with multiple organic compounds that had the potential to compromise the radiocarbon age and the specimen required special treatments in order to obtain a valid radiocarbon age. The 14C measurement on the ungual from this skeleton (11,235 ± 40 14C yr BP = 13,180-13,034 cal yr BP) is the youngest 14C age presently determined for M. jeffersonii.

Information-rich spectral channels for simulated retrievals of partial column-averaged methane

NASA Astrophysics Data System (ADS)

Su, Zhan; Xi, Xi; Natraj, Vijay; Li, King-Fai; Shia, Run-Lie; Miller, Charles E.; Yung, Yuk L.

2016-01-01

Space-based remote sensing of the column-averaged methane dry air mole fraction (XCH4) has greatly increased our understanding of the spatiotemporal patterns in the global methane cycle. The potential to retrieve multiple pieces of vertical profile information would further improve the quantification of CH4 across space-time scales. We conduct information analysis for channel selection and evaluate the prospects of retrieving multiple pieces of information as well as total column CH4 from both ground-based and space-based near-infrared remote sensing spectra. We analyze the degrees of freedom of signal (DOF) in the CH4 absorption bands near 2.3 μm and 1.6 μm and select ˜1% of the channels that contain >95% of the information about the CH4 profile. The DOF is around 4 for fine ground-based spectra (resolution = 0.01 cm-1) and 3 for coarse space-based spectra (resolution = 0.20 cm-1) based on channel selection and a signal-to-noise ratio (SNR) of 300. The DOF varies from 2.2 to 3.2 when SNR is between 100 and 300, and spectral resolution is 0.20 cm-1. Simulated retrieval tests in clear-sky conditions using the selected channels reveal that the retrieved partial column-averaged CH4 values are not sensitive to the a priori profiles and can reflect local enhancements of CH4 in different partial air columns. Both the total and partial column-averaged retrieval errors in all tests are within 1% of the true state. These simulated tests highlight the possibility to retrieve up to three to four pieces of information about the vertical distribution of CH4 in reality.

Molecular Prerequisites for Diminished Cold Sensitivity in Ground Squirrels and Hamsters.

PubMed

Matos-Cruz, Vanessa; Schneider, Eve R; Mastrotto, Marco; Merriman, Dana K; Bagriantsev, Sviatoslav N; Gracheva, Elena O

2017-12-19

Thirteen-lined ground squirrels and Syrian hamsters are known for their ability to withstand cold during hibernation. We found that hibernators exhibit cold tolerance even in the active state. Imaging and electrophysiology of squirrel somatosensory neurons reveal a decrease in cold sensitivity of TRPM8-expressing cells. Characterization of squirrel and hamster TRPM8 showed that the channels are chemically activated but exhibit poor activation by cold. Cold sensitivity can be re-introduced into squirrel and hamster TRPM8 by transferring the transmembrane domain from the cold sensitive rat ortholog. The same can be achieved in squirrel TRPM8 by mutating only six amino acids. Reciprocal mutations suppress cold sensitivity of the rat ortholog, supporting functional significance of these residues. Our results suggest that ground squirrels and hamsters exhibit reduced cold sensitivity, partially due to modifications in the transmembrane domain of TRPM8. Our study reveals molecular adaptations that accompany cold tolerance in two species of mammalian hibernators. Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.

Charge Transfer in Collisions of S^4+ with H.

NASA Astrophysics Data System (ADS)

Stancil, P. C.; Turner, A. R.; Cooper, D. L.; Schultz, D. R.; Rakovic, M. J.; Fritsch, W.; Zygelman, B.

2001-05-01

Charge transfer processes due to collisions of ground state S^4+ ions with atomic hydrogen were investigated for energies between 1 meV/u and 10 MeV/u using the quantum-mechanical molecular-orbital close-coupling (MOCC), atomic-orbital close-coupling, classical trajectory Monte Carlo (CTMC), and continuum distorted wave methods. The MOCC calculations utilized ab initio adiabatic potentials and nonadiabatic radial coupling matrix elements obtained with the spin-coupled valence-bond approach. A number of variants of the CTMC approach were explored, including different momentum and radial distributions for the initial state, as well as effective charge and quantum-defect models to determine the corresponding quantum state after capture into final partially-stripped S^3+ excited classical states. Hydrogen target isotope effects were explored and rate coefficients for temperatures between 100 and 10^6 K will be presented

Molecular and structural characterization of New Red and Erythrosine by fluorescence polarization spectroscopy

NASA Astrophysics Data System (ADS)

Zhu, Chun; Du, Jia-Meng; Zhao, Jin-Chen; Zhu, Tuo; Chen, Guo-Qing

2017-07-01

The fundamental and the fluorescence anisotropies of New Red and Erythrosine were measured. The intersection angles between the absorption and the emission dipole moments for New Red and Erythrosine are 4.44∘ and 23.26∘, respectively. The average angle shift of the emission dipole moment of New Red is 3.91∘ during the lifetime of the excited state. This indicates that it has a bifurcated linear structure with weak rotational capacity. The average angle shift of the emission dipole moment of Erythrosine is 9.25∘, indicating that it has a partial planar structure and is easier to rotate. The spatial ground state structures were simulated with Gaussian 09.

Femtosecond stimulated Raman evidence for charge-transfer character in pentacene singlet fission.

PubMed

Hart, Stephanie M; Silva, W Ruchira; Frontiera, Renee R

2018-02-07

Singlet fission is a spin-allowed process in which an excited singlet state evolves into two triplet states. We use femtosecond stimulated Raman spectroscopy, an ultrafast vibrational technique, to follow the molecular structural evolution during singlet fission in order to determine the mechanism of this process. In crystalline pentacene, we observe the formation of an intermediate characterized by pairs of excited state peaks that are red- and blue-shifted relative to the ground state features. We hypothesize that these features arise from the formation of cationic and anionic species due to partial transfer of electron density from one pentacene molecule to a neighboring molecule. These observations provide experimental evidence for the role of states with significant charge-transfer character which facilitate the singlet fission process in pentacene. Our work both provides new insight into the singlet fission mechanism in pentacene and demonstrates the utility of structurally-sensitive time-resolved spectroscopic techniques in monitoring ultrafast processes.

Geology and ground-water resources of North Dakota, with a discussion of the chemical character of the water

USGS Publications Warehouse

Simpson, Howard E.; Riffenburg, Harry Buchholz

1929-01-01

Water is the most valuable of the mineral resources. The study of ground waters is therefore clearly within the field of economic geology and constitutes an important part of the work of the geological surveys, both State and national, as defined by law. In the spring of 1911 the investigation of the ground waters of North Dakota was begun by the North Dakota Geological Survey, and the work was assigned to the author of this paper. During each of the three summers 1911, 1912, and 1913 several weeks were devoted by the author to the field work of a general survey. A report on the ground waters of the State was then prepared by him and was transmitted by the director of the North Dakota Geological Survey to the State printing commission for publication. However, owing to lack of available funds the report was not published.A portion of the summer of 1914 was given to a study of artesian conditions in the Souris River Basin. Since that time considerable work has been done in connection with detailed surveys made for a number of cities and villages in an effort to obtain the best available supply of water for public use.During the summer of 1920 arrangements were made by the United States Geological Survey with the North Dakota Geological Survey whereby the author completed the work as fully as possible by correspondence and brought the report up to date.In the spring of 1921 samples of water from 196 sources were collected by the author and J. H. Buchanan and were sent to the United States Geological Survey for analysis. Most of these samples were analyzed by H. B. Riffenburg, who has used the analyses for a description of the chemical character of ground waters in the State. In addition to the analyses of samples collected in connection with the preparation of this report, over 700 partial analyses from different sources were examined. These analyses are not given in this paper, because the location of many of the wells was not stated definitely, and most of the analyses were incomplete. They were useful, however, in confirming the conclusions based on the analyses that are printed, particularly for counties where only a few samples were collected for this report.

Topological order following a quantum quench

NASA Astrophysics Data System (ADS)

Tsomokos, Dimitris I.; Hamma, Alioscia; Zhang, Wen; Haas, Stephan; Fazio, Rosario

2009-12-01

We determine the conditions under which topological order survives a rapid quantum quench. Specifically, we consider the case where a quantum spin system is prepared in the ground state of the toric code model and, after the quench, it evolves with a Hamiltonian that does not support topological order. We provide analytical results supported by numerical evidence for a variety of quench Hamiltonians. The robustness of topological order under nonequilibrium situations is tested by studying the topological entropy and a dynamical measure, which makes use of the similarity between partial density matrices obtained from different topological sectors.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chasteler, R.M.; Nitschke, J.M.; Firestone, R.B.

Neutron-rich rare-earth isotopes were produced in multinucleon transfer reactions between {sup 170}Er ions and {sup nat}W targets. On-line mass separation was used together with {beta}- and {gamma}-ray spectroscopy in these studies. At mass {ital A}=169, the heaviest known dysprosium isotope, 39(8) s,{sup 169}Dy, was identified. It was observed to {beta}{sup {minus}} decay to the ground state of {sup 169}Ho or through a level at 1578 keV. In the {ital A}=171 mass chain, a partial decay scheme for 55(3)-s {sup 171}Ho was determined.

Grounded theory in music therapy research.

PubMed

O'Callaghan, Clare

2012-01-01

Grounded theory is one of the most common methodologies used in constructivist (qualitative) music therapy research. Researchers use the term "grounded theory" when denoting varying research designs and theoretical outcomes. This may be challenging for novice researchers when considering whether grounded theory is appropriate for their research phenomena. This paper examines grounded theory within music therapy research. Grounded theory is briefly described, including some of its "contested" ideas. A literature search was conducted using the descriptor "music therapy and grounded theory" in Pubmed, CINAHL PsychlNFO, SCOPUS, ERIC (CSA), Web of Science databases, and a music therapy monograph series. A descriptive analysis was performed on the uncovered studies to examine researched phenomena, grounded theory methods used, and how findings were presented, Thirty music therapy research projects were found in refereed journals and monographs from 1993 to "in press." The Strauss and Corbin approach to grounded theory dominates the field. Descriptors to signify grounded theory components in the studies greatly varied. Researchers have used partial or complete grounded theory methods to examine clients', family members', staff, music therapy "overhearers," music therapists', and students' experiences, as well as music therapy creative products and professional views, issues, and literature. Seven grounded theories were offered. It is suggested that grounded theory researchers clarify what and who inspired their design, why partial grounded theory methods were used (when relevant), and their ontology. By elucidating assumptions underpinning the data collection, analysis, and findings' contribution, researchers will continue to improve music therapy research using grounded theory methods.

Water resources data, Pennsylvania, water year 2000. Volume 2. Susquehanna and Potomac River Basins

USGS Publications Warehouse

Durlin, R.R.; Schaffstall, W.P.

2000-01-01

IntroductionThe Water Resources Division of the U.S. Geological Survey, in cooperation with State, municipal, and Federal agencies, collects a large amount of data pertaining to the water resources of Pennsylvania each water year. These data, accumulated during many water years, constitute a valuable data base for developing an improved understanding of the water resources of the State. To make these data readily available to interested parties outside the Geological Survey, these data are published annually in this report series entitled "Water Resources Data - Pennsylvania, Volumes 1, 2, and 3." Volume 1 contains data for the Delaware River Basin; Volume 2, the Susquehanna and Potomac River Basins; and Volume 3, the Ohio and St. Lawrence River Basins.This report, Volume 2, contains: (1) discharge records for 83 continuous-record streamflow-gaging stations, 16 partial-record stations, and 24 special study and miscellaneous streamflow sites; (2) elevation and contents records for 12 lakes and reservoirs; (3) water-quality records for 11 streamflow gaging stations and 70 partial-record and project stations; and (4) water-level records for 30 ground-water network observation wells and water-quality analyses of ground water from 8 wells; and (5) water-quality analyses at 60 special study ground-water wells. Additional water data collected at various sites not involved in the systematic data-collection program may also be presented.Publications similar to this report are published annually by the Geological Survey for all States. For the purpose of archiving, these official reports have an identification number consisting of the two-letter State abbreviation, the last two digits of the water year, and the volume number. For example, this volume is identified as "U.S. Geological Survey Water-Data Report PA-00-2." These water-data reports, beginning with the 1971 water year, are for sale as paper copy or microfiche by the National Technical Information Service, U.S. Department of Commerce, Springfield, VA 22161.The annual series of Water Data Reports for Pennsylvania began with the 1961 water-year report and contained only data relating to quantities of surface water. With the 1964 water year, a companion report (part 2) was introduced that contained only data relating to water quality. Beginning with the 1975 water year the report was changed to three volumes (by river basin), with each volume containing data on quantities of surface water, quality of surface and ground water, and ground-water levels.Prior to the introduction of this series and for several years concurrent with it, water-resources data for Pennsylvania were published in U.S. Geological Survey Water-Supply Papers. Data on stream discharge and stage, and on lake or reservoir contents and stage, through September 1960, were published annually under the title "Surface-Water Supply of the United States," which was released in numbered parts as determined by natural drainage basins. For the 1961-70 water years, these data were published in two 5-year reports. Data prior to 1961 are included in two reports: "Compilation of Records of Surface Waters of the United States through 1950," and "Compilation of Records of Surface Waters of the United States, October 1950 to September 1960." Data for Pennsylvania are published in Parts 1, 3, and 4. Data on chemical quality, temperature, and suspended sediment for the 1941-70 water years were published annually under the title "Quality of Surface Waters of the United States," and ground-water levels for the 1935-74 water years were published annually under the title "Ground-Water Levels in the United States." The above mentioned Water-Supply Papers may be consulted in the libraries of the principal cities of the United States and may be purchased from the U.S. Geological Survey, Information Services, Box 25286, Denver, CO 80225.Information for ordering specific reports may be obtained from the Pennsylvania District Office at the address on the back of the title page or by phoning the Scientific and Technical Products Section at (717) 730-6940. Information on the availability of unpublished data or statistical analyses may be obtained from the District Information Specialist by telephone at (717) 730-6916 or by FAX at (717) 730-6997.

Water Resources Data, Pennsylvania, Water Year 1999. Volume 2. Susquehanna and Potomac River Basins

USGS Publications Warehouse

Durlin, R.R.; Schaffstall, W.P.

2000-01-01

IntroductionThe Water Resources Division of the U.S. Geological Survey, in cooperation with State, municipal, and Federal agencies, collects a large amount of data pertaining to the water resources of Pennsylvania each water year. These data, accumulated during many water years, constitute a valuable data base for developing an improved understanding of the water resources of the State. To make these data readily available to interested parties outside the Geological Survey, these data are published annually in this report series entitled "Water Resources Data - Pennsylvania, Volumes 1, 2, and 3." Volume 1 contains data for the Delaware River Basin; Volume 2, the Susquehanna and Potomac River Basins; and Volume 3, the Ohio River and St. Lawrence River Basins.This report, Volume 2, contains: (1) discharge records for 83 continuous-record streamflow-gaging stations, 16 partial-record stations, and 24 special study and miscellaneous streamflow sites; (2) elevation and contents records for 12 lakes and reservoirs; (3) water-quality records for 11 streamflow gaging stations and 45 partial-record and project stations; and (4) water-level records for 30 ground-water network observation wells and water-quality analyses of ground water from 8 wells; and (5) water-quality analyses at 44 special study ground-water wells. Additional water data collected at various sites not involved in the systematic data-collection program may also be presented. Publications similar to this report are published annually by the Geological Survey for all States. For the purpose of archiving, these official reports have an identification number consisting of the two-letter State abbreviation, the last two digits of the water year, and the volume number. For example, this volume is identified as "U.S. Geological Survey Water-Data Report PA-99-2." These water-data reports, beginning with the 1971 water year, are for sale as paper copy or microfiche by the National Technical Information Service, U.S. Department of Commerce, Springfield, VA 22161.The annual series of Water Data Reports for Pennsylvania began with the 1961 water-year report and contained only data relating to quantities of surface water. With the 1964 water year, a companion report (part 2) was introduced that contained only data relating to water quality. Beginning with the 1975 water year the report was changed to three volumes (by river basin), with each volume containing data on quantities of surface water, quality of surface and ground water, and ground-water levels.Prior to the introduction of this series and for several years concurrent with it, water-resources data for Pennsylvania were published in U.S. Geological Survey Water-Supply Papers. Data on stream discharge and stage, and on lake or reservoir contents and stage, through September 1960, were published annually under the title "Surface-Water Supply of the United States," which was released in numbered parts as determined by natural drainage basins. For the 1961-70 water years, these data were published in two 5-year reports. Data prior to 1961 are included in two reports: "Compilation of Records of Surface Waters of the United States through 1950," and "Compilation of Records of Surface Waters of the United States, October 1950 to September 1960." Data for Pennsylvania are published in Parts 1, 3, and 4. Data on chemical quality, temperature, and suspended sediment for the 1941-70 water years were published annually under the title "Quality of Surface Waters of the United States," and ground-water levels for the 1935-74 water years were published annually under the title "Ground-Water Levels in the United States." The above mentioned Water-Supply Papers may be consulted in the libraries of the principal cities of the United States and may be purchased from the U.S. Geological Survey, Information Services, Box 25286, Denver, CO 80225.Information for ordering specific reports may be obtained from the Pennsylvania District Office at the address on the back of the title page or by phoning the Scientific and Technical Products Section at (717) 730-6940. Information on the availability of unpublished data or statistical analyses may be obtained from the District Information Specialist (telephone (717) 730-6916) or FAX (717) 730-6997.

Recoilless Nuclear Resonance Absorption of Gamma Radiation

NASA Astrophysics Data System (ADS)

Mössbauer, Rudolf L.

It is a high distinction to be permitted to address you on the subject of recoilless nuclear resonance absorption of gamma radiation. The methods used in this special branch of experimental physics have recently found acceptance in many areas of science. I take the liberty to confine myself essentially to the work which I was able to carry out in the years 1955-1958 at the Max Planck Institute in Heidelberg, and which finally led to establishment of the field of recoilless nuclear resonance absorption. Many investigators shared in the preparations of the basis for the research we are concerned with in this lecture. As early as the middle of the last century Stokes observed, in the case of fluorite, the phenomenon now known as fluorescence - namely, that solids, liquids, and gases under certain conditions partially absorb incident electromagnetic radiation which immediately is reradiated. A special case is the so-called resonance fluorescence, a phenomenon in which the re-emitted and the incident radiation both are of the same wavelength. The resonance fluorescence of the yellow D lines of sodium in sodium vapour is a particularly notable and exhaustively studied example. In this optical type of resonance fluorescence, light sources are used in which the atoms undergo transitions from excited states to their ground states (Fig. 1.1). The light quanta emitted in these transitions (A → B) are used to initiate the inverse process of resonance absorption in the atoms of an absorber which are identical with the radiating atoms. The atoms of the absorber undergo a transition here from the ground state (B) to the excited state (A), from which they again return to the ground state, after a certain time delay, by emission of fluorescent light.

Summary appraisals of the Nation's ground-water resources; Lower Colorado region

USGS Publications Warehouse

Davidson, E.S.

1979-01-01

The potential for greater development of ground water in the southwestern part of the region is constrained by land subsidence, earth cracks, increasing costs of pumping and transportation, and moderate to poor chemical quality of water. More ground water can be developed in the northeastern part of the region, where the major constraint is pumping cost owing to low to moderate well yields and depth to water. Some benefits can be realized everywhere in the region through changes in current use and greater efficiencies of use. Additional supplies may be made available by capture of natural evapotranspiration. Increasing the efficiency of use is possible hydrologically but, in the near term, is more expensive than increasing groundwater development. Decrease of irrigation, change to water-saving methods of irrigation, use of saline water, decrease of per capita public- supply use, and more reuse of water in almost every type of use could help extend the supply and thereby reduce the current rate of ground-water depletion. Financial problems have not yet caused an overall decrease in pumpage, but, locally, operating costs or partial dewatering of the aquifer has eliminated or decreased withdrawal. Current water laws in all States of the region, except Arizona, control or allocate the use of ground water.

Electron capture in collisions of S4+ with atomic hydrogen

NASA Astrophysics Data System (ADS)

Stancil, P. C.; Turner, A. R.; Cooper, D. L.; Schultz, D. R.; Rakovic, M. J.; Fritsch, W.; Zygelman, B.

2001-06-01

Charge transfer processes due to collisions of ground state S4+(3s2 1S) ions with atomic hydrogen are investigated for energies between 1 meV u-1 and 10 MeV u-1 using the quantum mechanical molecular-orbital close-coupling (MOCC), atomic-orbital close-coupling, classical trajectory Monte Carlo (CTMC) and continuum distorted wave methods. The MOCC calculations utilize ab initio adiabatic potentials and nonadiabatic radial coupling matrix elements obtained with the spin-coupled valence-bond approach. A number of variants of the CTMC approach were explored, including different momentum and radial distributions for the initial state, as well as effective charge and quantum-defect models to determine the corresponding quantum state after capture into final partially stripped S3+ excited classical states. Hydrogen target isotope effects are explored and rate coefficients for temperatures between 100 and 106 K are also presented.

Laser-induced fluorescence studies of excited Sr reactions: II. Sr(3P1)+CH3F, C2H5F, C2H4F2

NASA Astrophysics Data System (ADS)

Teule, J. M.; Janssen, M. H. M.; Bulthuis, J.; Stolte, S.

1999-06-01

The vibrational and rotational energy distributions of ground state SrF(X 2Σ) formed in the reactions of electronically excited Sr(3P1) with methylfluoride, ethylfluoride, and 1,1-difluoroethane have been studied by laser-induced fluorescence. Although the reactions of ground state Sr with these reactants are exothermic, no SrF products are observed for those reactions in this study. The fraction of available energy disposed into the sum of rotational and vibrational energy of the SrF(X 2Σ) product is approximately the same for all three reactions, i.e., 40%. The reaction of Sr(3P1) with CH3F results in very low vibrational excitation in the SrF reaction product. The product vibration increases in going to C2H5F and C2H4F2. It is concluded that the alkyl group influences the energy disposal mechanism in these reactions, and some suggestions are given for a partial explanation of the observations.

Dipolar order by disorder in the classical Heisenberg antiferromagnet on the kagome lattice

NASA Astrophysics Data System (ADS)

Chern, Gia-Wei

2014-03-01

The first experiments on the ``kagome bilayer'' SCGO triggered a wave of interest in kagome antiferromagnets in particular, and frustrated systems in general. A cluster of early seminal theoretical papers established kagome magnets as model systems for novel ordering phenomena, discussing in particular spin liquidity, partial order, disorder-free glassiness and order by disorder. Despite significant recent progress in understanding the ground state for the quantum S = 1 / 2 model, the nature of the low-temperature phase for the classical kagome Heisenberg antiferromagnet has remained a mystery: the non-linear nature of the fluctuations around the exponentially numerous harmonically degenerate ground states has not permitted a controlled theory, while its complex energy landscape has precluded numerical simulations at low temperature. Here we present an efficient Monte Carlo algorithm which removes the latter obstacle. Our simulations detect a low-temperature regime in which correlations saturate at a remarkably small value. Feeding these results into an effective model and analyzing the results in the framework of an appropriate field theory implies the presence of long-range dipolar spin order with a tripled unit cell.

Common ground for biodiversity and ecosystem services: the “partial protection” challenge

PubMed Central

Faith, Daniel P

2012-01-01

New global initiatives require clarity about similarities and differences between biodiversity and ecosystem services. One argument is that ecosystem services capture utilitarian values, while biodiversity captures intrinsic values. However, the concept of biodiversity equally emerges from anthropogenic use values. Measures of biodiversity indicate broad option values, and so provide different information about future uses and benefits. Such differences nevertheless can be the basis for “common ground” for biodiversity and ecosystem services. Systematic conservation planning and related frameworks acknowledge such differences through effective trade-offs and synergies among different values of society. The early work on regional biodiversity trade-offs includes a little-explored aspect that could enhance this common ground. Regional planning here takes into account the “partial protection” of biodiversity provided by some land uses. Common-ground will be promoted by better integrating the ecosystem services and biodiversity conservation offered by ecosystems at the “natural end of the spectrum” with the partial protection and other benefits/services provided by more intensively-transformed places. PMID:24358821

Evaluation of prompt gamma-ray data and nuclear structure of niobium-94 with statistical model calculations

NASA Astrophysics Data System (ADS)

Turkoglu, Danyal

Precise knowledge of prompt gamma-ray intensities following neutron capture is critical for elemental and isotopic analyses, homeland security, modeling nuclear reactors, etc. A recently-developed database of prompt gamma-ray production cross sections and nuclear structure information in the form of a decay scheme, called the Evaluated Gamma-ray Activation File (EGAF), is under revision. Statistical model calculations are useful for checking the consistency of the decay scheme, providing insight on its completeness and accuracy. Furthermore, these statistical model calculations are necessary to estimate the contribution of continuum gamma-rays, which cannot be experimentally resolved due to the high density of excited states in medium- and heavy-mass nuclei. Decay-scheme improvements in EGAF lead to improvements to other databases (Evaluated Nuclear Structure Data File, Reference Input Parameter Library) that are ultimately used in nuclear-reaction models to generate the Evaluated Nuclear Data File (ENDF). Gamma-ray transitions following neutron capture in 93Nb have been studied at the cold-neutron beam facility at the Budapest Research Reactor. Measurements have been performed using a coaxial HPGe detector with Compton suppression. Partial gamma-ray production capture cross sections at a neutron velocity of 2200 m/s have been deduced relative to that of the 255.9-keV transition after cold-neutron capture by 93Nb. With the measurement of a niobium chloride target, this partial cross section was internally standardized to the cross section for the 1951-keV transition after cold-neutron capture by 35Cl. The resulting (0.1377 +/- 0.0018) barn (b) partial cross section produced a calibration factor that was 23% lower than previously measured for the EGAF database. The thermal-neutron cross sections were deduced for the 93Nb(n,gamma ) 94mNb and 93Nb(n,gamma) 94gNb reactions by summing the experimentally-measured partial gamma-ray production cross sections associated with the ground-state transitions below the 396-keV level and combining that summation with the contribution to the ground state from the quasi-continuum above 396 keV, determined with Monte Carlo statistical model calculations using the DICEBOX computer code. These values, sigmam and sigma 0, were (0.83 +/- 0.05) b and (1.16 +/- 0.11) b, respectively, and found to be in agreement with literature values. Comparison of the modeled population and experimental depopulation of individual levels confirmed tentative spin assignments and suggested changes where imbalances existed.

Theory of inhomogeneous quantum systems. III. Variational wave functions for Fermi fluids

NASA Astrophysics Data System (ADS)

Krotscheck, E.

1985-04-01

We develop a general variational theory for inhomogeneous Fermi systems such as the electron gas in a metal surface, the surface of liquid 3He, or simple models of heavy nuclei. The ground-state wave function is expressed in terms of two-body correlations, a one-body attenuation factor, and a model-system Slater determinant. Massive partial summations of cluster expansions are performed by means of Born-Green-Yvon and hypernetted-chain techniques. An optimal single-particle basis is generated by a generalized Hartree-Fock equation in which the two-body correlations screen the bare interparticle interaction. The optimization of the pair correlations leads to a state-averaged random-phase-approximation equation and a strictly microscopic determination of the particle-hole interaction.

Nuclear magnetic resonance studies of pseudospin fluctuations in URu 2 Si 2

DOE PAGES

Shirer, K. R.; Haraldsen, J. T.; Dioguardi, A. P.; ...

2013-09-26

Here, we report 29Si nuclear magnetic resonance measurements in single crystals and aligned powders of URu 2Si 2 in the hidden order and paramagnetic phases. The spin-lattice relaxation data reveal evidence of pseudospin fluctuations of U moments in the paramagnetic phase. We find evidence for partial suppression of the density of states below 30 K and analyze the data in terms of a two-component spin-fermion model. We propose that this behavior is a realization of a pseudogap between the hidden-order transition T HO and 30 K. This behavior is then compared to other materials that demonstrate precursor fluctuations in amore » pseudogap regime above a ground state with long-range order.« less

Nuclear Data Matters - The obvious case of a bad mixing ratio for 58Co

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hoffman, R. D.; Nesaraja, Caroline D.; Mattoon, Caleb

We present results of modeled cross sections for neutron- and proton-induced reactions leading to the final product nucleus 58Co. In each case the gamma-cascade branching ratios given in the ENSDF database circa 2014 predict modeled nuclear cross sections leading to the ground and first excited metastable state that are incompatible with measured cross sections found in the NNDC experimental cross section database EXFOR. We show that exploring the uncertainty in the mixing ratio used to calculate the gamma-cascade branching ratios for the 53.15 keV 2 nd excited state leads to changes in the predicted partial cross sections by amounts thatmore » give good agreement with measured data.« less

Rovibrationally-Resolved Direct Photodissociation Through The Lyman And Werner Transitions Of H_{2}

NASA Astrophysics Data System (ADS)

Gay, Christopher; Stancil, P. C.

2008-03-01

Direct photodissociation cross sections have been obtained for the Lyman and Werner transitions of H2 using a combination of ab initio and experimentally derived potential curves and dipole transition moments. The partial cross sections have been evaluated for transitions from all 301 rovibrational levels (v'',J'') of the ground electronic state and over a wavelength range that extends from 10nm to the dissociation threshold for each particular rovibrational state. For UV-irradiated molecular gas with column densities of 1016-1019cm-2, direct photodissociation can compete with the Solomon process as an H2 destruction process. This research was supported by NASA grant NNG06GJ11G from the Astrophysics Theory Program.

Short communication: Partial replacement of ground corn with algae meal in a dairy cow diet: Milk yield and composition, nutrient digestibility, and metabolic profile.

PubMed

da Silva, G G; Ferreira de Jesus, E; Takiya, C S; Del Valle, T A; da Silva, T H; Vendramini, T H A; Yu, Esther J; Rennó, F P

2016-11-01

This study was undertaken to evaluate the effects of partially replacing dietary ground corn with a microalgae meal from Prototheca moriformis (composed of deoiled microalgae and soyhulls) on milk yield and composition, nutrient intake, total-tract apparent digestibility, and blood profile of lactating dairy cows. Twenty multiparous Holstein cows (57.7±49.4d in milk, 25.3±5.3 of milk yield, and 590±71kg of live weight at the start of experiment, mean ± standard deviation) were used in a cross-over design experiment, with 21-d periods. Diets were no microalgae meal (CON) or 91.8g/kg of microalgae meal partially replacing dietary ground corn (ALG). Cows showed similar milk yield and composition. The 3.5% fat-corrected milk production was 30.2±1.34kg/d for CON and 31.1±1.42kg/d for ALG. Despite cows having similar dry matter intake, ALG increased neutral detergent fiber and ether extract intake. In addition, cows fed ALG exhibited higher ether extract digestibility. No differences were detected in glucose, urea, amino-aspartate transferase, and gamma-glutamyl transferase blood concentrations. Feeding ALG increased the total cholesterol and high-density lipoprotein in blood compared with CON. The microalgae meal may partially replace ground corn in diets of lactating cows without impairing the animal's performance. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

High-field magnetoconductance in La-Sr manganites of FM and AFM ground states

NASA Astrophysics Data System (ADS)

Jirák, Zdeněk; Kaman, Ondřej; Knížek, Karel; Levinský, Petr; Míšek, Martin; Veverka, Pavel; Hejtmánek, Jiří

2018-06-01

Large-grain La1-xSrxMnO3 ceramic samples of compositions x = 0.45 and 0.55, representing the ferromagnetic (FM) and A-type antiferromagnetic (AFM) ground states, were produced via classical sintering at 1500 °C of cold-pressed sol-gel prepared single-phase nanoparticles. Using the same precursors, nanogranular forms of both manganite ceramics were prepared by fast spark plasma sintering at low temperature of 900 °C, which limits the growth of crystal grains. The magnetotransport of both the bulk and nanogranular forms was investigated in a broad range of magnetic fields up to 130 kOe and analyzed on the basis of detailed magnetic measurements. Both the large-grain and nanogranular systems with x = 0.45, possessing a pure FM state with similar Curie tempereature TC ≈ 345 K), show nearly the same conductivity enhancement in external fields when expressed relatively to the zero-field values. This positive magnetoconductance (MC) can be separated into two terms: (i) the hysteretic low-field MC that reflects the field-induced orientation of magnetic moments of individual grains, and (ii) the high-field MC that depends linearly on external field. In the case of large-grain ceramics with x = 0.55, a partially ordered FM state formed below TC = 264 K is replaced by pure A-type AFM ground state below 204 K. This A-type AFM state is characterized by positive magnetoconductance that is essentially of quadratic dependence on external field in the investigated range up to 130 kOe. On contrary, the nanogranular product with x = 0.55 exhibits a mixed FM/AFM state at low temperatures, and, as a consequence, its magnetotransport combines the features of FM and A-type AFM systems, in which the quadratic term is much enhanced and clearly dominates at high fields. For interpretation of observed behaviors, the theory of grain-boundary tunneling is revisited.

Neutron single-particle strengths at N =40 , 42: Neutron knockout from Ni,7068 ground and isomeric states

NASA Astrophysics Data System (ADS)

Recchia, F.; Weisshaar, D.; Gade, A.; Tostevin, J. A.; Janssens, R. V. F.; Albers, M.; Bader, V. M.; Baugher, T.; Bazin, D.; Berryman, J. S.; Brown, B. A.; Campbell, C. M.; Carpenter, M. P.; Chen, J.; Chiara, C. J.; Crawford, H. L.; Hoffman, C. R.; Kondev, F. G.; Korichi, A.; Langer, C.; Lauritsen, T.; Liddick, S. N.; Lunderberg, E.; Noji, S.; Prokop, C.; Stroberg, S. R.; Suchyta, S.; Wimmer, K.; Zhu, S.

2016-11-01

The distribution of single-particle strength in Ni,6967 was characterized with one-neutron knockout reactions from intermediate-energy Ni,7068 secondary beams, selectively populating neutron-hole configurations at N =39 and 41, respectively. The spectroscopic strengths deduced from the measured partial cross sections to the individual final states, as tagged by their γ -ray decays, are used to identify and quantify neutron configurations in the wave functions. While 69Ni compares well with shell-model predictions, the results for 67Ni challenge the validity of current effective shell-model Hamiltonians by revealing discrepancies that cannot be explained so far. These results suggest that our understanding of the low-lying states in the neutron-rich, semimagic Ni isotopes may be incomplete and requires further investigation on both the experimental and theoretical sides.

Effects of ground-water chemistry and flow on quality of drainflow in the western San Joaquin Valley, California

USGS Publications Warehouse

Fio, John L.; Leighton, David A.

1994-01-01

Chemical and geohydrologic data were used to assess the effects of regional ground-water flow on the quality of on-farm drainflows in a part of the western San Joaquin Valley, California. Shallow ground water beneath farm fields has been enriched in stable isotopes and salts by partial evaporation from the shallow water table and is being displaced by irrigation, drainage, and regional ground-water flow. Ground-water flow is primarily downward in the study area but can flow upward in some down- slope areas. Transitional areas exist between the downward and upward flow zones, where ground water can move substantial horizontal distances (0.3 to 3.6 kilometers) and can require 10 to 90 years to reach the downslope drainage systems. Simulation of ground-water flow to drainage systems indicates that regional ground water contributes to about 11 percent of annual drainflow. Selenium concentrations in ground water and drainwater are affected by geologic source materials, partial evaporation from a shallow water table, drainage-system, and regional ground-water flow. Temporal variability in drainflow quality is affected in part by the distribution of chemical constituents in ground water and the flow paths to the drainage systems. The mass flux of selenium in drainflows, or load, generally is proportional to flow, and reductions in drainflow quantity should reduce selenium loads over the short-term. Uncertain changes in the distribution of ground-water quality make future changes in drainflow quality difficult to quantify.

Partial photoionization cross sections of NH4 and H3O Rydberg radicals

NASA Astrophysics Data System (ADS)

Velasco, A. M.; Lavín, C.; Martín, I.; Melin, J.; Ortiz, J. V.

2009-07-01

Photoionization cross sections for various Rydberg series that correspond to ionization channels of ammonium and oxonium Rydberg radicals from the outermost, occupied orbitals of their respective ground states are reported. These properties are known to be relevant in photoelectron dynamics studies. For the present calculations, the molecular-adapted quantum defect orbital method has been employed. A Cooper minimum has been found in the 3sa1-kpt2 Rydberg channel of NH4 beyond the ionization threshold, which provides the main contribution to the photoionization of this radical. However, no net minimum is found in the partial cross section of H3O despite the presence of minima in the 3sa1-kpe and 3sa1-kpa1 Rydberg channels. The complete oscillator strength distributions spanning the discrete and continuous regions of both radicals exhibit the expected continuity across the ionization threshold.

PARTIAL RESTRAINING FORCE INTRODUCTION METHOD FOR DESIGNING CONSTRUCTION COUNTERMESURE ON ΔB METHOD

NASA Astrophysics Data System (ADS)

Nishiyama, Taku; Imanishi, Hajime; Chiba, Noriyuki; Ito, Takao

Landslide or slope failure is a three-dimensional movement phenomenon, thus a three-dimensional treatment makes it easier to understand stability. The ΔB method (simplified three-dimensional slope stability analysis method) is based on the limit equilibrium method and equals to an approximate three-dimensional slope stability analysis that extends two-dimensional cross-section stability analysis results to assess stability. This analysis can be conducted using conventional spreadsheets or two-dimensional slope stability computational software. This paper describes the concept of the partial restraining force in-troduction method for designing construction countermeasures using the distribution of the restraining force found along survey lines, which is based on the distribution of survey line safety factors derived from the above-stated analysis. This paper also presents the transverse distributive method of restraining force used for planning ground stabilizing on the basis of the example analysis.

Theoretical studies of photoexcitation and ionization in H2O

NASA Technical Reports Server (NTRS)

Diercksen, G. H. F.; Kraemer, W. P.; Rescigno, T. N.; Bender, C. F.; Mckoy, B. V.; Langhoff, S. R.; Langhoff, P. W.

1982-01-01

Theoretical studies using Franck-Condon and static-exchange approximations are reported for the complete dipole excitation and ionization spectrum in H2O, where (1) large Cartesian Gaussian basis sets are used to represent the required discrete and continuum electronic eigenfunctions at the ground state equilibrium geometry, and (2) previously devised moment-theory techniques are employed in constructing the continuum oscillator-strength densities from the calculated spectra. Comparisons are made of the calculated excitation and ionization profiles with recent experimental photoabsorption studies and corresponding spectral assignments, electron impact-excitation cross sections, and dipole and synchrotron-radiation studies of partial-channel photoionization cross sections. The calculated partial-channel cross sections are found to be atomic-like, and dominated by 2p-kd components. It is suggested that the latter transition couples with the underlying 1b(1)-kb(1) channel, accounting for a prominent feature in recent synchrotron-radiation measurements.

Electrostatic interactions guide the active site face of a structure-specific ribonuclease to its RNA substrate.

PubMed

Plantinga, Matthew J; Korennykh, Alexei V; Piccirilli, Joseph A; Correll, Carl C

2008-08-26

Restrictocin, a member of the alpha-sarcin family of site-specific endoribonucleases, uses electrostatic interactions to bind to the ribosome and to RNA oligonucleotides, including the minimal specific substrate, the sarcin/ricin loop (SRL) of 23S-28S rRNA. Restrictocin binds to the SRL by forming a ground-state E:S complex that is stabilized predominantly by Coulomb interactions and depends on neither the sequence nor structure of the RNA, suggesting a nonspecific complex. The 22 cationic residues of restrictocin are dispersed throughout this protein surface, complicating a priori identification of a Coulomb interacting surface. Structural studies have identified an enzyme-substrate interface, which is expected to overlap with the electrostatic E:S interface. Here, we identified restrictocin residues that contribute to binding in the E:S complex by determining the salt dependence [partial differential log(k 2/ K 1/2)/ partial differential log[KCl

Water resources data, Ohio, water year 2003 : Volume 1. Ohio River basin excluding project data

USGS Publications Warehouse

Shindel, H.L.; Mangus, J.P.; Frum, S.R.

2004-01-01

Water-resources data for the 2003 water year for Ohio consist of records of stage, discharge, and water quality of streams; stage and contents of lakes and reservoirs; and water levels and water quality of ground-water wells. This report, in two volumes, contains records for water discharge at 138 gaging stations and various partial-record sites; water levels at 217 observation wells and 35 crest-stage gages; and water quality at 30 gaging stations, 34 observation wells, and no partial-record sites. Also included are data from miscellaneous and synoptic sites. Additional water data were collected at various sites not involved in the systematic data-collection program and are published as miscellaneous measurements and analyses. These data represent that part of the National Water Information System collected by the U.S. Geological Survey and cooperating Federal, State, and local agencies in Ohio.

Water resources data, Ohio, water year 2003: Volume 2. St. Lawrence River basin and statewide project data

USGS Publications Warehouse

Shindel, H.L.; Mangus, J.P.; Frum, S.R.

2004-01-01

Water-resources data for the 2003 water year for Ohio consist of records of stage, discharge, and water quality of streams; stage and contents of lakes and reservoirs; and water levels and water quality of ground-water wells. This report, in two volumes, contains records for water discharge at 138 gaging stations and various partial-record sites; water levels at 217 observation wells and 35 crest-stage gages; and water quality at 30 gaging stations, 34 observation wells, and no partial-record sites. Also included are data from miscellaneous and synoptic sites. Additional water data were collected at various sites not involved in the systematic data-collection program and are published as miscellaneous measurements and analyses. These data represent that part of the National Water Information System collected by the U.S. Geological Survey and cooperating Federal, State, and local agencies in Ohio.

Optical conductivity of partially oxidized graphene from first principles

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nasehnia, F., E-mail: f.nasehnia@gmail.com; Seifi, M., E-mail: Seifi@guilan.ac.ir

2015-07-07

We investigate the geometry, electronic structure, and optical properties of partially oxidized graphene using density functional theory. Our calculations show that oxygen atoms are chemisorbed on graphene plane and distort carbon atoms vertically, with almost no change in the in-plane structure. The ground state configurations for different oxygen coverages ranging from 2% to 50% (O/C ratio) are calculated and show the strong tendency of oxygen adatoms to aggregate and form discrete islands on graphene plane. It is found that the opened band gap due to oxygen functionalization depends on the oxygen density and the adsorption configuration. The gap is notmore » significant for oxygen densities lower than 8%. The optical conductivities are calculated in the infrared, visible, and ultraviolet regions and show different characteristic features depending on the degree of oxidation. These results imply that optical measurement techniques can be employed to monitor oxidation (or reduction) process as contact-free methods.« less

Standardization of Ga-68 by coincidence measurements, liquid scintillation counting and 4πγ counting.

PubMed

Roteta, Miguel; Peyres, Virginia; Rodríguez Barquero, Leonor; García-Toraño, Eduardo; Arenillas, Pablo; Balpardo, Christian; Rodrígues, Darío; Llovera, Roberto

2012-09-01

The radionuclide (68)Ga is one of the few positron emitters that can be prepared in-house without the use of a cyclotron. It disintegrates to the ground state of (68)Zn partially by positron emission (89.1%) with a maximum energy of 1899.1 keV, and partially by electron capture (10.9%). This nuclide has been standardized in the frame of a cooperation project between the Radionuclide Metrology laboratories from CIEMAT (Spain) and CNEA (Argentina). Measurements involved several techniques: 4πβ-γ coincidences, integral gamma counting and Liquid Scintillation Counting using the triple to double coincidence ratio and the CIEMAT/NIST methods. Given the short half-life of the radionuclide assayed, a direct comparison between results from both laboratories was excluded and a comparison of experimental efficiencies of similar NaI detectors was used instead. Copyright © 2012 Elsevier Ltd. All rights reserved.

Statistical properties of single-mode fiber coupling of satellite-to-ground laser links partially corrected by adaptive optics.

PubMed

Canuet, Lucien; Védrenne, Nicolas; Conan, Jean-Marc; Petit, Cyril; Artaud, Geraldine; Rissons, Angelique; Lacan, Jerome

2018-01-01

In the framework of satellite-to-ground laser downlinks, an analytical model describing the variations of the instantaneous coupled flux into a single-mode fiber after correction of the incoming wavefront by partial adaptive optics (AO) is presented. Expressions for the probability density function and the cumulative distribution function as well as for the average fading duration and fading duration distribution of the corrected coupled flux are given. These results are of prime interest for the computation of metrics related to coded transmissions over correlated channels, and they are confronted by end-to-end wave-optics simulations in the case of a geosynchronous satellite (GEO)-to-ground and a low earth orbit satellite (LEO)-to-ground scenario. Eventually, the impact of different AO performances on the aforementioned fading duration distribution is analytically investigated for both scenarios.

Preparation of Vibrationally Excited H2 in a Coherent Superposition of M-States Using Stark Induced Adiabatic Raman Passage (SARP)

NASA Astrophysics Data System (ADS)

Mukherjee, Nandini; Dong, Wenrui; Perreault, William; Zare, Richard

2017-04-01

We prepare a large ensemble of rovibrationally excited (v = 1, J = 2) H2 molecules in a coherent superposition of M-states using Stark-induced adiabatic Raman passage (SARP) with linearly polarized single mode pump (532 nm) and Stokes (699 nm) laser pulses of duration 6 ns and 4 ns. A biaxial superposition state, | ψ〉 = 1/ √2 [ | v = 1, J = 2, M = -2〉- | v = 1, J = 2, M = + 2〉], is prepared using SARP with a sequence of a pump laser pulse partially overlapping with a cross polarized Stokes laser pulse co-propagating along the quantization z-axis. The degree of phase coherence is measured by recording interference fringes in the ion signal produced using the O(2) line of 2 +1 resonance enhanced multiphoton ionization (REMPI) from the rovibrationally excited (v = 1, J = 2) level as a function of REMPI laser polarization angle. The ion signal is measured using a time-of-flight mass spectrometer. Nearly 60% population transfer from H2 (v = 0, J = 0) ground state to the superposition state in H2 (v = 1, J = 2) is measured from the depletion of Q(0) REMPI signal of the (v = 0, J = 0) ground state. The M-state superposition behaves much like a multi-slit interferometer where the number of slits, i.e. the number of M-states, and their separations, i.e. the relative phase, can be varied experimentally. This work has been supported by the U.S. Army Research Office.

Coriolis-coupled wave packet dynamics of H + HLi reaction.

PubMed

Padmanaban, R; Mahapatra, S

2006-05-11

We investigated the effect of Coriolis coupling (CC) on the initial state-selected dynamics of H+HLi reaction by a time-dependent wave packet (WP) approach. Exact quantum scattering calculations were obtained by a WP propagation method based on the Chebyshev polynomial scheme and ab initio potential energy surface of the reacting system. Partial wave contributions up to the total angular momentum J=30 were found to be necessary for the scattering of HLi in its vibrational and rotational ground state up to a collision energy approximately 0.75 eV. For each J value, the projection quantum number K was varied from 0 to min (J, K(max)), with K(max)=8 until J=20 and K(max)=4 for further higher J values. This is because further higher values of K do not have much effect on the dynamics and also because one wishes to maintain the large computational overhead for each calculation within the affordable limit. The initial state-selected integral reaction cross sections and thermal rate constants were calculated by summing up the contributions from all partial waves. These were compared with our previous results on the title system, obtained within the centrifugal sudden and J-shifting approximations, to demonstrate the impact of CC on the dynamics of this system.

Balloon Ascent: 3-D Simulation Tool for the Ascent and Float of High-Altitude Balloons

NASA Technical Reports Server (NTRS)

Farley, Rodger E.

2005-01-01

The BalloonAscent balloon flight simulation code represents a from-scratch development using Visual Basic 5 as the software platform. The simulation code is a transient analysis of balloon flight, predicting the skin and gas temperatures along with the 3-D position and velocity in a time and spatially varying environment. There are manual and automated controls for gas valving and the dropping of ballast. Also, there are many handy calculators, such as appropriate free lift, and steady-state thermal solutions with temperature gradients. The strength of this simulation model over others in the past is that the infrared environment is deterministic rather than guessed at. The ground temperature is specified along with the emissivity, which creates a ground level IR environment that is then partially absorbed as it travels upward through the atmosphere to the altitude of the balloon.

Accurate quantum wave packet calculations for the F + HCl → Cl + HF reaction on the ground 1(2)A' potential energy surface.

PubMed

Bulut, Niyazi; Kłos, Jacek; Alexander, Millard H

2012-03-14

We present converged exact quantum wave packet calculations of reaction probabilities, integral cross sections, and thermal rate coefficients for the title reaction. Calculations have been carried out on the ground 1(2)A' global adiabatic potential energy surface of Deskevich et al. [J. Chem. Phys. 124, 224303 (2006)]. Converged wave packet reaction probabilities at selected values of the total angular momentum up to a partial wave of J = 140 with the HCl reagent initially selected in the v = 0, j = 0-16 rovibrational states have been obtained for the collision energy range from threshold up to 0.8 eV. The present calculations confirm an important enhancement of reactivity with rotational excitation of the HCl molecule. First, accurate integral cross sections and rate constants have been calculated and compared with the available experimental data.

Vibrational energy transfer dynamics in ruthenium polypyridine transition metal complexes.

PubMed

Fedoseeva, Marina; Delor, Milan; Parker, Simon C; Sazanovich, Igor V; Towrie, Michael; Parker, Anthony W; Weinstein, Julia A

2015-01-21

Understanding the dynamics of the initial stages of vibrational energy transfer in transition metal complexes is a challenging fundamental question which is also of crucial importance for many applications, such as improving the performance of solar devices or photocatalysis. The present study investigates vibrational energy transport in the ground and the electronic excited state of Ru(4,4'-(COOEt)2-2,2-bpy)2(NCS)2, a close relative of the efficient "N3" dye used in dye-sensitized solar cells. Using the emerging technique of ultrafast two-dimensional infrared spectroscopy, we show that, similarly to other transition-metal complexes, the central Ru heavy atom acts as a "bottleneck" making the energy transfer from small ligands with high energy vibrational stretching frequencies less favorable and thereby affecting the efficiency of vibrational energy flow in the complex. Comparison of the vibrational relaxation times in the electronic ground and excited state of Ru(4,4'-(COOEt)2-2,2-bpy)2(NCS)2 shows that it is dramatically faster in the latter. We propose to explain this observation by the intramolecular electrostatic interactions between the thiocyanate group and partially oxidised Ru metal center, which increase the degree of vibrational coupling between CN and Ru-N modes in the excited state thus reducing structural and thermodynamic barriers that slow down vibrational relaxation and energy transport in the electronic ground state. As a very similar behavior was earlier observed in another transition-metal complex, Re(4,4'-(COOEt)2-2,2'-bpy)(CO)3Cl, we suggest that this effect in vibrational energy dynamics might be common for transition-metal complexes with heavy central atoms.

Decay of the neutron-rich isotope 171Ho and the identification of 169Dy

NASA Astrophysics Data System (ADS)

Chasteler, R. M.; Nitschke, J. M.; Firestone, R. B.; Vierinen, K. S.; Wilmarth, P. A.

1990-10-01

Neutron-rich rare-earth isotopes were produced in multinucleon transfer reactions between 170Er ions and natW targets. On-line mass separation was used together with β- and γ-ray spectroscopy in these studies. At mass A=169, the heaviest known dysprosium isotope, 39(8) s,169Dy, was identified. It was observed to β- decay to the ground state of 169Ho or through a level at 1578 keV. In the A=171 mass chain, a partial decay scheme for 55(3)-s 171Ho was determined.

Exploratory study of partial isolation of highway bridges.

DOT National Transportation Integrated Search

2011-01-01

A special class of seismically isolated bridges shares a common feature in that both ends of the superstructure are restrained and isolators over the columns of bridge uncouple the superstructure from the ground motions. They are defined as partial i...

Comprehension of Spacecraft Telemetry Using Hierarchical Specifications of Behavior

NASA Technical Reports Server (NTRS)

Havelund, Klaus; Joshi, Rajeev

2014-01-01

A key challenge in operating remote spacecraft is that ground operators must rely on the limited visibility available through spacecraft telemetry in order to assess spacecraft health and operational status. We describe a tool for processing spacecraft telemetry that allows ground operators to impose structure on received telemetry in order to achieve a better comprehension of system state. A key element of our approach is the design of a domain-specific language that allows operators to express models of expected system behavior using partial specifications. The language allows behavior specifications with data fields, similar to other recent runtime verification systems. What is notable about our approach is the ability to develop hierarchical specifications of behavior. The language is implemented as an internal DSL in the Scala programming language that synthesizes rules from patterns of specification behavior. The rules are automatically applied to received telemetry and the inferred behaviors are available to ground operators using a visualization interface that makes it easier to understand and track spacecraft state. We describe initial results from applying our tool to telemetry received from the Curiosity rover currently roving the surface of Mars, where the visualizations are being used to trend subsystem behaviors, in order to identify potential problems before they happen. However, the technology is completely general and can be applied to any system that generates telemetry such as event logs.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hou, Gao-Lei; Wang, Xue-Bin; McCoy, Anne B.

The transition-state (TS) region of the simplest heavy-light-heavy type of reaction, F• + H-F F-H + F•, is investigated in this work by a joint experimental and theoretical approach. Photodetaching the bifluride anion, [F…H…F]–, generates a negative ion photoelectron (NIPE) spectrum with three partially resolved bands in the electron binding energy (eBE) range of 5.4 – 7.0 eV. These bands correspond to the transition from the ground state of the anion to the electronic ground state of [F-H-F]• neutral, with associated vibrational excitations. The significant increase of eBE of the bifluride anion, relative to that of F-, reflects a hydrogenmore » bond energy between F- and HF of 46 kcal/mol. Theoretical modeling reveals that the antisymmetric motion of H between the two F atoms, near the TS on the neutral [F-H-F]• surface, dominates the observed three bands, while the F-H-F bending, F—F symmetric stretching modes, and the couplings between them is calculated to account for the breadth of the observed spectrum. From the NIPE spectrum, a lower limit on the activation enthalpy for F• + H-F F-H + F can be estimated to be H‡ = 12 ± 2 kcal/mol, a value below that of H‡ = 14.9 kcal/mol, given by our G4 calculations.« less

High-Resolution Infrared Spectra of Spiropentane, C5H8

DOE Office of Scientific and Technical Information (OSTI.GOV)

Price, Joseph E.; Coulterpark, K. A.; Masiello, Tony

2011-09-01

Infrared spectra of spiropentane (C{sub 5}H{sub 8}) have been recorded at a resolution (0.002 cm{sup -1}) sufficient to resolve for the first time individual rovibrational lines. This initial report presents the ground state constants for this molecule determined from the detailed analysis of the {nu}16 (b2) parallel band at 993 cm{sup -1}. In addition, the determination included more than 2000 ground state combination-differences deduced from partial analyses of four other infrared-allowed bands, the {nu}24(e) perpendicular band at 780 cm{sup -1} and three (b2) parallel bands at 1540 cm{sup -1} ({nu}14), 1568 cm{sup -1} ({nu}5+{nu}16), and 2098 cm{sup -1} ({nu}5+{nu}14). Inmore » each of the latter four cases, the spectra show complications; in the case of {nu}24, these complications are due to rotational l-type doublings, and in the case of the parallel bands, the spectral complexities are due to Fermi resonance and Coriolis interactions of the upper states with nearby levels. The unraveling of these is underway but the assignment of many of these transitions permit the confident use of the ground state differences in determining the following constants for the ground state (in units of cm{sup -1}): B0 = 0.1394736(2), DJ = 2.458(1) x 10{sup -8}, DJK = 8.28(3) x 10{sup -8}. For the unperturbed {nu}16 fundamental, more than 3000 transitions were fit and the band origin was found to be at 992.53793(2) cm{sup -1}. The numbers in parentheses are the uncertainties (two standard deviations) in the value of the last digit of the constants. Surprisingly, the very accurate B0 value measured here is lower than the value (0.1418 cm{sup -1}) calculated from an electron diffraction structure, instead of being higher, as expected. Where possible, the rovibrational results are compared with those computed at the anharmonic level using the B3LYP density functional method with a cc-pVTZ basis set. These too suggest that the electron diffraction results are in question.« less

Topological entanglement entropy of fracton stabilizer codes

NASA Astrophysics Data System (ADS)

Ma, Han; Schmitz, A. T.; Parameswaran, S. A.; Hermele, Michael; Nandkishore, Rahul M.

2018-03-01

Entanglement entropy provides a powerful characterization of two-dimensional gapped topological phases of quantum matter, intimately tied to their description by topological quantum field theories (TQFTs). Fracton topological orders are three-dimensional gapped topologically ordered states of matter that lack a TQFT description. We show that three-dimensional fracton phases are nevertheless characterized, at least partially, by universal structure in the entanglement entropy of their ground-state wave functions. We explicitly compute the entanglement entropy for two archetypal fracton models, the "X-cube model" and "Haah's code," and demonstrate the existence of a nonlocal contribution that scales linearly in subsystem size. We show via Schrieffer-Wolff transformations that this piece of the entanglement entropy of fracton models is robust against arbitrary local perturbations of the Hamiltonian. Finally, we argue that these results may be extended to characterize localization-protected fracton topological order in excited states of disordered fracton models.

Neutron single-particle strengths at N = 40 , 42: Neutron knockout from Ni 68 , 70 ground and isomeric states

DOE PAGES

Recchia, F.; Weisshaar, D.; Gade, A.; ...

