Exposure to sublethal concentrations of copper changes biochemistry parameters in silver catfish, Rhamdia quelen, Quoy & Gaimard.

PubMed

Pretto, Alexandra; Loro, Vania Lucia; Silva, Vera M Machado; Salbego, Joseânia; de Menezes, Charlene Cavalheiro; Souza, Carine de Freitas; Gioda, Carolina Rosa; Baldisserotto, Bernardo

2014-04-01

The effects of Cu exposure on catalase (CAT) and acetylcholinesterase (AChE) activity, formation of thiobarbituric acid-reactive species (TBARS) and metabolic parameters were evaluated in silver catfish (Rhamdia quelen). The fish were exposed for 45 days to 0, 16 and 29 μg/L Cu. The fish that were exposed to Cu exhibited lower TBARS levels in the muscle and higher TBARS levels in the liver. They also showed lower CAT activity in the liver and lower AChE activity in the brain and muscle. Higher glucose and lactate and lower protein plasma levels were observed in the fish exposed to Cu. The changes in the hepatic metabolic parameters were Cu concentration dependent. In the muscle, lower glycogen and higher lactate levels were observed in the fish exposed to Cu. Alterations in the metabolic parameters showed a preference for the anaerobic pathway of energy production and liver protein catabolism to supply the energy demand.

A systemic approach to explore the flexibility of energy stores at the cellular scale: Examples from muscle cells.

PubMed

Taghipoor, Masoomeh; van Milgen, Jaap; Gondret, Florence

2016-09-07

Variations in energy storage and expenditure are key elements for animals adaptation to rapidly changing environments. Because of the multiplicity of metabolic pathways, metabolic crossroads and interactions between anabolic and catabolic processes within and between different cells, the flexibility of energy stores in animal cells is difficult to describe by simple verbal, textual or graphic terms. We propose a mathematical model to study the influence of internal and external challenges on the dynamic behavior of energy stores and its consequence on cell energy status. The role of the flexibility of energy stores on the energy equilibrium at the cellular level is illustrated through three case studies: variation in eating frequency (i.e., glucose input), level of physical activity (i.e., ATP requirement), and changes in cell characteristics (i.e., maximum capacity of glycogen storage). Sensitivity analysis has been performed to highlight the most relevant parameters of the model; model simulations have then been performed to illustrate how variation in these key parameters affects cellular energy balance. According to this analysis, glycogen maximum accumulation capacity and homeostatic energy demand are among the most important parameters regulating muscle cell metabolism to ensure its energy equilibrium. Copyright © 2016 Elsevier Ltd. All rights reserved.

Modeling and optimization of actively Q-switched Nd-doped quasi-three-level laser

NASA Astrophysics Data System (ADS)

Yan, Renpeng; Yu, Xin; Li, Xudong; Chen, Deying; Gao, Jing

2013-09-01

The energy transfer upconversion and the ground state absorption are considered in solving the rate equations for an active Q-switched quasi-three-level laser. The dependence of output pulse characters on the laser parameters is investigated by solving the rate equations. The influence of the energy transfer upconversion on the pulsed laser performance is illustrated and discussed. By this model, the optimal parameters could be achieved for arbitrary quasi-three-level Q-switched lasers. An acousto-optical Q-switched Nd:YAG 946 nm laser is constructed and the reliability of the theoretical model is demonstrated.

Spectrum and Energy Levels of Five-Times Ionized Zirconium (Zr VI)

PubMed Central

Lindsay, Mark D.

2016-01-01

We carried out a new analysis of the spectrum of five-times-ionized zirconium Zr VI. For this we used sliding-spark discharges together with normal- and grazing-incidence spectrographs to observe the spectrum from 160 to 2000 Å. These observations showed that the analysis of this spectrum by Khan Z. A. et al. 1985 Phys. Scr. 31 837 contained a significant number of incorrect energy levels. We have now classified ∼420 lines as transitions between 23 even-parity levels 73 odd-parity levels. The 4s24p5, 4s4p6, 4s24p44d, 5s, 5d, 6s configurations are now complete, although a few levels of 4s24p45d are tentative. We determined Ritz-type wavelengths for ∼135 lines from the optimized energy levels. The uncertainties range from 0.0003 to 0.0020 Å. Hartree-Fock calculations and least-squares fits of the energy parameters to the observed levels were used to interpret the observed configurations. Oscillator strengths for all classified lines were calculated with the fitted parameters. The results are compared with values for the level energies, percentage compositions, and transition probabilities from recent ab initio theoretical calculations. The ionization energy was revised to 777380±300 cm-1 (96.38±0.04 eV). PMID:27325903

Spectrum and Energy Levels of Five-Times Ionized Zirconium (Zr VI).

PubMed

Reader, Joseph; Lindsay, Mark D

2016-02-01

We carried out a new analysis of the spectrum of five-times-ionized zirconium Zr VI. For this we used sliding-spark discharges together with normal- and grazing-incidence spectrographs to observe the spectrum from 160 to 2000 Å. These observations showed that the analysis of this spectrum by Khan Z. A. et al. 1985 Phys. Scr. 31 837 contained a significant number of incorrect energy levels. We have now classified ∼420 lines as transitions between 23 even-parity levels 73 odd-parity levels. The 4s 2 4p 5 , 4s4p 6 , 4s 2 4p 4 4d, 5s, 5d, 6s configurations are now complete, although a few levels of 4s 2 4p 4 5d are tentative. We determined Ritz-type wavelengths for ∼135 lines from the optimized energy levels. The uncertainties range from 0.0003 to 0.0020 Å. Hartree-Fock calculations and least-squares fits of the energy parameters to the observed levels were used to interpret the observed configurations. Oscillator strengths for all classified lines were calculated with the fitted parameters. The results are compared with values for the level energies, percentage compositions, and transition probabilities from recent ab initio theoretical calculations. The ionization energy was revised to 777380±300 cm -1 (96.38±0.04 eV).

Spectrum and energy levels of five-times ionized zirconium (Zr VI)

NASA Astrophysics Data System (ADS)

Reader, Joseph; Lindsay, Mark D.

2016-02-01

We carried out a new analysis of the spectrum of five-times-ionized zirconium Zr VI. For this we used sliding-spark discharges together with normal- and grazing-incidence spectrographs to observe the spectrum from 160 to 2000 Å. These observations showed that the analysis of this spectrum by Khan et al (1985 Phys. Scr. 31 837) contained a significant number of incorrect energy levels. We have now classified ˜420 lines as transitions between 23 even-parity levels 73 odd-parity levels. The 4s24p5, 4s4p6, 4s24p44d, 5s, 5d, 6s configurations are now complete, although a few levels of 4s24p45d are tentative. We determined Ritz-type wavelengths for ˜135 lines from the optimized energy levels. The uncertainties range from 0.0003 to 0.0020 Å. Hartree-Fock calculations and least-squares fits of the energy parameters to the observed levels were used to interpret the observed configurations. Oscillator strengths for all classified lines were calculated with the fitted parameters. The results are compared with values for the level energies, percentage compositions, and transition probabilities from recent ab initio theoretical calculations. The ionization energy was revised to 777 380 ± 300 cm-1 (96.38 ± 0.04 eV).

Design and Implementation of RF Energy Harvesting System for Low-Power Electronic Devices

NASA Astrophysics Data System (ADS)

Uzun, Yunus

2016-08-01

Radio frequency (RF) energy harvester systems are a good alternative for energizing of low-power electronics devices. In this work, an RF energy harvester is presented to obtain energy from Global System for Mobile Communications (GSM) 900 MHz signals. The energy harvester, consisting of a two-stage Dickson voltage multiplier circuit and L-type impedance matching circuits, was designed, simulated, fabricated and tested experimentally in terms of its performance. Simulation and experimental works were carried out for various input power levels, load resistances and input frequencies. Both simulation and experimental works have been carried out for this frequency band. An efficiency of 45% is obtained from the system at 0 dBm input power level using the impedance matching circuit. This corresponds to the power of 450 μW and this value is sufficient for many low-power devices. The most important parameters affecting the efficiency of the RF energy harvester are the input power level, frequency band, impedance matching and voltage multiplier circuits, load resistance and the selection of diodes. RF energy harvester designs should be optimized in terms of these parameters.

Optimization of CW Fiber Lasers With Strong Nonlinear Cavity Dynamics

NASA Astrophysics Data System (ADS)

Shtyrina, O. V.; Efremov, S. A.; Yarutkina, I. A.; Skidin, A. S.; Fedoruk, M. P.

2018-04-01

In present work the equation for the saturated gain is derived from one-level gain equations describing the energy evolution inside the laser cavity. It is shown how to derive the parameters of the mathematical model from the experimental results. The numerically-estimated energy and spectrum of the signal are in good agreement with the experiment. Also, the optimization of the output energy is performed for a given set of model parameters.

The need for control of magnetic parameters for energy efficient performance of magnetic tunnel junctions

NASA Astrophysics Data System (ADS)

Farhat, I. A. H.; Gale, E.; Alpha, C.; Isakovic, A. F.

2017-07-01

Optimizing energy performance of Magnetic Tunnel Junctions (MTJs) is the key for embedding Spin Transfer Torque-Random Access Memory (STT-RAM) in low power circuits. Due to the complex interdependencies of the parameters and variables of the device operating energy, it is important to analyse parameters with most effective control of MTJ power. The impact of threshold current density, Jco , on the energy and the impact of HK on Jco are studied analytically, following the expressions that stem from Landau-Lifshitz-Gilbert-Slonczewski (LLGS-STT) model. In addition, the impact of other magnetic material parameters, such as Ms , and geometric parameters such as tfree and λ is discussed. Device modelling study was conducted to analyse the impact at the circuit level. Nano-magnetism simulation based on NMAGTM package was conducted to analyse the impact of controlling HK on the switching dynamics of the film.

Design parameters of a miniaturized piezoelectric underwater acoustic transmitter.

PubMed

Li, Huidong; Deng, Zhiqun Daniel; Yuan, Yong; Carlson, Thomas J

2012-01-01

PZT ceramics have been widely used in underwater acoustic transducers. However, literature available discussing the design parameters of a miniaturized PZT-based low-duty-cycle transmitter is very limited. This paper discusses some of the design parameters--the backing material, driving voltage, PZT material type, power consumption and the transducer length of a miniaturized acoustic fish tag using a PZT tube. Four different types of PZT were evaluated with respect to the source level, energy consumption and bandwidth of the transducer. The effect of the tube length on the source level is discussed. The results demonstrate that ultralow-density closed-cell foam is the best backing material for the PZT tube. The Navy Type VI PZTs provide the best source level with relatively low energy consumption and that a low transducer capacitance is preferred for high efficiency. A 35% reduction in the transducer length results in 2 dB decrease in source level.

Minimizing energy dissipation of matrix multiplication kernel on Virtex-II

NASA Astrophysics Data System (ADS)

Choi, Seonil; Prasanna, Viktor K.; Jang, Ju-wook

2002-07-01

In this paper, we develop energy-efficient designs for matrix multiplication on FPGAs. To analyze the energy dissipation, we develop a high-level model using domain-specific modeling techniques. In this model, we identify architecture parameters that significantly affect the total energy (system-wide energy) dissipation. Then, we explore design trade-offs by varying these parameters to minimize the system-wide energy. For matrix multiplication, we consider a uniprocessor architecture and a linear array architecture to develop energy-efficient designs. For the uniprocessor architecture, the cache size is a parameter that affects the I/O complexity and the system-wide energy. For the linear array architecture, the amount of storage per processing element is a parameter affecting the system-wide energy. By using maximum amount of storage per processing element and minimum number of multipliers, we obtain a design that minimizes the system-wide energy. We develop several energy-efficient designs for matrix multiplication. For example, for 6×6 matrix multiplication, energy savings of upto 52% for the uniprocessor architecture and 36% for the linear arrary architecture is achieved over an optimized library for Virtex-II FPGA from Xilinx.

Fission Dynamics with Microscopic Level Densities

DOE PAGES

Ward, D.; Carlsson, B. G.; Dossing, Th.; ...

2017-01-01

We present a consistent framework for treating the energy and angularmomentum dependence of the shape evolution in the nuclear fission. It combines microscopically calculated level densities with the Metropolis-walk method, has no new parameters, and can elucidate the energy-dependent influence of pairing and shell effects on the dynamics of warm nuclei.

Theoretical branching ratios for the 5I7 to 5I7 levels of Ho(3+) in the garnets A3B2C3O12 (A = Y,La,Lu,Gd; B = Al,Lu,Sc,Ga; C = Al,Ga)

NASA Technical Reports Server (NTRS)

Filer, Elizabeth D.; Morrison, Clyde A.; Turner, Gregory A.; Barnes, Norman P.

1991-01-01

Results are reported from an experimental study investigating triply ionized holmium in 10 garnets using the point-change model to predict theoretical energy levels and temperature-dependent branching ratios for the 5I7 to 5I8 manifolds for temperatures between 50 and 400 K. Plots were made for the largest lines at 300 K. YScAG was plotted twice, once for each set of X-ray data available. Energy levels are predicted based on theoretical crystal-field parameters, and good agreement to experiment is found. It is suggested that the present set of theoretical crystal-field parameters provides good estimates of the energy levels for the other hosts on which there are no experimental optical data. X-ray and index-of-refraction data are used to evaluate the performance of 10 lasers via a quantum mechanical model to predict the position of the energy levels and the temperature-dependent branching rations of the 5I7 to 5I8 levels of holmium. The fractional population inversion required for threshold is also evaluated.

Absorption Coefficient of Alkaline Earth Halides.

DTIC Science & Technology

1980-04-01

not observed at low energy level , are developed at high power levels . No matter how low the absorption is. the effect is objectionable at high-energy... levels . As a natural consequence, the magnitude of the absorption coefficient is the key parameter in selecting laser window materials. Over the past...Presence of impurities can complicate the exponential tail. particularly at low absorption levels . The impurities may enter 12 the lattice singly or

The Sixth Spectrum of Iridium (Ir VI): Determination of the 5d4, 5d36s and 5d36p Configurations

NASA Astrophysics Data System (ADS)

Azarov, V. I.; Gayasov, R. R.; Gayasov, R. R.; Joshi, Y. N.; Churilov, S. S.

The spectrum of five times ionized iridium, Ir VI, was investigated in the 420-1520 Å wavelength region. The analysis has led to the determination of the 5d4, 5d36s and 5d36p configurations. Thirty of thirty four theoretically possible 5d4 levels, 27 of 38 possible 5d36s levels and 96 of 110 possible 5d36p levels have been established. The levels are based on 711 classified spectral lines. The level structure of the configurations has been theoretically interpreted using the orthogonal operators technique. The energy parameters have been determined by a least squares fit to the observed levels. Calculated energy values and LS-compositions, obtained from the fitted parameter values are given.

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

Liu, Shengqiang; Li, Jie; Yu, Junsheng, E-mail: jsyu@uestc.edu.cn

A color tuning index (I{sub CT}) parameter for evaluating the color change capability of color-tunable organic light-emitting diodes (CT-OLEDs) was proposed and formulated. And a series of CT-OLEDs, consisting of five different carrier/exciton adjusting interlayers (C/EALs) inserted between two complementary emitting layers, were fabricated and applied to disclose the relationship between I{sub CT} and C/EALs. The result showed that the trend of electroluminescence spectra behavior in CT-OLEDs has good accordance with I{sub CT} values, indicating that the I{sub CT} parameter is feasible for the evaluation of color variation. Meanwhile, by changing energy level and C/EAL thickness, the optimized device withmore » the widest color tuning range was based on N,N′-dicarbazolyl-3,5-benzene C/EAL, exhibiting the highest I{sub CT} value of 41.2%. Based on carrier quadratic hopping theory and exciton transfer model, two fitting I{sub CT} formulas derived from the highest occupied molecular orbital (HOMO) energy level and triplet energy level were simulated. Finally, a color tuning prediction (CTP) model was developed to deduce the I{sub CT} via C/EAL HOMO and triplet energy levels, and verified by the fabricated OLEDs with five different C/EALs. We believe that the CTP model assisted with I{sub CT} parameter will be helpful for fabricating high performance CT-OLEDs with a broad range of color tuning.« less

Influence of primary fragment excitation energy and spin distributions on fission observables

NASA Astrophysics Data System (ADS)

Litaize, Olivier; Thulliez, Loïc; Serot, Olivier; Chebboubi, Abdelaziz; Tamagno, Pierre

2018-03-01

Fission observables in the case of 252Cf(sf) are investigated by exploring several models involved in the excitation energy sharing and spin-parity assignment between primary fission fragments. In a first step the parameters used in the FIFRELIN Monte Carlo code "reference route" are presented: two parameters for the mass dependent temperature ratio law and two constant spin cut-off parameters for light and heavy fragment groups respectively. These parameters determine the initial fragment entry zone in excitation energy and spin-parity (E*, Jπ). They are chosen to reproduce the light and heavy average prompt neutron multiplicities. When these target observables are achieved all other fission observables can be predicted. We show here the influence of input parameters on the saw-tooth curve and we discuss the influence of a mass and energy-dependent spin cut-off model on gamma-rays related fission observables. The part of the model involving level densities, neutron transmission coefficients or photon strength functions remains unchanged.

Influence of dense plasma on the energy levels and transition properties in highly charged ions

NASA Astrophysics Data System (ADS)

Chen, Zhan-Bin; Hu, Hong-Wei; Ma, Kun; Liu, Xiao-Bin; Guo, Xue-Ling; Li, Shuang; Zhu, Bo-Hong; Huang, Lian; Wang, Kai

2018-03-01

The studies of the influence of plasma environments on the level structures and transition properties for highly charged ions are presented. For the relativistic treatment, we implemented the multiconfiguration Dirac-Fock method incorporating the ion sphere (IS) model potential, in which the plasma screening is taken into account as a modified interaction potential between the electron and the nucleus. For the nonrelativistic treatment, analytical solutions of the Schrödinger equation with two types of the IS screened potential are proposed. The Ritz variation method is used with hydrogenic wave function as a trial wave function that contains two unknown variational parameters. Bound energies are derived from an energy equation, and the variational parameters are obtained from the minimisation condition of the expectation value of the energy. Numerical results for hydrogen-like ions in dense plasmas are presented as examples. A detailed analysis of the influence of relativistic effects on the energy levels and transition properties is also reported. Our results are compared with available results in the literature showing a good quantitative agreement.

Many-body localization in a long range XXZ model with random-field

NASA Astrophysics Data System (ADS)

Li, Bo

2016-12-01

Many-body localization (MBL) in a long range interaction XXZ model with random field are investigated. Using the exact diagonal method, the MBL phase diagram with different tuning parameters and interaction range is obtained. It is found that the phase diagram of finite size results supplies strong evidence to confirm that the threshold interaction exponent α = 2. The tuning parameter Δ can efficiently change the MBL edge in high energy density stats, thus the system can be controlled to transfer from thermal phase to MBL phase by changing Δ. The energy level statistics data are consistent with result of the MBL phase diagram. However energy level statistics data cannot detect the thermal phase correctly in extreme long range case.

Determination of molecular spectroscopic parameters and energy-transfer rates by double-resonance spectroscopy

NASA Technical Reports Server (NTRS)

Steinfeld, J. I.; Foy, B.; Hetzler, J.; Flannery, C.; Klaassen, J.; Mizugai, Y.; Coy, S.

1990-01-01

The spectroscopy of small to medium-size polyatomic molecules can be extremely complex, especially in higher-lying overtone and combination vibrational levels. The high density of levels also complicates the understanding of inelastic collision processes, which is required to model energy transfer and collision broadening of spectral lines. Both of these problems can be addressed by double-resonance spectroscopy, i.e., time-resolved pump-probe measurements using microwave, infrared, near-infrared, and visible-wavelength sources. Information on excited-state spectroscopy, transition moments, inelastic energy transfer rates and propensity rules, and pressure-broadening parameters may be obtained from such experiments. Examples are given for several species of importance in planetary atmospheres, including ozone, silane, ethane, and ammonia.

Electronic properties of deep-level defects in proton irradiated AlGaAs-GaAs solar cells

NASA Technical Reports Server (NTRS)

Li, S. S.

1981-01-01

Deep level transient spectroscopy and capacitance voltage techniques as well as analysis of the forward current voltage (I-V) characteristics and SEM-EIC data were carried out for proton irradiated GaAs solar cells over a wide range of proton energies and proton fluences. Defect and recombination parameters such as defect energy levels and density, carrier capture cross sections and lifetimes as well as diffusion lengths in the undoped n-GaAs LPE layers were determined. Good correlation between these defect parameters and solar cell performance parameters was obtained for GaAs solar cells irradiated by 200 and 290 KeV protons. It was found that 200 to 290 KeV protons will produce the most defects and damages to the GaAs solar cell structure used. The influence of the low temperature (200 to 400 C) periodic thermal annealing on the deep level defects and the performance of the 200 KeV proton irradiated cells is discussed.

Energy characteristics of Darrieus rotor ( review)

NASA Astrophysics Data System (ADS)

Gorelov, D. N.

2010-09-01

Presented below is the review of the results of experimental studies of energy characteristics of Darrieus rotor with vertical rotation axis. Influence of main geometry parameters of the rotor on its energy characteristics has been analyzed. It is shown that Darrieus rotor may have the higher level of energy characteristics than the best propeller wind turbines.

Theoretical study of the crystal-field energy levels and two-photon absorption intensities of Tb3+ in cubic host lattices.

PubMed

Duan, Chang-Kui; Tanner, Peter A

2011-03-17

Published two photon excitation (TPE) intensities for the cubic elpasolite systems Cs(2)NaTbX(6) (X = Cl, F) have been simulated by a calculation of two photon absorption (TPA) intensities which takes into account electric dipole transitions involving the detailed crystal-field structure of 4f(7)5d intermediate states, as well as the interactions of the 4f(7) core with the d-electron. The intensity calculation employed parameters from an energy level calculation which not only presented an accurate fit, but also yielded parameters consistent with those from other lanthanide ions. The calculated intensities were used to confirm or adjust the previous assignments of energy levels, resulting in some minor revisions. Generally, the TPA intensity simulations were in better agreement with experimental data for the fluoride, rather than the chloride, system and possible reasons for this are given.

Spectrum and energy levels of six-times ionized yttrium (Y VII)

NASA Astrophysics Data System (ADS)

Reader, Joseph

2018-03-01

The spectrum of six-times ionized yttrium, Y VII, was photographed with a sliding-spark discharge on 10.7 m normal- and grazing-incidence spectrographs. The region of observation was 157-824 Å. The observations extend the known configurations 4s24p3, 4s4p4, 4p5, 4s24p25s, 4s24p26s to the nearly complete 4s24p24d configuration. Our results for 4s24p24d significantly revise results of Rahimullah et al (1978 Phys. Scr. 18 96); Ateqad et al (1984 J. Phys. B: At. Mol. Phys. 17 4617). A total of 168 lines and 56 energy levels are now known for this ion. The observed configurations were interpreted with Hartree-Fock calculations and least-squares fits of the energy parameters to the observed levels. Transition probabilities for all classified lines were calculated with the fitted parameters.

Figures of merit for present and future dark energy probes

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

Mortonson, Michael J.; Huterer, Dragan; Hu, Wayne

2010-09-15

We compare current and forecasted constraints on dynamical dark energy models from Type Ia supernovae and the cosmic microwave background using figures of merit based on the volume of the allowed dark energy parameter space. For a two-parameter dark energy equation of state that varies linearly with the scale factor, and assuming a flat universe, the area of the error ellipse can be reduced by a factor of {approx}10 relative to current constraints by future space-based supernova data and CMB measurements from the Planck satellite. If the dark energy equation of state is described by a more general basis ofmore » principal components, the expected improvement in volume-based figures of merit is much greater. While the forecasted precision for any single parameter is only a factor of 2-5 smaller than current uncertainties, the constraints on dark energy models bounded by -1{<=}w{<=}1 improve for approximately 6 independent dark energy parameters resulting in a reduction of the total allowed volume of principal component parameter space by a factor of {approx}100. Typical quintessence models can be adequately described by just 2-3 of these parameters even given the precision of future data, leading to a more modest but still significant improvement. In addition to advances in supernova and CMB data, percent-level measurement of absolute distance and/or the expansion rate is required to ensure that dark energy constraints remain robust to variations in spatial curvature.« less

Energy levels of a hydrogenic impurity in a parabolic quantum well with a magnetic field

NASA Astrophysics Data System (ADS)

Zang, J. X.; Rustgi, M. L.

1993-07-01

In this paper, we present a calculation of the energy levels of a hydrogenic impurity (or a hydrogenic atom) at the bottom of a one-dimensional parabolic quantum well with a magnetic field normal to the plane of the well. The finite-basis-set variational method is used to calculate the ground state and the excited states with major quantum number less than or equal to 3. The limit of small radial distance and the limit of great radial distance are considered to choose a set of proper basis functions. The results in the limit that the parabolic parameter α=0 are compared with the data of Rösner et al. [J. Phys. B 17, 29 (1984)]. The comparison shows that the present calculation is quite accurate. It is found that the energy levels increase with increasing parabolic parameter α and increase with increasing normalized magnetic-field strength γ except those levels with magnetic quantum number m<0 at small γ.

From Dimer to Crystal: Calculating the Cohesive Energy of Rare Gas Solids

ERIC Educational Resources Information Center

Halpern, Arthur M.

2012-01-01

An upper-level undergraduate project is described in which students perform high-level ab initio computational scans of the potential energy curves for Ne[subscript 2] and Ar[subscript 2] and obtain the respective Lennard-Jones (LJ) potential parameters [sigma] and [epsilon] for the dimers. Using this information, along with the summation of…

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

Öner, Nazmiye, E-mail: fizikcinaz@gmail.com; Tamer, Ömer, E-mail: omertamer@sakarya.edu.tr; Avci, Davut, E-mail: davci@sakarya.edu.tr

Quantum mechanical calculations on cis-2, 6-bis (2-chlorophenyl)-3, 3-dimethylpiperidin-4-one were performed by using HSEH1PBE level of density functional theory (DFT) with 6-311++G (d, p) basis set. Geometric parameters of the title molecule in the ground state were found to be in good agreement with experimental data. The frontier molecular orbitals (HOMO and LUMO) were simulated by the same level. Small energy gap between the HOMO and LUMO is an indicator molecular charge transfer within the title molecule. The electronegativity, chemical hardness and softness were also calculated by using HOMO and LUMO energies. Dipole moment, polarizability and hyperpolarizability parameters were also calculatedmore » by using HSEH1PBE level. All calculations were carried out with the GAUSSIAN 09 package program.« less

Evaluation of calibration efficacy under different levels of uncertainty

DOE PAGES

Heo, Yeonsook; Graziano, Diane J.; Guzowski, Leah; ...

2014-06-10

This study examines how calibration performs under different levels of uncertainty in model input data. It specifically assesses the efficacy of Bayesian calibration to enhance the reliability of EnergyPlus model predictions. A Bayesian approach can be used to update uncertain values of parameters, given measured energy-use data, and to quantify the associated uncertainty.We assess the efficacy of Bayesian calibration under a controlled virtual-reality setup, which enables rigorous validation of the accuracy of calibration results in terms of both calibrated parameter values and model predictions. Case studies demonstrate the performance of Bayesian calibration of base models developed from audit data withmore » differing levels of detail in building design, usage, and operation.« less

DFTB Parameters for the Periodic Table, Part 2: Energies and Energy Gradients from Hydrogen to Calcium.

PubMed

Oliveira, Augusto F; Philipsen, Pier; Heine, Thomas

2015-11-10

In the first part of this series, we presented a parametrization strategy to obtain high-quality electronic band structures on the basis of density-functional-based tight-binding (DFTB) calculations and published a parameter set called QUASINANO2013.1. Here, we extend our parametrization effort to include the remaining terms that are needed to compute the total energy and its gradient, commonly referred to as repulsive potential. Instead of parametrizing these terms as a two-body potential, we calculate them explicitly from the DFTB analogues of the Kohn-Sham total energy expression. This strategy requires only two further numerical parameters per element. Thus, the atomic configuration and four real numbers per element are sufficient to define the DFTB model at this level of parametrization. The QUASINANO2015 parameter set allows the calculation of energy, structure, and electronic structure of all systems composed of elements ranging from H to Ca. Extensive benchmarks show that the overall accuracy of QUASINANO2015 is comparable to that of well-established methods, including PM7 and hand-tuned DFTB parameter sets, while coverage of a much larger range of chemical systems is available.

Nuclear Track Detector Characterization via Alpha-Spectrometry for Radioprotection Use

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

Morelli, D.; Imme, G.; Catalano, R.

2011-12-13

Solid Nuclear Track Detectors (SNTDs), CR-39 type, are usually adopted to monitor radon gas concentrations. In order to characterize the detectors according to track geometrical parameters, detectors were irradiated inside a vacuum chamber by alpha particles at twelve energy values, obtained by different Mylar foils in front of a {sup 241}Am source. The alpha energy values were verified using a Si detector. After the exposure to the alpha particles, the detectors were chemically etched to enlarge the tracks, which were then analyzed by means of a semiautomatic system composed of an optical microscope equipped with a CCD camera connected tomore » a personal computer to store images. A suitable routine analyzed the track parameters: major and minor axis length and mean grey level, allowing us to differentiate tracks according to the incident alpha energy and then to individuate the discrimination factors for radon alpha tracks. The combined use of geometrical and optical parameters allows one to overcome the ambiguity in the alpha energy determination due to the non-monotonicity of each parameter versus energy. After track parameter determination, a calibration procedure was performed by means of a radon chamber. The calibration was verified through an inter-comparing survey.« less

Fine-structure constant constraints on dark energy. II. Extending the parameter space

NASA Astrophysics Data System (ADS)

Martins, C. J. A. P.; Pinho, A. M. M.; Carreira, P.; Gusart, A.; López, J.; Rocha, C. I. S. A.

2016-01-01

Astrophysical tests of the stability of fundamental couplings, such as the fine-structure constant α , are a powerful probe of new physics. Recently these measurements, combined with local atomic clock tests and Type Ia supernova and Hubble parameter data, were used to constrain the simplest class of dynamical dark energy models where the same degree of freedom is assumed to provide both the dark energy and (through a dimensionless coupling, ζ , to the electromagnetic sector) the α variation. One caveat of these analyses was that it was based on fiducial models where the dark energy equation of state was described by a single parameter (effectively its present day value, w0). Here we relax this assumption and study broader dark energy model classes, including the Chevallier-Polarski-Linder and early dark energy parametrizations. Even in these extended cases we find that the current data constrains the coupling ζ at the 1 0-6 level and w0 to a few percent (marginalizing over other parameters), thus confirming the robustness of earlier analyses. On the other hand, the additional parameters are typically not well constrained. We also highlight the implications of our results for constraints on violations of the weak equivalence principle and improvements to be expected from forthcoming measurements with high-resolution ultrastable spectrographs.

Relative mass distributions of neutron-rich thermally fissile nuclei within a statistical model

NASA Astrophysics Data System (ADS)

Kumar, Bharat; Kannan, M. T. Senthil; Balasubramaniam, M.; Agrawal, B. K.; Patra, S. K.

2017-09-01

We study the binary mass distribution for the recently predicted thermally fissile neutron-rich uranium and thorium nuclei using a statistical model. The level density parameters needed for the study are evaluated from the excitation energies of the temperature-dependent relativistic mean field formalism. The excitation energy and the level density parameter for a given temperature are employed in the convolution integral method to obtain the probability of the particular fragmentation. As representative cases, we present the results for the binary yields of 250U and 254Th. The relative yields are presented for three different temperatures: T =1 , 2, and 3 MeV.

Accidental degeneracies in nonlinear quantum deformed systems

NASA Astrophysics Data System (ADS)

Aleixo, A. N. F.; Balantekin, A. B.

2011-09-01

We construct a multi-parameter nonlinear deformed algebra for quantum confined systems that includes many other deformed models as particular cases. We demonstrate that such systems exhibit the property of accidental pairwise energy level degeneracies. We also study, as a special case of our multi-parameter deformation formalism, the extension of the Tamm-Dancoff cutoff deformed oscillator and the occurrence of accidental pairwise degeneracy in the energy levels of the deformed system. As an application, we discuss the case of a trigonometric Rosen-Morse potential, which is successfully used in models for quantum confined systems, ranging from electrons in quantum dots to quarks in hadrons.

Theoretical Study of Electronic Structure and Thermoelectric Properties of Doped CuAlO2

NASA Astrophysics Data System (ADS)

Poopanya, P.; Yangthaisong, A.; Rattanapun, C.; Wichainchai, A.

2011-05-01

The doping level dependence of thermoelectric properties of delafossite CuAlO2 has been investigated in the constant scattering time ( τ) approximation, starting from the first principles of electronic structure. In particular, the lattice parameters and the energy band structure were calculated using the total energy plane-wave pseudopotential method. It was found that the lattice parameters of CuAlO2 are a = 2.802 Å and c = 16.704 Å, and the internal parameter is u = 0.1097. CuAlO2 has an indirect band gap of 2.17 eV and a direct gap of 3.31 eV. The calculated energy band structures were then used to calculate the electrical transport coefficients of CuAlO2. By considering the effects of doping level and temperature, it was found that the Seebeck coefficient S( T) increases with increasing acceptor doping ( A d) level. The values of S( T) in our experiments correspond to an A d level at 0.262 eV, which is identified as the Fermi level of CuAlO2. Based on our experimental Seebeck coefficient and the electrical conductivity, the constant relaxation time is estimated to be 1 × 10-16 s. The power factor is large for a low A d level and increases with temperature. It is suggested that delafossite CuAlO2 can be considered as a promising thermoelectric oxide material at high doping and high temperature.

Minimal nuclear energy density functional

NASA Astrophysics Data System (ADS)

Bulgac, Aurel; Forbes, Michael McNeil; Jin, Shi; Perez, Rodrigo Navarro; Schunck, Nicolas

2018-04-01

We present a minimal nuclear energy density functional (NEDF) called "SeaLL1" that has the smallest number of possible phenomenological parameters to date. SeaLL1 is defined by seven significant phenomenological parameters, each related to a specific nuclear property. It describes the nuclear masses of even-even nuclei with a mean energy error of 0.97 MeV and a standard deviation of 1.46 MeV , two-neutron and two-proton separation energies with rms errors of 0.69 MeV and 0.59 MeV respectively, and the charge radii of 345 even-even nuclei with a mean error ɛr=0.022 fm and a standard deviation σr=0.025 fm . SeaLL1 incorporates constraints on the equation of state (EoS) of pure neutron matter from quantum Monte Carlo calculations with chiral effective field theory two-body (NN ) interactions at the next-to-next-to-next-to leading order (N3LO) level and three-body (NNN ) interactions at the next-to-next-to leading order (N2LO) level. Two of the seven parameters are related to the saturation density and the energy per particle of the homogeneous symmetric nuclear matter, one is related to the nuclear surface tension, two are related to the symmetry energy and its density dependence, one is related to the strength of the spin-orbit interaction, and one is the coupling constant of the pairing interaction. We identify additional phenomenological parameters that have little effect on ground-state properties but can be used to fine-tune features such as the Thomas-Reiche-Kuhn sum rule, the excitation energy of the giant dipole and Gamow-Teller resonances, the static dipole electric polarizability, and the neutron skin thickness.

Minimal nuclear energy density functional

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

Bulgac, Aurel; Forbes, Michael McNeil; Jin, Shi

Inmore » this paper, we present a minimal nuclear energy density functional (NEDF) called “SeaLL1” that has the smallest number of possible phenomenological parameters to date. SeaLL1 is defined by seven significant phenomenological parameters, each related to a specific nuclear property. It describes the nuclear masses of even-even nuclei with a mean energy error of 0.97 MeV and a standard deviation of 1.46 MeV , two-neutron and two-proton separation energies with rms errors of 0.69 MeV and 0.59 MeV respectively, and the charge radii of 345 even-even nuclei with a mean error ε r = 0.022 fm and a standard deviation σ r = 0.025 fm . SeaLL1 incorporates constraints on the equation of state (EoS) of pure neutron matter from quantum Monte Carlo calculations with chiral effective field theory two-body ( NN ) interactions at the next-to-next-to-next-to leading order (N3LO) level and three-body ( NNN ) interactions at the next-to-next-to leading order (N2LO) level. Two of the seven parameters are related to the saturation density and the energy per particle of the homogeneous symmetric nuclear matter, one is related to the nuclear surface tension, two are related to the symmetry energy and its density dependence, one is related to the strength of the spin-orbit interaction, and one is the coupling constant of the pairing interaction. Finally, we identify additional phenomenological parameters that have little effect on ground-state properties but can be used to fine-tune features such as the Thomas-Reiche-Kuhn sum rule, the excitation energy of the giant dipole and Gamow-Teller resonances, the static dipole electric polarizability, and the neutron skin thickness.« less

Minimal nuclear energy density functional

DOE PAGES

Bulgac, Aurel; Forbes, Michael McNeil; Jin, Shi; ...