2016-11-28

The distribution of single-particle strength in 67,69Ni was characterized with one-neutron knockout reactions from intermediate-energy 68,70Ni secondary beams, selectively populating neutron-hole configurations at N = 39 and 41, respectively. The spectroscopic strengths deduced from the measured partial cross sections to the individual final states, as tagged by their γ-ray decays, is used to identify and quantify neutron configurations in the wave functions. While 69Ni compares well to shell-model predictions, the results for 67Ni challenge the validity of current effective shell-model Hamiltonians by revealing discrepancies that cannot be explained so far. Furthermore, these results suggest that our understanding of the low-lyingmore » states in the neutron-rich, semi-magic Ni isotopes may be incomplete and requires further investigation on both the experimental and theoretical sides.« less

Interaction of moving branes with background massless and tachyon fields in superstring theory

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rezaei, Z., E-mail: z.rezaei@aut.ac.ir; Kamani, D., E-mail: kamani@aut.ac.ir

2012-02-15

Using the boundary state formalism, we study a moving Dp-brane in a partially compact space-time in the presence of background fields: the Kalb-Ramond field B{sub {mu}{nu}}, a U(1) gauge field A{sub {alpha}}, and the tachyon field. The boundary state enables us to obtain the interaction amplitude of two branes with the above back-ground fields. The branes are parallel or perpendicular to each other. Because of the presence of background fields, compactification of some space-time directions, motion of the branes, and the arbitrariness of the dimensions of the branes, the system is rather general. Due to the tachyon fields and velocitiesmore » of the branes, the behavior of the interaction amplitude reveals obvious differences from the conventional behavior.« less

Recycling and processing of several typical crosslinked polymer scraps with enhanced mechanical properties based on solid-state mechanochemical milling

NASA Astrophysics Data System (ADS)

Lu, Canhui; Zhang, Xinxing; Zhang, Wei

2015-05-01

The partially devulcanization or de-crosslinking of ground tire rubber (GTR), post-vulcanized fluororubber scraps and crosslinked polyethylene from cable scraps through high-shear mechanochemical milling (HSMM) was conducted by a modified solid-state mechanochemical reactor. The results indicated that the HSMM treated crosslinked polymer scraps can be reprocessed as virgin rubbers or thermoplastics to produce materials with high performance. The foamed composites of low density polyethylene/GTR and the blend of post-vulcanized flurorubber (FKM) with polyacrylate rubber (ACM) with better processability and mechanical properties were obtained. The morphology observation showed that the dispersion and compatibility between de-crosslinked polymer scraps and matrix were enhanced. The results demonstrated that HSMM is a feasible alternative technology for recycling post-vulcanized or crosslinked polymer scraps.

Guide to the Revised Ground-Water Flow and Heat Transport Simulator: HYDROTHERM - Version 3

USGS Publications Warehouse

Kipp, Kenneth L.; Hsieh, Paul A.; Charlton, Scott R.

2008-01-01

The HYDROTHERM computer program simulates multi-phase ground-water flow and associated thermal energy transport in three dimensions. It can handle high fluid pressures, up to 1 ? 109 pascals (104 atmospheres), and high temperatures, up to 1,200 degrees Celsius. This report documents the release of Version 3, which includes various additions, modifications, and corrections that have been made to the original simulator. Primary changes to the simulator include: (1) the ability to simulate unconfined ground-water flow, (2) a precipitation-recharge boundary condition, (3) a seepage-surface boundary condition at the land surface, (4) the removal of the limitation that a specified-pressure boundary also have a specified temperature, (5) a new iterative solver for the linear equations based on a generalized minimum-residual method, (6) the ability to use time- or depth-dependent functions for permeability, (7) the conversion of the program code to Fortran 90 to employ dynamic allocation of arrays, and (8) the incorporation of a graphical user interface (GUI) for input and output. The graphical user interface has been developed for defining a simulation, running the HYDROTHERM simulator interactively, and displaying the results. The combination of the graphical user interface and the HYDROTHERM simulator forms the HYDROTHERM INTERACTIVE (HTI) program. HTI can be used for two-dimensional simulations only. New features in Version 3 of the HYDROTHERM simulator have been verified using four test problems. Three problems come from the published literature and one problem was simulated by another partially saturated flow and thermal transport simulator. The test problems include: transient partially saturated vertical infiltration, transient one-dimensional horizontal infiltration, two-dimensional steady-state drainage with a seepage surface, and two-dimensional drainage with coupled heat transport. An example application to a hypothetical stratovolcano system with unconfined ground-water flow is presented in detail. It illustrates the use of HTI with the combination precipitation-recharge and seepage-surface boundary condition, and functions as a tutorial example problem for the new user.

Effect of Sampling Schedule on Pharmacokinetic Parameter Estimates of Promethazine in Astronauts

NASA Technical Reports Server (NTRS)

Boyd, Jason L.; Wang, Zuwei; Putcha, Lakshmi

2005-01-01

Six astronauts on the Shuttle Transport System (STS) participated in an investigation on the pharmacokinetics of promethazine (PMZ), a medication used for the treatment of space motion sickness (SMS) during flight. Each crewmember completed the protocol once during flight and repeated thirty days after returned to Earth. Saliva samples were collected at scheduled times for 72 h after PMZ administration; more frequent samples were collected on the ground than during flight owing to schedule constraints in flight. PMZ concentrations in saliva were determined by a liquid chromatographic/mass spectrometric (LC-MS) assay and pharmacokinetic parameters (PKPs) were calculated using actual flight and ground-based data sets and using time-matched sampling schedule on ground to that during flight. Volume of distribution (V(sub c)) and clearance (Cl(sub s),) decreased during flight compared to that from time-matched ground data set; however, Cl(sub s) and V(sub c) estimates were higher for all subjects when partial ground data sets were used for analysis. Area under the curve (AUC) normalized with administered dose was similar in flight and partial ground data; however AUC was significantly lower using time-matched sampling compared with the full data set on ground. Half life (t(sub 1/2)) was longest during flight, shorter with matched-sampling schedule on ground and shortest when complete data set from ground was used. Maximum concentration (C(sub max)), time for C(sub max), (t(sub max)), parameters of drug absorption, depicted a similar trend with lowest and longest respectively, during flight, lower with time-matched ground data and highest and shortest with full ground data.

Effect of sampling schedule on pharmacokinetic parameter estimates of promethazine in astronauts

NASA Astrophysics Data System (ADS)

Boyd, Jason L.; Wang, Zuwei; Putcha, Lakshmi

2005-08-01

Six astronauts on the Shuttle Transport System (STS) participated in an investigation on the pharmacokinetics of promethazine (PMZ), a medication used for the treatment of space motion sickness (SMS) during flight. Each crewmember completed the protocol once during flight and repeated thirty days after returned to Earth. Saliva samples were collected at scheduled times for 72 h after PMZ administration; more frequent samples were collected on the ground than during flight owing to schedule constraints in flight. PMZ concentrations in saliva were determined by a liquid chromatographic/mass spectrometric (LC-MS) assay and pharmacokinetic parameters (PKPs) were calculated using actual flight and ground-based data sets and using time-matched sampling schedule on ground to that during flight. Volume of distribution (Vc) and clearance (Cls) decreased during flight compared to that from time-matched ground data set; however, ClS and Vc estimates were higher for all subjects when partial ground data sets were used for analysis. Area under the curve (AUC) normalized with administered dose was similar in flight and partial ground data; however AUC was significantly lower using time-matched sampling compared with the full data set on ground. Half life (t1/2) was longest during flight, shorter with matched-sampling schedule on ground and shortest when complete data set from ground was used. Maximum concentration (Cmax), time for Cmax (tmax), parameters of drug absorption, depicted a similar trend with lowest and longest respectively, during flight, lower with time- matched ground data and highest and shortest with full ground data.

Electronic energy transfer through non-adiabatic vibrational-electronic resonance. I. Theory for a dimer

NASA Astrophysics Data System (ADS)

Tiwari, Vivek; Peters, William K.; Jonas, David M.

2017-10-01

Non-adiabatic vibrational-electronic resonance in the excited electronic states of natural photosynthetic antennas drastically alters the adiabatic framework, in which electronic energy transfer has been conventionally studied, and suggests the possibility of exploiting non-adiabatic dynamics for directed energy transfer. Here, a generalized dimer model incorporates asymmetries between pigments, coupling to the environment, and the doubly excited state relevant for nonlinear spectroscopy. For this generalized dimer model, the vibrational tuning vector that drives energy transfer is derived and connected to decoherence between singly excited states. A correlation vector is connected to decoherence between the ground state and the doubly excited state. Optical decoherence between the ground and singly excited states involves linear combinations of the correlation and tuning vectors. Excitonic coupling modifies the tuning vector. The correlation and tuning vectors are not always orthogonal, and both can be asymmetric under pigment exchange, which affects energy transfer. For equal pigment vibrational frequencies, the nonadiabatic tuning vector becomes an anti-correlated delocalized linear combination of intramolecular vibrations of the two pigments, and the nonadiabatic energy transfer dynamics become separable. With exchange symmetry, the correlation and tuning vectors become delocalized intramolecular vibrations that are symmetric and antisymmetric under pigment exchange. Diabatic criteria for vibrational-excitonic resonance demonstrate that anti-correlated vibrations increase the range and speed of vibronically resonant energy transfer (the Golden Rule rate is a factor of 2 faster). A partial trace analysis shows that vibronic decoherence for a vibrational-excitonic resonance between two excitons is slower than their purely excitonic decoherence.

Electronic energy transfer through non-adiabatic vibrational-electronic resonance. I. Theory for a dimer.

PubMed

Tiwari, Vivek; Peters, William K; Jonas, David M

2017-10-21

Non-adiabatic vibrational-electronic resonance in the excited electronic states of natural photosynthetic antennas drastically alters the adiabatic framework, in which electronic energy transfer has been conventionally studied, and suggests the possibility of exploiting non-adiabatic dynamics for directed energy transfer. Here, a generalized dimer model incorporates asymmetries between pigments, coupling to the environment, and the doubly excited state relevant for nonlinear spectroscopy. For this generalized dimer model, the vibrational tuning vector that drives energy transfer is derived and connected to decoherence between singly excited states. A correlation vector is connected to decoherence between the ground state and the doubly excited state. Optical decoherence between the ground and singly excited states involves linear combinations of the correlation and tuning vectors. Excitonic coupling modifies the tuning vector. The correlation and tuning vectors are not always orthogonal, and both can be asymmetric under pigment exchange, which affects energy transfer. For equal pigment vibrational frequencies, the nonadiabatic tuning vector becomes an anti-correlated delocalized linear combination of intramolecular vibrations of the two pigments, and the nonadiabatic energy transfer dynamics become separable. With exchange symmetry, the correlation and tuning vectors become delocalized intramolecular vibrations that are symmetric and antisymmetric under pigment exchange. Diabatic criteria for vibrational-excitonic resonance demonstrate that anti-correlated vibrations increase the range and speed of vibronically resonant energy transfer (the Golden Rule rate is a factor of 2 faster). A partial trace analysis shows that vibronic decoherence for a vibrational-excitonic resonance between two excitons is slower than their purely excitonic decoherence.

Evaluating Lightning-generated NOx (LNOx) Parameterization based on Cloud Top Height at Resolutions with Partially-resolved Convection for Upper Tropospheric Chemistry Studies

NASA Astrophysics Data System (ADS)

Wong, J.; Barth, M. C.; Noone, D. C.

2012-12-01

Lightning-generated nitrogen oxides (LNOx) is an important precursor to tropospheric ozone production. With a meteorological time-scale variability similar to that of the ozone chemical lifetime, it can nonlinearly perturb tropospheric ozone concentration. Coupled with upper-air circulation patterns, LNOx can accumulate in significant amount in the upper troposphere with other precursors, thus enhancing ozone production (see attached figure). While LNOx emission has been included and tuned extensively in global climate models, its inclusions in regional chemistry models are seldom tested. Here we present a study that evaluates the frequently used Price and Rind parameterization based on cloud-top height at resolutions that partially resolve deep convection using the Weather Research and Forecasting model with Chemistry (WRF-Chem) over the contiguous United States. With minor modifications, the parameterization is shown to generate integrated flash counts close to those observed. However, the modeled frequency distribution of cloud-to-ground flashes do not represent well for storms with high flash rates, bringing into question the applicability of the intra-cloud/ground partitioning (IC:CG) formulation of Price and Rind in some studies. Resolution dependency also requires attention when sub-grid cloud-tops are used instead of the originally intended grid-averaged cloud-top. LNOx passive tracers being gathered by monsoonal upper tropospheric anticyclone.

Water resources data, Idaho, 2004; Volume 2. Surface water records for Upper Columbia River basin and Great Basin below King Hill

USGS Publications Warehouse

Brennan, T.S.; Lehmann, A.K.; O'Dell, I.

2005-01-01

Water resources data for the 2004 water year for Idaho consists of records of stage, discharge, and water quality of streams; stage, contents, and water quality of lakes and reservoirs; discharge of irrigation diversions; and water levels and water quality of groundwater. The three volumes of this report contain discharge records for 209 stream-gaging stations and 8 irrigation diversions; stage only records for 6 stream-gaging stations; stage only for 6 lakes and reservoirs; contents only for 13 lakes and reservoirs; water-quality for 39 stream-gaging stations and partial record sites, 3 lakes sites, and 395 groundwater wells; and water levels for 425 observation network wells. Additional water data were collected at various sites not involved in the systematic data collection program and are published as miscellaneous measurements. Volumes 1 & 2 contain the surface-water and surface-water-quality records. Volume 3 contains the ground-water and ground-water-quality records. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State and Federal agencies in Idaho, adjacent States, and Canada.

Water resources data, Idaho, 2003; Volume 2. Surface water records for Upper Columbia River basin and Great Basin below King Hill

USGS Publications Warehouse

Brennan, T.S.; Lehmann, A.K.; O'Dell, I.

2004-01-01

Water resources data for the 2003 water year for Idaho consists of records of stage, discharge, and water quality of streams; stage, contents, and water quality of lakes and reservoirs; discharge of irrigation diversions; and water levels and water quality of groundwater. The three volumes of this report contain discharge records for 208 stream-gaging stations and 14 irrigation diversions; stage only records for 6 stream-gaging stations; stage only for 6 lakes and reservoirs; contents only for 13 lakes and reservoirs; water-quality for 50 stream-gaging stations and partial record sites, 3 lakes sites, and 398 groundwater wells; and water levels for 427 observation network wells and 900 special project wells. Additional water data were collected at various sites not involved in the systematic data collection program and are published as miscellaneous measurements. Volumes 1 & 2 contain the surface-water and surface-water-quality records. Volume 3 contains the ground-water and ground-water-quality records. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State and Federal agencies in Idaho, adjacent States, and Canada.

Water resources data, Idaho, 2003; Volume 1. Surface water records for Great Basin and Snake River basin above King Hill

USGS Publications Warehouse

Brennan, T.S.; Lehmann, A.K.; O'Dell, I.

2004-01-01

Water resources data for the 2003 water year for Idaho consists of records of stage, discharge, and water quality of streams; stage, contents, and water quality of lakes and reservoirs; discharge of irrigation diversions; and water levels and water quality of groundwater. The three volumes of this report contain discharge records for 208 stream-gaging stations and 14 irrigation diversions; stage only records for 6 stream-gaging stations; stage only for 6 lakes and reservoirs; contents only for 13 lakes and reservoirs; water-quality for 50 stream-gaging stations and partial record sites, 3 lakes sites, and 398 groundwater wells; and water levels for 427 observation network wells and 900 special project wells. Additional water data were collected at various sites not involved in the systematic data collection program and are published as miscellaneous measurements. Volumes 1 & 2 contain the surface-water and surface-water-quality records. Volume 3 contains the ground-water and ground-water-quality records. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State and Federal agencies in Idaho, adjacent States, and Canada.

Water resources data, Idaho, 2004; Volume 1. Surface water records for Great Basin and Snake River basin above King Hill

USGS Publications Warehouse

Brennan, T.S.; Lehmann, A.K.; O'Dell, I.

2005-01-01

Water resources data for the 2004 water year for Idaho consists of records of stage, discharge, and water quality of streams; stage, contents, and water quality of lakes and reservoirs; discharge of irrigation diversions; and water levels and water quality of groundwater. The three volumes of this report contain discharge records for 209 stream-gaging stations and 8 irrigation diversions; stage only records for 6 stream-gaging stations; stage only for 6 lakes and reservoirs; contents only for 13 lakes and reservoirs; water-quality for 39 stream-gaging stations and partial record sites, 3 lakes sites, and 395 groundwater wells; and water levels for 425 observation network wells and 900 special project wells. Additional water data were collected at various sites not involved in the systematic data collection program and are published as miscellaneous measurements. Volumes 1 & 2 contain the surface-water and surface-water-quality records. Volume 3 contains the ground-water and ground-water-quality records. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State and Federal agencies in Idaho, adjacent States, and Canada.

Derivation of the RPA (Random Phase Approximation) Equation of ATDDFT (Adiabatic Time Dependent Density Functional Ground State Response Theory) from an Excited State Variational Approach Based on the Ground State Functional.

PubMed

Ziegler, Tom; Krykunov, Mykhaylo; Autschbach, Jochen

2014-09-09

The random phase approximation (RPA) equation of adiabatic time dependent density functional ground state response theory (ATDDFT) has been used extensively in studies of excited states. It extracts information about excited states from frequency dependent ground state response properties and avoids, thus, in an elegant way, direct Kohn-Sham calculations on excited states in accordance with the status of DFT as a ground state theory. Thus, excitation energies can be found as resonance poles of frequency dependent ground state polarizability from the eigenvalues of the RPA equation. ATDDFT is approximate in that it makes use of a frequency independent energy kernel derived from the ground state functional. It is shown in this study that one can derive the RPA equation of ATDDFT from a purely variational approach in which stationary states above the ground state are located using our constricted variational DFT (CV-DFT) method and the ground state functional. Thus, locating stationary states above the ground state due to one-electron excitations with a ground state functional is completely equivalent to solving the RPA equation of TDDFT employing the same functional. The present study is an extension of a previous work in which we demonstrated the equivalence between ATDDFT and CV-DFT within the Tamm-Dancoff approximation.

Human Health Countermeasures - Partial-Gravity Analogs Workshop

NASA Technical Reports Server (NTRS)

Barr, Yael; Clement, Gilles; Norsk, Peter

2016-01-01

The experimental conditions that were deemed the most interesting by the HHC Element lead scientists are those permitting studies of the long-term effects of exposure to (a) chronic rotation when supine or in head down tilt (ground-based); and (b) long-radius centrifugation (space based). It is interesting to note that chronic ground based slow rotation room studies have not been performed since the 1960's, when the USA and USSR were investigating the potential use of AG for long-duration space missions. On the other hand, the other partial gravity analogs, i.e., parabolic flight, HUT, suspension, and short-radius centrifugation, have been regularly used in the last three decades (see review in Clément et al. 2015). Based on the workshop evaluations and the scores by the HHC scientific disciplines indicated in tables 3 and 4, simulation of partial G between 0 and 1 should be prioritized as follows: Priority 1. Chronic space-based partial-G analogs: a. Chronic space-based long-radius centrifugation. The ideal scenario would be chronic long-radius centrifugation of cells, animals and humans in a translational research approach - ideally beyond low earth orbit under deep space environmental effects and at various rotations - to obtain different G-effects. In this scenario, all physiological systems could be evaluated and the relationship between physiological response and G level established. This would be the most integrative way of defining, for the first time ever, G-thresholds for each physiological system. b. Chronic space-based centrifugation of animals. Chronic centrifugation of rodents at various G levels in space would allow for determination of AG thresholds of protection for each physiological system. In this case, all physiological systems will be of interest. Intermittent centrifugation will be of secondary interest. c. Chronic space-based centrifugation of cell cultures (RWV). Bioreactor studies of cells and cell cultures of various tissues at various G levels would allow for intracellular investigations of the effects of partial-G. Priority 2. Acute, intermittent space based partial-G analogs: a. Acute, intermittent space-based short radius human centrifugation. Intermittent centrifugation of humans would allow determination of thresholds of AG for protection of astronaut health in space. Priority 3. Chronic ground-based partial-G analogs: a. Chronic centrifugation of supine or head-down tilted humans. b. Chronic head-up tilt in humans. c. Chronic head-out graded dry immersion in humans. d. Chronic partial suspension of rodents e. Chronic rotating bioreactor cell culture studies (RWV) Priority 4. Acute ground based partial-G analogs. a. Parabolic flights. Very acute and short term effects of G levels between 0 and 1 in humans for fast responding systems like cardiovascular and sensorimotor as well as for acute responses in cell cultures and animals. b. Other acute models as indicated in table 3.

76 FR 11350 - National Oil and Hazardous Substances Pollution Contingency Plan; National Priorities List...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-03-02

... and Hazardous Substances Pollution Contingency Plan; National Priorities List: Partial Deletion of the... appendix of the National Oil and Hazardous Substances Pollution Contingency Plan (NCP). This partial deletion pertains to the soil and ground water associated with the northern 62-acre parcel. After this...

Zero-field-cooled/field-cooled magnetization study of Dendrimer model

NASA Astrophysics Data System (ADS)

Arejdal, M.; Bahmad, L.; Benyoussef, A.

2017-01-01

Being motivated by Dendrimer model with mixed spins σ=3 and S=7/2, we investigated the magnetic nanoparticle system in this study. We analyzed and discussed the ground-state phase diagrams and the stable phases. Then, we elaborated and explained the magnetic properties of the system by using Monte Carlo Simulations (MCS) in the framework of the Ising model. In this way, we determined the blocking temperature, which is deduced through studying the partial-total magnetization and susceptibility as a function of the temperature, and we established the effects of both the exchange coupling interaction and the crystal field on the hysteresis loop.

High Si-H local mode overtones in SiHD/sub 3/

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bernheim, R.A.; Lampe, F.W.; O'Keefe, J.F.

1984-01-01

Spectra for SiHD/sub 3/ obtained using a nonresonant photoacoustic cell mounted within the cavity of a CR490 tunable CW laser are reported herein. The symmetric top spectra exhibit partial rotational resolution. A relation for determining the Si-H bond distance is reported, and the Si-D bond distance is taken to be the same as the Si-H distance in the ground vibrational state. The bond angle is assumed to remain tetrahedral in both situations. The noted spectral vibrational band widths arise only from rotational structure with contributions from fast vibrational relaxation not being evident. 10 references, 2 figures, 1 table.

Correlation between size distribution and luminescence properties of spool-shaped InAs quantum dots

NASA Astrophysics Data System (ADS)

Xie, H.; Prioli, R.; Torelly, G.; Liu, H.; Fischer, A. M.; Jakomin, R.; Mourão, R.; Kawabata, R.; Pires, M. P.; Souza, P. L.; Ponce, F. A.

2017-05-01

InAs QDs embedded in an AlGaAs matrix have been produced by MOVPE with a partial capping and annealing technique to achieve controllable QD energy levels that could be useful for solar cell applications. The resulted spool-shaped QDs are around 5 nm in height and have a log-normal diameter distribution, which is observed by TEM to range from 5 to 15 nm. Two photoluminescence peaks associated with QD emission are attributed to the ground and the first excited states transitions. The luminescence peak width is correlated with the distribution of QD diameters through the diameter dependent QD energy levels.

Analysis of partial-reflection data from the solar eclipse of 10 Jul. 1972. [ground-based experiment using vertical incident radio waves partially reflected from D region

NASA Technical Reports Server (NTRS)

Bean, T. A.; Bowhill, S. A.

1973-01-01

Partial-reflection data collected for the eclipse of July 10, 1972 as well as for July 9 and 11, 1972, are analyzed to determine eclipse effects on D-region electron densities. The partial-reflection experiment was set up to collect data using an on-line PDP-15 computer and DECtape storage. The electron-density profiles show good agreement with results from other eclipses. The partial-reflection programs were changed after the eclipse data collection to improve the operation of the partial-reflection system. These changes were mainly due to expanded computer hardware and have simplified the operations of the system considerably.

Water Resources Data for Illinois - Water Year 2005 (Includes Historical Data)

USGS Publications Warehouse

LaTour, J.K.; Weldon, E.A.; Dupre, D.H.; Halfar, T.M.

2006-01-01

This annual Water-Data Report for Illinois contains current water year (Oct. 1, 2004, to Sept. 30, 2005) and historical data of discharge, stage, water quality and biology of streams; stage of lakes and reservoirs; levels and quality of ground water; and records of precipitation, air temperature, dew point, solar radiation, and wind speed. The current year's (2005) data provided in this report include (1) discharge for 182 surface-water gaging stations and for 9 crest-stage partial-record stations; (2) stage for 33 surface-water gaging stations; (3) water-quality records for 10 surface-water stations; (4) sediment-discharge records for 14 surface-water stations; (5) water-level records for 98 ground-water wells; (6) water-quality records for 17 ground-water wells; (7) precipitation records for 48 rain gages; (8) records of air temperature, dew point, solar radiation and wind speed for 1 meteorological station; and (9) biological records for 6 sample sites. Also included are miscellaneous data collected at various sites not in the systematic data-collection network. Data were collected and compiled as a part of the National Water Information System (NWIS) maintained by the U.S. Geological Survey in cooperation with Federal, State, and local agencies.

Magnetism and charge density wave in GdNiC2 and NdNiC2

NASA Astrophysics Data System (ADS)

Klimczuk, Tom; Kolincio, Kamil; Wianiarski, Michal; Strychalska-Nowak, Judyta; Górnicka, Karolina

The RNiC2 compounds form in an orthorhombic Amm2 crystal structure with Ni and the rare-earth (R) metal chains along the crystallographic a-axis. This system is of particular interest because both a CDW and a long range magnetic ordering phases have been observed together. We report the specific heat, magnetic, magnetotransport and galvanomagnetic properties of GdNiC2 and NdNiC2 antiferromagnets. Complex B-T phase diagrams were built based on the specific heat data. Large negative magnetoresistance due to Zeeman splitting of the electronic bands and partial destruction of a charge density wave ground state is observed above TN. The magnetoresistance and Hall measurements show that at low temperatures a magnetic field induced transformation from antiferromagnetic order to a metamagnetic phase results in the partial suppression of the CDW. This project is financially supported by National Science Centre (Poland), Grant Number: UMO-2015/19/B/ST3/03127.

Probing 5 f -state configurations in URu 2 Si 2 with U L III -edge resonant x-ray emission spectroscopy

DOE PAGES

Booth, Corwin H.; Medling, S. A.; Tobin, J. G.; ...

2016-07-15

Resonant x-ray emission spectroscopy (RXES) was employed at the U LIII absorption edge and the L α1 emission line to explore the 5f occupancy, nf, and the degree of 5f-orbital delocalization in the hidden-order compound URu 2Si 2. By comparing to suitable reference materials such as UF 4, UCd 11, and α-U, we conclude that the 5f orbital in URu 2Si 2 is at least partially delocalized with n f=2.87±0.08, and does not change with temperature down to 10 K within the estimated error. These results place further constraints on theoretical explanations of the hidden order, especially those requiring amore » localized f 2 ground state.« less

Recycling and processing of several typical crosslinked polymer scraps with enhanced mechanical properties based on solid-state mechanochemical milling

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lu, Canhui; Zhang, Xinxing; Zhang, Wei

The partially devulcanization or de-crosslinking of ground tire rubber (GTR), post-vulcanized fluororubber scraps and crosslinked polyethylene from cable scraps through high-shear mechanochemical milling (HSMM) was conducted by a modified solid-state mechanochemical reactor. The results indicated that the HSMM treated crosslinked polymer scraps can be reprocessed as virgin rubbers or thermoplastics to produce materials with high performance. The foamed composites of low density polyethylene/GTR and the blend of post-vulcanized flurorubber (FKM) with polyacrylate rubber (ACM) with better processability and mechanical properties were obtained. The morphology observation showed that the dispersion and compatibility between de-crosslinked polymer scraps and matrix were enhanced. Themore » results demonstrated that HSMM is a feasible alternative technology for recycling post-vulcanized or crosslinked polymer scraps.« less

First-principles studies of electronic, transport and bulk properties of pyrite FeS2

NASA Astrophysics Data System (ADS)

Banjara, Dipendra; Mbolle, Augustine; Malozovsky, Yuriy; Franklin, Lashounda; Bagayoko, Diola

We present results of ab-initio, self-consistent density functional theory (DFT) calculations of electronic, transport, and bulk properties of pyrite FeS2. We employed a local density approximation (LDA) potential and the linear combination of atomic orbitals (LCAO) formalism, following the Bagayoko, Zhao and Williams (BZW) method, as enhanced by Ekuma and Franklin (BZW-EF). The BZW-EF method requires successive, self consistent calculations with increasing basis sets to reach the ground state of the system under study. We report the band structure, the band gap, total and partial densities of states, effective masses, and the bulk modulus. Work funded in part by the US Department of Energy (DOE), National Nuclear Security Administration (NNSA) (Award No.DE-NA0002630), the National Science Foundation (NSF) (Award No, 1503226), LaSPACE, and LONI-SUBR.

2017 Total Solar Eclipse Science Briefing

NASA Image and Video Library

2017-06-21

During a June 21 media briefing from the Newseum in Washington, representatives from NASA, other federal agencies, and science organizations discussed the opportunity for scientific study offered by the total solar eclipse that will cross the U.S. on August 21. Over the course of 100 minutes, 14 states across the United States will experience more than two minutes of darkness in the middle of the day. Additionally, a partial eclipse will be viewable across all of North America. The eclipse will provide a unique opportunity to study the sun, Earth, moon and their interaction because of the eclipse’s long path over land coast to coast. Scientists will be able to take ground-based and airborne observations over a period of an hour and a half to complement the wealth of data and images provided by space assets.

Properties of concrete containing ground palm oil fuel ash as fine aggregate replacement

NASA Astrophysics Data System (ADS)

Saffuan, W. A.; Muthusamy, K.; Salleh, N. A. Mohd; Nordin, N.

2017-11-01

Environmental degradation resulting from increasing sand mining activities and disposal of palm oil fuel ash (POFA), a solid waste generated from palm oil mill needs to be resolved. Thus, the present research investigates the effect of ground palm oil fuel ash as partial fine aggregate replacement on workability, compressive and flexural strength of concrete. Five mixtures of concrete containing POFA as partial sand replacement designed with 0%, 10%, 20%, 30% and 40% of POFA by the weight of sand were used in this experimental work. The cube and beam specimens were casted and water cured up to 28 days before subjected to compressive strength and flexural strength testing respectively. Finding shows that concrete workability reduces as the amount of POFA added become larger. It is worth to note that 10% of POFA is the best amount to be used as partial fine aggregate replacement to produce concrete with enhanced strength.

Magnetoelectric properties of Pb free Bi2FeTiO6: A theoretical investigation

NASA Astrophysics Data System (ADS)

Patra, Lokanath; Ravindran, P.

2018-05-01

The structural, electronic, magnetic and ferroelectric properties of Pb free double perovskite multiferroic Bi2FeTiO6 are investigated using density functional theory within the general gradient approximation (GGA) method. Our structural optimization using total energy calculations for different potential structures show a minimum energy for a non-centrosymmetric rhombohedral structure with R3c space group. Bi2FeTiO6 is found to be an antiferromagnetic insulator with C-type magnetic ordering with bandgap value of 0.3 eV. The calculated magnetic moment of 3.52 μB at Fe site shows the high spin arrangement of 3d electrons which is also confirmed by our orbital projected density of states analysis. We have analyzed the characteristics of bonding present between the constituents of Bi2FeTiO6 with the help of calculated partial density of states and Born effective charges. The ground state of the nearest centrosymmetric structure is found to be a G-type antiferromagnet with half metallicity showing that by the application of external electric field we can not only get a polarized state but also change the magnetic ordering and electronic structure in the present compound indicating strong magnetoelectric coupling. The cation sites the coexistence of Bi 6s lone pair (bring disproportionate charge distribution) and Ti4+ d0 ions which brings covalency produces off-center displacement and favors a non-centrosymmetric ground state and thus ferroelectricity. Our Berry phase calculation gives a polarization of 48 µCcm-2 for Bi2FeTiO6.

The Microscope Space Mission and the In-Orbit Calibration Plan for its Instrument

NASA Astrophysics Data System (ADS)

Levy, Agnès Touboul, Pierre; Rodrigues, Manuel; Onera, Émilie Hardy; Métris, Gilles; Robert, Alain

2015-01-01

The MICROSCOPE space mission aims at testing the Equivalence Principle (EP) with an accuracy of 10-15. This principle is one of the basis of the General Relativity theory; it states the equivalence between gravitational and inertial mass. The test is based on the precise measurement of a gravitational signal by a differential electrostatic accelerometer which includes two cylindrical test masses made of different materials. The accelerometers constitute the payload accommodated on board a drag-free micro-satellite which is controlled inertial or rotating about the normal to the orbital plane. The acceleration estimates used for the EP test are disturbed by the instruments physical parameters and by the instrument environment conditions on-board the satellite. These parameters are partially measured with ground tests or during the integration of the instrument in the satellite (alignment). Nevertheless, the ground evaluations are not sufficient with respect to the EP test accuracy objectives. An in-orbit calibration is therefore needed to characterize them finely. The calibration process for each parameter has been defined.

Theoretical investigation of the magnetoelectric properties of Bi2NiTiO6

NASA Astrophysics Data System (ADS)

Patra, Lokanath; Ravindran, P.

2018-04-01

We report the first principle investigations on the structural, electronic, magnetic and ferroelectric properties of a Pb free double perovskite multiferroic Bi2NiTiO6 using density functional theory within the general gradient approximation (GGA) and GGA+U method. Our results show that Bi2NiTiO6 will be an insulator with G-type magnetic ordering in its ground state with Ni2+ in a high spin state and a spin moment of 1.741μB. The paraelectric phase stabilizes in nonmagnetic state with Ni2+ in low spin configuration showing that spin state transition plays an important role in strong magnetoelectric coupling in Bi2NiTiO6. The bonding characteristics of the constituents are analyzed with the help of partial density of states and Born effective charges. The presence of Ti ions at Ni sites suppresses the disproportionation observed in case of BiNiO3 and results in a noncentrosymmetric crystal structure. The coexistence of Bi 6s lone pair and Ti4+ d0 ions which brings covalency produces a polarization of 32 µCcm-2.

Is the ground state of Yang-Mills theory Coulombic?

NASA Astrophysics Data System (ADS)

Heinzl, T.; Ilderton, A.; Langfeld, K.; Lavelle, M.; Lutz, W.; McMullan, D.

2008-08-01

We study trial states modelling the heavy quark-antiquark ground state in SU(2) Yang-Mills theory. A state describing the flux tube between quarks as a thin string of glue is found to be a poor description of the continuum ground state; the infinitesimal thickness of the string leads to UV artifacts which suppress the overlap with the ground state. Contrastingly, a state which surrounds the quarks with non-Abelian Coulomb fields is found to have a good overlap with the ground state for all charge separations. In fact, the overlap increases as the lattice regulator is removed. This opens up the possibility that the Coulomb state is the true ground state in the continuum limit.

Water Resources Data, Pennsylvania, Water Year 1999. Volume 3. Ohio and St. Lawrence River Basins

USGS Publications Warehouse

Siwicki, R.W.

2000-01-01

The Water Resources Division of the U.S. Geological Survey, in cooperation with State, municipal, and Federal agencies, collects a large amount of data pertaining to the water resources of Pennsylvania each water year. These data, accumulated during many water years, constitute a valuable data base for developing an improved understanding of the water resources of the State. To make these data readily available to interested parties outside the Geological Survey, these data are published annually in this report series entitled "Water Resources Data - Pennsylvania, Volumes 1, 2, and 3." Volume 1 contains data for the Delaware River Basin; Volume 2, the Susquehanna and Potomac River Basins; and Volume 3, the Ohio and St. Lawrence River Basins.This report, Volume 3, contains: (1) discharge records for 57 continuous-record streamflow-gaging stations, 5 partial-record stations, and 16 special study and miscellaneous streamflow sites; (2) elevation and contents records for 11 lakes and reservoirs; (3) water-quality records for 1 streamflow gaging station and 121 partial-record and project stations; and (4) water-level records for 15 ground-water network observation wells and. Additional water data collected at various sites not involved in the systematic data-collection program may also be presented.Publications similar to this report are published annually by the Geological Survey for all States. For the purpose of archiving, these official reports have an identification number consisting of the two-letter State abbreviation, the last two digits of the water year, and the volume number. For example, this volume is identified as "U.S. Geological Survey Water-Data Report PA-99-3." These water-data reports, beginning with the 1971 water year, are for sale as paper copy or microfiche by the National Technical Information Service, U.S. Department of Commerce, Springfield, VA 22161.The annual series of Water Data Reports for Pennsylvania began with the 1961 water-year report and contained only data relating to quantities of surface water. With the 1964 water year, a companion report (part 2) was introduced that contained only data relating to water quality. Beginning with the 1975 water year the report was changed to three volumes (by river basin), with each volume containing data on quantities of surface water, quality of surface and ground water, and ground-water levels.Prior to the introduction of this series and for several years concurrent with it, water-resources data for Pennsylvania were published in U.S. Geological Survey Water-Supply Papers. Data on stream discharge and stage, and on lake or reservoir contents and stage, through September 1960, were published annually under the title "Surface-Water Supply of the United States," which was released in numbered parts as determined by natural drainage basins. For the 1961-70 water years, these data were published in two 5-year reports. Data prior to 1961 are included in two reports: "Compilation of Records of Surface Waters of the United States through 1950," and "Compilation of Records of Surface Waters of the United States, October 1950 to September 1960." Data for Pennsylvania are published in Parts 1, 3, and 4. Data on chemical quality, temperature, and suspended sediment for the 1941-70 water years were published annually under the title "Quality of Surface Waters of the United States," and ground-water levels for the 1935-74 water years were published annually under the title "Ground-Water Levels in the United States." The above mentioned Water-Supply Papers may be consulted in the libraries of the principal cities of the United States and may be purchased from the U.S. Geological Survey, Information Services, Box 25286, Denver, CO 80225.Information for ordering specific reports may be obtained from the Pennsylvania District Office at the address on the back of the title page or by phoning the Scientific and Technical Products Section at (717) 730-6940. Information on the availability of unpublished data or statistical analyses may be obtained from the District Information Specialist (telephone (717) 730-6916) or FAX (717) 730-6997.

The Effects of Thinning on Beetles (Coleoptera: Carabidae, Cerambycidae) in Bottomland Hardwood Forests

Treesearch

Michael D. Warriner; T. Evan Nebeker; Theodor D. Leininger; James S. Meadows

2002-01-01

Abstract - The responses of two groups of beetles, ground beetles (Carabidae) and longhorned beetles (Cerambycidae), to a partial cutting technique (thinning) applied to major and minor stream bottom sites in Mississippi were examined. Species diversity of ground beetles and longhorned beetles was greater in thinned stands than unthinned stands two...

Studies of quantum dots in the quantum Hall regime

NASA Astrophysics Data System (ADS)

Goldmann, Eyal

We present two studies of quantum dots in the quantum Hall regime. In the first study, presented in Chapter 3, we investigate the edge reconstruction phenomenon believed to occur when the quantum dot filling fraction is n≲1 . Our approach involves the examination of large dots (≤40 electrons) using a partial diagonalization technique in which the occupancies of the deep interior orbitals are frozen. To interpret the results of this calculation, we evaluate the overlap between the diagonalized ground state and a set of trial wavefunctions which we call projected necklace (PN) states. A PN state is simply the angular momentum projection of a maximum density droplet surrounded by a ring of localized electrons. Our calculations reveal that PN states have up to 99% overlap with the diagonalized ground states, and are lower in energy than the states identified in Chamon and Wen's study of the edge reconstruction. In the second study, presented in Chapter 4, we investigate quantum dots in the fractional quantum Hall regime using a Hartree formulation of composite fermion theory. We find that under appropriate conditions, the chemical potential of the dots oscillates periodically with B due to the transfer of composite fermions between quasi-Landau bands. This effect is analogous the addition spectrum oscillations which occur in quantum dots in the integer quantum Hall regime. Period f0 oscillations are found in sharply confined dots with filling factors nu = 2/5 and nu = 2/3. Period 3 f0 oscillations are found in a parabolically confined nu = 2/5 dot. More generally, we argue that the oscillation period of dots with band pinning should vary continuously with B, whereas the period of dots without band pinning is f0 .

Bipartite separability and nonlocal quantum operations on graphs

NASA Astrophysics Data System (ADS)

Dutta, Supriyo; Adhikari, Bibhas; Banerjee, Subhashish; Srikanth, R.

2016-07-01

In this paper we consider the separability problem for bipartite quantum states arising from graphs. Earlier it was proved that the degree criterion is the graph-theoretic counterpart of the familiar positive partial transpose criterion for separability, although there are entangled states with positive partial transpose for which the degree criterion fails. Here we introduce the concept of partially symmetric graphs and degree symmetric graphs by using the well-known concept of partial transposition of a graph and degree criteria, respectively. Thus, we provide classes of bipartite separable states of dimension m ×n arising from partially symmetric graphs. We identify partially asymmetric graphs that lack the property of partial symmetry. We develop a combinatorial procedure to create a partially asymmetric graph from a given partially symmetric graph. We show that this combinatorial operation can act as an entanglement generator for mixed states arising from partially symmetric graphs.

Dispersion Engineering of Bose-Einstein Condensates

NASA Astrophysics Data System (ADS)

Khamehchi, Mohammad Amin

The subject of this dissertation is engineering the dispersion relation for dilute Bose-Einstein condensates (BECs). When a BEC is immersed into suitably tailored laser fields its dispersion can be strongly modified. Prominent examples for such laser fields include optical lattice geometries and Raman dressing fields. The ability to engineer the dispersion of a BEC allows for the investigation of a range of phenomena related to quantum hydrodynamics and condensed matter. In the first context, this dissertation studies the excitation spectrum of a spin-orbit coupled (SOC) BEC. The spin-orbit coupling is generated by " dressing" the atoms with two Raman laser fields. The excitation spectrum has a Roton-like feature that can be altered by tuning the Raman laser parameters. It is demonstrated that the Roton mode can be softened, but it does not reach the ground state energy for the experimental conditions we had. Furthermore, the expansion of SOC BECs in 1D is studied by relaxing the trap allowing the BEC to expand in the SOC direction. Contrary to the findings for optical lattices, it is observed that the condensate partially occupies quasimomentum states with negative effective mass, and therefore an abrupt deceleration is observed although the mean field force is along the direction of expansion. In condensed-matter systems, a periodic lattice structure often plays an important role. In this context, an alternative to the Raman dressing scheme can be realized by coupling the s- and p- bands of a static optical lattice via a weak moving lattice. The bands can be treated as pseudo-spin states. It is shown that similar to the dispersion relation of a Raman dressed SOC, the quasimomentum of the ground state is different from zero. Coherent coupling of the SOC dispersion minima can lead to the realization of the stripe phase even though it is not the thermodynamic ground state of the system. Along the lines of studying the hydrodynamics of BECs, three novel multicomponent solitonic states are realized. It is shown that the solitons are structurally stable and the oscillation of vector dark-anti-dark solitons is studied in a weak harmonic trap.

Water resources data, Iowa, water year 2001, Volume 2. surface water--Missouri River basin, and ground water

USGS Publications Warehouse

Nalley, G.M.; Gorman, J.G.; Goodrich, R.D.; Miller, V.E.; Turco, M.J.; Linhart, S.M.

2002-01-01

The Water Resources Division of the U.S. Geological Survey, in cooperation with State, county, municipal, and other Federal agencies, obtains a large amount of data pertaining to the water resources of Iowa each water year. These data, accumulated during many water years, constitute a valuable data base for developing an improved understanding of the water resources of the State. To make this data readily available to interested parties outside of the Geological Survey, the data is published annually in this report series entitled “Water Resources Data - Iowa” as part of the National Water Data System. Water resources data for water year 2001 for Iowa consists of records of stage, discharge, and water quality of streams; stage and contents of lakes and reservoirs; and water levels and water quality of ground water. This report, in two volumes, contains stage or discharge records for 132 gaging stations; stage records for 9 lakes and reservoirs; water-quality records for 4 gaging stations; sediment records for 13 gaging stations; and water levels for 163 ground-water observation wells. Also included are peak-flow data for 92 crest-stage partial-record stations, water-quality data from 86 municipal wells, and precipitation data collected at 6 gaging stations and 2 precipitation sites. Additional water data were collected at various sites not included in the systematic data-collection program, and are published here as miscellaneous measurements and analyses. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating local, State, and Federal agencies in Iowa.Records of discharge or stage of streams, and contents or stage of lakes and reservoirs were first published in a series of U.S. Geological Survey water-supply papers entitled “Surface Water Supply of the United States.” Through September 30, 1960, these water-supply papers were published in an annual series; during 1961-65 and 1966-70, they were published in 5- year series. Records of chemical quality, water temperatures, and suspended sediment were published from 1941 to 1970 in an annual series of water-supply papers entitled “Quality of Surface Waters of the United States.” Records of ground-water levels were published from 1935 to 1974 in a series of water-supply papers entitled “Ground-Water Levels in the United States.” Water-supply papers may be consulted in the libraries of the principal cities in the United States, or they may be purchased from Books and Open-File Reports Section, Federal Center, Box 25425, Denver, Colorado 80225. For water years 1961 through 1970, streamflow data were released by the Geological Survey in annual reports on a State-boundary basis. Water-quality records for water years 1964 through 1970 were similarly released either in separate reports or in conjunction with streamflow records. Beginning with the 1971 water year, water data for streamflow, water quality, and ground water is published in official U.S. Geological Survey reports on a State-boundary basis. These official reports carry an identification number consisting of the two-letter State postal abbreviation, the last two digits of the water year, and the volume number. For example, this report is identified as “U.S. Geological Survey Water-Data Report IA-01-1.” These water-data reports are for sale by the National Technical Information Service, U.S. Department of Commerce, Springfield, Virginia 22161.

Water Resources Data Ohio: Water year 1994. Volume 1, Ohio River Basin excluding Project Data

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

1994-12-31

The Water Resources Division of the US Geological Survey (USGS) in cooperation with State agencies, obtains a large amount of data each water year (a water year is the 12-month period from October 1 through September 30 and is identified by the calendar year in which it ends) pertaining to the water resources of Ohio. These data, accumulated during many years, constitute a valuable data base for developing an improved understanding of the water resources of the State. To make these data readily available to interested parties outside the USGS, they are published annually in this report series entitled ``Watermore » Resources Data--Ohio.`` This report (in two volumes) includes records on surface water and ground water in the State. Specifically, it contains: (1) Discharge records for streamflow-gaging stations, miscellaneous sites, and crest-stage stations; (2) stage and content records for streams, lakes, and reservoirs; (3) water-quality data for streamflow-gaging stations, wells, synoptic sites, and partial-record sit -aid (4) water-level data for observation wells. Locations of lake-and streamflow-gaging stations, water-quality stations, and observation wells for which data are presented in this volume are shown in figures 8a through 8b. The data in this report represent that part of the National Water Data System collected by the USGS and cooperating State and Federal agencies in Ohio. This series of annual reports for Ohio began with the 1961 water year with a report that contained only data relating to the quantities of surface water. For the 1964 water year, a similar report was introduced that contained only data relating to water quality. Beginning with the 1975 water year, the report was changed to present (in two or three volumes) data on quantities of surface water, quality of surface and ground water, and ground-water levels.« less

[Somnambulism: clinical and eletrophysiological aspects].

PubMed

Szúcs, Anna; Halász, Péter

2005-06-05

The authors review the literature on the epidemiology, the clinical and electrophysiological symptoms of somnambulism. The disorder specified as "nREM parasomnia with awakening disorder" belongs to the nREM sleep (awakening) parasomnias. In most of the cases its occurence is familial with the highest prevalence at age 12 year. Above age 12 year most cases recover whereas 6% of prevalence is reported in adults. It is probable that most patients seek medical help only in severe cases associated with injuries, accidents or violence. Its etiology is unknown; in essence it is a sleep regulation disorder characterised by a dissociated state of partial awakening from nREM sleep: the motor system becomes awake while consciousness remains clouded. There are several medicines inducing somnambulism in patients otherwise free from this disorder. In somnambule patients the most important provoking factors are sleep deprivation as well as pathological states and circumstances evoking sleep loss. Somnambulism should be differentiated from complex partial epileptic seizures and REM behaviour disorder. As there is no specific treatment at the moment it is important to assure safe sleeping circumstances - ground flour, closed windows, and no fragile furniture. Clonazepam and selective serotonin reuptake inhibitors prove sometimes effective, but the most effective methods in decreasing the frequency of somnambule episodes are the regular sleep-wakefulness schedule and the avoidance of sleep deprivation.

Controlled Teleportation of a Qudit State by Partially Entangled GHZ States

NASA Astrophysics Data System (ADS)

Wang, Jin-wei; Shu, Lan; Mo, Zhi-wen; Zhang, Zhi-hua

2014-08-01

In this paper, we propose a controlled teleportation scheme which communicates an arbitrary ququart state via two sets of partially entangled GHZ state. The necessary measurements and operations are given detailedly. Furthmore the scheme is generalized to teleport a qudit state via s sets of partially entangled GHZ state.

Management of ground water and evolving hydrogeologic studies in New Jersey : a heavily urbanized and industrialized state in the northeastern United States

USGS Publications Warehouse

Leahy, P. Patrick

1985-01-01

New Jersey is the most densely populated and one of the most industrialized states in the United States. An abundance of freshwater and proximity to major northeastern metropolitan centers has facilitated this development. Pumpage of freshwater from all aquifers in the State in 1980 was 730 million gallons per day (2.76 million cubic meters per day).Management and efficient development of the ground-water resources of the State are the responsibility of the New Jersey Department of Environmental Protection. Laws have been enacted and updated by the State legislature to manage water allocation and to control the disposal of hazardous wastes. Present resource management is guided by the New Jersey Water-Supply Master Plan of 1981. Funding for management activities is partially derived from the sale of state-approved bonds.Effective planning and regional management require accurate and up-to-date hydrologic information and analyses. The U.S. Geological Survey, in cooperation with the New Jersey Geological Survey, is conducting three intensive ground-water studies involving the collection and interpretation of hydrologic data to meet the urgent water-management needs of New Jersey. These studies are part of a long-term cooperative program and are funded through the Water-Supply Bond Act of 1981. They began in 1983 and are scheduled to be completed in 1988.The project areas are situated in the New Jersey part of the Atlantic Coastal Plain in and near Atlantic City, Camden, and South River. They range in size from 400 to 1,200 mil (1,040 to 3,120 km2). The studies are designed to define the geology, hydrology, and geochemistry of the local ground-water systems. The results of these studies will enable the State to address more effectively major problems in these areas such as declining water levels, overpumping, saltwater intrusion, and ground-water contamination resulting from the improper disposal of hazardous wastes.Specific objectives of these studies by the U.S. Geological Survey are to (1) develop an accurate and up-to-date hydrogeologic data base, (2) design and implement a data-collection program and establish a computerized information management system, (3) refine the conceptualization of the ground-water flow system, and (4) define the geochemistry of the aquifer system by conducting a water-quality appraisal. The objectives are accomplished by standard hydrogeologic methods. Information concerning hydrogeologic framework, ground-water levels, water use, hydraulic characteristics, and water quality in the study areas is compiled from all available sources. Additional data needed are collected through well inventories, surface geophysical surveys, water-quality samplings, water-level measurements, and a well-drilling program.Interpretation of the flow system is based on the use of standard analytical techniques and digital flow modeling. Calibrated flow models will provide ground-water managers with a mechanism to develop and test regional water-supply strategies.Definition of the geochemistry of the aquifer system is accomplished through a variety of methods which depend on the problems and available data in the particular study area. The approach includes statistical analysis of water-quality data, reaction-path modeling, and determination of the movement of chemical constituents using analytical and numerical modeling techniques.A combined staff of 25 to 30 professionals and technicians from the New Jersey District office of the U.S. Geological Survey is committed to the three studies. The staff has specialists in geohydrology, numerical modeling, geochemistry, geophysics, and computer science. The findings of these studies will be published in data reports, interpretive reports, instructional manuals and journal articles.

Behavior of ground vegetation under a partially cut stand of Douglas-fir.

Treesearch

Kenneth W. Krueger

1960-01-01

Environmental changes resulting from logging in the Douglas-fir region often create ideal growing conditions for many woody and herbaceous plants. A rapid increase of brush and low vegetation, in turn, can seriously hinder efforts to establish a new stand. Consequently, one argument against partial cutting in Douglas-fir (Pseudotsuga menziesii) is...

Partial Automated Alignment and Integration System

NASA Technical Reports Server (NTRS)

Kelley, Gary Wayne (Inventor)

2014-01-01

The present invention is a Partial Automated Alignment and Integration System (PAAIS) used to automate the alignment and integration of space vehicle components. A PAAIS includes ground support apparatuses, a track assembly with a plurality of energy-emitting components and an energy-receiving component containing a plurality of energy-receiving surfaces. Communication components and processors allow communication and feedback through PAAIS.

First-principles theory of cation and intercalation ordering in Li xCoO 2

NASA Astrophysics Data System (ADS)

Wolverton, C.; Zunger, Alex

Several types of cation- and vacancy-ordering are of interest in the Li xCoO 2 battery cathode material since they can have a profound effect on the battery voltage. We present a first-principles theoretical approach which can be used to calculate both cation- and vacancy-ordering patterns at both zero and finite temperatures. This theory also provides quantum-mechanical predictions (i.e., without the use of any experimental input) of battery voltages of both ordered and disordered Li xCoO 2/Li cells from the energetics of the Li intercalation reactions. Our calculations allow us to search the entire configurational space to predict the lowest-energy ground-state structures, search for large voltage cathodes, explore metastable low-energy states, and extend our calculations to finite temperatures, thereby searching for order-disorder transitions and states of partial disorder. We present the first prediction of the stable spinel structure LiCo 2O 4 for the 50% delithiated Li 0.5CoO 2.

Effective chiral restoration in the ρ' meson in lattice QCD

NASA Astrophysics Data System (ADS)

Glozman, L. Ya.; Lang, C. B.; Limmer, Markus

2010-11-01

In simulations with dynamical quarks it has been established that the ground state ρ in the infrared is a strong mixture of the two chiral representations (0,1)+(1,0) and (1/2,1/2)b. Its angular momentum content is approximately the S13 partial wave. Effective chiral restoration in an excited ρ-meson would require that in the infrared this meson couples predominantly to one of the two representations. The variational method allows one to study the mixing of interpolators with different chiral transformation properties in the nonperturbatively determined excited state at different resolution scales. We present results for the first excited state of the ρ-meson using simulations with nf=2 dynamical quarks. We point out, that in the infrared a leading contribution to ρ'=ρ(1450) comes from (1/2,1/2)b, in contrast to the ρ. The ρ' wave function contains a significant contribution of the D13 wave which is not consistent with the quark model prediction.

Towards zero-threshold optical gain using charged semiconductor quantum dots

DOE PAGES

Wu, Kaifeng; Park, Young -Shin; Lim, Jaehoon; ...

2017-10-16

Colloidal semiconductor quantum dots are attractive materials for the realization of solution-processable lasers. However, their applications as optical-gain media are complicated by a non-unity degeneracy of band-edge states, because of which multiexcitons are required to achieve the lasing regime. This increases the lasing thresholds and leads to very short optical gain lifetimes limited by nonradiative Auger recombination. Here, we show that these problems can be at least partially resolved by employing not neutral but negatively charged quantum dots. By applying photodoping to specially engineered quantum dots with impeded Auger decay, we demonstrate a considerable reduction of the optical gain thresholdmore » due to suppression of ground-state absorption by pre-existing carriers. Moreover, by injecting approximately one electron per dot on average, we achieve a more than twofold reduction in the amplified spontaneous emission threshold, bringing it to the sub-single-exciton level. Furthermore, these measurements indicate the feasibility of ‘zero-threshold’ gain achievable by completely blocking the band-edge state with two electrons.« less

Towards zero-threshold optical gain using charged semiconductor quantum dots

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wu, Kaifeng; Park, Young -Shin; Lim, Jaehoon

Colloidal semiconductor quantum dots are attractive materials for the realization of solution-processable lasers. However, their applications as optical-gain media are complicated by a non-unity degeneracy of band-edge states, because of which multiexcitons are required to achieve the lasing regime. This increases the lasing thresholds and leads to very short optical gain lifetimes limited by nonradiative Auger recombination. Here, we show that these problems can be at least partially resolved by employing not neutral but negatively charged quantum dots. By applying photodoping to specially engineered quantum dots with impeded Auger decay, we demonstrate a considerable reduction of the optical gain thresholdmore » due to suppression of ground-state absorption by pre-existing carriers. Moreover, by injecting approximately one electron per dot on average, we achieve a more than twofold reduction in the amplified spontaneous emission threshold, bringing it to the sub-single-exciton level. Furthermore, these measurements indicate the feasibility of ‘zero-threshold’ gain achievable by completely blocking the band-edge state with two electrons.« less

Dendrimer-magnetic nanostructure: a Monte Carlo simulation

NASA Astrophysics Data System (ADS)

Jabar, A.; Masrour, R.

2017-11-01

In this paper, the magnetic properties of ternary mixed spins (σ,S,q) Ising model on a dendrimer nanostructure are studied using Monte Carlo simulations. The ground state phase diagrams of dendrimer nanostructure with ternary mixed spins σ = 1/2, S = 1 and q = 3/2 Ising model are found. The variation of the thermal total and partial magnetizations with the different exchange interactions, the external magnetic fields and the crystal fields have been also studied. The reduced critical temperatures have been deduced. The magnetic hysteresis cycles have been discussed. In particular, the corresponding magnetic coercive filed values have been deduced. The multiples hysteresis cycles are found. The dendrimer nanostructure has several applications in the medicine.

Chiral effective-field theory of the nucleon spin structure

NASA Astrophysics Data System (ADS)

Pascalutsa, Vladimir

2017-01-01

I will review the recent chiral EFT calculations of the nucleon (spin) structure functions at low Q2, confronted with the Jefferson Lab measurements. The moments of the structure functions correspond with various polarizabilities, and I will explain why one of them - δLT - is especially interesting. I will also discuss how the spin structure functions at low Q enter in the atomic calculations of the hyperfine splittings and how they are impacting the ongoing experimental program at PSI (Switzerland) to measure the ground-state hyperfine splitting of muonic hydrogen. Partially supported by the Deutsche Forschungsgemeinschaft (DFG) through the Collaborative Research Center SFB 1044 [The Low-Energy Frontier of the Standard Model].