2018-04-17

Inmore » this paper, we present a minimal nuclear energy density functional (NEDF) called “SeaLL1” that has the smallest number of possible phenomenological parameters to date. SeaLL1 is defined by seven significant phenomenological parameters, each related to a specific nuclear property. It describes the nuclear masses of even-even nuclei with a mean energy error of 0.97 MeV and a standard deviation of 1.46 MeV , two-neutron and two-proton separation energies with rms errors of 0.69 MeV and 0.59 MeV respectively, and the charge radii of 345 even-even nuclei with a mean error ε r = 0.022 fm and a standard deviation σ r = 0.025 fm . SeaLL1 incorporates constraints on the equation of state (EoS) of pure neutron matter from quantum Monte Carlo calculations with chiral effective field theory two-body ( NN ) interactions at the next-to-next-to-next-to leading order (N3LO) level and three-body ( NNN ) interactions at the next-to-next-to leading order (N2LO) level. Two of the seven parameters are related to the saturation density and the energy per particle of the homogeneous symmetric nuclear matter, one is related to the nuclear surface tension, two are related to the symmetry energy and its density dependence, one is related to the strength of the spin-orbit interaction, and one is the coupling constant of the pairing interaction. Finally, we identify additional phenomenological parameters that have little effect on ground-state properties but can be used to fine-tune features such as the Thomas-Reiche-Kuhn sum rule, the excitation energy of the giant dipole and Gamow-Teller resonances, the static dipole electric polarizability, and the neutron skin thickness.« less

Experimental and theoretical studies on solar energy for energy conversion

NASA Technical Reports Server (NTRS)

Thomas, A. P.; Thekaekara, M. P.

1976-01-01

This paper presents the results of investigations made experimentally and theoretically to evaluate the various parameters that affect the amount of solar energy received on a collector surface. Measurements were made over a long period of time using both pyranometer and pyrheliometer. Computation of spectral and total irradiance at ground level have been made for a large variety of combinations of atmospheric parameters for ozone density, precipitable water vapor, turbidity-coefficients and air mass. A study of the air mass as a function of irradiance measured at GSFC, and comparison of the data with the computed values of total direct solar irradiance for various parameters indicate that turbidity changes with time of the day; atmospheric opacity is less in the afternoon than in the morning.

Crystal-field energy level analysis for Nd(3+) ions at the low symmetry C(1) site in [Nd(hfa)(4)(H(2)O)](N(C(2)H(5))(4)) single crystals.

PubMed

Mech, Agnieszka; Gajek, Zbigniew; Karbowiak, Mirosław; Rudowicz, Czesław

2008-09-24

Optical absorption measurements of Nd(3+) ions in single crystals of [Nd(hfa)(4)(H(2)O)](N(C(2)H(5))(4)) (hfa = hexafluoroacetyloacetonate), denoted Nd(hfa) for short, have been carried out at 4.2 and 298 K. This compound crystallizes in the monoclinic system (space group P 2(1)/n). Each Nd ion is coordinated to eight oxygen atoms that originate from the hexafluoroacetylacetonate ligands and one oxygen atom from the water molecule. A total of 85 experimental crystal-field (CF) energy levels arising from the Nd(3+) (4f(3)) electronic configuration were identified in the optical spectra and assigned. A three-step CF analysis was carried out in terms of a parametric Hamiltonian for the actual C(1) symmetry at the Nd(3+) ion sites. In the first step, a total of 27 CF parameters (CFPs) in the Wybourne notation B(kq), admissible by group theory, were determined in a preliminary fitting constrained by the angular overlap model predictions. The resulting CFP set was reduced to 24 specific independent CFPs using appropriate standardization transformations. Optimizations of the second-rank CFPs and extended scanning of the parameter space were employed in the second step to improve reliability of the CFP sets, which is rather a difficult task in the case of no site symmetry. Finally, seven free-ion parameters and 24 CFPs were freely varied, yielding an rms deviation between the calculated energy levels and the 85 observed ones of 11.1 cm(-1). Our approach also allows prediction of the energy levels of Nd(3+) ions that are hidden in the spectral range overlapping with strong ligand absorption, which is essential for understanding the inter-ionic energy transfer. The orientation of the axis system associated with the fitted CF parameters w.r.t. the crystallographic axes is established. The procedure adopted in our calculations may be considered as a general framework for analysis of CF levels of lanthanide ions at low (triclinic) symmetry sites.

Crystal-field energy level analysis for Nd3+ ions at the low symmetry C1 site in [Nd(hfa)4(H2O)](N(C2H5)4) single crystals

NASA Astrophysics Data System (ADS)

Mech, Agnieszka; Gajek, Zbigniew; Karbowiak, Mirosław; Rudowicz, Czesław

2008-09-01

Optical absorption measurements of Nd3+ ions in single crystals of [Nd(hfa)4(H2O)](N(C2H5)4) (hfa = hexafluoroacetyloacetonate), denoted Nd(hfa) for short, have been carried out at 4.2 and 298 K. This compound crystallizes in the monoclinic system (space group P 21/n). Each Nd ion is coordinated to eight oxygen atoms that originate from the hexafluoroacetylacetonate ligands and one oxygen atom from the water molecule. A total of 85 experimental crystal-field (CF) energy levels arising from the Nd3+ (4f3) electronic configuration were identified in the optical spectra and assigned. A three-step CF analysis was carried out in terms of a parametric Hamiltonian for the actual C1 symmetry at the Nd3+ ion sites. In the first step, a total of 27 CF parameters (CFPs) in the Wybourne notation Bkq, admissible by group theory, were determined in a preliminary fitting constrained by the angular overlap model predictions. The resulting CFP set was reduced to 24 specific independent CFPs using appropriate standardization transformations. Optimizations of the second-rank CFPs and extended scanning of the parameter space were employed in the second step to improve reliability of the CFP sets, which is rather a difficult task in the case of no site symmetry. Finally, seven free-ion parameters and 24 CFPs were freely varied, yielding an rms deviation between the calculated energy levels and the 85 observed ones of 11.1 cm-1. Our approach also allows prediction of the energy levels of Nd3+ ions that are hidden in the spectral range overlapping with strong ligand absorption, which is essential for understanding the inter-ionic energy transfer. The orientation of the axis system associated with the fitted CF parameters w.r.t. the crystallographic axes is established. The procedure adopted in our calculations may be considered as a general framework for analysis of CF levels of lanthanide ions at low (triclinic) symmetry sites.

Community Design for Optimal Energy and Resource Utilization.

ERIC Educational Resources Information Center

Bilenky, Stephen; And Others

Presented is a study which investigated the energy and resource dynamics of a semi-autonomous domestic system for 30 people. The investigation is organized on three levels: (1) developing a preliminary design and design parameters; (2) development and quantification of the energy and resource dynamics; and (3) designing a model to extrapolate…

New look at the Badger-Bauer rule: Correlations of spectroscopic IR and NMR parameters with hydrogen bond energy and geometry. FHF complexes

NASA Astrophysics Data System (ADS)

Tupikina, E. Yu.; Denisov, G. S.; Melikova, S. M.; Kucherov, S. Yu.; Tolstoy, P. M.

2018-07-01

In this work correlation dependencies between hydrogen bond energy ΔE for complexes with Fsbnd H⋯F hydrogen bond and their spectroscopic characteristics of the IR and NMR spectra are presented. We considered 26 complexes in a wide hydrogen bond energy range 0.2-47 kcal/mol. For each complex we calculated complexation energy (MP2/6-311++G(d,p)), IR spectroscopic parameters (FH stretching frequency ν, FH stretching frequency in local mode approximation νLM at MP2/6-311++G(d,p) level) and NMR parameters (chemical shift of hydrogen δH and fluorine nuclei δF, Nuclear Independent Chemical Shielding and spin-spin coupling constants 1JFH, 1hJH...F, 2hJFF at B3LYP/pcSseg-2 level). It was shown that changes of parameters upon complexation, i.e. changes of the stretching frequency in local mode approximation ΔνLM, change of the proton chemical shift ΔδH and change of the absolute value of spin-spin coupling constant 1JFH could be used for estimation of corresponding hydrogen bond strength. Furthermore, we build correlation dependencies between abovementioned spectroscopic characteristics and geometric ones, such as the asymmetry of bridging proton position q1 = 0.5·(rFH - rH…F).

NEUTRON ENERGY LEVELS IN A DIFFUSE POTENTIAL

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

Ghosh, A.; Sil, N.C.

1960-06-01

The energy eigenvalues of neutrons within the nucleus for a spherically symmetrical potential V(r) = --V/sub 0/STAl + exp{(r-- R)/a}!/sup -1/ are investigated by following a new method of Lanczos for solving the differential equation. The s- and p-state energy levels are calculated for atomic mass 200 with the values of parameters adopted by Feshbach et al. in their calculation of the neutron strength function with a similar potential. The results of the calculation agree closely with those of Malenka. (auth)

Parametrization of free ion levels of four isoelectronic 4f2 systems: Insights into configuration interaction parameters

NASA Astrophysics Data System (ADS)

Yeung, Yau Yuen; Tanner, Peter A.

2013-12-01

The experimental free ion 4f2 energy level data sets comprising 12 or 13 J-multiplets of La+, Ce2+, Pr3+ and Nd4+ have been fitted by a semiempirical atomic Hamiltonian comprising 8, 10, or 12 freely-varying parameters. The root mean square errors were 16.1, 1.3, 0.3 and 0.3 cm-1, respectively for fits with 10 parameters. The fitted inter-electronic repulsion and magnetic parameters vary linearly with ionic charge, i, but better linear fits are obtained with (4-i)2, although the reason is unclear at present. The two-body configuration interaction parameters α and β exhibit a linear relation with [ΔE(bc)]-1, where ΔE(bc) is the energy difference between the 4f2 barycentre and that of the interacting configuration, namely 4f6p for La+, Ce2+, and Pr3+, and 5p54f3 for Nd4+. The linear fit provides the rationale for the negative value of α for the case of La+, where the interacting configuration is located below 4f2.

Variations of seismic parameters during different activity levels of the Soufriere Hills Volcano, Montserrat

NASA Astrophysics Data System (ADS)

Powell, T.; Neuberg, J.

2003-04-01

The low-frequency seismic events on Montserrat are linked to conduit resonance and the pressurisation of the volcanic system. Analysis of these events tell us more about the behaviour of the volcanic system and provide a monitoring and interpretation tool. We have written an Automated Event Classification Algorithm Program (AECAP), which finds and classifies seismic events and calculates seismic parameters such as energy, intermittency, peak frequency and event duration. Comparison of low-frequency energy with the tilt cycles in 1997 allows us to link pressurisation of the volcano with seismic behaviour. An empirical relationship provides us with an estimate of pressurisation through released seismic energy. During 1997, the activity of the volcano varied considerably. We compare seismic parameters from quiet periods to those from active periods and investigate how the relationships between these parameters change. These changes are then used to constrain models of magmatic processes during different stages of volcanic activity.

Electric arc discharge damage to ion thruster grids

NASA Technical Reports Server (NTRS)

Beebe, D. D.; Nakanishi, S.; Finke, R. C.

1974-01-01

Arcs representative of those occurring between the grids of a mercury ion thruster were simulated. Parameters affecting an arc and the resulting damage were studied. The parameters investigated were arc energy, arc duration, and grid geometry. Arc attenuation techniques were also investigated. Potentially serious damage occurred at all energy levels representative of actual thruster operating conditions. Of the grids tested, the lowest open-area configuration sustained the least damage for given conditions. At a fixed energy level a long duration discharge caused greater damage than a short discharge. Attenuation of arc current using various impedances proved to be effective in reducing arc damage. Faults were also deliberately caused using chips of sputtered materials formed during the operation of an actual thruster. These faults were cleared with no serious grid damage resulting using the principles and methods developed in this study.

Hydrogen Pathways: Updated Cost, Well-to-Wheels Energy Use, and Emissions for the Current Technology Status of Ten Hydrogen Production, Delivery, and Distribution Scenarios

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

Ramsden, T.; Ruth, M.; Diakov, V.

2013-03-01

This report describes a life-cycle assessment conducted by the National Renewable Energy Laboratory (NREL) of 10 hydrogen production, delivery, dispensing, and use pathways that were evaluated for cost, energy use, and greenhouse gas (GHG) emissions. This evaluation updates and expands on a previous assessment of seven pathways conducted in 2009. This study summarizes key results, parameters, and sensitivities to those parameters for the 10 hydrogen pathways, reporting on the levelized cost of hydrogen in 2007 U.S. dollars as well as life-cycle well-to-wheels energy use and GHG emissions associated with the pathways.

A new class of energy based control laws for revolute robot arms - Tracking control, robustness enhancement and adaptive control

NASA Technical Reports Server (NTRS)

Wen, John T.; Kreutz, Kenneth; Bayard, David S.

1988-01-01

A class of joint-level control laws for all-revolute robot arms is introduced. The analysis is similar to the recently proposed energy Liapunov function approach except that the closed-loop potential function is shaped in accordance with the underlying joint space topology. By using energy Liapunov functions with the modified potential energy, a much simpler analysis can be used to show closed-loop global asymptotic stability and local exponential stability. When Coulomb and viscous friction and model parameter errors are present, a sliding-mode-like modification of the control law is proposed to add a robustness-enhancing outer loop. Adaptive control is also addressed within the same framework. A linear-in-the-parameters formulation is adopted, and globally asymptotically stable adaptive control laws are derived by replacing the model parameters in the nonadaptive control laws by their estimates.

Design Parameters of a Miniaturized Piezoelectric Underwater Acoustic Transmitter

PubMed Central

Li, Huidong; Deng, Zhiqun Daniel; Yuan, Yong; Carlson, Thomas J.

2012-01-01

PZT ceramics have been widely used in underwater acoustic transducers. However, literature available discussing the design parameters of a miniaturized PZT-based low-duty-cycle transmitter is very limited. This paper discusses some of the design parameters—the backing material, driving voltage, PZT material type, power consumption and the transducer length of a miniaturized acoustic fish tag using a PZT tube. Four different types of PZT were evaluated with respect to the source level, energy consumption and bandwidth of the transducer. The effect of the tube length on the source level is discussed. The results demonstrate that ultralow-density closed-cell foam is the best backing material for the PZT tube. The Navy Type VI PZTs provide the best source level with relatively low energy consumption and that a low transducer capacitance is preferred for high efficiency. A 35% reduction in the transducer length results in 2 dB decrease in source level. PMID:23012534

Quantifying Adoption Rates and Energy Savings Over Time for Advanced Manufacturing Technologies

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

Hanes, Rebecca; Carpenter Petri, Alberta C; Riddle, Matt

Energy-efficient manufacturing technologies can reduce energy consumption and lower operating costs for an individual manufacturing facility, but increased process complexity and the resulting risk of disruption means that manufacturers may be reluctant to adopt such technologies. In order to quantify potential energy savings at scales larger than a single facility, it is necessary to account for how quickly and how widely the technology will be adopted by manufacturers. This work develops a methodology for estimating energy-efficient manufacturing technology adoption rates using quantitative, objectively measurable technology characteristics, including energetic, economic and technical criteria. Twelve technology characteristics are considered, and each characteristicmore » is assigned an importance weight that reflects its impact on the overall technology adoption rate. Technology characteristic data and importance weights are used to calculate the adoption score, a number between 0 and 1 that represents how quickly the technology is likely to be adopted. The adoption score is then used to estimate parameters for the Bass diffusion curve, which quantifies the change in the number of new technology adopters in a population over time. Finally, energy savings at the sector level are calculated over time by multiplying the number of new technology adopters at each time step with the technology's facility-level energy savings. The proposed methodology will be applied to five state-of-the-art energy-efficient technologies in the carbon fiber composites sector, with technology data obtained from the Department of Energy's 2016 bandwidth study. Because the importance weights used in estimating the Bass curve parameters are subjective, a sensitivity analysis will be performed on the weights to obtain a range of parameters for each technology. The potential energy savings for each technology and the rate at which each technology is adopted in the sector are quantified and used to identify the technologies which offer the greatest cumulative sector-level energy savings over a period of 20 years. Preliminary analysis indicates that relatively simple technologies, such as efficient furnaces, will be adopted more quickly and result in greater cumulative energy savings compared to more complex technologies that require process retrofitting, such as advanced control systems.« less

The influence of coal physical and mechanical properties and mining energy consumption factor on airborne respirable dust level

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

Koziel, A.; Malec, M.; Wardas, E.

1999-07-01

The fact that there are not any explicitly defined relationships describing the influence of physical and mechanical properties of coal and of energy consumption factor on dust level prompted Polish and American investigators to carry out a joint research project within the framework of the US-Poland Maria Sklodowska-Curie Joint Fund II. The paper presents methods used to perform tests under laboratory conditions at the Pittsburgh Research Laboratory as well as under real conditions in the course of coal cutting in Polish coal mines. Measuring systems and results of the tests are described. The analysis carried out has provided a basismore » for determining the influence of specified operational parameters, i.e., coal compression strength R{sub c}, coal cuttability factor A, energy consumption factor of mining E{sub uc}, load of cutting drums as well as of laboratory parameters, i.e., grindability, coal breakage characteristics (product size distribution), moisture content, volatile and fixed carbon content, specific energy of crushing on a level of generated dust (total dust, specific dust and airborne respirable dust). The effect of technical parameters, i.e., face height, airflow velocity in a face, amount and pressure of water in spraying systems of longwall shearers, depth of cut taken by a cutting drum and application of powered cowls on dust level under operating conditions are also presented. Results of the tests made it possible to work out guidelines relating to methods and technology for effective reduction of dust emission on longwall faces.« less

Complex assessment of urban housing energy sustainability

NASA Astrophysics Data System (ADS)

Popova, Olga; Glebova, Julia; Karakozova, Irina

2018-03-01

The article presents the results of a complex experimental-analytical research of residential development energy parameters - survey of construction sites and determination of calculated energy parameters (resistance to heat transfer) considering their technical condition. The authors suggest a methodology for assessing residential development energy parameters on the basis of construction project's structural analysis with the use of advanced intelligent collection systems, processing (self-organizing maps - SOM) and data visualization (geo-informational systems - GIS). SOM clustering permitted to divide the housing stock (on the example of Arkhangelsk city) into groups with similar technical-operational and energy parameters. It is also possible to measure energy parameters of construction project of each cluster by comparing them with reference (normative) measures and also with each other. The authors propose mechanisms for increasing the area's energy stability level by implementing a set of reproduction activities for residential development of various groups. The analysis showed that modern multilevel and high-rise construction buildings have the least heat losses. At present, however, ow-rise wood buildings is the dominant styles of buildings of Arkhangelsk city. Data visualisation on the created heat map showed that such housing stock covers the largest urban area. The development strategies for depressed areas is in a high-rise building, which show the economic, social and environmental benefits of upward growth of the city. An urban regeneration programme for severely rundown urban housing estates is in a high-rise construction building, which show the economic, social and environmental benefits of upward growth of the city.

Stark broadening parameter regularities and interpolation and critical evaluation of data for CP star atmospheres research: Stark line shifts

NASA Astrophysics Data System (ADS)

Dimitrijevic, M. S.; Tankosic, D.

1998-04-01

In order to find out if regularities and systematic trends found to be apparent among experimental Stark line shifts allow the accurate interpolation of new data and critical evaluation of experimental results, the exceptions to the established regularities are analysed on the basis of critical reviews of experimental data, and reasons for such exceptions are discussed. We found that such exceptions are mostly due to the situations when: (i) the energy gap between atomic energy levels within a supermultiplet is equal or comparable to the energy gap to the nearest perturbing levels; (ii) the most important perturbing level is embedded between the energy levels of the supermultiplet; (iii) the forbidden transitions have influence on Stark line shifts.

Gold nanoparticles alter parameters of oxidative stress and energy metabolism in organs of adult rats.

PubMed

Ferreira, Gabriela Kozuchovski; Cardoso, Eria; Vuolo, Francieli Silva; Michels, Monique; Zanoni, Elton Torres; Carvalho-Silva, Milena; Gomes, Lara Mezari; Dal-Pizzol, Felipe; Rezin, Gislaine Tezza; Streck, Emilio L; Paula, Marcos Marques da Silva

2015-12-01

This study evaluated the parameters of oxidative stress and energy metabolism after the acute and long-term administration of gold nanoparticles (GNPs, 10 and 30 nm in diameter) in different organs of rats. Adult male Wistar rats received a single intraperitoneal injection or repeated injections (once daily for 28 days) of saline solution, GNPs-10 or GNPs-30. Twenty-four hours after the last administration, the animals were killed, and the liver, kidney, and heart were isolated for biochemical analysis. We demonstrated that acute administration of GNPs-30 increased the TBARS levels, and that GNPs-10 increased the carbonyl protein levels. The long-term administration of GNPs-10 increased the TBARS levels, and the carbonyl protein levels were increased by GNPs-30. Acute administration of GNPs-10 and GNPs-30 increased SOD activity. Long-term administration of GNPs-30 increased SOD activity. Acute administration of GNPs-10 decreased the activity of CAT, whereas long-term administration of GNP-10 and GNP-30 altered CAT activity randomly. Our results also demonstrated that acute GNPs-30 administration decreased energy metabolism, especially in the liver and heart. Long-term GNPs-10 administration increased energy metabolism in the liver and decreased energy metabolism in the kidney and heart, whereas long-term GNPs-30 administration increased energy metabolism in the heart. The results of our study are consistent with other studies conducted in our research group and reinforce the fact that GNPs can lead to oxidative damage, which is responsible for DNA damage and alterations in energy metabolism.

Rock Cutting Depth Model Based on Kinetic Energy of Abrasive Waterjet

NASA Astrophysics Data System (ADS)

Oh, Tae-Min; Cho, Gye-Chun

2016-03-01

Abrasive waterjets are widely used in the fields of civil and mechanical engineering for cutting a great variety of hard materials including rocks, metals, and other materials. Cutting depth is an important index to estimate operating time and cost, but it is very difficult to predict because there are a number of influential variables (e.g., energy, geometry, material, and nozzle system parameters). In this study, the cutting depth is correlated to the maximum kinetic energy expressed in terms of energy (i.e., water pressure, water flow rate, abrasive feed rate, and traverse speed), geometry (i.e., standoff distance), material (i.e., α and β), and nozzle system parameters (i.e., nozzle size, shape, and jet diffusion level). The maximum kinetic energy cutting depth model is verified with experimental test data that are obtained using one type of hard granite specimen for various parameters. The results show a unique curve for a specific rock type in a power function between cutting depth and maximum kinetic energy. The cutting depth model developed here can be very useful for estimating the process time when cutting rock using an abrasive waterjet.

Optimal energy distribution of carbohydrate intake for Japanese elderly patients with type 2 diabetes: the Japanese Elderly Intervention Trial.

PubMed

Kamada, Chiemi; Yoshimura, Hidenori; Okumura, Ryota; Takahashi, Keiko; Iimuro, Satoshi; Ohashi, Yasuo; Araki, Atsushi; Umegaki, Hiroyuki; Sakurai, Takashi; Yoshimura, Yukio; Ito, Hideki

2012-04-01

In diet therapy for diabetes, optimal energy intake and the energy distribution of macronutrients (protein : fat : carbohydrate [PFC] energy ratio) are important. We aimed to clarify the correlation between the PFC energy ratio and metabolic parameters including glycated hemoglobin A1c (HbA1c) and triglycerides in Japanese elderly patients with type 2 diabetes mellitus aged 65 years or older. Participants were 1173 diabetic patients aged 65 years or older with serum HbA1c level of >/=7.4% enrolled in the Japanese Elderly Diabetes Intervention Trial (J-EDIT). The participants were divided into four groups by the percentage of total energy intake (%E) of carbohydrate (C1: less than 55%E, C2: 55%E or more and less than 60%E, C3: 60%E or more and less than 65%E, and C4: 65%E or more). Relations of %E of carbohydrate to HbA1c and other metabolic parameters, energy intake and nutritional intake were examined. Furthermore, the subjects were divided into four categories by HbA1c levels by quartile method (Q1: less than 7.90%, Q2: 7.90% or more and less than 8.30%, Q3: 8.30% or more and less than 8.80%, Q4: 8.80% or more). Relations of HbA1c to other metabolic parameters, energy intake and nutritional intake were examined. The mean HbA1c levels in the four groups were C1: 8.40%, C2: 8.50%, C3: 8.41% and C4: 8.36% in men, and C1: 8.51%, C2: 8.47%, C3: 8.35% and C4: 8.52% in women, respectively. There were no significant differences and linear trend in HbA1c levels across groups. The mean triglyceride levels were in the range of 122-128 mg/dL in men from C1 to C3, although it was significantly higher in C4 (177 mg/dL). The mean triglyceride levels were in the range of 128-136 mg/dL in women from C1 to C3, although it was significantly higher in Q4 (150 mg/dL). Amounts of protein and fat intakes decreased with an increase of %E of carbohydrate, although amount of carbohydrate intake did not change significantly. As a result, %E of protein and fat, and energy intake decreased in both men and women with an increase in %E of carbohydrate. Among the four quartiles divided by HbA1c levels, there were no significant differences in energy intake and PFC energy ratio. The present study suggests that, within the range studied, the carbohydrate energy ratio has no correlation with HbA1c levels. However, serum triglyceride levels increased and high-density lipoprotein cholesterol levels decreased significantly, with an increase of %E of carbohydrate in men, and the same tendencies were observed in women. Furthermore, in patients with 65%E or more of carbohydrate, serum triglyceride levels exceeded 150 mg/dL, which is the recommended treatment target for diabetic patients. These results suggest that the ideal %E of carbohydrate for Japanese elderly type 2 diabetes is less than 65. The lower limit of %E of carbohydrate could not be determined from the present study. © 2012 Japan Geriatrics Society.

Cobalt related defect levels in silicon analyzed by temperature- and injection-dependent lifetime spectroscopy

NASA Astrophysics Data System (ADS)

Diez, S.; Rein, S.; Roth, T.; Glunz, S. W.

2007-02-01

Temperature- and injection-dependent lifetime spectroscopy (TIDLS) as a method to characterize point defects in silicon with several energy levels is demonstrated. An intentionally cobalt-contaminated p-type wafer was investigated by means of lifetime measurements performed at different temperatures up to 151°C. Two defect energy levels were required to model the lifetime curves on basis of the Shockley-Read-Hall statistics. The detailed analysis is based on the determination of the recently introduced defect parameter solution surface (DPSS) in order to extract the underlying defect parameters. A unique solution has been found for a deep defect level located in the upper band gap half with an energy depth of EC-Et=0.38±0.01eV, with a corresponding ratio of capture cross sections k =σn/σp=0.16 within the interval of uncertainty of 0.06-0.69. Additionally, a deep donor level in the lower band gap half known from the literature could be assigned to a second energy level within the DPSS analysis at Et-EV=0.41±0.02eV with a corresponding ratio of capture cross sections k =σn/σp=16±3. An investigation of the temperature dependence of the capture cross section for electrons suggests that the underlying recombination process of the defect in the lower band gap half is driven by a two stage cascade capture with an activation energy of ΔE =52±2meV. These results show that TIDLS in combination with DPSS analysis is a powerful method to characterize even multiple defect levels that are affecting carrier recombination lifetime in parallel.

MITHRAS: A Program of Simultaneous Radar Observations of the High-Latitude Auroral Zone.

DTIC Science & Technology

1982-11-01

Latitude * and Time for Chatanika ..... ................. ... 38 111-5 Cross Polar Cap Potential Versus Solar-Wind Energy Parameter...49 vii 9 III-10 Scatter Plot of Pedersen Conductivities as a Function of Average Energy for Two Levels of Total...Precipitated Energy ....... ....... ......... .. 51 -IIl-1 For Initial Time and Steady State, (a) Latitudinal Profile of the Meridional Electric-Field

Level density inputs in nuclear reaction codes and the role of the spin cutoff parameter

DOE PAGES

Voinov, A. V.; Grimes, S. M.; Brune, C. R.; ...

2014-09-03

Here, the proton spectrum from the 57Fe(α,p) reaction has been measured and analyzed with the Hauser-Feshbach model of nuclear reactions. Different input level density models have been tested. It was found that the best description is achieved with either Fermi-gas or constant temperature model functions obtained by fitting them to neutron resonance spacing and to discrete levels and using the spin cutoff parameter with much weaker excitation energy dependence than it is predicted by the Fermi-gas model.

Impurity bound states in fully gapped d-wave superconductors with subdominant order parameters

PubMed Central

Mashkoori, Mahdi; Björnson, Kristofer; Black-Schaffer, Annica M.

2017-01-01

Impurities in superconductors and their induced bound states are important both for engineering novel states such as Majorana zero-energy modes and for probing bulk properties of the superconducting state. The high-temperature cuprates offer a clear advantage in a much larger superconducting order parameter, but the nodal energy spectrum of a pure d-wave superconductor only allows virtual bound states. Fully gapped d-wave superconducting states have, however, been proposed in several cuprate systems thanks to subdominant order parameters producing d + is- or d + id′-wave superconducting states. Here we study both magnetic and potential impurities in these fully gapped d-wave superconductors. Using analytical T-matrix and complementary numerical tight-binding lattice calculations, we show that magnetic and potential impurities behave fundamentally different in d + is- and d + id′-wave superconductors. In a d + is-wave superconductor, there are no bound states for potential impurities, while a magnetic impurity produces one pair of bound states, with a zero-energy level crossing at a finite scattering strength. On the other hand, a d + id′-wave symmetry always gives rise to two pairs of bound states and only produce a reachable zero-energy level crossing if the normal state has a strong particle-hole asymmetry. PMID:28281570

Chemical trend of acceptor levels of Be, Mg, Zn, and Cd in GaAs, GaP, InP and GaN

NASA Astrophysics Data System (ADS)

Wang, Hao; Chen, An-Ban

2000-03-01

We are investigating the “shallow” acceptor levels in the III-nitride semiconductors theoretically. The k·p Hamiltonians and a model central-cell impurity potential have been used to evaluate the ordering of the ionization energies of impurities Be, Mg, Zn, and Cd in GaN. The impurity potential parameters were obtained from studying the same set of impurities in GaAs. These parameters were then transferred to the calculation for other hosts, leaving only one adjustable screening parameter for each host. This procedure was tested in GaP and InP and remarkably good results were obtained. When applied to GaN, this procedure produced a consistent set of acceptor levels with different k·p Hamiltonians. The calculated ionization energies for Be, Mg, Zn and Cd acceptors in GaN are respectively145, 156, 192, and 312 meV for the zincblende structure, and 229, 250, 320, and 510 meV for the wurtzite structure. These and other results will be discussed.

Surface pretreatment of plastics with an atmospheric pressure plasma jet - Influence of generator power and kinematics

NASA Astrophysics Data System (ADS)

Moritzer, E.; Leister, C.

2014-05-01

The industrial use of atmospheric pressure plasmas in the plastics processing industry has increased significantly in recent years. Users of this treatment process have the possibility to influence the target values (e.g. bond strength or surface energy) with the help of kinematic and electrical parameters. Until now, systematic procedures have been used with which the parameters can be adapted to the process or product requirements but only by very time-consuming methods. For this reason, the relationship between influencing values and target values will be examined based on the example of a pretreatment in the bonding process with the help of statistical experimental design. Because of the large number of parameters involved, the analysis is restricted to the kinematic and electrical parameters. In the experimental tests, the following factors are taken as parameters: gap between nozzle and substrate, treatment velocity (kinematic data), voltage and duty cycle (electrical data). The statistical evaluation shows significant relationships between the parameters and surface energy in the case of polypropylene. An increase in the voltage and duty cycle increases the polar proportion of the surface energy, while a larger gap and higher velocity leads to lower energy levels. The bond strength of the overlapping bond is also significantly influenced by the voltage, velocity and gap. The direction of their effects is identical with those of the surface energy. In addition to the kinematic influences of the motion of an atmospheric pressure plasma jet, it is therefore especially important that the parameters for the plasma production are taken into account when designing the pretreatment processes.

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

Moritzer, E., E-mail: elmar.moritzer@ktp.upb.de; Leister, C., E-mail: elmar.moritzer@ktp.upb.de

The industrial use of atmospheric pressure plasmas in the plastics processing industry has increased significantly in recent years. Users of this treatment process have the possibility to influence the target values (e.g. bond strength or surface energy) with the help of kinematic and electrical parameters. Until now, systematic procedures have been used with which the parameters can be adapted to the process or product requirements but only by very time-consuming methods. For this reason, the relationship between influencing values and target values will be examined based on the example of a pretreatment in the bonding process with the help ofmore » statistical experimental design. Because of the large number of parameters involved, the analysis is restricted to the kinematic and electrical parameters. In the experimental tests, the following factors are taken as parameters: gap between nozzle and substrate, treatment velocity (kinematic data), voltage and duty cycle (electrical data). The statistical evaluation shows significant relationships between the parameters and surface energy in the case of polypropylene. An increase in the voltage and duty cycle increases the polar proportion of the surface energy, while a larger gap and higher velocity leads to lower energy levels. The bond strength of the overlapping bond is also significantly influenced by the voltage, velocity and gap. The direction of their effects is identical with those of the surface energy. In addition to the kinematic influences of the motion of an atmospheric pressure plasma jet, it is therefore especially important that the parameters for the plasma production are taken into account when designing the pretreatment processes.« less

RIPL - Reference Input Parameter Library for Calculation of Nuclear Reactions and Nuclear Data Evaluations

NASA Astrophysics Data System (ADS)

Capote, R.; Herman, M.; Obložinský, P.; Young, P. G.; Goriely, S.; Belgya, T.; Ignatyuk, A. V.; Koning, A. J.; Hilaire, S.; Plujko, V. A.; Avrigeanu, M.; Bersillon, O.; Chadwick, M. B.; Fukahori, T.; Ge, Zhigang; Han, Yinlu; Kailas, S.; Kopecky, J.; Maslov, V. M.; Reffo, G.; Sin, M.; Soukhovitskii, E. Sh.; Talou, P.

2009-12-01

We describe the physics and data included in the Reference Input Parameter Library, which is devoted to input parameters needed in calculations of nuclear reactions and nuclear data evaluations. Advanced modelling codes require substantial numerical input, therefore the International Atomic Energy Agency (IAEA) has worked extensively since 1993 on a library of validated nuclear-model input parameters, referred to as the Reference Input Parameter Library (RIPL). A final RIPL coordinated research project (RIPL-3) was brought to a successful conclusion in December 2008, after 15 years of challenging work carried out through three consecutive IAEA projects. The RIPL-3 library was released in January 2009, and is available on the Web through http://www-nds.iaea.org/RIPL-3/. This work and the resulting database are extremely important to theoreticians involved in the development and use of nuclear reaction modelling (ALICE, EMPIRE, GNASH, UNF, TALYS) both for theoretical research and nuclear data evaluations. The numerical data and computer codes included in RIPL-3 are arranged in seven segments: MASSES contains ground-state properties of nuclei for about 9000 nuclei, including three theoretical predictions of masses and the evaluated experimental masses of Audi et al. (2003). DISCRETE LEVELS contains 117 datasets (one for each element) with all known level schemes, electromagnetic and γ-ray decay probabilities available from ENSDF in October 2007. NEUTRON RESONANCES contains average resonance parameters prepared on the basis of the evaluations performed by Ignatyuk and Mughabghab. OPTICAL MODEL contains 495 sets of phenomenological optical model parameters defined in a wide energy range. When there are insufficient experimental data, the evaluator has to resort to either global parameterizations or microscopic approaches. Radial density distributions to be used as input for microscopic calculations are stored in the MASSES segment. LEVEL DENSITIES contains phenomenological parameterizations based on the modified Fermi gas and superfluid models and microscopic calculations which are based on a realistic microscopic single-particle level scheme. Partial level densities formulae are also recommended. All tabulated total level densities are consistent with both the recommended average neutron resonance parameters and discrete levels. GAMMA contains parameters that quantify giant resonances, experimental gamma-ray strength functions and methods for calculating gamma emission in statistical model codes. The experimental GDR parameters are represented by Lorentzian fits to the photo-absorption cross sections for 102 nuclides ranging from 51V to 239Pu. FISSION includes global prescriptions for fission barriers and nuclear level densities at fission saddle points based on microscopic HFB calculations constrained by experimental fission cross sections.

RIPL - Reference Input Parameter Library for Calculation of Nuclear Reactions and Nuclear Data Evaluations

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

Capote, R.; Herman, M.; Oblozinsky, P.

We describe the physics and data included in the Reference Input Parameter Library, which is devoted to input parameters needed in calculations of nuclear reactions and nuclear data evaluations. Advanced modelling codes require substantial numerical input, therefore the International Atomic Energy Agency (IAEA) has worked extensively since 1993 on a library of validated nuclear-model input parameters, referred to as the Reference Input Parameter Library (RIPL). A final RIPL coordinated research project (RIPL-3) was brought to a successful conclusion in December 2008, after 15 years of challenging work carried out through three consecutive IAEA projects. The RIPL-3 library was released inmore » January 2009, and is available on the Web through (http://www-nds.iaea.org/RIPL-3/). This work and the resulting database are extremely important to theoreticians involved in the development and use of nuclear reaction modelling (ALICE, EMPIRE, GNASH, UNF, TALYS) both for theoretical research and nuclear data evaluations. The numerical data and computer codes included in RIPL-3 are arranged in seven segments: MASSES contains ground-state properties of nuclei for about 9000 nuclei, including three theoretical predictions of masses and the evaluated experimental masses of Audi et al. (2003). DISCRETE LEVELS contains 117 datasets (one for each element) with all known level schemes, electromagnetic and {gamma}-ray decay probabilities available from ENSDF in October 2007. NEUTRON RESONANCES contains average resonance parameters prepared on the basis of the evaluations performed by Ignatyuk and Mughabghab. OPTICAL MODEL contains 495 sets of phenomenological optical model parameters defined in a wide energy range. When there are insufficient experimental data, the evaluator has to resort to either global parameterizations or microscopic approaches. Radial density distributions to be used as input for microscopic calculations are stored in the MASSES segment. LEVEL DENSITIES contains phenomenological parameterizations based on the modified Fermi gas and superfluid models and microscopic calculations which are based on a realistic microscopic single-particle level scheme. Partial level densities formulae are also recommended. All tabulated total level densities are consistent with both the recommended average neutron resonance parameters and discrete levels. GAMMA contains parameters that quantify giant resonances, experimental gamma-ray strength functions and methods for calculating gamma emission in statistical model codes. The experimental GDR parameters are represented by Lorentzian fits to the photo-absorption cross sections for 102 nuclides ranging from {sup 51}V to {sup 239}Pu. FISSION includes global prescriptions for fission barriers and nuclear level densities at fission saddle points based on microscopic HFB calculations constrained by experimental fission cross sections.« less

RIPL-Reference Input Parameter Library for Calculation of Nuclear Reactions and Nuclear Data Evaluations

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

Capote, R.; Herman, M.; Capote,R.

We describe the physics and data included in the Reference Input Parameter Library, which is devoted to input parameters needed in calculations of nuclear reactions and nuclear data evaluations. Advanced modelling codes require substantial numerical input, therefore the International Atomic Energy Agency (IAEA) has worked extensively since 1993 on a library of validated nuclear-model input parameters, referred to as the Reference Input Parameter Library (RIPL). A final RIPL coordinated research project (RIPL-3) was brought to a successful conclusion in December 2008, after 15 years of challenging work carried out through three consecutive IAEA projects. The RIPL-3 library was released inmore » January 2009, and is available on the Web through http://www-nds.iaea.org/RIPL-3/. This work and the resulting database are extremely important to theoreticians involved in the development and use of nuclear reaction modelling (ALICE, EMPIRE, GNASH, UNF, TALYS) both for theoretical research and nuclear data evaluations. The numerical data and computer codes included in RIPL-3 are arranged in seven segments: MASSES contains ground-state properties of nuclei for about 9000 nuclei, including three theoretical predictions of masses and the evaluated experimental masses of Audi et al. (2003). DISCRETE LEVELS contains 117 datasets (one for each element) with all known level schemes, electromagnetic and {gamma}-ray decay probabilities available from ENSDF in October 2007. NEUTRON RESONANCES contains average resonance parameters prepared on the basis of the evaluations performed by Ignatyuk and Mughabghab. OPTICAL MODEL contains 495 sets of phenomenological optical model parameters defined in a wide energy range. When there are insufficient experimental data, the evaluator has to resort to either global parameterizations or microscopic approaches. Radial density distributions to be used as input for microscopic calculations are stored in the MASSES segment. LEVEL DENSITIES contains phenomenological parameterizations based on the modified Fermi gas and superfluid models and microscopic calculations which are based on a realistic microscopic single-particle level scheme. Partial level densities formulae are also recommended. All tabulated total level densities are consistent with both the recommended average neutron resonance parameters and discrete levels. GAMMA contains parameters that quantify giant resonances, experimental gamma-ray strength functions and methods for calculating gamma emission in statistical model codes. The experimental GDR parameters are represented by Lorentzian fits to the photo-absorption cross sections for 102 nuclides ranging from {sup 51}V to {sup 239}Pu. FISSION includes global prescriptions for fission barriers and nuclear level densities at fission saddle points based on microscopic HFB calculations constrained by experimental fission cross sections.« less

Robust Level Coincidences in the Subband Structure of Quasi 2D Systems

NASA Astrophysics Data System (ADS)

Winkler, R.; Wang, L. Y.; Lin, Y. H.; Chu, C. S.

2011-03-01

Recently, level crossings in the energy bands of crystals have been identified as a key signature for topological phase transitions. In general, three independent parameters must be tuned appropriately to bring two quantum levels into degeneracy. Using realistic models we show that for Bloch electrons in a crystal the parameter space controlling the occurrence of level coincidences has a much richer structure than anticipated previously. In particular, we identify cases where level coincidences depend on only two independent parameters thus making the level coincidences robust, i.e., they cannot be removed by a small perturbation of the Hamiltonian compatible with the crystal symmetry. We consider HgTe/CdTe quantum wells as a specific example. (See arXiv:1011.xxxx) Work supported by Taiwan NSC (Contract No. 99-2112-M-009-006) and a MOE-ATU grant. Work at Argonne supported by DOE BES under Contract No. DE-AC02-06CH11357.

Precise Measurement of the Neutrino Mixing Parameter θ23 from Muon Neutrino Disappearance in an Off-Axis Beam

NASA Astrophysics Data System (ADS)

Abe, K.; Adam, J.; Aihara, H.; Akiri, T.; Andreopoulos, C.; Aoki, S.; Ariga, A.; Ariga, T.; Assylbekov, S.; Autiero, D.; Barbi, M.; Barker, G. J.; Barr, G.; Bass, M.; Batkiewicz, M.; Bay, F.; Bentham, S. W.; Berardi, V.; Berger, B. E.; Berkman, S.; Bertram, I.; Bhadra, S.; Blaszczyk, F. d. M.; Blondel, A.; Bojechko, C.; Bordoni, S.; Boyd, S. B.; Brailsford, D.; Bravar, A.; Bronner, C.; Buchanan, N.; Calland, R. G.; Caravaca Rodríguez, J.; Cartwright, S. L.; Castillo, R.; Catanesi, M. G.; Cervera, A.; Cherdack, D.; Christodoulou, G.; Clifton, A.; Coleman, J.; Coleman, S. J.; Collazuol, G.; Connolly, K.; Cremonesi, L.; Dabrowska, A.; Danko, I.; Das, R.; Davis, S.; de Perio, P.; De Rosa, G.; Dealtry, T.; Dennis, S. R.; Densham, C.; Di Lodovico, F.; Di Luise, S.; Drapier, O.; Duboyski, T.; Duffy, K.; Dufour, F.; Dumarchez, J.; Dytman, S.; Dziewiecki, M.; Emery, S.; Ereditato, A.; Escudero, L.; Finch, A. J.; Floetotto, L.; Friend, M.; Fujii, Y.; Fukuda, Y.; Furmanski, A. P.; Galymov, V.; Giffin, S.; Giganti, C.; Gilje, K.; Goeldi, D.; Golan, T.; Gonin, M.; Grant, N.; Gudin, D.; Hadley, D. R.; Haesler, A.; Haigh, M. D.; Hamilton, P.; Hansen, D.; Hara, T.; Hartz, M.; Hasegawa, T.; Hastings, N. C.; Hayato, Y.; Hearty, C.; Helmer, R. L.; Hierholzer, M.; Hignight, J.; Hillairet, A.; Himmel, A.; Hiraki, T.; Hirota, S.; Holeczek, J.; Horikawa, S.; Huang, K.; Ichikawa, A. K.; Ieki, K.; Ieva, M.; Ikeda, M.; Imber, J.; Insler, J.; Irvine, T. J.; Ishida, T.; Ishii, T.; Ives, S. J.; Iwai, E.; Iyogi, K.; Izmaylov, A.; Jacob, A.; Jamieson, B.; Johnson, R. A.; Jo, J. H.; Jonsson, P.; Jung, C. K.; Kabirnezhad, M.; Kaboth, A. C.; Kajita, T.; Kakuno, H.; Kameda, J.; Kanazawa, Y.; Karlen, D.; Karpikov, I.; Kearns, E.; Khabibullin, M.; Khotjantsev, A.; Kielczewska, D.; Kikawa, T.; Kilinski, A.; Kim, J.; Kisiel, J.; Kitching, P.; Kobayashi, T.; Koch, L.; Kolaceke, A.; Konaka, A.; Kormos, L. L.; Korzenev, A.; Koseki, K.; Koshio, Y.; Kreslo, I.; Kropp, W.; Kubo, H.; Kudenko, Y.; Kumaratunga, S.; Kurjata, R.; Kutter, T.; Lagoda, J.; Laihem, K.; Lamont, I.; Laveder, M.; Lawe, M.; Lazos, M.; Lee, K. P.; Lindner, T.; Lister, C.; Litchfield, R. P.; Longhin, A.; Ludovici, L.; Macaire, M.; Magaletti, L.; Mahn, K.; Malek, M.; Manly, S.; Marino, A. D.; Marteau, J.; Martin, J. F.; Maruyama, T.; Marzec, J.; Mathie, E. L.; Matveev, V.; Mavrokoridis, K.; Mazzucato, E.; McCarthy, M.; McCauley, N.; McFarland, K. S.; McGrew, C.; Metelko, C.; Mezzetto, M.; Mijakowski, P.; Miller, C. A.; Minamino, A.; Mineev, O.; Mine, S.; Missert, A.; Miura, M.; Monfregola, L.; Moriyama, S.; Mueller, Th. A.; Murakami, A.; Murdoch, M.; Murphy, S.; Myslik, J.; Nagasaki, T.; Nakadaira, T.; Nakahata, M.; Nakai, T.; Nakamura, K.; Nakayama, S.; Nakaya, T.; Nakayoshi, K.; Naples, D.; Nielsen, C.; Nirkko, M.; Nishikawa, K.; Nishimura, Y.; O'Keeffe, H. M.; Ohta, R.; Okumura, K.; Okusawa, T.; Oryszczak, W.; Oser, S. M.; Owen, R. A.; Oyama, Y.; Palladino, V.; Palomino, J.; Paolone, V.; Payne, D.; Perevozchikov, O.; Perkin, J. D.; Petrov, Y.; Pickard, L.; Pinzon Guerra, E. S.; Pistillo, C.; Plonski, P.; Poplawska, E.; Popov, B.; Posiadala, M.; Poutissou, J.-M.; Poutissou, R.; Przewlocki, P.; Quilain, B.; Radicioni, E.; Ratoff, P. N.; Ravonel, M.; Rayner, M. A. M.; Redij, A.; Reeves, M.; Reinherz-Aronis, E.; Retiere, F.; Robert, A.; Rodrigues, P. A.; Rojas, P.; Rondio, E.; Roth, S.; Rubbia, A.; Ruterbories, D.; Sacco, R.; Sakashita, K.; Sánchez, F.; Sato, F.; Scantamburlo, E.; Scholberg, K.; Schoppmann, S.; Schwehr, J.; Scott, M.; Seiya, Y.; Sekiguchi, T.; Sekiya, H.; Sgalaberna, D.; Shiozawa, M.; Short, S.; Shustrov, Y.; Sinclair, P.; Smith, B.; Smith, R. J.; Smy, M.; Sobczyk, J. T.; Sobel, H.; Sorel, M.; Southwell, L.; Stamoulis, P.; Steinmann, J.; Still, B.; Suda, Y.; Suzuki, A.; Suzuki, K.; Suzuki, S. Y.; Suzuki, Y.; Szeglowski, T.; Tacik, R.; Tada, M.; Takahashi, S.; Takeda, A.; Takeuchi, Y.; Tanaka, H. K.; Tanaka, H. A.; Tanaka, M. M.; Terhorst, D.; Terri, R.; Thompson, L. F.; Thorley, A.; Tobayama, S.; Toki, W.; Tomura, T.; Totsuka, Y.; Touramanis, C.; Tsukamoto, T.; Tzanov, M.; Uchida, Y.; Ueno, K.; Vacheret, A.; Vagins, M.; Vasseur, G.; Wachala, T.; Waldron, A. V.; Walter, C. W.; Wark, D.; Wascko, M. O.; Weber, A.; Wendell, R.; Wilkes, R. J.; Wilking, M. J.; Wilkinson, C.; Williamson, Z.; Wilson, J. R.; Wilson, R. J.; Wongjirad, T.; Yamada, Y.; Yamamoto, K.; Yanagisawa, C.; Yen, S.; Yershov, N.; Yokoyama, M.; Yuan, T.; Yu, M.; Zalewska, A.; Zalipska, J.; Zambelli, L.; Zaremba, K.; Ziembicki, M.; Zimmerman, E. D.; Zito, M.; Żmuda, J.; T2K Collaboration

2014-05-01

New data from the T2K neutrino oscillation experiment produce the most precise measurement of the neutrino mixing parameter θ23. Using an off-axis neutrino beam with a peak energy of 0.6 GeV and a data set corresponding to 6.57×1020 protons on target, T2K has fit the energy-dependent νμ oscillation probability to determine oscillation parameters. The 68% confidence limit on sin2(θ23) is 0.514-0.056+0.055 (0.511±0.055), assuming normal (inverted) mass hierarchy. The best-fit mass-squared splitting for normal hierarchy is Δm322=(2.51±0.10)×10-3 eV2/c4 (inverted hierarchy: Δm132=(2.48±0.10)×10-3 eV2/c4). Adding a model of multinucleon interactions that affect neutrino energy reconstruction is found to produce only small biases in neutrino oscillation parameter extraction at current levels of statistical uncertainty.

Evolution of non-interacting entropic dark energy and its phantom nature

NASA Astrophysics Data System (ADS)

Mathew, Titus K.; Murali, Chinthak; Shejeelammal, J.

2016-04-01

Assuming the form of the entropic dark energy (EDE) as it arises from the surface term in the Einstein-Hilbert’s action, its evolution was analyzed in an expanding flat universe. The model parameters were evaluated by constraining the model using the Union data on Type Ia supernovae. We found that in the non-interacting case, the model predicts an early decelerated phase and a later accelerated phase at the background level. The evolutions of the Hubble parameter, dark energy (DE) density, equation of state parameter and deceleration parameter were obtained. The model hardly seems to be supporting the linear perturbation growth for the structure formation. We also found that the EDE shows phantom nature for redshifts z < 0.257. During the phantom epoch, the model predicts big rip effect at which both the scale factor of expansion and the DE density become infinitely large and the big rip time is found to be around 36 Giga years from now.

Empirical valence bond models for reactive potential energy surfaces: a parallel multilevel genetic program approach.

PubMed

Bellucci, Michael A; Coker, David F

2011-07-28

We describe a new method for constructing empirical valence bond potential energy surfaces using a parallel multilevel genetic program (PMLGP). Genetic programs can be used to perform an efficient search through function space and parameter space to find the best functions and sets of parameters that fit energies obtained by ab initio electronic structure calculations. Building on the traditional genetic program approach, the PMLGP utilizes a hierarchy of genetic programming on two different levels. The lower level genetic programs are used to optimize coevolving populations in parallel while the higher level genetic program (HLGP) is used to optimize the genetic operator probabilities of the lower level genetic programs. The HLGP allows the algorithm to dynamically learn the mutation or combination of mutations that most effectively increase the fitness of the populations, causing a significant increase in the algorithm's accuracy and efficiency. The algorithm's accuracy and efficiency is tested against a standard parallel genetic program with a variety of one-dimensional test cases. Subsequently, the PMLGP is utilized to obtain an accurate empirical valence bond model for proton transfer in 3-hydroxy-gamma-pyrone in gas phase and protic solvent. © 2011 American Institute of Physics

Crystal field analysis of the energy level structure of Cs2NaAlF6:Cr3+

NASA Astrophysics Data System (ADS)

Rudowicz, C.; Brik, M. G.; Avram, N. M.; Yeung, Y. Y.; Gnutek, P.

2006-06-01

An analysis of the energy level structure of Cr3+ ions in Cs2NaAlF6 crystal is performed using the exchange charge model (ECM) together with the crystal field analysis/microscopic spin Hamiltonian (CFA/MSH) computer package. Utilizing the crystal structure data, our approach enables modelling of the crystal field parameters (CFPs) and thus the energy level structure for Cr3+ ions at the two crystallographically inequivalent sites in Cs2NaAlF6. Using the ECM initial adjustment procedure, the CFPs are calculated in the crystallographic axis system centred at the Cr3+ ion at each site. Additionally the CFPs are also calculated using the superposition model (SPM). The ECM and SPM predicted CFP values match very well. Consideration of the symmetry aspects for the so-obtained CFP datasets reveals that the latter axis system matches the symmetry-adapted axis system related directly to the six Cr-F bonds well. Using the ECM predicted CFPs as an input for the CFA/MSH package, the complete energy level schemes are calculated for Cr3+ ions at the two sites. Comparison of the theoretical results with the experimental spectroscopic data yields satisfactory agreement. Our results confirm that the actual symmetry at both impurity sites I and II in the Cs2NaAlF6:Cr3+ system is trigonal D3d. The ECM predicted CFPs may be used as the initial (starting) parameters for simulations and fittings of the energy levels for Cr3+ ions in structurally similar hosts.

Analysis of solar spectra in the middle ultraviolet and visible for atmospheric trace constituents measurements. [hydroxyl radicals

NASA Technical Reports Server (NTRS)

Goldman, A.

1980-01-01

Individual spectral line parameters including line positions, strengths, and intensities were generated for the sq Alpha Sigma - sq Chi Pi (0,0) band of OH, applicable to atmospheric and high temperatures. Energy levels and transition frequencies are calculated by numerically diagonalizing the Hamiltonian. Line strengths are calculated using the dipole matrix and eigenvectors derived from energy matrix diagonalization. The line strengths are compared to those calculated from previously published algebraic line strength formulas. Tables of line parameters are presented for 240 K and 4600 K.

The large amplitude motions of methylamine from the perspective of the highly correlated ab initio methods

NASA Astrophysics Data System (ADS)

Senent, M. L.

2018-01-01

CCSD(T)-F12 theory in connection with extended basis sets is employed to determine the electronic ground state spectroscopic parameters of methylamine at low temperatures. The geometry, the rotational constants, all the fundamental frequencies, the dipole moment and its components, and the centrifugal distortion constants, are provided. The ground vibrational state rotational constants were found to be A0 = 103067.15 MHz, B0 = 22588.29 MHz, and C0 = 21710.50 MHz and the dipole moment to be 1.4071D. Fermi displacements of the vibrational bands are predicted. The low vibrational energy levels corresponding to the large amplitude motions are determine variationally using a flexible three-dimensional model depending on three variables: the HNH bending, the NH2 wagging and the CH3 torsional coordinates. The computed levels are compared with previous experimental and calculated energies. Methylamine parameters are very sensitive to the level of ab initio calculations.

Density-Functional Theory with Dispersion-Correcting Potentials for Methane: Bridging the Efficiency and Accuracy Gap between High-Level Wave Function and Classical Molecular Mechanics Methods.

PubMed

Torres, Edmanuel; DiLabio, Gino A

2013-08-13

Large clusters of noncovalently bonded molecules can only be efficiently modeled by classical mechanics simulations. One prominent challenge associated with this approach is obtaining force-field parameters that accurately describe noncovalent interactions. High-level correlated wave function methods, such as CCSD(T), are capable of correctly predicting noncovalent interactions, and are widely used to produce reference data. However, high-level correlated methods are generally too computationally costly to generate the critical reference data required for good force-field parameter development. In this work we present an approach to generate Lennard-Jones force-field parameters to accurately account for noncovalent interactions. We propose the use of a computational step that is intermediate to CCSD(T) and classical molecular mechanics, that can bridge the accuracy and computational efficiency gap between them, and demonstrate the efficacy of our approach with methane clusters. On the basis of CCSD(T)-level binding energy data for a small set of methane clusters, we develop methane-specific, atom-centered, dispersion-correcting potentials (DCPs) for use with the PBE0 density-functional and 6-31+G(d,p) basis sets. We then use the PBE0-DCP approach to compute a detailed map of the interaction forces associated with the removal of a single methane molecule from a cluster of eight methane molecules and use this map to optimize the Lennard-Jones parameters for methane. The quality of the binding energies obtained by the Lennard-Jones parameters we obtained is assessed on a set of methane clusters containing from 2 to 40 molecules. Our Lennard-Jones parameters, used in combination with the intramolecular parameters of the CHARMM force field, are found to closely reproduce the results of our dispersion-corrected density-functional calculations. The approach outlined can be used to develop Lennard-Jones parameters for any kind of molecular system.

Effects of dietary energy levels on physiological parameters and reproductive performance of gestating sows over three consecutive parities.

PubMed

Jin, S S; Jin, Y H; Jang, J C; Hong, J S; Jung, S W; Kim, Y Y

2018-03-01

This experiment was to evaluate the effects of the dietary energy levels on the physiological parameters and reproductive performance during gestation over three parities in sows. A total of 52 F1 gilts (Yorkshire×Landrace) were allotted to one of four dietary treatments using a completely randomized design. The treatments contained 3,100, 3,200, 3,300, or 3,400 kcal of metabolizable energy (ME)/kg diet but feed was provided at 2.0, 2.2, and 2.4 kg/d in the first, second and third parity, respectively. The body weight and body weight gain during gestation increased as the dietary energy level increased (p<0.05, and p<0.01) in the first parity. In the second parity, the body weight of sows was the lowest (p<0.05) when 3,100 kcal of ME/kg treatment diet was provided. The body weight was higher as the dietary energy level increased (p<0.05) during the gestation period in the third parity. During lactation, the voluntary feed intake of lactating sows tended to decrease when gilts were fed higher energy treatment diet (p = 0.08) and the body weight, body weight gain were increased by dietary energy level during gestation (p< 0.05). Backfat thickness was not affected by dietary treatment during the gestation period in three parities, interestingly backfat change from breeding to d 110 of gestation was higher as the dietary energy level increased at the first parity (p<0.05). When gilts were fed 3,400 kcal of ME/kg treatment diet a higher number of weaning piglets was observed in the first parity (p<0.05). The highest culling rate (69%) was seen when gestating sows were fed 3,100 kcal/kg ME treatment diet during three parities. In conclusion, the adequate energy intake of gestating sows should be 6,400 or 6,600 kcal of ME/d, 7,040 or 7,260 kcal of ME/d, and 7,680 or 7,920 kcal of ME/d for parity 1, 2, and 3, respectively.

Development of EnergyPlus Utility to Batch Simulate Building Energy Performance on a National Scale

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

Valencia, Jayson F.; Dirks, James A.

2008-08-29

EnergyPlus is a simulation program that requires a large number of details to fully define and model a building. Hundreds or even thousands of lines in a text file are needed to run the EnergyPlus simulation depending on the size of the building. To manually create these files is a time consuming process that would not be practical when trying to create input files for thousands of buildings needed to simulate national building energy performance. To streamline the process needed to create the input files for EnergyPlus, two methods were created to work in conjunction with the National Renewable Energymore » Laboratory (NREL) Preprocessor; this reduced the hundreds of inputs needed to define a building in EnergyPlus to a small set of high-level parameters. The first method uses Java routines to perform all of the preprocessing on a Windows machine while the second method carries out all of the preprocessing on the Linux cluster by using an in-house built utility called Generalized Parametrics (GPARM). A comma delimited (CSV) input file is created to define the high-level parameters for any number of buildings. Each method then takes this CSV file and uses the data entered for each parameter to populate an extensible markup language (XML) file used by the NREL Preprocessor to automatically prepare EnergyPlus input data files (idf) using automatic building routines and macro templates. Using a Linux utility called “make”, the idf files can then be automatically run through the Linux cluster and the desired data from each building can be aggregated into one table to be analyzed. Creating a large number of EnergyPlus input files results in the ability to batch simulate building energy performance and scale the result to national energy consumption estimates.« less

The effect of vocal and instrumental music on cardio respiratory variables, energy expenditure and exertion levels during sub maximal treadmill exercise.

PubMed

Savitha, D; Sejil, T V; Rao, Shwetha; Roshan, C J; Roshan, C J

2013-01-01

The purpose of the study was to investigate the effect of vocal and instrumental music on various physiological parameters during submaximal exercise. Each subject underwent three sessions of exercise protocol without music, with vocal music, and instrumental versions of same piece of music. The protocol consisted of 10 min treadmill exercise at 70% HR(max) and 20 min of recovery. Minute to minute heart rate and breath by breath recording of respiratory parameters, rate of energy expenditure and perceived exertion levels were measured. Music, irrespective of the presence or absence of lyrics, enabled the subjects to exercise at a significantly lower heart rate and oxygen consumption, reduced the metabolic cost and perceived exertion levels of exercise (P < 0.05). There was faster recovery of systolic and diastolic blood pressures and exertion levels during the post exercise period. Music having a relaxant effect could have probably increased the parasympathetic activation leading to these effects.

Phenomenological model of nuclear primary air showers

NASA Technical Reports Server (NTRS)

Tompkins, D. R., Jr.; Saterlie, S. F.

1976-01-01

The development of proton primary air showers is described in terms of a model based on a hadron core plus an electromagnetic cascade. The muon component is neglected. The model uses three parameters: a rate at which hadron core energy is converted into electromagnetic cascade energy and a two-parameter sea-level shower-age function. By assuming an interaction length for the primary nucleus, the model is extended to nuclear primaries. Both models are applied over the energy range from 10 to the 13th power to 10 to the 21st power eV. Both models describe the size and age structure (neglecting muons) from a depth of 342 to 2052 g/sq cm.

The energy-level crossing behavior and quantum Fisher information in a quantum well with spin-orbit coupling

PubMed Central

Wang, Z. H.; Zheng, Q.; Wang, Xiaoguang; Li, Yong

2016-01-01

We study the energy-level crossing behavior in a two-dimensional quantum well with the Rashba and Dresselhaus spin-orbit couplings (SOCs). By mapping the SOC Hamiltonian onto an anisotropic Rabi model, we obtain the approximate ground state and its quantum Fisher information (QFI) via performing a unitary transformation. We find that the energy-level crossing can occur in the quantum well system within the available parameters rather than in cavity and circuit quantum eletrodynamics systems. Furthermore, the influence of two kinds of SOCs on the QFI is investigated and an intuitive explanation from the viewpoint of the stationary perturbation theory is given. PMID:26931762

The energy-level crossing behavior and quantum Fisher information in a quantum well with spin-orbit coupling.

PubMed

Wang, Z H; Zheng, Q; Wang, Xiaoguang; Li, Yong

2016-03-02

We study the energy-level crossing behavior in a two-dimensional quantum well with the Rashba and Dresselhaus spin-orbit couplings (SOCs). By mapping the SOC Hamiltonian onto an anisotropic Rabi model, we obtain the approximate ground state and its quantum Fisher information (QFI) via performing a unitary transformation. We find that the energy-level crossing can occur in the quantum well system within the available parameters rather than in cavity and circuit quantum eletrodynamics systems. Furthermore, the influence of two kinds of SOCs on the QFI is investigated and an intuitive explanation from the viewpoint of the stationary perturbation theory is given.

The energy-level crossing behavior and quantum Fisher information in a quantum well with spin-orbit coupling

NASA Astrophysics Data System (ADS)

Wang, Z. H.; Zheng, Q.; Wang, Xiaoguang; Li, Yong

2016-03-01

We study the energy-level crossing behavior in a two-dimensional quantum well with the Rashba and Dresselhaus spin-orbit couplings (SOCs). By mapping the SOC Hamiltonian onto an anisotropic Rabi model, we obtain the approximate ground state and its quantum Fisher information (QFI) via performing a unitary transformation. We find that the energy-level crossing can occur in the quantum well system within the available parameters rather than in cavity and circuit quantum eletrodynamics systems. Furthermore, the influence of two kinds of SOCs on the QFI is investigated and an intuitive explanation from the viewpoint of the stationary perturbation theory is given.

Radiation efficiency of earthquake sources at different hierarchical levels

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

Kocharyan, G. G., E-mail: gevorgkidg@mail.ru; Moscow Institute of Physics and Technology

Such factors as earthquake size and its mechanism define common trends in alteration of radiation efficiency. The macroscopic parameter that controls the efficiency of a seismic source is stiffness of fault or fracture. The regularities of this parameter alteration with scale define several hierarchical levels, within which earthquake characteristics obey different laws. Small variations of physical and mechanical properties of the fault principal slip zone can lead to dramatic differences both in the amplitude of released stress and in the amount of radiated energy.

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

Yoshii, Kazutomo; Llopis, Pablo; Zhang, Kaicheng

As CMOS scaling nears its end, parameter variations (process, temperature and voltage) are becoming a major concern. To overcome parameter variations and provide stability, modern processors are becoming dynamic, opportunistically adjusting voltage and frequency based on thermal and energy constraints, which negatively impacts traditional bulk-synchronous parallelism-minded hardware and software designs. As node-level architecture is growing in complexity, implementing variation control mechanisms only with hardware can be a challenging task. In this paper we investigate a software strategy to manage hardwareinduced variations, leveraging low-level monitoring/controlling mechanisms.

Effects of concentrate crude protein content on nutrient digestibility, energy utilization, and methane emissions in lactating dairy cows fed fresh-cut perennial grass.

PubMed

Hynes, D N; Stergiadis, S; Gordon, A; Yan, T

2016-11-01

Although many studies have investigated mitigation strategies for methane (CH 4 ) output from dairy cows fed a wide variety of diets, research on the effects of concentrate crude protein (CP) content on CH 4 emissions from dairy cows offered fresh grass is limited. The present study was designed to evaluate the effects of cow genotype and concentrate CP level on nutrient digestibility, energy utilization, and CH 4 emissions in dairy cows offered fresh-grass diets. Twelve multiparous lactating dairy cows (6 Holstein and 6 Holstein × Swedish Red) were blocked into 3 groups for each breed and assigned to a low-, medium-, or high-CP concentrate diet [14.1, 16.1, and 18.1% CP on a dry matter (DM) basis, respectively], in a 3-period changeover study (25d per period). Total diets contained (DM basis) 32.8% concentrates and 67.2% perennial ryegrass, which was harvested daily. All measurements were undertaken during the final 6d of each period: digestibility measurements for 6d and calorimetric measurements in respiration chambers for 3d. Feed intake and milk production data were reported in a previous paper. We observed no significant interaction between concentrate CP level and cow genotype on any parameter. Concentrate CP level had no significant effect on any energy utilization parameter, except for urinary energy output, which was positively related to concentrate CP level. Similarly, concentrate CP content had no effect on CH 4 emission (g/d), CH 4 per kg feed intake, or nutrient digestibility. Cross breeding of Holstein cows significantly reduced gross energy, digestible energy, and metabolizable energy intake, heat production, and milk energy output. However, cow genotype had no significant effect on energy utilization efficiency or CH 4 parameters. Furthermore, the present study yielded a value for gross energy lost as CH 4 (5.6%) on fresh grass-based diets that was lower than the widely accepted value of 6.5%. The present findings indicate that reducing concentrate CP content from 18.1 to 14.1% may not be a successful way of alleviating CH 4 emissions from lactating dairy cows offered good-quality fresh grass, but grazing cows could be offered a low-CP concentrate without compromising energy utilization efficiency. Further research is needed to investigate whether larger differences in dietary CP content may yield positive results. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Design and development of Building energy simulation Software for prefabricated cabin type of industrial building (PCES)

NASA Astrophysics Data System (ADS)

Zhang, Jun; Li, Ri Yi

2018-06-01

Building energy simulation is an important supporting tool for green building design and building energy consumption assessment, At present, Building energy simulation software can't meet the needs of energy consumption analysis and cabinet level micro environment control design of prefabricated building. thermal physical model of prefabricated building is proposed in this paper, based on the physical model, the energy consumption calculation software of prefabricated cabin building(PCES) is developed. we can achieve building parameter setting, energy consumption simulation and building thermal process and energy consumption analysis by PCES.

Properties of Energy Spectra of Molecular Crystals Investigated by Nonlinear Theory

NASA Astrophysics Data System (ADS)

Pang, Xiao-Feng; Zhang, Huai-Wu

We calculate the quantum energy spectra of molecular crystals, such as acetanilide, by using discrete nonlinear Schrodinger equation, containing various interactions, appropriate to the systems. The energy spectra consist of many energy bands, in each energy band there are a lot of energy levels including some higher excited states. The result of energy spectrum is basically consistent with experimental values obtained by infrared absorption and Raman scattering in acetanilide and can also explain some experimental results obtained by Careri et al. Finally, we further discuss the influences of variously characteristic parameters on the energy spectra of the systems.

Energy dissipation in the blade tip region of an axial fan

NASA Astrophysics Data System (ADS)

Bizjan, B.; Milavec, M.; Širok, B.; Trenc, F.; Hočevar, M.

2016-11-01

A study of velocity and pressure fluctuations in the tip clearance flow of an axial fan is presented in this paper. Two different rotor blade tip designs were investigated: the standard one with straight blade tips and the modified one with swept-back tip winglets. Comparison of integral sound parameters indicates a significant noise level reduction for the modified blade tip design. To study the underlying mechanisms of the energy conversion and noise generation, a novel experimental method based on simultaneous measurements of local flow velocity and pressure has also been developed and is presented here. The method is based on the phase space analysis by the use of attractors, which enable more accurate identification and determination of the local flow structures and turbulent flow properties. Specific gap flow energy derived from the pressure and velocity time series was introduced as an additional attractor parameter to assess the flow energy distribution and dissipation within the phase space, and thus determines characteristic sources of the fan acoustic emission. The attractors reveal a more efficient conversion of the pressure to kinetic flow energy in the case of the modified (tip winglet) fan blade design, and also a reduction in emitted noise levels. The findings of the attractor analysis are in a good agreement with integral fan characteristics (efficiency and noise level), while offering a much more accurate and detailed representation of gap flow phenomena.

Analytic functions for potential energy curves, dipole moments, and transition dipole moments of LiRb molecule.

PubMed

You, Yang; Yang, Chuan-Lu; Wang, Mei-Shan; Ma, Xiao-Guang; Liu, Wen-Wang; Wang, Li-Zhi

2016-01-15

The analytic potential energy functions (APEFs) of the X(1)Σ(+), 2(1)Σ(+), a(3)Σ(+), and 2(3)Σ(+) states of the LiRb molecule are obtained using Morse long-range potential energy function with damping function and nonlinear least-squares method. These calculations were based on the potential energy curves (PECs) calculated using the multi-reference configuration interaction (MRCI) method. The reliability of the APEFs is confirmed using the curves of their first and second derivatives. By using the obtained APEFs, the rotational and vibrational energy levels of the states are determined by solving the Schrödinger equation of nuclear movement. The spectroscopic parameters, which are deduced using Dunham expansion, and the obtained rotational and vibrational levels are compared with the reported theoretical and experimental values. The correlation effect of the electrons of the inner shell remarkably improves the results compared with the experimental spectroscopic parameters. For the first time, the APEFs for the dipole moments and transition dipole moments of the states have been determined based on the curves obtained from the MRCI calculations. Copyright © 2015 Elsevier B.V. All rights reserved.