Ultracold collisions between Rb atoms and a Sr+ ion

NASA Astrophysics Data System (ADS)

Meir, Ziv; Sikorsky, Tomas; Ben-Shlomi, Ruti; Dallal, Yehonatan; Ozeri, Roee

2015-05-01

In last decade, a novel field emerged, in which ultracold atoms and ions in overlapping traps are brought into interaction. In contrast to the short ranged atom-atom interaction which scales as r-6, atom-ion potential persists for hundreds of μm's due to its lower power-law scaling - r-4. Inelastic collisions between the consistuents lead to spin and charge transfer and also to molecule formation. Elastic collisions control the energy transfer between the ion and the atoms. The study of collisions at the μK range has thus far been impeded by the effect of the ion's micromotion which limited collision energy to mK scale. Unraveling this limit will allow to investigate few partial wave and even S-wave collisions. Our system is capable of trapping Sr+ ions and Rb and Sr atoms and cooling them to their quantum ground state. Atoms and ions are trapped and cooled in separate chambers. Then, the atoms are transported using an optical conveyer belt to overlap the ions. In contrast to other experiments in this field where the atoms are used to sympathetic cool the ion, our system is also capable of ground state cooling the ion before immersing it into the atom cloud. By this method, we would be able to explore heating and cooling dynamics in the ultracold regime.

Ground-state splitting of ultrashallow thermal donors with negative central-cell corrections in silicon

NASA Astrophysics Data System (ADS)

Hara, Akito; Awano, Teruyoshi

2017-06-01

Ultrashallow thermal donors (USTDs), which consist of light element impurities such as carbon, hydrogen, and oxygen, have been found in Czochralski silicon (CZ Si) crystals. To the best of our knowledge, these are the shallowest hydrogen-like donors with negative central-cell corrections in Si. We observed the ground-state splitting of USTDs by far-infrared optical absorption at different temperatures. The upper ground-state levels are approximately 4 meV higher than the ground-state levels. This energy level splitting is also consistent with that obtained by thermal excitation from the ground state to the upper ground state. This is direct evidence that the wave function of the USTD ground state is made up of a linear combination of conduction band minimums.

Sun-Direction Estimation Using a Partially Underdetermined Set of Coarse Sun Sensors

NASA Astrophysics Data System (ADS)

O'Keefe, Stephen A.; Schaub, Hanspeter

2015-09-01

A comparison of different methods to estimate the sun-direction vector using a partially underdetermined set of cosine-type coarse sun sensors (CSS), while simultaneously controlling the attitude towards a power-positive orientation, is presented. CSS are commonly used in performing power-positive sun-pointing and are attractive due to their relative inexpensiveness, small size, and reduced power consumption. For this study only CSS and rate gyro measurements are available, and the sensor configuration does not provide global triple coverage required for a unique sun-direction calculation. The methods investigated include a vector average method, a combination of least squares and minimum norm criteria, and an extended Kalman filter approach. All cases are formulated such that precise ground calibration of the CSS is not required. Despite significant biases in the state dynamics and measurement models, Monte Carlo simulations show that an extended Kalman filter approach, despite the underdetermined sensor coverage, can provide degree-level accuracy of the sun-direction vector both with and without a control algorithm running simultaneously. If no rate gyro measurements are available, and rates are partially estimated from CSS, the EKF performance degrades as expected, but is still able to achieve better than 10∘ accuracy using only CSS measurements.

Spreading dynamics on complex networks: a general stochastic approach.

PubMed

Noël, Pierre-André; Allard, Antoine; Hébert-Dufresne, Laurent; Marceau, Vincent; Dubé, Louis J

2014-12-01

Dynamics on networks is considered from the perspective of Markov stochastic processes. We partially describe the state of the system through network motifs and infer any missing data using the available information. This versatile approach is especially well adapted for modelling spreading processes and/or population dynamics. In particular, the generality of our framework and the fact that its assumptions are explicitly stated suggests that it could be used as a common ground for comparing existing epidemics models too complex for direct comparison, such as agent-based computer simulations. We provide many examples for the special cases of susceptible-infectious-susceptible and susceptible-infectious-removed dynamics (e.g., epidemics propagation) and we observe multiple situations where accurate results may be obtained at low computational cost. Our perspective reveals a subtle balance between the complex requirements of a realistic model and its basic assumptions.

Spin-dependent analysis of two-dimensional electron liquids

NASA Astrophysics Data System (ADS)

Bulutay, C.; Tanatar, B.

2002-05-01

Two-dimensional electron liquid (2D EL) at full Fermi degeneracy is revisited, giving special attention to the spin-polarization effects. First, we extend the recently proposed classical-map hypernetted-chain (CHNC) technique to the 2D EL, while preserving the simplicity of the original proposal. An efficient implementation of CHNC is given utilizing Lado's quadrature expressions for the isotropic Fourier transforms. Our results indicate that the paramagnetic phase stays to be the ground state until the Wigner crystallization density, even though the energy separation with the ferromagnetic and other partially polarized states become minute. We analyze compressibility and spin stiffness variations with respect to density and spin polarization, the latter being overlooked until now. Spin-dependent static structure factor and pair-distribution functions are computed; agreement with the available quantum Monte Carlo data persists even in the strong-coupling regime of the 2D EL.

Charge-transfer crystallites as molecular electrical dopants

PubMed Central

Méndez, Henry; Heimel, Georg; Winkler, Stefanie; Frisch, Johannes; Opitz, Andreas; Sauer, Katrein; Wegner, Berthold; Oehzelt, Martin; Röthel, Christian; Duhm, Steffen; Többens, Daniel; Koch, Norbert; Salzmann, Ingo

2015-01-01

Ground-state integer charge transfer is commonly regarded as the basic mechanism of molecular electrical doping in both, conjugated polymers and oligomers. Here, we demonstrate that fundamentally different processes can occur in the two types of organic semiconductors instead. Using complementary experimental techniques supported by theory, we contrast a polythiophene, where molecular p-doping leads to integer charge transfer reportedly localized to one quaterthiophene backbone segment, to the quaterthiophene oligomer itself. Despite a comparable relative increase in conductivity, we observe only partial charge transfer for the latter. In contrast to the parent polymer, pronounced intermolecular frontier-orbital hybridization of oligomer and dopant in 1:1 mixed-stack co-crystallites leads to the emergence of empty electronic states within the energy gap of the surrounding quaterthiophene matrix. It is their Fermi–Dirac occupation that yields mobile charge carriers and, therefore, the co-crystallites—rather than individual acceptor molecules—should be regarded as the dopants in such systems. PMID:26440403

Breakdown of Magnetic Order in the Pressurized Kitaev Iridate β -Li2IrO3

NASA Astrophysics Data System (ADS)

Majumder, M.; Manna, R. S.; Simutis, G.; Orain, J. C.; Dey, T.; Freund, F.; Jesche, A.; Khasanov, R.; Biswas, P. K.; Bykova, E.; Dubrovinskaia, N.; Dubrovinsky, L. S.; Yadav, R.; Hozoi, L.; Nishimoto, S.; Tsirlin, A. A.; Gegenwart, P.

2018-06-01

Temperature-pressure phase diagram of the Kitaev hyperhoneycomb iridate β -Li2IrO3 is explored using magnetization, thermal expansion, magnetostriction, and muon spin rotation measurements, as well as single-crystal x-ray diffraction under pressure and ab initio calculations. The Néel temperature of β -Li2IrO3 increases with the slope of 0.9 K /GPa upon initial compression, but the reduction in the polarization field Hc reflects a growing instability of the incommensurate order. At 1.4 GPa, the ordered state breaks down upon a first-order transition, giving way to a new ground state marked by the coexistence of dynamically correlated and frozen spins. This partial freezing in the absence of any conspicuous structural defects may indicate the classical nature of the resulting pressure-induced spin liquid, an observation paralleled to the increase in the nearest-neighbor off-diagonal exchange Γ under pressure.

An economical semi-analytical orbit theory for micro-computer applications

NASA Technical Reports Server (NTRS)

Gordon, R. A.

1988-01-01

An economical algorithm is presented for predicting the position of a satellite perturbed by drag and zonal harmonics J sub 2 through J sub 4. Simplicity being of the essence, drag is modeled as a secular decay rate in the semi-axis (retarded motion); with the zonal perturbations modeled from a modified version of the Brouwers formulas. The algorithm is developed as: an alternative on-board orbit predictor; a back up propagator requiring low energy consumption; or a ground based propagator for microcomputer applications (e.g., at the foot of an antenna). An O(J sub 2) secular retarded state partial matrix (matrizant) is also given to employ with state estimation. The theory was implemented in BASIC on an inexpensive microcomputer, the program occupying under 8K bytes of memory. Simulated trajectory data and real tracking data are employed to illustrate the theory's ability to accurately accommodate oblateness and drag effects.

An economical semi-analytical orbit theory for micro-computer applications

NASA Technical Reports Server (NTRS)

Gordon, R. A.

1986-01-01

An economical algorithm is presented for predicting the position of a satellite perturbed by drag and zonal harmonics J2 through J4. Simplicity being of the essence, drag is modeled as a secular decay rate in the semimajor axis (retarded motion) with the zonal perturbations modeled from a modified version of Brouwers formulas. The algorithm is developed as an alternative on-board orbit predictor; a back up propagator requiring low energy consumption; or a ground based propagator for microcomputer applications (e.g., at the foot of an antenna). An O(J2) secular retarded state partial matrix (matrizant) is also given to employ with state estimation. The theory has been implemented in BASIC on an inexpensive microcomputer, the program occupying under 8K bytes of memory. Simulated trajectory data and real tracking data are employed to illustrate the theory's ability to accurately accommodate oblateness and drag effects.

Absence of metastable states in strained monoatomic cubic crystals.

NASA Astrophysics Data System (ADS)

Aguayo, Aarón; Mehl, Michael L.; de Coss, Romeo

2005-03-01

The Bain path distortion of a metal with an fcc (bcc) ground state toward the bcc (fcc) structure initially requires an increase in energy, but at some point along the Bain path the energy will again decrease until a local minimum is reached. We have studied the tetragonal distortion (Bain path) of monoatomic cubic crystals, using a combination of parametrized tight-binding and first-principles linearized augmented plane wave calculations. We show that this local minimum is unstable with respect to an elastic distortion, except in the rare case that the minimum is at the bcc (fcc) point on the Bain path. This shows that body-centered-tetragonal phases of these materials, which have been seen in epitaxially grown thin films, must be stabilized by the substrate and cannot be freestanding films. This work was partially supported by Consejo Nacional de Ciencia y Tecnolog'ia (CONACYT, M'exico) under Grant No. 43830-F.

Entropy of the Bose-Einstein-condensate ground state: Correlation versus ground-state entropy

NASA Astrophysics Data System (ADS)

Kim, Moochan B.; Svidzinsky, Anatoly; Agarwal, Girish S.; Scully, Marlan O.

2018-01-01

Calculation of the entropy of an ideal Bose-Einstein condensate (BEC) in a three-dimensional trap reveals unusual, previously unrecognized, features of the canonical ensemble. It is found that, for any temperature, the entropy of the Bose gas is equal to the entropy of the excited particles although the entropy of the particles in the ground state is nonzero. We explain this by considering the correlations between the ground-state particles and particles in the excited states. These correlations lead to a correlation entropy which is exactly equal to the contribution from the ground state. The correlations themselves arise from the fact that we have a fixed number of particles obeying quantum statistics. We present results for correlation functions between the ground and excited states in a Bose gas, so as to clarify the role of fluctuations in the system. We also report the sub-Poissonian nature of the ground-state fluctuations.

Ground-state densities from the Rayleigh-Ritz variation principle and from density-functional theory.

PubMed

Kvaal, Simen; Helgaker, Trygve

2015-11-14

The relationship between the densities of ground-state wave functions (i.e., the minimizers of the Rayleigh-Ritz variation principle) and the ground-state densities in density-functional theory (i.e., the minimizers of the Hohenberg-Kohn variation principle) is studied within the framework of convex conjugation, in a generic setting covering molecular systems, solid-state systems, and more. Having introduced admissible density functionals as functionals that produce the exact ground-state energy for a given external potential by minimizing over densities in the Hohenberg-Kohn variation principle, necessary and sufficient conditions on such functionals are established to ensure that the Rayleigh-Ritz ground-state densities and the Hohenberg-Kohn ground-state densities are identical. We apply the results to molecular systems in the Born-Oppenheimer approximation. For any given potential v ∈ L(3/2)(ℝ(3)) + L(∞)(ℝ(3)), we establish a one-to-one correspondence between the mixed ground-state densities of the Rayleigh-Ritz variation principle and the mixed ground-state densities of the Hohenberg-Kohn variation principle when the Lieb density-matrix constrained-search universal density functional is taken as the admissible functional. A similar one-to-one correspondence is established between the pure ground-state densities of the Rayleigh-Ritz variation principle and the pure ground-state densities obtained using the Hohenberg-Kohn variation principle with the Levy-Lieb pure-state constrained-search functional. In other words, all physical ground-state densities (pure or mixed) are recovered with these functionals and no false densities (i.e., minimizing densities that are not physical) exist. The importance of topology (i.e., choice of Banach space of densities and potentials) is emphasized and illustrated. The relevance of these results for current-density-functional theory is examined.

Partially entangled states bridge in quantum teleportation

NASA Astrophysics Data System (ADS)

Cai, Xiao-Fei; Yu, Xu-Tao; Shi, Li-Hui; Zhang, Zai-Chen

2014-10-01

The traditional method for information transfer in a quantum communication system using partially entangled state resource is quantum distillation or direct teleportation. In order to reduce the waiting time cost in hop-by-hop transmission and execute independently in each node, we propose a quantum bridging method with partially entangled states to teleport quantum states from source node to destination node. We also prove that the designed specific quantum bridging circuit is feasible for partially entangled states teleportation across multiple intermediate nodes. Compared to two traditional ways, our partially entanglement quantum bridging method uses simpler logic gates, has better security, and can be used in less quantum resource situation.

Strain stabilization and thickness dependence of magnetism in epitaxial transition metal monosilicide thin films on Si(111)

NASA Astrophysics Data System (ADS)

Geisler, Benjamin; Kratzer, Peter

2013-09-01

We present a comprehensive study of different 3d transition metal monosilicides in their ground state crystal structure (B20), ranging from equilibrium bulk over biaxially strained bulk to epitaxial thin films on Si(111), by means of density functional theory. The magnetic properties of MnSi and FeSi films are found to be considerably modified due to the epitaxial strain induced by the substrate. In MnSi bulk material, which can be seen as a limit of thick films, we find a strain-induced volume expansion, an increase of the magnetic moments, and a significant rise of the energy difference between different spin configurations. The latter can be associated with an increase of the Curie temperature, which is in accordance with recent experimental results. While a ferromagnetic spin alignment is found to be the ground state also for ultrathin films, we show that for films of intermediate thickness a partially compensating magnetic ordering is more favorable; however, the films retain a net magnetic moment. Furthermore, we analyze the orbital structure in FeSi around the band gap, which can be located somewhere in the density of states for all studied B20 transition metal monosilicides, and find that FeSi becomes metallic and ferromagnetic under epitaxial strain. Finally, the influence of on-site electronic correlation and the reliability of ab initio calculations for 3d transition metal monosilicides are discussed.

Sound Radiation from a Supersonic Jet Passing Through a Partially Open Exhaust Duct

NASA Technical Reports Server (NTRS)

Kandula, Max

2011-01-01

The radiation of sound from a perfectly expanded Mach 2.5 cold supersonic jet of 25.4 mm exit diameter flowing through a partially open rigid-walled duct with an upstream i-deflector has been studied experimentally. In the experiments, the nozzle is mounted vertically, with the nozzle exit plane at a height of 73 jet diameters above ground level. Relative to the nozzle exit plane (NEP), the location of the duct inlet is varied at 10, 5, and -1 jet diameters. Far-field sound pressure levels were obtained at 54 jet diameters above ground with the aid of acoustic sensors equally spaced around a circular arc of radius equal to 80 jet diameters from the jet axis. Data on the jet acoustic field for the partially open duct were obtained and compared with those with a free jet and with a closed duct. The results suggest that for the partially open duct the overall sound pressure level (OASPL) decreases as the distance between the NEP and the duct inlet plane decreases, while the opposite trend is observed for the closed duct. It is also concluded that the observed peak frequency in the partially open duct increases above the free jet value as the angle from the duct axis is increased, and as the duct inlet plane becomes closer to the NEP.

Small RNA Sequencing Reveals Dlk1-Dio3 Locus-Embedded MicroRNAs as Major Drivers of Ground-State Pluripotency.

PubMed

Moradi, Sharif; Sharifi-Zarchi, Ali; Ahmadi, Amirhossein; Mollamohammadi, Sepideh; Stubenvoll, Alexander; Günther, Stefan; Salekdeh, Ghasem Hosseini; Asgari, Sassan; Braun, Thomas; Baharvand, Hossein

2017-12-12

Ground-state pluripotency is a cell state in which pluripotency is established and maintained through efficient repression of endogenous differentiation pathways. Self-renewal and pluripotency of embryonic stem cells (ESCs) are influenced by ESC-associated microRNAs (miRNAs). Here, we provide a comprehensive assessment of the "miRNome" of ESCs cultured under conditions favoring ground-state pluripotency. We found that ground-state ESCs express a distinct set of miRNAs compared with ESCs grown in serum. Interestingly, most "ground-state miRNAs" are encoded by an imprinted region on chromosome 12 within the Dlk1-Dio3 locus. Functional analysis revealed that ground-state miRNAs embedded in the Dlk1-Dio3 locus (miR-541-5p, miR-410-3p, and miR-381-3p) promoted pluripotency via inhibition of multi-lineage differentiation and stimulation of self-renewal. Overall, our results demonstrate that ground-state pluripotency is associated with a unique miRNA signature, which supports ground-state self-renewal by suppressing differentiation. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

Ground water investigations in Utah to June 30, 1936: A part of Chapter 8 in Twentieth biennial report of the State Engineer to the governor of Utah: 1935-1936

USGS Publications Warehouse

Taylor, G.H.; Thomas, H.E.

1936-01-01

During the past few years of drouth the importance of ground-water supplies has become more fully appreciated. During this time, because of subnormal replenishment of the ground-water reservoirs and the increased withdrawals from wells, the ground-water levels have declined in most developed areas in the State, a condition which has made the well owners acutely aware that ground water is not inexhaustible. Numerous cases of contention between well owners resulted in increased demands for adequate regulation of the appropriation and use of ground water. Realizing that more information concerning the ground water of the State was imperative, not only to administer the ground-water regulations but to prepare for the conservation and replenishment of existing supplies and development of new supplies, the State Legislature enacted, during its 1935 session, Senate Bill 206, which authorized the State Engineer to make an investigation of the ground water of the State. To provide for the expenses of the investigation, the bill allotted /$10,000 to the State Engineer, this sum to be matched by a State or Federal organization, and the investigation to be carried out co-operatively during the biennium beginning July 1, 1935. A co-operative agreement between the State Engineer and the United States Geological Survey was made on July 1, 1935.

Multi-year comparisons of ground-based and space-borne Fourier transform spectrometers in the high Arctic between 2006 and 2013

NASA Astrophysics Data System (ADS)

Griffin, Debora; Walker, Kaley A.; Conway, Stephanie; Kolonjari, Felicia; Strong, Kimberly; Batchelor, Rebecca; Boone, Chris D.; Dan, Lin; Drummond, James R.; Fogal, Pierre F.; Fu, Dejian; Lindenmaier, Rodica; Manney, Gloria L.; Weaver, Dan

2017-09-01

This paper presents 8 years (2006-2013) of measurements obtained from Fourier transform spectrometers (FTSs) in the high Arctic at the Polar Environment Atmospheric Research Laboratory (PEARL; 80.05° N, 86.42° W). These measurements were taken as part of the Canadian Arctic ACE (Atmospheric Chemistry Experiment) validation campaigns that have been carried out since 2004 during the polar sunrise period (from mid-February to mid-April). Each spring, two ground-based FTSs were used to measure total and partial columns of HF, O3, and trace gases that impact O3 depletion, namely, HCl and HNO3. Additionally, some tropospheric greenhouse gases and pollutant species were measured, namely CH4, N2O, CO, and C2H6. During the same time period, the satellite-based ACE-FTS made measurements near Eureka and provided profiles of the same trace gases. Comparisons have been carried out between the measurements from the Portable Atmospheric Research Interferometric Spectrometer for the InfraRed (PARIS-IR) and the co-located high-resolution Bruker 125HR FTS, as well as with the latest version of the ACE-FTS retrievals (v3.5). The total column comparison between the two co-located ground-based FTSs, PARIS-IR and Bruker 125HR, found very good agreement for most of these species (except HF), with differences well below the estimated uncertainties ( ≤ 6  %) and with high correlations (R ≥ 0. 8). Partial columns have been used for the ground-based to space-borne comparison, with coincident measurements selected based on time, distance, and scaled potential vorticity (sPV). The comparisons of the ground-based measurements with ACE-FTS show good agreement in the partial columns for most species within 6  % (except for C2H6 and PARIS-IR HF), which is consistent with the total retrieval uncertainty of the ground-based instruments. The correlation coefficients (R) of the partial column comparisons for all eight species range from approximately 0.75 to 0.95. The comparisons show no notable increases of the mean differences over these 8 years, indicating the consistency of these datasets and suggesting that the space-borne ACE-FTS measurements have been stable over this period. In addition, changes in the amounts of these trace gases during springtime between 2006 and 2013 are presented and discussed. Increased O3 (0. 9  %  yr-1), HCl (1. 7  %  yr-1), HF (3. 8  %  yr-1), CH4 (0.5  % yr-1), and C2H6 (2. 3 % yr-1, 2009-2013) have been found with the PARIS-IR dataset, the longer of the two ground-based records.

Improving the efficiency of single and multiple teleportation protocols based on the direct use of partially entangled states

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fortes, Raphael; Rigolin, Gustavo, E-mail: rigolin@ifi.unicamp.br

We push the limits of the direct use of partially pure entangled states to perform quantum teleportation by presenting several protocols in many different scenarios that achieve the optimal efficiency possible. We review and put in a single formalism the three major strategies known to date that allow one to use partially entangled states for direct quantum teleportation (no distillation strategies permitted) and compare their efficiencies in real world implementations. We show how one can improve the efficiency of many direct teleportation protocols by combining these techniques. We then develop new teleportation protocols employing multipartite partially entangled states. The threemore » techniques are also used here in order to achieve the highest efficiency possible. Finally, we prove the upper bound for the optimal success rate for protocols based on partially entangled Bell states and show that some of the protocols here developed achieve such a bound. -- Highlights: •Optimal direct teleportation protocols using directly partially entangled states. •We put in a single formalism all strategies of direct teleportation. •We extend these techniques for multipartite partially entangle states. •We give upper bounds for the optimal efficiency of these protocols.« less

Surface- and ground-water relations on the Portneuf river, and temporal changes in ground-water levels in the Portneuf Valley, Caribou and Bannock Counties, Idaho, 2001-02

USGS Publications Warehouse

Barton, Gary J.

2004-01-01

The State of Idaho and local water users are concerned that streamflow depletion in the Portneuf River in Caribou and Bannock Counties is linked to ground-water withdrawals for irrigated agriculture. A year-long field study during 2001 02 that focused on monitoring surface- and ground-water relations was conducted, in cooperation with the Idaho Department of Water Resources, to address some of the water-user concerns. The study area comprised a 10.2-mile reach of the Portneuf River downstream from the Chesterfield Reservoir in the broad Portneuf Valley (Portneuf River Valley reach) and a 20-mile reach of the Portneuf River in a narrow valley downstream from the Portneuf Valley (Pebble-Topaz reach). During the field study, the surface- and ground-water relations were dynamic. A losing river reach was delineated in the middle of the Portneuf River Valley reach, centered approximately 7.2 miles downstream from Chesterfield Reservoir. Two seepage studies conducted in the Portneuf Valley during regulated high flows showed that the length of the losing river reach increased from 2.6 to nearly 6 miles as the irrigation season progressed.Surface- and ground-water relations in the Portneuf Valley also were characterized from an analysis of specific conductance and temperature measurements. In a gaining reach, stratification of specific conductance and temperature across the channel of the Portneuf River was an indicator of ground water seeping into the river.An evolving method of using heat as a tracer to monitor surface- and ground-water relations was successfully conducted with thermistor arrays at four locations. Heat tracing monitored a gaining reach, where ground water was seeping into the river, and monitored a losing reach, where surface water was seeping down through the riverbed (also referred to as a conveyance loss), at two locations.Conveyance losses in the Portneuf River Valley reach were greatest, about 20 cubic feet per second, during the mid-summer regulated high flows. Conveyance losses in the Pebble-Topaz reach were greatest, about 283 cubic feet per second, during the spring regulated high flows and were attributed to a hydroelectric project.Comparison of water levels in 30 wells in the Portneuf Valley during September and October 1968 and 2001 indicated long-term declines since 1968; the median decline was 3.4 feet. September and October were selected for characterizing long-term ground-water-level fluctuations because declines associated with irrigation reach a maximum at the end of the irrigation season. The average annual snowpack in the study area has declined significantly; 1945 85 average annual snowpack was 16.1 inches, whereas 1986 through 2002 average annual snowpack was 11.6 inches. Water-level declines during 1998 2002 may be partially attributable to the extended dry climatic conditions. It is unclear whether the declines could be partially attributed to increases in ground-water withdrawals. Between 1968 and 1980, water rights for ground-water withdrawals nearly doubled from 23,500 to 46,000 acre-feet per year. During this period, ground-water levels were relatively constant and did not exhibit a declining trend that could be related to increased ground-water withdrawal rights. However, ground-water withdrawals are not measured in the valley; thus, the amount of water pumped is not known. Since the 1990s, there have been several years when the Chesterfield Reservoir has not completely refilled, and the water in storage behind the reservoir has been depleted by the middle of the irrigation season. In this situation, surface-water diversions for irrigation were terminated before the end of the irrigation season, and irrigators, who were relying in part on diversions from the Portneuf River, had to rely solely on ground water as an alternate supply. Smaller volumes of water in the Chesterfield Reservoir since the 1990s indicate a growing demand for ground-water supplies.

Classical many-particle systems with unique disordered ground states

NASA Astrophysics Data System (ADS)

Zhang, G.; Stillinger, F. H.; Torquato, S.

2017-10-01

Classical ground states (global energy-minimizing configurations) of many-particle systems are typically unique crystalline structures, implying zero enumeration entropy of distinct patterns (aside from trivial symmetry operations). By contrast, the few previously known disordered classical ground states of many-particle systems are all high-entropy (highly degenerate) states. Here we show computationally that our recently proposed "perfect-glass" many-particle model [Sci. Rep. 6, 36963 (2016), 10.1038/srep36963] possesses disordered classical ground states with a zero entropy: a highly counterintuitive situation . For all of the system sizes, parameters, and space dimensions that we have numerically investigated, the disordered ground states are unique such that they can always be superposed onto each other or their mirror image. At low energies, the density of states obtained from simulations matches those calculated from the harmonic approximation near a single ground state, further confirming ground-state uniqueness. Our discovery provides singular examples in which entropy and disorder are at odds with one another. The zero-entropy ground states provide a unique perspective on the celebrated Kauzmann-entropy crisis in which the extrapolated entropy of a supercooled liquid drops below that of the crystal. We expect that our disordered unique patterns to be of value in fields beyond glass physics, including applications in cryptography as pseudorandom functions with tunable computational complexity.

Spin-state crossover and low-temperature magnetic state in yttrium-doped Pr0.7Ca0.3CoO3

NASA Astrophysics Data System (ADS)

Knížek, K.; Hejtmánek, J.; Maryško, M.; Novák, P.; Šantavá, E.; Jirák, Z.; Naito, T.; Fujishiro, H.; de la Cruz, Clarina

2013-12-01

The structural and magnetic properties of two mixed-valence cobaltites with a formal population of 0.30 Co4+ ions per f.u., (Pr1-yYy)0.7Ca0.3CoO3 (y=0 and 0.15), have been studied down to very low temperatures by means of high-resolution neutron diffraction, SQUID magnetometry, and heat-capacity measurements. The results are interpreted within the scenario of the spin-state crossover from a room-temperature mixture of the intermediate-spin Co3+ and low-spin Co4+ (IS/LS) to the LS/LS mixture in the sample ground states. In contrast to the yttrium-free y=0 that retains the metallic-like character and exhibits ferromagnetic (FM) ordering below 55 K, the doped system y=0.15 undergoes a first-order metal-insulator transition at 132 K, during which not only the crossover to low-spin states but also a partial electron transfer from Pr3+ 4f to cobalt 3d states takes place simultaneously. Taking into account the nonmagnetic character of LS Co3+, such a valence shift electronic transition causes a magnetic dilution, formally to 0.12 LS Co4+ or 0.12 t2g hole spins per f.u., which is the reason for an insulating, highly nonuniform magnetic ground state without long-range order. Nevertheless, even in that case there exists a relatively strong molecular field distributed over all the crystal lattice. It is argued that the spontaneous FM order in y=0 and the existence of strong FM correlations in y=0.15 apparently contradict the single t2g band character of LS/LS phase. The explanation we suggest relies on a model of the defect-induced, itinerant hole-mediated magnetism, where the defects are identified with the magnetic high-spin Co3+ species stabilized near oxygen vacancies.

Quantum chemical study of relative reactivities of a series of amines and nitriles - Relevance to prebiotic chemistry

NASA Technical Reports Server (NTRS)

Loew, G. H.; Berkowitz, D.; Chang, S.

1975-01-01

Using the Iterative Extended Huckel Theory (IEHT) calculations of the electron distribution and orbital energies of a series of thirteen amines, nitriles and amino-nitriles relevant to prebiotic and cosmo-chemistry have been carried out. Ground state properties such as the energy and nature of the highest occupied (HOMO) and lowest empty (LEMO) molecular orbitals, net atomic charges and number of nonbonding electrons have been identified as criteria for correlating the relative nucleophilicity of amine and nitrile nitrogens and the electrophilicity of nitrile and other unsaturated carbon atoms. The results of such correlations can be partially verified by known chemical behavior of these compounds and are used to predict and understand their role in prebiotic organic synthesis.

Public health, science, and policy debate: being right is not enough.

PubMed

Camargo, Kenneth; Grant, Roy

2015-02-01

Public health is usually enacted through public policies, necessitating that the public engage in debates that, ideally, are grounded in solid scientific findings. Mistrust in science, however, has compromised the possibility of deriving sound policy from such debates, partially owing to justified concerns regarding undue interference and even outright manipulation by commercial interests. This situation has generated problematic impasses, one of which is the emergence of an anti-vaccination movement that is already affecting public health, with a resurgence in the United States of preventable diseases thought to have been eradicated. Drawing on British sociologist Harry Collins' work on expertise, we propose a theoretical framework in which the paralyzing, undue public distrust of science can be analyzed and, it is hoped, overcome.

Magnetic properties of rare-earth sulfide YbAgS2

NASA Astrophysics Data System (ADS)

Iizuka, Ryosuke; Numakura, Ryosuke; Michimura, Shinji; Katano, Susumu; Kosaka, Masashi

2018-05-01

We have succeeded in synthesizing single-phase polycrystalline samples of YbAgS2 belonging to the tetragonal system with space group I41 md . YbAgS2 shows an antiferromagnetic transition at TN = 6.6 K . The effective magnetic moment is in good agreement with the theoretical value for Yb3+ free ion. A broad anomaly is observed just above TN in the temperature dependence of magnetic susceptibility. The entropy released at TN is only about half of Rln2 expected for a Kramers doublet ground state. We consider that these phenomena are due to the existence of short-range magnetic correlations rather than the partial screening of the Yb moments by conduction electrons via the Kondo effect.

Bi-layer graphene structure with non-equivalent planes: Magnetic properties study

NASA Astrophysics Data System (ADS)

Mhirech, A.; Aouini, S.; Alaoui-Ismaili, A.; Bahmad, L.

2018-05-01

In this paper, we study the magnetic properties of a ferromagnetic bi-layer graphene structure with non-equivalent planes. The geometry of the studied system is formed by two layers (A) and (B) consisting of the spins σ = 1 / 2 and S = 1 . For this purpose, the influence of the coupling exchange interactions, the external magnetic and the crystal fields are investigated and presented as well as the ground state phase diagrams. The Monte Carlo simulations have been used to examine the behavior of the partial and the total magnetizations as a function of the system parameters. These effects on the compensation and critical temperatures behavior are also presented in different phase diagrams, for the studied system.

Charging rates of metal-dielectric structures. [with implications for spacecraft

NASA Technical Reports Server (NTRS)

Purvis, C. K.; Staskus, J. V.; Roche, J. C.; Berkopec, F. D.

1979-01-01

Metal plates partially covered by 0.01-centimeter-thick fluorinated ethylene-propylene (FEP) Teflon were charged in the Lewis Research Center's geomagnetic substorm simulation facility using 5-, 8-, 10-, and 12-kilovolt electron beams. Surface voltage as a function of time was measured for various initial conditions (Teflon discharged or precharged) with the metal plate grounded or floating. Results indicate that both the charging rates and the levels to which the samples become charged are influenced by the geometry and initial charge state of the insulating surfaces. The experiments are described and the results are presented and discussed. NASA charging analyzer program (NASCAP) models of the experiments have been generated, and the predictions obtained are described. Implications of the study results for spacecraft are discussed.

Quasi-Particle Self-Consistent GW for Molecules.

PubMed

Kaplan, F; Harding, M E; Seiler, C; Weigend, F; Evers, F; van Setten, M J

2016-06-14

We present the formalism and implementation of quasi-particle self-consistent GW (qsGW) and eigenvalue only quasi-particle self-consistent GW (evGW) adapted to standard quantum chemistry packages. Our implementation is benchmarked against high-level quantum chemistry computations (coupled-cluster theory) and experimental results using a representative set of molecules. Furthermore, we compare the qsGW approach for five molecules relevant for organic photovoltaics to self-consistent GW results (scGW) and analyze the effects of the self-consistency on the ground state density by comparing calculated dipole moments to their experimental values. We show that qsGW makes a significant improvement over conventional G0W0 and that partially self-consistent flavors (in particular evGW) can be excellent alternatives.

Classification of matrix-product ground states corresponding to one-dimensional chains of two-state sites of nearest neighbor interactions

NASA Astrophysics Data System (ADS)

Fatollahi, Amir H.; Khorrami, Mohammad; Shariati, Ahmad; Aghamohammadi, Amir

2011-04-01

A complete classification is given for one-dimensional chains with nearest-neighbor interactions having two states in each site, for which a matrix product ground state exists. The Hamiltonians and their corresponding matrix product ground states are explicitly obtained.

Exponentially-Biased Ground-State Sampling of Quantum Annealing Machines with Transverse-Field Driving Hamiltonians

NASA Technical Reports Server (NTRS)

Mandra, Salvatore

2017-01-01

We study the performance of the D-Wave 2X quantum annealing machine on systems with well-controlled ground-state degeneracy. While obtaining the ground state of a spin-glass benchmark instance represents a difficult task, the gold standard for any optimization algorithm or machine is to sample all solutions that minimize the Hamiltonian with more or less equal probability. Our results show that while naive transverse-field quantum annealing on the D-Wave 2X device can find the ground-state energy of the problems, it is not well suited in identifying all degenerate ground-state configurations associated to a particular instance. Even worse, some states are exponentially suppressed, in agreement with previous studies on toy model problems [New J. Phys. 11, 073021 (2009)]. These results suggest that more complex driving Hamiltonians are needed in future quantum annealing machines to ensure a fair sampling of the ground-state manifold.

Over ground walking and body weight supported walking improve mobility equally in cerebral palsy: a randomised controlled trial.

PubMed

Swe, Ni Ni; Sendhilnnathan, Sunitha; van Den Berg, Maayken; Barr, Christopher

2015-11-01

To assess partial body weight supported treadmill training versus over ground training for walking ability in children with mild to moderate cerebral palsy. Randomised controlled trial. A Special Needs school in Singapore. Thirty children with cerebral palsy, aged 6-18, with a Gross Motor Function Classification System score of II-III. Two times 30 minute sessions of walking training per week for 8 weeks, progressed as tolerated, either over ground (control) or using partial body weight supported treadmill training (intervention). The 10 metre walk test, and the 6 minute walk test. Secondary measures were sub-sections D and E on the Gross Motor Function Measure. Outcomes were assessed at baseline, and after 4 and 8 weeks of training. There was no effect of group allocation on any outcome measure, while time was a significant factor for all outcomes. Walking speed improved significantly more in the intervention group by week 4 (0.109 (0.067)m/s vs 0.048 (0.071)m/s, P=0.024) however by week 8 the change from baseline was similar (intervention 0.0160 (0.069)m/s vs control 0.173 (0.109)m/s, P=0.697). All gains made by week 4 were significantly improved on by week 8 for the 10 metre walk test, 6 minute walk test, and the gross motor function measure. Partial body weight supported treadmill training is no more effective than over ground walking at improving aspects of walking and function in children with mild to moderate cerebral palsy. Gains seen in 4 weeks can be furthered by 8 weeks. © The Author(s) 2015.

Partial dissolution of ACQ-treated wood in lithium chloride/N-methyl-2-pyrrolidinone: Separation of copper from potential lignocellulosic feedstocks

Treesearch

Thomas L. Eberhardt; Stan Lebow; Karen G. Reed

2012-01-01

A cellulose solvent system based on lithium chloride (LiCl) in N-methyl-2-pyrrolidinone (NMP) was used to assess the merits of partial dissolutions of coarsely ground wood samples. Alkaline Copper Quaternary (ACQ)-treated pine wood was of particular interest for treatment given the potential to generate a copper- rich stream apart from solid and/or liquid...

Multinational Experiment 7. Outcome 3 - Cyber Domain, Objective 3.2: Information Sharing Framework

DTIC Science & Technology

2013-01-22

Assessments internally and across the community of interest, using an agreed methodology, such as ISO /IEC 27000 series. This should cover: (1) Policies...so that identities can be revealed if there are grounds to do so. (See ISO /IEC 29191 – Partially anonymous, partially unlinkable authentication...available from national ISO bodies). Generation and Maintenance of Cyber Situational Awareness 69. Cyber SA depends on all participating organisations

Orbital stability and energy estimate of ground states of saturable nonlinear Schrödinger equations with intensity functions in R2

NASA Astrophysics Data System (ADS)

Lin, Tai-Chia; Wang, Xiaoming; Wang, Zhi-Qiang

2017-10-01

Conventionally, the existence and orbital stability of ground states of nonlinear Schrödinger (NLS) equations with power-law nonlinearity (subcritical case) can be proved by an argument using strict subadditivity of the ground state energy and the concentration compactness method of Cazenave and Lions [4]. However, for saturable nonlinearity, such an argument is not applicable because strict subadditivity of the ground state energy fails in this case. Here we use a convexity argument to prove the existence and orbital stability of ground states of NLS equations with saturable nonlinearity and intensity functions in R2. Besides, we derive the energy estimate of ground states of saturable NLS equations with intensity functions using the eigenvalue estimate of saturable NLS equations without intensity function.

Thermodynamic stability of boron: the role of defects and zero point motion.

PubMed

van Setten, Michiel J; Uijttewaal, Matthé A; de Wijs, Gilles A; de Groot, Robert A

2007-03-07

Its low weight, high melting point, and large degree of hardness make elemental boron a technologically interesting material. The large number of allotropes, mostly containing over a hundred atoms in the unit cell, and their difficult characterization challenge both experimentalists and theoreticians. Even the ground state of this element is still under discussion. For over 30 years, scientists have attempted to determine the relative stability of alpha- and beta-rhombohedral boron. We use density functional calculations in the generalized gradient approximation to study a broad range of possible beta-rhombohedral structures containing interstitial atoms and partially occupied sites within a 105 atoms framework. The two most stable structures are practically degenerate in energy and semiconducting. One contains the experimental 320 atoms in the hexagonal unit cell, and the other contains 106 atoms in the triclinic unit cell. When populated with the experimental 320 electrons, the 106 atom structure exhibits a band gap of 1.4 eV and an in-gap hole trap at 0.35 eV above the valence band, consistent with known experiments. The total energy of these two structures is 23 meV/B lower than the original 105 atom framework, but it is still 1 meV/B above the alpha phase. Adding zero point energies finally makes the beta phase the ground state of elemental boron by 3 meV/B. At finite temperatures, the difference becomes even larger.

Reconnaissance investigation of ground-water supply for Dora Belle Campground, Shaver Lake, California

USGS Publications Warehouse

Davis, G.H.

1957-01-01

At the request of the United States Forest Service, the Ground Water Branch of the United Stated Geological Survey made a reconnaissance of the geologic features and water resources of the Dora Belle Campground in Sierra National Forest on the shore of Shaver Lake, Fresno County, California. Basically, the water-supply problem at Dora Belle Campground is that the present supply obtained from a spring is not adequate to meet the present summer demand, and is of poor quality. Plans call for a considerable increase in camping facilities.. This, it is imperative that the present supply be augmented or, preferably, be replaced entirely. the Forest Service estimated the future peak demand to be about 25,00 gallons per day. On October 28, 1957, the writer examined the are in the company of C. H. Fankboner, Assistant Forest Engineer, Sierra National Forest, and Ben Dix, Construction and Maintenance Foreman, Pine Ridge District. Field work, done on October 28th and 29th, consisted of a brief geologic reconnaissance to determine the rock types and geologic structure, and a hydrologic reconnaissance consisting of a partial inventory of water walls and springs in the vicinity of the campground. A spring box near the western edge of Bell Diamond Meadow was pumped out with a Forest Service pump truck to determine its rate of recovery and potential production.

Symmetry-breaking dynamics of the finite-size Lipkin-Meshkov-Glick model near ground state

NASA Astrophysics Data System (ADS)

Huang, Yi; Li, Tongcang; Yin, Zhang-qi

2018-01-01

We study the dynamics of the Lipkin-Meshkov-Glick (LMG) model with a finite number of spins. In the thermodynamic limit, the ground state of the LMG model with an isotropic Hamiltonian in the broken phase breaks to a mean-field ground state with a certain direction. However, when the spin number N is finite, the exact ground state is always unique and is not given by a classical mean-field ground state. Here, we prove that when N is large but finite, through a tiny external perturbation, a localized state which is close to a mean-field ground state can be prepared, which mimics spontaneous symmetry breaking. Also, we find the localized in-plane spin polarization oscillates with two different frequencies ˜O (1 /N ) , and the lifetime of the localized state is long enough to exhibit this oscillation. We numerically test the analytical results and find that they agree very well with each other. Finally, we link the phenomena to quantum time crystals and time quasicrystals.

Optical Feshbach resonances and ground-state-molecule production in the RbHg system

NASA Astrophysics Data System (ADS)

Borkowski, Mateusz; Muñoz Rodriguez, Rodolfo; Kosicki, Maciej B.; Ciuryło, Roman; Żuchowski, Piotr S.

2017-12-01

We present the prospects for photoassociation, optical control of interspecies scattering lengths, and, finally, the production of ultracold absolute ground-state molecules in the Rb+Hg system. We use the state-of-the-art ab initio methods for the calculations of ground- [CCSD(T)] and excited-state (EOM-CCSD) potential curves. The RbHg system, thanks to the wide range of stable Hg bosonic isotopes, offers possibilities for mass tuning of ground-state interactions. The optical lengths describing the strengths of optical Feshbach resonances near the Rb transitions are favorable even at large laser detunings. Ground-state RbHg molecules can be produced with efficiencies ranging from about 20% for deeply bound to at least 50% for weakly bound states close to the dissociation limit. Finally, electronic transitions with favorable Franck-Condon factors can be found for the purposes of a STIRAP transfer of the weakly bound RbHg molecules to the absolute ground state using commercially available lasers.

Area estimation using multiyear designs and partial crop identification

NASA Technical Reports Server (NTRS)

Sielken, R. L., Jr.

1984-01-01

Statistical procedures were developed for large area assessments using both satellite and conventional data. Crop acreages, other ground cover indices, and measures of change were the principal characteristics of interest. These characteristics are capable of being estimated from samples collected possibly from several sources at varying times, with different levels of identification. Multiyear analysis techniques were extended to include partially identified samples; the best current year sampling design corresponding to a given sampling history was determined; weights reflecting the precision or confidence in each observation were identified and utilized, and the variation in estimates incorporating partially identified samples were quantified.

Improved numerical methods for infinite spin chains with long-range interactions

NASA Astrophysics Data System (ADS)

Nebendahl, V.; Dür, W.

2013-02-01

We present several improvements of the infinite matrix product state (iMPS) algorithm for finding ground states of one-dimensional quantum systems with long-range interactions. As a main ingredient, we introduce the superposed multioptimization method, which allows an efficient optimization of exponentially many MPS of different lengths at different sites all in one step. Here, the algorithm becomes protected against position-dependent effects as caused by spontaneously broken translational invariance. So far, these have been a major obstacle to convergence for the iMPS algorithm if no prior knowledge of the system's translational symmetry was accessible. Further, we investigate some more general methods to speed up calculations and improve convergence, which might be partially interesting in a much broader context, too. As a more special problem, we also look into translational invariant states close to an invariance-breaking phase transition and show how to avoid convergence into wrong local minima for such systems. Finally, we apply these methods to polar bosons with long-range interactions. We calculate several detailed Devil's staircases with the corresponding phase diagrams and investigate some supersolid properties.

Magnetic properties of Mn-doped GaN with defects: ab-initio calculations

NASA Astrophysics Data System (ADS)

Salmani, E.; Benyoussef, A.; Ez-Zahraouy, H.; H. Saidi, E.

2011-08-01

According to first-principles density functional calculations, we have investigated the magnetic properties of Mn-doped GaN with defects, Ga1-x-yVGxMny N1-z-tVNzOt with Mn substituted at Ga sites, nitrogen vacancies VN, gallium vacancies VG and oxygen substituted at nitrogen sites. The magnetic interaction in Mn-doped GaN favours the ferromagnetic coupling via the double exchange mechanism. The ground state is found to be well described by a model based on a Mn3+-d5 in a high spin state coupled via a double exchange to a partially delocalized hole accommodated in the 2p states of neighbouring nitrogen ions. The effect of defects on ferromagnetic coupling is investigated. It is found that in the presence of donor defects, such as oxygen substituted at nitrogen sites, nitrogen vacancy antiferromagnetic interactions appear, while in the case of Ga vacancies, the interactions remain ferromagnetic; in the case of acceptor defects like Mg and Zn codoping, ferromagnetism is stabilized. The formation energies of these defects are computed. Furthermore, the half-metallic behaviours appear in some studied compounds.

Electron-Impact Excitation of Ions Effects of Presence of Another Ion

NASA Astrophysics Data System (ADS)

Ohsaki, Akihiko; Nagasaki, Satoshi; Uramoto, Sei-iti; Takayanagi, Kazuo

2000-02-01

Present work gives for the first time the formulation of the two-center Coulomb-Born approximation (TCCBA) and presents some calculations for the electron-impact excitations in electron-ion-ion systems.The effect of the third body was relatively small in the cases studied so far. However, if the third body is a bare ion with a charge larger than the target ion, there will be a marked influence of the three-body collisions.Utilizing TCCBA we present the total and partial cross sections of hydrogen-like ions He+(Z=2), and C5+(Z=6) in the hydrogen plasma from the ground states 1s to the excited states 2s and 2p0, 2p± for the collision energies from 0.4Z2 to 2Z2 a.u.; for the excited states of the target ions, Stark effect is also studied.It is found that the presence of another ion have little effect on the 1s-2s transition and the 2s-2p Stark mixing has a prominent effect.

Color screening and regeneration of bottomonia in high-energy heavy-ion collisions

NASA Astrophysics Data System (ADS)

Du, X.; He, M.; Rapp, R.

2017-11-01

The production of ground-state and excited bottomonia in ultrarelativistic heavy-ion collisions is investigated within a kinetic-rate equation approach including regeneration. We augment our previous calculations by an improved treatment of medium effects, with temperature-dependent binding energies and pertinent reaction rates, B -meson resonance states in the equilibrium limit near the hadronization temperature, and a lattice-QCD based equation of state for the bulk medium. In addition to the centrality dependence of the bottomonium yields, we compute their transverse-momentum (pT) spectra and elliptic flow with momentum-dependent reaction rates and a regeneration component based on b -quark spectra from a nonperturbative transport model of heavy-quark diffusion. The latter has noticeable consequences for the shape of the bottomonium pT spectra. We quantify how uncertainties in the various modeling components affect the predictions for observables. Based on this we argue that the Υ (1 S ) suppression is a promising observable for mapping out the in-medium properties of the QCD force, while Υ (2 S ) production can help to quantify the role of regeneration from partially thermalized b quarks.

Ultrafast Electronic Relaxation through a Conical Intersection: Nonadiabatic Dynamics Disentangled through an Oscillator Strength-Based Diabatization Framework

DOE PAGES

Medders, Gregory R.; Alguire, Ethan C.; Jain, Amber; ...

2017-01-18

Here, we employ surface hopping trajectories to model the short-time dynamics of gas-phase and partially solvated 4-(N,N-dimethylamino)benzonitrile (DMABN), a dual fluorescent molecule that is known to undergo a nonadiabatic transition through a conical intersection. To compare theory vs time-resolved fluorescence measurements, we calculate the mixed quantum–classical density matrix and the ensemble averaged transition dipole moment. We introduce a diabatization scheme based on the oscillator strength to convert the TDDFT adiabatic states into diabatic states of L a and L b character. Somewhat surprisingly, we find that the rate of relaxation reported by emission to the ground state is almost 50%more » slower than the adiabatic population relaxation. Although our calculated adiabatic rates are largely consistent with previous theoretical calculations and no obvious effects of decoherence are seen, the diabatization procedure introduced here enables an explicit picture of dynamics in the branching plane, raising tantalizing questions about geometric phase effects in systems with dozens of atoms.« less

Multiphoton manipulations of enzymatic photoactivity in aspartate aminotransferase.

PubMed

Hill, Melissa P; Freer, Lucy H; Vang, Mai C; Carroll, Elizabeth C; Larsen, Delmar S

2011-04-21

The aspartate aminotransferase (AAT) enzyme utilizes the chromophoric pyridoxal 5'-phosphate (PLP) cofactor to facilitate the transamination of amino acids. Recently, we demonstrated that, upon exposure to blue light, PLP forms a reactive triplet state that rapidly (in microseconds) generates the high-energy quinonoid intermediate when bound to PLP-dependent enzymes [J. Am. Chem. Soc.2010, 132 (47), 16953-16961]. This increases the net catalytic activity (k(cat)) of AAT, since formation of the quinonoid is partially rate limiting via the thermally activated enzymatic pathway. The magnitude of observed photoenhancement initially scales linearly with pump fluence; however when a critical threshold is exceeded, the photoactivity saturates and is even suppressed at greater excitation fluences. The photodynamic mechanisms associated with this suppression behavior are characterized with the use of ultrafast multipulse pump-dump-probe and pump-repump-probe transient absorption techniques in combination with complementary two-color, steady-state excitation assays. Via multistate kinetic modeling of the transient ultrafast data and the steady-state assay data, the nonmonotonic incident power dependence of the photoactivty in AAT is decomposed into contributions from high-intensity dumping of the excited singlet state and repumping of the excited triplet state with induces the repopulation of the ground state via rapid intersystem crossing in the higher-lying triplet electronic manifold.

Photogenic partial seizures.

PubMed

Hennessy, M J; Binnie, C D

2000-01-01

To establish the incidence and symptoms of partial seizures in a cohort of patients investigated on account of known sensitivity to intermittent photic stimulation and/or precipitation of seizures by environmental visual stimuli such as television (TV) screens or computer monitors. We report 43 consecutive patients with epilepsy, who had exhibited a significant EEG photoparoxysmal response or who had seizures precipitated by environmental visual stimuli and underwent detailed assessment of their photosensitivity in the EEG laboratory, during which all were questioned concerning their ictal symptoms. All patients were considered on clinical grounds to have an idiopathic epilepsy syndrome. Twenty-eight (65%) patients reported visually precipitated attacks occurring initially with maintained consciousness, in some instances evolving to a period of confusion or to a secondarily generalized seizure. Visual symptoms were most commonly reported and included positive symptoms such as coloured circles or spots, but also blindness and subjective symptoms such as "eyes going funny." Other symptoms described included nonspecific cephalic sensations, deja-vu, auditory hallucinations, nausea, and vomiting. No patient reported any clear spontaneous partial seizures, and there were no grounds for supposing that any had partial epilepsy excepting the ictal phenomenology of some or all of the visually induced attacks. These findings provide clinical support for the physiological studies that indicate that the trigger mechanism for human photosensitivity involves binocularly innervated cells located in the visual cortex. Thus the visual cortex is the seat of the primary epileptogenic process, and the photically triggered discharges and seizures may be regarded as partial with secondary generalization.

The molecular and electronic structure of s-tetrazine in the ground and first excited state: A theoretical investigation

NASA Astrophysics Data System (ADS)

Schütz, Martin; Hutter, Jürg; Lüthi, Hans Peter

1995-10-01

The ground- and first excited state of s-tetrazine arising from a π*←n excitation (1Ag,1B3u) have been studied using the complete active space (CASSCF) and the second order multiconfiguration perturbation theory (CASPT2) ab initio methods. The focus of this study is on the effect of the electronic excitation on the molecular structure and on those electronic properties which are important to model the solvatochromatic behavior of the molecule in polymer matrices as used in permanent hole burning experiments. Since the accurate computation of excited state molecular properties represents a major challenge for today's numerical quantum chemistry, some technical aspects are also considered. The present study shows that the change in geometry upon electronic excitation is small. This is in partial contradiction with the experimental studies which however disagree among themselves [see K. K. Innes, I. G. Ross, and W. R. Moomaw, J. Mol. Spectrosc. 132, 492 (1988), and R. E. Smalley, L. Wharton, and D. H. Levi, ibid. 66, 375 (1977)]. This study also confirms that the first excited state equilibrium structure is of D2h symmetry. In an earlier theoretical study it was found that the D2h symmetry structure may represent a saddle point rather than a minimum on the excited state potential surface [see A. C. Scheiner and H. F. Schaefer III, J. Chem. Phys. 87, 3539 (1987)]. In the first excited state, we observe an increase of the mean polarizability of s-tetrazine along with an enhanced anisotropy. The change in the polarizability is almost exclusively in the ``in-plane'' components of the tensor; the polarizability in the vertical direction is nearly unchanged. This observation questions recent experimental results reported for this molecule [see S. Heitz, D. Weidnauer, and A. Hese, J. Chem. Phys. 95, 7952 (1991)].

Ultraviolet photodissociation dynamics of the n-propyl and i-propyl radicals

DOE Office of Scientific and Technical Information (OSTI.GOV)

Song, Yu; Zheng, Xianfeng; Zhou, Weidong

2015-06-14

Ultraviolet (UV) photodissociation dynamics of jet-cooled n-propyl (n-C{sub 3}H{sub 7}) radical via the 3s Rydberg state and i-propyl (i-C{sub 3}H{sub 7}) radical via the 3p Rydberg states are studied in the photolysis wavelength region of 230–260 nm using high-n Rydberg atom time-of-flight and resonance enhanced multiphoton ionization techniques. The H-atom photofragment yield spectra of the n-propyl and i-propyl radicals are broad and in good agreement with the UV absorption spectra. The H + propene product translational energy distributions, P(E{sub T})’s, of both n-propyl and i-propyl are bimodal, with a slow component peaking around 5-6 kcal/mol and a fast one peakingmore » at ∼50 kcal/mol (n-propyl) and ∼45 kcal/mol (i-propyl). The fraction of the average translational energy in the total excess energy, 〈f{sub T}〉, is 0.3 for n-propyl and 0.2 for i-propyl, respectively. The H-atom product angular distributions of the slow components of n-propyl and i-propyl are isotropic, while that of the fast component of n-propyl is anisotropic (with an anisotropy parameter ∼0.8) and that of i-propyl is nearly isotropic. Site-selective loss of the β hydrogen atom is confirmed using the partially deuterated CH{sub 3}CH{sub 2}CD{sub 2} and CH{sub 3}CDCH{sub 3} radicals. The bimodal translational energy and angular distributions indicate two dissociation pathways to the H + propene products in the n-propyl and i-propyl radicals: (i) a unimolecular dissociation pathway from the hot ground-state propyl after internal conversion from the 3s and 3p Rydberg states and (ii) a direct, prompt dissociation pathway coupling the Rydberg excited states to a repulsive part of the ground-state surface, presumably via a conical intersection.« less

Ground-state energies of the nonlinear sigma model and the Heisenberg spin chains

NASA Technical Reports Server (NTRS)

Zhang, Shoucheng; Schulz, H. J.; Ziman, Timothy

1989-01-01

A theorem on the O(3) nonlinear sigma model with the topological theta term is proved, which states that the ground-state energy at theta = pi is always higher than the ground-state energy at theta = 0, for the same value of the coupling constant g. Provided that the nonlinear sigma model gives the correct description for the Heisenberg spin chains in the large-s limit, this theorem makes a definite prediction relating the ground-state energies of the half-integer and the integer spin chains. The ground-state energies obtained from the exact Bethe ansatz solution for the spin-1/2 chain and the numerical diagonalization on the spin-1, spin-3/2, and spin-2 chains support this prediction.

Isoflavone Retention during Processing, Bioaccessibility, and Transport by Caco-2 Cells: Effects of Source and Amount of Fat in a Soy Soft Pretzel

PubMed Central

Simmons, Amber L.; Chitchumroonchokchai, Chureeporn; Vodovotz, Yael; Failla, Mark L.