Microleakage in Class V cavities with self-etching adhesive system and conventional rotatory or laser Er,Cr:YSGG

PubMed Central

Arnabat, J; España-Tost, T

2012-01-01

Objective: To analyse microleakage in Class V cavity preparation with Er;Cr:YSGG at different parameters using a self-etching adhesive system. Background: Several studies reported microleakage around composite restorations when cavity preparation is done or treated by Er;Cr:YSGG laser. We want to compare different energy densities in order to obtain the best parameters, when using a self-etching adhesive system. Methods: A class V preparations was performed in 120 samples of human teeth were divided in 3 groups: (1) Preparation using the burr. (2) Er;Cr:YSGG laser preparation with high energy 4W, 30 Hz, 50% Water 50% Air and (3) Er;Cr:YSGG laser preparation lower energy 1.5 W, 30 Hz, 30% Water 30% Air. All the samples were restored with self-etching adhesive system and hybrid composite. Thermocycling (5000 cycles) and immersed in 0.5% fuchsin. The restorations were sectioned and evaluated the microleakage with a stereomicroscope. Results: Lower energy laser used for preparation showed significant differences in enamel and dentin. To group 3, the microleakage in the enamel was less, whilst the group 1, treated with the turbine, showed less microleakage at dentin level. Group 2 showed the highest microleakage at dentin/cement level. Conclusion: Burr preparation gives the lowest microleakage at cement/dentin level, whilst Er;Cr:YSGG laser at lower power has the low energy obtains lowest microleakage at enamel. On the contrary high-energy settings produce inferior results in terms of microleakage. PMID:24511195

Microscopic study of spin cut-off factors of nuclear level densities

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

Gholami, M.; Kildir, M.; Behkami, A. N.

Level densities and spin cut-off factors have been investigated within the microscopic approach based on the BCS Hamiltonian. In particular, the spin cut-off parameters have been calculated at neutron binding energies over a large range of nuclear mass using the BCS theory. The spin cut-off parameters {sigma}{sup 2}(E) have also been obtained from the Gilbert and Cameron expression and from rigid body calculations. The results were compared with their corresponding macroscopic values. It was found that the values of {sigma}{sup 2}(E) did not increase smoothly with A as expected based on macroscopic theory. Instead, the values of {sigma}{sup 2}(E) showmore » structure reflecting the angular momentum of the shell model orbitals near the Fermi energy.« less

Study of the statistical physics bases on superstatistics from the β-fluctuated to the T-fluctuated form

NASA Astrophysics Data System (ADS)

Sargolzaeipor, S.; Hassanabadi, H.; Chung, W. S.

2018-04-01

In this paper, we study the T -fluctuated form of superstatistics. In this form, some thermodynamic quantities such as the Helmholtz energy, the entropy and the internal energy, are expressed in terms of the T -fluctuated form for a canonical ensemble. In addition, the partition functions in the formalism for 2-level and 3-level distributions are derived. Then we make use of the T -fluctuated superstatistics for a quantum harmonic oscillator problem and the thermal properties of the system for three statistics of the Bose-Einstein, Maxwell-Boltzmann and Fermi-Dirac statistics are calculated. The effect of the deformation parameter on these properties is examined. All the results recover the well-known results by removing the deformation parameter.

Influence of the ordering of impurities on the appearance of an energy gap and on the electrical conductance of graphene.

PubMed

Repetsky, S P; Vyshyvana, I G; Kruchinin, S P; Bellucci, Stefano

2018-06-14

In the one-band model of strong coupling, the influence of substitutional impurity atoms on the energy spectrum and electrical conductance of graphene is studied. It is established that the ordering of substitutional impurity atoms on nodes of the crystal lattice causes the appearance of a gap in the energy spectrum of graphene with width η|δ| centered at the point yδ, where η is the parameter of ordering, δ is the difference of the scattering potentials of impurity atoms and carbon atoms, and y is the impurity concentration. The maximum value of the parameter of ordering is [Formula: see text]. For the complete ordering of impurity atoms, the energy gap width equals [Formula: see text]. If the Fermi level falls in the region of the mentioned gap, then the electrical conductance [Formula: see text] at the ordering of graphene, i.e., the metal-dielectric transition arises. If the Fermi level is located outside the gap, then the electrical conductance increases with the parameter of order η by the relation [Formula: see text]. At the concentration [Formula: see text], as the ordering of impurity atoms η →1, the electrical conductance of graphene [Formula: see text], i.e., the transition of graphene in the state of ideal electrical conductance arises.

Theoretical study on the antitumor properties of Ru(II) complexes containing 2-pyridyl, 2-pyridine-4-carboxylic acid ligands

NASA Astrophysics Data System (ADS)

Erkan kariper, Sultan; Sayin, Koray; Karakaş, Duran

2017-12-01

[Ru(bipy)2(CppH)]2+(1), [Ru(bipy)2(Cpp-NH-Hex-COOH)]2+(2), [Ru(dppz)2(CppH)]2+(3) and [Ru(dppz)2(Cpp-NH-Hex-COOH)]2+(4) were calculated by Hartree-Fock (HF), Density Functional Theory (DFT) hybrid B3LYP and Moller-Plesset Perturbation (MPn n = 2,3) theory method and CEP-4G, CEP-31G, CEP-121G, LANL2DZ, LANL2MB, SDD basic sets and a mixed basic set with the keyword GEN in gas phase and water. Structure parameters obtained from optimized structures were compared with experimental parameters. M062X/(6-31G(d))(CEP-4G) level was taken into account for the most appropriate calculation level. IR, UV-VIS and NMR spectrums were examined for structural characterization. The optimal structure was identified via structure parameters, IR, UV-VIS and NMR spectrums. For the most compatible structure, the highest molecular orbital energy (EHOMO) which one of the most effective chemical determiners on the antitumor activity of the complexes, the lowest molecular orbital energy (ELUMO), LUMO-HOMO energy gap, hardness (η), softness (σ), electronegativity (χ), chemical potential (μ), electrophilicity index (ω), molar volume (V), dipole moment (DM), total negative charge (TNC), enthalpy (H), entropy (S) and total energy (E) were calculated. The causes of anticancer activity of the complexes have been studied.

Determination of interfacial states in solid heterostructures using a variable-energy positron beam

DOEpatents

Asoka kumar, Palakkal P. V.; Lynn, Kelvin G.

1993-01-01

A method and means is provided for characterizing interfacial electron states in solid heterostructures using a variable energy positron beam to probe the solid heterostructure. The method includes the steps of directing a positron beam having a selected energy level at a point on the solid heterostructure so that the positron beam penetrates into the solid heterostructure and causes positrons to collide with the electrons at an interface of the solid heterostructure. The number and energy of gamma rays emitted from the solid heterostructure as a result of the annihilation of positrons with electrons at the interface are detected. The data is quantified as a function of the Doppler broadening of the photopeak about the 511 keV line created by the annihilation of the positrons and electrons at the interface, preferably, as an S-parameter function; and a normalized S-parameter function of the data is obtained. The function of data obtained is compared with a corresponding function of the Doppler broadening of the annihilation photopeak about 511 keV for a positron beam having a second energy level directed at the same material making up a portion of the solid heterostructure. The comparison of these functions facilitates characterization of the interfacial states of electrons in the solid heterostructure at points corresponding to the penetration of positrons having the particular energy levels into the interface of the solid heterostructure. Accordingly, the invention provides a variable-energy non-destructive probe of solid heterostructures, such as SiO.sub.2 /Si, MOS or other semiconductor devices.

Determination of interfacial states in solid heterostructures using a variable-energy positron beam

DOEpatents

Asokakumar, P.P.V.; Lynn, K.G.

1993-04-06

A method and means is provided for characterizing interfacial electron states in solid heterostructures using a variable energy positron beam to probe the solid heterostructure. The method includes the steps of directing a positron beam having a selected energy level at a point on the solid heterostructure so that the positron beam penetrates into the solid heterostructure and causes positrons to collide with the electrons at an interface of the solid heterostructure. The number and energy of gamma rays emitted from the solid heterostructure as a result of the annihilation of positrons with electrons at the interface are detected. The data is quantified as a function of the Doppler broadening of the photopeak about the 511 keV line created by the annihilation of the positrons and electrons at the interface, preferably, as an S-parameter function; and a normalized S-parameter function of the data is obtained. The function of data obtained is compared with a corresponding function of the Doppler broadening of the annihilation photopeak about 511 keV for a positron beam having a second energy level directed at the same material making up a portion of the solid heterostructure. The comparison of these functions facilitates characterization of the interfacial states of electrons in the solid heterostructure at points corresponding to the penetration of positrons having the particular energy levels into the interface of the solid heterostructure. Accordingly, the invention provides a variable-energy non-destructive probe of solid heterostructures, such as SiO[sub 2]/Si, MOS or other semiconductor devices.

Self consistent solution of Schrödinger Poisson equations and some electronic properties of ZnMgO/ZnO hetero structures

NASA Astrophysics Data System (ADS)

Uslu, Salih; Yarar, Zeki

2017-02-01

The epitaxial growth of quantum wells composed of high quality allows the production and application to their device of new structures in low dimensions. The potential profile at the junction is determined by free carriers and by the level of doping. Therefore, the shape of potential is obtained by the electron density. Energy level determines the number of electrons that can be occupied at every level. Energy levels and electron density values of each level must be calculated self consistently. Starting with V(z) test potential, wave functions and electron densities for each energy levels can be calculated to solve Schrödinger equation. If Poisson's equation is solved with the calculated electron density, the electrostatic potential can be obtained. The new V(z) potential can be calculated with using electrostatic potential found beforehand. Thus, the obtained values are calculated self consistently to a certain error criterion. In this study, the energy levels formed in the interfacial potential, electron density in each level and the wave function dependence of material parameters were investigated self consistently.

Nuclear shape evolution based on microscopic level densities

DOE PAGES

Ward, D. E.; Carlsson, B. G.; Døssing, T.; ...

2017-02-27

Here, by combining microscopically calculated level densities with the Metropolis walk method, we develop a consistent framework for treating the energy and angular-momentum dependence of the nuclear shape evolution in the fission process. For each nucleus under consideration, the level density is calculated microscopically for each of more than five million shapes with a recently developed combinatorial method. The method employs the same single-particle levels as those used for the extraction of the pairing and shell contributions to the macroscopic-microscopic deformation-energy surface. Containing no new parameters, the treatment is suitable for elucidating the energy dependence of the dynamics of warmmore » nuclei on pairing and shell effects. It is illustrated for the fission fragment mass distribution for several uranium and plutonium isotopes of particular interest.« less

Electrically controlled crossing of energy levels in quantum dots in two-dimensional topological insulators

NASA Astrophysics Data System (ADS)

Sukhanov, Aleksei A.

2017-05-01

We study the energy spectra of bound states in quantum dots (QDs) formed by an electrostatic potential in two-dimensional topological insulator (TI) and their transformation with changes in QD depth and radius. It is found that, unlike a trivial insulator, the energy difference between the levels of the ground state and first excited state can decrease with decreasing the radius and increasing the depth of the QD so that these levels intersect under some critical condition. The crossing of the levels results in unusual features of optical properties caused by intraceneter electron transitions. In particular, it leads to significant changes of light absorption due to electron transitions between such levels and to the transient electroluminescence induced by electrical tuning of QD and TI parameters. In the case of magnetic TIs, the polarization direction of the absorbed or emitted circularly polarized light is changed due to the level crossing.

Actuation of an Inertia-Coupled Rimless Wheel Model across Level Ground

NASA Astrophysics Data System (ADS)

Weeks, Seth Caleb

The inertia-coupled rimless wheel model is a passive dynamic walking device which is theoretically capable of achieving highly efficient motion with no energy losses. Under non-ideal circumstances, energy losses due to air drag require the use of actuation to maintain stable motions. The Actuated Inertia-coupled Rimless Wheel Across Flat Terrain (AIRWAFT) model provides actuation to an inertia-coupled rimless wheel model across level ground to compensate for energy losses by applying hip-torque between the frame and inertia wheel via a motor. Two methods of defining the open-loop actuation are presented. Position control defines the relative position of the drum relative to the frame. Torque control specifies the amount of torque between the frame and the drum. The performance of the model was evaluated with respect to changes in various geometrical and control parameters and initial conditions. This parameter study led to the discovery of a stable, periodic motion with a cost of transport of 0.33.

Laser induced fluorescence of BaS: Sm phosphor and energy level splitting of Sm 3+ ion

NASA Astrophysics Data System (ADS)

Thomas, Reethamma; Nampoori, V. P. N.

1990-03-01

Fluorescence of BaS: Sm phosphor has been studied using a pulsed Nitrogen laser (337.1 nm) as the excitation source. The spectrum consists of a broad band in the region 540-660nm superposed by the characteristic Sm 3+ lines. Energy level splitting pattern of Sm 3+ due to crystal field effects has been calculated and relevent field parameters are evaluated. Analysis shows that Sm 3+ takes up Ba 2+ substitutional sites.

A quantitative analysis of household energy consumption in rural west Java: with particular emphasis on socio-economic influences

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

Hadi, S.S.

1982-01-01

A survey was conducted to estimate per capita, per household, and total energy consumption by region, by level of development, and by fuel source in rural West Java. Socio-economic conditions were also measured by using parameters that included income, family size, husband education, wife education, biomass fuelstock, level of village development, and land size. These data are tabulated and used to develop a model that can predict probabilities of fuel use, consumption, and variety.

Relationship between electronic properties and drug activity of seven quinoxaline compounds: A DFT study

NASA Astrophysics Data System (ADS)

Behzadi, Hadi; Roonasi, Payman; Assle taghipour, Khatoon; van der Spoel, David; Manzetti, Sergio

2015-07-01

The quantum chemical calculations at the DFT/B3LYP level of theory were carried out on seven quinoxaline compounds, which have been synthesized as anti-Mycobacterium tuberculosis agents. Three conformers were optimized for each compound and the lowest energy structure was found and used in further calculations. The electronic properties including EHOMO, ELUMO and related parameters as well as electron density around oxygen and nitrogen atoms were calculated for each compound. The relationship between the calculated electronic parameters and biological activity of the studied compounds were investigated. Six similar quinoxaline derivatives with possible more drug activity were suggested based on the calculated electronic descriptors. A mechanism was proposed and discussed based on the calculated electronic parameters and bond dissociation energies.

An analytical coarse-graining method which preserves the free energy, structural correlations, and thermodynamic state of polymer melts from the atomistic to the mesoscale.

PubMed

McCarty, J; Clark, A J; Copperman, J; Guenza, M G

2014-05-28

Structural and thermodynamic consistency of coarse-graining models across multiple length scales is essential for the predictive role of multi-scale modeling and molecular dynamic simulations that use mesoscale descriptions. Our approach is a coarse-grained model based on integral equation theory, which can represent polymer chains at variable levels of chemical details. The model is analytical and depends on molecular and thermodynamic parameters of the system under study, as well as on the direct correlation function in the k → 0 limit, c0. A numerical solution to the PRISM integral equations is used to determine c0, by adjusting the value of the effective hard sphere diameter, dHS, to agree with the predicted equation of state. This single quantity parameterizes the coarse-grained potential, which is used to perform mesoscale simulations that are directly compared with atomistic-level simulations of the same system. We test our coarse-graining formalism by comparing structural correlations, isothermal compressibility, equation of state, Helmholtz and Gibbs free energies, and potential energy and entropy using both united atom and coarse-grained descriptions. We find quantitative agreement between the analytical formalism for the thermodynamic properties, and the results of Molecular Dynamics simulations, independent of the chosen level of representation. In the mesoscale description, the potential energy of the soft-particle interaction becomes a free energy in the coarse-grained coordinates which preserves the excess free energy from an ideal gas across all levels of description. The structural consistency between the united-atom and mesoscale descriptions means the relative entropy between descriptions has been minimized without any variational optimization parameters. The approach is general and applicable to any polymeric system in different thermodynamic conditions.

The differential impact of low-carbon technologies on climate change mitigation cost under a range of socioeconomic and climate policy scenarios.

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

Barron, Robert W.; McJeon, Haewon C.

2015-05-01

This paper considers the effect of several key parameters of low carbon energy technologies on the cost of abatement. A methodology for determining the minimum level of performance required for a parameter to have a statistically significant impact on CO2 abatement cost is developed and used to evaluate the impact of eight key parameters of low carbon energy supply technologies on the cost of CO2 abatement. The capital cost of nuclear technology is found to have the greatest impact of the parameters studied. The cost of biomass and CCS technologies also have impacts, while their efficiencies have little, if any.more » Sensitivity analysis of the results with respect to population, GDP, and CO2 emission constraint show that the minimum performance level and impact of nuclear technologies is consistent across the socioeconomic scenarios studied, while the other technology parameters show different performance under higher population, lower GDP scenarios. Solar technology was found to have a small impact, and then only at very low costs. These results indicate that the cost of nuclear is the single most important driver of abatement cost, and that trading efficiency for cost may make biomass and CCS technologies more competitive.« less

Feasibility of dual-energy computed tomography in radiation therapy planning

NASA Astrophysics Data System (ADS)

Sheen, Heesoon; Shin, Han-Back; Cho, Sungkoo; Cho, Junsang; Han, Youngyih

2017-12-01

In this study, the noise level, effective atomic number ( Z eff), accuracy of the computed tomography (CT) number, and the CT number to the relative electron density EDconversion curve were estimated for virtual monochromatic energy and polychromatic energy. These values were compared to the theoretically predicted values to investigate the feasibility of the use of dual-energy CT in routine radiation therapy planning. The accuracies of the parameters were within the range of acceptability. These results can serve as a stepping stone toward the routine use of dual-energy CT in radiotherapy planning.

On ballistic parameters of less lethal projectiles influencing the severity of thoracic blunt impacts.

PubMed

Pavier, Julien; Langlet, André; Eches, Nicolas; Jacquet, Jean-François

2015-01-01

The development and safety certification of less lethal projectiles require an understanding of the influence of projectile parameters on projectile-chest interaction and on the resulting terminal effect. Several energy-based criteria have been developed for chest injury assessment. Many studies consider kinetic energy (KE) or energy density as the only projectile parameter influencing terminal effect. In a common KE range (100-160 J), analysis of the firing tests of two 40 mm projectiles of different masses on animal surrogates has been made in order to investigate the severity of the injuries in the thoracic region. Experimental results have shown that KE and calibre are not sufficient to discriminate between the two projectiles as regards their injury potential. Parameters, such as momentum, shape and impedance, influence the projectile-chest interaction and terminal effect. A simplified finite element model of projectile-structure interaction confirms the experimental tendencies. Within the range of ballistic parameters used, it has been demonstrated that maximum thoracic deflection is a useful parameter to predict the skeletal level of injury, and it largely depends on the projectile pre-impact momentum. However, numerical simulations show that these results are merely valid for the experimental conditions used and cannot be generalised. Nevertheless, the transmitted impulse seems to be a more general factor governing the thorax deflection.

Effect of seabuckthorn leaf extracts on circulating energy fuels, lipid peroxidation and antioxidant parameters in rats during exposure to cold, hypoxia and restraint (C-H-R) stress and post stress recovery.

PubMed

Saggu, Shalini; Kumar, Ratan

2008-06-01

The present study was carried out to study mechanism of adaptogenic activity of seabuckthorn leaf extract, administered orally in rats both in single and five doses at a dose of 100mg/kg body weight 30min prior to C-H-R exposure. The efficacy of the extract was studied on circulating energy fuels, lipid peroxidation and anti-oxidant parameters in rats on attaining the T(rec) 23 degrees C during C-H-R exposure and after recovery (T(rec) 37 degrees C) from C-H-R induced hypothermia. Single dose treatment in rats restricted rise in blood malondialdehyde (MDA) levels and decrease in glutathione (GSH) and catalase (CAT) levels. Both single and five doses also restricted the rise in serum free fatty acids (FFA) and lactate dehydrogenase (LDH) levels on attaining T(rec) 23 degrees C during C-H-R exposure, suggesting more efficient utilization of FFA for energy production and better maintained cell membrane permeability. This suggested that the adaptogenic activity of the extract might be due to its anti-oxidative activity, maintained blood glucose levels, better utilization of FFA and improved cell membrane permeability.

Thermal and magnetic properties of electron gas in toroidal quantum dot

NASA Astrophysics Data System (ADS)

Baghdasaryan, D. A.; Hayrapetyan, D. B.; Kazaryan, E. M.; Sarkisyan, H. A.

2018-07-01

One-electron states in a toroidal quantum dot in the presence of an external magnetic field have been considered. The magnetic field operator and the Schrodinger equation have been written in toroidal coordinates. The dependence of one-electron energy spectrum and wave function on the geometrical parameters of a toroidal quantum dot and magnetic field strength have been studied. The energy levels are employed to calculate the canonical partition function, which in its turn is used to obtain mean energy, heat capacity, entropy, magnetization, and susceptibility of noninteracting electron gas. The possibility to control the thermodynamic and magnetic properties of the noninteracting electron gas via changing the geometric parameters of the QD, magnetic field, and temperature, was demonstrated.

Parameter constraints from weak-lensing tomography of galaxy shapes and cosmic microwave background fluctuations

NASA Astrophysics Data System (ADS)

Merkel, Philipp M.; Schäfer, Björn Malte

2017-08-01

Recently, it has been shown that cross-correlating cosmic microwave background (CMB) lensing and three-dimensional (3D) cosmic shear allows to considerably tighten cosmological parameter constraints. We investigate whether similar improvement can be achieved in a conventional tomographic setup. We present Fisher parameter forecasts for a Euclid-like galaxy survey in combination with different ongoing and forthcoming CMB experiments. In contrast to a fully 3D analysis, we find only marginal improvement. Assuming Planck-like CMB data, we show that including the full covariance of the combined CMB and cosmic shear data improves the dark energy figure of merit (FOM) by only 3 per cent. The marginalized error on the sum of neutrino masses is reduced at the same level. For a next generation CMB satellite mission such as Prism, the predicted improvement of the dark energy FOM amounts to approximately 25 per cent. Furthermore, we show that the small improvement is contrasted by an increased bias in the dark energy parameters when the intrinsic alignment of galaxies is not correctly accounted for in the full covariance matrix.

Investigation of epi-thermal shape-parameter needed for precision analysis of activation

NASA Astrophysics Data System (ADS)

Elmaghraby, Elsayed K.

2017-06-01

The present work aims to expose factors that alter the isotope's effective resonance energy and its resonance integral in order to have consistency between the experimental observation of integral experiments and the prediction of the reaction rate. The investigation is based on disclosing the interference among resonances in Breit-Wigner and Reich-Moore representations to make the investigation of the statistical nature of resonances possible. The shape-parameter influence on the isotope's behavior in epi-thermal neutron field was investigated in the range from -0.1 to 0.1. Evaluated resonance data given in Evaluated Nuclear Data Files (ENDF/B VII.1) and temperature-dependent cross-sections of Point2015 are used. Only resolved resonances are considered in the present assessment. Tabulated values of resonance integrals and effective resonance energies with their moments are given for the majority of ENDF's isotopes. The reported data can be used, directly, to compute the integral parameters for any value of shape-parameter without the need to use numerical software tools. Correlations among effective resonance energy, experimental level spacing and resonance integral are discussed.

Pure MW Data for v=0-6 of PbI Give Vibrational Spacings and a Full Analytic Potential Energy Function

NASA Astrophysics Data System (ADS)

Yoo, Ji Ho (Chris); Evans, Corey; Walker, Nick; Le Roy, Robert J.

2015-06-01

At last year's ISMS meeting, Zaleski et al. reported new broadband MW spectroscopy measurements of pure rotational transitions in the v=0-6 levels of the ^2Π1/2 ground electronic state of PbI. The analysis presented at that time was a conventional v-level by v-level `band-constant' analysis performed using the PGopher program. That level-by-level PGopher analysis yielded values of B_v, D_v and five spin-splitting parameters for each vibrational level of each isotopologue. Ignoring the spin-splitting information, the B_v and D_v values were used to generate a set of synthetic pure R(0) transitions for each level that were taken to represent the ``mechanical'' information about the molecule contained in these spectra. A standard direct-potential-fit (DPF) analysis was then used to fit these data to an ``Expanded Morse Oscillator'' (EMO) potential function form. The well-depth parameter D_e was fixed at the literature value, while values of the equilibrium distance r_e and three EMO exponent-coefficient expansion `potential shape' parameters are determined from the fits. The best fits to the data yield potentials whose fundamental vibrational spacings are in excellent agreement with experiment together with reliable predictions for the first five overtone energies. D.P. Zaleski, H. Köckert, S.L. Stephens, N. Walker, L.-M. Dickens, and C. Evans, paper RE08 at the 69th International Symposium on Molecular Spectroscopy, University of Illinois (2014). PGopher - a Program for Simulating Rotational Structure, C. M. Western, University of Bristol, http://pgopher.chm.bris.ac.uk DPotFit 2.0: A Computer Program for fitting Diatomic Molecule Spectra to Potential Energy Functions, R.J. Le Roy, J. Seto and Y. Huang, University of Waterloo Chemical Physics Research Report CP-667 (2013); see http://leroy.uwaterloo.ca/programs/. K. Ziebarth, R. Breidohr, O. Shestakov and E.H. Fink, Chem. Phys. Lett. 190, 271 (1992).

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

Dale, R.; Sáez, D., E-mail: rdale@umh.es, E-mail: diego.saez@uv.es

The vector-tensor (VT) theory of gravitation revisited in this article was studied in previous papers, where it was proved that VT works and deserves attention. New observational data and numerical codes have motivated further development which is presented here. New research has been planed with the essential aim of proving that current cosmological observations, including Planck data, baryon acoustic oscillations (BAO), and so on, may be explained with VT, a theory which accounts for a kind of dark energy which has the same equation of state as vacuum. New versions of the codes CAMB and COSMOMC have been designed formore » applications to VT, and the resulting versions have been used to get the cosmological parameters of the VT model at suitable confidence levels. The parameters to be estimated are the same as in general relativity (GR), plus a new parameter D . For D = 0, VT linear cosmological perturbations reduces to those of GR, but the VT background may explain dark energy. The fits between observations and VT predictions lead to non vanishing | D | upper limits at the 1σ confidence level. The value D = 0 is admissible at this level, but this value is not that of the best fit in any case. Results strongly suggest that VT may explain current observations, at least, as well as GR; with the advantage that, as it is proved in this paper, VT has an additional parameter which facilitates adjustments to current observational data.« less

Hidden Order as a Source of Interface Superconductivity

NASA Astrophysics Data System (ADS)

Moor, Andreas; Volkov, Anatoly; Efetov, Konstantin

2015-03-01

We propose a new mechanism of the interfacial superconductivity observed in many heterostructures composed of different materials including high-temperature superconductors. Our proposal is based on the use of the Ginzburg-Landau equations applicable to a wide class of systems. The system under consideration is assumed to have, alongside the superconducting order parameter, also another competing order that might be a charge- or spin-density wave. At certain temperatures or doping level the superconducting state is not realized (thus, ``hidden''), while the amplitude of another order parameter corresponds to a minimum of the free energy. We also assume that at an interface or at a defect, the non-superconducting order parameter is suppressed (strongly or weakly), e.g., due to an enhanced impurity scattering. The local superconductivity is shown to emerge at the interface, and the spatial dependence of the corresponding order parameter is described by the Gross-Pitaevskii equation. The quantized values of the temperature and doping levels, at which Δ (x) arises, are determined by the ``energy'' levels of the linearized Gross-Pitaevskii equation, i.e., of the Schrodinger equation. Interestingly, the local superconductivity arises even at a small suppression of the rival order. We appreciate the support from DFG via the Projekt EF 11/8-1; K. B. E. gratefully acknowledges the financial support of the Ministry of Education and Science of the Russian Federation in the framework of Increase Competitiveness Program of NUST ``MISiS.''

Parameterization of DFTB3/3OB for Sulfur and Phosphorus for Chemical and Biological Applications

PubMed Central

2015-01-01

We report the parametrization of the approximate density functional tight binding method, DFTB3, for sulfur and phosphorus. The parametrization is done in a framework consistent with our previous 3OB set established for O, N, C, and H, thus the resulting parameters can be used to describe a broad set of organic and biologically relevant molecules. The 3d orbitals are included in the parametrization, and the electronic parameters are chosen to minimize errors in the atomization energies. The parameters are tested using a fairly diverse set of molecules of biological relevance, focusing on the geometries, reaction energies, proton affinities, and hydrogen bonding interactions of these molecules; vibrational frequencies are also examined, although less systematically. The results of DFTB3/3OB are compared to those from DFT (B3LYP and PBE), ab initio (MP2, G3B3), and several popular semiempirical methods (PM6 and PDDG), as well as predictions of DFTB3 with the older parametrization (the MIO set). In general, DFTB3/3OB is a major improvement over the previous parametrization (DFTB3/MIO), and for the majority cases tested here, it also outperforms PM6 and PDDG, especially for structural properties, vibrational frequencies, hydrogen bonding interactions, and proton affinities. For reaction energies, DFTB3/3OB exhibits major improvement over DFTB3/MIO, due mainly to significant reduction of errors in atomization energies; compared to PM6 and PDDG, DFTB3/3OB also generally performs better, although the magnitude of improvement is more modest. Compared to high-level calculations, DFTB3/3OB is most successful at predicting geometries; larger errors are found in the energies, although the results can be greatly improved by computing single point energies at a high level with DFTB3 geometries. There are several remaining issues with the DFTB3/3OB approach, most notably its difficulty in describing phosphate hydrolysis reactions involving a change in the coordination number of the phosphorus, for which a specific parametrization (3OB/OPhyd) is developed as a temporary solution; this suggests that the current DFTB3 methodology has limited transferability for complex phosphorus chemistry at the level of accuracy required for detailed mechanistic investigations. Therefore, fundamental improvements in the DFTB3 methodology are needed for a reliable method that describes phosphorus chemistry without ad hoc parameters. Nevertheless, DFTB3/3OB is expected to be a competitive QM method in QM/MM calculations for studying phosphorus/sulfur chemistry in condensed phase systems, especially as a low-level method that drives the sampling in a dual-level QM/MM framework. PMID:24803865

An Evaluation of the Potential for Shifting of Freight from Truck to Rail and Its Impacts on Energy Use and GHG Emissions

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

Zhou, Yan; Vyas, Anant D.; Guo, Zhaomiao

This report summarizes our evaluation of the potential energy-use and GHG-emissions reduction achieved by shifting freight from truck to rail under a most-likely scenario. A sensitivity analysis is also included. The sensitivity analysis shows changes in energy use and GHG emissions when key parameters are varied. The major contribution and distinction from previous studies is that this study considers the rail level of service (LOS) and commodity movements at the origin-destination (O-D) level. In addition, this study considers the fragility and time sensitivity of each commodity type.

Effect of low-speed impact damage on the buckling properties of E-glass/epoxy laminates

NASA Astrophysics Data System (ADS)

Yapici, A.; Metin, M.

2009-11-01

The postimpact buck ling loads of E-glass/epoxy laminates have been measured. Composite samples with the stacking sequence [+45/-45/90/0]2s were subjected to low-speed impact loadings at various energy levels. The tests were conducted on a specially developed vertical drop-weight testing machine. The main impact parameters, such as the peak load, absorbed energy, deflection at the peak load, and damage area, were evaluated and com pared. The damaged specimens were subjected to compressive axial forces, and their buckling loads were determined. The relation between the level of impact energy and buck ling loads is investigated.

Novel solution of power law for γ-bands

NASA Astrophysics Data System (ADS)

Gupta, J. B.

The power law expression E = aIb offers a single-term formula with just two parameters for expressing the level energies in the spectra of even-Z even-N nuclei. Its application to ground band spectra for a wide range of nuclei has been demonstrated in our earlier works. Here, we extend its application to the rotational bands built on an excited state of K = 2 γ-vibration band and Kπ = 0 2+ beta band. A novel assumption of a virtual level with spin zero for γ-bands is made and its validity and use is illustrated. Here, the constancy of the parameters “b” and “a” with spin, offers a more realistic view of the dependence of the nuclear core deformation on spin, in the excited bands. Also, it enables a spinwise view, not available in the other energy fit expressions.

Evolution of two-dimensional plasma parameters in the plane of the wafer during the E- to H- and H- to E-mode transition in an inductively coupled plasma

NASA Astrophysics Data System (ADS)

Park, Il-Seo; Kim, Kyung-Hyun; Kim, Tae-Woo; Kim, Kwan-Youg; Moon, Ho-Jun; Chung, Chin-Wook

2018-05-01

The evolution of plasma parameters during the transition from E- to H- and from H- to E-mode is measured at the wafer level two-dimensionally at low and high pressures. The plasma parameters, such as electron density and electron temperature, are obtained through a floating harmonic sideband method. During the E- to H-mode transition, while the electron kinetics remains in the non-local regime at low pressure, the electron kinetics is changed from the non-local to the local regime at high pressure. The two-dimensional profiles of the electron density at two different pressures have similar convex shape despite different electron kinetics. However, in the case of the electron temperature, at high pressure, the profiles of the electron temperature are changed from flat to convex shape. These results can be understood by the diffusion of the plasma to the wafer-level probe. Moreover, between the transition of E to H and reverse H to E, hysteresis is observed even at the wafer level. The hysteresis is clearly shown at high pressure compared to low pressure. This can be explained by a variation of collisional energy loss including effects of electron energy distribution function (bi-Maxwellian, Maxwellian, Druyvesteyn distribution) on the rate constant and multistep ionization of excited state atoms. During the E- to H-mode transition, Maxwellization is caused by increased electron‑electron collisions, which reduces the collisional energy loss at high pressure (Druyvesteyn distribution) and increases it at low pressure (bi-Maxwellian distribution). Thus, the hysteresis is intensified at high pressure because the reduced collisional energy loss leads to higher ionization efficiency.

The level structure of 124Sb and residual p-n interactions

NASA Astrophysics Data System (ADS)

Alexeev, V. L.; Kondurov, I. A.; Loglnov, Yu. E.; Martynov, V. V.; Sakharov, S. L.; Sushkov, P. A.; Börner, H. G.; Davidson, W. F.; Pinston, J. A.; Schreckenbach, K.

1980-08-01

Gamma and conversion electron spectra following the 123Sb(n, γ) 124Sb reaction in the energy range 35-1030 keV and 16-600 keV, respectively, have been studied with bent crystal and magnetic spectrometers. Gamma-gamma coincidences in the energy range 40-500 keV have been investigated with a Ge(Li)-Ge(Li) arrangement. Gamma-gamma delayed coincidences have been taken with two Ge(Li) detectors in the range 0-10 μs and with a Ge(Li) detector and plastic scintillator in the range 0-300 ns. The 124Sb level scheme involving 40 excited states up to 1060 keV has been constructed. Parity is determined for all the levels. Unique spin values are assigned to 30 levels. The half-lives of the 40.804, 80.764, 125.231 and 248.369 keV levels have been measured to be 3.2 ± 0.3 μs, 4 ± 1 ns, 86 ± 2 ns and 380 ± 70 ps respectively. It is shown that the present level scheme energies differ from those previously found in the 123Sb(d, p) 124Sb reaction by a systematic shift of 40 keV. The (n, γ) levels are found to match up well with those from the (d, p), (n res, γ) and (n, γ primary) reactions. A comparison of the 124Sb level scheme from the (n, γ) reaction with that from the (d, p) reaction and with the 122Sb level scheme enabled the identification of the p g{7}/{2}ns {1}/{2}, p g{7}/{2}n d{3}/{2} π g{7}/{2}ν h{11}/{2}and π d{5}/{2}ν h{11}/{2} two-quasiparticle multiplets. Energy splittings of these p-n configurations by residual interactions taken as a combination of short-range Wigner, singlet and tensor forces have been calculated. It is shown that in order to reproduce experimental branching ratios, configuration mixing should be taken into account, though the amplitudes needed for the admixed configurations are rather small and are, on the average, equal to 0.25. It is also shown that the parameters of residual interactions are about constant in the mass range A = 48 → 210, namely, the parameter of Wigner forces V0 = -32 ± 6 MeV, the singlet force parameter V1 = 14 ± 6 MeV and the range parameter r0 = 1.9 ± 0.3 fm. The occupation numbers of neutrons in the 1 h{11}/{2} subshell in the range A = 110 → 134 and of protons in the 2 d{5}/{2} and 1 g{7}/{2} subshells in the range A = 122 → 142 are determined.

Critical analysis of industrial electron accelerators

NASA Astrophysics Data System (ADS)

Korenev, S.

2004-09-01

The critical analysis of electron linacs for industrial applications (degradation of PTFE, curing of composites, modification of materials, sterlization and others) is considered in this report. Main physical requirements for industrial electron accelerators consist in the variations of beam parameters, such as kinetic energy and beam power. Questions for regulation of these beam parameters are considered. The level of absorbed dose in the irradiated product and throughput determines the main parameters of electron accelerator. The type of ideal electron linac for industrial applications is discussed.

Cost projections for Redox Energy storage systems

NASA Technical Reports Server (NTRS)

Michaels, K.; Hall, G.

1980-01-01

A preliminary design and system cost analysis was performed for the redox energy storage system. A conceptual design and cost estimate was prepared for each of two energy applications: (1) electric utility 100-MWh requirement (10-MW for ten hours) for energy storage for utility load leveling application, and (2) a 500-kWh requirement (10-kW for 50 hours) for use with a variety of residential or commercial applications, including stand alone solar photovoltaic systems. The conceptual designs were based on cell performance levels, system design parameters, and special material costs. These data were combined with estimated thermodynamic and hydraulic analysis to provide preliminary system designs. Results indicate that the redox cell stack to be amenable to mass production techniques with a relatively low material cost.

Quasi-Fermi level splitting and sub-bandgap absorptivity from semiconductor photoluminescence

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

Katahara, John K.; Hillhouse, Hugh W., E-mail: h2@uw.edu

A unified model for the direct gap absorption coefficient (band-edge and sub-bandgap) is developed that encompasses the functional forms of the Urbach, Thomas-Fermi, screened Thomas-Fermi, and Franz-Keldysh models of sub-bandgap absorption as specific cases. We combine this model of absorption with an occupation-corrected non-equilibrium Planck law for the spontaneous emission of photons to yield a model of photoluminescence (PL) with broad applicability to band-band photoluminescence from intrinsic, heavily doped, and strongly compensated semiconductors. The utility of the model is that it is amenable to full-spectrum fitting of absolute intensity PL data and yields: (1) the quasi-Fermi level splitting, (2) themore » local lattice temperature, (3) the direct bandgap, (4) the functional form of the sub-bandgap absorption, and (5) the energy broadening parameter (Urbach energy, magnitude of potential fluctuations, etc.). The accuracy of the model is demonstrated by fitting the room temperature PL spectrum of GaAs. It is then applied to Cu(In,Ga)(S,Se){sub 2} (CIGSSe) and Cu{sub 2}ZnSn(S,Se){sub 4} (CZTSSe) to reveal the nature of their tail states. For GaAs, the model fit is excellent, and fitted parameters match literature values for the bandgap (1.42 eV), functional form of the sub-bandgap states (purely Urbach in nature), and energy broadening parameter (Urbach energy of 9.4 meV). For CIGSSe and CZTSSe, the model fits yield quasi-Fermi leveling splittings that match well with the open circuit voltages measured on devices made from the same materials and bandgaps that match well with those extracted from EQE measurements on the devices. The power of the exponential decay of the absorption coefficient into the bandgap is found to be in the range of 1.2 to 1.6, suggesting that tunneling in the presence of local electrostatic potential fluctuations is a dominant factor contributing to the sub-bandgap absorption by either purely electrostatic (screened Thomas-Fermi) or a photon-assisted tunneling mechanism (Franz-Keldysh). A Gaussian distribution of bandgaps (local E{sub g} fluctuation) is found to be inconsistent with the data. The sub-bandgap absorption of the CZTSSe absorber is found to be larger than that for CIGSSe for materials that yield roughly equivalent photovoltaic devices (8% efficient). Further, it is shown that fitting only portions of the PL spectrum (e.g., low energy for energy broadening parameter and high energy for quasi-Fermi level splitting) may lead to significant errors for materials with substantial sub-bandgap absorption and emission.« less

Exploring energy loss by vector flow mapping in children with ventricular septal defect: Pathophysiologic significance.

PubMed

Honda, Takashi; Itatani, Keiichi; Takanashi, Manabu; Kitagawa, Atsushi; Ando, Hisashi; Kimura, Sumito; Oka, Norihiko; Miyaji, Kagami; Ishii, Masahiro

2017-10-01

Vector flow mapping is a novel echocardiographic flow visualization method, and it has enabled us to quantitatively evaluate the energy loss in the left ventricle (intraventricular energy loss). Although intraventricular energy loss is assumed to be a part of left ventricular workload itself, it is unclear what this parameter actually represents. The aim of the present study was to elucidate the characteristics of intraventricular energy loss. We enrolled 26 consecutive children with ventricular septal defect (VSD). On echocardiography vector flow mapping, intraventricular energy loss was measured in the apical 3-chamber view. We measured peak energy loss and averaged energy loss in the diastolic and systolic phases, and subsequently compared these parameters with catheterization parameters and serum brain natrium peptide (BNP) level. Diastolic, peak, and systolic energy loss were strongly and positively correlated with right ventricular systolic pressure (r=0.76, 0.68, and 0.56, p<0.0001, = 0.0001, and 0.0029, respectively) and right ventricular end diastolic pressure (r=0.55, 0.49, and 0.49, p=0.0038, 0.0120, and 0.0111, respectively). In addition, diastolic, peak, and systolic energy loss were significantly correlated with BNP (r=0.75, 0.69 and 0.49, p<0.0001, < 0.0001, and=0.0116, respectively). In children with VSD, elevated right ventricular pressure is one of the factors that increase energy loss in the left ventricle. The results of the present study encourage further studies in other study populations to elucidate the characteristics of intraventricular energy loss for its possible clinical application. Copyright © 2017 Elsevier B.V. All rights reserved.

Effect of doping on electronic properties of HgSe

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

Nag, Abhinav, E-mail: abhinavn76@gmail.com; Sastri, O. S. K. S., E-mail: sastri.osks@gmail.com; Kumar, Jagdish, E-mail: jagdishphysicist@gmail.com

2016-05-23

First principle study of electronic properties of pure and doped HgSe have been performed using all electron Full Potential Linearized Augmented Plane Wave (FP-LAPW) method using ELK code. The electronic exchange and co-relations are considered using Generalized Gradient Approach (GGA). Lattice parameter, Density of States (DOS) and Band structure calculations have been performed. The total energy curve (Energy vs Lattice parameter), DOS and band structure calculations are in good agreement with the experimental values and those obtained using other DFT codes. The doped material is studied within the Virtual Crystal Approximation (VCA) with doping levels of 10% to 25% ofmore » electrons (hole) per unit cell. Results predict zero band gap in undopedHgSe and bands meet at Fermi level near the symmetry point Γ. For doped HgSe, we found that by electron (hole) doping, the point where conduction and valence bands meet can be shifted below (above) the fermi level.« less

On the Interpretation of the level structure of the Ground 3d5 Manifold of Mn III, Fe IV, Co V and Ni VI

NASA Astrophysics Data System (ADS)

Leushin, A. M.

2011-10-01

The level structure of the ground 3d5 configuration of Mn2+, Fe3+, Co4+ and Ni5+ ions was theoretically interpreted by means of a least-squares fit of the energy parameters to the observed values within the framework of the single-configuration approximation. In the Hamiltonian in addition to real electrostatic, spin-orbit, and spin-spin interactions, electrostatic and spin-orbit interactions correlated by configuration mixing were included. It was shown that the correct positions of almost all the energy levels are determined when the Hamiltonian includes the terms of the lineal (two-body operators) and nonlinear (three-body operators) theory of the configuration interaction. The most correct theoretical description of the experimental spectra was obtained by taking into account relativistic interactions and correlation effects of spin-orbit interactions. Adjustable parameters of the interactions included into the Hamiltonian were found.

EFFECT OF DIETARY PROTEIN AND CARBOHYDRATE LEVELS ON WEIGHT GAIN AND GONAD PRODUCTION IN THE SEA URCHIN LYTECHINUS VARIEGATUS

PubMed Central

Heflin, Laura E.; Gibbs, Victoria K.; Powell, Mickie L; Makowsky, Robert; Lawrence, John M.; Lawrence, Addison L.; Watts, Stephen A.

2014-01-01

Adult Lytechinus variegatus were fed eight formulated diets with different protein (ranging from 12 to 36%) and carbohydrate (ranging from 21 to 39 %) levels. Each sea urchin (n = 8 per treatment) was fed a daily sub-satiation ration of 1.5% of average body weight for 9 weeks. Akaike information criterion analysis was used to compare six different hypothesized dietary composition models across eight growth measurements. Dietary protein level and protein: energy ratio were the best models for prediction of total weight gain. Diets with the highest (> 68.6 mg P kcal−-1) protein: energy ratios produced the most wet weight gain after 9 weeks. Dietary carbohydrate level was a poor predictor for most growth parameters examined in this study. However, the model containing a protein × carbohydrate interaction effect was the best model for protein efficiency ratio (PER). PER decreased with increasing dietary protein level, more so at higher carbohydrate levels. Food conversion ratio (FCR) was best modeled by total dietary energy levels: Higher energy diets produced lower FCRs. Dietary protein level was the best model of gonad wet weight gain. These data suggest that variations in dietary nutrients and energy differentially affect organismal growth and growth of body components. PMID:24994942

Assessing Nutritional Parameters of Brown Bear Diets among Ecosystems Gives Insight into Differences among Populations.

PubMed

López-Alfaro, Claudia; Coogan, Sean C P; Robbins, Charles T; Fortin, Jennifer K; Nielsen, Scott E

2015-01-01

Food habit studies are among the first steps used to understand wildlife-habitat relationships. However, these studies are in themselves insufficient to understand differences in population productivity and life histories, because they do not provide a direct measure of the energetic value or nutritional composition of the complete diet. Here, we developed a dynamic model integrating food habits and nutritional information to assess nutritional parameters of brown bear (Ursus arctos) diets among three interior ecosystems of North America. Specifically, we estimate the average amount of digestible energy and protein (per kilogram fresh diet) content in the diet and across the active season by bears living in western Alberta, the Flathead River (FR) drainage of southeast British Columbia, and the Greater Yellowstone Ecosystem (GYE). As well, we estimate the proportion of energy and protein in the diet contributed by different food items, thereby highlighting important food resources in each ecosystem. Bear diets in Alberta had the lowest levels of digestible protein and energy through all seasons, which might help explain the low reproductive rates of this population. The FR diet had protein levels similar to the recent male diet in the GYE during spring, but energy levels were lower during late summer and fall. Historic and recent diets in GYE had the most energy and protein, which is consistent with their larger body sizes and higher population productivity. However, a recent decrease in consumption of trout (Oncorhynchus clarki), whitebark pine nuts (Pinus albicaulis), and ungulates, particularly elk (Cervus elaphus), in GYE bears has decreased the energy and protein content of their diet. The patterns observed suggest that bear body size and population densities are influenced by seasonal availability of protein an energy, likely due in part to nutritional influences on mass gain and reproductive success.

Assessing Nutritional Parameters of Brown Bear Diets among Ecosystems Gives Insight into Differences among Populations

PubMed Central

López-Alfaro, Claudia; Coogan, Sean C. P.; Robbins, Charles T.; Fortin, Jennifer K.; Nielsen, Scott E.

2015-01-01

Food habit studies are among the first steps used to understand wildlife-habitat relationships. However, these studies are in themselves insufficient to understand differences in population productivity and life histories, because they do not provide a direct measure of the energetic value or nutritional composition of the complete diet. Here, we developed a dynamic model integrating food habits and nutritional information to assess nutritional parameters of brown bear (Ursus arctos) diets among three interior ecosystems of North America. Specifically, we estimate the average amount of digestible energy and protein (per kilogram fresh diet) content in the diet and across the active season by bears living in western Alberta, the Flathead River (FR) drainage of southeast British Columbia, and the Greater Yellowstone Ecosystem (GYE). As well, we estimate the proportion of energy and protein in the diet contributed by different food items, thereby highlighting important food resources in each ecosystem. Bear diets in Alberta had the lowest levels of digestible protein and energy through all seasons, which might help explain the low reproductive rates of this population. The FR diet had protein levels similar to the recent male diet in the GYE during spring, but energy levels were lower during late summer and fall. Historic and recent diets in GYE had the most energy and protein, which is consistent with their larger body sizes and higher population productivity. However, a recent decrease in consumption of trout (Oncorhynchus clarki), whitebark pine nuts (Pinus albicaulis), and ungulates, particularly elk (Cervus elaphus), in GYE bears has decreased the energy and protein content of their diet. The patterns observed suggest that bear body size and population densities are influenced by seasonal availability of protein an energy, likely due in part to nutritional influences on mass gain and reproductive success. PMID:26083536

The third spectrum of rhenium (Re III): Analysis of the (5d5 + 5d46s)-(5d46p + 5d36s6p) transition array

NASA Astrophysics Data System (ADS)

Azarov, Vladimir I.; Gayasov, Robert R.

2018-05-01

The spectrum of rhenium was observed in the (1017-2074) Å wavelength region. The (5d5 + 5d46s)-(5d46p + 5d36s6p) transition array of two times ionized rhenium, Re III, has been investigated and 1305 spectral lines have been classified in the region. The analysis has led to the determination of the 5d5, 5d46s, 5d46p and 5d36s6p configurations. Seventy levels of the 5d5 and 5d46s configurations in the even system and 161 levels of the 5d46p and 5d36s6p configurations in the odd system have been established. The orthogonal operators technique was used to calculate the level structure and transition probabilities. The energy parameters have been determined by the least squares fit to the observed levels. Calculated transition probability and energy values, as well as LS-compositions obtained from the fitted parameters are presented.

Water bicarbonate modulates the response of the shore crab Carcinus maenas to ocean acidification.

PubMed

Maus, Bastian; Bock, Christian; Pörtner, Hans-O

2018-05-23

Ocean acidification causes an accumulation of CO 2 in marine organisms and leads to shifts in acid-base parameters. Acid-base regulation in gill breathers involves a net increase of internal bicarbonate levels through transmembrane ion exchange with the surrounding water. Successful maintenance of body fluid pH depends on the functional capacity of ion-exchange mechanisms and associated energy budget. For a detailed understanding of the dependence of acid-base regulation on water parameters, we investigated the physiological responses of the shore crab Carcinus maenas to 4 weeks of ocean acidification [OA, P(CO 2 ) w  = 1800 µatm], at variable water bicarbonate levels, paralleled by changes in water pH. Cardiovascular performance was determined together with extra-(pH e ) and intracellular pH (pH i ), oxygen consumption, haemolymph CO 2 parameters, and ion composition. High water P(CO 2 ) caused haemolymph P(CO 2 ) to rise, but pH e and pH i remained constant due to increased haemolymph and cellular [HCO 3 - ]. This process was effective even under reduced seawater pH and bicarbonate concentrations. While extracellular cation concentrations increased throughout, anion levels remained constant or decreased. Despite similar levels of haemolymph pH and ion concentrations under OA, metabolic rates, and haemolymph flow were significantly depressed by 40 and 30%, respectively, when OA was combined with reduced seawater [HCO 3 - ] and pH. Our findings suggest an influence of water bicarbonate levels on metabolic rates as well as on correlations between blood flow and pH e . This previously unknown phenomenon should direct attention to pathways of acid-base regulation and their potential feedback on whole-animal energy demand, in relation with changing seawater carbonate parameters.

In vitro acute exposure to DEHP affects oocyte meiotic maturation, energy and oxidative stress parameters in a large animal model.

PubMed

Ambruosi, Barbara; Uranio, Manuel Filioli; Sardanelli, Anna Maria; Pocar, Paola; Martino, Nicola Antonio; Paternoster, Maria Stefania; Amati, Francesca; Dell'Aquila, Maria Elena

2011-01-01

Phthalates are ubiquitous environmental contaminants because of their use in plastics and other common consumer products. Di-(2-ethylhexyl) phthalate (DEHP) is the most abundant phthalate and it impairs fertility by acting as an endocrine disruptor. The aim of the present study was to analyze the effects of in vitro acute exposure to DEHP on oocyte maturation, energy and oxidative status in the horse, a large animal model. Cumulus cell (CC) apoptosis and oxidative status were also investigated. Cumulus-oocyte complexes from the ovaries of slaughtered mares were cultured in vitro in presence of 0.12, 12 and 1200 µM DEHP. After in vitro maturation (IVM), CCs were removed and evaluated for apoptosis (cytological assessment and TUNEL) and intracellular reactive oxygen species (ROS) levels. Oocytes were evaluated for nuclear chromatin configuration. Matured (Metaphase II stage; MII) oocytes were further evaluated for cytoplasmic energy and oxidative parameters. DEHP significantly inhibited oocyte maturation when added at low doses (0.12 µM; P<0.05). This effect was related to increased CC apoptosis (P<0.001) and reduced ROS levels (P<0.0001). At higher doses (12 and 1200 µM), DEHP induced apoptosis (P<0.0001) and ROS increase (P<0.0001) in CCs without affecting oocyte maturation. In DEHP-exposed MII oocytes, mitochondrial distribution patterns, apparent energy status (MitoTracker fluorescence intensity), intracellular ROS localization and levels, mt/ROS colocalization and total SOD activity did not vary, whereas increased ATP content (P<0.05), possibly of glycolytic origin, was found. Co-treatment with N-Acetyl-Cysteine reversed apoptosis and efficiently scavenged excessive ROS in DEHP-treated CCs without enhancing oocyte maturation. In conclusion, acute in vitro exposure to DEHP inhibits equine oocyte maturation without altering ooplasmic energy and oxidative stress parameters in matured oocytes which retain the potential to be fertilized and develop into embryos even though further studies are necessary to confirm this possibility.

In Vitro Acute Exposure to DEHP Affects Oocyte Meiotic Maturation, Energy and Oxidative Stress Parameters in a Large Animal Model

PubMed Central

Sardanelli, Anna Maria; Pocar, Paola; Martino, Nicola Antonio; Paternoster, Maria Stefania; Amati, Francesca; Dell'Aquila, Maria Elena

2011-01-01

Phthalates are ubiquitous environmental contaminants because of their use in plastics and other common consumer products. Di-(2-ethylhexyl) phthalate (DEHP) is the most abundant phthalate and it impairs fertility by acting as an endocrine disruptor. The aim of the present study was to analyze the effects of in vitro acute exposure to DEHP on oocyte maturation, energy and oxidative status in the horse, a large animal model. Cumulus cell (CC) apoptosis and oxidative status were also investigated. Cumulus-oocyte complexes from the ovaries of slaughtered mares were cultured in vitro in presence of 0.12, 12 and 1200 µM DEHP. After in vitro maturation (IVM), CCs were removed and evaluated for apoptosis (cytological assessment and TUNEL) and intracellular reactive oxygen species (ROS) levels. Oocytes were evaluated for nuclear chromatin configuration. Matured (Metaphase II stage; MII) oocytes were further evaluated for cytoplasmic energy and oxidative parameters. DEHP significantly inhibited oocyte maturation when added at low doses (0.12 µM; P<0.05). This effect was related to increased CC apoptosis (P<0.001) and reduced ROS levels (P<0.0001). At higher doses (12 and 1200 µM), DEHP induced apoptosis (P<0.0001) and ROS increase (P<0.0001) in CCs without affecting oocyte maturation. In DEHP-exposed MII oocytes, mitochondrial distribution patterns, apparent energy status (MitoTracker fluorescence intensity), intracellular ROS localization and levels, mt/ROS colocalization and total SOD activity did not vary, whereas increased ATP content (P<0.05), possibly of glycolytic origin, was found. Co-treatment with N-Acetyl-Cysteine reversed apoptosis and efficiently scavenged excessive ROS in DEHP-treated CCs without enhancing oocyte maturation. In conclusion, acute in vitro exposure to DEHP inhibits equine oocyte maturation without altering ooplasmic energy and oxidative stress parameters in matured oocytes which retain the potential to be fertilized and develop into embryos even though further studies are necessary to confirm this possibility. PMID:22076161

Convergence of Ground and Excited State Properties of Divacancy Defects in 4H-SiC with Computational Cell Size

DTIC Science & Technology

2018-03-01

computational parameters needs to be established. We used density functional theory to compute defect formation energies of the neutral and charged hh... energies for the 3A to 3E transition (absorption, zero phonon lines, and emission), which is essential for optical initialization and read-out. We...PBE, defect formation energy , charge transition levels, absorption, zero phonon lines, emission 16. SECURITY CLASSIFICATION OF: 17. LIMITATION

Electron Transport and Nonlinear Optical Properties of Substituted Aryldimesityl Boranes: A DFT Study

PubMed Central

Pandith, Altaf Hussain; Islam, Nasarul

2014-01-01

A comprehensive theoretical study was carried out on a series of aryldimesityl borane (DMB) derivatives using Density Functional theory. Optimized geometries and electronic parameters like electron affinity, reorganization energy, frontiers molecular contours, polarizability and hyperpolarizability have been calculated by employing B3PW91/6-311++G (d, p) level of theory. Our results show that the Hammett function and geometrical parameters correlates well with the reorganization energies and hyperpolarizability for the series of DMB derivatives studied in this work. The orbital energy study reveals that the electron releasing substituents increase the LUMO energies and electron withdrawing substituents decrease the LUMO energies, reflecting the electron transport character of aryldimesityl borane derivatives. From frontier molecular orbitals diagram it is evident that mesityl rings act as the donor, while the phenylene and Boron atom appear as acceptors in these systems. The calculated hyperpolarizability of secondary amine derivative of DMB is 40 times higher than DMB (1). The electronic excitation contributions to the hyperpolarizability studied by using TDDFT calculation shows that hyperpolarizability correlates well with dipole moment in ground and excited state and excitation energy in terms of the two-level model. Thus the results of these calculations can be helpful in designing the DMB derivatives for efficient electron transport and nonlinear optical material by appropriate substitution with electron releasing or withdrawing substituents on phenyl ring of DMB system. PMID:25479382

Characterization of pi-Conjugated Polymers for Transistor and Photovoltaic Applications

NASA Astrophysics Data System (ADS)

Paulsen, Bryan D.

pi-Conjugated polymers represent a unique class of optoelectronic materials. Being polymers, they are solution processable and inherently "soft" materials. This makes them attractive candidates for the production of roll-to-roll printed electronic devices on flexible substrates. The optical and electronic properties of pi-conjugated polymers are synthetically tunable allowing material sets to be tailored to specific applications. Two of the most heavily researched applications are the thin film transistor, the building block of electronic circuits, and the bulk heterojunction solar cell, which holds great potential as a renewable energy source. Key to developing commercially feasible pi-conjugated polymer devices is a thorough understanding of the electronic structure and charge transport behavior of these materials in relationship with polymer structure. Here this structure property relationship has been investigated through electrical and electrochemical means in concert with a variety of other characterization techniques and device test beds. The tunability of polymer optical band gap and frontier molecular orbital energy level was investigated in systems of vinyl incorporating statistical copolymers. Energy levels and band gaps are crucial parameters in developing efficient photovoltaic devices, with control of these parameters being highly desirable. Additionally, charge transport and density of electronic states were investigated in pi-conjugated polymers at extremely high electrochemically induced charge density. Finally, the effects of molecular weight on pi-conjugated polymer optical properties, energy levels, charge transport, morphology, and photovoltaic device performance was examined.

Nuclear power propulsion system for spacecraft

NASA Astrophysics Data System (ADS)

Koroteev, A. S.; Oshev, Yu. A.; Popov, S. A.; Karevsky, A. V.; Solodukhin, A. Ye.; Zakharenkov, L. E.; Semenkin, A. V.

2015-12-01

The proposed designs of high-power space tugs that utilize solar or nuclear energy to power an electric jet engine are reviewed. The conceptual design of a nuclear power propulsion system (NPPS) is described; its structural diagram, gas circuit, and electric diagram are discussed. The NPPS incorporates a nuclear reactor, a thermal-to-electric energy conversion system, a system for the conversion and distribution of electric energy, and an electric propulsion system. Two criterion parameters were chosen in the considered NPPS design: the temperature of gaseous working medium at the nuclear reactor outlet and the rotor speed of turboalternators. The maintenance of these parameters at a given level guarantees that the needed electric voltage is generated and allows for power mode control. The processes of startup/shutdown and increasing/reducing the power, the principles of distribution of electric energy over loads, and the probable emergencies for the proposed NPPS design are discussed.

A power-law coupled three-form dark energy model

NASA Astrophysics Data System (ADS)

Yao, Yan-Hong; Yan, Yang-Jie; Meng, Xin-He

2018-02-01

We consider a field theory model of coupled dark energy which treats dark energy as a three-form field and dark matter as a spinor field. By assuming the effective mass of dark matter as a power-law function of the three-form field and neglecting the potential term of dark energy, we obtain three solutions of the autonomous system of evolution equations, including a de Sitter attractor, a tracking solution and an approximate solution. To understand the strength of the coupling, we confront the model with the latest Type Ia Supernova, Baryon Acoustic Oscillations and Cosmic Microwave Background radiation observations, with the conclusion that the combination of these three databases marginalized over the present dark matter density parameter Ω _{m0} and the present three-form field κ X0 gives stringent constraints on the coupling constant, - 0.017< λ <0.047 (2σ confidence level), by which we present the model's applicable parameter range.

Critical system issues and modeling requirements: The problem of beam energy sweep in an electron linear induction accelerator

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

Turner, W.C.; Barrett, D.M.; Sampayan, S.E.

1990-08-06

In this paper we discuss system issues and modeling requirements within the context of energy sweep in an electron linear induction accelerator. When needed, particular parameter values are taken from the ETA-II linear induction accelerator at Lawrence Livermore National Laboratory. For this paper, the most important parameter is energy sweep during a pulse. It is important to have low energy sweep to satisfy the FEL resonance condition and to limit the beam corkscrew motion. It is desired to achieve {Delta}E/E = {plus minus}1% for a 50-ns flattop whereas the present level of performance is {Delta}E/E = {plus minus}1% in 10more » ns. To improve this situation we will identify a number of areas in which modeling could help increase understanding and improve our ability to design linear induction accelerators.« less

Developing conjugated polymers with high electron affinity by replacing a C-C unit with a B←N unit.

PubMed

Dou, Chuandong; Ding, Zicheng; Zhang, Zijian; Xie, Zhiyuan; Liu, Jun; Wang, Lixiang

2015-03-16

The key parameters of conjugated polymers are lowest unoccupied molecular orbital (LUMO) and highest occupied molecular orbital (HOMO) energy levels. Few approaches can simultaneously lower LUMO and HOMO energy levels of conjugated polymers to a large extent (>0.5 eV). Disclosed herein is a novel strategy to decrease both LUMO and HOMO energy levels of conjugated polymers by about 0.6 eV through replacement of a C-C unit by a B←N unit. The replacement makes the resulting polymer transform from an electron donor into an electron acceptor, and is proven by fluorescence quenching experiments and the photovoltaic response. This work not only provides an effective approach to tune the LUMO/HOMO energy levels of conjugated polymers, but also uses organic boron chemistry as a new toolbox to develop conjugated polymers with high electron affinity for polymer optoelectronic devices. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Safety and performance enhancement circuit for primary explosive detonators

DOEpatents

Davis, Ronald W [Tracy, CA

2006-04-04

A safety and performance enhancement arrangement for primary explosive detonators. This arrangement involves a circuit containing an energy storage capacitor and preset self-trigger to protect the primary explosive detonator from electrostatic discharge (ESD). The circuit does not discharge into the detonator until a sufficient level of charge is acquired on the capacitor. The circuit parameters are designed so that normal ESD environments cannot charge the protection circuit to a level to achieve discharge. When functioned, the performance of the detonator is also improved because of the close coupling of the stored energy.

Load leveling on industrial refrigeration systems

NASA Astrophysics Data System (ADS)

Bierenbaum, H. S.; Kraus, A. D.

1982-01-01

A computer model was constructed of a brewery with a 2000 horsepower compressor/refrigeration system. The various conservation and load management options were simulated using the validated model. The savings available for implementing the most promising options were verified by trials in the brewery. Result show that an optimized methodology for implementing load leveling and energy conservation consisted of: (1) adjusting (or tuning) refrigeration systems controller variables to minimize unnecessary compressor starts, (2) The primary refrigeration system operating parameters, compressor suction pressure, and discharge pressure are carefully controlled (modulated) to satisfy product quality constraints (as well as in-process material cooling rates and temperature levels) and energy evaluating the energy cost savings associated with reject heat recovery, and (4) a decision is made to implement the reject heat recovery system based on a cost/benefits analysis.

Energy levels distribution in supersaturated silicon with titanium for photovoltaic applications

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

Pérez, E., E-mail: eduper@ele.uva.es; Castán, H.; García, H.

2015-01-12

In the attempt to form an intermediate band in the bandgap of silicon substrates to give it the capability to absorb infrared radiation, we studied the deep levels in supersaturated silicon with titanium. The technique used to characterize the energy levels was the thermal admittance spectroscopy. Our experimental results showed that in samples with titanium concentration just under Mott limit there was a relationship among the activation energy value and the capture cross section value. This relationship obeys to the well known Meyer-Neldel rule, which typically appears in processes involving multiple excitations, like carrier capture/emission in deep levels, and itmore » is generally observed in disordered systems. The obtained characteristic Meyer-Neldel parameters were Tmn = 176 K and kTmn = 15 meV. The energy value could be associated to the typical energy of the phonons in the substrate. The almost perfect adjust of all experimental data to the same straight line provides further evidence of the validity of the Meyer Neldel rule, and may contribute to obtain a deeper insight on the ultimate meaning of this phenomenon.« less

Calculation of SF6-/SF6 and Cl-/CFCl3 electron attachment cross sections in the energy range 0-100 meV

NASA Technical Reports Server (NTRS)

Chutjian, A.

1982-01-01

Electron attachment cross sections for the processes SF6-/SF6 and Cl-/CFCl3 are calculated in a local theory using a model in which diatomic-like potential energy curves for the normal modes are constructed from available spectroscopic data. Thermally populated vibrational and rotational levels are included. Good agreement is found with experimental cross sections in the energy range 5-100 meV for a particular choice of potential energy curve parameters.

Effects crude protein levels on female Nile tilapia (Oreochromis niloticus) reproductive performance parameters.

PubMed

de Oliveira, Marinez Moraes; Ribeiro, Tainá; Orlando, Tamira Maria; de Oliveira, Dênio Garcia Silva; Drumond, Mariana Martins; de Freitas, Rilke Tadeu Fonseca; Rosa, Priscila Vieira

2014-11-10

The goal of the present work was to study the reproductive performance of Nile Tilapia (Oreochromis niloticus) female broodstock fed diets containing different levels of crude protein (CP). Two hundred and forty Nile tilapia (O. niloticus) were used at an average age of 30 months, with 180 females and 60 males. The broodstock were lodged separately in masonry tanks with continuous water flow. The females were stocked in thirty tanks with dimensions of 8 m(3) in a completely randomized design consisting of five treatments and six replications. The treatments consisted of five diets with different levels of CP (32, 34, 36, 38 and 40%) and with digestible energy per gram of protein of 9.5 kg of feed. The crude protein (CP) levels positively influenced (p<0.05) reproductive parameters (female relative and absolute fecundity, egg diameter, fasting larvae survival capacity), the somatic indexes (gonadosomatic (GSI), hepatosomatic (HIS), viscerosomatic (VSI)), total plasma protein, albumin and triglycerides. There were no significant differences (p>0.05) observed with regard to spawning weight and female weight. The reproductive parameters studied in the present research indicate that diets formulated with 38% CP with digestible energy per gram of CP of 9.5 were the best diets for tilapia females during the reproductive period. Copyright © 2014 Elsevier B.V. All rights reserved.

Energy usage while maintaining thermal comfort: A case study of a UNT dormitory

NASA Astrophysics Data System (ADS)

Gambrell, Dusten

Campus dormitories for the University of North Texas house over 5500 students per year; each one of them requires certain comfortable living conditions while they live there. There is an inherit amount of money required in order to achieve minimal comfort levels; the cost is mostly natural gas for water and room heating and electricity for cooling, lighting and peripherals. The US Department of Energy has developed several programs to aid in performing energy simulations to help those interested design more cost effective building designs. Energy-10 is such a program that allows users to conduct whole house evaluations by reviewing and altering a few parameters such as building materials, solar heating, energy efficient windows etc. The idea of this project was to recreate a campus dormitory and try to emulate existent energy consumption then try to find ways of lowering that usage while maintaining a high level of personal comfort.

Determination of crystal-field energy levels and temperature dependence of magnetic susceptibility for Dy3+ in [Dy2Pd] heterometallic complex.

PubMed

Karbowiak, Mirosław; Rudowicz, Czesław; Ishida, Takayuki

2013-11-18

This study is the first in a series of experimental and theoretical investigations of the crystal-field (CF) energy levels obtained from optical electronic spectra for selected heterometallic 4f-3d compounds intensively studied for the development of novel single-molecule magnets (SMMs). An intriguing question is why the [{Dy(III)(hfac)3}2Cu(II)(dpk)2] (abbreviated as [Dy2Cu]; Hhfac = 1,1,1,5,5,5-hexafluoropentane-2,4-dione, Hdpk = di-2-pyridyl ketoxime) has antiferromagnetic coupling, whereas [Gd2Cu] and heavy [Ln2Cu] systems usually show ferromagnetic coupling. As the first step to explain this peculiarity, the recently synthesized complex, [Dy2Pd], is investigated. This complex is isostructural with [Dy2Cu] yet contains the diamagnetic Pd ion instead of the magnetic Cu(II) ion. Experimental energy levels of Dy(3+) ions in the powder [Dy2Pd] sample were determined from the 4.2 K absorption spectra. CF analysis was performed yielding the fitted free ion and CF parameters. The number of freely varied parameters was restricted using the superposition model. The fittings yield very satisfactory agreement between the experimental and the calculated energy levels (rms = 12.0 cm(-1)). The energies and exact composition of the state vector for the ground multiplet (6)H(15/2) of Dy(3+) are determined. These results are used for the simulation of the temperature dependence of the magnetic susceptibility, which enables the theoretical interpretation of the experimentally measured magnetic susceptibility in the range 1.8-300 K for the [Dy2Pd] complex. This study provides background for the subsequent investigation of the magnetic exchange interactions in the pertinent heterometallic complexes.

New test of the equivalence principle from lunar laser ranging

NASA Technical Reports Server (NTRS)

Williams, J. G.; Dicke, R. H.; Bender, P. L.; Alley, C. O.; Currie, D. G.; Carter, W. E.; Eckhardt, D. H.

1976-01-01

An analysis of six years of lunar-laser-ranging data gives a zero amplitude for the Nordtvedt term in the earth-moon distance yielding the Nordtvedt parameter eta = 0.00 plus or minus 0.03. Thus, earth's gravitational self-energy contributes equally, plus or minus 3%, to its inertial mass and passive gravitational mass. At the 70% confidence level this result is only consistent with the Brans-Dicke theory for omega greater than 29. We obtain the absolute value of beta - 1 less than about 0.02 to 0.05 for five-parameter parametrized post-Newtonian theories of gravitation with energy-momentum conservation.

Revised and extended analysis of the eighth spectrum of platinum (Pt VIII)

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

Azarov, Vladimir I., E-mail: vlad_azarov@yahoo.com; Gayasov, Robert R.

2017-05-15

The spectrum of platinum was observed in the 300–2100 Å wavelength region. Grazing and normal incidence VUV spectrographs have been used to record the spectrum. The (5d{sup 3}+5d{sup 2}6s)−5d{sup 2}6p transition array of seven times ionized platinum, Pt VIII, has been investigated. The configurations 5d{sup 3} and 5d{sup 2}6p had been previously studied, and all levels of these configurations (19 and 45 levels, respectively) had been established. The previous analysis was based on 178 classified spectral lines. In the current analysis we have confirmed identification of all previously found levels and all but 10 previously assigned spectral lines, although we havemore » detected a large (up to 35 mÅ) systematic shift in wavelength measurements used in the previous analysis. Based on new wavelength measurements, we have corrected the 5d{sup 3} and 5d{sup 2}6p energy level values (by up to 55 cm{sup −1}) and established for the first time 14 out of 16 theoretically possible 5d{sup 2}6s levels in Pt VIII. The total list of identified lines (including 180 new lines) contains 349 entries. The orthogonal operators technique was used to calculate the level structure and transition probabilities. The energy parameters have been determined by the least squares fit to the observed levels. Calculated transition probability and energy values, as well as LS-compositions obtained from the fitted parameters are presented.« less

Cosmological parameter estimation from CMB and X-ray cluster after Planck

NASA Astrophysics Data System (ADS)

Hu, Jian-Wei; Cai, Rong-Gen; Guo, Zong-Kuan; Hu, Bin

2014-05-01

We investigate constraints on cosmological parameters in three 8-parameter models with the summed neutrino mass as a free parameter, by a joint analysis of CCCP X-ray cluster data, the newly released Planck CMB data as well as some external data sets including baryon acoustic oscillation measurements from the 6dFGS, SDSS DR7 and BOSS DR9 surveys, and Hubble Space Telescope H0 measurement. We find that the combined data strongly favor a non-zero neutrino masses at more than 3σ confidence level in these non-vanilla models. Allowing the CMB lensing amplitude AL to vary, we find AL > 1 at 3σ confidence level. For dark energy with a constant equation of state w, we obtain w < -1 at 3σ confidence level. The estimate of the matter power spectrum amplitude σ8 is discrepant with the Planck value at 2σ confidence level, which reflects some tension between X-ray cluster data and Planck data in these non-vanilla models. The tension can be alleviated by adding a 9% systematic shift in the cluster mass function.