2014-01-01

The impact of source and amount of lipid used to prepare a soy soft pretzel on the bioaccessibility and transport of isoflavones was investigated using the coupled in vitro digestion/Caco-2 human cell model. Pretzels were prepared without or with 2.9 or 6.0% exogenous lipid from either shortening, canola oil, ground almond, or ground hazelnut. The isoflavone backbone structure was stable during pretzel production, although there was partial conversion from malonyl and acetyl glucosides to simple glucosides and aglycones. Endogenous β-glucosidase activity in ground almond facilitated partial conversion of simple glucosides to aglycones during proofing, resulting in a slight decrease in bioaccessibility of isoflavones as compared with other sources of lipid. Amount and source of lipid did not affect bioaccessibility or uptake and metabolism of isoflavones by Caco-2 cells, although transport across the monolayer was greater with the lesser amount of shortening. These results suggest that the isoflavone structure, but not source or amount of lipid in a soy pretzel, may affect bioavailability of isoflavones. PMID:23167916

Matrix-product-operator approach to the nonequilibrium steady state of driven-dissipative quantum arrays

NASA Astrophysics Data System (ADS)

Mascarenhas, Eduardo; Flayac, Hugo; Savona, Vincenzo

2015-08-01

We develop a numerical procedure to efficiently model the nonequilibrium steady state of one-dimensional arrays of open quantum systems based on a matrix-product operator ansatz for the density matrix. The procedure searches for the null eigenvalue of the Liouvillian superoperator by sweeping along the system while carrying out a partial diagonalization of the single-site stationary problem. It bears full analogy to the density-matrix renormalization-group approach to the ground state of isolated systems, and its numerical complexity scales as a power law with the bond dimension. The method brings considerable advantage when compared to the integration of the time-dependent problem via Trotter decomposition, as it can address arbitrarily long-ranged couplings. Additionally, it ensures numerical stability in the case of weakly dissipative systems thanks to a slow tuning of the dissipation rates along the sweeps. We have tested the method on a driven-dissipative spin chain, under various assumptions for the Hamiltonian, drive, and dissipation parameters, and compared the results to those obtained both by Trotter dynamics and Monte Carlo wave function methods. Accurate and numerically stable convergence was always achieved when applying the method to systems with a gapped Liouvillian and a nondegenerate steady state.

40 CFR 141.401 - Sanitary surveys for ground water systems.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 23 2011-07-01 2011-07-01 false Sanitary surveys for ground water...) WATER PROGRAMS (CONTINUED) NATIONAL PRIMARY DRINKING WATER REGULATIONS Ground Water Rule § 141.401 Sanitary surveys for ground water systems. (a) Ground water systems must provide the State, at the State's...

Classification of multipartite entanglement via negativity fonts

NASA Astrophysics Data System (ADS)

Sharma, S. Shelly; Sharma, N. K.

2012-04-01

Partial transposition of state operator is a well-known tool to detect quantum correlations between two parts of a composite system. In this paper, the global partial transpose (GPT) is linked to conceptually multipartite underlying structures in a state—the negativity fonts. If K-way negativity fonts with nonzero determinants exist, then selective partial transposition of a pure state, involving K of the N qubits (K⩽N), yields an operator with negative eigenvalues, identifying K-body correlations in the state. Expansion of GPT in terms of K-way partially transposed (KPT) operators reveals the nature of intricate intrinsic correlations in the state. Classification criteria for multipartite entangled states based on the underlying structure of global partial transpose of canonical state are proposed. The number of N-partite entanglement types for an N-qubit system is found to be 2N-1-N+2, while the number of major entanglement classes is 2N-1-1. Major classes for three- and four-qubit states are listed. Subclasses are determined by the number and type of negativity fonts in canonical states.

Ground-state and Thermodynamic Properties of an S = 1 Kitaev Model

NASA Astrophysics Data System (ADS)

Koga, Akihisa; Tomishige, Hiroyuki; Nasu, Joji

2018-06-01

We study the ground-state and thermodynamic properties of an S = 1 Kitaev model. We first clarify the existence of global parity symmetry in addition to the local symmetry on each plaquette, which enables us to perform large-scale calculations on up to 24 sites. It is found that the ground state should be singlet, and its energy is estimated as E/N ˜ -0.65J, where J is the Kitaev exchange coupling. We find that the lowest excited state belongs to the same subspace as the ground state, and that the gap decreases monotonically with increasing system size, which suggests that the ground state of the S = 1 Kitaev model is gapless. Using the thermal pure quantum states, we clarify the finite temperature properties characteristic of the Kitaev models with S ≤ 2.

On the ground state of Yang-Mills theory

NASA Astrophysics Data System (ADS)

Bakry, Ahmed S.; Leinweber, Derek B.; Williams, Anthony G.

2011-08-01

We investigate the overlap of the ground state meson potential with sets of mesonic-trial wave functions corresponding to different gluonic distributions. We probe the transverse structure of the flux tube through the creation of non-uniform smearing profiles for the string of glue connecting two color sources in Wilson loop operator. The non-uniformly UV-regulated flux-tube operators are found to optimize the overlap with the ground state and display interesting features in the ground state overlap.

Ice-Shelf Tidal Flexure and Subglacial Pressure Variations

NASA Technical Reports Server (NTRS)

Walker, Ryan T.; Parizek, Byron R.; Alley, Richard B.; Anandakrishnan, Sridhar; Riverman, Kiya L.; Christianson, Knut

2013-01-01

We develop a model of an ice shelf-ice stream system as a viscoelastic beam partially supported by an elastic foundation. When bed rock near the grounding line acts as a fulcrum, leverage from the ice shelf dropping at low tide can cause significant (approx 1 cm) uplift in the first few kilometers of grounded ice.This uplift and the corresponding depression at high tide lead to basal pressure variations of sufficient magnitude to influence subglacial hydrology.Tidal flexure may thus affect basal lubrication, sediment flow, and till strength, all of which are significant factors in ice-stream dynamics and grounding-line stability. Under certain circumstances, our results suggest the possibility of seawater being drawn into the subglacial water system. The presence of sea water beneath grounded ice would significantly change the radar reflectivity of the grounding zone and complicate the interpretation of grounded versus floating ice based on ice-penetrating radar observations.

Simulation of ground-water flow and land subsidence in the Antelope Valley ground-water basin, California

USGS Publications Warehouse

Leighton, David A.; Phillips, Steven P.

2003-01-01

Antelope Valley, California, is a topographically closed basin in the western part of the Mojave Desert, about 50 miles northeast of Los Angeles. The Antelope Valley ground-water basin is about 940 square miles and is separated from the northern part of Antelope Valley by faults and low-lying hills. Prior to 1972, ground water provided more than 90 percent of the total water supply in the valley; since 1972, it has provided between 50 and 90 percent. Most ground-water pumping in the valley occurs in the Antelope Valley ground-water basin, which includes the rapidly growing cities of Lancaster and Palmdale. Ground-water-level declines of more than 200 feet in some parts of the ground-water basin have resulted in an increase in pumping lifts, reduced well efficiency, and land subsidence of more than 6 feet in some areas. Future urban growth and limits on the supply of imported water may continue to increase reliance on ground water. To better understand the ground-water flow system and to develop a tool to aid in effectively managing the water resources, a numerical model of ground-water flow and land subsidence in the Antelope Valley ground-water basin was developed using old and new geohydrologic information. The ground-water flow system consists of three aquifers: the upper, middle, and lower aquifers. The aquifers, which were identified on the basis of the hydrologic properties, age, and depth of the unconsolidated deposits, consist of gravel, sand, silt, and clay alluvial deposits and clay and silty clay lacustrine deposits. Prior to ground-water development in the valley, recharge was primarily the infiltration of runoff from the surrounding mountains. Ground water flowed from the recharge areas to discharge areas around the playas where it discharged either from the aquifer system as evapotranspiration or from springs. Partial barriers to horizontal ground-water flow, such as faults, have been identified in the ground-water basin. Water-level declines owing to ground-water development have eliminated the natural sources of discharge, and pumping for agricultural and urban uses have become the primary source of discharge from the ground-water system. Infiltration of return flows from agricultural irrigation has become an important source of recharge to the aquifer system. The ground-water flow model of the basin was discretized horizontally into a grid of 43 rows and 60 columns of square cells 1 mile on a side, and vertically into three layers representing the upper, middle, and lower aquifers. Faults that were thought to act as horizontal-flow barriers were simulated in the model. The model was calibrated to simulate steady-state conditions, represented by 1915 water levels and transient-state conditions during 1915-95 using water-level and subsidence data. Initial estimates of the aquifer-system properties and stresses were obtained from a previously published numerical model of the Antelope Valley ground-water basin; estimates also were obtained from recently collected hydrologic data and from results of simulations of ground-water flow and land subsidence models of the Edwards Air Force Base area. Some of these initial estimates were modified during model calibration. Ground-water pumpage for agriculture was estimated on the basis of irrigated crop acreage and crop consumptive-use data. Pumpage for public supply, which is metered, was compiled and entered into a database used for this study. Estimated annual pumpage peaked at 395,000 acre-feet (acre-ft) in 1952 and then declined because of declining agricultural production. Recharge from irrigation-return flows was estimated to be 30 percent of agricultural pumpage; the irrigation-return flows were simulated as recharge to the regional water table 10 years following application at land surface. The annual quantity of natural recharge initially was based on estimates from previous studies. During model calibration, natural recharge was reduced from the initial

High-resolution threshold photoionization of N sub 2 O

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wiedmann, R.T.; Grant, E.R.; Tonkyn, R.G.

1991-07-15

Pulsed field ionization (PFI) has been used in conjunction with a coherent vuv source to obtain high-resolution threshold photoelectron spectra for the (000), (010), (020), and (100) vibrational states of the N{sub 2}O{sup +} cation. Simulations for the rotational profiles of each vibronic level were obtained by fitting the Buckingham--Orr--Sichel equations (A. D. Buckingham, B. J. Orr, and J. M. Sichel, Philos. Trans. R. Soc. London, Ser. A {bold 268}, 147 (1970)) using accurate spectroscopic constants for the ground states of the neutral and the ion. The relative branch intensities are interpreted in terms of the partial waves of themore » outgoing photoelectron to which the ionic core is coupled and in terms of the angular momentum transferred to the core. The PFI technique also allows us to report an improved value for the ionization potential of N{sub 2}O of 103 963{plus minus}5 cm{sup {minus}1}.« less

Water resources data for California, water year 1975; Volume 1: Colorado River basin, southern Great Basin from Mexican border to Mono Lake basin, and Pacific Slope basins from Tijuana River to Santa Maria River

USGS Publications Warehouse

,

1977-01-01

Water-resources data for the 1975 water year for California consist of records of streamflow and contents of reservoirs at gaging stations, partial-record stations, and miscellaneous sites; records of water quality including the physical, chemical, and biological characteristics of surface and ground water; and records of water levels in selected observation wells. Records for a few pertinent streamflow and water-quality stations in bordering States are also included. The records were collected and computed by the Water Resources Division of the U.S. Geological Survey under the direction of Lee R. Peterson, district chief; Winchell Smith, assistant district chief for hydrologic data; and Leonard N. Jorgensen, chief of the basic data section. These data represent that part of the National Water Data System collected by the Geological Survey and cooperating local, State, and Federal agencies in California.

The effects of linear assembly of two carbazole groups on acid-base and DNA-binding properties of a ruthenium(II) complex.

PubMed

Chen, Xi; Xue, Long-Xin; Ju, Chun-Chuan; Wang, Ke-Zhi

2013-07-01

A novel Ru(II) complex of [Ru(bpy)2(Hbcpip)](ClO4)2 {where bpy=2,2-bipyridine, Hbcpip=2-(4-(9H-3,9'-bicarbazol-9-yl)phenyl)-1H-imidazo[4,5-f][1,10]phenanthroline} is synthesized and characterized. Calf-thymus DNA-binding properties of the complex were studied by UV-vis absorption and luminescence titrations, steady-state emission quenching by [Fe(CN)6](4-), DNA competitive binding with ethidium bromide, thermal denaturation and DNA viscosity measurements. The results indicate that the complex partially intercalated into the DNA with a binding constant of (5.5±1.4)×10(5) M(-1) in buffered 50 mM NaCl. The acid-base properties of the complex were also studied by UV-visible and luminescence spectrophotometric pH titrations, and ground- and excited-state acidity ionization constant values were derived. Copyright © 2013 Elsevier B.V. All rights reserved.

Indocyanine green laser angiography improves deep inferior epigastric perforator flap outcomes following abdominal suction lipectomy.

PubMed

Casey, William J; Connolly, Katharine A; Nanda, Alisha; Rebecca, Alanna M; Perdikis, Galen; Smith, Anthony A

2015-03-01

The reliability of deep inferior epigastric artery perforator (DIEP) flap reconstruction following abdominal liposuction is controversial. The authors' early cases were technically successful; however, they experienced high partial flap loss and fat necrosis rates. The authors sought to compare DIEP flap outcomes in the setting of prior liposuction after the use of intraoperative indocyanine green angiography compared to when flaps were assessed on clinical grounds alone. A retrospective review of a consecutive series of DIEP flaps following liposuction at a single institution was performed, comparing those evaluated on clinical grounds alone and those in which indocyanine green angiography was used intraoperatively. Outcomes measured included anastomotic complications, total flap loss, partial flap loss, fat necrosis, and postoperative abdominal wounds. Thirteen DIEP flaps following prior liposuction were performed on 11 patients from July of 2003 through January of 2014. All patients had preoperative imaging with duplex ultrasound or computed tomographic angiography to analyze perforator suitability before surgical exploration. Seven flaps were evaluated intraoperatively on clinical grounds alone. Six flaps were assessed and modified based on indocyanine green angiography. All flaps were successful; however, partial flap loss and fat necrosis rates dropped from 71.4 percent to 0 percent when indocyanine green angiography was used intraoperatively (p = 0.02). Indocyanine green angiography is an excellent vascular imaging modality for intraoperative use to assess flap perfusion, and improves outcomes in DIEP flaps when harvested after prior abdominal suction lipectomy.

Welding fixture for joining bar-wound stator conductors

DOE Office of Scientific and Technical Information (OSTI.GOV)

De Souza, Urban J.; Rhoads, Frederick W.; Hanson, Justin

A fixture assembly for welding a plurality of stator wire end pairs may include an anvil, a movable clamp configured to translate between an unclamped state and a clamped state, a first grounding electrode, and a second grounding electrode. The movable clamp may be configured to urge the plurality of stator wire ends against the anvil when in the clamped state. The moveable clamp includes a separator feature that generally extends toward the anvil. Each of the first grounding electrode and second grounding electrodes may be configured to translate between a clamped state and an unclamped state. When in themore » clamped state, each of the first and second grounding electrodes is configured to urge a pair of the plurality of stator wire end pairs against the separator feature.« less

Motorcycle helmet effectiveness in reducing head, face and brain injuries by state and helmet law.

PubMed

Olsen, Cody S; Thomas, Andrea M; Singleton, Michael; Gaichas, Anna M; Smith, Tracy J; Smith, Gary A; Peng, Justin; Bauer, Michael J; Qu, Ming; Yeager, Denise; Kerns, Timothy; Burch, Cynthia; Cook, Lawrence J

2016-12-01

Despite evidence that motorcycle helmets reduce morbidity and mortality, helmet laws and rates of helmet use vary by state in the U.S. We pooled data from eleven states: five with universal laws requiring all motorcyclists to wear a helmet, and six with partial laws requiring only a subset of motorcyclists to wear a helmet. Data were combined in the Crash Outcome Data Evaluation System's General Use Model and included motorcycle crash records probabilistically linked to emergency department and inpatient discharges for years 2005-2008. Medical outcomes were compared between partial and universal helmet law settings. We estimated adjusted relative risks (RR) and 95 % confidence intervals (CIs) for head, facial, traumatic brain, and moderate to severe head/facial injuries associated with helmet use within each helmet law setting using generalized log-binomial regression. Reported helmet use was higher in universal law states (88 % vs. 42 %). Median charges, adjusted for inflation and differences in state-incomes, were higher in partial law states (emergency department $1987 vs. $1443; inpatient $31,506 vs. $25,949). Injuries to the head and face, including traumatic brain injuries, were more common in partial law states. Effectiveness estimates of helmet use were higher in partial law states (adjusted-RR (CI) of head injury: 2.1 (1.9-2.2) partial law single vehicle; 1.4 (1.2, 1.6) universal law single vehicle; 1.8 (1.6-2.0) partial law multi-vehicle; 1.2 (1.1-1.4) universal law multi-vehicle). Medical charges and rates of head, facial, and brain injuries among motorcyclists were lower in universal law states. Helmets were effective in reducing injury in both helmet law settings; lower effectiveness estimates were observed in universal law states.

Motorcycle helmet effectiveness in reducing head, face and brain injuries by state and helmet law.

PubMed

Olsen, Cody S; Thomas, Andrea M; Singleton, Michael; Gaichas, Anna M; Smith, Tracy J; Smith, Gary A; Peng, Justin; Bauer, Michael J; Qu, Ming; Yeager, Denise; Kerns, Timothy; Burch, Cynthia; Cook, Lawrence J

Despite evidence that motorcycle helmets reduce morbidity and mortality, helmet laws and rates of helmet use vary by state in the U.S. We pooled data from eleven states: five with universal laws requiring all motorcyclists to wear a helmet, and six with partial laws requiring only a subset of motorcyclists to wear a helmet. Data were combined in the Crash Outcome Data Evaluation System's General Use Model and included motorcycle crash records probabilistically linked to emergency department and inpatient discharges for years 2005-2008. Medical outcomes were compared between partial and universal helmet law settings. We estimated adjusted relative risks (RR) and 95 % confidence intervals (CIs) for head, facial, traumatic brain, and moderate to severe head/facial injuries associated with helmet use within each helmet law setting using generalized log-binomial regression. Reported helmet use was higher in universal law states (88 % vs. 42 %). Median charges, adjusted for inflation and differences in state-incomes, were higher in partial law states (emergency department $1987 vs. $1443; inpatient $31,506 vs. $25,949). Injuries to the head and face, including traumatic brain injuries, were more common in partial law states. Effectiveness estimates of helmet use were higher in partial law states (adjusted-RR (CI) of head injury: 2.1 (1.9-2.2) partial law single vehicle; 1.4 (1.2, 1.6) universal law single vehicle; 1.8 (1.6-2.0) partial law multi-vehicle; 1.2 (1.1-1.4) universal law multi-vehicle). Medical charges and rates of head, facial, and brain injuries among motorcyclists were lower in universal law states. Helmets were effective in reducing injury in both helmet law settings; lower effectiveness estimates were observed in universal law states.

Environmental Assessment for Selected Capital Improvement Plan (CIP) Projects

DTIC Science & Technology

2009-01-01

the USACE Wetlands Delineation Manual as ”those areas that are inundated or saturated by surface or ground water at a frequency and duration... potential for a conventional water supply (Air Force 2000a). Due to its proximity to the Back River and the Chesapeake Bay, and its low ground elevation...coincide, even partially, in time would tend to offer a higher potential for cumulative effects . To identify cumulative effects , this EA addresses three

Enhancement of short-pulse recombination-pumped gain by soft-x-ray photoionization of the ground state

NASA Astrophysics Data System (ADS)

Apruzese, J. P.; Umstadter, D.

1996-02-01

The gain achieved in lasing to the ground state following short-pulse field ionization by a pump laser is highly transient. It will usually persist for only tens of picoseconds because of the rapid filling and negligible emptying of the ground state. Employing a detailed atomic model of lasing in hydrogen, we show that the removal of ground-state population by an appropriate broadband ionizing radiation field can enhance and prolong the gain in such a laser.

Effect of temperature on the single-particle ground-state energy of a polar quantum dot with Gaussian confinement

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jahan, Luhluh K., E-mail: luhluhjahan@gmail.com; Chatterjee, Ashok

2016-05-23

The temperature and size dependence of the ground-state energy of a polaron in a Gaussian quantum dot have been investigated by using a variational technique. It is found that the ground-state energy increases with increasing temperature and decreases with the size of the quantum dot. Also, it is found that the ground-state energy is larger for a three-dimensional quantum dot as compared to a two-dimensional dot.

Water Absorption in Galactic Translucent Clouds: Conditions and History of the Gas Derived from Herschel/HIFI PRISMAS Observations

NASA Astrophysics Data System (ADS)

Flagey, N.; Goldsmith, P. F.; Lis, D. C.; Gerin, M.; Neufeld, D.; Sonnentrucker, P.; De Luca, M.; Godard, B.; Goicoechea, J. R.; Monje, R.; Phillips, T. G.

2013-01-01

We present Herschel/HIFI observations of the three ground state transitions of H2O (556, 1669, and 1113 GHz) and H218O (547, 1655, and 1101 GHz)—as well as the first few excited transitions of H2O (987, 752, and 1661 GHz)—toward six high-mass star-forming regions, obtained as part of the PRISMAS (PRobing InterStellar Molecules with Absorption line Studies) Guaranteed Time Key Program. Water vapor associated with the translucent clouds in Galactic arms is detected in absorption along every line of sight in all the ground state transitions. The continuum sources all exhibit broad water features in emission in the excited and ground state transitions. Strong absorption features associated with the source are also observed at all frequencies except 752 GHz. We model the background continuum and line emission to infer the optical depth of each translucent cloud along the lines of sight. We derive the column density of H2O or H218O for the lower energy level of each transition observed. The total column density of water in translucent clouds is usually about a few 1013 cm-2. We find that the abundance of water relative to hydrogen nuclei is 1 × 10-8 in agreement with models for oxygen chemistry in which high cosmic ray ionization rates are assumed. Relative to molecular hydrogen, the abundance of water is remarkably constant through the Galactic plane with X(H2O) =5 × 10-8, which makes water a good traced of H2 in translucent clouds. Observations of the excited transitions of H2O enable us to constrain the abundance of water in excited levels to be at most 15%, implying that the excitation temperature, T ex, in the ground state transitions is below 10 K. Further analysis of the column densities derived from the two ortho ground state transitions indicates that T ex ~= 5 K and that the density n(H2) in the translucent clouds is below 104 cm-3. We derive the water ortho-to-para ratio for each absorption feature along the line of sight and find that most of the clouds show ratios consistent with the value of 3 expected in thermodynamic equilibrium in the high-temperature limit. However, two clouds with large column densities exhibit a ratio that is significantly below 3. This may argue that the history of water molecules includes a cold phase, either when the molecules were formed on cold grains in the well-shielded, low-temperature regions of the clouds, or when they later become at least partially thermalized with the cold gas (~25 K) in those regions; evidently, they have not yet fully thermalized with the warmer (~50 K) translucent portions of the clouds. Herschel is an ESA space observatory with science instruments provided by European-led Principal Investigator consortia and with important participation from NASA.

Shellwise Mackay transformation in iron nanoclusters.

PubMed

Rollmann, Georg; Gruner, Markus E; Hucht, Alfred; Meyer, Ralf; Entel, Peter; Tiago, Murilo L; Chelikowsky, James R

2007-08-24

Structure and magnetism of iron clusters with up to 641 atoms have been investigated by means of density functional theory calculations including full geometric optimizations. Body-centered cubic (bcc) isomers are found to be lowest in energy when the clusters contain more than about 100 atoms. In addition, another stable conformation has been identified for magic-number clusters, which lies well within the range of thermal energies as compared to the bcc isomers. Its structure is characterized by a close-packed particle core and an icosahedral surface, while intermediate shells are partially transformed along the Mackay path between icosahedral and cuboctahedral geometry. The gradual transformation results in a favorable bcc environment for the subsurface atoms. For Fe55, the shellwise Mackay-transformed morphology is a promising candidate for the ground state.

{Γ}-Convergence Analysis of a Generalized XY Model: Fractional Vortices and String Defects

NASA Astrophysics Data System (ADS)

Badal, Rufat; Cicalese, Marco; De Luca, Lucia; Ponsiglione, Marcello

2018-03-01

We propose and analyze a generalized two dimensional XY model, whose interaction potential has n weighted wells, describing corresponding symmetries of the system. As the lattice spacing vanishes, we derive by {Γ}-convergence the discrete-to-continuum limit of this model. In the energy regime we deal with, the asymptotic ground states exhibit fractional vortices, connected by string defects. The {Γ}-limit takes into account both contributions, through a renormalized energy, depending on the configuration of fractional vortices, and a surface energy, proportional to the length of the strings. Our model describes in a simple way several topological singularities arising in Physics and Materials Science. Among them, disclinations and string defects in liquid crystals, fractional vortices and domain walls in micromagnetics, partial dislocations and stacking faults in crystal plasticity.

Water Resources Data for Alaska, Water Year 1996

USGS Publications Warehouse

Linn, K.R.; Shaw, S.K.; Swanner, W.C.; Rickman, R.L.; Schellekens, M.F.

1997-01-01

Water resources data for the 1996 water year for Alaska consist of records of stage, discharge, and water quality of streams; stages of lakes; and water levels and water quality of ground water. This volume contains records for water discharge at 85 gaging stations; stage or contents only at 5 gaging stations; water quality at 19 gaging stations; and water levels for 49 observation wells. Also included are data for 56 crest-stage partial-record stations and 2 lakes. Additional water data were collected at various sites not involved in the systematic data-collection program and are published as miscellaneous measurements and analyses. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State and Federal agencies in Alaska.

Water resources data, Kansas, water year 2004

USGS Publications Warehouse

Putnam, J.E.; Schneider, D.R.

2005-01-01

Water-resources data for the 2004 water year for Kansas consist of records of stage, discharge, and water quality of streams; elevation and contents of lakes and reservoirs; and water levels of ground-water wells. This report contains records for water discharge at 155 complete-record gaging stations; elevation and contents at 17 lakes and reservoirs; water-quality records at 2 precipitation stations, water-level data at 14 observation wells; and records of specific conductance, pH, water temperature, dissolved oxygen, and turbidity at 16 gaging stations and 2 lakes with water-quality monitors. Also included are discharge data for 29 high-flow partial-record stations. These data represent that part of the National Water Information System collected by the U.S. Geological Survey in cooperation with local, State, and Federal agencies in Kansas.

Habitat Suitability Index Models and Instream Flow Suitability Curves: American shad

USGS Publications Warehouse

Stier, David J.; Crance, Johnie H.

1985-01-01

INTRODUCTION The American shad, an anadromous species, is the largest member of the herring family (Clupeidae) and is native to North America (Talbot and Sykes 1958; Hildebrand 1963; Walburg and Nichols 1967). Historically, the commercial fishery for American shad on the Atlantic coast was widespread and intense; in 1896 the estimated catch was 22.7 million kg (50 million lb). By 1960, however, the estimated catch had dropped to slightly more than 3.6 million kg (8 million lb), according to Walburg and Nichols (1967). Pollution, overfishing, and dams constructed across streams that prevent shad from reaching their spawning grounds have caused partial or total depletion of stocks (Hildebrand 1963). Several programs aimed at restoring American shad to their former range have been initiated by Federal and State agencies.

Water Resources Data, Alaska, Water Year 2000

USGS Publications Warehouse

Meyer, D.F.; Hess, D.L.; Schellekens, M.F.; Smith, C.W.; Snyder, E.F.; Solin, G.L.

2001-01-01

Water-resources data for the 2000 water year for Alaska consists of records of stage, discharge, and water quality of streams; stages of lakes; and water levels and water quality of ground-water wells. This volume contains records for water discharge at 106 gaging stations; stage or contents only at 4 gaging stations; water quality at 31 gaging stations; and water levels for 30 observation wells and 1 water-quality well. Also included are data for 47 crest-stage partial-record stations. Additional water data were collected at various sites not involved in the systematic data-collection program and are published as miscellaneous measurements and analyses. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State and Federal agencies in Alaska.

Electron correlations in partially filled lowest and excited Landau levels

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wojs, Arkadiusz

2001-03-15

The electron correlations near the half-filling of the lowest and excited Landau levels (LL's) are studied using numerical diagonalization. It is shown that in the low-lying states electrons avoid pair states with relative angular momenta R corresponding to positive anharmonicity of the interaction pseudopotential V(R). In the lowest LL, the superharmonic behavior of V(R) causes Laughlin correlations (avoiding pairs with R=1) and the Laughlin-Jain series of incompressible ground states. In the first excited LL, V(R) is harmonic at short range and a different series of incompressible states results. Similar correlations occur in the paired Moore-Read {nu}=5/2 state and in themore » {nu}=7/3 and 8/3 states, all having small total parentage from R=1 and 3 and large parentage from R=5. The {nu}=7/3 and 8/3 states are different from Laughlin {nu}=1/3 and 2/3 states and, in finite systems, occur at a different LL degeneracy (flux). The series of Laughlin-correlated states of electron pairs at {nu}=2+2/(q{sub 2}+2)=8/3, 5/2, 12/5, and 7/3 is proposed, although only in the {nu}=5/2 state pairing has been confirmed numerically. In the second excited LL, V(R) is subharmonic at short range and (near the half-filling) the electrons group into spatially separated larger {nu}=1 droplets to minimize the number of strongly repulsive pair states at R=3 and 5.« less

Analytical approach to the multi-state lasing phenomenon in quantum dot lasers

NASA Astrophysics Data System (ADS)

Korenev, V. V.; Savelyev, A. V.; Zhukov, A. E.; Omelchenko, A. V.; Maximov, M. V.

2013-03-01

We introduce an analytical approach to describe the multi-state lasing phenomenon in quantum dot lasers. We show that the key parameter is the hole-to-electron capture rate ratio. If it is lower than a certain critical value, the complete quenching of ground-state lasing takes place at high injection levels. At higher values of the ratio, the model predicts saturation of the ground-state power. This explains the diversity of experimental results and their contradiction to the conventional rate equation model. Recently found enhancement of ground-state lasing in p-doped samples and temperature dependence of the ground-state power are also discussed.

Structure Effect of Squarylium Cyanine Dyes on Third-Order Optical Nonlinearities in Ground and Excited States

NASA Astrophysics Data System (ADS)

Liu, Xu-chun; Xu, Gang; Si, Jin-hai; Ye, Pei-xian; Lin, Tong; Peng, Bi-xian

1999-08-01

A series of squarylium cyanine dyes with different substituents were synthesized and the third-order optical nonlinearities of their ground and excited states were investigated by backward degenerate four-wave-mixing. For the ground state, the molecular hyperpolarizability γg increases with the red-shift of the absorption peak λmaxab of the squaraine with different substituents, whereas for the excited-state molecular hyperpolarizability γe, the nonlinear enhancement γe/γg decreases, which may indicate that in the excited state the electron accepting-donating ability of different substituents changes in the reverse order compared with the order in the ground state.

Ground and excited states of CaSH through electron propagator calculations

NASA Astrophysics Data System (ADS)

Ortiz, J. V.

1990-05-01

Electron propagator calculations of electron affinities of CaSH + produce ground and excited state energies at the optimized, C s minimum of the neutral ground state and at a C ∞v geometry. Feynman-Dyson amplitudes (FDAs) describe the distribution of the least bound electron in various states. The neutral ground state differs from the cation by the occupation of a one-electron state dominated by Ca s functions. Described by FDAs with Ca-S π pseudosymmetry, corresponding excited states have unpaired electrons in orbitals displaying interference between Ca p and d functions. Above these lies a σ pseudosymmetry FDA with principal contributions from Ca d functions. Two FDAs with σ pseudosymmetry follow. Higher excited states exhibit considerable delocalization onto S.

How Single-site Mutation Affects HP Lattice Proteins

NASA Astrophysics Data System (ADS)

Shi, Guangjie; Landau, David P.; Vogel, Thomas; Wüst, Thomas; Li, Ying Wai

2014-03-01

We developed a heuristic method based on Wang-Landauand multicanonical sampling for determining the ground-state degeneracy of HP lattice proteins . Our algorithm allowed the most precise estimations of the (sometimes substantial) ground-state degeneracies of some widely studied HP sequences. We investigated the effects of single-site mutation on specific long HP lattice proteins comprehensively, including structural changes in ground-states, changes of ground-state degeneracy and thermodynamic properties of the systems. Both extremely sensitive and insensitive cases have been observed; consequently, properties such as specific heat, tortuosities etc. may be either largely unaffected or may change significantly due to mutation. More interestingly, mutation can even induce a lower ground-state energy in a few cases. Supported by NSF.

Documentation of a finite-element two-layer model for simulation of ground-water flow

USGS Publications Warehouse

Mallory, Michael J.

1979-01-01

This report documents a finite-element model for simulation of ground-water flow in a two-aquifer system where the two aquifers are coupled by a leakage term that represents flow through a confining layer separating the two aquifers. The model was developed by Timothy J. Durbin (U.S. Geological Survey) for use in ground-water investigations in southern California. The documentation assumes that the reader is familiar with the physics of ground-water flow, numerical methods of solving partial-differential equations, and the FORTRAN IV computer language. It was prepared as part of the investigations made by the U.S. Geological Survey in cooperation with the San Bernardino Valley Municipal Water District. (Kosco-USGS)

The concave cusp as a determiner of figure-ground.

PubMed

Stevens, K A; Brookes, A

1988-01-01

The tendency to interpret as figure, relative to background, those regions that are lighter, smaller, and, especially, more convex is well known. Wherever convex opaque objects abut or partially occlude one another in an image, the points of contact between the silhouettes form concave cusps, each indicating the local assignment of figure versus ground across the contour segments. It is proposed that this local geometric feature is a preattentive determiner of figure-ground perception and that it contributes to the previously observed tendency for convexity preference. Evidence is presented that figure-ground assignment can be determined solely on the basis of the concave cusp feature, and that the salience of the cusp derives from local geometry and not from adjacent contour convexity.

Stat3 phosphorylation is required for embryonic stem cells ground state maintenance in 2i culture media.

PubMed

Wang, Dan; Sang, Hui; Zhang, Kaiyue; Nie, Yan; Zhao, Shuang; Zhang, Yan; He, Ningning; Wang, Yuebing; Xu, Yang; Xie, Xiaoyan; Li, Zongjin; Liu, Na

2017-05-09

Embryonic stem cells (ES cells) can be maintained its undifferentiated state with feeder cells or LIF, which can activate Jak/Stat3 pathway. Recently, it has been reported a new culture condition comprising serum-free medium with ERK and GSK3β inhibitors (2i) could drive ES cells into a state of pluripotency more like inner cell mass (ICM) in mouse blastocysts called ground state. However, although 2i could sustain ES cells self-renewal, LIF is routinely added. The roles of Stat3 activation are still unclear now. Here we investigated whether Jak/Stat3 might also contribute to the induction of ground state pluripotency. We introduced a lentiviral construct with 7-repeat Stat3-binding sequence to drive Renilla luciferase into ES cells, which can be used as a reporter to detect Stat3 activation by noninvasive bioluminescence imaging. Using this ES cells, we investigated the role of Stat3 activation in ground state maintenance. The results showed that Stat3 could be activated by 2i. Stattic, a chemical inhibitor of Stat3 phosphorylation, could effectively inhibit Stat3 activation in ES cells. When Stat3 activation was suppressed, ground state related genes were down regulated, and ES cells could not be maintained the ground state pluripotency even in 2i medium. All of these results indicate Stat3 activation is required in ground state maintenance.

Solving Quantum Ground-State Problems with Nuclear Magnetic Resonance

PubMed Central

Li, Zhaokai; Yung, Man-Hong; Chen, Hongwei; Lu, Dawei; Whitfield, James D.; Peng, Xinhua; Aspuru-Guzik, Alán; Du, Jiangfeng

2011-01-01

Quantum ground-state problems are computationally hard problems for general many-body Hamiltonians; there is no classical or quantum algorithm known to be able to solve them efficiently. Nevertheless, if a trial wavefunction approximating the ground state is available, as often happens for many problems in physics and chemistry, a quantum computer could employ this trial wavefunction to project the ground state by means of the phase estimation algorithm (PEA). We performed an experimental realization of this idea by implementing a variational-wavefunction approach to solve the ground-state problem of the Heisenberg spin model with an NMR quantum simulator. Our iterative phase estimation procedure yields a high accuracy for the eigenenergies (to the 10−5 decimal digit). The ground-state fidelity was distilled to be more than 80%, and the singlet-to-triplet switching near the critical field is reliably captured. This result shows that quantum simulators can better leverage classical trial wave functions than classical computers PMID:22355607

Effects of temperature on the ground state of a strongly-coupling magnetic polaron and mean phonon number in RbCl quantum pseudodot

NASA Astrophysics Data System (ADS)

Sun, Yong; Ding, Zhao-Hua; Xiao, Jing-Lin

2016-07-01

On the condition of strong electron-LO phonon coupling in a RbCl quantum pseudodot (QPD), the ground state energy and the mean number of phonons are calculated by using the Pekar variational method and quantum statistical theory. The variations of the ground state energy and the mean number with respect to the temperature and the cyclotron frequency of the magnetic field are studied in detail. We find that the absolute value of the ground state energy increases (decreases) with increasing temperature when the temperature is in the lower (higher) temperature region, and that the mean number increases with increasing temperature. The absolute value of the ground state energy is a decreasing function of the cyclotron frequency of the magnetic field whereas the mean number is an increasing function of it. We find two ways to tune the ground state energy and the mean number: controlling the temperature and controlling the cyclotron frequency of the magnetic field.

Identification of ground-state spin ordering in antiferromagnetic transition metal oxides using the Ising model and a genetic algorithm

PubMed Central

Lee, Kyuhyun; Youn, Yong; Han, Seungwu

2017-01-01

Abstract We identify ground-state collinear spin ordering in various antiferromagnetic transition metal oxides by constructing the Ising model from first-principles results and applying a genetic algorithm to find its minimum energy state. The present method can correctly reproduce the ground state of well-known antiferromagnetic oxides such as NiO, Fe2O3, Cr2O3 and MnO2. Furthermore, we identify the ground-state spin ordering in more complicated materials such as Mn3O4 and CoCr2O4. PMID:28458746

Quantum Hall Electron Nematics

NASA Astrophysics Data System (ADS)

MacDonald, Allan

In 2D electron systems hosted by crystals with hexagonal symmetry, electron nematic phases with spontaneously broken C3 symmetry are expected to occur in the quantum Hall regime when triplets of Landau levels associated with three different Fermi surface pockets are partially filled. The broken symmetry state is driven by intravalley Coulombic exchange interactions that favor spontaneously polarized valley occupations. I will discuss three different examples of 2D electron systems in which this type of broken symmetry state is expected to occur: i) the SnTe (111) surface, ii) the Bi (111) surface. and iii) unbalanced bilayer graphene. This type of quantum Hall electron nematic state has so far been confirmed only in the Bi (111) case, in which the anisotropic quasiparticle wavefunctions of the broken symmetry state were directly imaged. In the SnTe case the nematic state phase boundary is controlled by a competition between intravalley Coulomb interactions and intervalley scattering processes that increase in relative strength with magnetic field. An in-plane Zeeman field alters the phase diagram by lifting the three-fold Landau level degeneracy, yielding a ground state energy with 2 π/3 periodicity as a function of Zeeman-field orientation angle. I will comment on the possibility of observing similar states in the absence of a magnetic field. Supported by DOE Division of Materials Sciences and Engineering Grant DE-FG03-02ER45958.

Systematics of α-decay fine structure in odd-mass nuclei based on a finite-range nucleon-nucleon interaction

NASA Astrophysics Data System (ADS)

Adel, A.; Alharbi, T.

2018-07-01

A systematic study on α-decay fine structure is presented for odd-mass nuclei in the range 83 ≤ Z ≤ 92. The α-decay partial half-lives and branching ratios to the ground and excited states of daughter nuclei are calculated in the framework of the Wentzel-Kramers-Brillouin (WKB) approximation with the implementation of the Bohr-Sommerfeld quantization condition. The microscopic α-daughter potential is obtained using the double-folding model with a realistic M3Y-Paris nucleon-nucleon (NN) interaction. The exchange potential, which accounts for the knock-on exchange of nucleons between the interacting nuclei, is calculated using the finite-range exchange NN interaction which is essentially a much better approximation as compared to the zero-range pseudo-potential adopted in the usual double-folding calculations. Our calculations of α-decay fine structure have been improved by considering the preformation factor extracted from the recently proposed cluster formation model on basis of the binding energy difference. The computed partial half-lives and branching ratios are compared with the recent experimental data and they are in good agreement.

Water Resources Data, New Jersey, Water Year 2003; Volume 1. Surface-Water Data

USGS Publications Warehouse

Reed, T.J.; White, B.T.; Centinaro, G.L.; Dudek, J.F.; Protz, A.R.; Shvanda, J.C.; Watson, A.F.

2004-01-01

Water-resources data for the 2003 Water Year for New Jersey are presented in three volumes, and consists of records of stage, discharge, and water quality of streams; stage and contents of lakes and reservoirs; and water levels and water quality of ground water. Volume 1 contains discharge records for 100 gaging stations; tide summaries at 29 tidal gaging stations; and stage and contents at 39 lakes and reservoirs. Also included are stage and discharge for 106 crest-stage partial-record stations, stage-only at 33 tidal crest-stage gages, and discharge for 142 low-flow partial- record stations. Locations of these sites are shown in figures 8-11. Additional discharge measurements were made at 143 miscellaneous sites that are not part of the systematic data-collection program. Discontinued station tables for gaging stations, crest-stage gages, tidal crest-stage and tidal gaging stations show historical coverage. The data in this report represent that part of the National Water Information System (NWIS) data collected by the United States Geological Survey (USGS). Hydrologic conditions are also described for this water year, including streamflow, precipitation, reservoir conditions, and air temperatures.

Water resources data, New Jersey, water year 2005. Volume 1 - surface-water data

USGS Publications Warehouse

White, B.T.; Hoppe, H.L.; Centinaro, G.L.; Dudek, J.F.; Painter, B.S.; Protz, A.R.; Reed, T.J.; Shvanda, J.C.; Watson, A.F.

2006-01-01

Water-resources data for the 2005 water year for New Jersey are presented in three volumes, and consists of records of stage, discharge, and water-quality of streams; stage and contents of lakes and reservoirs; and water levels and water-quality of ground water. Volume 1 contains discharge records for 103 gaging stations; tide summaries at 28 tidal gaging stations; stage and contents at 34 lakes and reservoirs; and diversions from 50 surface-water sources. Also included are stage and discharge for 116 crest-stage partial-record stations, stage-only at 33 tidal crest-stage gages, and discharge for 155 low-flow partial-record stations. Locations of these sites are shown in figures 8-11. Additional discharge measurements were made at 222 miscellaneous sites that are not part of the systematic data-collection program. Discontinued station tables for gaging stations, crest-stage gages, tidal crest-stage and tidal gaging stations show historical coverage. The data in this report represent that part of the National Water Information System (NWIS) data collected by the United States Geological Survey (USGS). Hydrologic conditions are also described for this water year, including stream-flow, precipitation, reservoir conditions, and air temperatures.

Water resources data, New Jersey, water year 2004-volume 1. surface-water data

USGS Publications Warehouse

Centinaro, G.L.; White, B.T.; Hoppe, H.L.; Dudek, J.F.; Protz, A.R.; Reed, T.J.; Shvanda, J.C.; Watson, A.F.

2005-01-01

Water-resources data for the 2004 water year for New Jersey are presented in three volumes, and consists of records of stage, discharge, and water-quality of streams; stage and contents of lakes and reservoirs; and water levels and water-quality of ground water. Volume 1 contains discharge records for 105 gaging stations; tide summaries at 27 tidal gaging stations; stage and contents at 39 lakes and reservoirs; and diversions from 51 surface-water sources. Also included are stage and discharge for 108 crest-stage partial-record stations, stage-only at 34 tidal crest-stage gages, and discharge for 124 low-flow partial-record stations. Locations of these sites are shown in figures 8-11. Additional discharge measurements were made at 131 miscellaneous sites that are not part of the systematic data-collection program. Discontinued station tables for gaging stations, crest-stage gages, tidal crest-stage and tidal gaging stations show historical coverage. The data in this report represent that part of the National Water Information System (NWIS) data collected by the United States Geological Survey (USGS). Hydrologic conditions are also described for this water year, including stream-flow, precipitation, reservoir conditions, and air temperatures.

Partially filled Landau level at even denominators: A vortex metal with a Berry phase

NASA Astrophysics Data System (ADS)

You, Yizhi

2018-04-01

We develop a vortex metal theory for a partially filled Landau level at ν =1/2 n whose ground state contains a composite Fermi surface formed by the vortex of electrons. In the projected Landau-level limit, the composite Fermi surface contains a -π/n Berry phase. Such a fractional Berry phase is a consequence of Landau-level projection which produces the Girvin-MacDonald-Platzman [S. M. Girvin, A. H. MacDonald, and P. M. Platzman, Phys. Rev. B 33, 2481 (1986), 10.1103/PhysRevB.33.2481] guiding center algebra and embellishes an anomalous velocity to the equation of motion for the vortex metal. Further, we investigate a particle-hole symmetric bilayer system with ν1=1/2 n and ν2=1 -1/2 n at each layer, and demonstrate that the -π/n Berry phase on the composite Fermi surface leads to the suppression of 2 kf backscattering between the particle-hole partner bilayer, which could be a smoking gun to detect the fractional Berry phase. We also mention various instabilities and competing orders in such bilayer systems, including a Z4 n topological order phase driven by quantum criticality.

Ground state of Ho atoms on Pt(111) metal surfaces: Implications for magnetism

NASA Astrophysics Data System (ADS)

Karbowiak, M.; Rudowicz, C.

2016-05-01

We investigated the ground state of Ho atoms adsorbed on the Pt(111) surface, for which conflicting results exist. The density functional theory (DFT) calculations yielded the Ho ground state as | Jz=±8 > . Interpretation of x-ray absorption spectroscopy and x-ray magnetic circular dichroism spectra and the magnetization curves indicated the ground state as | Jz=±6 > . Superposition model is employed to predict the crystal-field (CF) parameters based on the structural data for the system Ho/Pt(111) obtained from the DFT modeling. Simultaneous diagonalization of the free-ion (HFI) and the trigonal CF Hamiltonian (HCF) within the whole configuration 4 f10 of H o3 + ion was performed. The role of the trigonal CF terms, neglected in the pure uniaxial CF model used previously for interpretation of experimental spectra, is found significant, whereas the sixth-rank CF terms may be neglected in agreement with the DFT predictions. The results provide substantial support for the experimental designation of the | Jz=±6 > ground state, albeit with subtle difference due to admixture of other | Jz> states, but run against the DFT-based designation of the | Jz=±8 > ground state. A subtle splitting of the ground energy level with the state (predominantly), | Jz=±6 > is predicted. This paper provides better insight into the single-ion magnetic behavior of the Ho/Pt(111) system by helping to resolve the controversy concerning the Ho ground state. Experimental techniques with greater resolution powers are suggested for direct confirmation of this splitting and C3 v symmetry experienced by the Ho atom.

The unfolding effects on the protein hydration shell and partial molar volume: a computational study.

PubMed

Del Galdo, Sara; Amadei, Andrea

2016-10-12

In this paper we apply the computational analysis recently proposed by our group to characterize the solvation properties of a native protein in aqueous solution, and to four model aqueous solutions of globular proteins in their unfolded states thus characterizing the protein unfolded state hydration shell and quantitatively evaluating the protein unfolded state partial molar volumes. Moreover, by using both the native and unfolded protein partial molar volumes, we obtain the corresponding variations (unfolding partial molar volumes) to be compared with the available experimental estimates. We also reconstruct the temperature and pressure dependence of the unfolding partial molar volume of Myoglobin dissecting the structural and hydration effects involved in the process.

Water resources data for Kansas, water year 1973; Part 2, Water quality records

USGS Publications Warehouse

Diaz, A.M.; Albert, C.D.

1974-01-01

Water-resources data for the 1973 water year for Kansas include records of data for the chemical and physical characteristics of surface and ground water. Data on the quality of surface water (chemical, microbiological, temperature, and sediment) were collected from designated sampling sites at predetermined intervals such as once daily, weekly, monthly, or less frequently, and at some sites data were recorded on punched paper tape at 60-minute intervals. Records are given for 70 sampling stations of which 7 are partial-record stations, and for 51 miscellaneous sites. Miscellaneous temperatures of streamflow are given for 77 gaging stations, and records of chemical analyses are given for 224 ground-water sites. Locations of surface water-quality stations are shown in Figure 1, page 2. Records for pertinent water-quality stations in bordering States are also included. The records were collected by the Water Resources Division of the U.S. Geological Survey under the direction of C. W. Lane, district chief. These data represent that portion of the National Water Data System collected by the U.S. Geological Survey and cooperating State and Federal agencies in Kansas. Kansas District personnel who contributed significantly to the collection and preparation of data included in this report were: B. L. Day, L. R. Shelton, M. L. Penny, L. R. Stringer, and D. J. Dark (Kansas State Department of Health).The Geological Survey has published records of chemical quality, suspended sediment, and water temperatures since 1941 in annual series of water-supply papers entitled, "Quality of Surface Waters of the United States." Beginning with the 1964 water year, water-quality records also have been released by the Geological Survey in annual reports on a State-boundary basis. Distribution of these reports is limited; they are designed primarily for rapid release of data shortly after the end of the water year to meet local needs. These records will be published later in Geological Survey water-supply papers.

Gapless Spin-Liquid Ground State in the S =1 /2 Kagome Antiferromagnet

NASA Astrophysics Data System (ADS)

Liao, H. J.; Xie, Z. Y.; Chen, J.; Liu, Z. Y.; Xie, H. D.; Huang, R. Z.; Normand, B.; Xiang, T.

2017-03-01

The defining problem in frustrated quantum magnetism, the ground state of the nearest-neighbor S =1 /2 antiferromagnetic Heisenberg model on the kagome lattice, has defied all theoretical and numerical methods employed to date. We apply the formalism of tensor-network states, specifically the method of projected entangled simplex states, which combines infinite system size with a correct accounting for multipartite entanglement. By studying the ground-state energy, the finite magnetic order appearing at finite tensor bond dimensions, and the effects of a next-nearest-neighbor coupling, we demonstrate that the ground state is a gapless spin liquid. We discuss the comparison with other numerical studies and the physical interpretation of this result.

Ground State Structure of a Coupled 2-Fermion System in Supersymmetric Quantum Mechanics

NASA Astrophysics Data System (ADS)

Finster, Felix

1997-05-01

We prove the uniqueness of the ground state for a supersymmetric quantum mechanical system of two fermions and two bosons, which is closely related to theN=1 WZ-model. The proof is constructive and gives detailed information on what the ground state looks like

Integrating Language and Cognition in Grounded Adaptive Agents

DTIC Science & Technology

2008-11-21

a gents w ill b e able t o communicate amo ng th emselves a nd w ith humans w ith the fl exibility and complexity of h uman language. Leonid...Cangelosi A., Hourdakis E . & Tikhanoff V. (2006). Language acquisition and symbol grounding transfer with neural networks and cognitive robots...Hence it is natural to define the following partial similarity measure between object i and concept k ieO ( ) ( )[∏ = − −−= d e keiekeke OSkil 1

The impact of forest structure on near-ground temperatures during two years of contrasting temperature extremes

Treesearch

Brian E. Potter; Ronald M. Teclaw; John C. Zasada

2001-01-01

The thermal environment of clear-cut, partially cut, and uncut forest sites in northern Wisconsin are examined for a warm year and a cool year. Temperatures at 0.5 m above and 0.05m below ground, as well as base 5 degree C heat sums are computed for each site between May and September and differences between cut and uncut sites compared for the 2 years. differences in...

Gaussian intrinsic entanglement for states with partial minimum uncertainty

NASA Astrophysics Data System (ADS)

Mišta, Ladislav; Baksová, Klára

2018-01-01

We develop a recently proposed theory of a quantifier of bipartite Gaussian entanglement called Gaussian intrinsic entanglement (GIE) [L. Mišta, Jr. and R. Tatham, Phys. Rev. Lett. 117, 240505 (2016), 10.1103/PhysRevLett.117.240505]. Gaussian intrinsic entanglement provides a compromise between computable and physically meaningful entanglement quantifiers and so far it has been calculated for two-mode Gaussian states including all symmetric partial minimum-uncertainty states, weakly mixed asymmetric squeezed thermal states with partial minimum uncertainty, and weakly mixed symmetric squeezed thermal states. We improve the method of derivation of GIE and show that all previously derived formulas for GIE of weakly mixed states in fact hold for states with higher mixedness. In addition, we derive analytical formulas for GIE for several other classes of two-mode Gaussian states with partial minimum uncertainty. Finally, we show that, like for all previously known states, also for all currently considered states the GIE is equal to Gaussian Rényi-2 entanglement of formation. This finding strengthens a conjecture about the equivalence of GIE and Gaussian Rényi-2 entanglement of formation for all bipartite Gaussian states.

Acid whey powder modification of gari from cassava

DOE Office of Scientific and Technical Information (OSTI.GOV)

Okezie, B.O.; Kosikowski, F.V.

1981-01-01

Gari, a staple food consumed in Nigeria, is made from peeled and ground cassava tubers. The ground material is pressed with a stone slab for 2-4 days to remove moisture, and the partially fermented product is then baked over an open fire. Since gari mainly contributes energy to the diet, attempts were made to develop a more nutritious product without altering organoleptic and textural properties. In laboratory tests, ground cassava was fermented in stainless steel cheese vats for 4 days (to produce gari flavour) and then partially dehydrated by pressing in cheese cloth. A reduction in HCN content from 6.2more » to 3.4 mg/100 g resulted. Various combinations of spray-dried acid whey, soya protein and freeze-dried Candida tropicalis were added to the fermented cassava, which was then pressure-cooked for 10 minutes at 121 degrees Celcius, dried and ground in a hammer mill. Product (i), made with gari fortified with 15% soya concentrate and 5% dried acid whey, was as acceptable as traditional gari and had a protein score of 75.8 vs. 9.91 for traditional gari. Product (ii), gari fortified with 20% yeast and 10% dried acid whey, had significantly lower scores for flavour and texture than traditional gari and the protein score was only 29.45. Supplementing gari with relatively inexpensive whey concentrates appears to be a means of overcoming protein energy malnutrition in children.« less

Ground-water recharge in humid areas of the United States: A summary of Ground-Water Resources Program studies, 2003-2006

USGS Publications Warehouse

Delin, Geoffrey N.; Risser, Dennis W.

2007-01-01

Increased demands on water resources by a growing population and recent droughts have raised awareness about the adequacy of ground-water resources in humid areas of the United States. The spatial and temporal variability of ground-water recharge are key factors that need to be quantified to determine the sustainability of ground-water resources. Ground-water recharge is defined herein as the entry into the saturated zone of water made available at the water-table surface, together with the associated flow away from the water table within the saturated zone (Freeze and Cherry, 1979). In response to the need for better estimates of ground-water recharge, the Ground-Water Resources Program (GWRP) of the U.S. Geological Survey (USGS) began an initiative in 2003 to estimate ground-water recharge rates in the relatively humid areas of the United States.

Occurrence of selected herbicides and herbicide degradation products in Iowa's Ground Water, 1995

USGS Publications Warehouse

Kolpin, D.W.; Kalkhoff, S.J.; Goolsby, D.A.; Sneck-Fahrer, D. A.; Thurman, E.M.

1997-01-01

The occurrence of herbicide compounds had a significant, inverse relation to well depth and a significant, positive relation to dissolved-oxygen concentration. It is felt that both well depth and dissolved oxygen are acting as rough surrogates to ground-water age, with younger ground water being more likely to contain herbicide compounds. The occurrence of herbicide compounds was substantially different among the major aquifer types across Iowa, being detected in 82.5% of the alluvial, 81.8% of the bedrock/ karst region, 40.0% of the glacial-drift, and 25.0% of the bedrock/nonkarst region aquifers. The observed distribution was partially attributed to variations in general ground-water age among these aquifer types. A significant, inverse relation was determined between total herbicide compound concentrations in ground water and the average soil slope within a 2-km radius of sampled wells. Steeper soil slopes may increase the likelihood of surface runoff occurring rather than ground-water infiltration–decreasing the transport of herbicide compounds to ground water. As expected, a significant positive relation was determined between intensity of herbicide use and herbicide concentrations in ground water.

Bistable mixed-valence molecular architectures for bit storage

NASA Astrophysics Data System (ADS)

Guihery, Nathalie; Durand, Gérard; Lepetit, Marie-Bernadette

1994-05-01

The work examines the possible realization of bit storage at the molecular scale using mixed valence compounds i.e. the existence of two stable and degenerate forms associated with the 0 and 1 positions of the bit. The proposed systems are constituted of two donors (D) and acceptor (A), or one donor and two acceptors, juxtaposed in DAD or ADA architectures. Our proposals take advantage of the possibility of donor—acceptor complexes to exhibit either complete or partial charge transfer. The first system we propose has an essentially neutral ground state. However, the potential energy surface (PES) presents two degenerated minima associated with a partial charge transfer between the donor and one of the two acceptor molecules (A δ-D δ+1 A and AD δ+ A δ-). Systems presenting a complete charge transfer give rise to two stable, weakly coupled, and degenerate ionic electronic states, A - A + A and AD + A - for an ADA architecture and D + A -D and DA -D + for a DAD In these cases, the two forms differ by both their intramolecular geometries and the relative positions of their constituents. It seems rather difficult to conceive such bistable molecular systems using closed-shell molecules, while a donor radical and a closed-shell acceptor or an acceptor radical and closed-shell donor can generate very stable ionic states. It is assumed that the relative positions of the donor and acceptor molecules can be fixed using chemical bridges constituted of rigid or flexible ligands. The writing and reading processes are discussed for each system as well as the information stability when a large number of bits are juxtaposed on a surface.

Molecular spectroscopy for producing ultracold ground-state NaRb molecules

NASA Astrophysics Data System (ADS)

Wang, Dajun; Guo, Mingyang; Zhu, Bing; Lu, Bo; Ye, Xin; Wang, Fudong; Vexiau, Romain; Bouloufa-Maafa, Nadia; Quéméner, Goulven; Dulieu, Olivier

2016-05-01

Recently, we have successfully created an ultracold sample of absolute ground-state NaRb molecules by two-photon Raman transfer of weakly bound Feshbach molecules. Here we will present the detailed spectroscopic investigations on both the excited and the rovibrational ground states for finding the two-photon path. For the excited state, we focus on the A1Σ+ /b3 Π singlet and triplet admixture. We discovered an anomalously strong coupling between the Ω =0+ and 0- components which renders efficient population transfer possible. In the ground state, the pure nuclear hyperfine levels have been clearly resolved, which allows us to create molecules in the absolute ground state directly with Raman transfer. This work is jointly supported by Agence Nationale de la Recherche (#ANR-13- IS04-0004-01) and Hong Kong Research Grant Council (#A-CUHK403/13) through the COPOMOL project.