Förster resonance energy transfer, absorption and emission spectra in multichromophoric systems. III. Exact stochastic path integral evaluation.

PubMed

Moix, Jeremy M; Ma, Jian; Cao, Jianshu

2015-03-07

A numerically exact path integral treatment of the absorption and emission spectra of open quantum systems is presented that requires only the straightforward solution of a stochastic differential equation. The approach converges rapidly enabling the calculation of spectra of large excitonic systems across the complete range of system parameters and for arbitrary bath spectral densities. With the numerically exact absorption and emission operators, one can also immediately compute energy transfer rates using the multi-chromophoric Förster resonant energy transfer formalism. Benchmark calculations on the emission spectra of two level systems are presented demonstrating the efficacy of the stochastic approach. This is followed by calculations of the energy transfer rates between two weakly coupled dimer systems as a function of temperature and system-bath coupling strength. It is shown that the recently developed hybrid cumulant expansion (see Paper II) is the only perturbative method capable of generating uniformly reliable energy transfer rates and emission spectra across a broad range of system parameters.

Independent-particle models for light negative atomic ions

NASA Technical Reports Server (NTRS)

Ganas, P. S.; Talman, J. D.; Green, A. E. S.

1980-01-01

For the purposes of astrophysical, aeronomical, and laboratory application, a precise independent-particle model for electrons in negative atomic ions of the second and third period is discussed. The optimum-potential model (OPM) of Talman et al. (1979) is first used to generate numerical potentials for eight of these ions. Results for total energies and electron affinities are found to be very close to Hartree-Fock solutions. However, the OPM and HF electron affinities both depart significantly from experimental affinities. For this reason, two analytic potentials are developed whose inner energy levels are very close to the OPM and HF levels but whose last electron eigenvalues are adjusted precisely with the magnitudes of experimental affinities. These models are: (1) a four-parameter analytic characterization of the OPM potential and (2) a two-parameter potential model of the Green, Sellin, Zachor type. The system O(-) or e-O, which is important in upper atmospheric physics is examined in some detail.

[The 2,3-diphosphoglycerate shunt and stabilization of the ATP level in mammalian erythrocytes].

PubMed

Ataullakhanov, A I; Ataullakhanov, F I; Vitvitskiĭ, V M; Zhabotinskiĭ, A M; Pichugin, A V

1985-06-01

The mechanisms of regulation of energy metabolism in erythrocytes of various mammalian species were investigated. In native erythrocytes of man, sheep, cow, dog and mouse the dependencies of the rates of glucose uptake on ATP concentration (i.e., regulatory parameters of glycolysis) were measured. These parameters plotted in normalized coordinates are not species-specific (invariant). The dependence of the rate of ATP-consuming processes on ATP concentration has been studied for the first time in intact mammalian erythrocytes. This dependence was found to be linear only in the species, in whose erythrocytes the activity of 2,3-diphosphoglycerate shunt is practically zero. In all species under study, the stabilization of ATP level is provided for mainly by the hexokinase-phosphofructokinase system. A comparison of regulatory mechanisms of energy metabolism in mammalian (sheep, cow) erythrocytes, in which the 2,3-diphosphoglycerate shunt is absent, with human and animal erythrocytes, in which this pathway is active, points to the important role of the 2,3-diphosphoglycerate shunt in regulation of energy conversion in erythrocytes. This shunt operates as an additional stabilizer protecting the cell from extremal influences.

Characterization of energy exchange parameters in the Himalayan foothills Pakistan

NASA Astrophysics Data System (ADS)

Khalid, Bushra; Kumar, Mukul; Cholaw, Bueh; Aziz Khan, Junaid; Hayat Khan, Azmat

2017-04-01

The characterization of energy exchange parameters for spring season (April-May) has been done for Margalla hills national park (MHNP) Islamabad, Pakistan. It is important because Islamabad city lies in the foothills of Himalayas and micro meteorological activity makes the climate of surrounding areas. The activity on Himalaya's foothills (i.e., Margalla hills) regulate weather and also provide fresh water to the lakes and ponds by late afternoon thunder showers. This research is also important from the perspective of rain water harvesting in Islamabad, Pakistan. The objective of this study is to characterize the energy exchange parameters in the foothills of great Himalayas particularly on MHNP. Landsat ETM+ imageries have been used for calculating the land surface temperature (LST), normalized difference vegetation index (NDVI), and normalized difference moisture index (NDMI). SPOT 5 image has been used for land use/land cover classification over MHNP. The turbulent fluxes have been calculated by computing the values acquired from the processing of satellite imageries and real time observation data sets. The comparisons have been made between the land and atmospheric temperature and moisture to see the difference and its impacts on weather of twin cities i.e., Islamabad and Rawalpindi. The energy exchange parameters have been characterized by analyzing the impacts of weather parameters and turbulent fluxes on MHNP and surrounding cities. The potential rain water harvesting sites have been marked in the foothills. Weather and surface conditions become more favorable for the growth of vegetation by the end of April as the spring season reaches at its peak. There is the start of growing season in the month of April whereas the vegetation becomes thick over time during the month of May over Margalla hills however, the energy exchange parameters follow the same pattern in May as in April. The relative humidity remains between 18 - 55 % and the atmospheric temperature variations are between 19 to 35 0C during the studied period. As the atmospheric temperature and RH fluctuate, it effects the soil moisture and land surface temperature. Even if the atmospheric temperature rise or fall, the evergreen vegetation is found throughout the year on Margalla hills maintains/regulates the land surface temperature and soil moisture. The latent heat flux cause an increase in the noon temperature and RH levels. It further increases the moisture level in the atmosphere that is greatly supported by sensible heat flux to drive the moisture to the higher vertical levels and cause late afternoon thunder showers on the foothills and surrounding areas. The thundershowers are usually intense that cause light or heavy hail and changes the atmospheric temperature around 20 degrees Celsius in the evening time.

Supplementation with Ca salts of soybean oil interacts with concentrate level in grazing dairy cows: intake, ingestive behavior, and ruminal parameters.

PubMed

Macedo, Fernanda Lopes; Batistel, Fernanda; de Souza, Jonas; Chagas, Lucas Jado; Santos, Flávio Augusto Portela

2016-12-01

In this study, we investigated the associative effects of concentrate levels and Ca salts of soybean oil (CSSO) supplementation on performance and ruminal parameters of mid-lactation dairy cows grazing on tropical pasture. Twenty-four Jersey × Holstein cows were used in a randomized block design and assigned to four treatments arranged in a 2 × 2 factorial design. Factors evaluated were concentrate levels (low, 3 kg/day vs. high, 7 kg/day of concentrate) and CSSO supplementation (without CSSO vs. with 250 g CSSO cow/day). All cows grazed on elephant grass (Pennisetum purpureum cv. Cameroon) and received the supplemental treatments for a 90-day period. The high concentrate level decreased forage intake and grazing time. In addition, the high concentrate level increased rumen propionate concentration and microbial synthesis and tended to decrease ammonia-N compared with low concentrate level. The addition of CSSO tended to decrease valerate, isobutyrate, isovalerate, and microbial synthesis. In conclusion, feeding CSSO for mid lactating cows grazing on tropical pasture had negative effects on rumen function. In contrast, CSSO supplementation tended to interact with concentrate level and increased energy intake when fed at low concentrate level. Feeding the high level of concentrate was an effective strategy to increase energy intake and microbial synthesis and improve N utilization.

Theoretical Study of the Jahn-Teller effect in CH3CN+ (X2E) and CD3CN+ (X2E): multimode spin-vibronic energy level calculations.

PubMed

Zhang, Shiyang; Mo, Yuxiang

2009-10-15

The spin-vibronic energy levels for CH(3)CN(+)(X(2)E) and CD(3)CN(+)(X(2)E) have been calculated using a diabatic model including multimode vibronic couplings and spin-orbit interaction without adjusting any parameter. The diabatic potential energy surfaces are represented by the Taylor expansions including linear, quadratic and bilinear vibronic coupling terms. The normal coordinates used in the Taylor expansion were expressed by the mass-weighted Cartesian coordinates. The adiabatic potential energy surfaces for CH(3)CN(+) and CD(3)CN(+) were calculated at the level of CASPT2/cc-pvtz, and the spin-orbit coupling constant was calculated at the level of MRCI/CAS/cc-pvtz. The spin-orbit energy splittings for the ground vibrational states of CH(3)CN(+)(X(2)E) and CD(3)CN(+)(X(2)E) are 20 and 16 cm(-1), respectively, which are resulted from the quenching of the spin-orbit coupling strength of 51 cm(-1). The calculated spin-vibronic levels are in good agreement with the experimental data. The calculation results show that the Jahn-Teller effects in CH(3)CN(+)(X(2)E) and CD(3)CN(+)(X(2)E) are essential to understand their spin-vibronic energy structure.

Sensitivity of the two-dimensional shearless mixing layer to the initial turbulent kinetic energy and integral length scale

NASA Astrophysics Data System (ADS)

Fathali, M.; Deshiri, M. Khoshnami

2016-04-01

The shearless mixing layer is generated from the interaction of two homogeneous isotropic turbulence (HIT) fields with different integral scales ℓ1 and ℓ2 and different turbulent kinetic energies E1 and E2. In this study, the sensitivity of temporal evolutions of two-dimensional, incompressible shearless mixing layers to the parametric variations of ℓ1/ℓ2 and E1/E2 is investigated. The sensitivity methodology is based on the nonintrusive approach; using direct numerical simulation and generalized polynomial chaos expansion. The analysis is carried out at Reℓ 1=90 for the high-energy HIT region and different integral length scale ratios 1 /4 ≤ℓ1/ℓ2≤4 and turbulent kinetic energy ratios 1 ≤E1/E2≤30 . It is found that the most influential parameter on the variability of the mixing layer evolution is the turbulent kinetic energy while variations of the integral length scale show a negligible influence on the flow field variability. A significant level of anisotropy and intermittency is observed in both large and small scales. In particular, it is found that large scales have higher levels of intermittency and sensitivity to the variations of ℓ1/ℓ2 and E1/E2 compared to the small scales. Reconstructed response surfaces of the flow field intermittency and the turbulent penetration depth show monotonic dependence on ℓ1/ℓ2 and E1/E2 . The mixing layer growth rate and the mixing efficiency both show sensitive dependence on the initial condition parameters. However, the probability density function of these quantities shows relatively small solution variations in response to the variations of the initial condition parameters.

VizieR Online Data Catalog: Vela Junior (RX J0852.0-4622) HESS image (HESS+, 2018)

NASA Astrophysics Data System (ADS)

H. E. S. S. Collaboration; Abdalla, H.; Abramowski, A.; Aharonian, F.; Ait Benkhali, F.; Akhperjanian, A. G.; Andersson, T.; Anguener, E. O.; Arakawa, M.; Arrieta, M.; Aubert, P.; Backes, M.; Balzer, A.; Barnard, M.; Becherini, Y.; Becker Tjus, J.; Berge, D.; Bernhard, S.; Bernloehr, K.; Blackwell, R.; Boettcher, M.; Boisson, C.; Bolmont, J.; Bordas, P.; Bregeon, J.; Brun, F.; Brun, P.; Bryan, M.; Buechele, M.; Bulik, T.; Capasso, M.; Carr, J.; Casanova, S.; Cerruti, M.; Chakraborty, N.; Chalme-Calvet, R.; Chaves, R. C. G.; Chen, A.; Chevalier, J.; Chretien, M.; Coffaro, M.; Colafrancesco, S.; Cologna, G.; Condon, B.; Conrad, J.; Cui, Y.; Davids, I. D.; Decock, J.; Degrange, B.; Deil, C.; Devin, J.; Dewilt, P.; Dirson, L.; Djannati-Atai, A.; Domainko, W.; Donath, A.; Drury, L. O'c.; Dutson, K.; Dyks, J.; Edwards, T.; Egberts, K.; Eger, P.; Ernenwein, J.-P.; Eschbach, S.; Farnier, C.; Fegan, S.; Fernandes, M. V.; Fiasson, A.; Fontaine, G.; Foerster, A.; Funk, S.; Fuessling, M.; Gabici, S.; Gajdus, M.; Gallant, Y. A.; Garrigoux, T.; Giavitto, G.; Giebels, B.; Glicenstein, J. F.; Gottschall, D.; Goyal, A.; Grondin, M.-H.; Hahn, J.; Haupt, M.; Hawkes, J.; Heinzelmann, G.; Henri, G.; Hermann, G.; Hervet, O.; Hinton, J. A.; Hofmann, W.; Hoischen, C.; Holler, M.; Horns, D.; Ivascenko, A.; Iwasaki, H.; Jacholkowska, A.; Jamrozy, M.; Janiak, M.; Jankowsky, D.; Jankowsky, F.; Jingo, M.; Jogler, T.; Jouvin, L.; Jung-Richardt, I.; Kastendieck, M. A.; Katarzynski, K.; Katsuragawa, M.; Katz, U.; Kerszberg, D.; Khangulyan, D.; Khelifi, B.; Kieffer, M.; King, J.; Klepser, S.; Klochkov, D.; Kluzniak, W.; Kolitzus, D.; Komin, Nu.; Kosack, K.; Krakau, S.; Kraus, M.; Krueger, P. P.; Laffon, H.; Lamanna, G.; Lau, J.; Lees, J.-P.; Lefaucheur, J.; Lefranc, V.; Lemiere, A.; Lemoine-Goumard, M.; Lenain, J.-P.; Leser, E.; Lohse, T.; Lorentz, M.; Liu, R.; Lopez-Coto, R.; Lypova, I.; Marandon, V.; Marcowith, A.; Mariaud, C.; Marx, R.; Maurin, G.; Maxted, N.; Mayer, M.; Meintjes, P. J.; Meyer, M.; Mitchell, A. M. W.; Moderski, R.; Mohamed, M.; Mohrmann, L.; Mora, K.; Moulin, E.; Murach, T.; Nakashima, S.; de Naurois, M.; Niederwanger, F.; Niemiec J.; Oakes, L.; O'Brien, P.; Odaka, H.; Oettl, S.; Ohm, S.; Ostrowski, M.; Oya, I.; Padovani, M.; Panter, M.; Parsons, R. D.; Paz Arribas, M.; Pekeur, N. W.; Pelletier, G.; Perennes, C.; Petrucci, P.-O.; Peyaud, B.; Piel, Q.; Pita, S.; Poon, H.; Prokhorov, D.; Prokoph, H.; Puehlhofer, G.; Punch, M.; Quirrenbach, A.; Raab, S.; Reimer, A.; Reimer, O.; Renaud, M.; de Los Reyes, R.; Richter, S.; Rieger, F.; Romoli, C.; Rowell, G.; Rudak, B.; Rulten, C. B.; Sahakian, V.; Saito, S.; Salek, D.; Sanchez, D. A.; Santangelo, A.; Sasaki, M.; Schlickeiser, R.; Schuessler, F.; Schulz, A.; Schwanke, U.; Schwemmer, S.; Seglar-Arroyo, M.; Settimo, M.; Seyffert, A. S.; Shafi, N.; Shilon, I.; Simoni, R.; Sol, H.; Spanier, F.; Spengler, G.; Spies, F.; Stawarz, L.; Steenkamp, R.; Stegmann, C.; Stycz, K.; Sushch, I.; Takahashi, T.; Tavernet, J.-P.; Tavernier, T.; Taylor, A. M.; Terrier, R.; Tibaldo, L.; Tiziani, D.; Tluczykont, M.; Trichard, C.; Tsuji, N.; Tuffs, R.; Uchiyama, Y.; van der, Walt D. J.; van Eldik, C.; van Rensburg, C.; van Soelen, B.; Vasileiadis, G.; Veh, J.; Venter, C.; Viana, A.; Vincent, P.; Vink, J.; Voisin, F.; Voelk, H. J.; Vuillaume, T.; Wadiasingh, Z.; Wagner, S. J.; Wagner, P.; Wagner, R. M.; White, R.; Wierzcholska, A.; Willmann, P.; Woernlein, A.; Wouters, D.; Yang, R.; Zabalza, V.; Zaborov, D.; Zacharias, M.; Zanin, R.; Zdziarski, A. A.; Zech, A.; Zefi, F.; Ziegler, A.; Zywucka, N.

2018-03-01

skymap.fit: H.E.S.S. excess skymap in FITS format of the region comprising Vela Junior and its surroundings. The excess map has been corrected for the gradient of exposure and smoothed with a Gaussian function of width 0.08° to match the analysis point spread function, matching the procedure applied to derive the maps in Fig. 1. sp_stat.txt: H.E.S.S. spectral points and fit parameters for Vela Junior (H.E.S.S. data points in Fig. 3 and Tab. A.2 and H.E.S.S. spectral fit parameters in Tab. 4). The errors in this file represent statistical uncertainties at 1 sigma confidence level. The covariance matrix of the fit is also included in the format: c11 c12 c_13 c21 c22 c_23 c31 c32 c_33 where the subindices represent the following parameters of the power-law with exponential cut-off (ECPL) formula in Tab. 2: 1: flux normalization (Phi0) 2: spectral index (Gamma) 3: inverse of the cutoff energy (lambda=1/Ecut) The units for the covariance matrix are the same as for the fit parameters. Notice that, while the fit parameters section of the file shows E_cut as parameter, the fit was done in lambda=1/Ecut; hence the covariance matrix shows the values for lambda in TeV-1. sp_syst.txt: H.E.S.S. spectral points and fit parameters for Vela Junior (H.E.S.S. data points in Fig. 3 and Tab. A.2 and H.E.S.S. spectral fit parameters in Tab. 4). The errors in this file represent systematic uncertainties at 1 sigma confidence level. The integral fluxes for several energy ranges are also included. (4 data files).

Adapting Human Videofluoroscopic Swallow Study Methods to Detect and Characterize Dysphagia in Murine Disease Models

PubMed Central

Lever, Teresa E.; Braun, Sabrina M.; Brooks, Ryan T.; Harris, Rebecca A.; Littrell, Loren L.; Neff, Ryan M.; Hinkel, Cameron J.; Allen, Mitchell J.; Ulsas, Mollie A.

2015-01-01

This study adapted human videofluoroscopic swallowing study (VFSS) methods for use with murine disease models for the purpose of facilitating translational dysphagia research. Successful outcomes are dependent upon three critical components: test chambers that permit self-feeding while standing unrestrained in a confined space, recipes that mask the aversive taste/odor of commercially-available oral contrast agents, and a step-by-step test protocol that permits quantification of swallow physiology. Elimination of one or more of these components will have a detrimental impact on the study results. Moreover, the energy level capability of the fluoroscopy system will determine which swallow parameters can be investigated. Most research centers have high energy fluoroscopes designed for use with people and larger animals, which results in exceptionally poor image quality when testing mice and other small rodents. Despite this limitation, we have identified seven VFSS parameters that are consistently quantifiable in mice when using a high energy fluoroscope in combination with the new murine VFSS protocol. We recently obtained a low energy fluoroscopy system with exceptionally high imaging resolution and magnification capabilities that was designed for use with mice and other small rodents. Preliminary work using this new system, in combination with the new murine VFSS protocol, has identified 13 swallow parameters that are consistently quantifiable in mice, which is nearly double the number obtained using conventional (i.e., high energy) fluoroscopes. Identification of additional swallow parameters is expected as we optimize the capabilities of this new system. Results thus far demonstrate the utility of using a low energy fluoroscopy system to detect and quantify subtle changes in swallow physiology that may otherwise be overlooked when using high energy fluoroscopes to investigate murine disease models. PMID:25866882

Spectroscopic parameters, vibrational levels, transition dipole moments and transition probabilities of the 9 low-lying states of the NCl+ cation

NASA Astrophysics Data System (ADS)

Yin, Yuan; Shi, Deheng; Sun, Jinfeng; Zhu, Zunlue

2018-03-01

This work calculates the potential energy curves of 9 Λ-S and 28 Ω states of the NCl+ cation. The technique employed is the complete active space self-consistent field method, which is followed by the internally contracted multireference configuration interaction approach with the Davidson correction. The Λ-S states are X2Π, 12Σ+, 14Π, 14Σ+, 14Σ-, 24Π, 14Δ, 16Σ+, and 16Π, which are yielded from the first two dissociation channels of NCl+ cation. The Ω states are generated from these Λ-S states. The 14Π, 14Δ, 16Σ+, and 16Π states are inverted with the spin-orbit coupling effect included. The 14Σ+, 16Σ+, and 16Π states are very weakly bound, whose well depths are only several-hundred cm- 1. One avoided crossing of PECs occurs between the 12Σ+ and 22Σ+ states. To improve the quality of potential energy curves, core-valence correlation and scalar relativistic corrections are included. The potential energies are extrapolated to the complete basis set limit. The spectroscopic parameters and vibrational levels are calculated. The transition dipole moments are computed. The Franck-Condon factors, Einstein coefficients, and radiative lifetimes of many transitions are determined. The spectroscopic approaches are proposed for observing these states according to the transition probabilities. The spin-orbit coupling effect on the spectroscopic and vibrational properties is evaluated. The spectroscopic parameters, vibrational levels, transition dipole moments, as well as transition probabilities reported in this paper could be considered to be very reliable.

Validation of a buffet meal design in an experimental restaurant.

PubMed

Allirot, Xavier; Saulais, Laure; Disse, Emmanuel; Roth, Hubert; Cazal, Camille; Laville, Martine

2012-06-01

We assessed the reproducibility of intakes and meal mechanics parameters (cumulative energy intake (CEI), number of bites, bite rate, mean energy content per bite) during a buffet meal designed in a natural setting, and their sensitivity to food deprivation. Fourteen men were invited to three lunch sessions in an experimental restaurant. Subjects ate their regular breakfast before sessions A and B. They skipped breakfast before session FAST. The same ad libitum buffet was offered each time. Energy intakes and meal mechanics were assessed by foods weighing and video recording. Intrasubject reproducibility was evaluated by determining intraclass correlation coefficients (ICC). Mixed-models were used to assess the effects of the sessions on CEI. We found a good reproducibility between A and B for total energy (ICC=0.82), carbohydrate (ICC=0.83), lipid (ICC=0.81) and protein intake (ICC=0.79) and for meal mechanics parameters. Total energy, lipid and carbohydrate intake were higher in FAST than in A and B. CEI were found sensitive to differences in hunger level while the other meal mechanics parameters were stable between sessions. In conclusion, a buffet meal in a normal eating environment is a valid tool for assessing the effects of interventions on intakes. Copyright © 2012 Elsevier Ltd. All rights reserved.

VTST/MT studies of the catalytic mechanism of C-H activation by transition metal complexes with [Cu2(μ-O2)], [Fe2(μ-O2)] and Fe(IV)-O cores based on DFT potential energy surfaces.

PubMed

Kim, Yongho; Mai, Binh Khanh; Park, Sumin

2017-04-01

High-valent Cu and Fe species, which are generated from dioxygen activation in metalloenzymes, carry out the functionalization of strong C-H bonds. Understanding the atomic details of the catalytic mechanism has long been one of the main objectives of bioinorganic chemistry. Large H/D kinetic isotope effects (KIEs) were observed in the C-H activation by high-valent non-heme Cu or Fe complexes in enzymes and their synthetic models. The H/D KIE depends significantly on the transition state properties, such as structure, energies, frequencies, and shape of the potential energy surface, when the tunneling effect is large. Therefore, theoretical predictions of kinetic parameters such as rate constants and KIEs can provide a reliable link between atomic-level quantum mechanical mechanisms and experiments. The accurate prediction of the tunneling effect is essential to reproduce the kinetic parameters. The rate constants and HD/KIE have been calculated using the variational transition-state theory including multidimensional tunneling based on DFT potential energy surfaces along the reaction coordinate. Excellent agreement was observed between the predicted and experimental results, which assures the validity of the DFT potential energy surfaces and, therefore, the proposed atomic-level mechanisms. The [Cu 2 (μ-O) 2 ], [Fe 2 (μ-O) 2 ], and Fe(IV)-oxo species were employed for C-H activation, and their role as catalysts was discussed at an atomic level.

Influence of insulin on glucose metabolism and energy expenditure in septic patients

PubMed Central

Rusavy, Zdenek; Sramek, Vladimir; Lacigova, Silvie; Novak, Ivan; Tesinsky, Pavel; Macdonald, Ian A

2004-01-01

Introduction It is recognized that administration of insulin with glucose decreases catabolic response in sepsis. The aim of the present study was to compare the effects of two levels of insulinaemia on glucose metabolism and energy expenditure in septic patients and volunteers. Methods Glucose uptake, oxidation and storage, and energy expenditure were measured, using indirect calorimetry, in 20 stable septic patients and 10 volunteers in a two-step hyperinsulinaemic (serum insulin levels 250 and 1250 mIU/l), euglycaemic (blood glucose concentration 5 mmol/l) clamp. Differences between steps of the clamp (from serum insulin 1250 to 250 mIU/l) for all parameters were calculated for each individual, and compared between septic patients and volunteers using the Wilcoxon nonpaired test. Results Differences in glucose uptake and storage were significantly less in septic patients. The differences in glucose oxidation between the groups were not statistically significant. Baseline energy expenditure was significantly higher in septic patients, and there was no significant increase in either step of the clamp in this group; when comparing the two groups, the differences between steps were significantly greater in volunteers. Conclusion A hyperdynamic state of sepsis leads to a decrease in glucose uptake and storage in comparison with healthy volunteers. An increase in insulinaemia leads to an increase in all parameters of glucose metabolism, but the increases in glucose uptake and storage are significantly lower in septic patients. A high level of insulinaemia in sepsis increases glucose uptake and oxidation significantly, but not energy expenditure, in comparison with volunteers. PMID:15312220

Estimation of energy density of Li-S batteries with liquid and solid electrolytes

NASA Astrophysics Data System (ADS)

Li, Chunmei; Zhang, Heng; Otaegui, Laida; Singh, Gurpreet; Armand, Michel; Rodriguez-Martinez, Lide M.

2016-09-01

With the exponential growth of technology in mobile devices and the rapid expansion of electric vehicles into the market, it appears that the energy density of the state-of-the-art Li-ion batteries (LIBs) cannot satisfy the practical requirements. Sulfur has been one of the best cathode material choices due to its high charge storage (1675 mAh g-1), natural abundance and easy accessibility. In this paper, calculations are performed for different cell design parameters such as the active material loading, the amount/thickness of electrolyte, the sulfur utilization, etc. to predict the energy density of Li-S cells based on liquid, polymeric and ceramic electrolytes. It demonstrates that Li-S battery is most likely to be competitive in gravimetric energy density, but not volumetric energy density, with current technology, when comparing with LIBs. Furthermore, the cells with polymer and thin ceramic electrolytes show promising potential in terms of high gravimetric energy density, especially the cells with the polymer electrolyte. This estimation study of Li-S energy density can be used as a good guidance for controlling the key design parameters in order to get desirable energy density at cell-level.

Operation of a wind turbine-flywheel energy storage system under conditions of stochastic change of wind energy.

PubMed

Tomczewski, Andrzej

2014-01-01

The paper presents the issues of a wind turbine-flywheel energy storage system (WT-FESS) operation under real conditions. Stochastic changes of wind energy in time cause significant fluctuations of the system output power and as a result have a negative impact on the quality of the generated electrical energy. In the author's opinion it is possible to reduce the aforementioned effects by using an energy storage of an appropriate type and capacity. It was assumed that based on the technical parameters of a wind turbine-energy storage system and its geographical location one can determine the boundary capacity of the storage, which helps prevent power cuts to the grid at the assumed probability. Flywheel energy storage was selected due to its characteristics and technical parameters. The storage capacity was determined based on an empirical relationship using the results of the proposed statistical and energetic analysis of the measured wind velocity courses. A detailed algorithm of the WT-FESS with the power grid system was developed, eliminating short-term breaks in the turbine operation and periods when the wind turbine power was below the assumed level.

Operation of a Wind Turbine-Flywheel Energy Storage System under Conditions of Stochastic Change of Wind Energy

PubMed Central

2014-01-01

The paper presents the issues of a wind turbine-flywheel energy storage system (WT-FESS) operation under real conditions. Stochastic changes of wind energy in time cause significant fluctuations of the system output power and as a result have a negative impact on the quality of the generated electrical energy. In the author's opinion it is possible to reduce the aforementioned effects by using an energy storage of an appropriate type and capacity. It was assumed that based on the technical parameters of a wind turbine-energy storage system and its geographical location one can determine the boundary capacity of the storage, which helps prevent power cuts to the grid at the assumed probability. Flywheel energy storage was selected due to its characteristics and technical parameters. The storage capacity was determined based on an empirical relationship using the results of the proposed statistical and energetic analysis of the measured wind velocity courses. A detailed algorithm of the WT-FESS with the power grid system was developed, eliminating short-term breaks in the turbine operation and periods when the wind turbine power was below the assumed level. PMID:25215326

Microdosimetry of the full slowing down of protons using Monte Carlo track structure simulations.

PubMed

Liamsuwan, T; Uehara, S; Nikjoo, H

2015-09-01

The article investigates two approaches in microdosimetric calculations based on Monte Carlo track structure (MCTS) simulations of a 160-MeV proton beam. In the first approach, microdosimetric parameters of the proton beam were obtained using the weighted sum of proton energy distributions and microdosimetric parameters of proton track segments (TSMs). In the second approach, phase spaces of energy depositions obtained using MCTS simulations in the full slowing down (FSD) mode were used for the microdosimetric calculations. Targets of interest were water cylinders of 2.3-100 nm in diameters and heights. Frequency-averaged lineal energies ([Formula: see text]) obtained using both approaches agreed within the statistical uncertainties. Discrepancies beyond this level were observed for dose-averaged lineal energies ([Formula: see text]) towards the Bragg peak region due to the small number of proton energies used in the TSM approach and different energy deposition patterns in the TSM and FSD of protons. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Low Velocity Impact Behavior of Basalt Fiber-Reinforced Polymer Composites

NASA Astrophysics Data System (ADS)

Shishevan, Farzin Azimpour; Akbulut, Hamid; Mohtadi-Bonab, M. A.

2017-06-01

In this research, we studied low velocity impact response of homogenous basalt fiber-reinforced polymer (BFRP) composites and then compared the impact key parameters with carbon fiber-reinforced polymer (CFRP) homogenous composites. BFRPs and CFRPs were fabricated by vacuum-assisted resin transfer molding (VARTM) method. Fabricated composites included 60% fiber and 40% epoxy matrix. Basalt and carbon fibers used as reinforcement materials were weaved in 2/2 twill textile tip in the structures of BFRP and CFRP composites. We also utilized the energy profile method to determine penetration and perforation threshold energies. The low velocity impact tests were carried out in 30, 60, 80, 100, 120 and 160 J energy magnitudes, and impact response of BFRPs was investigated by related force-deflection, force-time, deflection-time and absorbed energy-time graphics. The related impact key parameters such as maximum contact force, absorbed energy, deflection and duration time were compared with CFRPs for various impact energy levels. As a result, due to the higher toughness of basalt fibers, a better low velocity impact performance of BFRP than that of CFRP was observed. The effects of fabrication parameters, such as curing process, were studied on the low velocity impact behavior of BFRP. The results of tested new fabricated materials show that the change of fabrication process and curing conditions improves the impact behavior of BFRPs up to 13%.

The shear instability energy: a new parameter for materials design?

NASA Astrophysics Data System (ADS)

Kanani, M.; Hartmaier, A.; Janisch, R.

2017-10-01

Reliable and predictive relationships between fundamental microstructural material properties and observable macroscopic mechanical behaviour are needed for the successful design of new materials. In this study we establish a link between physical properties that are defined on the atomic level and the deformation mechanisms of slip planes and interfaces that govern the mechanical behaviour of a metallic material. To accomplish this, the shear instability energy Γ is introduced, which can be determined via quantum mechanical ab initio calculations or other atomistic methods. The concept is based on a multilayer generalised stacking fault energy calculation and can be applied to distinguish the different shear deformation mechanisms occurring at TiAl interfaces during finite-temperature molecular dynamics simulations. We use the new parameter Γ to construct a deformation mechanism map for different interfaces occurring in this intermetallic. Furthermore, Γ can be used to convert the results of ab initio density functional theory calculations into those obtained with an embedded atom method type potential for TiAl. We propose to include this new physical parameter into material databases to apply it for the design of materials and microstructures, which so far mainly relies on single-crystal values for the unstable and stable stacking fault energy.

Temporal studies of black hole X-ray transients during outburst decay

NASA Astrophysics Data System (ADS)

Kalemci, Emrah

Galactic black holes (GBH) are a class of astrophysical sources with X-ray emission that is powered by accretion from a companion star. An important goal of GBH research is to understand the accretion structure and the nature of the variability of these systems. The GBHs sometimes show significant changes in the X-ray emission properties, and these changes are called state transitions. The transitions are believed to be caused by variation of the mass accretion rate and changes in accretion geometry. Thus, their study provides valuable information on the nature of the accretion structure. In this thesis work, I present results from studying the spectral and temporal evolution of all GBH transients that have been observed with NASA's Rossi X-ray Timing Explorer during outburst decay. I explore the physical conditions before, during and after the state transition, characterize the quasi-periodic oscillations (QPO) and continuum of power spectral density (PSD) in different energy bands, and study the correlations between spectral and temporal fit parameters. I also analyze the evolution of the cross- spectral parameters during and after the transition. I show that the appearance of the broad band variability is coincident with an increase of power-law flux. The evolution of the characteristic frequencies and the spectral parameters after the transition are consistent with retreating of the inner accretion disk. The energy dependent PSD analysis shows that the level of variability increases with energy when there is significant soft flux from the optically thick accretion disk. The variability level also increases with energy if the absorption column density to the source is high. This may be a result of small angle scatterings of lower energy X-ray photons with the ISM dust around these sources. I find global correlations between the spectral index and three temporal fit parameters: the QPO frequency, the overall level of variability and the integrated time lag. The relation between the spectral index and the time lags are interpreted within the context of the average number of Compton scatterings and the temperature of the scattering medium. During the transitions, the average lag is higher and average coherence is lower. I discuss whether a hybrid accretion model, for which the hot electron corona is the base of an optically thin outflow or a jet, can explain the physical properties during the transition.

Influence of granite-grit on nutrient digestibility and haematological parameters of broiler chickens fed rice offal based diets.

PubMed

Idachaba, C U; Abeke, F O; Olugbemi, T S; Ademu, L A

2013-10-01

A total of 270 broiler chickens were used for the study. The birds were fed common diet containing 23% Crude protein and 2864 kcal kg(-1) Metabolizable energy at the starter phase while 20% Crude protein and 2923 kcal kg(-1) Metabolizable energy was fed at the finisher phase. Starter and finisher diets contained 10 and 15% inclusion levels of rice offal respectively. Granite grit was added to the basal diet at 0.0, 2.0, 4.0, 6.0, 8.0 and 10.0 g per bird per month thus making a total of six treatments. Each treatment was replicated three times with 15 birds per replicate in a completely randomized design. Packed cell volume and haemoglobin level were not significantly (p>0.05) affected by dietary grit levels while total protein increased across the graded levels of granite grit. Crude protein, crude fibre and nitrogen free extract significantly (p<0.05) improved with increasing grit levels. These parameters improved up to the highest level of grit addition (10.0 g) granite-grit. It was concluded that 10.0 g granite grit per bird per month is beneficial to broiler chickens as it allows for efficient nutrient utilization. Further study to determine the optimum level of granite grit in broiler diet is encouraged since result obtained showed the optimum level was not attained.