Theoretical Study of Tautomerization Reactions for the Ground and First Excited Electronic States of Adenine

NASA Technical Reports Server (NTRS)

Salter, Latasha M.; Chaban, Galina M.; Kwak, Dochan (Technical Monitor)

2002-01-01

Geometrical structures and energetic properties for different tautomers of adenine are calculated in this study, using multi-configurational wave functions. Both the ground and the lowest singlet excited state potential energy surfaces are studied. Four tautomeric forms are considered, and their energetic order is found to be different on the ground and the excited state potential energy surfaces. Minimum energy reaction paths are obtained for hydrogen atom transfer (tautomerization) reactions in the ground and the lowest excited electronic states. It is found that the barrier heights and the shapes of the reaction paths are different for the ground and the excited electronic states, suggesting that the probability of such tautomerization reaction is higher on the excited state potential energy surface. This tautomerization process should become possible in the presence of water or other polar solvent molecules and should play an important role in the photochemistry of adenine.

Studies on the corrosion resistance of reinforced steel in concrete with ground granulated blast-furnace slag--An overview.

PubMed

Song, Ha-Won; Saraswathy, Velu

2006-11-16

The partial replacement of clinker, the main constituent of ordinary Portland cement by pozzolanic or latent hydraulic industrial by-products such as ground granulated blast furnace slag (GGBFS), effectively lowers the cost of cement by saving energy in the production process. It also reduces CO2 emissions from the cement plant and offers a low priced solution to the environmental problem of depositing industrial wastes. The utilization of GGBFS as partial replacement of Portland cement takes advantage of economic, technical and environmental benefits of this material. Recently offshore, coastal and marine concrete structures were constructed using GGBFS concrete because high volume of GGBFS can contribute to the reduction of chloride ingress. In this paper, the influence of using GGBFS in reinforced concrete structures from the durability aspects such as chloride ingress and corrosion resistance, long term durability, microstructure and porosity of GGBFS concrete has been reviewed and discussed.

Properties of iron sulfide, hydrosulfide, and mixed sulfide/hydrosulfide cluster anions through photoelectron spectroscopy and density functional theory calculations.

PubMed

Yin, Shi; Bernstein, Elliot R

2016-10-21

A new magnetic-bottle time-of-flight photoelectron spectroscopy (PES) apparatus is constructed in our laboratory. The PES spectra of iron sulfide, hydrosulfide, and mixed sulfide/hydrosulfide [FeS m (SH) n - ; m, n = 0-3, 0 < (m + n) ≤ 3] cluster anions, obtained at 2.331 eV (532 nm) and 3.492 eV (355 nm) photon energies, are reported. The electronic structure and bonding properties of these clusters are additionally investigated at different levels of density functional theory. The most probable structures and ground state spin multiplicity for these cluster anions are tentatively assigned by comparing their theoretical first vertical detachment energies (VDEs) with their respective experiment values. The behavior of S and (SH) as ligands in these iron sulfide, hydrosulfide, and mixed sulfide/hydrosulfide cluster anions is investigated and compared. The experimental first VDEs for Fe(SH) 1-3 - cluster anions are lower than those found for their respective FeS 1-3 - cluster anions. The experimental first VDEs for FeS 1-3 - clusters are observed to increase for the first two S atoms bound to Fe - ; however, due to the formation of an S-S bond for the FeS 3 - cluster, its first VDE is found to be ∼0.41 eV lower than the first VDE for the FeS 2 - cluster. The first VDEs of Fe(SH) 1-3 - cluster anions are observed to increase with the increasing numbers of SH groups. The calculated partial charges of the Fe atom for ground state FeS 1-3 - and Fe(SH) 1-3 - clusters are apparently related to and correlated with their determined first VDEs. The higher first VDE is correlated with a higher, more positive partial charge for the Fe atom of these cluster anions. Iron sulfide/hydrosulfide mixed cluster anions are also explored in this work: the first VDE for FeS(SH) - is lower than that for FeS 2 - , but higher than that for Fe(SH) 2 - ; the first VDEs for FeS 2 (SH) - and FeS(SH) 2 - are close to that for FeS 3 - , but higher than that for Fe(SH) 3 - . The first VDEs of general iron sulfide, hydrosulfide, and mixed sulfide/hydrosulfide clusters [FeS m (SH) n - ; m, n = 0-3, 0 < (m + n) ≤ 3] are dependent on three properties of these anions: 1. the partial charge on the Fe atom, 2. disulfide bond formation (S-S) in the cluster, and 3. the number of hydrosulfide ligands in the cluster. The higher the partial charge on the Fe atom of these clusters, the larger the first VDE; however, cluster S-S bonding and more (SH) ligands in the cluster lower the cluster anion first VDE.

Properties of iron sulfide, hydrosulfide, and mixed sulfide/hydrosulfide cluster anions through photoelectron spectroscopy and density functional theory calculations

NASA Astrophysics Data System (ADS)

Yin, Shi; Bernstein, Elliot R.

2016-10-01

A new magnetic-bottle time-of-flight photoelectron spectroscopy (PES) apparatus is constructed in our laboratory. The PES spectra of iron sulfide, hydrosulfide, and mixed sulfide/hydrosulfide [FeSm(SH)n-; m, n = 0-3, 0 < (m + n) ≤ 3] cluster anions, obtained at 2.331 eV (532 nm) and 3.492 eV (355 nm) photon energies, are reported. The electronic structure and bonding properties of these clusters are additionally investigated at different levels of density functional theory. The most probable structures and ground state spin multiplicity for these cluster anions are tentatively assigned by comparing their theoretical first vertical detachment energies (VDEs) with their respective experiment values. The behavior of S and (SH) as ligands in these iron sulfide, hydrosulfide, and mixed sulfide/hydrosulfide cluster anions is investigated and compared. The experimental first VDEs for Fe(SH)1-3- cluster anions are lower than those found for their respective FeS1-3- cluster anions. The experimental first VDEs for FeS1-3- clusters are observed to increase for the first two S atoms bound to Fe-; however, due to the formation of an S-S bond for the FeS3- cluster, its first VDE is found to be ˜0.41 eV lower than the first VDE for the FeS2- cluster. The first VDEs of Fe(SH)1-3- cluster anions are observed to increase with the increasing numbers of SH groups. The calculated partial charges of the Fe atom for ground state FeS1-3- and Fe(SH)1-3- clusters are apparently related to and correlated with their determined first VDEs. The higher first VDE is correlated with a higher, more positive partial charge for the Fe atom of these cluster anions. Iron sulfide/hydrosulfide mixed cluster anions are also explored in this work: the first VDE for FeS(SH)- is lower than that for FeS2-, but higher than that for Fe(SH)2-; the first VDEs for FeS2(SH)- and FeS(SH)2- are close to that for FeS3-, but higher than that for Fe(SH)3-. The first VDEs of general iron sulfide, hydrosulfide, and mixed sulfide/hydrosulfide clusters [FeSm(SH)n-; m, n = 0-3, 0 < (m + n) ≤ 3] are dependent on three properties of these anions: 1. the partial charge on the Fe atom, 2. disulfide bond formation (S-S) in the cluster, and 3. the number of hydrosulfide ligands in the cluster. The higher the partial charge on the Fe atom of these clusters, the larger the first VDE; however, cluster S-S bonding and more (SH) ligands in the cluster lower the cluster anion first VDE.

Evidence for a low-temperature magnetic ground state in double-perovskite iridates with I r5 +(5 d4) ions

NASA Astrophysics Data System (ADS)

Terzic, J.; Zheng, H.; Ye, Feng; Zhao, H. D.; Schlottmann, P.; De Long, L. E.; Yuan, S. J.; Cao, G.

2017-08-01

We report an unusual magnetic ground state in single-crystal, double-perovskite B a2YIr O6 and Sr-doped B a2YIr O6 with I r5 +(5 d4) ions. Long-range magnetic order below 1.7 K is confirmed by dc magnetization, ac magnetic susceptibility, and heat-capacity measurements. The observed magnetic order is extraordinarily delicate and cannot be explained in terms of either a low-spin S =1 state, or a singlet Jeff=0 state imposed by the spin-orbit interactions (SOI). Alternatively, the magnetic ground state appears consistent with a SOI that competes with comparable Hund's rule coupling and inherently large electron hopping, which cannot stabilize the singlet Jeff=0 ground state. However, this picture is controversial, and conflicting magnetic behavior for these materials is reported in both experimental and theoretical studies, which highlights the intricate interplay of interactions that determine the ground state of materials with strong SOI.

Exact ground states and topological order in interacting Kitaev/Majorana chains

NASA Astrophysics Data System (ADS)

Katsura, Hosho; Schuricht, Dirk; Takahashi, Masahiro

2015-09-01

We study a system of interacting spinless fermions in one dimension that, in the absence of interactions, reduces to the Kitaev chain [Kitaev, Phys. Usp. 44, 131 (2001), 10.1070/1063-7869/44/10S/S29]. In the noninteracting case, a signal of topological order appears as zero-energy modes localized near the edges. We show that the exact ground states can be obtained analytically even in the presence of nearest-neighbor repulsive interactions when the on-site (chemical) potential is tuned to a particular function of the other parameters. As with the noninteracting case, the obtained ground states are twofold degenerate and differ in fermionic parity. We prove the uniqueness of the obtained ground states and show that they can be continuously deformed to the ground states of the noninteracting Kitaev chain without gap closing. We also demonstrate explicitly that there exists a set of operators each of which maps one of the ground states to the other with opposite fermionic parity. These operators can be thought of as an interacting generalization of Majorana edge zero modes.

Real-time observation of intramolecular proton transfer in the electronic ground state of chloromalonaldehyde: an ab initio study of time-resolved photoelectron spectra.

PubMed

do N Varella, Márcio T; Arasaki, Yasuki; Ushiyama, Hiroshi; Takatsuka, Kazuo; Wang, Kwanghsi; McKoy, Vincent

2007-02-07

The authors report on studies of time-resolved photoelectron spectra of intramolecular proton transfer in the ground state of chloromalonaldehyde, employing ab initio photoionization matrix elements and effective potential surfaces of reduced dimensionality, wherein the couplings of proton motion to the other molecular vibrational modes are embedded by averaging over classical trajectories. In the simulations, population is transferred from the vibrational ground state to vibrationally hot wave packets by pumping to an excited electronic state and dumping with a time-delayed pulse. These pump-dump-probe simulations demonstrate that the time-resolved photoelectron spectra track proton transfer in the electronic ground state well and, furthermore, that the geometry dependence of the matrix elements enhances the tracking compared with signals obtained with the Condon approximation. Photoelectron kinetic energy distributions arising from wave packets localized in different basins are also distinguishable and could be understood, as expected, on the basis of the strength of the optical couplings in different regions of the ground state potential surface and the Franck-Condon overlaps of the ground state wave packets with the vibrational eigenstates of the ion potential surface.

High resolution infrared spectroscopy of [1.1.1]propellane: The region of the ν 9 band

DOE Office of Scientific and Technical Information (OSTI.GOV)

Maki, Arthur; Weber, Alfons; Nibler, Joseph W.

2010-11-01

The region of the infrared-active band of the ν 9 CH2 bending mode [1.1.1]propellane has been recorded at a resolution (0.0025 cm -1) sufficient to distinguish individual rovibrational lines. This region includes the partially overlapping bands ν 9 (e') = 1459 cm -1, 2ν 18 (l = 2, E') = 1430 cm -1, ν 6 + ν 12 (E') = 1489 cm-1, and ν 4 + ν 15 (A 2") = 1518 cm -1. In addition, the difference band ν 4 - ν 15 (A2") was observed in the far infrared near 295 cm -1 and analyzed to give goodmore » constants for the upper ν 4 levels. The close proximities of the four bands in the ν 9 region suggest that Coriolis and Fermi resonance couplings could be significant and theoretical band parameters obtained from Gaussian ab initio calculations were helpful in guiding the band analyses. The analyses of all four bands were accomplished, based on our earlier report of ground state constants determined from combination differences involving more than 4000 pairs of transitions from five fundamental and four combination bands. This paper presents the analyses and the determination of the upper state constants of all four bands in the region of the ν 9 band. Complications were most evident in the 2ν 18 (l = 2, E') band, which showed significant perturbations due to mixing with the nearby 2ν 18 (l = 0, A 1') and ν 4 + ν 12 (E') levels which are either infrared inactive as transitions from the ground state, or, in the latter case, too weak to observe. Finally, these complications are discussed and a comparison of all molecular constants with those available from the ab initio calculations at the anharmonic level is presented.« less

Spin-1/2 Heisenberg antiferromagnet on an anisotropic triangular lattice

NASA Astrophysics Data System (ADS)

Starykh, Oleg

2007-03-01

The Triangular lattice spin-1/2 Heisenberg AntiFerromagnet (TAF) is a prototypical model of frustrated quantum magnetism. While it is believed to exhibit long-range order in the isotropic limit, changes such as spatial anisotropy can alter the delicate balance amongst competing ground states. I will describe the static and dynamic properties of the spatially anisotropic TAF, with inter-chain diagonal exchange J' much weaker than the intrachain exchange J. Treating J' as a perturbation of decoupled Heisenberg spin-1/2 chains, I find that the ground state is spontaneously dimerized in a four-fold degenerate zig-zag pattern. This dimerization instability is driven by quantum fluctuations, which are dramatically enhanced here by the frustrated nature of inter-chain exchange. A magnetic field partially relieves frustration, by canting the spins along the field direction, and causes a quantum phase transition into a magnetically-ordered spin-density-wave phase. This is followed by cone and, finally, fully polarized (saturated) phases, as a function of increasing magnetic field. I show that many of these features are in fact observed in experiments on the celebrated material Cs2CuCl4 (J'/J =1/3). I will also discuss the significant modification of the phase diagram by symmetry-breaking anisotropic Dzyaloshinskii-Moriya (DM) interactions, present in this interesting magnet. In addition to static and thermodynamic properties, the proposed ``one-dimensional'' approach offers a compelling explanation of the unusual experimentally measured dynamical structure factor of Cs2CuCl4 in terms of descendants of one-dimensional spinons. Quite generally, I find characteristic features of a momentum-dependent spinon bound state and a dispersing incoherent excitation in the structure factor, in agreement with experiments.

Ground-water data collected in the Missouri River basin units in Kansas during 1950

USGS Publications Warehouse

Berry, Delmar W.

1951-01-01

Ground-water studies in the Missouri River basin were begun by the United States Geological Survey during the fall of 1945 as a part of a program for the development of the resources of the basin by the United States Bureau of Reclamation and other Federal Agencies. The studies of the ground-water resources in the part of Kansas that lies within the basin have been coordinated with the cooperative program of ground-water studies already being carried on in Kansas by the United States Geological Survey, the State Geological Survey of Kansas,the Division of Sanitation of the Kansas State Board of Health, and the Division of Water Resources of the Kansas State Board of Agriculture.

Nature of ground and electronic excited states of higher acenes

PubMed Central

Yang, Yang; Yang, Weitao

2016-01-01

Higher acenes have drawn much attention as promising organic semiconductors with versatile electronic properties. However, the nature of their ground state and electronic excited states is still not fully clear. Their unusual chemical reactivity and instability are the main obstacles for experimental studies, and the potentially prominent diradical character, which might require a multireference description in such large systems, hinders theoretical investigations. Here, we provide a detailed answer with the particle–particle random-phase approximation calculation. The 1Ag ground states of acenes up to decacene are on the closed-shell side of the diradical continuum, whereas the ground state of undecacene and dodecacene tilts more to the open-shell side with a growing polyradical character. The ground state of all acenes has covalent nature with respect to both short and long axes. The lowest triplet state 3B2u is always above the singlet ground state even though the energy gap could be vanishingly small in the polyacene limit. The bright singlet excited state 1B2u is a zwitterionic state to the short axis. The excited 1Ag state gradually switches from a double-excitation state to another zwitterionic state to the short axis, but always keeps its covalent nature to the long axis. An energy crossing between the 1B2u and excited 1Ag states happens between hexacene and heptacene. Further energetic consideration suggests that higher acenes are likely to undergo singlet fission with a low photovoltaic efficiency; however, the efficiency might be improved if a singlet fission into multiple triplets could be achieved. PMID:27528690

Brake wear warning device: A concept

NASA Technical Reports Server (NTRS)

Hawkins, S. F.

1973-01-01

Heat-insulated wire is introduced through brake shoe and partially into brake lining. Wire is connected to positive terminal and light bulb. When brakes wear to critical point, contact between wire and wheel drum grounds circuit and turns on warning light.

Ground state structure of random magnets

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bastea, S.; Duxbury, P.M.

1998-10-01

Using exact optimization methods, we find all of the ground states of ({plus_minus}h) random-field Ising magnets (RFIM) and of dilute antiferromagnets in a field (DAFF). The degenerate ground states are usually composed of isolated clusters (two-level systems) embedded in a frozen background. We calculate the paramagnetic response (sublattice response) and the ground state entropy for the RFIM (DAFF) due to these clusters. In both two and three dimensions there is a broad regime in which these quantities are strictly positive, even at irrational values of h/J (J is the exchange constant). {copyright} {ital 1998} {ital The American Physical Society}

A molecular-field approximation for quantum crystals. Ph.D. Thesis; [considering ground state properties

NASA Technical Reports Server (NTRS)

Danilowicz, R.

1973-01-01

Ground-state properties of quantum crystals have received considerable attention from both theorists and experimentalists. The theoretical results have varied widely with the Monte Carlo calculations being the most successful. The molecular field approximation yields ground-state properties which agree closely with the Monte Carlo results. This approach evaluates the dynamical behavior of each pair of molecules in the molecular field of the other N-2 molecules. In addition to predicting ground-state properties that agree well with experiment, this approach yields data on the relative importance of interactions of different nearest neighbor pairs.

Analysis of ground state in random bipartite matching

NASA Astrophysics Data System (ADS)

Shi, Gui-Yuan; Kong, Yi-Xiu; Liao, Hao; Zhang, Yi-Cheng

2016-02-01

Bipartite matching problems emerge in many human social phenomena. In this paper, we study the ground state of the Gale-Shapley model, which is the most popular bipartite matching model. We apply the Kuhn-Munkres algorithm to compute the numerical ground state of the model. For the first time, we obtain the number of blocking pairs which is a measure of the system instability. We also show that the number of blocking pairs formed by each person follows a geometric distribution. Furthermore, we study how the connectivity in the bipartite matching problems influences the instability of the ground state.

THE ONCE AND FUTURE AIR SUPPORT OPERATIONS CENTER: A CRITICAL REFLECTION ON DEVELOPMENTS IN AIR-TO-GROUND COMMAND AND CONTROL

DTIC Science & Technology

2017-02-01

call for an examination of ASOC history to provide clear guidance for leaders designing the contemporary ASOC. Research Question What does the...be combined in the design of the future ASOC and what is required to enhance and sustain its capability. 4 Finally, the research concludes by...DEVELOPMENTS IN AIR-TO- GROUND COMMAND AND CONTROL by Seth D. Spidahl, Capt, USAF A Research Report Submitted to the Faculty In Partial Fulfillment

Understanding the Importance and Practice of Credible Leadership at Program Executive Office Ground Combat Systems (PEO GCS) and Program Executive Office Combat Support and Combat Service Support (PEO CS and CSS)

DTIC Science & Technology

2017-03-30

and Program Executive Office Combat Support and Combat Service Support (PEO CS&CSS) Chad P. Stocker March 30, 2017 Submitted to...to Defense Acquisition University in partial fulfillment of the requirement of the Senior Service College Fellowship CREDIBLE LEADERSHIP AT PEO...of Credible Leadership at Program Executive Office Ground Combat Systems (PEO GCS) and Program Executive Office Combat Support and Combat Service

Effect of Different Ground Scenarios on Flow Structure of a Rotor At Hover Condition

NASA Astrophysics Data System (ADS)

Kocak, Goktug; Nalbantoglu, Volkan; Yavuz, Mehmet Metin

2017-11-01

The ground effect of a scaled model rotor at hover condition was investigated experimentally in a confined environment. Different ground effect scenarios including full, partial, and inclined conditions, compared to out of ground condition, were characterized qualitatively and quantitatively using laser illuminated smoke visualization and Laser Doppler Anemometry measurements. The results indicate that the presence of the ground affects the flow regime near the blade tip by changing the spatial extent and the path of the vortex core. After the impingement of the wake to the ground, highly unsteady and turbulent wake is observed. Both the mean and the root mean square of the induced velocity increase toward the blade tip. In line with this, the spectral power of the dominant frequency in the velocity fluctuations significantly increases toward the blade tip. All these observations are witnessed in all ground effect conditions tested in the present study. Considering the inclined ground effect in particular, it is observed that the mean induced velocities of the high side (mountain) are higher compared to the velocities of the low side (valley) in contrast to the general trend observed in the present study where the ground effect reduces the induced velocity.

Amodal completion of moving objects by pigeons.

PubMed

Nagasaka, Yasuo; Wasserman, Edward A

2008-01-01

In a series of four experiments, we explored whether pigeons complete partially occluded moving shapes. Four pigeons were trained to discriminate between a complete moving shape and an incomplete moving shape in a two-alternative forced-choice task. In testing, the birds were presented with a partially occluded moving shape. In experiment 1, none of the pigeons appeared to complete the testing stimulus; instead, they appeared to perceive the testing stimulus as incomplete fragments. However, in experiments 2, 3, and 4, three of the birds appeared to complete the partially occluded moving shapes. These rare positive results suggest that motion may facilitate amodal completion by pigeons, perhaps by enhancing the figure - ground segregation process.

Luminorefrigeration: vibrational cooling of NaCs.

PubMed

Wakim, A; Zabawa, P; Haruza, M; Bigelow, N P

2012-07-02

We demonstrate the use of optical pumping of kinetically ultracold NaCs to cool an initial vibrational distribution of electronic ground state molecules X(1)Σ(+)(v ≥ 4) into the vibrational ground state X(1)Σ(+)(v=0). Our approach is based on the use of simple, commercially available multimode diode lasers selected to optically pump population into X(1)Σ(+)(v=0). We investigate the impact of the cooling process on the rotational state distribution of the vibrational ground state, and observe that an initial distribution, J(initial)=0-2 is only moderately affected resulting in J(final)=0-4. This method provides an inexpensive approach to creation of vibrational ground state ultracold polar molecules.

Heat of formation determination of the ground and excited state of cyanomethylene (HCCN) radical

NASA Technical Reports Server (NTRS)

Francisco, Joseph S.

1994-01-01

Ab initio electronic structure theory has been used to characterize the structure of the ground triplet and lowest singlet excited states of cyanomethylene. The geometries, vibrational frequencies, and heats of formation have been determined using second-order Moller-Plesset perturbation, single and double excitation configuration interaction, and quadratic configuration interaction theory. The heat of formation is predicted with isodesmic reaction and Gaussian-2 theory (G2) for the ground triplet and first excited singlet states of cyanomethylene. For the ground state Delta-H(sub 0)(sup f,0) is 114.8+/-2 kcal/mol while for the excited single state it is 126.5+/-2 kcal/mol.

Guide to Louisiana's ground-water resources

USGS Publications Warehouse

Stuart, C.G.; Knochenmus, D.D.; McGee, B.D.

1994-01-01

Ground water is one of the most valuable and abundant natural resources of Louisiana. Of the 4-.4 million people who live in the State, 61 percent use ground water as a source for drinking water. Most industrial and rural users and half of the irrigation users in the State rely on ground water. Quantity, however, is not the only aspect that makes ground water so valuable; quality also is important for its use. In most areas, little or no water treatment is required for drinking water and industrial purposes. Knowledge of Louisiana's ground-water resources is needed to ensure proper development and protection of this valuable resource. This report is designed to inform citizens about the availability and quality of ground water in Louisiana. It is not intended as a technical reference; rather, it is a guide to ground water and the significant role this resource plays in the state. Most of the ground water that is used in the State is withdrawn from 13 aquifers and aquifer systems: the Cockfield, Sparta, and Carrizo-Wilcox aquifersin northern Louisiana; Chicot aquifer system, Evangeline aquifer, Jasper aquifer system, and Catahoula aquifer in central and southwestern Louisiana; the Chicot equivalent, Evangeline equivalent, and Jasper equivalent aquifer systems in southeastern Louisiana; and the MississippiRiver alluvial, Red River alluvial, and upland terrace aquifers that are statewide. Ground water is affected by man's activities on the land surface, and the major ground-water concerns in Louisiana are: (1) contamination from surface disposal of hazardous waste, agricultural chemicals, and petroleum products; (2) contamination from surface wastes and saltwater through abandoned wells; (3) saltwater encroachment; and (4) local overdevelopment. Information about ground water in Louisiana is extensive and available to the public. Several State and Federal agencies provide published and unpublished material upon request.

Fermions in Two Dimensions: Scattering and Many-Body Properties

DOE PAGES

Galea, Alexander; Zielinski, Tash; Gandolfi, Stefano; ...

2017-08-10

Ultracold atomic Fermi gases in two dimensions (2D) are an increasingly popular topic of research. The interaction strength between spin-up and spin-down particles in two-component Fermi gases can be tuned in experiments, allowing for a strongly interacting regime where the gas properties are yet to be fully understood. We have probed this regime for 2D Fermi gases by performing T = 0 ab initio diffusion Monte Carlo calculations. The many-body dynamics are largely dependent on the two-body interactions; therefore, we start with an in-depth look at scattering theory in 2D. We show the partial-wave expansion and its relation to themore » scattering length and effective range. Then, we discuss our numerical methods for determining these scattering parameters. Here, we close out this discussion by illustrating the details of bound states in 2D. Transitioning to the many-body system, we also use variationally optimized wave functions to calculate ground-state properties of the gas over a range of interaction strengths. We show results for the energy per particle and parametrize an equation of state. We then proceed to determine the chemical potential for the strongly interacting gas.« less

Fermions in Two Dimensions: Scattering and Many-Body Properties

DOE Office of Scientific and Technical Information (OSTI.GOV)

Galea, Alexander; Zielinski, Tash; Gandolfi, Stefano

Ultracold atomic Fermi gases in two dimensions (2D) are an increasingly popular topic of research. The interaction strength between spin-up and spin-down particles in two-component Fermi gases can be tuned in experiments, allowing for a strongly interacting regime where the gas properties are yet to be fully understood. We have probed this regime for 2D Fermi gases by performing T = 0 ab initio diffusion Monte Carlo calculations. The many-body dynamics are largely dependent on the two-body interactions; therefore, we start with an in-depth look at scattering theory in 2D. We show the partial-wave expansion and its relation to themore » scattering length and effective range. Then, we discuss our numerical methods for determining these scattering parameters. Here, we close out this discussion by illustrating the details of bound states in 2D. Transitioning to the many-body system, we also use variationally optimized wave functions to calculate ground-state properties of the gas over a range of interaction strengths. We show results for the energy per particle and parametrize an equation of state. We then proceed to determine the chemical potential for the strongly interacting gas.« less

Studies on the structural stability of Co2P2O7 under pressure

NASA Astrophysics Data System (ADS)

Wang, W. P.; Pang, H.; Jin, M. L.; Shen, X.; Yao, Y.; Wang, Y. G.; Li, Y. C.; Li, X. D.; Jin, C. Q.; Yu, R. C.

2018-05-01

The crystal structural evolution of Co2P2O7 was studied by using in situ high pressure angle dispersive x-ray diffraction with synchrotron radiation. The results demonstrate that the α phase of Co2P2O7 goes through a partially irreversible structural transformation to β phase under pressure. The pressure is conductive to reduce the longest Cosbnd O bond length of the α phase, and then more uniform Cosbnd O bonds and regular hexagonal arrangement of CoO6 octahedra of the β phase are favored. According to the Birch-Murnaghan equation, the fitted bulk modulus B0 is 158.1(±5.6) GPa for α phase and 276.5(±6.5) GPa for β phase. Furthermore, the first-principles calculations show that these two phases of Co2P2O7 have almost equal total energies, and also have similar band structures and spin-polarized density of states at their ground states. This may be the reason why these two phases of Co2P2O7 can coexist in the pressure released state. It is found that the band gap energies decrease with increasing pressure for both phases.

The resonant structure of ^18Ne and its relevance in the breakout of the Hot CNO cycle

NASA Astrophysics Data System (ADS)

Almaraz-Calderon, S.; Tan, W.; Aprahamian, A.; Bucher, B.; Gorres, J.; Roberts, A.; Villano, A.; Wiescher, M.; Brune, C.; Heinen, Z.; Massey, T.; Mach, H.; Guray, N.; Guray, R. T.

2009-10-01

In explosive hydrogen burning environments such as Novae and X-ray bursts, temperatures and densities achieved are sufficiently high to bypass the beta decay of the waiting points of the hot CNO cycle by alpha captures, leading to a thermonuclear runaway via the rp-process. One of the two paths to a breakout from the hot CNO cycle is the route starting from ^14O(α,p)^17F followed by ^17F(p,γ)^18Ne and ^18Ne(α,p). The ^14O(α,p) reaction proceeds through resonant states in ^18Ne, making the reaction rate dependent on the excitation energies and spins as well as partial and total widths of these resonances. We used the ^16O(^3He,n) reaction and charged particle-neutron coincidences to measure the structure details of levels in ^18Ne. In particular, the α and proton decay branching ratios via ground state and excited states in ^17F were measured. The analysis of the data will allow us to provide crucial information to be included in the reaction network calculations that could have great impact on the nuclear energy generation and nucleosynthesis that occur in these explosive environments.

State and territorial use of ground-water strategy grant funds (Section 106 Clean Water Act). Technical report (Final)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1987-05-01

This document reports on the activities of States in FY 85 and 86 in developing and implementing State ground-water protection strategies using Clean Water Act Section 106 funds. Every State and all but one territory has participated in the program. Strategies have included emphasis on the need to consolidate State and local agency efforts, and to provide clear policy direction, greater public awareness and education concerning ground-water protection.

Toward Triplet Ground State NaLi Molecules

NASA Astrophysics Data System (ADS)

Ebadi, Sepehr; Jamison, Alan; Rvachov, Timur; Jing, Li; Son, Hyungmok; Jiang, Yijun; Zwierlein, Martin; Ketterle, Wolfgang

2016-05-01

The NaLi molecule is expected to have a long lifetime in the triplet ground-state due to its fermionic nature, large rotational constant, and weak spin-orbit coupling. The triplet state has both electric and magnetic dipole moments, affording unique opportunities in quantum simulation and ultracold chemistry. We have mapped the excited state NaLi triplet potential by means of photoassociation spectroscopy. We report on this and our further progress toward the creation of the triplet ground-state molecules using STIRAP. NSF, ARO-MURI, Samsung, NSERC.

Semistable extremal ground states for nonlinear evolution equations in unbounded domains

NASA Astrophysics Data System (ADS)

Rodríguez-Bernal, Aníbal; Vidal-López, Alejandro

2008-02-01

In this paper we show that dissipative reaction-diffusion equations in unbounded domains posses extremal semistable ground states equilibria, which bound asymptotically the global dynamics. Uniqueness of such positive ground state and their approximation by extremal equilibria in bounded domains is also studied. The results are then applied to the important case of logistic equations.

Framework for a ground-water quality monitoring and assessment program for California

USGS Publications Warehouse

Belitz, Kenneth; Dubrovsky, Neil M.; Burow, Karen; Jurgens, Bryant C.; John, Tyler

2003-01-01

The State of California uses more ground water than any other State in the Nation. With a population of over 30 million people, an agricultural economy based on intensive irrigation, large urban industrial areas, and naturally elevated concentrations of some trace elements, there is a wide range of contaminant sources that have the potential to contaminate ground water and limit its beneficial uses. In response to the many-and different-potential sources of ground-water contamination, the State of California has evolved an extensive set of rules and programs to protect ground-water quality, and agencies to implement the rules and programs. These programs have in common a focus on compliance with regulations governing chemical use and (or) ground-water quality. Although appropriate for, and successful at, their specific missions, these programs do not at present provide a comprehensive view of ground-water quality in the State of California. In October 2001, The California Assembly passed a bill, AB 599, establishing the Ground-Water- Quality Monitoring Act of 2001.' The goal of AB 599 is to improve Statewide comprehensive ground-water monitoring and increase availability of information about ground-water quality to the public. AB 599 requires the State Water Resources Control Board (SWRCB), in collaboration with an interagency task force (ITF) and a public advisory committee (PAC), to develop a plan for a comprehensive ground-water monitoring program. AB 599 specifies that the comprehensive program should be capable of assessing each ground-water basin in the State through direct and other statistically reliable sampling approaches, and that the program should integrate existing monitoring programs and design new program elements, as necessary. AB 599 also stresses the importance of prioritizing ground-water basins that provide drinking water. The United States Geological Survey (USGS), in cooperation with the SWRCB, and in coordination with the ITF and PAC, has developed a framework for a comprehensive ground-water-quality monitoring and assessment program for California. The proposed framework relies extensively on previous work conducted by the USGS through its National Water-Quality Assessment (NAWQA) program. In particular, the NAWQA program defines three types of ground-water assessment: (1) status, the assessment of the current quality of the ground-water resource; (2) trends, the detection of changes in water quality, and (3) understanding, assessing the human and natural factors that affect ground-water quality. A Statewide, comprehensive ground-water quality-monitoring and assessment program is most efficiently accomplished by applying uniform and consistent study-design and data-collection protocols to the entire State. At the same time, a comprehensive program should be relevant at a variety of scales, and therefore needs to retain flexibility to address regional and local issues. Consequently, many of the program components include a predominant element that will be consistently applied in all basins, and a secondary element that may be applied in specific basins where local conditions warrant attention.

Optimization modeling to maximize population access to comprehensive stroke centers

PubMed Central

Branas, Charles C.; Kasner, Scott E.; Wolff, Catherine; Williams, Justin C.; Albright, Karen C.; Carr, Brendan G.

2015-01-01

Objective: The location of comprehensive stroke centers (CSCs) is critical to ensuring rapid access to acute stroke therapies; we conducted a population-level virtual trial simulating change in access to CSCs using optimization modeling to selectively convert primary stroke centers (PSCs) to CSCs. Methods: Up to 20 certified PSCs per state were selected for conversion to maximize the population with 60-minute CSC access by ground and air. Access was compared across states based on region and the presence of state-level emergency medical service policies preferentially routing patients to stroke centers. Results: In 2010, there were 811 Joint Commission PSCs and 0 CSCs in the United States. Of the US population, 65.8% had 60-minute ground access to PSCs. After adding up to 20 optimally located CSCs per state, 63.1% of the US population had 60-minute ground access and 86.0% had 60-minute ground/air access to a CSC. Across states, median CSC access was 55.7% by ground (interquartile range 35.7%–71.5%) and 85.3% by ground/air (interquartile range 59.8%–92.1%). Ground access was lower in Stroke Belt states compared with non–Stroke Belt states (32.0% vs 58.6%, p = 0.02) and lower in states without emergency medical service routing policies (52.7% vs 68.3%, p = 0.04). Conclusion: Optimal system simulation can be used to develop efficient care systems that maximize accessibility. Under optimal conditions, a large proportion of the US population will be unable to access a CSC within 60 minutes. PMID:25740858

Optimization modeling to maximize population access to comprehensive stroke centers.

PubMed

Mullen, Michael T; Branas, Charles C; Kasner, Scott E; Wolff, Catherine; Williams, Justin C; Albright, Karen C; Carr, Brendan G

2015-03-24

The location of comprehensive stroke centers (CSCs) is critical to ensuring rapid access to acute stroke therapies; we conducted a population-level virtual trial simulating change in access to CSCs using optimization modeling to selectively convert primary stroke centers (PSCs) to CSCs. Up to 20 certified PSCs per state were selected for conversion to maximize the population with 60-minute CSC access by ground and air. Access was compared across states based on region and the presence of state-level emergency medical service policies preferentially routing patients to stroke centers. In 2010, there were 811 Joint Commission PSCs and 0 CSCs in the United States. Of the US population, 65.8% had 60-minute ground access to PSCs. After adding up to 20 optimally located CSCs per state, 63.1% of the US population had 60-minute ground access and 86.0% had 60-minute ground/air access to a CSC. Across states, median CSC access was 55.7% by ground (interquartile range 35.7%-71.5%) and 85.3% by ground/air (interquartile range 59.8%-92.1%). Ground access was lower in Stroke Belt states compared with non-Stroke Belt states (32.0% vs 58.6%, p = 0.02) and lower in states without emergency medical service routing policies (52.7% vs 68.3%, p = 0.04). Optimal system simulation can be used to develop efficient care systems that maximize accessibility. Under optimal conditions, a large proportion of the US population will be unable to access a CSC within 60 minutes. © 2015 American Academy of Neurology.

Antibonding ground state of adatom molecules in bulk Dirac semimetals

NASA Astrophysics Data System (ADS)

Marques, Y.; Obispo, A. E.; Ricco, L. S.; de Souza, M.; Shelykh, I. A.; Seridonio, A. C.

2017-07-01

The ground state of the diatomic molecules in nature is inevitably bonding, and its first excited state is antibonding. We demonstrate theoretically that, for a pair of distant adatoms placed buried in three-dimensional-Dirac semimetals, this natural order of the states can be reversed and an antibonding ground state occurs at the lowest energy of the so-called bound states in the continuum. We propose an experimental protocol with the use of a scanning tunneling microscope tip to visualize the topographic map of the local density of states on the surface of the system to reveal the emerging physics.

Water Resources Data, Louisiana, Water Year 2002

USGS Publications Warehouse

Goree, B.B.; Lovelace, W.M.; Montgomery, P.A.; Resweber, J.C.; Labbe, Charles K.; Walters, David J.

2003-01-01

Water resources data for the 2002 water year for Louisiana consists of records of stage, discharge, and water quality of streams; stage, contents, and water quality of lakes and reservoirs; and water levels and water quality of ground water. This report contains records for water discharge at 85 gaging stations; stage only for 79 gaging stations and 7 lakes; water quality for 52 surface-water stations (including 40 gaging stations) and 104 wells; and water levels for 300 observation wells. Also included are data for 143 crest-stage and flood-profile partial-record stations. Additional water data were collected at various sites not included in the systematic data-collection program, and are published as miscellaneous measurements. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State and Federal agencies in Louisiana.

Water Resources Data, Kansas, Water Year 2001

USGS Publications Warehouse

Putnam, J.E.; Lacock, D.L.; Schneider, D.R.

2002-01-01

Water-resources data for the 2001 water year for Kansas consist of records of stage, discharge, and water quality of streams; elevation and contents of lakes and reservoirs; and water levels of ground-water wells. This report contains records for water discharge at 145 complete-record gaging stations; elevation and contents at 20 lakes and reservoirs; waterquality records at 2 precipitation stations, water-level data at 19 observation wells; and records of specific conductance, pH, water temperature, dissolved oxygen, and turbidity at 11 gaging stations. Also included are discharge data for 26 high-flow partial-record stations, miscellaneous onsite water-quality data collected at 140 stations, and suspended-sediment concentration for 12 stations. These data represent that part of the National Water Information System collected by the U.S. Geological Survey in cooperation with local, State, and Federal agencies in Kansas.

Water Resources Data, Kansas, Water Year 2002

USGS Publications Warehouse

Putnam, J.E.; Schneider, D.R.

2003-01-01

Water-resources data for the 2002 water year for Kansas consist of records of stage, discharge, and water quality of streams; elevation and contents of lakes and reservoirs; and water levels of ground-water wells. This report contains records for water discharge at 149 complete-record gaging stations; elevation and contents at 20 lakes and reservoirs; waterquality records at 2 precipitation stations, water-level data at 18 observation wells; and records of specific conductance, pH, water temperature, dissolved oxygen, and turbidity at 11 gaging stations. Also included are discharge data for 26 high-flow partial-record stations, miscellaneous onsite water-quality data collected at 142 stations, and suspended-sediment concentration for 12 stations. These data represent that part of the National Water Information System collected by the U.S. Geological Survey in cooperation with local, State, and Federal agencies in Kansas.

Water Resources Data, Kansas, Water Year 2000

USGS Publications Warehouse

Putnam, J.E.; Lacock, D.L.; Schneider, D.R.; Carlson, M.D.

2001-01-01

Water-resources data for the 2000 water year for Kansas consist of records of stage, discharge, and water quality of streams; elevation and contents of lakes and reservoirs; and water levels of ground-water wells. This report contains records for water discharge at 144 complete-record gaging stations; elevation and contents at 19 lakes and reservoirs; water-quality records at 2 precipitation stations, water-level data at 18 observation wells; and records of specific conductance, pH, water temperature, dissolved oxygen, and turbidity at 8 gaging stations. Also included are discharge data for 26 high-flow partial-record stations, and miscellaneous onsite water-quality data collected at 134 stations, and suspended-sediment concentration for 12 stations. These data represent that part of the National Water Information System collected by the U.S. Geological Survey in cooperation with local, State, and Federal agencies in Kansas.

Water Resources Data, Kansas, Water Year 1999

USGS Publications Warehouse

Putnam, J.E.; Lacock, D.L.; Schneider, D.R.; Carlson, M.D.

2000-01-01

Water-resources data for the 1999 water year for Kansas consist of records of stage, discharge, and water quality of streams; elevation and contents of lakes and reservoirs; and water levels of ground-water wells. This report contains records for water discharge at 143 gaging stations; elevation and contents at 19 watershed lakes and reservoirs; and water-level data at 19 observation wells; and records of specific conductance, pH, water temperature, dissolved oxygen, and turbidity at 4 stations. Also included are data for 26 high-flow and 2 low-flow partial-record stations; and 2 chemical quality of precipitation stations. Miscellaneous onsite water-quality data were collected at 132 stations. These data represent that part of the National Water Information System collected by the U.S. Geological Survey in cooperation with State, local, and Federal agencies in Kansas.

Imaging of molecular hydrogen and oxygen by single and two-photon fluorescence using laser and flashlamp sources

NASA Technical Reports Server (NTRS)

Diskin, Glenn S.; Lempert, Walter R.; Miles, Richard B.; Kumar, Vinod; Glesk, Ivan

1991-01-01

Two flow visualization techniques, i.e., simultaneous two-dimensional fluorescence imaging of H2 and O2 in a diffusion flame, and quasi-linear fluorescence imaging of O2, are presented. The first uses an injection-locked argon-fluoride excimer laser and a partial overlap of a two-photon ground state absorption in H2 with a single photon absorption from a vibrational level in O2. The second uses a simple, high-intensity ultraviolet flashlamp which provides a flux of photons in the 180-195 nm range, sufficient to produce a quasi-one-dimensional fluorescence image of hot/room temperature oxygen. Both techniques do not require that a seed material be introduced into the flow, they can image major flow constituents, and provide an instantaneous snapshot of the flow.

Water resources data, Louisiana, water year 2004

USGS Publications Warehouse

Baumann, Todd; Goree, B.B.; Lovelace, W.M.; Montogmery, P.A.; Resweber, J.C.; Ross, Garron B.; Ward, Aub N.; Walters, David J.

2005-01-01

Water resources data for the 2004 water year for Louisiana consist of records of stage, discharge, and water quality of streams; stage, contents, and water quality of lakes and reservoirs; and water levels and water quality of ground water. This report contains records for water discharge at 77 gaging stations; stage only for 86 gaging stations and 7 lakes; water quality for 60 surface-water stations (including 42 gaging stations) and 112 wells; and water levels for 304 observation wells. Also included are data for 158 crest-stage and flood-profile partial-record stations. Additional water data were collected at various sites not included in the systematic data-collection program, and are published as miscellaneous measurements. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State and Federal agencies in Louisiana.

Quantum chemical calculation (electronic and topologic) and experimental (FT-IR, FT-Raman and UV) analysis of isonicotinic acid N-oxide

NASA Astrophysics Data System (ADS)

Karaca, Caglar; Atac, Ahmet; Karabacak, Mehmet

2015-04-01

In this work, the molecular conformation, vibrational and electronic analysis of isonicotinic acid N-oxide (iso-NANO) were presented in the ground state using experimental techniques (FT-IR, FT-Raman and UV) and density functional theory (DFT) employing B3LYP exchange correlation with the 6-311++G(d,p) basis set. The geometry optimization and energies associated possible two conformers (Rot-I and Rot-II) were computed. The vibrational spectra were calculated and fundamental vibrations were assigned on the basis of the total energy distribution (TED) of the vibrational modes, calculated with scaled quantum mechanics (SQM) method and PQS program. The obtained structures were analyzed with the Atoms in Molecules (AIMs) methodology. The computational results diagnose the most stable conformer of iso-NANO as the Rot-I form. Total density of state (TDOS) and partial density of state (PDOS) and also overlap population density of state (OPDOS) diagrams analysis for the most stable conformer (Rot-I) were calculated using the same method. Thermodynamic properties (heat capacity, entropy and enthalpy) of the title compound at different temperatures were calculated. As a result, the optimized geometry and calculated spectroscopic data show a good agreement with the experimental results.

High-resolution vacuum-ultraviolet photoabsorption spectra of 1-butyne and 2-butyne

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jacovella, U.; Holland, D. M. P.; Boyé-Péronne, S.

2015-07-21

The absolute photoabsorption cross sections of 1- and 2-butyne have been recorded at high resolution by using the vacuum-ultraviolet Fourier-Transform spectrometer at the SOLEIL Synchrotron. Both spectra show more resolved structure than previously observed, especially in the case of 2-butyne. In this work, we assess the potential importance of Rydberg states with higher values of orbital angular momentum, l, than are typically observed in photoabsorption experiments from ground state molecules. We show how the character of the highest occupied molecular orbitals in 1- and 2-butyne suggests the potential importance of transitions to such high-l (l = 3 and 4) Rydbergmore » states. Furthermore, we use theoretical calculations of the partial wave composition of the absorption cross section just above the ionization threshold and the principle of continuity of oscillator strength through an ionization threshold to support this conclusion. The new absolute photoabsorption cross sections are discussed in light of these arguments, and the results are consistent with the expectations. This type of argument should be valuable for assessing the potential importance of different Rydberg series when sufficiently accurate direct quantum chemical calculations are difficult, for example, in the n ≥ 5 manifolds of excited states of larger molecules.« less

Experimental linear-optics simulation of ground-state of an Ising spin chain.

PubMed

Xue, Peng; Zhan, Xian; Bian, Zhihao

2017-05-19

We experimentally demonstrate a photonic quantum simulator: by using a two-spin Ising chain (an isolated dimer) as an example, we encode the wavefunction of the ground state with a pair of entangled photons. The effect of magnetic fields, leading to a critical modification of the correlation between two spins, can be simulated by just local operations. With the ratio of simulated magnetic fields and coupling strength increasing, the ground state of the system changes from a product state to an entangled state and back to another product state. The simulated ground states can be distinguished and the transformations between them can be observed by measuring correlations between photons. This simulation of the Ising model with linear quantum optics opens the door to the future studies which connect quantum information and condensed matter physics.

A transition matrix approach to the Davenport gryo calibration scheme

NASA Technical Reports Server (NTRS)

Natanson, G. A.

1998-01-01

The in-flight gyro calibration scheme commonly used by NASA Goddard Space Flight Center (GSFC) attitude ground support teams closely follows an original version of the Davenport algorithm developed in the late seventies. Its basic idea is to minimize the least-squares differences between attitudes gyro- propagated over the course of a maneuver and those determined using post- maneuver sensor measurements. The paper represents the scheme in a recursive form by combining necessary partials into a rectangular matrix, which is propagated in exactly the same way as a Kalman filters square transition matrix. The nontrivial structure of the propagation matrix arises from the fact that attitude errors are not included in the state vector, and therefore their derivatives with respect to estimated a parameters do not appear in the transition matrix gyro defined in the conventional way. In cases when the required accuracy can be achieved by a single iteration, representation of the Davenport gyro calibration scheme in a recursive form allows one to discard each gyro measurement immediately after it was used to propagate the attitude and state transition matrix. Another advantage of the new approach is that it utilizes the same expression for the error sensitivity matrix as that used by the Kalman filter. As a result the suggested modification of the Davenport algorithm made it possible to reuse software modules implemented in the Kalman filter estimator, where both attitude errors and gyro calibration parameters are included in the state vector. The new approach has been implemented in the ground calibration utilities used to support the Tropical Rainfall Measuring Mission (TRMM). The paper analyzes some preliminary results of gyro calibration performed by the TRMM ground attitude support team. It is demonstrated that an effect of the second iteration on estimated values of calibration parameters is negligibly small, and therefore there is no need to store processed gyro data. This opens a promising opportunity for onboard implementation of the suggested recursive procedure by combining, it with the Kalman filter used to obtain necessary attitude solutions at the beginning and end of each maneuver.

Ground-water management under the appropriation doctrine. Technical report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ralston, D.; Bruhl, E.J.

The purpose of the research is to better understand the characteristics of ground-water management under the prior-appropriation doctrine in the western United States. The general objective is to summarize the legal and administrative controls on ground-water use in eight western states and to compare the impacts of these controls on ground water systems.

Detecting phase boundaries of quantum spin-1/2 XXZ ladder via bipartite and multipartite entanglement transitions

NASA Astrophysics Data System (ADS)

Singha Roy, Sudipto; Dhar, Himadri Shekhar; Rakshit, Debraj; Sen(De), Aditi; Sen, Ujjwal

2017-12-01

Phase transition in quantum many-body systems inevitably causes changes in certain physical properties which then serve as potential indicators of critical phenomena. Besides the traditional order parameters, characterization of quantum entanglement has proven to be a computationally efficient and successful method for detection of phase boundaries, especially in one-dimensional models. Here we determine the rich phase diagram of the ground states of a quantum spin-1/2 XXZ ladder by analyzing the variation of bipartite and multipartite entanglements. Our study characterizes the different ground state phases and notes the correspondence with known results, while highlighting the finer details that emerge from the behavior of ground state entanglement. Analysis of entanglement in the ground state provides a clearer picture of the complex ground state phase diagram of the system using only a moderate-size model.

Ground-state information geometry and quantum criticality in an inhomogeneous spin model

NASA Astrophysics Data System (ADS)

Ma, Yu-Quan

2015-09-01

We investigate the ground-state Riemannian metric and the cyclic quantum distance of an inhomogeneous quantum spin-1/2 chain in a transverse field. This model can be diagonalized by using a general canonical transformation to the fermionic Hamiltonian mapped from the spin system. The ground-state Riemannian metric is derived exactly on a parameter manifold ring S1, which is introduced by performing a gauge transformation to the spin Hamiltonian through a twist operator. The cyclic ground-state quantum distance and the second derivative of the ground-state energy are studied in different exchange coupling parameter regions. Particularly, we show that, in the case of exchange coupling parameter Ja = Jb, the quantum ferromagnetic phase can be characterized by an invariant quantum distance and this distance will decay to zero rapidly in the paramagnetic phase. Project supported by the National Natural Science Foundation of China (Grant Nos. 11404023 and 11347131).

Doped colloidal artificial spin ice

DOE PAGES

Libál, A.; Reichhardt, C. J. Olson; Reichhardt, C.

2015-10-07

We examine square and kagome artificial spin ice for colloids confined in arrays of double-well traps. Conversely, magnetic artificial spin ices, unlike colloidal and vortex artificial spin ice realizations, allow creation of doping sites through double occupation of individual traps. We find that doping square and kagome ice geometries produces opposite effects. For square ice, doping creates local excitations in the ground state configuration that produce a local melting effect as the temperature is raised. In contrast, the kagome ice ground state can absorb the doping charge without generating non-ground-state excitations, while at elevated temperatures the hopping of individual colloidsmore » is suppressed near the doping sites. Our results indicate that in the square ice, doping adds degeneracy to the ordered ground state and creates local weak spots, while in the kagome ice, which has a highly degenerate ground state, doping locally decreases the degeneracy and creates local hard regions.« less

Doped colloidal artificial spin ice

DOE Office of Scientific and Technical Information (OSTI.GOV)

Libál, A.; Reichhardt, C. J. Olson; Reichhardt, C.

We examine square and kagome artificial spin ice for colloids confined in arrays of double-well traps. Conversely, magnetic artificial spin ices, unlike colloidal and vortex artificial spin ice realizations, allow creation of doping sites through double occupation of individual traps. We find that doping square and kagome ice geometries produces opposite effects. For square ice, doping creates local excitations in the ground state configuration that produce a local melting effect as the temperature is raised. In contrast, the kagome ice ground state can absorb the doping charge without generating non-ground-state excitations, while at elevated temperatures the hopping of individual colloidsmore » is suppressed near the doping sites. Our results indicate that in the square ice, doping adds degeneracy to the ordered ground state and creates local weak spots, while in the kagome ice, which has a highly degenerate ground state, doping locally decreases the degeneracy and creates local hard regions.« less

Approximating quantum many-body wave functions using artificial neural networks

NASA Astrophysics Data System (ADS)

Cai, Zi; Liu, Jinguo

2018-01-01

In this paper, we demonstrate the expressibility of artificial neural networks (ANNs) in quantum many-body physics by showing that a feed-forward neural network with a small number of hidden layers can be trained to approximate with high precision the ground states of some notable quantum many-body systems. We consider the one-dimensional free bosons and fermions, spinless fermions on a square lattice away from half-filling, as well as frustrated quantum magnetism with a rapidly oscillating ground-state characteristic function. In the latter case, an ANN with a standard architecture fails, while that with a slightly modified one successfully learns the frustration-induced complex sign rule in the ground state and approximates the ground states with high precisions. As an example of practical use of our method, we also perform the variational method to explore the ground state of an antiferromagnetic J1-J2 Heisenberg model.

Surface-Water Data, Georgia, Water Year 1999

USGS Publications Warehouse

Alhadeff, S. Jack; Landers, Mark N.; McCallum, Brian E.

1999-01-01

Water resources data for the 1999 water year for Georgia consists of records of stage, discharge, and water quality of streams; and the stage and contents of lakes and reservoirs published in one volume in a digital format on a CD-ROM. This volume contains discharge records of 121 gaging stations; stage for 13 gaging stations; stage and contents for 18 lakes and reservoirs; continuous water quality records for 10 stations; and the annual peak stage and annual peak discharge for 75 crest-stage partial-record stations. These data represent that part of the National Water Data System collected by the U.S. Geological Survey and cooperating State and Federal agencies in Georgia. Records of discharge and stage of streams, and contents or stage of lakes and reservoirs were first published in a series of U.S. Geological water-supply papers entitled, 'Surface-Water Supply of the United States.' Through September 30, 1960, these water-supply papers were in an annual series and then in a 5-year series for 1961-65 and 1966-70. Records of chemical quality, water temperature, and suspended sediment were published from 1941 to 1970 in an annual series of water-supply papers entitled, 'Quality of Surface Waters of the United States.' Records of ground-water levels were published from 1935 to 1974 in a series of water-supply papers entitled, 'Ground-Water Levels in the United States.' Water-supply papers may be consulted in the libraries of the principal cities in the United States or may be purchased from the U.S. Geological Survey, Branch of Information Services, Federal Center, Box 25286, Denver, CO 80225. For water years 1961 through 1970, streamflow data were released by the U.S. Geological Survey in annual reports on a State-boundary basis prior to the two 5-year series water-supply papers, which cover this period. The data contained in the water-supply papers are considered the official record. Water-quality records for water years 1964 through 1970 were similarly released either in separate reports or in conjunction with streamflow records. Beginning with the 1971 water year, water data for streamflow, water quality, and ground water are published in official Survey reports on a State-boundary basis. These official Survey reports carry an identification number consisting of the two-letter State abbreviation, the last two digits of the water year, and the volume number. For example, this volume is identified as 'U.S. Geological Survey Water-Data Report GA-99-1.' These water-data reports are for sale in various formats, by the National Technical Information Service, U.S. Department of Commerce, Springfield, VA 22161.

The stability of ground ice in the equatorial region of Mars

NASA Technical Reports Server (NTRS)

Clifford, S. M.; Hillel, D.

1983-01-01

The lifetime of an unreplenished layer of ground ice lying within 30 deg of the Martian equator was examined within the context of the existing data base on Martian regolith and climate. Data on the partial pressure of H2O in the Martian atmosphere and the range of mean annual temperatures indicated the ground ice would be restricted to latitudes poleward of 40 deg. However, the ground ice near the poles may be a relic from early Martian geologic times held in place by a thin layer of regolith. Consideration of twelve model pore size distributions, similar to silt- and clay-type earth soils, was combined with a parallel pore model of gaseous diffusion to calculate the flux of H2O molecules escaping from the subsurface ground ice layer. Martian equatorial ground ice was found to be influenced by the soil structure, the magnitude of the geothermal gradient, the climatic desorption of CO2 from the regolith. It is concluded that equatorial ground ice is present on Mars only if a process of replenishment is active.

The ground-state energy of the ± J sping glass. A comparison of various biologically motivated algorithms

NASA Astrophysics Data System (ADS)

Gropengiesser, Uwe

1995-06-01

We compare various evlutionary strategies to determine the ground-state energy of the ± J spin glass. We show that the choice of different evolution laws is less important than a suitable treatment of the "free spins" of the system At least one combination of these strategies does not give the correct results, but the ground states of the other different strategies coincide. Therefore we are able to extrapolate the infinit-size ground-state energy for the square lattice to -1.401±0.0015 and for the simple cubic lattice to -1.786±0.004.

Fast Preparation of Critical Ground States Using Superluminal Fronts

NASA Astrophysics Data System (ADS)

Agarwal, Kartiek; Bhatt, R. N.; Sondhi, S. L.

2018-05-01

We propose a spatiotemporal quench protocol that allows for the fast preparation of ground states of gapless models with Lorentz invariance. Assuming the system initially resides in the ground state of a corresponding massive model, we show that a superluminally moving "front" that locally quenches the mass, leaves behind it (in space) a state arbitrarily close to the ground state of the gapless model. Importantly, our protocol takes time O (L ) to produce the ground state of a system of size ˜Ld (d spatial dimensions), while a fully adiabatic protocol requires time ˜O (L2) to produce a state with exponential accuracy in L . The physics of the dynamical problem can be understood in terms of relativistic rarefaction of excitations generated by the mass front. We provide proof of concept by solving the proposed quench exactly for a system of free bosons in arbitrary dimensions, and for free fermions in d =1 . We discuss the role of interactions and UV effects on the free-theory idealization, before numerically illustrating the usefulness of the approach via simulations on the quantum Heisenberg spin chain.

Multiconfiguration Pair-Density Functional Theory Outperforms Kohn-Sham Density Functional Theory and Multireference Perturbation Theory for Ground-State and Excited-State Charge Transfer.

PubMed

Ghosh, Soumen; Sonnenberger, Andrew L; Hoyer, Chad E; Truhlar, Donald G; Gagliardi, Laura

2015-08-11

The correct description of charge transfer in ground and excited states is very important for molecular interactions, photochemistry, electrochemistry, and charge transport, but it is very challenging for Kohn-Sham (KS) density functional theory (DFT). KS-DFT exchange-correlation functionals without nonlocal exchange fail to describe both ground- and excited-state charge transfer properly. We have recently proposed a theory called multiconfiguration pair-density functional theory (MC-PDFT), which is based on a combination of multiconfiguration wave function theory with a new type of density functional called an on-top density functional. Here we have used MC-PDFT to study challenging ground- and excited-state charge-transfer processes by using on-top density functionals obtained by translating KS exchange-correlation functionals. For ground-state charge transfer, MC-PDFT performs better than either the PBE exchange-correlation functional or CASPT2 wave function theory. For excited-state charge transfer, MC-PDFT (unlike KS-DFT) shows qualitatively correct behavior at long-range with great improvement in predicted excitation energies.

GROUND-WATER POLLUTION PROBLEMS IN THE SOUTHEASTERN UNITED STATES

EPA Science Inventory

An evaluation of principal sources of ground-water contamination has been carried out in seven southeastern States--Alabama, Florida, Georgia, Mississippi, North Carolina, South Carolina, and Virginia. Natural ground-water quality is good to excellent, except for the presence of ...

78 FR 44890 - Approval and Promulgation of Implementation Plans; North Carolina; Control Techniques Guidelines...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-07-25

... for the 1997 8- hour ozone NAAQS includes six full counties and one partial county in North Carolina; and one partial county in South Carolina. The North Carolina portion of the bi-state Charlotte Area... one full county and six partial counties in the bi-state Charlotte area as a marginal nonattainment...

Order by disorder and gaugelike degeneracy in a quantum pyrochlore antiferromagnet.

PubMed

Henley, Christopher L

2006-02-03

The (three-dimensional) pyrochlore lattice antiferromagnet with Heisenberg spins of large spin length S is a highly frustrated model with a macroscopic degeneracy of classical ground states. The zero-point energy of (harmonic-order) spin-wave fluctuations distinguishes a subset of these states. I derive an approximate but illuminating effective Hamiltonian, acting within the subspace of Ising spin configurations representing the collinear ground states. It consists of products of Ising spins around loops, i.e., has the form of a Z2 lattice gauge theory. The remaining ground-state entropy is still infinite but not extensive, being O(L) for system size O(L3). All these ground states have unit cells bigger than those considered previously.

Probing the 5 f electrons in Am-I by hybrid density functional theory

NASA Astrophysics Data System (ADS)

Atta-Fynn, Raymond; Ray, Asok K.

2009-11-01

The ground states of the actinides and their compounds continue to be matters of considerable controversies. Experimentally, Americium-I (Am-I) is a non-magnetic dhcp metal whereas theoretically an anti-ferromagnetic ground state is predicted. We show that hybrid density functional theory, which admixes a fraction, λ, of exact Hartree-Fock (HF) exchange with approximate DFT exchange, can correctly reproduce the ground state properties of Am. In particular, for λ=0.40, we obtain a non-magnetic ground state with equilibrium atomic volume, bulk modulus, 5 f electron population, and the density of electronic states all in good agreement with experimental data. We argue that the exact HF exchange corrects the overestimation of the approximate DFT exchange interaction.

Ground water in Pavant Valley

USGS Publications Warehouse

Dennis, P. E.; Maxey, G.B.; Thomas, H.E.

1946-01-01

The users of wells for irrigation in Pavant Valley, particularly in the Flowell district, have long been cognizant of their utter dependency upon ground water for livelihood, and were among the first in the State to make an organized effort to conserve supplies by prevention of waste. Since passage of the State ground-water law in 1935, the State Engineer has not approved applications for new wells in the areas of most concentrated development, and has deferred adjudication of existing water rights until adequate data concerning the ground-water resources become available. The investigation of ground-water resources in Pavant Valley was suggested by the State Engineer and constitutes one of a series that are being made in the important groundwater basins of Utah by the Federal Geological Survey in cooperation with the State Engineer. The investigation was under the general supervision of Oscar E. Meinzer, geologist in charge of the ground-water division of the Federal Geological Survey. H. E. Thomas, in charge of groundwater investigations in Utah, returned from military service overseas in time to assist in the completion of the manuscript, and edited the report.

Redefining private insurance in a changing market structure.

PubMed

Chollet, D J

1996-01-01

This discussion on likely changes and challenges for the health insurance industry over the coming decade assumes that significant national reform of health care financing for the privately insured population will not occur--or, if it does, that it will mirror the insurance market reforms that many states already have undertaken. First, the changes in private insurance coverage during the past several years are considered, with particular attention to the erosion of employer-based coverage and to the rising influence of public insurance programs--especially Medicaid--on the private insurance market. Next is a description of the changing web of state laws and regulations governing private health insurance. At this writing, virtually every state has enacted or is considering reforms of the small group market to limit what many perceive as unfair or destructive insurer practices and to set new ground rules for competition among insurance arrangements. The changing nature of private insurance contracts in the United States is considered next. Evolving from conventional fee-for-service contracts, private insurance is increasingly a complex mixture of capitation, partial capitation, and reinsurance of capitated arrangements. Finally, this chapter discusses three issues of increasing importance in shaping the marketplace for private insurers: (1) the federal preemption of states' regulatory authority over self-insured employer plans; (2) emerging state regulation to restructure competition in the health insurance and health care markets; and (3) the growing interest of both federal and state governments in medical savings accounts to finance health insurance and health care spending.

Long-Lived Ultracold Molecules with Electric and Magnetic Dipole Moments.

PubMed

Rvachov, Timur M; Son, Hyungmok; Sommer, Ariel T; Ebadi, Sepehr; Park, Juliana J; Zwierlein, Martin W; Ketterle, Wolfgang; Jamison, Alan O

2017-10-06

We create fermionic dipolar ^{23}Na^{6}Li molecules in their triplet ground state from an ultracold mixture of ^{23}Na and ^{6}Li. Using magnetoassociation across a narrow Feshbach resonance followed by a two-photon stimulated Raman adiabatic passage to the triplet ground state, we produce 3×10^{4} ground state molecules in a spin-polarized state. We observe a lifetime of 4.6 s in an isolated molecular sample, approaching the p-wave universal rate limit. Electron spin resonance spectroscopy of the triplet state was used to determine the hyperfine structure of this previously unobserved molecular state.

Long-Lived Ultracold Molecules with Electric and Magnetic Dipole Moments

NASA Astrophysics Data System (ADS)

Rvachov, Timur M.; Son, Hyungmok; Sommer, Ariel T.; Ebadi, Sepehr; Park, Juliana J.; Zwierlein, Martin W.; Ketterle, Wolfgang; Jamison, Alan O.

2017-10-01

We create fermionic dipolar 23Na 6Li molecules in their triplet ground state from an ultracold mixture of 23Na and 6Li. Using magnetoassociation across a narrow Feshbach resonance followed by a two-photon stimulated Raman adiabatic passage to the triplet ground state, we produce 3 ×1 04 ground state molecules in a spin-polarized state. We observe a lifetime of 4.6 s in an isolated molecular sample, approaching the p -wave universal rate limit. Electron spin resonance spectroscopy of the triplet state was used to determine the hyperfine structure of this previously unobserved molecular state.

The laser versus the lamp: Reactivity of the diphenyl ketyl radical in the ground and excited states

NASA Astrophysics Data System (ADS)

Baumann, H.; Merckel, C.; Timpe, H.-J.; Graness, A.; Kleinschmidt, J.; Gould, I. R.; Turro, N. J.

1984-01-01

The diphenyl ketyl radical which is formed upon photolysis of α-phenyl benzoin is produced in its excited state upon intense pulsed laser irradiation. Using the techniques of time-resolved absorption and emission spectroscopy, reaction rate constants for the ground and excited states of this radical were obtained. For the radical quenchers employed, the excited state reactivity is found to be typically several orders of magnitude greater than that of the ground state. It is concluded that the excited state of diphenyl ketyl radical reacts predominantly by electron transfer processes.

Jahn-Teller distortion in the phosphorescent excited state of three-coordinate Au(I) phosphine complexes.

PubMed

Barakat, Khaldoon A; Cundari, Thomas R; Omary, Mohammad A

2003-11-26

DFT calculations were used to optimize the phosphorescent excited state of three-coordinate [Au(PR3)3]+ complexes. The results indicate that the complexes rearrange from their singlet ground-state trigonal planar geometry to a T-shape in the lowest triplet luminescent excited state. The optimized structure of the exciton contradicts the structure predicted based on the AuP bonding properties of the ground-state HOMO and LUMO. The rearrangement to T-shape is a Jahn-Teller distortion because an electron is taken from the degenerate e' (5dxy, 5dx2-y2) orbital upon photoexcitation of the ground-state D3h complex. The calculated UV absorption and visible emission energies are consistent with the experimental data and explain the large Stokes' shifts while such correlations are not possible in optimized models that constrained the exciton to the ground-state trigonal geometry.

Mississippi Embayment Regional Ground Water Study

EPA Science Inventory

Increased water usage in the southeastern United States in the tri-state area of Tennessee, Mississippi and Arkansas poses a dilemma to ensuring long-term sustainability of the quantity and quality of ground-water resources that underlie the region. Demand for ground water by ag...

The role of ground water in the national water situation: With state summaries based on reports by District Offices of Ground Water Branch

USGS Publications Warehouse

McGuinness, Charles Lee

1963-01-01

This report outlines briefly the principles of water occurrence and describes the water situation in the United States as of 1960-61, with emphasis on the occurrence of ground water and the status of development and accompanying problems. The Nation has been divided into 10 major ground-water regions by H. E. Thomas (1952a). The report summarizes the occurrence and development of ground water in each of Thomas' regions. In a large terminal section it also describes the occurrence and development of water, again with emphasis on ground water, in each of the 50 States and in certain other areas. The main text ends with a discussion of the water situation and prospects of the Nation.

XYZ-SU3 breakings from Laplace sum rules at higher orders

NASA Astrophysics Data System (ADS)

Albuquerque, R.; Narison, S.; Rabetiarivony, D.; Randriamanatrika, G.

2018-06-01

We present new compact integrated expressions of SU3 breaking corrections to QCD spectral functions of heavy-light molecules and four-quark XY Z-like states at lowest order (LO) of perturbative (PT) QCD and up to d = 8 condensates of the Operator Product Expansion (OPE). Including next-to-next-to-leading order (N2LO) PT corrections in the chiral limit and next-to-leading order (NLO) SU3 PT corrections, which we have estimated by assuming the factorization of the four-quark spectral functions, we improve previous LO results for the XY Z-like masses and decay constants from QCD spectral sum rules (QSSR). Systematic errors are estimated from a geometric growth of the higher order PT corrections and from some partially known d = 8 nonperturbative contributions. Our optimal results, based on stability criteria, are summarized in Tables 18-21 while the 0++ and 1++ channels are compared with some existing LO results in Table 22. One can note that, in most channels, the SU3 corrections on the meson masses are tiny: ≤ 10% (respectively ≤ 3%) for the c (respectively b)-quark channel but can be large for the couplings ( ≤ 20%). Within the lowest dimension currents, most of the 0++ and 1++ states are below the physical thresholds while our predictions cannot discriminate a molecule from a four-quark state. A comparison with the masses of some experimental candidates indicates that the 0++ X(4500) might have a large D¯s0∗D s0∗ molecule component while an interpretation of the 0++ candidates as four-quark ground states is not supported by our findings. The 1++ X(4147) and X(4273) are compatible with the D¯s∗D s, D¯s0∗D s1 molecules and/or with the axial-vector Ac four-quark ground state. Our results for the 0‑±, 1‑± and for different beauty states can be tested in the future data. Finally, we revisit our previous estimates1 for the D¯0∗D 0∗ and D¯0∗D 1 and present new results for the D¯1D1.

Quantum entanglement distillation with metamaterials.

PubMed

al Farooqui, Md Abdullah; Breeland, Justin; Aslam, Muhammad I; Sadatgol, Mehdi; Özdemir, Şahin K; Tame, Mark; Yang, Lan; Güney, Durdu Ö

2015-07-13

We propose a scheme for the distillation of partially entangled two-photon Bell and three-photon W states using metamaterials. The distillation of partially entangled Bell states is achieved by using two metamaterials with polarization dependence, one of which is rotated by π/2 around the direction of propagation of the photons. On the other hand, the distillation of three-photon W states is achieved by using one polarization dependent metamaterial and two polarization independent metamaterials. Upon transmission of the photons of the partially entangled states through the metamaterials the entanglement of the states increases and they become distilled. This work opens up new directions in quantum optical state engineering by showing how metamaterials can be used to carry out a quantum information processing task.

Superposing pure quantum states with partial prior information

NASA Astrophysics Data System (ADS)

Dogra, Shruti; Thomas, George; Ghosh, Sibasish; Suter, Dieter

2018-05-01

The principle of superposition is an intriguing feature of quantum mechanics, which is regularly exploited in many different circumstances. A recent work [M. Oszmaniec et al., Phys. Rev. Lett. 116, 110403 (2016), 10.1103/PhysRevLett.116.110403] shows that the fundamentals of quantum mechanics restrict the process of superimposing two unknown pure states, even though it is possible to superimpose two quantum states with partial prior knowledge. The prior knowledge imposes geometrical constraints on the choice of input states. We discuss an experimentally feasible protocol to superimpose multiple pure states of a d -dimensional quantum system and carry out an explicit experimental realization for two single-qubit pure states with partial prior information on a two-qubit NMR quantum information processor.

Electronic, magnetic properties and phase diagrams of system with Fe4N compound: An ab initio calculations and Monte Carlo study

NASA Astrophysics Data System (ADS)

Masrour, R.; Jabar, A.; Hlil, E. K.

2018-05-01

Self-consistent ab initio calculations, based on Density Functional Theory (DFT) approach and using Full potential Linear Augmented Plane Wave (FLAPW) method, are performed to investigate the electronic and magnetic properties of the Fe4N compound. Polarized spin and spin-orbit coupling are included in calculations within the framework of the ferromagnetic state between Fe(I) and Fe(II) in Fe4N compound. We have used the obtained data from abinitio calculations as an input in Monte Carlo simulation to calculate the magnetic properties of this compounds such as the ground state phase diagrams, total and partial magnetization of Fe(I) and Fe(II) as well as the transition temperatures are computed. The variation of magnetization with the crystal field are also studied. The magnetic hysteresis cycle of the same Fe4N compound are determined for different values of temperatures and crystal field values. The two-step hysteresis loop are evidenced, which is typical for Fe4N structure. The ferromagnetic and superparamagnetic phase is observed as well.

Low Energy Nuclear Structure Modeling: Can It Be Improved?

NASA Astrophysics Data System (ADS)

Stone, Jirina R.

Since the discovery of the atomic nucleus in 1911 generations of physicists have devoted enormous effort to understand low energy nuclear structure. Properties of nuclei in their ground state, including mass, binding energy and shape, provide vital input to many areas of sub-atomic physics as well as astrophysics and cosmology. Low energy excited states are equally important for understanding nuclear dynamics. Yet, no consensus exists as to what is the best path to a theory which would not only consistently reproduce a wide variety of experimental data but also have enough predictive power to yield credible predictions in areas where data are still missing. In this contribution some of the main obstacles preventing building such a theory are discussed. These include modification of the free nucleon-nucleon force in the nuclear environment and effects of the sub-nucleon (quark) structure of the nucleon. Selected classes of nuclear models, mean-field, shell and ab-initio models are briefly outlined. Finally, suggestions are made for, at least partial, progress that can be achieved with the quark-meson coupling model, as reported in recent publication [1].

Can one ADM quantize relativistic bosonicstrings and membranes?

NASA Astrophysics Data System (ADS)

Moncrief, Vincent

2006-04-01

The standard methods for quantizing relativistic strings diverge significantly from the Dirac-Wheeler-DeWitt program for quantization of generally covariant systems and one wonders whether the latter could be successfully implemented as an alternative to the former. As a first step in this direction, we consider the possibility of quantizing strings (and also relativistic membranes) via a partially gauge-fixed ADM (Arnowitt, Deser and Misner) formulation of the reduced field equations for these systems. By exploiting some (Euclidean signature) Hamilton-Jacobi techniques that Mike Ryan and I had developed previously for the quantization of Bianchi IX cosmological models, I show how to construct Diff( S 1)-invariant (or Diff(Σ)-invariant in the case of membranes) ground state wave functionals for the cases of co-dimension one strings and membranes embedded in Minkowski spacetime. I also show that the reduced Hamiltonian density operators for these systems weakly commute when applied to physical (i.e. Diff( S 1) or Diff(Σ)-invariant) states. While many open questions remain, these preliminary results seem to encourage further research along the same lines.

Water Resources Data, Pennsylvania, Water Year 1999. Volume 1. Delaware River Basin

USGS Publications Warehouse

Durlin, R.R.; Schaffstall, W.P.

2000-01-01

IntroductionThe Water Resources Division of the U.S. Geological Survey, in cooperation with State, municipal, and Federal agencies, collects a large amount of data pertaining to the water resources of Pennsylvania each water year. These data, accumulated during many water years, constitute a valuable data base for developing an improved understanding of the water resources of the State. To make these data readily available to interested parties outside the Geological Survey, these data are published annually in this report series entitled "Water Resources Data - Pennsylvania, Volumes 1, 2, and 3." Volume 1 contains data for the Delaware River Basin; Volume 2, the Susquehanna and Potomac River Basins; and Volume 3, the Ohio River and St. Lawrence River Basins.This report, Volume 1, contains: (1) discharge records for 74 continuous-record streamflow-gaging stations, 7 partial-record stations, and 13 special study and miscellaneous streamflow sites; (2) elevation and contents records for 14 lakes and reservoirs; (3) water-quality records for 29 gaging stations and 11 ungaged streamsites; (4) water-quality records for 87 special-study stations;(5) water-level records for 55 network observation wells; and (6) water-quality analyses of ground water from 11 ground-water wells. Additional water data collected at various sites not involved in the systematic data-collection program may also be presented.Publications similar to this report are published annually by the Geological Survey for all States. For the purpose of archiving, these official reports have an identification number consisting of the two-letter State abbreviation, the last two digits of the water year, and the volume number. For example, this volume is identified as "U.S. Geological Survey Water-Data Report PA-99-1." These water data reports, beginning with the 1971 water year, are for sale as paper copy or microfiche by the National Technical Information Service, U.S. Department of Commerce, Springfield, VA 22161.The annual series of Water Data Reports for Pennsylvania began with the 1961 water-year report and contained only data relating to quantities of surface water. With the 1964 water year, a companion report (part 2) was introduced that contained only data relating to water quality. Beginning with the 1975 water year the report was changed to its present format of three volumes (by river basin), with each volume containing data on quantities of surface water, quality of surface and ground water, and ground-water levels.Prior to the introduction of this series and for several years concurrent with it, water-resources data for Pennsylvania were published in U.S. Geological Survey Water-Supply Papers. Data on stream discharge and stage, and on lake or reservoir contents and stage, through September 1960, were published annually under the title "Surface-Water Supply of the United States," which was released in numbered parts as determined by natural drainage basins. For the 1961-70 water years, these data were published in two 5-year reports. Data prior to 1961 are included in two reports: "Compilation of Records of Surface Waters of the United States through 1950," and "Compilation of Records of Surface Waters of the United States, October 1950 to September 1960." Data for Pennsylvania are published in Parts 1, 3, and 4. Data on chemical quality, temperature, and suspended sediment for the 1941-70 water years were published annually under the title "Quality of Surface Waters of the United States," and ground-water levels for the 1935-74 water years were published under the title "Ground-Water Levels in the United States." The above mentioned Water-Supply Papers may be consulted in the libraries of the principal cities of the United States and may be purchased from the U.S. Geological Survey, Information Services, Box 25286, Denver, CO 80225.Information for ordering specific reports may be obtained from the Pennsylvania District Office at the address given on the back of the title page or by phoning the Scientific and Technical Products Section, at (717) 730-6940. Information on the availability of unpublished data or statistical analyses may be obtained from the District Information Specialist by telephone at (717) 730-6916 or by FAX at (717) 730-6997.

Water Resources Data, Pennsylvania, Water Year 2001. Volume 3. Ohio and St. Lawrence River Basins

USGS Publications Warehouse

Siwicki, Raymond W.

2002-01-01

IntroductionThe Water Resources Division of the U.S. Geological Survey, in cooperation with State, municipal, and Federal agencies, collects a large amount of data pertaining to the water resources of Pennsylvania each water year. These data, accumulated during many water years, constitute a valuable data base for developing an improved understanding of the water resources of the State. To make these data readily available to interested parties outside the Geological Survey, these data are published annually in this report series entitled "Water Resources Data - Pennsylvania, Volumes 1, 2, and 3." Volume 1 contains data for the Delaware River Basin; Volume 2, the Susquehanna and Potomac River Basins; and Volume 3, the Ohio and St. Lawrence River Basins.This report, Volume 3, contains: (1) discharge records for 59 continuous-record streamflow-gaging stations, 5 partial-record stations, and 12 special study and miscellaneous streamflow sites; (2) elevation and contents records for 11 lakes and reservoirs; (3) water-quality records for 2 streamflow gaging station and 7 ungaged streamsites; (4) water-level records for 15 ground-water network observation wells; and, (5) water-quality analyses at 2 special study ground-water wells. Additional water data collected at various sites not involved in the systematic data-collection program may also be presented.Publications similar to this report are published annually by the Geological Survey for all States. For the purpose of archiving, these official reports have an identification number consisting of the two-letter State abbreviation, the last two digits of the water year, and the volume number. For example, this volume is identified as "U.S. Geological Survey Water-Data Report PA-01-3." These water-data reports, beginning with the 1971 water year, are for sale as paper copy or microfiche by the National Technical Information Service, U.S. Department of Commerce, Springfield, VA 22161.The annual series of Water Data Reports for Pennsylvania began with the 1961 water-year report and contained only data relating to quantities of surface water. With the 1964 water year, a companion report (part 2) was introduced that contained only data relating to water quality. Beginning with the 1975 water year the report was changed to three volumes (by river basin), with each volume containing data on quantities of surface water, quality of surface and ground water, and ground-water levels.Prior to the introduction of this series and for several years concurrent with it, water-resources data for Pennsylvania were published in U.S. Geological Survey Water-Supply Papers. Data on stream discharge and stage, and on lake or reservoir contents and stage, through September 1960, were published annually under the title "Surface-Water Supply of the United States," which was released in numbered parts as determined by natural drainage basins. For the 1961-70 water years, these data were published in two 5-year reports. Data prior to 1961 are included in two reports: "Compilation of Records of Surface Waters of the United States through 1950," and "Compilation of Records of Surface Waters of the United States, October 1950 to September 1960." Data for Pennsylvania are published in Parts 1, 3, and 4. Data on chemical quality, temperature, and suspended sediment for the 1941-70 water years were published annually under the title "Quality of Surface Waters of the United States," and ground-water levels for the 1935-74 water years were published annually under the title "Ground-Water Levels in the United States." The above mentioned Water-Supply Papers may be consulted in the libraries of the principal cities of the United States and may be purchased from the U.S. Geological Survey, Information Services, Box 25286, Denver, CO 80225.Information for ordering specific reports may be obtained from the Pennsylvania District Office at the address on the back of the title page or by phoning the Scientific and Technical Products Section at (717) 730-6940. Information on the availability of unpublished data or statistical analyses may be obtained from the District Information Specialist by telephone at (717) 730-6916 or by FAX at (717) 730-6997.

Water Resources Data, Pennsylvania, Water Year 2001. Volume 1. Delaware River Basin

USGS Publications Warehouse

Durlin, R.R.; Schaffstall, W.P.

2002-01-01

IntroductionThe Water Resources Division of the U.S. Geological Survey, in cooperation with State, municipal, and Federal agencies, collects a large amount of data pertaining to the water resources of Pennsylvania each water year. These data, accumulated during many water years, constitute a valuable data base for developing an improved understanding of the water resources of the State. To make these data readily available to interested parties outside the Geological Survey, these data are published annually in this report series entitled "Water Resources Data - Pennsylvania, Volumes 1, 2, and 3." Volume 1 contains data for the Delaware River Basin; Volume 2, the Susquehanna and Potomac River Basins; and Volume 3, the Ohio River and St. Lawrence River Basins.This report, Volume 1, contains: (1) discharge records for 77 continuous-record streamflow-gaging stations, 7 partial-record stations, and 46 special study and miscellaneous streamflow sites; (2) elevation and contents records for 13 lakes and reservoirs; (3) water-quality records for 28 gaging stations and 11 ungaged streamsites; (4) water-quality records for 27 special-study stations; (5) water-level records for 56 network observation wells; and (6) water-quality analyses of ground water from 111 ground-water wells. Additional water data collected at various sites not involved in the systematic data-collection program may also be presented.Publications similar to this report are published annually by the Geological Survey for all States. For the purpose of archiving, these official reports have an identification number consisting of the two-letter State abbreviation, the last two digits of the water year, and the volume number. For example, this volume is identified as "U.S. Geological Survey Water-Data Report PA-01-1." These water data reports, beginning with the 1971 water year, are for sale as paper copy or microfiche by the National Technical Information Service, U.S. Department of Commerce, Springfield, VA 22161.The annual series of Water Data Reports for Pennsylvania began with the 1961 water-year report and contained only data relating to quantities of surface water. With the 1964 water year, a companion report (part 2) was introduced that contained only data relating to water quality. Beginning with the 1975 water year the report was changed to its present format of three volumes (by river basin), with each volume containing data on quantities of surface water, quality of surface and ground water, and ground-water levels.Prior to the introduction of this series and for several years concurrent with it, water-resources data for Pennsylvania were published in U.S. Geological Survey Water-Supply Papers. Data on stream discharge and stage, and on lake or reservoir contents and stage, through September 1960, were published annually under the title "Surface-Water Supply of the United States," which was released in numbered parts as determined by natural drainage basins. For the 1961-70 water years, these data were published in two 5-year reports. Data prior to 1961 are included in two reports: "Compilation of Records of Surface Waters of the United States through 1950," and "Compilation of Records of Surface Waters of the United States, October 1950 to September 1960." Data for Pennsylvania are published in Parts 1, 3, and 4. Data on chemical quality, temperature, and suspended sediment for the 1941-70 water years were published annually under the title "Quality of Surface Waters of the United States," and ground-water levels for the 1935-74 water years were published under the title "Ground-Water Levels in the United States." The above mentioned Water-Supply Papers may be consulted in the libraries of the principal cities of the United States and may be purchased from the U.S. Geological Survey, Information Services, Box 25286, Denver, CO 80225.Information for ordering specific reports may be obtained from the Pennsylvania District Office at the address given on the back of the title page or by phoning the Scientific and Technical Products Section, at (717) 730-6940. Information on the availability of unpublished data or statistical analyses may be obtained from the District Information Specialist by telephone at (717) 730-6916 or by FAX at (717) 730-6997.

Water resources data, Pennsylvania, water year 2000, Volume 1. Delaware River Basin

USGS Publications Warehouse

Durlin, R.R.; Schaffstall, W.P.

2001-01-01

The Water Resources Division of the U.S. Geological Survey, in cooperation with State, municipal, and Federal agencies, collects a large amount of data pertaining to the water resources of Pennsylvania each water year. These data, accumulated during many water years, constitute a valuable data base for developing an improved understanding of the water resources of the State. To make these data readily available to interested parties outside the Geological Survey, these data are published annually in this report series entitled "Water Resources Data - Pennsylvania, Volumes 1, 2, and 3." Volume 1 contains data for the Delaware River Basin; Volume 2, the Susquehanna and Potomac River Basins; and Volume 3, the Ohio River and St. Lawrence River Basins.This report, Volume 1, contains: (1) discharge records for 76 continuous-record streamflow-gaging stations, 7 partial-record stations, and 13 special study and miscellaneous streamflow sites; (2) elevation and contents records for 14 lakes and reservoirs; (3) water-quality records for 28 gaging stations and 14 ungaged streamsites; (4) water-quality records for 77 special-study stations; (5) water-level records for 53 network observation wells; and (6) water-quality analyses of ground water from 101 ground-water wells. Additional water data collected at various sites not involved in the systematic data-collection program may also be presented.Publications similar to this report are published annually by the Geological Survey for all States. For the purpose of archiving, these official reports have an identification number consisting of the two-letter State abbreviation, the last two digits of the water year, and the volume number. For example, this volume is identified as "U.S. Geological Survey Water-Data Report PA-00-1." These water data reports, beginning with the 1971 water year, are for sale as paper copy or microfiche by the National Technical Information Service, U.S. Department of Commerce, Springfield, VA 22161.The annual series of Water Data Reports for Pennsylvania began with the 1961 water-year report and contained only data relating to quantities of surface water. With the 1964 water year, a companion report (part 2) was introduced that contained only data relating to water quality. Beginningwith the 1975 water year the report was changed to its present format of three volumes (by river basin), with each volume containing data on quantities of surface water, quality of surface and ground water, and ground-water levels.Prior to the introduction of this series and for several years concurrent with it, water-resources data for Pennsylvania were published in U.S. Geological Survey Water-Supply Papers. Data on stream discharge and stage, and on lake or reservoir contents and stage, through September 1960, were published annually under the title "Surface-Water Supply of the United States," which was released in numbered parts as determined by natural drainage basins. For the 1961-70 water years, these data were published in two 5-year reports. Data prior to 1961 are included in two reports: "Compilation of Records of Surface Waters of the United States through 1950," and "Compilation of Records of Surface Waters of the United States, October 1950 to September 1960." Data for Pennsylvania are published in Parts 1, 3, and 4. Data on chemical quality, temperature, and suspended sediment for the 1941-70 water years were published annually under the title "Quality of Surface Waters of the United States," and ground-water levels for the 1935-74 water years were published under the title "Ground-Water Levels in the United States." The above mentioned Water-Supply Papers may be consulted in the libraries of the principal cities of the United States and may be purchased from the U.S. Geological Survey, Information Services, Box 25286, Denver, CO 80225.Information for ordering specific reports may be obtained from the Pennsylvania District Office at the address given on the back of the title page or by phoning the Scientific and Technical Products Section, at (717) 730-6940. Information on the availability of unpublished data or statistical analyses may be obtained from the District Information Specialist by telephone at (717) 730-6916 or by FAX at (717) 730-6997.

Detection and Analysis of Partial Reflections of HF Waves from the Lower Ionosphere

NASA Astrophysics Data System (ADS)

Erdman, A.; Moore, R. C.

2016-12-01

On the afternoon of August 27, 2011, the western half of the High Frequency Active Auroral Research Program's (HAARP's) HF transmitter repeatedly broadcast a low-power (1 kW/Tx), 4.5-MHz, X-mode polarized, 10 microsecond pulse. The HF beam was directed vertically, and the inter-pulse period was 20 milliseconds. HF observations were performed at Oasis (62° 23' 30" N, 145° 9' 03" W) using two crossed 90-foot folded dipoles. Observations clearly indicate the detection of a ground wave and multiple reflections from different sources at F-region altitudes, which is consistent with digisonde measurements at 4.5 MHz. Additional reflections were detected at a virtual altitude of 90-110 km, and we interpret these reflections as partial reflections from the rapid conductivity change at the base of the ionosphere. We compare these observations with the predictions of a new finite-difference time-domain (FDTD) plasma model. The model is a one-dimensional, second-order accurate, cold plasma FDTD model of the ionosphere extending from ground through the lower F-region. The model accounts for a spatially varying plasma frequency, cyclotron frequency, and electron-neutral collision frequency. We discuss the possibility to analyze partial reflections from the base of the ionosphere as a function of frequency to characterize the reflecting plasma.

Alumina Volatility in Water Vapor at Elevated Temperatures: Application to Combustion Environments

NASA Technical Reports Server (NTRS)

Opila, Elizabeth J.; Myers, Dwight L.

2003-01-01

The volatility of alumina in high temperature water vapor was determined by measuring weight loss of sapphire coupons at temperatures between 1250 and 1500 C, water vapor partial pressures between 0.15 and 0.68 atm in oxygen, at one atmosphere total pressure, and a gas velocity of 4.4 centimeters per second. The variation of the volatility with water vapor partial pressure was consistent with Al(OH)3(g) formation. The enthalpy of reaction to form Al(OH)3(g) from alumina and water vapor was found to be 210 plus or minus 20 kJ/mol. Surface rearrangement of ground sapphire surfaces increased with water vapor partial pressure, temperature and volatility rate. Recession rates of alumina due to volatility were determined as a function of water vapor partial pressure and temperature to evaluate limits for use of alumina in long term applications in combustion environments.

Decay studies of a long lived high spin isomer of /sup 210/Bi

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tuggle, D.G.

1976-08-01

A source of approximately 30 ..mu..g of pure (> 90%) /sup 210m/Bi (J..pi.. = 9-) was prepared by irradiating /sup 209/Bi in a nuclear reactor. After chemical separations to remove /sup 210/Po from the irradiated bismuth sample were completed, the /sup 210/Bi was electromagnetically separated from the /sup 209/Bi by a series of two isotope separations to create the source mentioned above. This source was then used to conduct alpha, conversion electron, gamma, gamma-gamma coincidence, and alpha-gamma coincidence spectroscopic studies of the decay of /sup 210m/Bi. The partial half life for the alpha decay of /sup 210m/Bi was measured asmore » 3.0 x 10/sup 6/ yr. A lower limit of 10/sup 13/ years was set for the partial half life for the decay of /sup 210m/Bi to /sup 210/Po. Alpha decay of /sup 210m/Bi to 8 excited states of /sup 206/Tl was observed. A lower limit of 10/sup -4/% was set for the branching ratio of the parity forbidden alpha decay of /sup 210/Bi to the /sup 206/Ti ground state. Theoretical decay rates for the alpha decays of /sup 210m/Bi, /sup 210/Bi, /sup 211/Po, and /sup 211m/Po were calculated using the method developed by Hans Mang. A comparison of the calculated and experimentally measured alpha decay rates of /sup 210m/Bi showed good agreement for the relative alpha decay rates.« less

Structural physical approximation for the realization of the optimal singlet fraction with two measurements

NASA Astrophysics Data System (ADS)

Adhikari, Satyabrata

2018-04-01

Structural physical approximation (SPA) has been exploited to approximate nonphysical operation such as partial transpose. It has already been studied in the context of detection of entanglement and found that if the minimum eigenvalue of SPA to partial transpose is less than 2/9 then the two-qubit state is entangled. We find application of SPA to partial transpose in the estimation of the optimal singlet fraction. We show that the optimal singlet fraction can be expressed in terms of the minimum eigenvalue of SPA to partial transpose. We also show that the optimal singlet fraction can be realized using Hong-Ou-Mandel interferometry with only two detectors. Further we have shown that the generated hybrid entangled state between a qubit and a binary coherent state can be used as a resource state in quantum teleportation.

Effect of single-site mutations on hydrophobic-polar lattice proteins

NASA Astrophysics Data System (ADS)

Shi, Guangjie; Vogel, Thomas; Wüst, Thomas; Li, Ying Wai; Landau, David P.

2014-09-01

We developed a heuristic method for determining the ground-state degeneracy of hydrophobic-polar (HP) lattice proteins, based on Wang-Landau and multicanonical sampling. It is applied during comprehensive studies of single-site mutations in specific HP proteins with different sequences. The effects in which we are interested include structural changes in ground states, changes of ground-state energy, degeneracy, and thermodynamic properties of the system. With respect to mutations, both extremely sensitive and insensitive positions in the HP sequence have been found. That is, ground-state energies and degeneracies, as well as other thermodynamic and structural quantities, may be either largely unaffected or may change significantly due to mutation.

Structure, strain, and control of ground state property in LaTiO3/LaAlO3 superlattice

NASA Astrophysics Data System (ADS)

Lee, Alex Taekyung; Han, Myung Joon

2014-03-01

We examined the ground state property of LaTiO3/LaAlO3 superlattice through density functional band calculations. Total energy calculations, including the structural distortions, U dependence, and the exchange correlation functional dependence, clearly showed that the spin and orbital ground state can be controlled systematically by the epitaxial strain. In the wide range of strain, the ferromagnetic-spin and antiferro-orbital order are stabilized, which is notably different from the previously reported ground state in the titanate systems. By applying +2.8% of tensile strains, we showed that the antiferromagnetic-spin and ferro-orbital ordered phase become stabilized.

Ground state sign-changing solutions for fractional Kirchhoff equations in bounded domains

NASA Astrophysics Data System (ADS)

Luo, Huxiao; Tang, Xianhua; Gao, Zu

2018-03-01

We study the existence of ground state sign-changing solutions for the fractional Kirchhoff problem. Under mild assumptions on the nonlinearity, by using some new analytical skills and the non-Nehari manifold method, we prove that the fractional Kirchhoff problem possesses a ground state sign-changing solution ub. Moreover, we show that the energy of ub is strictly larger than twice that of the ground state solutions of Nehari-type. Finally, we establish the convergence property of ub as the parameter b ↘ 0. Our results generalize some results obtained by Shuai [J. Differ. Equations 259, 1256 (2015)] and Tang and Cheng [J. Differ. Equations 261, 2384 (2016)].

Probing quantum frustrated systems via factorization of the ground state.

PubMed

Giampaolo, Salvatore M; Adesso, Gerardo; Illuminati, Fabrizio

2010-05-21

The existence of definite orders in frustrated quantum systems is related rigorously to the occurrence of fully factorized ground states below a threshold value of the frustration. Ground-state separability thus provides a natural measure of frustration: strongly frustrated systems are those that cannot accommodate for classical-like solutions. The exact form of the factorized ground states and the critical frustration are determined for various classes of nonexactly solvable spin models with different spatial ranges of the interactions. For weak frustration, the existence of disentangling transitions determines the range of applicability of mean-field descriptions in biological and physical problems such as stochastic gene expression and the stability of long-period modulated structures.

Trampoline Resonator Fabrication for Tests of Quantum Mechanics at High Mass

NASA Astrophysics Data System (ADS)

Weaver, Matthew; Pepper, Brian; Sonin, Petro; Eerkens, Hedwig; Buters, Frank; de Man, Sven; Bouwmeester, Dirk

2014-03-01

There has been much interest recently in optomechanical devices that can reach the ground state. Two requirements for achieving ground state cooling are high optical finesse in the cavity and high mechanical quality factor. We present a set of trampoline resonator devices using high stress silicon nitride and superpolishing of mirrors with sufficient finesse (as high as 60,000) and quality factor (as high as 480,000) for ground state cooling in a dilution refrigerator. These devices have a higher mass, between 80 and 100 ng, and lower frequency, between 200 and 500 kHz, than other devices that have been cooled to the ground state, enabling tests of quantum mechanics at a larger mass scale.

Bibliography of publications relating to ground water in Connecticut

USGS Publications Warehouse

Cushman, R.V.

1950-01-01

In 1939, when it became necessary to curtail the work being carried on by the Works Progress Administration, cooperation was arranged between the Federal Ecological Survey and the State Water Commission to continue investigations relative to the over-development of ground-water supplies in the New Haven area. From time to time additional funds have been made available to meet growing demands by the State for data on its ground-water supplied and the present cooperative program between the U.S. Geological Survey and the State Water Commission is a continuation of the original arrangement. It is estimated that about 14 per cont of the State has been covered by recent ground-water surveys and in addition some data are available for another 20 per cent of he State.

Water Resources Data, New York, Water Year 1996; Volume 1. Eastern New York; Excluding Long Island

USGS Publications Warehouse

Butch, G.K.; Dalton, F.N.; Lent, H.G.; Murray, P.M.

1997-01-01

IntroductionWater-resources data for the 1996 water year for New York consist of records of stage, discharge, and water quality of streams; stage, contents, and water quality of lakes and reservoirs; ground-water levels; and precipitation quality. This volume contains records for water discharge at 122 gaging stations; stage only at 7 gaging stations; stage and contents at 4 gaging stations, and 18 other lakes and reservoirs; water quality at 28 gaging stations and 1 precipitation-quality station; and water levels at 3 observation wells. Also included are data for 33 crest-stage partial-record stations. Additional water data were collected at various sites not involved in the systematic data-collection program, and are published as miscellaneous measurements and analyses in this volume. These data together with the data in Volumes 2 and 3 represent that part of the National Water Data System operated by the U.S. Geological Survey in cooperation with State, Municipal, and Federal agencies in New York.Records of discharge and stage of streams, and contents and stage of lakes and reservoirs, were first published in a series of U.S. Geological Survey water-supply papers entitled, “Surface Water Supply of the United States.” Through September 30, 1960, these water-supply papers were in an annual series and then in a 5-year series for 1961-65 and 1966-70. Records of water quality, water temperatures, and suspended sediment were published from 1941 to 1970 in an annual series of water-supply papers entitled “Quality of Surface Waters of the United States.” Records of ground-water levels were published from 1935 to 1974 in a series of water-supply papers entitled “Ground-Water Levels in the United States.” Water-supply papers may be consulted in the libraries of the principal cities and universities in the United States or may be purchased from the U.S. Geological Survey, Branch of Distribution, 604 South Pickett Street, Alexandria, VA 22304.Since the 1961 water year, streamflow data and since the 1964 water year, water-quality data have been released by the Geological Survey in annual reports on a State-boundary basis. These reports provided rapid release of water data in each state shortly after the end of the water year. Through 1970 the data were also released in the water-supply paper series mentioned above.Streamflow and water-quality data beginning with the 1971 water year, and ground-water data beginning with the 1975 water year are published only in reports on a State-boundary basis. Beginning with the 1975 water year, these Survey reports carry an identification number consisting of the two-letter State abbreviation, the last two digits of the water year, and the volume number. For example, this volume is identified as “U.S. Geological Survey Water-Data Report NY-96-1.” Water-data reports are for sale in paper copy or in microfiche by the National Technical Information Service, U.S. Department of Commerce, Springfield, VA 22161.Additional information, including current prices for ordering specific reports, may be obtained from the District Office at the address given on the back of the title page or by telephone (518) 285-5600.

Influence of barrier on partial discharge activity by a conducting particle in liquid nitrogen under AC voltages adopting UHF technique

NASA Astrophysics Data System (ADS)

Sarathi, R.; Giridhar, A. V.; Sethupathi, K.

2011-02-01

The UHF signals are generated due to PD formed by particle movement in liquid nitrogen under AC voltages. The levitation voltage of a particle in liquid nitrogen measured through UHF technique and by conventional PD measurement technique is the same, confirming the sensitivity of UHF technique for identification of PD activity. The frequency content of UHF signal generated due to particle movement in liquid nitrogen, under AC voltages, lies in the range 0.5-1.5 GHz. The characteristics of UHF signal generated due to particle movement between the barrier and high voltage/ground electrode is much similar to the signal generated by particle movement in clean electrode gap. Pseudo resonance phenomena can occur in liquid nitrogen due to particle movement. It is also observed that the partial discharge magnitude, in general, be high when the particle moves between the barrier and high voltage electrode when compared to the barrier and the ground electrode. Percentage of clay in epoxy nanocomposites has not altered the levitation voltage of the particle in the electrode gap. Zero span analysis clearly indicates that pseudo resonance occurs when particle moves (in a short gap) between the barrier and high voltage/ground electrode.

Experimental Insights into Ground-State Selection of Quantum XY Pyrochlores

NASA Astrophysics Data System (ADS)

Hallas, Alannah M.; Gaudet, Jonathan; Gaulin, Bruce D.

2018-03-01

Extensive experimental investigations of the magnetic structures and excitations in the XY pyrochlores have been carried out over the past decade. Three families of XY pyrochlores have emerged: Yb2B2O7, Er2B2O7, and, most recently, [Formula: see text]Co2F7. In each case, the magnetic cation (either Yb, Er, or Co) exhibits XY anisotropy within the local pyrochlore coordinates, a consequence of crystal field effects. Materials in these families display rich phase behavior and are candidates for exotic ground states, such as quantum spin ice, and exotic ground-state selection via order-by-disorder mechanisms. In this review, we present an experimental summary of the ground-state properties of the XY pyrochlores, including evidence that they are strongly influenced by phase competition. We empirically demonstrate the signatures for phase competition in a frustrated magnet: multiple heat capacity anomalies, suppressed TN or TC, sample- and pressure-dependent ground states, and unconventional spin dynamics.

Extremal optimization for Sherrington-Kirkpatrick spin glasses

NASA Astrophysics Data System (ADS)

Boettcher, S.

2005-08-01

Extremal Optimization (EO), a new local search heuristic, is used to approximate ground states of the mean-field spin glass model introduced by Sherrington and Kirkpatrick. The implementation extends the applicability of EO to systems with highly connected variables. Approximate ground states of sufficient accuracy and with statistical significance are obtained for systems with more than N=1000 variables using ±J bonds. The data reproduces the well-known Parisi solution for the average ground state energy of the model to about 0.01%, providing a high degree of confidence in the heuristic. The results support to less than 1% accuracy rational values of ω=2/3 for the finite-size correction exponent, and of ρ=3/4 for the fluctuation exponent of the ground state energies, neither one of which has been obtained analytically yet. The probability density function for ground state energies is highly skewed and identical within numerical error to the one found for Gaussian bonds. But comparison with infinite-range models of finite connectivity shows that the skewness is connectivity-dependent.

Temperature Effect of Hydrogen-Like Impurity on the Ground State Energy of Strong Coupling Polaron in a RbCl Quantum Pseudodot

NASA Astrophysics Data System (ADS)

Xiao, Jing-Lin

2016-11-01

We study the ground state energy and the mean number of LO phonons of the strong-coupling polaron in a RbCl quantum pseudodot (QPD) with hydrogen-like impurity at the center. The variations of the ground state energy and the mean number of LO phonons with the temperature and the strength of the Coulombic impurity potential are obtained by employing the variational method of Pekar type and the quantum statistical theory (VMPTQST). Our numerical results have displayed that [InlineMediaObject not available: see fulltext.] the absolute value of the ground state energy increases (decreases) when the temperature increases at lower (higher) temperature regime, [InlineMediaObject not available: see fulltext.] the mean number of the LO phonons increases with increasing temperature, [InlineMediaObject not available: see fulltext.] the absolute value of ground state energy and the mean number of LO phonons are increasing functions of the strength of the Coulombic impurity potential.

A projection gradient method for computing ground state of spin-2 Bose–Einstein condensates

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Hanquan, E-mail: hanquan.wang@gmail.com; Yunnan Tongchang Scientific Computing and Data Mining Research Center, Kunming, Yunnan Province, 650221

In this paper, a projection gradient method is presented for computing ground state of spin-2 Bose–Einstein condensates (BEC). We first propose the general projection gradient method for solving energy functional minimization problem under multiple constraints, in which the energy functional takes real functions as independent variables. We next extend the method to solve a similar problem, where the energy functional now takes complex functions as independent variables. We finally employ the method into finding the ground state of spin-2 BEC. The key of our method is: by constructing continuous gradient flows (CGFs), the ground state of spin-2 BEC can bemore » computed as the steady state solution of such CGFs. We discretized the CGFs by a conservative finite difference method along with a proper way to deal with the nonlinear terms. We show that the numerical discretization is normalization and magnetization conservative and energy diminishing. Numerical results of the ground state and their energy of spin-2 BEC are reported to demonstrate the effectiveness of the numerical method.« less

Resonant two-photon ionization spectroscopy of jet-cooled UN: determination of the ground state.

PubMed

Matthew, Daniel J; Morse, Michael D

2013-05-14

The optical transitions of supersonically cooled uranium nitride (UN) have been investigated in the range from 19,200 to 23,900 cm(-1) using resonant two-photon ionization spectroscopy. A large number of bands have been observed, of which seven have been rotationally resolved and analyzed. All are found to arise from the same state, which is presumably the ground state of the molecule. From the analysis of the bands, the ground state has Ω = 3.5, with a bond length of 1.7650(12) Å. Comparisons to the known isovalent molecules are made, and the variations in ground state configuration are explained in terms of the configurational reordering that occurs with changes in the nuclear and ligand charges. It is concluded that the UN molecule is best considered as a U(3+)N(3-) species in which the closed shell nitride ligand interacts with a U(3+) ion. The ground state of the molecule derives from a U(3+) ion in its 7s(1)5f 2) atomic configuration.

High-Order Coupled Cluster Method (CCM) Calculations for Quantum Magnets with Valence-Bond Ground States

NASA Astrophysics Data System (ADS)

Farnell, D. J. J.; Richter, J.; Zinke, R.; Bishop, R. F.

2009-04-01

In this article, we prove that exact representations of dimer and plaquette valence-bond ket ground states for quantum Heisenberg antiferromagnets may be formed via the usual coupled cluster method (CCM) from independent-spin product (e.g. Néel) model states. We show that we are able to provide good results for both the ground-state energy and the sublattice magnetization for dimer and plaquette valence-bond phases within the CCM. As a first example, we investigate the spin-half J 1- J 2 model for the linear chain, and we show that we are able to reproduce exactly the dimerized ground (ket) state at J 2/ J 1=0.5. The dimerized phase is stable over a range of values for J 2/ J 1 around 0.5, and results for the ground-state energies are in good agreement with the results of exact diagonalizations of finite-length chains in this regime. We present evidence of symmetry breaking by considering the ket- and bra-state correlation coefficients as a function of J 2/ J 1. A radical change is also observed in the behavior of the CCM sublattice magnetization as we enter the dimerized phase. We then consider the Shastry-Sutherland model and demonstrate that the CCM can span the correct ground states in both the Néel and the dimerized phases. Once again, very good results for the ground-state energies are obtained. We find CCM critical points of the bra-state equations that are in agreement with the known phase transition point for this model. The results for the sublattice magnetization remain near to the "true" value of zero over much of the dimerized regime, although they diverge exactly at the critical point. Finally, we consider a spin-half system with nearest-neighbor bonds for an underlying lattice corresponding to the magnetic material CaV4O9 (CAVO). We show that we are able to provide excellent results for the ground-state energy in each of the plaquette-ordered, Néel-ordered, and dimerized regimes of this model. The exact plaquette and dimer ground states are reproduced by the CCM ket state in their relevant limits. Furthermore, we estimate the range over which the Néel order is stable, and we find the CCM result is in reasonable agreement with the results obtained by other methods. Our new approach has the dual advantages that it is simple to implement and that existing CCM codes for independent-spin product model states may be used from the outset. Furthermore, it also greatly extends the range of applicability to which the CCM may be applied. We believe that the CCM now provides an excellent choice of method for the study of systems with valence-bond quantum ground states.

Hybrid-PIC Modeling of the Transport of Atomic Boron in a Hall Thruster

NASA Technical Reports Server (NTRS)

Smith, Brandon D.; Boyd, Iaian D.; Kamhawi, Hani

2015-01-01

Computational analysis of the transport of boron eroded from the walls of a Hall thruster is performed by implementing sputter yields of hexagonal boron nitride and velocity distribution functions of boron within the hybrid-PIC model HPHall. The model is applied to simulate NASA's HiVHAc Hall thruster at a discharge voltage of 500V and discharge powers of 1-3 kW. The number densities of ground- and 4P-state boron are computed. The density of ground-state boron is shown to be a factor of about 30 less than the plasma density. The density of the excited state is shown to be about three orders of magnitude less than that of the ground state, indicating that electron impact excitation does not significantly affect the density of ground-state boron in the discharge channel or near-field plume of a Hall thruster. Comparing the rates of excitation and ionization suggests that ionization has a greater influence on the density of ground-state boron, but is still negligible. The ground-state boron density is then integrated and compared to cavity ring-down spectroscopy (CRDS) measurements for each operating point. The simulation results show good agreement with the measurements for all operating points and provide evidence in support of CRDS as a tool for measuring Hall thruster erosion in situ.

Ground states of baryoleptonic Q-balls in supersymmetric models

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shoemaker, Ian M.; Kusenko, Alexander

2008-10-01

In supersymmetric generalizations of the standard model, all stable Q-balls are associated with some flat directions. We show that, if the flat direction has both the baryon number and the lepton number, the scalar field inside the Q-ball can deviate slightly from the flat direction in the ground state. We identify the true ground states of such nontopological solitons, including the electrically neutral and electrically charged Q-balls.

The nu sub 2 band CHD3; ground state parameters for CHD3 from combination differences

NASA Technical Reports Server (NTRS)

Jennings, D. E.; Blass, W. E.

1974-01-01

The nu sub 2 fundamental band of CHD3, centered near 2143/cm, was recorded at a resolution of 0.015-0.25/cm. Analysis of ground state combination differences yielded well-determined values for the ground state molecular parameters for CHD3. These parameters were used in the determination of the alpha and beta molecular parameters for nu sub 2.

Retrieving the ground state of spin glasses using thermal noise: Performance of quantum annealing at finite temperatures.

PubMed

Nishimura, Kohji; Nishimori, Hidetoshi; Ochoa, Andrew J; Katzgraber, Helmut G

2016-09-01

We study the problem to infer the ground state of a spin-glass Hamiltonian using data from another Hamiltonian with interactions disturbed by noise from the original Hamiltonian, motivated by the ground-state inference in quantum annealing on a noisy device. It is shown that the average Hamming distance between the inferred spin configuration and the true ground state is minimized when the temperature of the noisy system is kept at a finite value, and not at zero temperature. We present a spin-glass generalization of a well-established result that the ground state of a purely ferromagnetic Hamiltonian is best inferred at a finite temperature in the sense of smallest Hamming distance when the original ferromagnetic interactions are disturbed by noise. We use the numerical transfer-matrix method to establish the existence of an optimal finite temperature in one- and two-dimensional systems. Our numerical results are supported by mean-field calculations, which give an explicit expression of the optimal temperature to infer the spin-glass ground state as a function of variances of the distributions of the original interactions and the noise. The mean-field prediction is in qualitative agreement with numerical data. Implications on postprocessing of quantum annealing on a noisy device are discussed.

Ground-based research of crystal growth of II-VI compound semiconductors by physical vapor transport

NASA Technical Reports Server (NTRS)

Volz, M. P.; Gillies, D. C.; Szofran, F. R.; Lehoczky, S. L.; Su, Ching-Hua; Sha, Yi-Gao; Zhou, W.; Dudley, M.; Liu, Hao-Chieh; Brebrick, R. F.;

Approximation solution of Schrodinger equation for Q-deformed Rosen-Morse using supersymmetry quantum mechanics (SUSY QM)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Alemgadmi, Khaled I. K., E-mail: azozkied@yahoo.com; Suparmi; Cari

2015-09-30

The approximate analytical solution of Schrodinger equation for Q-Deformed Rosen-Morse potential was investigated using Supersymmetry Quantum Mechanics (SUSY QM) method. The approximate bound state energy is given in the closed form and the corresponding approximate wave function for arbitrary l-state given for ground state wave function. The first excited state obtained using upper operator and ground state wave function. The special case is given for the ground state in various number of q. The existence of Rosen-Morse potential reduce energy spectra of system. The larger value of q, the smaller energy spectra of system.

Variation in migratory behavior influences regional genetic diversity and structure among American kestrel populations (Falco sparverius) in North America

USGS Publications Warehouse

Miller, Mark P.; Mullins, Thomas D.; Parrish, John G.; Walters, Jeffrey R.; Haig, Susan M.

2012-01-01

Birds employ numerous strategies to cope with seasonal fluctuations in high-quality habitat availability. Long distance migration is a common tactic; however, partial migration is especially common among broadly distributed species. Under partial migration systems, a portion of a species migrates, whereas the remainder inhabits breeding grounds year round. In this study, we identified effects of migratory behavior variation on genetic structure and diversity of American Kestrels (Falco sparverius), a widespread partial migrant in North America. American Kestrels generally migrate; however, a resident group inhabits the southeastern United States year round. The southeastern group is designated as a separate subspecies (F. s. paulus) from the migratory group (F. s. sparverius). Using mitochondrial DNA and microsatellites from 183 and 211 individuals, respectively, we illustrate that genetic structure is stronger among nonmigratory populations, with differentiation measures ranging from 0.060 to 0.189 depending on genetic marker and analysis approach. In contrast, measures from western North American populations ranged from 0 to 0.032. These findings suggest that seasonal migratory behavior is also associated with natal and breeding dispersal tendencies. We likewise detected significantly lower genetic diversity within nonmigratory populations, reflecting the greater influence of genetic drift in small populations. We identified the signal of population expansion among nonmigratory populations, consistent with the recent establishment of higher latitude breeding locations following Pleistocene glacial retreat. Differentiation of F. s. paulus and F. s. sparverius reflected subtle differences in allele frequencies. Because migratory behavior can evolve quickly, our analyses suggest recent origins of migratory American Kestrel populations in North America.

Partial covariance based functional connectivity computation using Ledoit-Wolf covariance regularization.