Judd-Ofelt analysis and energy transfer processes of Er3+ and Nd3+ doped fluoroaluminate glasses with low phosphate content

NASA Astrophysics Data System (ADS)

Huang, Feifei; Zhang, Yu; Hu, Lili; Chen, Danping

2014-12-01

Spectroscopic property and energy transfer processes of singly doped and codoped Er3+ and Nd3+ fluoroaluminate glasses with low phosphate content are systematically analyzed. The absorption spectra of these glasses are tested, and the Judd-Ofelt (J-O) and radiative parameters are discussed based on J-O theory and the parameters changes substantially because of the other codoping ions. As for Nd3+: the main emission bands at 0.9 and 1.05 μm decrease in the codoped sample under the excitation of an 800 nm laser diode from the emission spectra because the Er3+: 4I11/2 level reduces the Nd3+: 4F3/2 level effectively through the energy transfer process Nd3+: 4F3/2 → Er3+: 4I11/2. For Er3+, the emission at 1.5 μm is restrained by codoping with Nd3+ ions from the energy transfer process Er3+: 4I13/2 → Nd3+: 4I15/2. The emission at 2.7 μm is enhanced because the Nd3+ ions deplete the lower level and exert a positive effect on the upper laser level. The microparameters of the energy transfer between the Er3+ and Nd3+ ions are calculated and discussed using Forster-Dexter theory. The energy transfer efficiencies of the Nd3+: 4F3/2 to the Er3+: 4I11/2 and the Er3+: 4I13/2 to the Nd3+: 4I15/2 are 28.8% and 74.5%, respectively. These results indicate that Nd3+ can be an efficient sensitizer for Er3+ to obtain Mid-infrared (Mid-IR) emission and the codoped Er3+/Nd3+ fluoroaluminate glass with low phosphate content is suitable to be used as the fiber optical gain media for 2.7 μm laser generation.

A theoretical study of hydrogen complexes of the XH-pi type between propyne and HF, HCL or HCN.

PubMed

Tavares, Alessandra M; da Silva, Washington L V; Lopes, Kelson C; Ventura, Elizete; Araújo, Regiane C M U; do Monte, Silmar A; da Silva, João Bosco P; Ramos, Mozart N

2006-05-15

The present manuscript reports a systematic investigation of the basis set dependence of some properties of hydrogen-bonded (pi type) complexes formed by propyne and a HX molecule, where X=F, Cl and CN. The calculations have been performed at Hartree-Fock, MP2 and B3LYP levels. Geometries, H-bond energies and vibrational have been considered. The more pronounced effects on the structural parameters of the isolated molecules, as a result of complexation, are verified on RCtriple bondC and HX bond lengths. As compared to double-zeta (6-31G**), triple-zeta (6-311G**) basis set leads to an increase of RCtriple bondC bond distance, at all three computational levels. In the case where diffuse functions are added to both hydrogen and 'heavy' atoms, the effect is more pronounced. The propyne-HX structural parameters are quite similar to the corresponding parameters of acetylene-HX complexes, at all levels. The largest difference is obtained for hydrogen bond distance, RH, with a smaller value for propyne-HX complex, indicating a stronger bond. Concerning the electronic properties, the results yield the following ordering for H-bond energies, DeltaE: propynecdots, three dots, centeredHF>propynecdots, three dots, centeredHCl>propynecdots, three dots, centeredHCN. It is also important to point out that the inclusion of BSSE and zero-point energies (ZPE) corrections cause significant changes on DeltaE. The smaller effect of ZPE is obtained for propynecdots, three dots, centeredHCN at HF/6-311++G** level, while the greatest difference is obtained at MP2/6-31G** level for propynecdots, three dots, centeredHF system. Concerning the IR vibrational it was obtained that larger shift can be associated with stronger hydrogen bonds. The more pronounced effect on the normal modes of the isolated molecule after the complexation is obtained for HX stretching frequency, which is shifted downward.

A theoretical study of hydrogen complexes of the X sbnd H-π type between propyne and HF, HCL or HCN

NASA Astrophysics Data System (ADS)

Tavares, Alessandra M.; da Silva, Washington L. V.; Lopes, Kelson C.; Ventura, Elizete; Araújo, Regiane C. M. U.; do Monte, Silmar A.; da Silva, João Bosco P.; Ramos, Mozart N.

2006-05-01

The present manuscript reports a systematic investigation of the basis set dependence of some properties of hydrogen-bonded (π type) complexes formed by propyne and a HX molecule, where X = F, Cl and CN. The calculations have been performed at Hartree-Fock, MP2 and B3LYP levels. Geometries, H-bond energies and vibrational have been considered. The more pronounced effects on the structural parameters of the isolated molecules, as a result of complexation, are verified on RC tbnd C and HX bond lengths. As compared to double-ζ (6-31G **), triple-ζ (6-311G **) basis set leads to an increase of RC tbnd C bond distance, at all three computational levels. In the case where diffuse functions are added to both hydrogen and 'heavy' atoms, the effect is more pronounced. The propyne-HX structural parameters are quite similar to the corresponding parameters of acetylene-HX complexes, at all levels. The largest difference is obtained for hydrogen bond distance, RH, with a smaller value for propyne-HX complex, indicating a stronger bond. Concerning the electronic properties, the results yield the following ordering for H-bond energies, Δ E: propyne⋯HF > propyne⋯HCl > propyne⋯HCN. It is also important to point out that the inclusion of BSSE and zero-point energies (ZPE) corrections cause significant changes on Δ E. The smaller effect of ZPE is obtained for propyne⋯HCN at HF/6-311++G ** level, while the greatest difference is obtained at MP2/6-31G ** level for propyne⋯HF system. Concerning the IR vibrational it was obtained that larger shift can be associated with stronger hydrogen bonds. The more pronounced effect on the normal modes of the isolated molecule after the complexation is obtained for H sbnd X stretching frequency, which is shifted downward.

Metallic artefact reduction with monoenergetic dual-energy CT: systematic ex vivo evaluation of posterior spinal fusion implants from various vendors and different spine levels.

PubMed

Guggenberger, R; Winklhofer, S; Osterhoff, G; Wanner, G A; Fortunati, M; Andreisek, G; Alkadhi, H; Stolzmann, P

2012-11-01

To evaluate optimal monoenergetic dual-energy computed tomography (DECT) settings for artefact reduction of posterior spinal fusion implants of various vendors and spine levels. Posterior spinal fusion implants of five vendors for cervical, thoracic and lumbar spine were examined ex vivo with single-energy (SE) CT (120 kVp) and DECT (140/100 kVp). Extrapolated monoenergetic DECT images at 64, 69, 88, 105 keV and individually adjusted monoenergy for optimised image quality (OPTkeV) were generated. Two independent radiologists assessed quantitative and qualitative image parameters for each device and spine level. Inter-reader agreements of quantitative and qualitative parameters were high (ICC = 0.81-1.00, κ = 0.54-0.77). HU values of spinal fusion implants were significantly different among vendors (P < 0.001), spine levels (P < 0.01) and among SECT, monoenergetic DECT of 64, 69, 88, 105 keV and OPTkeV (P < 0.01). Image quality was significantly (P < 0.001) different between datasets and improved with higher monoenergies of DECT compared with SECT (V = 0.58, P < 0.001). Artefacts decreased significantly (V = 0.51, P < 0.001) at higher monoenergies. OPTkeV values ranged from 123-141 keV. OPTkeV according to vendor and spine level are presented herein. Monoenergetic DECT provides significantly better image quality and less metallic artefacts from implants than SECT. Use of individual keV values for vendor and spine level is recommended. • Artefacts pose problems for CT following posterior spinal fusion implants. • CT images are interpreted better with monoenergetic extrapolation using dual-energy (DE) CT. • DECT extrapolation improves image quality and reduces metallic artefacts over SECT. • There were considerable differences in monoenergy values among vendors and spine levels. • Use of individualised monoenergy values is indicated for different metallic hardware devices.

Spectroscopic study of the radionuclide 21Na for the astrophysical 17F(α ,p )20Ne reaction rate

NASA Astrophysics Data System (ADS)

Cha, S. M.; Chae, K. Y.; Ahn, S.; Bardayan, D. W.; Chipps, K. A.; Cizewski, J. A.; Howard, M. E.; Kozub, R. L.; Kwak, K.; Manning, B.; Matos, M.; O'Malley, P. D.; Pain, S. D.; Peters, W. A.; Pittman, S. T.; Ratkiewicz, A.; Smith, M. S.; Strauss, S.

2017-08-01

The 24Mg(p ,α )21Na reaction was measured at the Holifield Radioactive Ion Beam Facility of the Oak Ridge National Laboratory to study the spectroscopy of the radionuclide 21Na. A 31-MeV proton beam from the 25 MV tandem accelerator bombarded isotopically enriched 24Mg targets. Recoiling 4He particles were identified by an annular silicon strip detector array. Two energy levels at Ex=6.594 and 7.132 MeV were observed for the first time. By comparing the experimentally obtained angular distributions and distorted wave Born approximation calculations, the spins and parities of 21Na energy levels were constrained. The astrophysically-important 17F(α ,p )20Ne reaction rate was also calculated for the first time using resonance parameters for 12 energy levels.

A monostable piezoelectric energy harvester for broadband low-level excitations

NASA Astrophysics Data System (ADS)

Fan, Kangqi; Tan, Qinxue; Zhang, Yiwei; Liu, Shaohua; Cai, Meiling; Zhu, Yingmin

2018-03-01

This letter presents a monostable piezoelectric energy harvester (PEH) for achieving enhanced energy extraction from low-level excitations. The proposed PEH is realized by introducing symmetric magnetic attraction to a piezoelectric cantilever beam and a pair of stoppers to confine the maximum deflection of the beam. The lumped parameter model of such a system is presented and experimentally validated. Theoretical simulations and experimental measurements demonstrate that the proposed design can bring about a wider operating bandwidth and higher output voltage than the linear PEH. Under a sinusoidal vibration with an amplitude of 3 m/s2, a 54% increase in the operating bandwidth and a 253% increase in the magnitude of output power are achieved compared to its linear counterpart. Moreover, the proposed PEH exhibits rich dynamic features, including the tunable operating bandwidth, adjustable voltage and power levels, and softening hysteresis.

Detailed study of the water trimer potential energy surface

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

Fowler, J.E.; Schaefer, H.F. III

The potential energy surface of the water trimer has been studied through the use of ab initio quantum mechanical methods. Five stationary points were located, including one minimum and two transition states. All geometries were optimized at levels up to the double-[Zeta] plus polarization plus diffuse (DZP + diff) single and double excitation coupled cluster (CCSD) level of theory. CCSD single energy points were obtained for the minimum, two transition states, and the water monomer using the triple-[Zeta] plus double polarization plus diffuse (TZ2P + diff) basis at the geometries predicted by the DZP + diff CCSD method. Reported aremore » the following: geometrical parameters, total and relative energies, harmonic vibrational frequencies and infrared intensities for the minimum, and zero point vibrational energies for the minimum, two transition states, and three separated water molecules. 27 refs., 5 figs., 10 tabs.« less

Spectrum and energy levels of kryptonlike ion Nb VI

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

Reader, J.; Ekberg, J.O.

1993-05-01

The spectrum of five-times ionized niobium, Nb, VI, was observed from 238 to 2700 {angstrom} with sliding spark discharges on 10.7-m normal- and grazing-incidence spectrographs. Experimental energies were determined for all levels of the 4s{sup 2}4p{sup 6}, 4s{sup 2}4p{sup 6}, 4s{sup 2}4p{sup 5}4d, 4f, 5s, 5p, 5g, 6s, and 4s4p{sup 6}4d configurations as well as some levels of 4p{sup 5}6g. A total of 291 lines were classified as transitions between 88 observed levels. A previous analysis of this spectrum was found to be totally erroneous. Large hyperfine splittings were found for several levels of the 4p{sup 5}5s and 5p configurations.more » The observed configurations were theoretically interpreted by means of Hartree-Fock calculations and least squares fits of the energy parameters to the observed levels. A revised value of the ionization energy was obtained from the 4p{sup 5}5g and 6g configurations.« less

Effects of Nano Additives in engine emission Characteristics using Blends of Lemon Balm oil with Diesel

NASA Astrophysics Data System (ADS)

Senthil kumar, J.; Ganesan, S.; Sivasaravanan, S.; Padmanabhan, S.; Krishnan, L.; Aniruthan, V. C.

2017-05-01

Economic growth in developing countries has led to enormous increase in energy demand. In India the energy demand is increasing at a rate of 6.5% every year. The crude oil demand of country is meet by bring in of about 70%. Thus the energy safety measures have become key issue for our country. Bio diesel an eco-friendly and renewable fuel alternate for diesel has been getting the consideration of researcher’s entire world. The main aim of this paper is to evaluate the engine parameters using blend of pure lemon balm oil with diesel. Also nano Additives is used as a catalyst with blends of bio fuel to enhance the Emission Characteristics of various effective gases like CO2, NOx, CO and UHC with various levels of engine process parameters.

Variability of textural features in FDG PET images due to different acquisition modes and reconstruction parameters.

PubMed

Galavis, Paulina E; Hollensen, Christian; Jallow, Ngoneh; Paliwal, Bhudatt; Jeraj, Robert

2010-10-01

Characterization of textural features (spatial distributions of image intensity levels) has been considered as a tool for automatic tumor segmentation. The purpose of this work is to study the variability of the textural features in PET images due to different acquisition modes and reconstruction parameters. Twenty patients with solid tumors underwent PET/CT scans on a GE Discovery VCT scanner, 45-60 minutes post-injection of 10 mCi of [(18)F]FDG. Scans were acquired in both 2D and 3D modes. For each acquisition the raw PET data was reconstructed using five different reconstruction parameters. Lesions were segmented on a default image using the threshold of 40% of maximum SUV. Fifty different texture features were calculated inside the tumors. The range of variations of the features were calculated with respect to the average value. Fifty textural features were classified based on the range of variation in three categories: small, intermediate and large variability. Features with small variability (range ≤ 5%) were entropy-first order, energy, maximal correlation coefficient (second order feature) and low-gray level run emphasis (high-order feature). The features with intermediate variability (10% ≤ range ≤ 25%) were entropy-GLCM, sum entropy, high gray level run emphsis, gray level non-uniformity, small number emphasis, and entropy-NGL. Forty remaining features presented large variations (range > 30%). Textural features such as entropy-first order, energy, maximal correlation coefficient, and low-gray level run emphasis exhibited small variations due to different acquisition modes and reconstruction parameters. Features with low level of variations are better candidates for reproducible tumor segmentation. Even though features such as contrast-NGTD, coarseness, homogeneity, and busyness have been previously used, our data indicated that these features presented large variations, therefore they could not be considered as a good candidates for tumor segmentation.

Variability of textural features in FDG PET images due to different acquisition modes and reconstruction parameters

PubMed Central

GALAVIS, PAULINA E.; HOLLENSEN, CHRISTIAN; JALLOW, NGONEH; PALIWAL, BHUDATT; JERAJ, ROBERT

2014-01-01

Background Characterization of textural features (spatial distributions of image intensity levels) has been considered as a tool for automatic tumor segmentation. The purpose of this work is to study the variability of the textural features in PET images due to different acquisition modes and reconstruction parameters. Material and methods Twenty patients with solid tumors underwent PET/CT scans on a GE Discovery VCT scanner, 45–60 minutes post-injection of 10 mCi of [18F]FDG. Scans were acquired in both 2D and 3D modes. For each acquisition the raw PET data was reconstructed using five different reconstruction parameters. Lesions were segmented on a default image using the threshold of 40% of maximum SUV. Fifty different texture features were calculated inside the tumors. The range of variations of the features were calculated with respect to the average value. Results Fifty textural features were classified based on the range of variation in three categories: small, intermediate and large variability. Features with small variability (range ≤ 5%) were entropy-first order, energy, maximal correlation coefficient (second order feature) and low-gray level run emphasis (high-order feature). The features with intermediate variability (10% ≤ range ≤ 25%) were entropy-GLCM, sum entropy, high gray level run emphsis, gray level non-uniformity, small number emphasis, and entropy-NGL. Forty remaining features presented large variations (range > 30%). Conclusion Textural features such as entropy-first order, energy, maximal correlation coefficient, and low-gray level run emphasis exhibited small variations due to different acquisition modes and reconstruction parameters. Features with low level of variations are better candidates for reproducible tumor segmentation. Even though features such as contrast-NGTD, coarseness, homogeneity, and busyness have been previously used, our data indicated that these features presented large variations, therefore they could not be considered as a good candidates for tumor segmentation. PMID:20831489

Machine Learning Force Field Parameters from Ab Initio Data

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

Li, Ying; Li, Hui; Pickard, Frank C.

Machine learning (ML) techniques with the genetic algorithm (GA) have been applied to determine a polarizable force field parameters using only ab initio data from quantum mechanics (QM) calculations of molecular clusters at the MP2/6-31G(d,p), DFMP2(fc)/jul-cc-pVDZ, and DFMP2(fc)/jul-cc-pVTZ levels to predict experimental condensed phase properties (i.e., density and heat of vaporization). The performance of this ML/GA approach is demonstrated on 4943 dimer electrostatic potentials and 1250 cluster interaction energies for methanol. Excellent agreement between the training data set from QM calculations and the optimized force field model was achieved. The results were further improved by introducing an offset factor duringmore » the machine learning process to compensate for the discrepancy between the QM calculated energy and the energy reproduced by optimized force field, while maintaining the local “shape” of the QM energy surface. Throughout the machine learning process, experimental observables were not involved in the objective function, but were only used for model validation. The best model, optimized from the QM data at the DFMP2(fc)/jul-cc-pVTZ level, appears to perform even better than the original AMOEBA force field (amoeba09.prm), which was optimized empirically to match liquid properties. The present effort shows the possibility of using machine learning techniques to develop descriptive polarizable force field using only QM data. The ML/GA strategy to optimize force fields parameters described here could easily be extended to other molecular systems.« less

Effects of chronic exposure to cadmium and temperature, alone or combined, on the threespine stickleback (Gasterosteus aculeatus): Interest of digestive enzymes as biomarkers.

PubMed

Hani, Younes Mohamed Ismail; Turies, Cyril; Palluel, Olivier; Delahaut, Laurence; Gaillet, Véronique; Bado-Nilles, Anne; Porcher, Jean-Marc; Geffard, Alain; Dedourge-Geffard, Odile

2018-06-01

The development of predictive, sensitive and reliable biomarkers is of crucial importance for aquatic biomonitoring to assess the effects of chemical substances on aquatic organisms, especially when it comes to combined effects with other stressors (e.g. temperature). The first purpose of the present study was to evaluate the single and combined effects of 90 days of exposure to an environmental cadmium concentration (0.5 μg L -1 ) and two water temperatures (16 and 21 °C) on different parameters. These parameters are involved in (i) the antioxidant system (superoxide dismutase activity -SOD- and total glutathione levels -GSH-), (ii) the energy metabolism, i.e. energy reserves (glycogen, lipids, proteins) and digestive enzymes (trypsin, amylase, intestinal alkaline phosphatase -IAP-), and (iii) biometric parameters (weight, length, Fulton's condition factor, and the gonadosomatic index -GSI-) of threespine stickleback (Gasterosteus aculeatus). The second purpose was to determine the interest of the three digestive enzymes as biomarkers in comparison with the other parameters. The higher temperature (21 °C) impacted the anti-oxidant and energy reserve parameters. In liver, GSH levels increased on day 60, while SOD decreased on days 15 and 90, with a significant decrease of protein and lipid energy reserves on day 90. In muscle, the higher temperature decreased SOD activity only on day 90. G. aculeatus biometric parameters were also impacted by the higher temperature, which limited stickleback growth after 90 days of exposure. In female sticklebacks, the GSI peaked on day 60 and decreased sharply on day 90, while the highest values were reached at day 90 in the control groups, suggesting impaired reproduction in sticklebacks raised at 21 °C. These results suggest that 21 °C is an upper-limit temperature for long-term physiological processes in sticklebacks. In contrast, very low-concentration cadmium exposure had no effect on classical biomarkers (energy reserves, antioxidant parameters, biometric parameters). However, digestive enzymes showed an interesting sensitivity to cadmium, which was emphasized by high temperature. The activity of the three digestive enzymes decreased significantly on day 90 when sticklebacks were exposed to cadmium alone, while the decrease was stronger and was recorded earlier (from day 15) when they were exposed to the cadmium-temperature combination. Compared to conventional measurements, digestive enzymes responded rapidly. This could be an important advantage for them to be used as early warning tools to reflect the health status of organisms, particularly for trypsin and IAP activities. Copyright © 2018 Elsevier B.V. All rights reserved.

A holistic approach towards defined product attributes by Maillard-type food processing.

PubMed

Davidek, Tomas; Illmann, Silke; Rytz, Andreas; Blank, Imre

2013-07-01

A fractional factorial experimental design was used to quantify the impact of process and recipe parameters on selected product attributes of extruded products (colour, viscosity, acrylamide, and the flavour marker 4-hydroxy-2,5-dimethyl-3(2H)-furanone, HDMF). The study has shown that recipe parameters (lysine, phosphate) can be used to modulate the HDMF level without changing the specific mechanical energy (SME) and consequently the texture of the product, while processing parameters (temperature, moisture) impact both HDMF and SME in parallel. Similarly, several parameters, including phosphate level, temperature and moisture, simultaneously impact both HDMF and acrylamide formation, while pH and addition of lysine showed different trends. Therefore, the latter two options can be used to mitigate acrylamide without a negative impact on flavour. Such a holistic approach has been shown as a powerful tool to optimize various product attributes upon food processing.

Two solar proton fluence models based on ground level enhancement observations

NASA Astrophysics Data System (ADS)

Raukunen, Osku; Vainio, Rami; Tylka, Allan J.; Dietrich, William F.; Jiggens, Piers; Heynderickx, Daniel; Dierckxsens, Mark; Crosby, Norma; Ganse, Urs; Siipola, Robert

2018-01-01

Solar energetic particles (SEPs) constitute an important component of the radiation environment in interplanetary space. Accurate modeling of SEP events is crucial for the mitigation of radiation hazards in spacecraft design. In this study we present two new statistical models of high energy solar proton fluences based on ground level enhancement (GLE) observations during solar cycles 19-24. As the basis of our modeling, we utilize a four parameter double power law function (known as the Band function) fits to integral GLE fluence spectra in rigidity. In the first model, the integral and differential fluences for protons with energies between 10 MeV and 1 GeV are calculated using the fits, and the distributions of the fluences at certain energies are modeled with an exponentially cut-off power law function. In the second model, we use a more advanced methodology: by investigating the distributions and relationships of the spectral fit parameters we find that they can be modeled as two independent and two dependent variables. Therefore, instead of modeling the fluences separately at different energies, we can model the shape of the fluence spectrum. We present examples of modeling results and show that the two methodologies agree well except for a short mission duration (1 year) at low confidence level. We also show that there is a reasonable agreement between our models and three well-known solar proton models (JPL, ESP and SEPEM), despite the differences in both the modeling methodologies and the data used to construct the models.

Relativistic atomic structure calculations and electron impact excitations of Fe23+

NASA Astrophysics Data System (ADS)

El-Maaref, A. A.

2016-02-01

Relativistic calculations using the multiconfiguration Dirac-Fock method for energy levels, oscillator strengths, and electronic dipole transition probabilities of Li-like iron (Fe23+) are presented. A configuration state list with the quantum numbers nl, where n = 2 - 7 and l = s , p , d , f , g , h , i has been considered. Excitations up to three electrons and correlation contributions from higher orbitals up to 7 l have been included. Contributions from core levels have been taken into account, EOL (extended optimal level) type calculations have been applied, and doubly excited levels are considered. The calculations have been executed by using the fully relativistic atomic structure package GRASP2K. The present calculations have been compared with the available experimental and theoretical sources, the comparisons show a good agreement between the present results of energy levels and oscillator strengths with the literature. In the second part of the present study, the atomic data (energy levels, and radiative parameters) have been used to calculate the excitation and deexcitation rates of allowed transitions by electron impact, as well as the population densities of some excited levels at different electron temperatures.

Design considerations for a comprehensive regional energy information system. Working paper

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

Naumann, J.D.; Knobloch, P.C.; Chervany, N.L.

1974-07-01

The Regional Energy Information System concerns itself with decision making on sub-state, state, and regional levels in emergencies, for tactical decisions, and long-range strategic policies by both government and industry. Effective access to energy information is critical, and REIS is designed to provide a standardized data base with design goals, constraints, parameters, and schedules. The REIS system is being developed now; many states, the FEA and other agencies are likewise developing energy information systems. Shareability of data must be sought, and both technical and procedural requirements for this are discussed and a plan for action is presented. (GRA)

Test of level density models from reactions of Li6 on Fe58 and Li7 on Fe57

NASA Astrophysics Data System (ADS)

Oginni, B. M.; Grimes, S. M.; Voinov, A. V.; Adekola, A. S.; Brune, C. R.; Carter, D. E.; Heinen, Z.; Jacobs, D.; Massey, T. N.; O'Donnell, J. E.; Schiller, A.

2009-09-01

The reactions of Li6 on Fe58 and Li7 on Fe57 have been studied at 15 MeV beam energy. These two reactions produce the same compound nucleus, Cu64. The charged particle spectra were measured at backward angles. The data obtained have been compared with Hauser-Feshbach model calculations. The level density parameters of Ni63 and Co60 have been obtained from the particle evaporation spectra. We also find contributions from the break up of the lithium projectiles to the low energy region of the α spectra.

New way for determining electron energy levels in quantum dots arrays using finite difference method

NASA Astrophysics Data System (ADS)

Dujardin, F.; Assaid, E.; Feddi, E.

2018-06-01

Electronic states are investigated in quantum dots arrays, depending on the type of cubic Bravais lattice (primitive, body centered or face centered) according to which the dots are arranged, the size of the dots and the interdot distance. It is shown that the ground state energy level can undergo significant variations when these parameters are modified. The results were obtained by means of finite difference method which has proved to be easily adaptable, efficient and precise. The symmetry properties of the lattice have been used to reduce the size of the Hamiltonian matrix.

Comparison of Test and Finite Element Analysis for Two Full-Scale Helicopter Crash Tests

NASA Technical Reports Server (NTRS)

Annett, Martin S.; Horta,Lucas G.

2011-01-01

Finite element analyses have been performed for two full-scale crash tests of an MD-500 helicopter. The first crash test was conducted to evaluate the performance of a composite deployable energy absorber under combined flight loads. In the second crash test, the energy absorber was removed to establish the baseline loads. The use of an energy absorbing device reduced the impact acceleration levels by a factor of three. Accelerations and kinematic data collected from the crash tests were compared to analytical results. Details of the full-scale crash tests and development of the system-integrated finite element model are briefly described along with direct comparisons of acceleration magnitudes and durations for the first full-scale crash test. Because load levels were significantly different between tests, models developed for the purposes of predicting the overall system response with external energy absorbers were not adequate under more severe conditions seen in the second crash test. Relative error comparisons were inadequate to guide model calibration. A newly developed model calibration approach that includes uncertainty estimation, parameter sensitivity, impact shape orthogonality, and numerical optimization was used for the second full-scale crash test. The calibrated parameter set reduced 2-norm prediction error by 51% but did not improve impact shape orthogonality.

Analysis of the spectrum of the (5d6+5d56s) -(5d56p+5d46s6p) transitions of two times ionized osmium (Os III)

NASA Astrophysics Data System (ADS)

Azarov, Vladimir I.; Tchang-Brillet, W.-Ü. Lydia; Gayasov, Robert R.

2018-05-01

The spectrum of osmium was observed in the (225-2100) Å wavelength region. The (5d6 + 5d56s) - (5d56p + 5d46s6p) transition array of two times ionized osmium, Os III, has been investigated and 1039 spectral lines have been classified in the region. The analysis has led to the determination of the 5d6, 5d56s, 5d56p and 5d46s6p configurations. Fifty-eight levels of the 5d6 and 5d56s configurations in the even system and 142 levels of the 5d56p and 5d46s6p configurations in the odd system have been established. The orthogonal operators technique was used to calculate the level structure and transition probabilities. The energy parameters have been determined by the least squares fit to the observed levels. Calculated transition probability and energy values, as well as LS-compositions obtained from the fitted parameters are presented.

Thermodynamic potential of free energy for thermo-elastic-plastic body

NASA Astrophysics Data System (ADS)

Śloderbach, Z.; Pająk, J.

2018-01-01

The procedure of derivation of thermodynamic potential of free energy (Helmholtz free energy) for a thermo-elastic-plastic body is presented. This procedure concerns a special thermodynamic model of a thermo-elastic-plastic body with isotropic hardening characteristics. The classical thermodynamics of irreversible processes for material characterized by macroscopic internal parameters is used in the derivation. Thermodynamic potential of free energy may be used for practical determination of the level of stored energy accumulated in material during plastic processing applied, e.g., for industry components and other machinery parts received by plastic deformation processing. In this paper the stored energy for the simple stretching of austenitic steel will be presented.

American College of Radiology-American Brachytherapy Society practice parameter for electronically generated low-energy radiation sources.

PubMed

Devlin, Phillip M; Gaspar, Laurie E; Buzurovic, Ivan; Demanes, D Jeffrey; Kasper, Michael E; Nag, Subir; Ouhib, Zoubir; Petit, Joshua H; Rosenthal, Seth A; Small, William; Wallner, Paul E; Hartford, Alan C

This collaborative practice parameter technical standard has been created between the American College of Radiology and American Brachytherapy Society to guide the usage of electronically generated low energy radiation sources (ELSs). It refers to the use of electronic X-ray sources with peak voltages up to 120 kVp to deliver therapeutic radiation therapy. The parameter provides a guideline for utilizing ELS, including patient selection and consent, treatment planning, and delivery processes. The parameter reviews the published clinical data with regard to ELS results in skin, breast, and other cancers. This technical standard recommends appropriate qualifications of the involved personnel. The parameter reviews the technical issues relating to equipment specifications as well as patient and personnel safety. Regarding suggestions for educational programs with regard to this parameter,it is suggested that the training level for clinicians be equivalent to that for other radiation therapies. It also suggests that ELS must be done using the same standards of quality and safety as those in place for other forms of radiation therapy. Copyright © 2017 American Brachytherapy Society and American College of Radiology. Published by Elsevier Inc. All rights reserved.

Effects of Taraxacum officinale on fatigue and immunological parameters in mice.

PubMed

Lee, Bo-Ra; Lee, Jong-Hyun; An, Hyo-Jin

2012-11-07

In Korean herbal medicine dandelion (Taraxacum officinale, TO) has been used to improve energy levels and health. However, the effects of TO in experimental models remain unclear. We examined the anti-fatigue and immune-enhancing effects of TO in mice by performing a forced swimming test (FST) and in vitro by using peritoneal macrophages, respectively. After daily oral administration of TO, blood biochemical parameters related to fatigue were measured after the FST. FST immobility time was significantly decreased in the TO-treated group (100 mg/kg) on the tenth day. TO (10 and 100 mg/kg) treatment significantly increased glucose levels, acting as an energy source. The level of lactic dehydrogenase, which is an accurate indicator of muscle damage, tended to decline after TO administration (10 and 100 mg/kg). When TO (100 mg/kg) was orally administered to mice, blood urea nitrogen levels decreased significantly. We also examined the effect of TO on the production of cytokines and nitric oxide (NO) in mouse peritoneal macrophages. When TO was used in combination with recombinant interferon-gamma (rIFN-γ), a noticeable cooperative induction of tumor necrosis factor-alpha (TNF-α), interleukin (IL)-12p70, and IL-10 production was observed. Furthermore, in peritoneal macrophages, rIFN-γ plus TO treatment significantly increased the production of NO through inducible nitric oxide synthase (iNOS) induction. Taken together, these results suggest that TO improves fatigue-related indicators and immunological parameters in mice.

Research on simulation system with the wide range and high-precision laser energy characteristics

NASA Astrophysics Data System (ADS)

Dong, Ke-yan; Lou, Yan; He, Jing-yi; Tong, Shou-feng; Jiang, Hui-lin

2012-10-01

The Hardware-in-the-loop(HWIL) simulation test is one of the important parts for the development and performance testing of semi-active laser-guided weapons. In order to obtain accurate results, the confidence level of the target environment should be provided for a high-seeker during the HWIL simulation test of semi-active laser-guided weapons, and one of the important simulation parameters is the laser energy characteristic. In this paper, based on the semi-active laser-guided weapon guidance principles, an important parameter of simulation of confidence which affects energy characteristics in performance test of HWIL simulation was analyzed. According to the principle of receiving the same energy by using HWIL simulation and in practical application, HWIL energy characteristics simulation systems with the crystal absorption structure was designed. And on this basis, the problems of optimal design of the optical system were also analyzed. The measured results show that the dynamic attenuation range of the system energy is greater than 50dB, the dynamic attenuation stability is less than 5%, and the maximum energy changing rate driven by the servo motor is greater than 20dB/s.

Quasiparticle-continuum level repulsion in a quantum magnet

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

Plumb, K. W.; Hwang, Kyusung; Qiu, Y.

2015-11-30

When the energy eigenvalues of two coupled quantum states approach each other in a certain parameter space, their energy levels repel each other and level crossing is avoided. Such level repulsion, or avoided level crossing, is commonly used to describe the dispersion relation of quasiparticles in solids. But, little is known about the level repulsion when more than two quasiparticles are present; for example, in a strongly interacting quantum system where a quasiparticle can spontaneously decay into a many-particle continuum. Here we show that even in this case level repulsion exists between a long-lived quasiparticle state and a continuum. Here,more » we observe a renormalization of the quasiparticle dispersion relation due to the presence of the continuum of multi-quasiparticle states, in our fine-resolution neutron spectroscopy study of magnetic quasiparticles in the frustrated quantum magnet BiCu 2PO 6.« less

Effect of anapanasati meditation technique through electrophotonic imaging parameters: A pilot study.

PubMed

Deo, Guru; Itagi R, Kumar; Thaiyar M, Srinivasan; Kuldeep, Kushwah K

2015-01-01

Mindfulness along with breathing is a well-established meditation technique. Breathing is an exquisite tool for exploring subtle awareness of mind and life itself. This study aimed at measuring changes in the different parameters of electrophotonic imaging (EPI) in anapanasati meditators. To carry out this study, 51 subjects comprising 32 males and 19 females of age 18 years and above (mean age 45.64 ± 14.43) were recruited voluntarily with informed consent attending Karnataka Dhyana Mahachakra-1 at Pyramid Valley International, Bengaluru, India. The design was a single group pre- post and data collected by EPI device before and after 5 days of intensive meditation. Results show significant changes in EPI parameter integral area with filter (physiological) in both right and left side, which reflects the availability of high functional energy reserve in meditators. The researchers observed similar trends without filter (psycho-physiological) indicating high reserves of energy at psycho-physiological level also. Activation coefficient, another parameter of EPI, reduced showing more relaxed state than earlier, possibly due to parasympathetic dominance. Integral entropy decreased in the case of psycho-physiological parameters left-side without filter, which indicates less disorder after meditation, but these changes were not significant. The study showed a reversed change in integral entropy in the right side without filter; however, the values on both sides with filter increased, which indicates disorder. The study suggests that EPI can be used in the recording functional physiological and psychophysiological status of meditators at a subtle level.

Assimilating AmeriFlux Site Data into the Community Land Model with Carbon-Nitrogen Coupling via the Ensemble Kalman Filter

NASA Astrophysics Data System (ADS)

Pettijohn, J. C.; Law, B. E.; Williams, M. D.; Stoeckli, R.; Thornton, P. E.; Hudiburg, T. M.; Thomas, C. K.; Martin, J.; Hill, T. C.

2009-12-01

The assimilation of terrestrial carbon, water and nutrient cycle measurements into land surface models of these processes is fundamental to improving our ability to predict how these ecosystems may respond to climate change. A combination of measurements and models, each with their own systematic biases, must be considered when constraining the nonlinear behavior of these coupled dynamics. As such, we use the sequential Ensemble Kalman Filter (EnKF) to assimilate eddy covariance (EC) and other site-level AmeriFlux measurements into the NCAR Community Land Model with Carbon-Nitrogen coupling (CLM-CN v3.5), run in single-column mode at a 30-minute time step, to improve estimates of relatively unconstrained model state variables and parameters. Specifically, we focus on a semi-arid ponderosa pine site (US-ME2) in the Pacific Northwest to identify the mechanisms by which this ecosystem responds to severe late summer drought. Our EnKF analysis includes water, carbon, energy and nitrogen state variables (e.g., 10 volumetric soil moisture levels (0-3.43 m), ponderosa pine and shrub evapotranspiration and net ecosystem exchange of carbon dioxide stocks and flux components, snow depth, etc.) and associated parameters (e.g., PFT-level rooting distribution parameters, maximum subsurface runoff coefficient, soil hydraulic conductivity decay factor, snow aging parameters, maximum canopy conductance, C:N ratios, etc.). The effectiveness of the EnKF in constraining state variables and associated parameters is sensitive to their relative frequencies, in that C-N state variables and parameters with long time constants require similarly long time series in the analysis. We apply the EnKF kernel perturbation routine to disrupt preliminary convergence of covariances, which has been found in recent studies to be a problem more characteristic of low frequency vegetation state variables and parameters than high frequency ones more heavily coupled with highly varying climate (e.g., shallow soil moisture, snow depth). Preliminary results demonstrate that the assimilation of EC and other available AmeriFlux site physical, chemical and biological data significantly helps quantify and reduce CLM-CN model uncertainties and helps to constrain ‘hidden’ states and parameters that are essential in the coupled water, carbon, energy and nutrient dynamics of these sites. Such site-level calibration of CLM-CN is an initial step in identifying model deficiencies and in forecasts of future ecosystem responses to climate change.