PubMed

Brier, Matthew R; Mitra, Anish; McCarthy, John E; Ances, Beau M; Snyder, Abraham Z

2015-11-01

Functional connectivity refers to shared signals among brain regions and is typically assessed in a task free state. Functional connectivity commonly is quantified between signal pairs using Pearson correlation. However, resting-state fMRI is a multivariate process exhibiting a complicated covariance structure. Partial covariance assesses the unique variance shared between two brain regions excluding any widely shared variance, hence is appropriate for the analysis of multivariate fMRI datasets. However, calculation of partial covariance requires inversion of the covariance matrix, which, in most functional connectivity studies, is not invertible owing to rank deficiency. Here we apply Ledoit-Wolf shrinkage (L2 regularization) to invert the high dimensional BOLD covariance matrix. We investigate the network organization and brain-state dependence of partial covariance-based functional connectivity. Although RSNs are conventionally defined in terms of shared variance, removal of widely shared variance, surprisingly, improved the separation of RSNs in a spring embedded graphical model. This result suggests that pair-wise unique shared variance plays a heretofore unrecognized role in RSN covariance organization. In addition, application of partial correlation to fMRI data acquired in the eyes open vs. eyes closed states revealed focal changes in uniquely shared variance between the thalamus and visual cortices. This result suggests that partial correlation of resting state BOLD time series reflect functional processes in addition to structural connectivity. Copyright © 2015 Elsevier Inc. All rights reserved.

Partial covariance based functional connectivity computation using Ledoit-Wolf covariance regularization

PubMed Central

Brier, Matthew R.; Mitra, Anish; McCarthy, John E.; Ances, Beau M.; Snyder, Abraham Z.

2015-01-01

Functional connectivity refers to shared signals among brain regions and is typically assessed in a task free state. Functional connectivity commonly is quantified between signal pairs using Pearson correlation. However, resting-state fMRI is a multivariate process exhibiting a complicated covariance structure. Partial covariance assesses the unique variance shared between two brain regions excluding any widely shared variance, hence is appropriate for the analysis of multivariate fMRI datasets. However, calculation of partial covariance requires inversion of the covariance matrix, which, in most functional connectivity studies, is not invertible owing to rank deficiency. Here we apply Ledoit-Wolf shrinkage (L2 regularization) to invert the high dimensional BOLD covariance matrix. We investigate the network organization and brain-state dependence of partial covariance-based functional connectivity. Although RSNs are conventionally defined in terms of shared variance, removal of widely shared variance, surprisingly, improved the separation of RSNs in a spring embedded graphical model. This result suggests that pair-wise unique shared variance plays a heretofore unrecognized role in RSN covariance organization. In addition, application of partial correlation to fMRI data acquired in the eyes open vs. eyes closed states revealed focal changes in uniquely shared variance between the thalamus and visual cortices. This result suggests that partial correlation of resting state BOLD time series reflect functional processes in addition to structural connectivity. PMID:26208872

Phenology research for natural resource management in the United States.

PubMed

Enquist, Carolyn A F; Kellermann, Jherime L; Gerst, Katharine L; Miller-Rushing, Abraham J

2014-05-01

Natural resource professionals in the United States recognize that climate-induced changes in phenology can substantially affect resource management. This is reflected in national climate change response plans recently released by major resource agencies. However, managers on-the-ground are often unclear about how to use phenological information to inform their management practices. Until recently, this was at least partially due to the lack of broad-based, standardized phenology data collection across taxa and geographic regions. Such efforts are now underway, albeit in very early stages. Nonetheless, a major hurdle still exists: phenology-linked climate change research has focused more on describing broad ecological changes rather than making direct connections to local to regional management concerns. To help researchers better design relevant research for use in conservation and management decision-making processes, we describe phenology-related research topics that facilitate "actionable" science. Examples include research on evolution and phenotypic plasticity related to vulnerability, the demographic consequences of trophic mismatch, the role of invasive species, and building robust ecological forecast models. Such efforts will increase phenology literacy among on-the-ground resource managers and provide information relevant for short- and long-term decision-making, particularly as related to climate response planning and implementing climate-informed monitoring in the context of adaptive management. In sum, we argue that phenological information is a crucial component of the resource management toolbox that facilitates identification and evaluation of strategies that will reduce the vulnerability of natural systems to climate change. Management-savvy researchers can play an important role in reaching this goal.

First-principles theory of cation- and intercalation-ordering in Li_xCoO_2

NASA Astrophysics Data System (ADS)

Wolverton, C.; Zunger, Alex

1998-03-01

Using a combination of first-principles total energies, a cluster expansion technique, and Monte Carlo simulations, we present a first-principles theory which can predict both cation- and intercalation-ordering patterns at both zero and finite temperatures, and can provide first-principles predictions of battery voltages of Li_xCoO_2/Li cells. The classes of ordering problems that we study are the following: (i) The LiMO2 oxides (M=3d metal) form a series of structures based on an octahedrally-coordinated network with anions (O) on one fcc sublattice and cations (Li and M) on the other, leading to Li/Co ordering in LiCoO2 (x=1). We find the ground state is the CuPt or (111)-layered cation arrangment, in agreement with the observed structure. (ii) In battery applications, Li is (de)intercalated from the compound, creating a vacancy (denoted Box) that can be positioned in different lattice locations; Thus, Box/Co ordering in BoxCoO2 (x=0) is also of interest. We find the ground state for BoxCoO2 is also a (111)-layered structure, although a different stacking sequence (AAA) of close-packed layers is preferred. (iii) The vacancies left behind by Li extraction can form ordered vacancy compounds in partially de-lithiated Li_xCoO_2, leading to a Box/Li ordering problem (0<=x<=1). Our calculations agree with the observed voltage profiles in these systems, and predict the existence of new intercalation-ordered compounds. Supported by BES/OER/DMS under contract DE-AC36-83CH10093.

Photoionization of S3+ using the Breit-Pauli R-matrix method

NASA Astrophysics Data System (ADS)

Stancalie, V.

2018-01-01

Sulphur is one of the most abundant chemical elements in the universe and a large number of lines have been observed in the spectra of astrophysical object. The S IV and SV ions considered in this work have received much interest in the last decade. The main objective of the present work is to report on photoionization cross-sections of S IV using the Breit-Pauli R-matrix (BPRM) method. We have carried out extensive non-relativistic and relativistic calculations of the photoionization cross sections to focus on relativistic effects. The reliability of the atomic data presented here has been carefully tested. We have exploited the BPRM code to describe the atomic wavefunctions and generate the energy levels for the SV 81 fine-structure bound target states and the corresponding A-values for transitions between these levels. The partial and total cross sections for the photoionization of the Al-like S3+ ground and excited states are determined for photon energy ranging from the S4+ 3s2 threshold up to the S4+ 4s threshold. We present statistically weighted, level resolved ground photoionization cross sections for the S IV ion. Both resonance positions and the oscillator strengths are presented. Extensive comparison of the present calculated values with those obtained from direct theoretical scattering calculation is also presented. To the best of our knowledge, the work reported herein describes for the first time a detailed relativistic photoionization calculation for this system, and the results are relevant to the laboratory and astrophysical plasmas.

77 FR 64737 - Partial Approval and Partial Disapproval of Air Quality State Implementation Plans; Nevada...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-10-23

... standard was set at 15 micrograms per cubic meter ([mu]g/m\\3\\), based on the 3-year average of annual... 2.5 standard was set at 65 [mu]g/m\\3\\, based on the 3- year average of the 98th percentile of 24... partially approve the submittal based on EPA's independent evaluation of Nevada's impact on receptor states...

Electronic states and potential energy curves of molybdenum carbide and its ions

NASA Astrophysics Data System (ADS)

Denis, Pablo A.; Balasubramanian, K.

2006-07-01

The potential energy curves and spectroscopic constants of the ground and 29 low-lying excited states of MoC with different spin and spatial symmetries within 48000cm-1 have been investigated. We have used the complete active space multiconfiguration self-consistent field methodology, followed by multireference configuration interaction (MRCI) methods. Relativistic effects were considered with the aid of relativistic effective core potentials in conjunction with these methods. The results are in agreement with previous studies that determined the ground state as XΣ-3. At the MRCISD +Q level, the transition energies to the 1Δ3 and 4Δ1 states are 3430 and 8048cm-1, respectively, in fair agreement with the results obtained by DaBell et al. [J. Chem. Phy. 114, 2938 (2001)], namely, 4003 and 7834cm-1, respectively. The three band systems located at 18 611, 20 700, and 22520cm-1 observed by Brugh et al. [J. Chem. Phy. 109, 7851 (1998)] were attributed to the excited 11Σ-3, 14Π3, and 15Π1 states respectively. At the MRCISD level, these states are 17 560, 20 836, and 20952cm-1 above the ground state respectively. We have also identified a Π3 state lying 14309cm-1 above the ground state. The ground states of the molecular ions are predicted to be Σ-4 and Δ2 for MoC- and MoC+, respectively.

Transfer Function Bounds for Partial-unit-memory Convolutional Codes Based on Reduced State Diagram

NASA Technical Reports Server (NTRS)

Lee, P. J.

1984-01-01

The performance of a coding system consisting of a convolutional encoder and a Viterbi decoder is analytically found by the well-known transfer function bounding technique. For the partial-unit-memory byte-oriented convolutional encoder with m sub 0 binary memory cells and (k sub 0 m sub 0) inputs, a state diagram of 2(K) (sub 0) was for the transfer function bound. A reduced state diagram of (2 (m sub 0) +1) is used for easy evaluation of transfer function bounds for partial-unit-memory codes.

Implementation of rigorous renormalization group method for ground space and low-energy states of local Hamiltonians

NASA Astrophysics Data System (ADS)

Roberts, Brenden; Vidick, Thomas; Motrunich, Olexei I.

2017-12-01

The success of polynomial-time tensor network methods for computing ground states of certain quantum local Hamiltonians has recently been given a sound theoretical basis by Arad et al. [Math. Phys. 356, 65 (2017), 10.1007/s00220-017-2973-z]. The convergence proof, however, relies on "rigorous renormalization group" (RRG) techniques which differ fundamentally from existing algorithms. We introduce a practical adaptation of the RRG procedure which, while no longer theoretically guaranteed to converge, finds matrix product state ansatz approximations to the ground spaces and low-lying excited spectra of local Hamiltonians in realistic situations. In contrast to other schemes, RRG does not utilize variational methods on tensor networks. Rather, it operates on subsets of the system Hilbert space by constructing approximations to the global ground space in a treelike manner. We evaluate the algorithm numerically, finding similar performance to density matrix renormalization group (DMRG) in the case of a gapped nondegenerate Hamiltonian. Even in challenging situations of criticality, large ground-state degeneracy, or long-range entanglement, RRG remains able to identify candidate states having large overlap with ground and low-energy eigenstates, outperforming DMRG in some cases.

Atomic Data on Inelastic Processes in Calcium–Hydrogen Collisions

NASA Astrophysics Data System (ADS)

Belyaev, A. K.; Voronov, Y. V.; Yakovleva, S. A.; Mitrushchenkov, A.; Guitou, M.; Feautrier, N.

2017-12-01

Inelastic cross sections and rate coefficients in Ca + H and Ca+ + H‑ collisions for all transitions between the 17 lowest covalent states plus one ionic molecular state are calculated based on the most recent ab initio adiabatic potentials for the 11 lowest molecular states, as well as on the model asymptotic potentials for higher-lying states, including the ground ionic molecular state. Nuclear dynamics is treated by the probability-current method and the multichannel formulas for the collision energy range 0.01–100 eV. The rates are computed for mutual neutralization, ion-pair formation, and (de-)excitation processes for the temperature range T = 1000–10,000 K. The calculations single out the partial processes with large and moderate rate coefficients. The largest rates correspond to the mutual neutralization into the {Ca}(4s5s{}3S), {Ca}(4s5p{}3P^\\circ ), {Ca}(4s5s{}1S), and {Ca}(4s5p{}{1}P^\\circ ) final states; at T = 6000 K the largest value is 5.50 × 10‑8 cm3 s‑1 for {Ca}(4s5s{}3S). Among the (de-)excitation processes, the largest rate coefficient corresponds to the {Ca}(4s5s{}1S)\\to {Ca}(4s5s{}3S) transition; at T = 6000 K, the largest rate has the value of 8.46 × 10‑9 cm3 s‑1.

Ab initio study of dynamical E × e Jahn-Teller and spin-orbit coupling effects in the transition-metal trifluorides TiF3, CrF3, and NiF3

NASA Astrophysics Data System (ADS)

Mondal, Padmabati; Opalka, Daniel; Poluyanov, Leonid V.; Domcke, Wolfgang

2012-02-01

Multiconfiguration ab initio methods have been employed to study the effects of Jahn-Teller (JT) and spin-orbit (SO) coupling in the transition-metal trifluorides TiF3, CrF3, and NiF3, which possess spatially doubly degenerate excited states (ME) of even spin multiplicities (M = 2 or 4). The ground states of TiF3, CrF3, and NiF3 are nondegenerate and exhibit minima of D3h symmetry. Potential-energy surfaces of spatially degenerate excited states have been calculated using the state-averaged complete-active-space self-consistent-field method. SO coupling is described by the matrix elements of the Breit-Pauli operator. Linear and higher order JT coupling constants for the JT-active bending and stretching modes as well as SO-coupling constants have been determined. Vibronic spectra of JT-active excited electronic states have been calculated, using JT Hamiltonians for trigonal systems with inclusion of SO coupling. The effect of higher order (up to sixth order) JT couplings on the vibronic spectra has been investigated for selected electronic states and vibrational modes with particularly strong JT couplings. While the weak SO couplings in TiF3 and CrF3 are almost completely quenched by the strong JT couplings, the stronger SO coupling in NiF3 is only partially quenched by JT coupling.

Interatomic potentials for Cd, Zn, and Hg from absorption spectra

NASA Astrophysics Data System (ADS)

Su, Ching-Hua; Liao, Pok-Kai; Huang, Yu; Liou, Shian-Shyang; Brebrick, R. F.

1984-07-01

The absorption coefficient has been measured over a 65 nm range in the red wing of the 213.8 nm line for Zn vapor at 1000 °C. It has also been measured in the blue wing and over a 60 nm range in the red wing of the 228.7 nm line for Cd vapor at five temperatures between 642 and 955 °C and over a 75 nm range in the red wing of the 253.7 nm line for Hg vapor at five temperatures between 460 and 860 °C. These data are analyzed in terms of the statistical theory of broadening. Oscillator strengths of 1.42±0.01 and 1.61±0.06 are obtained for, respectively, the Cd line and the Zn line. Pair potentials for both the ground and lowest excited state are also obtained in all three cases. For Cd this is done assuming no functional form and then assuming Lennard-Jones potentials. Both methods agree and give a ground state minimum of -47.5 meV at 0.482 nm separation and an excited state minimum of -1.06 eV at 0.410 nm. A functional form is required for the less extensive Zn data and the Lennard-Jones form leads to a range of possibilities including ground and excited state minima of -56 meV at 0.400 nm and -1.30 eV at 0.330 nm, respectively, which are in fair agreement with the theoretical calculations. For Hg the experiments indicate a single excited state and a ground state with a minimum of -55 meV. Assuming no functional form for the pair potentials, taking the excited state as doubly degenerate, and assuming the transition probability from the ground to excited state is one-sixth of the free atom value gives points along the ground and excited state potentials that join smoothly with other experimental results and agree well with the calculation of Baylis for the ground state.

Experimental entanglement distillation and 'hidden' non-locality.

PubMed

Kwiat, P G; Barraza-Lopez, S; Stefanov, A; Gisin, N

2001-02-22

Entangled states are central to quantum information processing, including quantum teleportation, efficient quantum computation and quantum cryptography. In general, these applications work best with pure, maximally entangled quantum states. However, owing to dissipation and decoherence, practically available states are likely to be non-maximally entangled, partially mixed (that is, not pure), or both. To counter this problem, various schemes of entanglement distillation, state purification and concentration have been proposed. Here we demonstrate experimentally the distillation of maximally entangled states from non-maximally entangled inputs. Using partial polarizers, we perform a filtering process to maximize the entanglement of pure polarization-entangled photon pairs generated by spontaneous parametric down-conversion. We have also applied our methods to initial states that are partially mixed. After filtering, the distilled states demonstrate certain non-local correlations, as evidenced by their violation of a form of Bell's inequality. Because the initial states do not have this property, they can be said to possess 'hidden' non-locality.

GLC_Exec v. 1.2.1

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kilgore, Roger Martin; Soloboda, Alexander Joseph

Launching a rocket involves a controlled transition of the rocket subsystems from a quiescent state to the launch state (i.e., lift-off). In order to launch safely, with confidence that the rocket will successfully complete its mission, the state-of-health for all rocket subsystems and critical ground support equipment must be closely monitored throughout the launch process. This is accomplished by the ground support engineers using mission-specific ground support equipment. A subset of the GSE, the Remote Electrical Ground Interface System (REGIS), is located nearest the rocket to which it's connected via the Umbilical, a wiring harness providing power, sensor, and controlmore » lines. The REGIS also connects via Ethernet to the Ground Launch Computer (GLC).« less

On the low-lying states of TiC

NASA Technical Reports Server (NTRS)

Bauschlicher, C. W., Jr.; Siegbahn, P. E. M.

1984-01-01

The ground and low-lying excited states of TiC are investigated using a CASSCF-externally contracted CI approach. The calculations yield a 3Sigma(+) ground state, but the 1Sigma(+) state is only 780/cm higher and cannot be ruled out. The low-lying states have some triple bond character. The nature of the bonding and origin of the states are discussed.

STATE WATER RESOURCES RESEARCH INSTITUTE PROGRAM: GROUND WATER RESEARCH.

USGS Publications Warehouse

Burton, James S.; ,

1985-01-01

This paper updates a review of the accomplishments of the State Water Resources Research Program in ground water contamination research. The aim is to assess the progress made towards understanding the mechanisms of ground water contamination and based on this understanding, to suggest procedures for the prevention and control of ground water contamination. The following research areas are covered: (1) mechanisms of organic contaminant transport in the subsurface environment; (2) bacterial and viral contamination of ground water from landfills and septic tank systems; (3) fate and persistence of pesticides in the subsurface; (4) leachability and transport of ground water pollutants from coal production and utilization; and (5) pollution of ground water from mineral mining activities.

Stratigraphic test well, Nantucket Island, Massachusetts

USGS Publications Warehouse

Folger, David W.; Hathaway, J.C.; Christopher, R.A.; Valentine, P.C.; Poag, C.W.

1978-01-01

The U.S. Geological Survey, in cooperation with the Massachusetts Water Resources Commission and the Nantucket Conservation Foundation, continuously cored 514 m of sediment and volcanic rock in a stratigraphic and water-quality test near the geographic center of Nantucket Island. Stratified sediments were divided texturally into three zones: the upper zone (0-128 m) contains mostly coarse sand and gravel; the middle zone (128-349 m) contains mostly silty clay and a few beds of sand and silt; and the lower zone (349-457 m) contains soft, unconsolidated, clayey sand. Below the lower zone, a saprolite, composed mostly of clay, grades abruptly downward at 470 m into partially altered basalt that extends to the bottom of the hole at 514 m. Calculations based on the Ghyben-Herzberg principle predicted a zone of freshwater 120-150 m thick. This principle is the theory of hydrostatic equilibrium between freshwater and more dense seawater in a coastal aquifer; it states that for each meter of ground-water elevation above sea level, the freshwater lens will depress the saltwater interface about 40 m below sea level. Freshwater or low-salinity brackish water was found in sediments far below the depth predicted by the Ghyben-Herzberg principle. These interstitial waters are probably relict ground water emplaced during times of low sea level during the Pleistocene. (Woodard-USGS)

Annual summary of ground-water conditions in Arizona, spring 1975 to spring 1976

USGS Publications Warehouse

Babcock, H.M.

1977-01-01

Two small-scale maps of Arizona show (1) pumpage of ground water by areas and (2) the status of the ground-water inventory in the State. A larger map of the State at a scale of 1:500,000 shows potential well production, depth to water in selected wells in spring 1976, and change in water level in selected wells from 1971 to 1976. The brief text that accompanies the maps summarizes the current ground-water conditions in the State. The withdrawal of ground water in Arizona was about 5.6 million acre-feet in 1975, of which about 4.7 million acre-feet was used for the irrigation of crops. The Salt River Valley and the lower Santa Cruz basin are the largest agricultural areas in the State. For 1971-75, ground-water withdrawal in the two areas was about 8.3 and 4.7 million acre-feet, respectively, and, in general, water levels are declining. Other areas in which ground-water withdrawals have caused large water-level declines are the Willcox, San Simon, upper Santa Cruz, Avra Valley, Gila Bend, Harquahala Plains, and McMullen Valley areas. (Woodard-USGS)

Mobility of icy sand packs, with application to Martian permafrost

USGS Publications Warehouse

Durham, W.B.; Pathare, A.V.; Stern, L.A.; Lenferink, H.J.

2009-01-01

[1] The physical state of water on Mars has fundamental ramifications for both climatology and astrobiology. The widespread presence of "softened" Martian landforms (such as impact craters) can be attributed to viscous creep of subsurface ground ice. We present laboratory experiments designed to determine the minimum amount of ice necessary to mobilize topography within Martian permafrost. Our results show that the jammed-to-mobile transition of icy sand packs neither occurs at fixed ice content nor is dependent on temperature or stress, but instead correlates strongly with the maximum dry packing density of the sand component. Viscosity also changes rapidly near the mobility transition. The results suggest a potentially lower minimum volatile inventory for the impact-pulverized megaregolith of Mars. Furthermore, the long-term preservation of partially relaxed craters implies that the ice content of Martian permafrost has remained close to that at the mobility transition throughout Martian history. Copyright 2009 by the American Geophysical Union.

Quantum impurity models for magnetic adsorbates on superconductor surfaces

NASA Astrophysics Data System (ADS)

Žitko, Rok

2018-05-01

Magnetic atoms adsorbed on surfaces have a quenched orbital moment while their ground-state spin multiplet is partially split as a consequence of the spin-orbit coupling which, even if intrinsically weak, has a large effect due to the abrupt change of the potential at the surface. Such metal adsorbates should be modelled using quantum impurity models that include the relevant internal degrees of freedom and the interaction terms, in particular the magnetic anisotropy and the Kondo exchange coupling. When adsorbed on superconducting surfaces, these impurities have complex spectra of sub-gap excitations due to magnetic anisotropy splitting and Kondo screening. Both anisotropy splitting and Zeeman splitting due to the external magnetic field are significantly renormalized by the coupling to the substrate electrons. In this work I discuss the quantum-to-classical crossover and the applicability of classical static-local-spin picture for discussing magnetic nanostructures on superconductors.

Redshift of the light emission from highly strained In0.3Ga0.7As/GaAs quantum wells by dipole δ doping

NASA Astrophysics Data System (ADS)

Fu, Y.; Wang, S.-M.; Wang, X.-D.; Larsson, A.

2005-08-01

We have studied theoretically the energy band structures and optical properties of highly strained dipole δ-doped In0.3Ga0.7As/GaAs single quantum wells. Including dopant diffusion effect, strain in the quantum well, spin-orbital interactions, and many-body effects, the self-consistent calculations of the eight-band k •p model and the Poisson equation show that the dipole δ doping induces an electric field across the In0.3Ga0.7As quantum well by the Stark effect so that both the interband transition energy and the wave-function overlap between the ground-state electrons and holes are reduced. Applying an external bias across the quantum well partially cancels the built-in electric field and reduces the wavelength redshift. The calculated material gain peak is close to the experimental lasing wavelength.

Water Resources Data--Kansas, Water Year 2003

USGS Publications Warehouse

Putnam, J.E.; Schneider, D.R.

2004-01-01

Water-resources data for the 2003 water year for Kansas consist of records of stage, discharge, and water quality of streams; elevation and contents of lakes and reservoirs; and water levels of ground-water wells. This report contains records for water discharge at 148 complete-record gaging stations; elevation and contents at 17 lakes and reservoirs; water-quality records at 2 precipitation stations, water-level data at 12 observation wells; and records of specific conductance, pH, water temperature, dissolved oxygen, and turbidity at 11 gaging stations and 2 lakes with water-quality monitors. Also included are discharge data for 27 high-flow partial-record stations, miscellaneous onsite water-quality data collected at 138 stations, and suspended-sediment concentration for 11 stations. These data represent that part of the National Water Information System collected by the U.S. Geological Survey in cooperation with local, State, and Federal agencies in Kansas.

Dune advance into a coastal forest, equatorial Brazil: A subsurface perspective

NASA Astrophysics Data System (ADS)

Buynevich, Ilya V.; Filho, Pedro Walfir M. Souza; Asp, Nils E.

2010-06-01

A large active parabolic dune along the coast of Pará State, northern Brazil, was analyzed using aerial photography and imaged with high-resolution ground-penetrating radar (GPR) to map the subsurface facies architecture and point-source anomalies. Most high-amplitude (8-10 dB) subsurface anomalies are correlated with partially buried mangrove trees along the leading edge (slipface) of the advancing dune. Profiles along a 200-m long basal stoss side of the dune reveal 66 targets, most of which lie below the water table and are thus inaccessible by other methods. Signal amplitudes of point-source anomalies are substantially higher than those associated with the reflections from continuous subsurface features (water table, sedimentary layers). When complemented with exposures and excavations, GPR provides the best means of rapid continuous imaging of the geological record of complex interactions between vegetation and aeolian deposition.

Theory of ground state factorization in quantum cooperative systems.

PubMed

Giampaolo, Salvatore M; Adesso, Gerardo; Illuminati, Fabrizio

2008-05-16

We introduce a general analytic approach to the study of factorization points and factorized ground states in quantum cooperative systems. The method allows us to determine rigorously the existence, location, and exact form of separable ground states in a large variety of, generally nonexactly solvable, spin models belonging to different universality classes. The theory applies to translationally invariant systems, irrespective of spatial dimensionality, and for spin-spin interactions of arbitrary range.

Lower bounds to energies for cusped-gaussian wavefunctions. [hydrogen atom ground state

NASA Technical Reports Server (NTRS)

Eaves, J. O.; Walsh, B. C.; Steiner, E.

1974-01-01

Calculations for the ground states of H, He, and Be, conducted by Steiner and Sykes (1972), show that the inclusion of a very small number of cusp functions can lead to a substantial enhancement of the quality of the Gaussian basis used in molecular wavefunction computations. The properties of the cusped-Gaussian basis are investigated by a calculation of lower bounds concerning the ground state energy of the hydrogen atom.

Ground-water data collected in the Missouri River Basin units in Kansas during 1954

USGS Publications Warehouse

Mason, B.J.; Loye, Linda

1955-01-01

Ground water studies in the Missouri River basin were begun by the United States Geological Survey during the fall of 1945 as a part of a program for the development of the resources of the basin by the United States Bureau of  Reclamation and other federal agencies. The studies of ground-water resources in the part of Kansas that lies within the Missouri River basin have been coordinated with the cooperative program of ground-water studies which were already being made in Kansas by the U.S Geological Survey, the Kansas State Geological Survey, the Division of Sanitation of the Kansas Board of Health and the Division of Water Resources of the Kansas State Board of Agriculture.  

Canonical ensemble ground state and correlation entropy of Bose-Einstein condensate

NASA Astrophysics Data System (ADS)

Svidzinsky, Anatoly; Kim, Moochan; Agarwal, Girish; Scully, Marlan O.

2018-01-01

Constraint of a fixed total number of particles yields a correlation between the fluctuation of particles in different states in the canonical ensemble. Here we show that, below the temperature of Bose-Einstein condensation (BEC), the correlation part of the entropy of an ideal Bose gas is cancelled by the ground-state contribution. Thus, in the BEC region, the thermodynamic properties of the gas in the canonical ensemble can be described accurately in a simplified model which excludes the ground state and assumes no correlation between excited levels.

Role of electronic excited N2 in vibrational excitation of the N2 ground state at high latitudes

NASA Astrophysics Data System (ADS)

Campbell, L.; Cartwright, D. C.; Brunger, M. J.; Teubner, P. J. O.

2006-09-01

Vibrationally excited N2 is important in determining the ionospheric electron density and has also been proposed to play a role in the production of NO in disturbed atmospheres. We report here predictions of the absolute vibrational distributions in the ground electronic state of N2 produced by electron impact excitation, at noon and midnight under quiet geomagnetic conditions and disturbed conditions corresponding to the aurora IBCII+ and IBCIII+ at 60°N latitude and 0° longitude, at altitudes between 130 and 350 km. These predictions were obtained from a model which includes thermal excitation and direct electron impact excitation of the vibrational levels of the N2 ground state and its excited electronic states; radiative cascade from all excited electronic states to all vibrational levels of the ground electronic state; quenching by O, O2, and N2; molecular and ambipolar diffusion; and the dominant chemical reactions. Results from this study show that for both aurora and daytime electron environments: (1) cascade from the higher electronic states of N2 determines the population of the higher vibrational levels in the N2 ground state and (2) the effective ground state vibrational temperature for levels greater than 4 in N2 is predicted to be in the range 4000-13000 K for altitudes greater than 200 km. Correspondingly, the associated enhancement factor for the O+ reaction with vibrationally excited N2 to produce NO+ is predicted to increase with increasing altitude (up to a maximum at a height which increases with auroral strength) for both aurora and daytime environments and to increase with increasing auroral strength. The contribution of the cascade from the excited electronic states was evaluated and found to be relatively minor compared to the direct excitation process.

Application of partially coherent modes for studying generation of a Gaussian partially coherent laser beam

DOE Office of Scientific and Technical Information (OSTI.GOV)

Suvorov, A A

2010-10-15

The problem of steady-state generation of a Gaussian partially coherent beam in a stable-cavity laser is considered within the framework of the method of expansion of the radiation coherence function in partially coherent modes. We discuss the conditions whose fulfilment makes it possible to neglect the intermode beatings of the radiation field and the effect of the gain dispersion on the steady-state generation of multimode partially coherent radiation. Based on the simplified model, we solve the self-consistent problem of generation of a Gaussian partially coherent beam for the given laser pump conditions and the resonator parameters. The dependence of themore » beam characteristics (power, radius, etc.) on the active medium properties and the resonator parameters is obtained. (laser beams)« less

Extremal states of positive partial transpose in a system of three qubits

NASA Astrophysics Data System (ADS)

Steensgaard Garberg, Øyvind; Irgens, Børge; Myrheim, Jan

2013-03-01

We have studied mixed states in the system of three qubits with the property that all their partial transposes are positive; these are called PPT states. We classify a PPT state by the ranks of the state itself and its three single partial transposes. In random numerical searches, we find entangled PPT states with a large variety of rank combinations. For ranks equal to five or higher, we find both extremal and nonextremal PPT states of nearly every rank combination, with the restriction that the square sum of the four ranks of an extremal PPT state can be at most 193. We have studied especially the rank-four entangled PPT states, which are found to have rank four for every partial transpose. These states are all extremal because of the previously known result that every PPT state of rank three or less is separable. We find two distinct classes of rank-4444 entangled PPT states, identified by a real valued quadratic expression invariant under local SL(2,C) transformations, mathematically equivalent to Lorentz transformations. This quadratic Lorentz invariant is nonzero for one class of states (type I in our terminology) and zero for the other class (type II). The previously known states based on unextendible product bases are a nongeneric subclass of the type-I states. We present analytical constructions of states of both types, general enough to reproduce all the rank-4444 PPT states we have found numerically. We can not exclude the possibility that there exist nongeneric rank-four PPT states that we do not find in our random numerical searches.

E2/M1 mixing ratios in transitions from the gamma vibrational bands to the ground state rotational bands of 102, 104, 106, 108Mo, 108, 110, 112Ru, and 112, 114, 116Pd

NASA Astrophysics Data System (ADS)

Eldridge, J. M.; Fenker, B.; Hamilton, J. H.; Goodin, C.; Zachary, C. J.; Wang, E.; Ramayya, A. V.; Daniel, A. V.; Ter-Akopian, G. M.; Oganessian, Yu. Ts.; Luo, Y. X.; Rasmussen, J. O.; Zhu, S. J.

2018-02-01

E2/ M1 mixing ratios have been measured for transitions from states in the γ vibrational bands ( I+_{γ}) to states in the ground state bands (I+ or [I-1]+) of the neutron rich, even-even, deformed isotopes, 102, 104, 106, 108Mo, 108, 110, 112Ru, and 112, 114, 116Pd, including from states as high as 9+_{γ}. These measurements were done using the GAMMASPHERE detector array, which, at the time of the experiment, had 101 working HPGe detectors, arranged at 64 different angles. A 62 μCi source of 252Cf was placed inside GAMMASPHERE yielding 5.7× 10^{11} γ-γ-γ and higher coincidence events. The angular correlations between the transitions from the γ-bands to the ground bands, and the pure E2 transitions within the ground band were then measured. These angular correlations yielded the mixing ratios, demonstrating that these transitions are pure or nearly pure E2, in agreement with theory. In order to correct for possible attenuation due to the lifetime of the intermediate state in these correlations, the g-factors of the intermediate states needed to be known. Therefore, the g-factors of the 2+ states in the ground state band have been measured.

76 FR 35344 - Airworthiness Directives; Costruzioni Aeronautiche Tecnam srl Model P2006T Airplanes

Federal Register 2010, 2011, 2012, 2013, 2014

2011-06-17

... retraction/extension ground checks performed on the P2006T, a loose Seeger ring was found on the nose landing... specified products. The MCAI states: During Landing Gear retraction/extension ground checks performed on the... airworthiness information (MCAI) states: During Landing Gear retraction/extension ground checks performed on the...

Ground Water Atlas of the United States: Introduction and national summary

USGS Publications Warehouse

Miller, James A.

1999-01-01

The Ground Water Atlas of the United States provides a summary of the most important information available for each principal aquifer, or rock unit that will yield usable quantities of water to wells, throughout the 50 States, Puerto Rico, and the U.S. Virgin Islands. The Atlas is an outgrowth of the Regional Aquifer-System Analysis (RASA) program of the U.S. Geological Survey (USGS), a program that investigated 24 of the most important aquifers and aquifer systems of the Nation and one in the Caribbean Islands (fig. 1). The objectives of the RASA program were to define the geologic and hydrologic frameworks of each aquifer system, to assess the geochemistry of the water in the system, to characterize the ground-water flow system, and to describe the effects of development on the flow system. Although the RASA studies did not cover the entire Nation, they compiled much of the data needed to make the National assessments of ground-water resources presented in the Ground Water Atlas of the United States. The Atlas, however, describes the location, extent, and geologic and hydrologic characteristics of all the important aquifers in the United States, including those not studied by the RASA program. The Atlas is written so that it can be understood by readers who are not hydrologists. Simple language is used to explain technical terms. The principles that control the presence, movement, and chemical quality of ground water in different climatic, topographic, and geologic settings are clearly illustrated. The Atlas is, therefore, useful as a teaching tool for introductory courses in hydrology or hydrogeology at the college level and as an overview of ground-water conditions for consultants who need information about an individual aquifer. It also serves as an introduction to regional and National ground-water resources for lawmakers, personnel of local, State, or Federal agencies, or anyone who needs to understand ground-water occurrence, movement, and quality. The purpose of the Ground Water Atlas of the United States is to summarize, in one publication with a common format, the most important ground-water information that has been collected over many years by the USGS, other Federal agencies, and State and local water management agencies. The purpose of this introductory chapter is to describe the content of the Atlas; to discuss the characteristics, use, and limitations of the maps and other types of illustrations used in the different chapters of the book; to summarize the locations of the principal aquifers on a Nationwide map; and to give an example of an aquifer in each principal hydrogeologic setting.

Population trends and survival of nesting green sea turtles Chelonia mydas on Aves Island, Venezuela

USGS Publications Warehouse

Garcia-Cruz, Marco A.; Lampo, Margarita; Peñaloza, Claudia L.; Kendall, William L.; Solé, Genaro; Rodriguez-Clark, Kathryn M.

2015-01-01

Long-term demographic data are valuable for assessing the effect of anthropogenic impacts on endangered species and evaluating recovery programs. Using a 2-state open robust design model, we analyzed mark-recapture data from green turtles Chelonia mydas sighted between 1979 and 2009 on Aves Island, Venezuela, a rookery heavily impacted by human activities before it was declared a wildlife refuge in 1972. Based on the encounter histories of 7689 nesting females, we estimated the abundance, annual survival, and remigration intervals for this population. Female survival varied from 0.14-0.91, with a mean of 0.79, which is low compared to survival of other populations from the Caribbean (mean = 0.84) and Australia (mean = 0.95), even though we partially corrected for tag loss, which is known to negatively bias survival estimates. This supports prior suggestions that Caribbean populations in general, and the Aves Island population in particular, may be more strongly impacted than populations elsewhere. It is likely that nesters from this rookery are extracted while foraging in remote feeding grounds where hunting still occurs. Despite its relatively low survival, the nesting population at Aves Island increased during the past 30 years from approx. 500 to >1000 nesting females in 2009. Thus, this population, like others in the Caribbean and the Atlantic, seems to be slowly recovering following protective management. Although these findings support the importance of long-term conservation programs aimed at protecting nesting grounds, they also highlight the need to extend management actions to foraging grounds where human activities may still impact green turtle populations.

Multichannel modeling and two-photon coherent transfer paths in NaK

NASA Astrophysics Data System (ADS)

Schulze, T. A.; Temelkov, I. I.; Gempel, M. W.; Hartmann, T.; Knöckel, H.; Ospelkaus, S.; Tiemann, E.

2013-08-01

We explore possible pathways for the creation of ultracold polar NaK molecules in their absolute electronic and rovibrational ground state starting from ultracold Feshbach molecules. In particular, we present a multichannel analysis of the electronic ground and K(4p)+Na(3s) excited-state manifold of NaK, analyze the spin character of both the Feshbach molecular state and the electronically excited intermediate states and discuss possible coherent two-photon transfer paths from Feshbach molecules to rovibronic ground-state molecules. The theoretical study is complemented by the demonstration of stimulated Raman adiabatic passage from the X1Σ+(v=0) state to the a3Σ+ manifold on a molecular beam experiment.

Vision-based localization for on-orbit servicing of a partially cooperative satellite

NASA Astrophysics Data System (ADS)

Oumer, Nassir W.; Panin, Giorgio; Mülbauer, Quirin; Tseneklidou, Anastasia

2015-12-01

This paper proposes ground-in-the-loop, model-based visual localization system based on transmitted images to ground, to aid rendezvous and docking maneuvers between a servicer and a target satellite. In particular, we assume to deal with a partially cooperative target, i.e. passive and without fiducial markers, but supposed at least to keep a controlled attitude, up to small fluctuations, so that the approach mainly involves translational motion. For the purpose of localization, video cameras provide an effective and relatively inexpensive solution, working at a wide range of distances with an increasing accuracy and robustness during the approach. However, illumination conditions in space are especially challenging, due to the direct sunlight exposure and to the glossy surface of a satellite, that creates strong reflections and saturations and therefore a high level of background clutter and missing detections. We employ a monocular camera for mid-range tracking (20 - 5 m) and stereo camera at close-range (5 - 0.5 m), with the respective detection and tracking methods, both using intensity edges and robustly dealing with the above issues. Our tracking system has been extensively verified at the facility of the European Proximity Operations Simulator (EPOS) of DLR, which is a very realistic ground simulation able to reproduce sunlight conditions through a high power floodlight source, satellite surface properties using multilayer insulation foils, as well as orbital motion trajectories with ground-truth data, by means of two 6 DOF industrial robots. Results from this large dataset show the effectiveness and robustness of our method against the above difficulties.

Graphene ground states

NASA Astrophysics Data System (ADS)

Friedrich, Manuel; Stefanelli, Ulisse

2018-06-01

Graphene is locally two-dimensional but not flat. Nanoscale ripples appear in suspended samples and rolling up often occurs when boundaries are not fixed. We address this variety of graphene geometries by classifying all ground-state deformations of the hexagonal lattice with respect to configurational energies including two- and three-body terms. As a consequence, we prove that all ground-state deformations are either periodic in one direction, as in the case of ripples, or rolled up, as in the case of nanotubes.

Construction of ground-state preserving sparse lattice models for predictive materials simulations

NASA Astrophysics Data System (ADS)

Huang, Wenxuan; Urban, Alexander; Rong, Ziqin; Ding, Zhiwei; Luo, Chuan; Ceder, Gerbrand

2017-08-01

First-principles based cluster expansion models are the dominant approach in ab initio thermodynamics of crystalline mixtures enabling the prediction of phase diagrams and novel ground states. However, despite recent advances, the construction of accurate models still requires a careful and time-consuming manual parameter tuning process for ground-state preservation, since this property is not guaranteed by default. In this paper, we present a systematic and mathematically sound method to obtain cluster expansion models that are guaranteed to preserve the ground states of their reference data. The method builds on the recently introduced compressive sensing paradigm for cluster expansion and employs quadratic programming to impose constraints on the model parameters. The robustness of our methodology is illustrated for two lithium transition metal oxides with relevance for Li-ion battery cathodes, i.e., Li2xFe2(1-x)O2 and Li2xTi2(1-x)O2, for which the construction of cluster expansion models with compressive sensing alone has proven to be challenging. We demonstrate that our method not only guarantees ground-state preservation on the set of reference structures used for the model construction, but also show that out-of-sample ground-state preservation up to relatively large supercell size is achievable through a rapidly converging iterative refinement. This method provides a general tool for building robust, compressed and constrained physical models with predictive power.

Comparative analysis of proton- and neutron-halo breakups

NASA Astrophysics Data System (ADS)

Mukeru, B.

2018-06-01

A detailed analysis of the proton- and neutron-halo breakup cross sections is presented. Larger neutron-halo breakup cross sections than proton-halo breakup cross sections are obtained. This is found to be mainly due to the projectile structure, namely the ground state wave function and the dipole electric response function. It is also found that the continuum–continuum couplings are stronger in the proton-halo breakup than in the neutron-halo breakup. The increase of proton- and neutron-halo ground state separation energy slightly strengthens these couplings in the proton- and neutron-halo total and nuclear breakups, while they are weakened in the proton- and neutron-halo Coulomb breakups. The Coulomb-nuclear interference remains strongly destructive in both proton- and neutron-halo breakups and this is independent of the ground state separation energy. The results also show that the increase of the neutron-halo ground state separation energy decreases significantly the agreement between the proton- and neutron-halo breakup cross sections, both qualitatively and quantitatively. It is obtained that when the proton-halo ground state separation energy is increased by a factor of 4.380, the proton-halo breakup cross section is reduced by a factor of 4.392, indicating a clear proportionality. However, when the neutron-halo ground state separation energy is increased by the same factor, the neutron-halo total breakup cross section is reduced by a factor of 8.522.

Interband optical pulse injection locking of quantum dot mode-locked semiconductor laser.

PubMed

Kim, Jimyung; Delfyett, Peter J

2008-07-21

We experimentally demonstrate optical clock recovery from quantum dot mode-locked semiconductor lasers by interband optical pulse injection locking. The passively mode-locked slave laser oscillating on the ground state or the first excited state transition is locked through the injection of optical pulses generated via the opposite transition bands, i.e. the first excited state or the ground state transition from the hybridly mode-locked master laser, respectively. When an optical pulse train generated via the first excited state from the master laser is injected to the slave laser oscillating via ground state, the slave laser shows an asymmetric locking bandwidth around the nominal repetition rate of the slave laser. In the reverse injection case of, i.e. the ground state (master laser) to the first excited state (slave laser), the slave laser does not lock even though both lasers oscillate at the same cavity frequency. In this case, the slave laser only locks to higher injection rates as compared to its own nominal repetition rate, and also shows a large locking bandwidth of 6.7 MHz.

Systematic study of α preformation probability of nuclear isomeric and ground states

NASA Astrophysics Data System (ADS)

Sun, Xiao-Dong; Wu, Xi-Jun; Zheng, Bo; Xiang, Dong; Guo, Ping; Li, Xiao-Hua

2017-01-01

In this paper, based on the two-potential approach combining with the isospin dependent nuclear potential, we systematically compare the α preformation probabilities of odd-A nuclei between nuclear isomeric states and ground states. The results indicate that during the process of α particle preforming, the low lying nuclear isomeric states are similar to ground states. Meanwhile, in the framework of single nucleon energy level structure, we find that for nuclei with nucleon number below the magic numbers, the α preformation probabilities of high-spin states seem to be larger than low ones. For nuclei with nucleon number above the magic numbers, the α preformation probabilities of isomeric states are larger than those of ground states. Supported by National Natural Science Foundation of China (11205083), Construct Program of Key Discipline in Hunan Province, Research Foundation of Education Bureau of Hunan Province, China (15A159), Natural Science Foundation of Hunan Province, China (2015JJ3103, 2015JJ2123), Innovation Group of Nuclear and Particle Physics in USC, Hunan Provincial Innovation Foundation for Postgraduate (CX2015B398)

22 CFR 9b.6 - Grounds for denial, revocation, or non-renewal of Department of State press building passes.

Code of Federal Regulations, 2010 CFR

2010-04-01

... of Department of State press building passes. 9b.6 Section 9b.6 Foreign Relations DEPARTMENT OF STATE GENERAL REGULATIONS GOVERNING DEPARTMENT OF STATE PRESS BUILDING PASSES § 9b.6 Grounds for denial, revocation, or non-renewal of Department of State press building passes. In consultation with the Bureau of...

Creation of a strongly dipolar gas of ultracold ground-state 23 Na87 Rb molecules

NASA Astrophysics Data System (ADS)

Guo, Mingyang; Zhu, Bing; Lu, Bo; Ye, Xin; Wang, Fudong; Wang, Dajun; Vexiau, Romain; Bouloufa-Maafa, Nadia; Quéméner, Goulven; Dulieu, Olivier

2016-05-01

We report on successful creation of an ultracold sample of ground-state 23 Na87 Rb molecules with a large effective electric dipole moment. Through a carefully designed two-photon Raman process, we have successfully transferred the magneto-associated Feshbach molecules to the singlet ground state with high efficiency, obtaining up to 8000 23 Na87 Rb molecules with peak number density over 1011 cm-3 in their absolute ground-state level. With an external electric field, we have induced an effective dipole moment over 1 Debye, making 23 Na87 Rb the most dipolar ultracold particle ever achieved. Contrary to the expectation, we observed a rather fast population loss even for 23 Na87 Rb in the absolute ground state with the bi-molecular exchange reaction energetically forbidden. The origin for the short lifetime and possible ways of mitigating it are currently under investigation. Our achievements pave the way toward investigation of ultracold bosonic molecules with strong dipolar interactions. This work is supported by the Hong Kong RGC CUHK404712 and the ANR/RGC Joint Research Scheme ACUHK403/13.

Smart darting diffusion Monte Carlo: Applications to lithium ion-Stockmayer clusters

NASA Astrophysics Data System (ADS)

Christensen, H. M.; Jake, L. C.; Curotto, E.

2016-05-01

In a recent investigation [K. Roberts et al., J. Chem. Phys. 136, 074104 (2012)], we have shown that, for a sufficiently complex potential, the Diffusion Monte Carlo (DMC) random walk can become quasiergodic, and we have introduced smart darting-like moves to improve the sampling. In this article, we systematically characterize the bias that smart darting moves introduce in the estimate of the ground state energy of a bosonic system. We then test a simple approach to eliminate completely such bias from the results. The approach is applied for the determination of the ground state of lithium ion-n-dipoles clusters in the n = 8-20 range. For these, the smart darting diffusion Monte Carlo simulations find the same ground state energy and mixed-distribution as the traditional approach for n < 14. In larger systems we find that while the ground state energies agree quantitatively with or without smart darting moves, the mixed-distributions can be significantly different. Some evidence is offered to conclude that introducing smart darting-like moves in traditional DMC simulations may produce a more reliable ground state mixed-distribution.

Hydrogeologic investigation and simulation of ground-water flow in the Upper Floridan Aquifer of north-central Florida and southwestern Georgia and delineation of contributing areas for selected city of Tallahassee, Florida, water-supply wells

USGS Publications Warehouse

Davis, J. Hal

1996-01-01

A 4-year investigation of the Upper Floridan aquifer and ground-water flow system in Leon County, Florida, and surrounding counties of north-central Florida and southwestern Georgia began in 1990. The purpose of the investigation was to describe the ground-water flow system and to delineate the contributing areas to selected City of Tallahassee, Florida, water-supply wells. The investigation was prompted by the detection of low levels of tetrachloroethylene in ground-water samples collected from several of the city's water-supply wells. Hydrologic data and previous studies indicate that; ground-water flow within the Upper Floridan aquifer can be considered steady-state; the Upper Floridan aquifer is a single water-bearing unit; recharge is from precipitation; and that discharge occurs as spring flow, leakage to rivers, leakage to the Gulf of Mexico, and pumpage. Measured transmissivities of the aquifer ranged from 1,300 ft2/d (feet squared per day) to 1,300,000 ft2/d. Steady-state ground-water flow in the Upper Floridan aquifer was simulated using a three-dimensional ground- water flow model. Transmissivities ranging from less than 5,000 ft2/d to greater than 11,000,000 ft2/d were required to calibrate to observed conditions. Recharge rates used in the model ranged from 18.0 inches per year in areas where the aquifer was unconfined to less than 2 inches per year in broad areas where the aquifer was confined. Contributing areas to five Tallahassee water-supply wells were simulated by particle- tracking techniques. Particles were seeded in model cells containing pumping wells then tracked backwards in time toward recharge areas. The contributing area for each well was simulated twice, once assuming a porosity of 25 percent and once assuming a porosity of 5 percent. A porosity of 25 percent is considered a reasonable average value for the Upper Floridan aquifer; the 5 percent porosity simulated the movement of ground-water through only solution-enhanced bedding plains and fractures. The contributing areas were generally elliptical in shape, reflecting the influence of the sloping potentiometric surface. The contributing areas delineated for a 5 percent porosity were always much larger than those determined using a 25 percent porosity. The lowest average ground-water velocity computed within a contributing area, using a 25 percent porosity, was 1.0 ft/d (foot per day) and the highest velocity was 1.6 ft/d. The lowest average ground-water velocity, determined using a 5 percent porosity, was 2.4 ft/d and the highest was 7.4 ft/d. The contributing areas for each of the five wells was also determined analytically and compared to the model-derived areas. The upgradient width of the simulated contributing areas were larger than the upgradient width of the analytically determined contributing areas for four of the five wells. The model could more accurately delineate contributing areas because of the ability to simulate wells as partially penetrating and by incorporating complex, three-dimensional aquifer characteristics, which the analytical method could not.

Relativistic many-body calculation of energies, transition rates, lifetimes, and multipole polarizabilities in Cs-like La iii

NASA Astrophysics Data System (ADS)

Safronova, U. I.; Safronova, M. S.

2014-05-01

Excitation energies of the [Xe]nd (n =5-9), [Xe]ns (n =6-10), [Xe]np (n =6-9), [Xe]nf (n =4-8), and [Xe]ng (n =5-8) states in La iii, where [Xe] = 1s22s22p63s23p63d104s24p64d105s25p6, are evaluated. Electric dipole matrix elements for the allowed transitions between the low-lying [Xe]nd, [Xe]ns, [Xe]np, [Xe]nf, and [Xe]ng states in the La iii ion are calculated using the high-precision relativistic all-order method where all single, double, and partial triple excitations of the Dirac-Fock wave functions are included to all orders of perturbation theory. Recommended values are provided for a large number of electric dipole matrix elements, oscillator strengths, transition rates, and lifetimes. Scalar and tensor polarizabilities of the states listed above are evaluated. The uncertainties of the recommended values are estimated. Electric quadrupole and magnetic dipole matrix elements are calculated to determine lifetimes of the 5d5/2 and 6s metastable levels. The ground-state E1, E2, and E3 static polarizabilities are calculated. This work provides recommended values critically evaluated for their accuracy for a number of La iii atomic properties for use in planning and analysis of various experiments as well as theoretical modeling.

Entanglement convertibility by sweeping through the quantum phases of the alternating bonds XXZ chain

PubMed Central

Tzeng, Yu-Chin; Dai, Li; Chung, Ming-Chiang; Amico, Luigi; Kwek, Leong-Chuan

2016-01-01

We study the entanglement structure and the topological edge states of the ground state of the spin-1/2 XXZ model with bond alternation. We employ parity-density matrix renormalization group with periodic boundary conditions. The finite-size scaling of Rényi entropies S2 and S∞ are used to construct the phase diagram of the system. The phase diagram displays three possible phases: Haldane type (an example of symmetry protected topological ordered phases), Classical Dimer and Néel phases, the latter bounded by two continuous quantum phase transitions. The entanglement and non-locality in the ground state are studied and quantified by the entanglement convertibility. We found that, at small spatial scales, the ground state is not convertible within the topological Haldane dimer phase. The phenomenology we observe can be described in terms of correlations between edge states. We found that the entanglement spectrum also exhibits a distinctive response in the topological phase: the effective rank of the reduced density matrix displays a specifically large “susceptibility” in the topological phase. These findings support the idea that although the topological order in the ground state cannot be detected by local inspection, the ground state response at local scale can tell the topological phases apart from the non-topological phases. PMID:27216970

Effects of solvent polarity on the absorption and fluorescence spectra of chlorogenic acid and caffeic acid compounds: determination of the dipole moments.

PubMed

Belay, Abebe; Libnedengel, Ermias; Kim, Hyung Kook; Hwang, Yoon-Hwae

2016-02-01

The effects of solvent polarity on absorption and fluorescence spectra of biologically active compounds (chlorogenic acid (CGA) and caffeic acids (CA)) have been investigated. In both spectra pronounced solvatochromic effects were observed with shift of emission peaks larger than the corresponding UV-vis electronic absorption spectra. From solvatochromic theory the ground and excited-state dipole moments were determined experimentally and theoretically. The differences between the excited and ground state dipole moment determined by Bakhshiev, Kawski-Chamma-Viallet and Reichardt equations are quite similar. The ground and excited-state dipole moments were determined by theoretical quantum chemical calculation using density function theory (DFT) method (Gaussian 09) and were also similar to the experimental results. The HOMO-LUMO energy band gaps for CGA and CFA were calculated and found to be 4.1119 and 1.8732 eV respectively. The results also indicated the CGA molecule is more stable than that of CFA. It was also observed that in both compounds the excited state possesses a higher dipole moment than that of the ground state. This confirms that the excited state of the hydroxycinnamic compounds is more polarized than that of the ground state and therefore is more sensitive to the solvent. Copyright © 2015 John Wiley & Sons, Ltd.

Investigation of the electronic structure of Be2+He and Be+He, and static dipole polarisabilities of the helium atom

NASA Astrophysics Data System (ADS)

Dhiflaoui, J.; Bejaoui, M.; Farjallah, M.; Berriche, H.

2018-05-01

The potential energy and spectroscopic constants of the ground and many excited states of the Be+He van der Waals system have been investigated using a one-electron pseudo-potential approach, which is used to replace the effect of the Be2+ core and the electron-He interactions by effective potentials. Furthermore, the core-core interactions are incorporated. This permits the reduction of the number of active electrons of the Be+He van der Waals system to only one electron. Therefore, the potential energy of the ground state as well as the excited states is performed at the SCF level and considering the spin-orbit interaction. The core-core interaction for Be2+He ground state is included using accurate CCSD (T) calculations. Then, the spectroscopic properties of the Be+He electronic states are extracted and compared with the previous theoretical and experimental studies. This comparison has shown a very good agreement for the ground and the first excited states. Moreover, the transition dipole moment has been determined for a large and dense grid of internuclear distances including the spin orbit effect. In addition, a vibrational spacing analysis for the Be2+He and Be+He ground states is performed to extract the He atomic polarisability.

Fragile singlet ground-state magnetism in the pyrochlore osmates R 2 Os 2 O 7 ( R = Y and Ho)

DOE PAGES

Zhao, Z. Y.; Calder, S.; Aczel, A. A.; ...

2016-04-25

The singlet ground state magnetism in pyrochlore osmates Y 2Os 2O 7 and Ho 2Os 2O 7 is studied by DC and AC susceptibility, specific heat, and neutron powder diffraction measurements. Despite the expected non-magnetic singlet in the strong spin-orbit coupling (SOC) limit for Os 4+ (5d 4), Y 2Os 2O 7 exhibits a spin-glass (SG) ground state below 4 K with weak magnetism, suggesting possible proximity to a quantum phase transition between the non-magnetic state in the strong SOC limit and the magnetic state in the strong superexchange limit. Ho 2Os 2O 7 has the same structural distortion asmore » occurs in Y 2Os 2O 7. However, the Os sublattice in Ho 2Os 2O 7 shows long- range magnetic ordering below 36 K. We find that the sharp difference of the magnetic ground state between Y 2Os 2O 7 and Ho 2Os 2O 7 signals the singlet ground state magnetism in R 2 Os 2 O 7 is fragile and can be disturbed by the weak 4f—5d interactions.« less

Entanglement convertibility by sweeping through the quantum phases of the alternating bonds XXZ chain.

PubMed

Tzeng, Yu-Chin; Dai, Li; Chung, Ming-Chiang; Amico, Luigi; Kwek, Leong-Chuan

2016-05-24

We study the entanglement structure and the topological edge states of the ground state of the spin-1/2 XXZ model with bond alternation. We employ parity-density matrix renormalization group with periodic boundary conditions. The finite-size scaling of Rényi entropies S2 and S∞ are used to construct the phase diagram of the system. The phase diagram displays three possible phases: Haldane type (an example of symmetry protected topological ordered phases), Classical Dimer and Néel phases, the latter bounded by two continuous quantum phase transitions. The entanglement and non-locality in the ground state are studied and quantified by the entanglement convertibility. We found that, at small spatial scales, the ground state is not convertible within the topological Haldane dimer phase. The phenomenology we observe can be described in terms of correlations between edge states. We found that the entanglement spectrum also exhibits a distinctive response in the topological phase: the effective rank of the reduced density matrix displays a specifically large "susceptibility" in the topological phase. These findings support the idea that although the topological order in the ground state cannot be detected by local inspection, the ground state response at local scale can tell the topological phases apart from the non-topological phases.

Fragile singlet ground-state magnetism in the pyrochlore osmates R 2 Os 2 O 7 ( R = Y and Ho)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhao, Z. Y.; Calder, S.; Aczel, A. A.

The singlet ground state magnetism in pyrochlore osmates Y 2Os 2O 7 and Ho 2Os 2O 7 is studied by DC and AC susceptibility, specific heat, and neutron powder diffraction measurements. Despite the expected non-magnetic singlet in the strong spin-orbit coupling (SOC) limit for Os 4+ (5d 4), Y 2Os 2O 7 exhibits a spin-glass (SG) ground state below 4 K with weak magnetism, suggesting possible proximity to a quantum phase transition between the non-magnetic state in the strong SOC limit and the magnetic state in the strong superexchange limit. Ho 2Os 2O 7 has the same structural distortion asmore » occurs in Y 2Os 2O 7. However, the Os sublattice in Ho 2Os 2O 7 shows long- range magnetic ordering below 36 K. We find that the sharp difference of the magnetic ground state between Y 2Os 2O 7 and Ho 2Os 2O 7 signals the singlet ground state magnetism in R 2 Os 2 O 7 is fragile and can be disturbed by the weak 4f—5d interactions.« less

Spin-orbit driven magnetic insulating state with J eff=1/2 character in a 4d oxide

DOE PAGES

Calder, S.; Li, Ling; Okamoto, Satoshi; ...

2015-11-30

The unusual magnetic and electronic ground states of 5d iridates has been shown to be driven by intrinsically enhanced spin-orbit coupling (SOC). The influence of appreciable but reduced SOC in creating the manifested magnetic insulating states in 4d oxides is less clear, with one hurdle being the existence of such compounds. Here we present experimental and theoretical results on Sr 4RhO 6 that reveal SOC dominated behavior. Neutron measurements show the octahedra are both spatially separated and locally ideal, making the electronic ground state susceptible to alterations by SOC. Magnetic ordering is observed with a similar structure to an analogousmore » J eff=1/2 Mott iridate. We consider the underlying role of SOC in this rhodate with density functional theory and x-ray absorption spectroscopy and find a magnetic insulating ground state with J eff =1/2 character.The unusual magnetic and electronic ground states of 5d iridates have been shown to be driven by intrinsically enhanced spin-orbit coupling (SOC). The influence of appreciable but reduced SOC in creating the manifested magnetic insulating states in 4d oxides is less clear, with one hurdle being the existence of such compounds. Here, we present experimental and theoretical results on Sr 4RhO 6 that reveal SOC dominated behavior. Neutron measurements show the octahedra are both spatially separated and locally ideal, making the electronic ground state susceptible to alterations by SOC. Magnetic ordering is observed with a similar structure to an analogous J eff=1/2 Mott iridate. We consider the underlying role of SOC in this rhodate with density functional theory and x-ray absorption spectroscopy, and find a magnetic insulating ground state with J eff=12 character.« less

Spin-Orbit Coupling Controlled J = 3 / 2 Electronic Ground State in 5 d 3 Oxides

DOE Office of Scientific and Technical Information (OSTI.GOV)

Taylor, A. E.; Calder, S.; Morrow, R.

Entanglement of spin and orbital degrees of freedom drives the formation of novel quantum and topological physical states. Here we report resonant inelastic x-ray scattering measurements of the transition metal oxides Ca3LiOsO6 and Ba2YOsO6, which reveals a dramatic spitting of the t2g manifold. We invoke an intermediate coupling approach that incorporates both spin-orbit coupling and electron-electron interactions on an even footing and reveal that the ground state of 5d3-based compounds, which has remained elusive in previously applied models, is a novel spin-orbit entangled J=3/2 electronic ground state. This work reveals the hidden diversity of spin-orbit controlled ground states in 5dmore » systems and introduces a new arena in the search for spin-orbit controlled phases of matter.« less

Ground-State Wave Function with Interactions between Different Species in M-Component Miscible Bose-Einstein Condensates

NASA Astrophysics Data System (ADS)

Kohno, Wataru; Kirikoshi, Akimitsu; Kita, Takafumi

2018-03-01

We construct a variational ground-state wave function of weakly interacting M-component Bose-Einstein condensates beyond the mean-field theory by incorporating the dynamical 3/2-body processes, where one of the two colliding particles drops into the condensate and vice versa. Our numerical results with various masses and particle numbers show that the 3/2-body processes between different particles make finite contributions to lowering the ground-state energy, implying that many-body correlation effects between different particles are essential even in the weak-coupling regime of the Bose-Einstein condensates. We also consider the stability condition for 2-component miscible states using the new ground-state wave function. Through this calculation, we obtain the relation UAB2/UAAUBB < 1 + α , where Uij is the effective contact potential between particles i and j and α is the correction, which originates from the 3/2- and 2-body processes.

Electronic properties of RDX and HMX: Compton scattering experiment and first-principles calculation.

PubMed

Ahuja, B L; Jain, Pradeep; Sahariya, Jagrati; Heda, N L; Soni, Pramod

2013-07-11

The first-ever electron momentum density (EMD) measurements of explosive materials, namely, RDX (1,3,5-trinitro-1,3,5-triazacyclohexane, (CH2-N-NO2)3) and HMX (1,3,5,7-tetranitro-1,3,5,7-tetraazacyclooctane, (CH2-N-NO2)4), have been reported using a 740 GBq (137)Cs Compton spectrometer. Experimental Compton profiles (CPs) are compared with the EMDs derived from linear combination of atomic orbitals with density functional theory. It is found that the CPs deduced from generalized gradient approximation (GGA) with Wu-Cohen exchange energies give a better agreement with the corresponding experimental profiles than those from local density approximation and other schemes of GGA. Further, Mulliken population, energy bands, partial and total density of states, and band gap have also been reported using GGA calculations. Present ground state calculations unambiguously show large band gap semiconductor nature of both RDX and HMX. A similar type of bonding in these materials is uniquely established using Compton data and density of states. It is also outstandingly consistent with the Mulliken population, which predicts almost equal amount of charge transfer (0.84 and 0.83 e(-)) from H1 + H2 + N2 to C1 + N1 + O1 + O2 in both the explosives.

Oxalate analysis methodology for decayed wood

Treesearch

Carol A. Clausen; William Kenealy; Patricia K. Lebow

2008-01-01

Oxalate from partially decayed southern pine wood was analyzed by HPLC or colorimetric assay. Oxalate extraction efficiency, assessed by comparing analysis of whole wood cubes with ground wood, showed that both wood geometries could be extracted with comparable efficiency. To differentiate soluble oxalate from total oxalate, three extraction methods were assessed,...

Partial oxidation (“aging”) and surface modification decrease the toxicity of nano-sized zero valent iron.

EPA Science Inventory

Nanosize zero-valent iron (nZVI) is used as a redox-active catalyst for in situ remediation of contaminated ground waters. In aqueous environments, nZVI oxidizes over time (i.e., “ages”) to magnetite and other oxides. For remediation, hi...

Dynamical Casimir-Polder force on a partially dressed atom near a conducting wall

DOE Office of Scientific and Technical Information (OSTI.GOV)

Messina, Riccardo; Vasile, Ruggero; Passante, Roberto

2010-12-15

We study the time evolution of the Casimir-Polder force acting on a neutral atom in front of a perfectly conducting plate, when the system starts its unitary evolution from a partially dressed state. We solve the Heisenberg equations for both atomic and field quantum operators, exploiting a series expansion with respect to the electric charge and an iterative technique. After discussing the behavior of the time-dependent force on an initially partially dressed atom, we analyze a possible experimental scheme to prepare the partially dressed state and the observability of this new dynamical effect.

Entanglement and nonclassicality for multimode radiation-field states

NASA Astrophysics Data System (ADS)

Ivan, J. Solomon; Chaturvedi, S.; Ercolessi, E.; Marmo, G.; Morandi, G.; Mukunda, N.; Simon, R.

2011-03-01

Nonclassicality in the sense of quantum optics is a prerequisite for entanglement in multimode radiation states. In this work we bring out the possibilities of passing from the former to the latter, via action of classicality preserving systems like beam splitters, in a transparent manner. For single-mode states, a complete description of nonclassicality is available via the classical theory of moments, as a set of necessary and sufficient conditions on the photon number distribution. We show that when the mode is coupled to an ancilla in any coherent state, and the system is then acted upon by a beam splitter, these conditions turn exactly into signatures of negativity under partial transpose (NPT) entanglement of the output state. Since the classical moment problem does not generalize to two or more modes, we turn in these cases to other familiar sufficient but not necessary conditions for nonclassicality, namely the Mandel parameter criterion and its extensions. We generalize the Mandel matrix from one-mode states to the two-mode situation, leading to a natural classification of states with varying levels of nonclassicality. For two-mode states we present a single test that can, if successful, simultaneously show nonclassicality as well as NPT entanglement. We also develop a test for NPT entanglement after beam-splitter action on a nonclassical state, tracing carefully the way in which it goes beyond the Mandel nonclassicality test. The result of three-mode beam-splitter action after coupling to an ancilla in the ground state is treated in the same spirit. The concept of genuine tripartite entanglement, and scalar measures of nonclassicality at the Mandel level for two-mode systems, are discussed. Numerous examples illustrating all these concepts are presented.

Exact ground-state correlation functions of an atomic-molecular Bose–Einstein condensate model

NASA Astrophysics Data System (ADS)

Links, Jon; Shen, Yibing

2018-05-01

We study the ground-state properties of an atomic-molecular Bose–Einstein condensate model through an exact Bethe Ansatz solution. For a certain range of parameter choices, we prove that the ground-state Bethe roots lie on the positive real-axis. We then use a continuum limit approach to obtain a singular integral equation characterising the distribution of these Bethe roots. Solving this equation leads to an analytic expression for the ground-state energy. The form of the expression is consistent with the existence of a line of quantum phase transitions, which has been identified in earlier studies. This line demarcates a molecular phase from a mixed phase. Certain correlation functions, which characterise these phases, are then obtained through the Hellmann–Feynman theorem.

Deep Wavelet Scattering for Quantum Energy Regression

NASA Astrophysics Data System (ADS)

Hirn, Matthew

Physical functionals are usually computed as solutions of variational problems or from solutions of partial differential equations, which may require huge computations for complex systems. Quantum chemistry calculations of ground state molecular energies is such an example. Indeed, if x is a quantum molecular state, then the ground state energy E0 (x) is the minimum eigenvalue solution of the time independent Schrödinger Equation, which is computationally intensive for large systems. Machine learning algorithms do not simulate the physical system but estimate solutions by interpolating values provided by a training set of known examples {(xi ,E0 (xi) } i <= n . However, precise interpolations may require a number of examples that is exponential in the system dimension, and are thus intractable. This curse of dimensionality may be circumvented by computing interpolations in smaller approximation spaces, which take advantage of physical invariants. Linear regressions of E0 over a dictionary Φ ={ϕk } k compute an approximation E 0 as: E 0 (x) =∑kwkϕk (x) , where the weights {wk } k are selected to minimize the error between E0 and E 0 on the training set. The key to such a regression approach then lies in the design of the dictionary Φ. It must be intricate enough to capture the essential variability of E0 (x) over the molecular states x of interest, while simple enough so that evaluation of Φ (x) is significantly less intensive than a direct quantum mechanical computation (or approximation) of E0 (x) . In this talk we present a novel dictionary Φ for the regression of quantum mechanical energies based on the scattering transform of an intermediate, approximate electron density representation ρx of the state x. The scattering transform has the architecture of a deep convolutional network, composed of an alternating sequence of linear filters and nonlinear maps. Whereas in many deep learning tasks the linear filters are learned from the training data, here the physical properties of E0 (invariance to isometric transformations of the state x, stable to deformations of x) are leveraged to design a collection of linear filters ρx *ψλ for an appropriate wavelet ψ. These linear filters are composed with the nonlinear modulus operator, and the process is iterated upon so that at each layer stable, invariant features are extracted: ϕk (x) = ∥ | | ρx *ψλ1 | * ψλ2 | * ... *ψλm ∥ , k = (λ1 , ... ,λm) , m = 1 , 2 , ... The scattering transform thus encodes not only interactions at multiple scales (in the first layer, m = 1), but also features that encode complex phenomena resulting from a cascade of interactions across scales (in subsequent layers, m >= 2). Numerical experiments give state of the art accuracy over data bases of organic molecules, while theoretical results guarantee performance for the component of the ground state energy resulting from Coulombic interactions. Supported by the ERC InvariantClass 320959 Grant.

United States Marine Corps Reserve Prior Service Recruiting: A Future Command for Partially Manning the Reserves

DTIC Science & Technology

2013-06-14

month, blackjack award, slugger award, heavy hitter award, centurion, and recruiter of the year.” Marine Corps recruiting duty is very similar to a...UNITED STATES MARINE CORPS RESERVE PRIOR SERVICE RECRUITING: A FUTURE COMMAND FOR PARTIALLY MANNING THE RESERVES A thesis...presented to the Faculty of the U.S. Army Command and General Staff College in partial fulfillment of the requirements for the degree MASTER OF

Mitigation of near-band balanced steady-state free precession through-plane flow artifacts using partial dephasing.

PubMed

Datta, Anjali; Cheng, Joseph Y; Hargreaves, Brian A; Baron, Corey A; Nishimura, Dwight G

2018-06-01

To mitigate artifacts from through-plane flow at the locations of steady-state stopbands in balanced steady-state free precession (SSFP) using partial dephasing. A 60° range in the phase accrual during a TR was created over the voxel by slightly unbalancing the slice-select dephaser. The spectral profiles of SSFP with partial dephasing for various constant flow rates and during pulsatile flow were simulated to determine if partial dephasing decreases through-plane flow artifacts originating near SSFP dark bands while maintaining on-resonant signal. Simulations were then validated in a flow phantom. Lastly, phase-cycled SSFP cardiac cine images were acquired with and without partial dephasing in six subjects. Partial dephasing decreased the strength and non-linearity of the dependence of the signal at the stopbands on the through-plane flow rate. It thus mitigated hyper-enhancement from out-of-slice signal contributions and transient-related artifacts caused by variable flow both in the phantom and in vivo. In six volunteers, partial dephasing noticeably decreased artifacts in all of the phase-cycled cardiac cine datasets. Partial dephasing can mitigate the flow artifacts seen at the stopbands in balanced SSFP while maintaining the sequence's desired signal. By mitigating hyper-enhancement and transient-related artifacts originating from the stopbands, partial dephasing facilitates robust multiple-acquisition phase-cycled SSFP in the heart. Magn Reson Med 79:2944-2953, 2018. © 2017 International Society for Magnetic Resonance in Medicine. © 2017 International Society for Magnetic Resonance in Medicine.

Infinite projected entangled-pair state algorithm for ruby and triangle-honeycomb lattices

NASA Astrophysics Data System (ADS)

Jahromi, Saeed S.; Orús, Román; Kargarian, Mehdi; Langari, Abdollah

2018-03-01

The infinite projected entangled-pair state (iPEPS) algorithm is one of the most efficient techniques for studying the ground-state properties of two-dimensional quantum lattice Hamiltonians in the thermodynamic limit. Here, we show how the algorithm can be adapted to explore nearest-neighbor local Hamiltonians on the ruby and triangle-honeycomb lattices, using the corner transfer matrix (CTM) renormalization group for 2D tensor network contraction. Additionally, we show how the CTM method can be used to calculate the ground-state fidelity per lattice site and the boundary density operator and entanglement entropy (EE) on an infinite cylinder. As a benchmark, we apply the iPEPS method to the ruby model with anisotropic interactions and explore the ground-state properties of the system. We further extract the phase diagram of the model in different regimes of the couplings by measuring two-point correlators, ground-state fidelity, and EE on an infinite cylinder. Our phase diagram is in agreement with previous studies of the model by exact diagonalization.

A spectroscopic study of the molecular interactions of harmane with pyrimidine and other diazines.

PubMed

Muñoz, M A; Guardado, P; Galán, M; Carmona, C; Balón, M

2000-01-17

FTIR, UV-vis, steady state and time-resolved fluorescence measurements show that harmane (1-methyl-9H-pyrido/3,4-b/indole) interacts with pyrimidine and its isomers pyrazine and pyridazine in its ground and lowest singlet states. The mechanisms of interaction are dependent on both the structure of the diazine and the nature of the solvent. Thus, in a low polar solvent such as toluene, harmane forms ground state 1:1 hydrogen-bonded complexes with all the diazines. These complexes quench the fluorescence of harmane and diminish its fluorescence lifetime. Conversely, in buffered (pH 8.7) aqueous solutions, pyrimidine behaves differently from the other diazines. Thus, whereas pyrimidine only interacts with harmane in its ground state, pyrazine and pyridazine also interact in the excited state. The harmane-pyrimidine ground state interaction is an entropic controlled process. Therefore, we propose the formation of pi-pi stacked 1:1 complexes between these substrates. Association constants for the different types of complexes and quenching parameters are reported.

Strong interference effects in the resonant Auger decay of atoms induced by intense x-ray fields

DOE Office of Scientific and Technical Information (OSTI.GOV)

Demekhin, Philipp V.; Cederbaum, Lorenz S.

2011-02-15

The theory of resonant Auger decay of atoms in a high-intensity coherent x-ray pulse is presented. The theory includes the coupling between the ground state and the resonance due to an intense x-ray pulse, taking into account the decay of the resonance and the direct photoionization of the ground state, both populating the final ionic states coherently. The theory also considers the impact of the direct photoionization of the resonance state itself which typically populates highly excited ionic states. The combined action of the resonant decay and of the direct ionization of the ground state in the field induces amore » non-Hermitian time-dependent coupling between the ground and the ''dressed'' resonance stats. The impact of these competing processes on the total electron yield and on the 2s{sup 2}2p{sup 4}({sup 1}D)3p {sup 2}P spectator and 2s{sup 1}2p{sup 6} {sup 2}S participator Auger decay spectra of the Ne 1s{yields}3p resonance is investigated. The role of the direct photoionization of the ground state and of the resonance increases dramatically with the field intensity. This results in strong interference effects with distinct patterns in the electron spectra, which differ for the participator and spectator final states.« less

Improved Sensitivity Relations in State Constrained Optimal Control

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bettiol, Piernicola, E-mail: piernicola.bettiol@univ-brest.fr; Frankowska, Hélène, E-mail: frankowska@math.jussieu.fr; Vinter, Richard B., E-mail: r.vinter@imperial.ac.uk

2015-04-15

Sensitivity relations in optimal control provide an interpretation of the costate trajectory and the Hamiltonian, evaluated along an optimal trajectory, in terms of gradients of the value function. While sensitivity relations are a straightforward consequence of standard transversality conditions for state constraint free optimal control problems formulated in terms of control-dependent differential equations with smooth data, their verification for problems with either pathwise state constraints, nonsmooth data, or for problems where the dynamic constraint takes the form of a differential inclusion, requires careful analysis. In this paper we establish validity of both ‘full’ and ‘partial’ sensitivity relations for an adjointmore » state of the maximum principle, for optimal control problems with pathwise state constraints, where the underlying control system is described by a differential inclusion. The partial sensitivity relation interprets the costate in terms of partial Clarke subgradients of the value function with respect to the state variable, while the full sensitivity relation interprets the couple, comprising the costate and Hamiltonian, as the Clarke subgradient of the value function with respect to both time and state variables. These relations are distinct because, for nonsmooth data, the partial Clarke subdifferential does not coincide with the projection of the (full) Clarke subdifferential on the relevant coordinate space. We show for the first time (even for problems without state constraints) that a costate trajectory can be chosen to satisfy the partial and full sensitivity relations simultaneously. The partial sensitivity relation in this paper is new for state constraint problems, while the full sensitivity relation improves on earlier results in the literature (for optimal control problems formulated in terms of Lipschitz continuous multifunctions), because a less restrictive inward pointing hypothesis is invoked in the proof, and because it is validated for a stronger set of necessary conditions.« less

Instability of Bose-Einstein condensation into the one-particle ground state on quantum graphs under repulsive perturbations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bolte, Jens, E-mail: jens.bolte@rhul.ac.uk; Kerner, Joachim, E-mail: joachim.kerner@fernuni-hagen.de

In this paper we investigate Bose-Einstein condensation into the one-particle ground state in interacting quantum many-particle systems on graphs. We extend previous results obtained for particles on an interval and show that even arbitrarily small repulsive two-particle interactions destroy the condensate in the one-particle ground state present in the non-interacting Bose gas. Our results also cover singular two-particle interactions, such as the well-known Lieb-Liniger model, in the thermodynamic limit.

The Hyperfine Structure of the Ground State in the Muonic Helium Atoms

NASA Astrophysics Data System (ADS)

Aznabayev, D. T.; Bekbaev, A. K.; Korobov, V. I.

2018-05-01

Non-relativistic ionization energies 3He2+μ-e- and 4He2+μ-e- of helium-muonic atoms are calculated for ground states. The calculations are based on the variational method of the exponential expansion. Convergence of the variational energies is studied by an increasing of a number of the basis functions N. This allows to claim that the obtained energy values have 26 significant digits for ground states. With the obtained results we calculate hyperfine splitting of the muonic helium atoms.

14 CFR 151.61 - Grant payments: Partial.

Code of Federal Regulations, 2012 CFR

2012-01-01

... payments: Partial. (a) Subject to the final determination of allowable project costs as provided in § 151.63 partial grant payments for project costs may be made to a sponsor upon application. Unless... partial payments to the estimated United States share of the project costs of the airport development...

14 CFR 151.61 - Grant payments: Partial.

Code of Federal Regulations, 2010 CFR

2010-01-01

... payments: Partial. (a) Subject to the final determination of allowable project costs as provided in § 151.63 partial grant payments for project costs may be made to a sponsor upon application. Unless... partial payments to the estimated United States share of the project costs of the airport development...

14 CFR 151.61 - Grant payments: Partial.

Code of Federal Regulations, 2011 CFR

2011-01-01

... payments: Partial. (a) Subject to the final determination of allowable project costs as provided in § 151.63 partial grant payments for project costs may be made to a sponsor upon application. Unless... partial payments to the estimated United States share of the project costs of the airport development...

[Prevention of side effects and complications after operation for partial ileal bypass].

PubMed

Mirchuk, K K; Sedletskiĭ, Iu I

2014-01-01

Side effects and complications of the application of partial ileal bypass used for dislipidemia were analyzed in 162 patients with atherosclerosis. It was shown, that the partial ileal bypass operation could lead to the development of series of undesirable side effects such as diarrhea, hypovitaminosis B12, off-state intestine enteritis. The application of modification of partial ileal bypass such as formation of ileo-ileoanastomosis 5-6 cm long near ileocecal valve with the maintenance of its functions disposed the diarrhea and minimized the risk of the development of hypovitaminosis B12 after operation. It is possible to prevent the development of enteritis of off-state loop of the small intestine by using microanastomosis between off-state and functioning iliac intestine. The partial ileal bypass operation didn't influence on body weight, wouldn't increase the risk of stone formation in the gallbladder and kidneys. The risk of the development of hypovitaminosis B12 is minimal after operation.

Stretched proton-neutron configurations in fp-shell nuclei (II). Systematics

NASA Astrophysics Data System (ADS)

von Neumann-Cosel, P.; Fister, U.; Jahn, R.; Schenk, P.; Trelle, T. K.; Wenzel, D.; Wienands, U.

1994-03-01

The systematics of the binding energies of stretched proton-neutron configurations ( f{7}/{2}, g{9}/{2}) 8 -, ( p{3}/{2}, g{9}/{2}) 6 -, ( g{9}/{2}, p{3}/{2}) 6- and ( g{9}/{2}) 29 + are studied over a wide range of f p-shell nuclei. The effective proton-neutron interaction energies deduced from the data are nearly constant for ( p{3}/{2}, g{9}/{2}) 6 -and ( g{9}/{2}) 29 + states while the ( f{7}/{2}, g{9}/{2}) 8 - configuration reveals an additional repulsive term proportional to the partial filling of the f{7}/{2} orbit in the target ground state. Two-body matrix elements are extracted. A crude shell model, which predicts that the excitation energy of a stretched state is equal to the sum of the single-particle energies, works well for the 6 - and 9 + states, but fails for the 8 - levels due to neglect of the additional interactions described above. The physics underlying the empirically introduced basic assumptions of the crude shell model is discussed. The binding energies are found to be linearly dependent on the mass number A and the isospin Tz component and are well described by the weak-coupling model of Bansal and French. The derived parameters agree with averaged values of a similar analysis for the single-particle states in the corresponding odd-even neighbours. The data indicate a significant change of the particle-hole energies with closure of the proton f{7}/{2} shell.

Ground-based detections of sodium in HD 209458b's atmosphere in two data sets

NASA Astrophysics Data System (ADS)

Albrecht, S.; Snellen, I.; de Mooij, E.; Le Poole, R.

2009-02-01

We present two separate ground-based detections of sodium in the transmission spectrum of HD 209458b. First we reanalyzed an archival data set from the HDS spectrograph on Subaru, which shows sodium at a >5σ level. Secondly, our preliminary results of a UVES/VLT data set indicate sodium absorption at a similar level, although the data cover the eclipse only partially. Both results are fully consistent with the HST results of Charbonneau et al. (2002). The Na D absorption feature seems to be resolved in the narrowest passband.

Effect of replacing ground corn and soybean meal with licuri cake on the performance, digestibility, nitrogen metabolism and ingestive behavior in lactating dairy cows.

PubMed

Ferreira, A C; Vieira, J F; Barbosa, A M; Silva, T M; Bezerra, L R; Nascimento, N G; de Freitas, J E; Jaeger, S M P L; Oliveira, P de A; Oliveira, R L

2017-11-01

Licuri (Syagrus coronate) cake is a biodiesel by-product used in ruminant feed as a beneficial energy source for supplementation in managed pastures. The objective was to evaluate the performance, digestibility, nitrogen balance, blood metabolites, ingestive behavior and diet profitability of eight crossbred Holstein (3/4)×Gyr (5/8) multiparous cows (480±25 kg BW and 100 days milking) grazing and supplemented with licuri cake partially replacing ground corn and soybean meal in concentrate (0, 200, 400 and 600 g/kg in dry matter (DM)), distributed in an experimental duplicated 4×4 Latin square design. Licuri cake partially replacing ground corn and soybean meal increased (P<0.01) the intake and digestibility of ether extract and decreased the non-fiber carbohydrates; however, there were no influences on the intakes of DM, CP, NDF and total digestible nutrients (TDN). The digestibilities of DM, CP and NDF were not influenced by licuri cake addition. There was a decrease trend on TDN digestibility (P=0.08). Licuri cake replacing ground corn and soybean meal in concentrate did not affect the intake; fecal, urinary and mammary excretions; N balance; and triglycerides concentrations. However, the blood urea nitrogen (P=0.04) concentration decreased with the licuri cakes inclusion in cow supplementation. There was an increasing trend for serum creatinine (P=0.07). Licuri cake inclusion did not affect body condition score, production, yield, protein, lactose, total solids and solid non-fat contents of milk and Minas frescal cheese. There was a linear decrease in average daily weight gain (g/day). The milk fat concentration and cheese fat production (P<0.1) presented a linear increase with partial replacement of ground corn and soybean meal with licuri cakes. The addition of licuri cake did not alter the time spent feeding, ruminating or idling. There was an increasing trend in NDF feeding efficiency (P=0.09). The replacing of ground corn and soybean meal with licuri cake up to 600 g/kg decreased the concentrate cost by US$0.45/cow per day. Licuri cake replacing corn and soybeans (400 g/kg) in concentrate promoted a profit of US$0.07/animal per day. Licuri cake is indicated to concentrate the supplementation of dairy cows with average productions of 10 kg/day at levels up to 400 g/kg in the concentrate supplement because it provides an additional profit of US$0.07/animal per day and increased milk and Minas frescal cheese fat without negative effects on productive parameters.

E 2 / M 1 Mixing Ratios in Transitions From the Gamma-Vibrational-Bands to the Ground-State-Rotational-Bands of 102 , 104 , 106 , 108Mo, 108 , 110 , 112Ru, and 112 , 114 , 116Pd

NASA Astrophysics Data System (ADS)

Eldridge, Jonathan M.; Fenker, B.; Goodin, C.; Hamilton, J. H.; Wang, E. H.; Ramayya, A. V.; Daniel, A. V.; Ter-Akopian, G. M.; Luo, Y. X.; Rasmussen, J. O.; Oganesson, Yu. Ts.; Zhu, S. J.

2017-09-01

E 2 / M 1 mixing ratios have been measured for transitions from states in the γ-vibrational-bands (Iγ+) to states in the ground-state-bands (Ig+ or [I- 1 ] g +) of the neutron rich, deformed isotopes, 102 , 104 , 106 , 108Mo, 108 , 110 , 112Ru, and 112 , 114 , 116Pd, including from states as high as 9γ+. These measurements were done using the GAMMASPHERE detector array, which, at the time of the experiment, had 101 working HPGe detectors, arranged at 64 different angles. A 62 μCi source of 252Cf was placed inside GAMMASPHERE yielding 5.7 ×1011 γ - γ - γ and higher coincidence events. The angular correlation between the transitions from the γ-band to the ground band, and the pure E2 transitions within the ground band were then measured. These angular correlations yielded the mixing ratios, demonstrating that these transitions are all pure or nearly pure E2, in agreement with theory. In order to correct for possible attenuation due to the lifetime of the intermediate state in these correlations, the g-factors of the intermediate states needed to be known. Therefore, the g-factors of the 2g+ states in the ground state band have been measured. Supported by the US Department of Energy; Grant No. DE-FG0588ER40407, Contract No. DE-AC03-76SF00098.

Annual summary of ground-water conditions in Arizona, spring 1977 to spring 1978

USGS Publications Warehouse

,

1978-01-01

The withdrawal of ground water was about 5.5 million acre-feet in Arizona in 1977. About 4.7 million acre-feet of ground water was used for the irrigation of crops in 1977. The Salt River Valley and the lower Santa Cruz basin are the largest agricultural areas in the State. For 1973-77, ground-water withdrawal in the two areas was about 8.1 and 5.1 million acre-feet, respectively, and, in general, water levels are declining. Other areas in which ground-water withdrawals have caused water-level declines are the Willcox, San Simon, upper Santa Cruz, Avra Valley, Gila Bend, Harquahala Plains, and McMullen Valley areas. Two small-scale maps of Arizona show (1) pumpage of ground water by areas and (2) the status of the ground-water inventory in the State. The main map, scale 1:500 ,000, shows potential well production, depth to water in selected wells in spring 1978, and change in water level in selected wells from 1973 to 1978. The brief text that accompanies the maps summarizes the current ground-water conditions in the State. (Woodard-USGS)

A multireference perturbation method using non-orthogonal Hartree-Fock determinants for ground and excited states

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yost, Shane R.; Kowalczyk, Tim; Van Voorhis, Troy, E-mail: tvan@mit.edu

2013-11-07

In this article we propose the ΔSCF(2) framework, a multireference strategy based on second-order perturbation theory, for ground and excited electronic states. Unlike the complete active space family of methods, ΔSCF(2) employs a set of self-consistent Hartree-Fock determinants, also known as ΔSCF states. Each ΔSCF electronic state is modified by a first-order correction from Møller-Plesset perturbation theory and used to construct a Hamiltonian in a configuration interactions like framework. We present formulas for the resulting matrix elements between nonorthogonal states that scale as N{sub occ}{sup 2}N{sub virt}{sup 3}. Unlike most active space methods, ΔSCF(2) treats the ground and excited statemore » determinants even-handedly. We apply ΔSCF(2) to the H{sub 2}, hydrogen fluoride, and H{sub 4} systems and show that the method provides accurate descriptions of ground- and excited-state potential energy surfaces with no single active space containing more than 10 ΔSCF states.« less

FAST TRACK COMMUNICATION: Ground-state fidelity and entanglement entropy for the quantum three-state Potts model in one spatial dimension

NASA Astrophysics Data System (ADS)

Dai, Yan-Wei; Hu, Bing-Quan; Zhao, Jian-Hui; Zhou, Huan-Qiang

2010-09-01

The ground-state fidelity per lattice site is computed for the quantum three-state Potts model in a transverse magnetic field on an infinite-size lattice in one spatial dimension in terms of the infinite matrix product state algorithm. It is found that, on the one hand, a pinch point is identified on the fidelity surface around the critical point, and on the other hand, the ground-state fidelity per lattice site exhibits bifurcations at pseudo critical points for different values of the truncation dimension, which in turn approach the critical point as the truncation dimension becomes large. This implies that the ground-state fidelity per lattice site enables us to capture spontaneous symmetry breaking when the control parameter crosses the critical value. In addition, a finite-entanglement scaling of the von Neumann entropy is performed with respect to the truncation dimension, resulting in a precise determination of the central charge at the critical point. Finally, we compute the transverse magnetization, from which the critical exponent β is extracted from the numerical data.

Structures and Binding Energies of the Naphthalene Dimer in Its Ground and Excited States.

PubMed

Dubinets, N O; Safonov, A A; Bagaturyants, A A

2016-05-05

Possible structures of the naphthalene dimer corresponding to local energy minima in the ground and excited (excimer) electronic states are comprehensively investigated using DFT-D and TDDFT-D methods with a special accent on the excimer structures. The corresponding binding and electronic transition energies are calculated, and the nature of the electronic states in different structures is analyzed. Several parallel (stacked) and T-shaped structures were found in both the ground and excited (excimer) states in a rather narrow energy range. The T-shaped structure with the lowest energy in the excited state exhibits a marked charge transfer from the upright molecule to the base one.

A short note on ground-motion recordings from the M 7.9 Wenchuan, China, earthquake and ground-motion prediction equations in the Central and Eastern United States

USGS Publications Warehouse

Wang, Z.; Lu, M.

2011-01-01

The 12 May 2008 Wenchuan earthquake (M 7.9) occurred along the western edge of the eastern China SCR and was well recorded by modern strong-motion instruments: 93 strong-motion stations within 1.4 to 300 km rupture distance recorded the main event. Preliminary comparisons show some similarities between ground-motion attenuation in the Wenchuan region and the central and eastern United States, suggesting that ground motions from the Wenchuan earthquake could be used as a database providing constraints for developing GMPEs for large earthquakes in the central and eastern United States.

Ground state destabilization from a positioned general base in the ketosteroid isomerase active site.

PubMed

Ruben, Eliza A; Schwans, Jason P; Sonnett, Matthew; Natarajan, Aditya; Gonzalez, Ana; Tsai, Yingssu; Herschlag, Daniel

2013-02-12

We compared the binding affinities of ground state analogues for bacterial ketosteroid isomerase (KSI) with a wild-type anionic Asp general base and with uncharged Asn and Ala in the general base position to provide a measure of potential ground state destabilization that could arise from the close juxtaposition of the anionic Asp and hydrophobic steroid in the reaction's Michaelis complex. The analogue binding affinity increased ~1 order of magnitude for the Asp38Asn mutation and ~2 orders of magnitude for the Asp38Ala mutation, relative to the affinity with Asp38, for KSI from two sources. The increased level of binding suggests that the abutment of a charged general base and a hydrophobic steroid is modestly destabilizing, relative to a standard state in water, and that this destabilization is relieved in the transition state and intermediate in which the charge on the general base has been neutralized because of proton abstraction. Stronger binding also arose from mutation of Pro39, the residue adjacent to the Asp general base, consistent with an ability of the Asp general base to now reorient to avoid the destabilizing interaction. Consistent with this model, the Pro mutants reduced or eliminated the increased level of binding upon replacement of Asp38 with Asn or Ala. These results, supported by additional structural observations, suggest that ground state destabilization from the negatively charged Asp38 general base provides a modest contribution to KSI catalysis. They also provide a clear illustration of the well-recognized concept that enzymes evolve for catalytic function and not, in general, to maximize ground state binding. This ground state destabilization mechanism may be common to the many enzymes with anionic side chains that deprotonate carbon acids.

Interplay of spin-dependent delocalization and magnetic anisotropy in the ground and excited states of [Gd2@C78]- and [Gd2@C80]-

NASA Astrophysics Data System (ADS)

Mansikkamäki, Akseli; Popov, Alexey A.; Deng, Qingming; Iwahara, Naoya; Chibotaru, Liviu F.

2017-09-01

The magnetic properties and electronic structure of the ground and excited states of two recently characterized endohedral metallo-fullerenes, [Gd2@C78]- (1) and [Gd2@C80]- (2), have been studied by theoretical methods. The systems can be considered as [Gd2]5+ dimers encapsulated in a fullerene cage with the fifteen unpaired electrons ferromagnetically coupled into an S = 15/2 high-spin configuration in the ground state. The microscopic mechanisms governing the Gd-Gd interactions leading to the ferromagnetic ground state are examined by a combination of density functional and ab initio calculations and the full energy spectrum of the ground and lowest excited states is constructed by means of ab initio model Hamiltonians. The ground state is characterized by strong electron delocalization bordering on a σ type one-electron covalent bond and minor zero-field splitting (ZFS) that is successfully described as a second order spin-orbit coupling effect. We have shown that the observed ferromagnetic interaction originates from Hund's rule coupling and not from the conventional double exchange mechanism. The calculated ZFS parameters of 1 and 2 in their optimized geometries are in qualitative agreement with experimental EPR results. The higher excited states display less electron delocalization, but at the same time they possess unquenched first-order angular momentum. This leads to strong spin-orbit coupling and highly anisotropic energy spectrum. The analysis of the excited states presented here constitutes the first detailed study of the effects of spin-dependent delocalization in the presence of first order orbital angular momentum and the obtained results can be applied to other mixed valence lanthanide systems.

Partial gravity simulation using a pneumatic actuator with closed loop mechanical amplification

NASA Technical Reports Server (NTRS)

Ray, David M.

1994-01-01

To support future manned missions to the surface of the Moon and Mars or missions requiring manipulation of payloads and locomotion in space, a training device is required to simulate the conditions of both partial and microgravity as compared to the gravity on Earth. The focus of this paper is to present the development, construction, and testing of a partial gravity simulator which uses a pneumatic actuator with closed loop mechanical amplification. Results of the testing show that this type of simulator maintains a constant partial gravity simulation with a variation of the simulated body force between 2.2 percent and 10 percent, depending on the type of locomotion inputs. The data collected using the simulator show that mean stride frequencies at running speeds at lunar and Martian gravity levels are 12 percent less than those at Earth gravity. The data also show that foot/ground reaction forces at lunar and Martian gravity are, respectively, 62 percent and 51 percent less than those on Earth.

Arsenic in ground water of the United States: occurrence and geochemistry

USGS Publications Warehouse

Welch, Alan H.; Westjohn, D.B.; Helsel, Dennis R.; Wanty, Richard B.

2000-01-01

Concentrations of naturally occurring arsenic in ground water vary regionally due to a combination of climate and geology. Although slightly less than half of 30,000 arsenic analyses of ground water in the United States were 1 μg/L, about 10% exceeded 10 μg/L. At a broad regional scale, arsenic concentrations exceeding 10 μg/L appear to be more frequently observed in the western United States than in the eastern half. Arsenic concentrations in ground water of the Appalachian Highlands and the Atlantic Plain generally are very low ( 1 μg/L). Concentrations are somewhat greater in the Interior Plains and the Rocky Mountain System. Investigations of ground water in New England, Michigan, Minnesota, South Dakota, Oklahoma, and Wisconsin within the last decade suggest that arsenic concentrations exceeding 10 μg/L are more widespread and common than previously recognized.Arsenic release from iron oxide appears to be the most common cause of widespread arsenic concentrations exceeding 10 μg/L in ground water. This can occur in response to different geochemical conditions, including release of arsenic to ground water through reaction of iron oxide with either natural or anthropogenic (i.e., petroleum products) organic carbon. Iron oxide also can release arsenic to alkaline ground water, such as that found in some felsic volcanic rocks and alkaline aquifers of the western United States. Sulfide minerals are both a source and sink for arsenic. Geothermal water and high evaporation rates also are associated with arsenic concentrations 10g/L in ground and surface water, particularly in the west.Arsenic release from iron oxide appears to be the most common cause of widespread arsenic concentrations exceeding 10 µg/L a ground water. This can occur in response to different geochemical conditions, including release of arsenic to ground water through reaction of iron oxide with either natural or anthropogenic (i.e., petroleum products) organic carbon. Iron oxide also can release arsenic to alkaline ground water, such as that found in some felsic volcanic rocks and alkaline aquifers of the Western United States. Sulfide minerals are both a source and sink for arsenic. Geothermal water and high evaporation rates also are associated with arsenic concentrations ≥ 10g/L in ground and surface water, particularly in the west.

Crystal structure of Halobacterium salinarum halorhodopsin with a partially depopulated primary chloride-binding site.

PubMed

Schreiner, Madeleine; Schlesinger, Ramona; Heberle, Joachim; Niemann, Hartmut H

2016-09-01

The transmembrane pump halorhodopsin in halophilic archaea translocates chloride ions from the extracellular to the cytoplasmic side upon illumination. In the ground state a tightly bound chloride ion occupies the primary chloride-binding site (CBS I) close to the protonated Schiff base that links the retinal chromophore to the protein. The light-triggered trans-cis isomerization of retinal causes structural changes in the protein associated with movement of the chloride ion. In reverse, chemical depletion of CBS I in Natronomonas pharaonis halorhodopsin (NpHR) through deprotonation of the Schiff base results in conformational changes of the protein: a state thought to mimic late stages of the photocycle. Here, crystals of Halobacterium salinarum halorhodopsin (HsHR) were soaked at high pH to provoke deprotonation of the Schiff base and loss of chloride. The crystals changed colour from purple to yellow and the occupancy of CBS I was reduced from 1 to about 0.5. In contrast to NpHR, this chloride depletion did not cause substantial conformational changes in the protein. Nevertheless, two observations indicate that chloride depletion could eventually result in structural changes similar to those found in NpHR. Firstly, the partially chloride-depleted form of HsHR has increased normalized B factors in the region of helix C that is close to CBS I and changes its conformation in NpHR. Secondly, prolonged soaking of HsHR crystals at high pH resulted in loss of diffraction. In conclusion, the conformation of the chloride-free protein may not be compatible with this crystal form of HsHR despite a packing arrangement that hardly restrains helices E and F that presumably move during ion transport.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chou, Chia-Chun, E-mail: ccchou@mx.nthu.edu.tw

The Schrödinger–Langevin equation with linear dissipation is integrated by propagating an ensemble of Bohmian trajectories for the ground state of quantum systems. Substituting the wave function expressed in terms of the complex action into the Schrödinger–Langevin equation yields the complex quantum Hamilton–Jacobi equation with linear dissipation. We transform this equation into the arbitrary Lagrangian–Eulerian version with the grid velocity matching the flow velocity of the probability fluid. The resulting equation is simultaneously integrated with the trajectory guidance equation. Then, the computational method is applied to the harmonic oscillator, the double well potential, and the ground vibrational state of methyl iodide.more » The excellent agreement between the computational and the exact results for the ground state energies and wave functions shows that this study provides a synthetic trajectory approach to the ground state of quantum systems.« less

Quantum and isotope effects in lithium metal

NASA Astrophysics Data System (ADS)

Ackland, Graeme J.; Dunuwille, Mihindra; Martinez-Canales, Miguel; Loa, Ingo; Zhang, Rong; Sinogeikin, Stanislav; Cai, Weizhao; Deemyad, Shanti

2017-06-01

The crystal structure of elements at zero pressure and temperature is the most fundamental information in condensed matter physics. For decades it has been believed that lithium, the simplest metallic element, has a complicated ground-state crystal structure. Using synchrotron x-ray diffraction in diamond anvil cells and multiscale simulations with density functional theory and molecular dynamics, we show that the previously accepted martensitic ground state is metastable. The actual ground state is face-centered cubic (fcc). We find that isotopes of lithium, under similar thermal paths, exhibit a considerable difference in martensitic transition temperature. Lithium exhibits nuclear quantum mechanical effects, serving as a metallic intermediate between helium, with its quantum effect-dominated structures, and the higher-mass elements. By disentangling the quantum kinetic complexities, we prove that fcc lithium is the ground state, and we synthesize it by decompression.

Ground state energy of electrons in a static point-ion lattice

NASA Technical Reports Server (NTRS)

Styer, D. F.; Ashcroft, N. W.

1983-01-01

The ground state energy of a neutral collection of protons and electrons was investigated under the assumption that in the ground state configuration, static protons occupy the sites of a rigid Bravais lattice. The Wigner-Seitz method was used in conjunction with three postulated potentials: bare Coulomb, Thomas-Fermi screening, and screening by a uniform bare background charge. Within these approximations, the exact band-minimum energy and wave functions are derived. For each of the three potentials, the approximate minimum ground state energy per proton (relative to isolated electrons and protons) is, respectively, -1.078 Ry, -1.038 Ry, and -1.052 Ry. These three minima all fall at a density of about 0.60 gm/cu cm, which is thus an approximate lower bound on the density of metallic hydrogen at its transition pressure.

Universality of entropy scaling in one dimensional gapless models.

PubMed

Korepin, V E

2004-03-05

We consider critical models in one dimension. We study the ground state in the thermodynamic limit (infinite lattice). We are interested in an entropy of a subsystem. We calculate the entropy of a part of the ground state from a space interval (0,x). At zero temperature it describes the entanglement of the part of the ground state from this interval with the rest of the ground state. We obtain an explicit formula for the entropy of the subsystem at any temperature. At zero temperature our formula reproduces a logarithmic formula, discovered by Vidal, Latorre, Rico, and Kitaev for spin chains. We prove our formula by means of conformal field theory and the second law of thermodynamics. Our formula is universal. We illustrate it for a Bose gas with a delta interaction and for the Hubbard model.

Measurements of copper ground-state and metastable level population densities in a copper-chloride laser

NASA Technical Reports Server (NTRS)

Nerheim, N. M.

1977-01-01

The population densities of both the ground and the 2D(5/2) metastable states of copper atoms in a double-pulsed copper-chloride laser are correlated with laser energy as a function of time after the dissociation current pulse. Time-resolved density variations of the ground and excited copper atoms were derived from measurements of optical absorption at 324.7 and 510.6 nm, respectively, over a wide range of operating conditions in laser tubes with diameters of 4 to 40 mm. The minimum delay between the two current pulses at which lasing was observed is shown to be a function of the initial density and subsequent decay of the metastable state. Similarly, the maximum delay is shown to be a function of the initial density and decay of the ground state.

On the ground-state degeneracy and entropy in a double-tetrahedral chain formed by the localized Ising spins and mobile electrons

NASA Astrophysics Data System (ADS)

Gálisová, Lucia

2018-05-01

Ground-state properties of a hybrid double-tetrahedral chain, in which the localized Ising spins regularly alternate with triangular plaquettes occupied by a variable number of mobile electrons, are exactly investigated. We demonstrate that the zero-temperature phase diagram of the model involves several non-degenerate, two-fold degenerate and macroscopically degenerate chiral phases. Low-temperature dependencies of the entropy and specific heat are also examined in order to gain a deeper insight into the degeneracy of individual ground-state phases and phase transitions. It is shown that a diversity of the ground-state degeneracy manifests itself in multiple-peak structures of both thermodynamic quantities. A remarkable temperature dependencies of the specific heat with two and three Schottky-type maxima are discussed in detail.

Diffusion and reactivity of ground-state nitrogen atoms N(4S) between 3 and 15 K: application to the hydrogen abstraction reaction from methane under non-energetic conditions

NASA Astrophysics Data System (ADS)

Nourry, Sendres; Krim, Lahouari

2015-07-01

We have characterized the CH4 + N(4S) reaction in solid phase, at very low temperature, under non-energetic conditions and where the CH4 and N reactants are in their ground states. A microwave-driven atomic source has been used to generate ground-state nitrogen atoms N(4S), and experiments have been carried out at temperatures as low as 3 K to reduce the mobility of the trapped species in solid phase and hence to freeze the first step of the CH4 + N reaction pathway. Leaving the formed solid sample in the dark for a while allows all trapped reactants to relax to the ground state, specifically radicals and excited species streaming from the plasma discharge. Such a method could be the only possibility of proving that the CH4 + N reaction occurs between CH4 and N reactants in their ground states without any additional energy to initiate the chemical process. The appearance of the CH3 reaction product, just by inducing the mobility of N atoms between 3 and 11 K, translates that a hydrogen abstraction reaction from methane, under non-energetic conditions, will start occurring at very low temperature. The formation of methyl radical, under these experimental conditions, is due to recombination processes N(4S)-N(4S) of ground-state nitrogen atoms without any contribution of cosmic ray particles or high-energy photons.

Incorporating Conservation Zone Effectiveness for Protecting Biodiversity in Marine Planning

PubMed Central

Makino, Azusa; Klein, Carissa J.; Beger, Maria; Jupiter, Stacy D.; Possingham, Hugh P.

2013-01-01

Establishing different types of conservation zones is becoming commonplace. However, spatial prioritization methods that can accommodate multiple zones are poorly understood in theory and application. It is typically assumed that management regulations across zones have differential levels of effectiveness (“zone effectiveness”) for biodiversity protection, but the influence of zone effectiveness on achieving conservation targets has not yet been explored. Here, we consider the zone effectiveness of three zones: permanent closure, partial protection, and open, for planning for the protection of five different marine habitats in the Vatu-i-Ra Seascape, Fiji. We explore the impact of differential zone effectiveness on the location and costs of conservation priorities. We assume that permanent closure zones are fully effective at protecting all habitats, open zones do not contribute towards the conservation targets and partial protection zones lie between these two extremes. We use four different estimates for zone effectiveness and three different estimates for zone cost of the partial protection zone. To enhance the practical utility of the approach, we also explore how much of each traditional fishing ground can remain open for fishing while still achieving conservation targets. Our results show that all of the high priority areas for permanent closure zones would not be a high priority when the zone effectiveness of the partial protection zone is equal to that of permanent closure zones. When differential zone effectiveness and costs are considered, the resulting marine protected area network consequently increases in size, with more area allocated to permanent closure zones to meet conservation targets. By distributing the loss of fishing opportunity equitably among local communities, we find that 84–88% of each traditional fishing ground can be left open while still meeting conservation targets. Finally, we summarize the steps for developing marine zoning that accounts for zone effectiveness. PMID:24223870

Sonic Boom Pressure Signature Uncertainty Calculation and Propagation to Ground Noise

NASA Technical Reports Server (NTRS)

West, Thomas K., IV; Bretl, Katherine N.; Walker, Eric L.; Pinier, Jeremy T.

2015-01-01

The objective of this study was to outline an approach for the quantification of uncertainty in sonic boom measurements and to investigate the effect of various near-field uncertainty representation approaches on ground noise predictions. These approaches included a symmetric versus asymmetric uncertainty band representation and a dispersion technique based on a partial sum Fourier series that allows for the inclusion of random error sources in the uncertainty. The near-field uncertainty was propagated to the ground level, along with additional uncertainty in the propagation modeling. Estimates of perceived loudness were obtained for the various types of uncertainty representation in the near-field. Analyses were performed on three configurations of interest to the sonic boom community: the SEEB-ALR, the 69o DeltaWing, and the LM 1021-01. Results showed that representation of the near-field uncertainty plays a key role in ground noise predictions. Using a Fourier series based dispersion approach can double the amount of uncertainty in the ground noise compared to a pure bias representation. Compared to previous computational fluid dynamics results, uncertainty in ground noise predictions were greater when considering the near-field experimental uncertainty.

Annual summary of ground-water conditions in Arizona, Spring 1981 to Spring 1982

USGS Publications Warehouse

,

1982-01-01

The withdrawal of ground water was about 5.4 million acre-feet in Arizona in 1981, which is about 800,000 acre-feet more than the amount withdrawn in 1980. Most of the increase in 1981 was in the amount of ground water used for irrigation in the Basin and Range lowlands province. Through 1981, slightly more than 189 million acre-feet of ground water had been withdrawn from the ground-water reservoirs in Arizona. The report contains two small-scale maps that show ground-water pumpage by areas and the status of the ground-water inventory in the State. The main map, which is at a scale of 1:500,000, shows potential well production, depth to water in selected wells in spring 1982, and change in water level in selected wells from 1977 to 1982. A brief text summarizes the current ground-water conditions in the State. (USGS)

Reactive ground-state pathways are not ubiquitous in red/green cyanobacteriochromes.

PubMed

Chang, Che-Wei; Gottlieb, Sean M; Kim, Peter W; Rockwell, Nathan C; Lagarias, J Clark; Larsen, Delmar S

2013-09-26

Recent characterization of the red/green cyanobacteriochrome (CBCR) NpR6012g4 revealed a high quantum yield for its forward photoreaction [J. Am. Chem. Soc. 2012, 134, 130-133] that was ascribed to the activity of hidden, productive ground-state intermediates. The dynamics of the pathways involving these ground-state intermediates was resolved with femtosecond dispersed pump-dump-probe spectroscopy, the first such study reported for any CBCR. To address the ubiquity of such second-chance initiation dynamics (SCID) in CBCRs, we examined the closely related red/green CBCR NpF2164g6 from Nostoc punctiforme. Both NpF2164g6 and NpR6012g4 use phycocyanobilin as the chromophore precursor and exhibit similar excited-state dynamics. However, NpF2164g6 exhibits a lower quantum yield of 32% for the generation of the isomerized Lumi-R primary photoproduct, compared to 40% for NpR6012g4. This difference arises from significantly different ground-state dynamics between the two proteins, with the SCID mechanism deactivated in NpF2164g6. We present an integrated inhomogeneous target model that self-consistently fits the pump-probe and pump-dump-probe signals for both forward and reverse photoreactions in both proteins. This work demonstrates that reactive ground-state intermediates are not ubiquitous phenomena in CBCRs.

Quenched crystal-field disorder and magnetic liquid ground states in Tb 2 Sn 2 - x Ti x O 7 [Crystal field disorder in the quantum spin ice ground state of Tb2Sn2-xTixO7

DOE PAGES

Gaulin, B. D.; Kermarrec, E.; Dahlberg, M. L.; ...

2015-06-01

Solid-solutions of the "soft" quantum spin ice pyrochlore magnets Tb 2B 2O 7 with B=Ti and Sn display a novel magnetic ground state in the presence of strong B-site disorder, characterized by a low susceptibility and strong spin fluctuations to temperatures below 0.1 K. These materials have been studied using ac-susceptibility and muSR techniques to very low temperatures, and time-of-flight inelastic neutron scattering techniques to 1.5 K. Remarkably, neutron spectroscopy of the Tb 3+ crystal field levels appropriate to at high B-site mixing (0.5 < x < 1.5 in Tb 2Sn 2-xTi xO 7) reveal that the doublet ground andmore » first excited states present as continua in energy, while transitions to singlet excited states at higher energies simply interpolate between those of the end members of the solid solution. The resulting ground state suggests an extreme version of a random-anisotropy magnet, with many local moments and anisotropies, depending on the precise local configuration of the six B sites neighboring each magnetic Tb 3+ ion.« less

Theoretical Interpretation of the Fluorescence Spectra of Toluene and P- Cresol

DTIC Science & Technology

1994-07-01

NUMBER OF PAGES Toluene Geometrica 25 p-Cresol Fluorescence Is. PRICE CODE Spectra 17. SECURITY CLASSIFICATION 13. SECURITY CLASSIFICATION 19...State Frequencies of Toluene ................ 19 6 Computed and exp" Ground State Frequencies of p-Cresol ............... 20 7 Correction Factors for...Computed Ground State Vibrational Frequencies ....... 21 8 Computed and Corrected Excited State Frequencies of Toluene ............. 22 9 Computed and

Determination and Comparison of Carbonyl Stretching Frequency of a Ketone in Its Ground State and the First Electronic Excited State

ERIC Educational Resources Information Center

Bandyopadhyay, Subhajit; Roy, Saswata

2014-01-01

This paper describes an inexpensive experiment to determine the carbonyl stretching frequency of an organic keto compound in its ground state and first electronic excited state. The experiment is simple to execute, clarifies some of the fundamental concepts of spectroscopy, and is appropriate for a basic spectroscopy laboratory course. The…

Entanglement entropy from tensor network states for stabilizer codes

NASA Astrophysics Data System (ADS)

He, Huan; Zheng, Yunqin; Bernevig, B. Andrei; Regnault, Nicolas

2018-03-01

In this paper, we present the construction of tensor network states (TNS) for some of the degenerate ground states of three-dimensional (3D) stabilizer codes. We then use the TNS formalism to obtain the entanglement spectrum and entropy of these ground states for some special cuts. In particular, we work out examples of the 3D toric code, the X-cube model, and the Haah code. The latter two models belong to the category of "fracton" models proposed recently, while the first one belongs to the conventional topological phases. We mention the cases for which the entanglement entropy and spectrum can be calculated exactly: For these, the constructed TNS is a singular value decomposition (SVD) of the ground states with respect to particular entanglement cuts. Apart from the area law, the entanglement entropies also have constant and linear corrections for the fracton models, while the entanglement entropies for the toric code models only have constant corrections. For the cuts we consider, the entanglement spectra of these three models are completely flat. We also conjecture that the negative linear correction to the area law is a signature of extensive ground-state degeneracy. Moreover, the transfer matrices of these TNSs can be constructed. We show that the transfer matrices are projectors whose eigenvalues are either 1 or 0. The number of nonzero eigenvalues is tightly related to the ground-state degeneracy.

On the formation of anions: frequency-, angle-, and time-resolved photoelectron imaging of the menadione radical anion† †Electronic supplementary information (ESI) available: A summary of the ground-state geometries and molecular orbitals from the ab initio calculations; fitted residuals from the FA-PI simulation; plots of all spectra included in the frequency-resolved two-dimensional figure; and example time-resolved PE spectra from the 3.10 + 1.55 eV pump-probe experiments. See DOI: 10.1039/c4sc03491k Click here for additional data file.

PubMed Central

Bull, James N.; West, Christopher W.

2015-01-01

Frequency-, angle-, and time-resolved photoelectron imaging of gas-phase menadione (vitamin K3) radical anions was used to show that quasi-bound resonances of the anion can act as efficient doorway states to produce metastable ground electronic state anions on a sub-picosecond timescale. Several anion resonances have been experimentally observed and identified with the assistance of ab initio calculations, and ground state anion recovery was observed across the first 3 eV above threshold. Time-resolved measurements revealed the mechanism of electronic ground state anion formation, which first involves a cascade of very fast internal conversion processes to a bound electronic state that, in turn, decays by slower internal conversion to the ground state. Autodetachment processes from populated resonances are inefficient compared with electronic relaxation through internal conversion. The mechanistic understanding gained provides insight into the formation of radical anions in biological and astrochemical systems. PMID:29560245