Design of a Conceptual Bumper Energy Absorber Coupling Pedestrian Safety and Low-Speed Impact Requirements

PubMed Central

Mo, Fuhao; Zhao, Siqi; Yu, Chuanhui; Duan, Shuyong

2018-01-01

The car front bumper system needs to meet the requirements of both pedestrian safety and low-speed impact which are somewhat contradicting. This study aims to design a new kind of modular self-adaptive energy absorber of the front bumper system which can balance the two performances. The X-shaped energy-absorbing structure was proposed which can enhance the energy absorption capacity during impact by changing its deformation mode based on the amount of external collision energy. Then, finite element simulations with a realistic vehicle bumper system are performed to demonstrate its crashworthiness in comparison with the traditional foam energy absorber, which presents a significant improvement of the two performances. Furthermore, the structural parameters of the X-shaped energy-absorbing structure including thickness (t u), side arc radius (R), and clamping boost beam thickness (t b) are analyzed using a full factorial method, and a multiobjective optimization is implemented regarding evaluation indexes of both pedestrian safety and low-speed impact. The optimal parameters are then verified, and the feasibility of the optimal results is confirmed. In conclusion, the new X-shaped energy absorber can meet both pedestrian safety and low-speed impact requirements well by altering the main deformation modes according to different impact energy levels. PMID:29581728

Design of a Conceptual Bumper Energy Absorber Coupling Pedestrian Safety and Low-Speed Impact Requirements.

PubMed

Mo, Fuhao; Zhao, Siqi; Yu, Chuanhui; Xiao, Zhi; Duan, Shuyong

2018-01-01

The car front bumper system needs to meet the requirements of both pedestrian safety and low-speed impact which are somewhat contradicting. This study aims to design a new kind of modular self-adaptive energy absorber of the front bumper system which can balance the two performances. The X-shaped energy-absorbing structure was proposed which can enhance the energy absorption capacity during impact by changing its deformation mode based on the amount of external collision energy. Then, finite element simulations with a realistic vehicle bumper system are performed to demonstrate its crashworthiness in comparison with the traditional foam energy absorber, which presents a significant improvement of the two performances. Furthermore, the structural parameters of the X-shaped energy-absorbing structure including thickness ( t u ), side arc radius ( R ), and clamping boost beam thickness ( t b ) are analyzed using a full factorial method, and a multiobjective optimization is implemented regarding evaluation indexes of both pedestrian safety and low-speed impact. The optimal parameters are then verified, and the feasibility of the optimal results is confirmed. In conclusion, the new X-shaped energy absorber can meet both pedestrian safety and low-speed impact requirements well by altering the main deformation modes according to different impact energy levels.

The Strength of Hydrogen Bonds between Fluoro-Organics and Alcohols, a Theoretical Study.

PubMed

Rosenberg, Robert E

2018-05-10

Fluorinated organic compounds are ubiquitous in the pharmaceutical and agricultural industries. To better discern the mode of action of these compounds, it is critical to understand the strengths of hydrogen bonds involving fluorine. There are only a few published examples of the strengths of these bonds. This study provides a high level ab initio study of inter- and intramolecular hydrogen bonds between RF and R'OH, where R and R' are aryl, vinyl, alkyl, and cycloalkyl. Intermolecular binding energies average near 5 kcal/mol, while intramolecular binding energies average about 3 kcal/mol. Inclusion of zero-point energies and applying a counterpoise correction lessen the difference. In both series, modest increases in binding energies are seen with increased acidity of R'OH and increased electron donation of R in RF. In the intramolecular compounds, binding energy increases with the rigidity of the F-(C) n -OH ring. Inclusion of free energy corrections at 298 K results in exoergic binding energies for the intramolecular compounds and endoergic binding energies for the intermolecular compounds. Parameters such as bond lengths, vibrational frequencies, and atomic populations are consistent with formation of a hydrogen bond and with slightly stronger binding in the intermolecular cases over the intramolecular cases. However, these parameters correlated poorly with binding energies.

Sensitivity analysis of a coupled hydrodynamic-vegetation model using the effectively subsampled quadratures method

USGS Publications Warehouse

Kalra, Tarandeep S.; Aretxabaleta, Alfredo; Seshadri, Pranay; Ganju, Neil K.; Beudin, Alexis

2017-01-01

Coastal hydrodynamics can be greatly affected by the presence of submerged aquatic vegetation. The effect of vegetation has been incorporated into the Coupled-Ocean-Atmosphere-Wave-Sediment Transport (COAWST) Modeling System. The vegetation implementation includes the plant-induced three-dimensional drag, in-canopy wave-induced streaming, and the production of turbulent kinetic energy by the presence of vegetation. In this study, we evaluate the sensitivity of the flow and wave dynamics to vegetation parameters using Sobol' indices and a least squares polynomial approach referred to as Effective Quadratures method. This method reduces the number of simulations needed for evaluating Sobol' indices and provides a robust, practical, and efficient approach for the parameter sensitivity analysis. The evaluation of Sobol' indices shows that kinetic energy, turbulent kinetic energy, and water level changes are affected by plant density, height, and to a certain degree, diameter. Wave dissipation is mostly dependent on the variation in plant density. Performing sensitivity analyses for the vegetation module in COAWST provides guidance for future observational and modeling work to optimize efforts and reduce exploration of parameter space.

SU-E-T-405: Evaluation of the Raystation Electron Monte Carlo Algorithm for Varian Linear Accelerators

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

Sansourekidou, P; Allen, C

2015-06-15

Purpose: To evaluate the Raystation v4.51 Electron Monte Carlo algorithm for Varian Trilogy, IX and 2100 series linear accelerators and commission for clinical use. Methods: Seventy two water and forty air scans were acquired with a water tank in the form of profiles and depth doses, as requested by vendor. Data was imported into Rayphysics beam modeling module. Energy spectrum was modeled using seven parameters. Contamination photons were modeled using five parameters. Source phase space was modeled using six parameters. Calculations were performed in clinical version 4.51 and percent depth dose curves and profiles were extracted to be compared tomore » water tank measurements. Sensitivity tests were performed for all parameters. Grid size and particle histories were evaluated per energy for statistical uncertainty performance. Results: Model accuracy for air profiles is poor in the shoulder and penumbra region. However, model accuracy for water scans is acceptable. All energies and cones are within 2%/2mm for 90% of the points evaluated. Source phase space parameters have a cumulative effect. To achieve distributions with satisfactory smoothness level a 0.1cm grid and 3,000,000 particle histories were used for commissioning calculations. Calculation time was approximately 3 hours per energy. Conclusion: Raystation electron Monte Carlo is acceptable for clinical use for the Varian accelerators listed. Results are inferior to Elekta Electron Monte Carlo modeling. Known issues were reported to Raysearch and will be resolved in upcoming releases. Auto-modeling is limited to open cone depth dose curves and needs expansion.« less

Förster-type energy transfer as a probe for changes in local fluctuations of the protein matrix.

PubMed

Somogyi, B; Matkó, J; Papp, S; Hevessy, J; Welch, G R; Damjanovich, S

1984-07-17

Much evidence, on both theoretical and experimental sides, indicates the importance of local fluctuations (in energy levels, conformational substates, etc.) of the macromolecular matrix in the biological activity of proteins. We describe here a novel application of the Förster-type energy-transfer process capable of monitoring changes both in local fluctuations and in conformational states of macromolecules. A new energy-transfer parameter, f, is defined as an average transfer efficiency, [E], normalized by the actual average quantum efficiency of the donor fluorescence, [phi D]. A simple oscillator model (for a one donor-one acceptor system) is presented to show the sensitivity of this parameter to changes in amplitudes of local fluctuations. The different modes of averaging (static, dynamic, and intermediate cases) occurring for a given value of the average transfer rate, [kt], and the experimental requirements as well as limitations of the method are also discussed. The experimental tests were performed on the ribonuclease T1-pyridoxamine 5'-phosphate conjugate (a one donor-one acceptor system) by studying the change of the f parameter with temperature, an environmental parameter expectedly perturbing local fluctuations of proteins. The parameter f increased with increasing temperature as expected on the basis of the oscillator model, suggesting that it really reflects changes of fluctuation amplitudes (significant changes in the orientation factor, k2, as well as in the spectral properties of the fluorophores can be excluded by anisotropy measurements and spectral investigations). Possibilities of the general applicability of the method are also discussed.

Detection of Cracking Levels in Brittle Rocks by Parametric Analysis of the Acoustic Emission Signals

NASA Astrophysics Data System (ADS)

Moradian, Zabihallah; Einstein, Herbert H.; Ballivy, Gerard

2016-03-01

Determination of the cracking levels during the crack propagation is one of the key challenges in the field of fracture mechanics of rocks. Acoustic emission (AE) is a technique that has been used to detect cracks as they occur across the specimen. Parametric analysis of AE signals and correlating these parameters (e.g., hits and energy) to stress-strain plots of rocks let us detect cracking levels properly. The number of AE hits is related to the number of cracks, and the AE energy is related to magnitude of the cracking event. For a full understanding of the fracture process in brittle rocks, prismatic specimens of granite containing pre-existing flaws have been tested in uniaxial compression tests, and their cracking process was monitored with both AE and high-speed video imaging. In this paper, the characteristics of the AE parameters and the evolution of cracking sequences are analyzed for every cracking level. Based on micro- and macro-crack damage, a classification of cracking levels is introduced. This classification contains eight stages (1) crack closure, (2) linear elastic deformation, (3) micro-crack initiation (white patch initiation), (4) micro-crack growth (stable crack growth), (5) micro-crack coalescence (macro-crack initiation), (6) macro-crack growth (unstable crack growth), (7) macro-crack coalescence and (8) failure.

THEORETICAL RESEARCH OF THE OPTICAL SPECTRA AND EPR PARAMETERS FOR Cs2NaYCl6:Dy3+ CRYSTAL

NASA Astrophysics Data System (ADS)

Dong, Hui-Ning; Dong, Meng-Ran; Li, Jin-Jin; Li, Deng-Feng; Zhang, Yi

2013-09-01

The calculated EPR parameters are in reasonable agreement with the observed values. The important material Cs2NaYCl6 doped with rare earth ions have received much attention because of its excellent optical and magnetic properties. Based on the superposition model, in this paper the crystal field energy levels, the electron paramagnetic resonance parameters g factors of Dy3+ and hyperfine structure constants of 161Dy3+ and 163Dy3+ isotopes in Cs2NaYCl6 crystal are studied by diagonalizing the 42 × 42 energy matrix. In the calculations, the contributions of various admixtures and interactions such as the J-mixing, the mixtures among the states with the same J-value, and the covalence are all considered. The calculated results are in reasonable agreement with the observed values. The results are discussed.

Cosmological parameter estimation from CMB and X-ray cluster after Planck

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

Hu, Jian-Wei; Cai, Rong-Gen; Guo, Zong-Kuan

We investigate constraints on cosmological parameters in three 8-parameter models with the summed neutrino mass as a free parameter, by a joint analysis of CCCP X-ray cluster data, the newly released Planck CMB data as well as some external data sets including baryon acoustic oscillation measurements from the 6dFGS, SDSS DR7 and BOSS DR9 surveys, and Hubble Space Telescope H{sub 0} measurement. We find that the combined data strongly favor a non-zero neutrino masses at more than 3σ confidence level in these non-vanilla models. Allowing the CMB lensing amplitude A{sub L} to vary, we find A{sub L} > 1 atmore » 3σ confidence level. For dark energy with a constant equation of state w, we obtain w < −1 at 3σ confidence level. The estimate of the matter power spectrum amplitude σ{sub 8} is discrepant with the Planck value at 2σ confidence level, which reflects some tension between X-ray cluster data and Planck data in these non-vanilla models. The tension can be alleviated by adding a 9% systematic shift in the cluster mass function.« less

Measurement and statistical analysis of single-molecule current-voltage characteristics, transition voltage spectroscopy, and tunneling barrier height.

PubMed

Guo, Shaoyin; Hihath, Joshua; Díez-Pérez, Ismael; Tao, Nongjian

2011-11-30

We report on the measurement and statistical study of thousands of current-voltage characteristics and transition voltage spectra (TVS) of single-molecule junctions with different contact geometries that are rapidly acquired using a new break junction method at room temperature. This capability allows one to obtain current-voltage, conductance voltage, and transition voltage histograms, thus adding a new dimension to the previous conductance histogram analysis at a fixed low-bias voltage for single molecules. This method confirms the low-bias conductance values of alkanedithiols and biphenyldithiol reported in literature. However, at high biases the current shows large nonlinearity and asymmetry, and TVS allows for the determination of a critically important parameter, the tunneling barrier height or energy level alignment between the molecule and the electrodes of single-molecule junctions. The energy level alignment is found to depend on the molecule and also on the contact geometry, revealing the role of contact geometry in both the contact resistance and energy level alignment of a molecular junction. Detailed statistical analysis further reveals that, despite the dependence of the energy level alignment on contact geometry, the variation in single-molecule conductance is primarily due to contact resistance rather than variations in the energy level alignment.

Multi-rotor internal rotations and conformational equilibria in oxiraneethanol and assignment of its vibrational spectra

NASA Astrophysics Data System (ADS)

Badawi, Hassan M.; Ali, Shaikh A.

2009-09-01

The complex internal rotations and conformational equilibria in oxiraneethanol were investigated at the DFT-B3LYP/6-311G** level of theory. Four minima were predicted in the CCOH potential energy scans of the molecule to have relative energies of about 2 kcal/mol or less and all were calculated to have real frequencies upon full optimization of structural parameters and the calculation of the Gibb's free-energies at the DFT level of calculation. At the DFT-B3LYP, the MP2 and the MP4(SDQ) levels of theory, the G1gg1 conformation, predicted to be the lowest energy conformation for oxiraneethanol, was in excellent agreement with the rotational microwave study. The equilibrium mixture was calculated to be about 47% G1gg1, 32% Cg1g, 15% Gg1t and 6% G1g1g at the B3LYP/6-311G** level of theory at 298.15 K. Solvent study corroborated the presence of the high energy Cg1g form in the liquid phase of oxiraneethanol. The vibrational frequencies of oxiraneethanol in its two stable forms were computed at the B3LYP level and vibrational assignments were made for the two lowest energy G1gg1 and Cg1g forms on the basis of calculated and experimental data of the molecule.

A Spatial Heterodyne Spectrometer for Laboratory Astrophysics; First Interferogram

NASA Technical Reports Server (NTRS)

Lawler, J. E.; Labby, Z. E.; Roesler, F. L.; Harlander, J.

2006-01-01

A Spatial Heterodyne Spectrometer with broad spectral coverage across the VUV - UV region and with a high (> 500,000 ) spectral resolving power is being built for laboratory measurements of spectroscopic data including emission branching fractions, improved level energies, and hyperfine/isotopic parameters.

dParFit: A computer program for fitting diatomic molecule spectral data to parameterized level energy expressions

NASA Astrophysics Data System (ADS)

Le Roy, Robert J.

2017-01-01

This paper describes FORTRAN program dParFit, which performs least-squares fits of diatomic molecule spectroscopic data involving one or more electronic states and one or more isotopologues, to parameterized expressions for the level energies. The data may consist of any combination of microwave, infrared or electronic vibrotational bands, fluorescence series or binding energies (from photo-association spectroscopy). The level energies for each electronic state may be described by one of: (i) band constants {Gv ,Bv ,Dv , … } for each vibrational level, (ii) generalized Dunham expansions, (iii) pure near-dissociation expansions (NDEs), (iv) mixed Dunham/NDE expressions, or (v) individual term values for each distinct level of each isotopologue. Different representations may be used for different electronic states and/or for different types of constants in a given fit (e.g., Gv and Bv may be represented one way and centrifugal distortion constants another). The effect of Λ-doubling or 2Σ splittings may be represented either by band constants (qvB or γvB, qvD or γvD, etc.) for each vibrational level of each isotopologue, or by using power series expansions in (v + 1/2) to represent those constants. Fits to Dunham or NDE expressions automatically incorporate normal first-order semiclassical mass scaling to allow combined analyses of multi-isotopologue data. In addition, dParFit may fit to determine atomic-mass-dependent terms required to account for breakdown of the Born-Oppenheimer and first-order semiclassical approximations. In any of these types of fits, one or more subsets of these parameters for one or more of the electronic states may be held fixed, while a limited parameter set is varied. The program can also use a set of read-in constants to make predictions and calculate deviations [ycalc -yobs ] for any chosen input data set, or to generate predictions of arbitrary data sets.

dPotFit: A computer program to fit diatomic molecule spectral data to potential energy functions

NASA Astrophysics Data System (ADS)

Le Roy, Robert J.

2017-01-01

This paper describes program dPotFit, which performs least-squares fits of diatomic molecule spectroscopic data consisting of any combination of microwave, infrared or electronic vibrational bands, fluorescence series, and tunneling predissociation level widths, involving one or more electronic states and one or more isotopologs, and for appropriate systems, second virial coefficient data, to determine analytic potential energy functions defining the observed levels and other properties of each state. Four families of analytical potential functions are available for fitting in the current version of dPotFit: the Expanded Morse Oscillator (EMO) function, the Morse/Long-Range (MLR) function, the Double-Exponential/Long-Range (DELR) function, and the 'Generalized Potential Energy Function' (GPEF) of Šurkus, which incorporates a variety of polynomial functional forms. In addition, dPotFit allows sets of experimental data to be tested against predictions generated from three other families of analytic functions, namely, the 'Hannover Polynomial' (or "X-expansion") function, and the 'Tang-Toennies' and Scoles-Aziz 'HFD', exponential-plus-van der Waals functions, and from interpolation-smoothed pointwise potential energies, such as those obtained from ab initio or RKR calculations. dPotFit also allows the fits to determine atomic-mass-dependent Born-Oppenheimer breakdown functions, and singlet-state Λ-doubling, or 2Σ splitting radial strength functions for one or more electronic states. dPotFit always reports both the 95% confidence limit uncertainty and the "sensitivity" of each fitted parameter; the latter indicates the number of significant digits that must be retained when rounding fitted parameters, in order to ensure that predictions remain in full agreement with experiment. It will also, if requested, apply a "sequential rounding and refitting" procedure to yield a final parameter set defined by a minimum number of significant digits, while ensuring no significant loss of accuracy in the predictions yielded by those parameters.

Constraints on a generalized deceleration parameter from cosmic chronometers

NASA Astrophysics Data System (ADS)

Mamon, Abdulla Al

2018-04-01

In this paper, we have proposed a generalized parametrization for the deceleration parameter q in order to study the evolutionary history of the universe. We have shown that the proposed model can reproduce three well known q-parametrized models for some specific values of the model parameter α. We have used the latest compilation of the Hubble parameter measurements obtained from the cosmic chronometer (CC) method (in combination with the local value of the Hubble constant H0) and the Type Ia supernova (SNIa) data to place constraints on the parameters of the model for different values of α. We have found that the resulting constraints on the deceleration parameter and the dark energy equation of state support the ΛCDM model within 1σ confidence level at the present epoch.

A partition function-based weighting scheme in force field parameter development using ab initio calculation results in global configurational space.

PubMed

Wu, Yao; Dai, Xiaodong; Huang, Niu; Zhao, Lifeng

2013-06-05

In force field parameter development using ab initio potential energy surfaces (PES) as target data, an important but often neglected matter is the lack of a weighting scheme with optimal discrimination power to fit the target data. Here, we developed a novel partition function-based weighting scheme, which not only fits the target potential energies exponentially like the general Boltzmann weighting method, but also reduces the effect of fitting errors leading to overfitting. The van der Waals (vdW) parameters of benzene and propane were reparameterized by using the new weighting scheme to fit the high-level ab initio PESs probed by a water molecule in global configurational space. The molecular simulation results indicate that the newly derived parameters are capable of reproducing experimental properties in a broader range of temperatures, which supports the partition function-based weighting scheme. Our simulation results also suggest that structural properties are more sensitive to vdW parameters than partial atomic charge parameters in these systems although the electrostatic interactions are still important in energetic properties. As no prerequisite conditions are required, the partition function-based weighting method may be applied in developing any types of force field parameters. Copyright © 2013 Wiley Periodicals, Inc.

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

Szymańska, Paulina; Martin, Katie R.; MacKeigan, Jeffrey P.

We constructed a mechanistic, computational model for regulation of (macro)autophagy and protein synthesis (at the level of translation). The model was formulated to study the system-level consequences of interactions among the following proteins: two key components of MTOR complex 1 (MTORC1), namely the protein kinase MTOR (mechanistic target of rapamycin) and the scaffold protein RPTOR; the autophagy-initiating protein kinase ULK1; and the multimeric energy-sensing AMP-activated protein kinase (AMPK). Inputs of the model include intrinsic AMPK kinase activity, which is taken as an adjustable surrogate parameter for cellular energy level or AMP:ATP ratio, and rapamycin dose, which controls MTORC1 activity. Outputsmore » of the model include the phosphorylation level of the translational repressor EIF4EBP1, a substrate of MTORC1, and the phosphorylation level of AMBRA1 (activating molecule in BECN1-regulated autophagy), a substrate of ULK1 critical for autophagosome formation. The model incorporates reciprocal regulation of mTORC1 and ULK1 by AMPK, mutual inhibition of MTORC1 and ULK1, and ULK1-mediated negative feedback regulation of AMPK. Through analysis of the model, we find that these processes may be responsible, depending on conditions, for graded responses to stress inputs, for bistable switching between autophagy and protein synthesis, or relaxation oscillations, comprising alternating periods of autophagy and protein synthesis. A sensitivity analysis indicates that the prediction of oscillatory behavior is robust to changes of the parameter values of the model. The model provides testable predictions about the behavior of the AMPK-MTORC1-ULK1 network, which plays a central role in maintaining cellular energy and nutrient homeostasis.« less

Roles of divergent and rotational winds in the kinetic energy balance during intense convective activity

NASA Technical Reports Server (NTRS)

Fuelberg, H. E.; Browning, P. A.

1983-01-01

Contributions of divergent and rotational wind components to the synoptic-scale kinetic energy balance are described using rawinsonde data at 3 and 6 h intervals from NASA's fourth Atmospheric Variability experiment. Two intense thunderstorm complexes occurred during the period. Energy budgets are described for the entire computational region and for limited volumes that enclosed storm-induced, upper level wind maxima located poleward of convection. Although small in magnitude, the divergent wind component played an important role in the cross-contour generation and horizontal flux divergence of kinetic energy. The importance of V(D) appears directly related to the presence and intensity of convection. Although K(D) usually comprised less than 10 percent of the total kinetic energy content, generation of kinetic energy by V(D) was a major factor in the creation of upper-level wind maxima to the north of the storm complexes. Omission of the divergent wind apparently would lead to serious misrepresentations of the energy balance. A random error analysis is presented to assess confidence limits in the various energy parameters.

Above scaling short-pulse ion acceleration from flat foil and ``Pizza-top Cone'' targets at the Trident laser facility

NASA Astrophysics Data System (ADS)

Flippo, Kirk; Hegelich, B. Manuel; Cort Gautier, D.; Johnson, J. Randy; Kline, John L.; Shimada, Tsutomu; Fernández, Juan C.; Gaillard, Sandrine; Rassuchine, Jennifer; Le Galloudec, Nathalie; Cowan, Thomas E.; Malekos, Steve; Korgan, Grant

2006-10-01

Ion-driven Fast Ignition (IFI) has certain advantages over electron-driven FI due to a possible large reduction in the amount of energy required. Recent experiments at the Los Alamos National Laboratory's Trident facility have yielded ion energies and efficiencies many times in excess of recent published scaling laws, leading to even more potential advantages of IFI. Proton energies in excess of 35 MeV have been observed from targets produced by the University of Nevada, Reno - dubbed ``Pizza-top Cone'' targets - at intensities of only 1x10^19 W/cm^2 with 20 joules in 600 fs. Energies in excess of 24 MeV were observed from simple flat foil targets as well. The observed energies, above any published scaling laws, are attributed to target production, preparation, and shot to shot monitoring of many laser parameters, especially the laser ASE prepulse level and laser pulse duration. The laser parameters are monitored in real-time to keep the laser in optimal condition throughout the run providing high quality, reproducible shots.

Experimental signature of collective enhancement in nuclear level density

NASA Astrophysics Data System (ADS)

Pandit, Deepak; Bhattacharya, Srijit; Mondal, Debasish; Roy, Pratap; Banerjee, K.; Mukhopadhyay, S.; Pal, Surajit; De, A.; Dey, Balaram; Banerjee, S. R.

2018-04-01

We present a probable experimental signature of collective enhancement in the nuclear level density (NLD) by measuring the neutron and the giant dipole resonance (GDR) γ rays emitted from the rare-earth 169Tm compound nucleus populated at 26.1 MeV excitation energy. An enhanced yield is observed in both neutron and γ -ray spectra corresponding to the same excitation energy in the daughter nuclei. The enhancement could only be reproduced by including a collective enhancement factor in the Fermi gas model of NLD to explain the neutron and GDR spectra simultaneously. The experimental results show that the relative enhancement factor is of the order of 10 and the fadeout occurs at ˜14 MeV excitation energy, much before the commonly accepted transition from deformed to spherical shape. We also explain how the collective enhancement contribution changes the inverse level density parameter k from 8 to 9.5 MeV observed recently in several deformed nuclei.

Noble-TLBO MPPT Technique and its Comparative Analysis with Conventional methods implemented on Solar Photo Voltaic System

NASA Astrophysics Data System (ADS)

Patsariya, Ajay; Rai, Shiwani; Kumar, Yogendra, Dr.; Kirar, Mukesh, Dr.

2017-08-01

The energy crisis particularly with developing GDPs, has bring up to a new panorama of sustainable power source like solar energy, which has encountered huge development. Progressively high infiltration level of photovoltaic (PV) era emerges in keen matrix. Sunlight based power is irregular and variable, as the sun based source at the ground level is exceedingly subject to overcast cover inconstancy, environmental vaporized levels, and other climate parameters. The inalienable inconstancy of substantial scale sun based era acquaints huge difficulties with keen lattice vitality administration. Exact determining of sun powered power/irradiance is basic to secure financial operation of the shrewd framework. In this paper a noble TLBO-MPPT technique has been proposed to address the vitality of solar energy. A comparative analysis has been presented between conventional PO, IC and the proposed MPPT technique. The research has been done on Matlab Simulink software version 2013.

Effect of low-level laser-treated mesenchymal stem cells on myocardial infarction.

PubMed

El Gammal, Zaynab H; Zaher, Amr M; El-Badri, Nagwa

2017-09-01

Cardiovascular disease is the leading cause of death worldwide. Although cardiac transplantation is considered the most effective therapy for end-stage cardiac diseases, it is limited by the availability of matching donors and the complications of the immune suppressive regimen used to prevent graft rejection. Application of stem cell therapy in experimental animal models was shown to reverse cardiac remodeling, attenuate cardiac fibrosis, improve heart functions, and stimulate angiogenesis. The efficacy of stem cell therapy can be amplified by low-level laser radiation. It is well established that the bio-stimulatory effect of low-level laser is influenced by the following parameters: wavelength, power density, duration, energy density, delivery time, and the type of irradiated target. In this review, we evaluate the available experimental data on treatment of myocardial infarction using low-level laser. Eligible papers were characterized as in vivo experimental studies that evaluated the use of low-level laser therapy on stem cells in order to attenuate myocardial infarction. The following descriptors were used separately and in combination: laser therapy, low-level laser, low-power laser, stem cell, and myocardial infarction. The assessed low-level laser parameters were wavelength (635-804 nm), power density (6-50 mW/cm 2 ), duration (20-150 s), energy density (0.96-1 J/cm 2 ), delivery time (20 min-3 weeks after myocardial infarction), and the type of irradiated target (bone marrow or in vitro-cultured bone marrow mesenchymal stem cells). The analysis focused on the cardioprotective effect of this form of therapy, the attenuation of scar tissue, and the enhancement of angiogenesis as primary targets. Other effects such as cell survival, cell differentiation, and homing are also included. Among the evaluated protocols using different parameters, the best outcome for treating myocardial infarction was achieved by treating the bone marrow by one dose of low-level laser with 804 nm wavelength and 1 J/cm 2 energy density within 4 h of the infarction. This approach increased stem cell survival, proliferation, and homing. It has also decreased the infarct size and cell apoptosis, leading to enhanced heart functions. These effects were stable for 6 weeks. However, more studies are still required to assess the effects of low-level laser on the genetic makeup of the cell, the nuclei, and the mitochondria of mesenchymal stromal cells (MSCs).

Low-energy tautomers and conformers of neutral and protonated arginine.

PubMed

Rak, J; Skurski, P; Simons, J; Gutowski, M

2001-11-28

The relative stabilities of zwitterionic and canonical forms of neutral arginine and of its protonated derivative were studied by using ab initio electronic structure methods. Trial structures were first identified at the PM3 level of theory with use of a genetic algorithm to systematically vary geometrical parameters. Further geometry optimizations of these structures were performed at the MP2 and B3LYP levels of theory with basis sets of the 6-31++G** quality. The final energies were determined at the CCSD/6-31++G** level and corrected for thermal effects determined at the B3LYP level. Two new nonzwitterionic structures of the neutral were identified, and one of them is the lowest energy structure found so far. The five lowest energy structures of neutral arginine are all nonzwitterionic in nature and are clustered within a narrow energy range of 2.3 kcal/mol. The lowest energy zwitterion structure is less stable than the lowest nonzwitterion structure by 4.0 kcal/mol. For no level of theory is a zwitterion structure suggested to be the global minimum. The calculated proton affinity of 256.3 kcal/mol and gas-phase basicity of 247.8 kcal/mol of arginine are in reasonable agreement with the measured values of 251.2 and 240.6 kcal/mol, respectively. The calculated vibrational characteristics of the low-energy structures of neutral arginine provide an alternative interpretation of the IR-CRLAS spectrum (Chapo et al. J. Am. Chem. Soc. 1998, 120, 12956-12957).

Visible luminescence of Dy3+ doped PbF2-Li2O-SrO-ZnO-B2O3 glasses for yellow light applications

NASA Astrophysics Data System (ADS)

Anjaiah, G.; Sasikala, T.; Kistaiah, P.

2018-05-01

The present studies on various concentrations of Dy3+ ions doped PLSrZFB glasses were carried out through optical absorption, photoluminescence and decay time measurements. The Judd-Ofelt (JO) intensity parameters Ωλ (λ = 2,4,6) can be utilized to evaluate the emission properties. The decay curves for the 4F9/2 levels have been measured and these turns to non-exponential nature at higher concentrations (> 0.1 mol%) is due to energy transfer between the Dy3+-Dy3+ ions dipole -dipole type through cross relaxation channels. The CIE chromaticity color coordinates were calculated and they were all located within the vicinity of white region of the color coordination diagram. The Inokuti-Hirayama model is used to analyze the energy transfer process and also energy transfer parameters have been calculated and discussed.

Theoretical Studies on Structures and Relative Stability for Polynitrohexaazaadamantanes

NASA Astrophysics Data System (ADS)

Xu, Xiao-juan; Xiao, He-ming; Wang, Gui-xiang; Ju, Xue-hai

2006-10-01

The density function theory at the B3LYP/6-31G* level was employed to study the structures, including the total energies (EZPE), the geometries, the oxygen balances (OB100), the dipole moments, of polynitro-hexaazaadamantanes (PNHAAs) and the potential candidates of high energy density compounds (HEDCs). The structural parameters of PNHAAs, such as the the maximum N—NO2 bond length (LBmax), the least N—N Mulliken population (BN—N), the least negative charge on the nitro group (QNO2) and OB100, were studied to predict their relative stability or sensitivity (the easiness for initiating a detonation, high sensitivity means low stability). It was found that the same conclusion was drawn from the four parameters. With the number of nitro groups increasing, the stabilities of these compounds decrease. OB100 failed in identifying the isomers, but the EZPE energy and the dipole moment were considered to give more reliable results for the isomers.

Echo of interactions in the dark sector

NASA Astrophysics Data System (ADS)

Kumar, Suresh; Nunes, Rafael C.

2017-11-01

We investigate the observational constraints on an interacting vacuum energy scenario with two different neutrino schemes (with and without a sterile neutrino) using the most recent data from cosmic microwave background (CMB) temperature and polarization anisotropy, baryon acoustic oscillations (BAO), type Ia supernovae from JLA sample and structure growth inferred from cluster counts. We find that inclusion of the galaxy clusters data with the minimal data combination CMB +BAO +JLA suggests an interaction in the dark sector, implying the decay of dark matter particles into dark energy, since the constraints obtained by including the galaxy clusters data yield a non-null and negative coupling parameter between the dark components at 99% confidence level. We deduce that the current tensions on the parameters H0 and σ8 can be alleviated within the framework of the interacting as well as noninteracting vacuum energy models with sterile neutrinos.

High energy efficiency and high power density proton exchange membrane fuel cells: Electrode kinetics and mass transport

NASA Technical Reports Server (NTRS)

Srinivasan, Supramaniam; Velev, Omourtag A.; Parthasathy, Arvind; Manko, David J.; Appleby, A. John

1991-01-01

The development of proton exchange membrane (PEM) fuel cell power plants with high energy efficiencies and high power densities is gaining momentum because of the vital need of such high levels of performance for extraterrestrial (space, underwater) and terrestrial (power source for electric vehicles) applications. Since 1987, considerable progress has been made in achieving energy efficiencies of about 60 percent at a current density of 200 mA/sq cm and high power densities (greater than 1 W/sq cm) in PEM fuel cells with high (4 mg/sq cm) or low (0.4 mg/sq cm) platinum loadings in electrodes. The following areas are discussed: (1) methods to obtain these high levels of performance with low Pt loading electrodes - by proton conductor impregnation into electrodes, localization of Pt near front surface; (2) a novel microelectrode technique which yields electrode kinetic parameters for oxygen reduction and mass transport parameters; (3) demonstration of lack of water transport from anode to cathode; (4) modeling analysis of PEM fuel cell for comparison with experimental results and predicting further improvements in performance; and (5) recommendations of needed research and development for achieving the above goals.

High-energy infrared femtosecond pulses generated by dual-chirped optical parametric amplification.

PubMed

Fu, Yuxi; Takahashi, Eiji J; Midorikawa, Katsumi

2015-11-01

We demonstrate high-energy infrared femtosecond pulse generation by a dual-chirped optical parametric amplification (DC-OPA) scheme [Opt. Express19, 7190 (2011)]. By employing a 100 mJ pump laser, a signal pulse energy exceeding 20 mJ at a wavelength of 1.4 μm was achieved before dispersion compensation. A total output energy of 33 mJ was recorded. Under a further energy scaling condition, the signal pulse was compressed to an almost transform-limited duration of 27 fs using a fused silica prism compressor. Since the DC-OPA scheme is efficient and energy scalable, design parameters for obtaining 100 mJ level infrared pulses are presented, which are suitable as driver lasers for the energy scaling of high-order harmonic generation with sub-keV photon energy.

Understanding the effects of electromagnetic field emissions from Marine Renewable Energy Devices (MREDs) on the commercially important edible crab, Cancer pagurus (L.).

PubMed

Scott, Kevin; Harsanyi, Petra; Lyndon, Alastair R

2018-06-01

The effects of simulated electromagnetic fields (EMF), emitted from sub-sea power cables, on the commercially important decapod, edible crab (Cancer pagurus), were assessed. Stress related parameters were measured (l-Lactate, d-Glucose, Haemocyanin and respiration rate) along with behavioural and response parameters (antennular flicking, activity level, attraction/avoidance, shelter preference and time spent resting/roaming) during 24-h periods. Exposure to EMF had no effect on Haemocyanin concentrations, respiration rate, activity level or antennular flicking rate. EMF exposure significantly disrupted haemolymph l-Lactate and d-Glucose natural circadian rhythms. Crabs showed a clear attraction to EMF exposed shelter (69%) compared to control shelter (9%) and significantly reduced their time spent roaming by 21%. Consequently, EMF emitted from Marine Renewable Energy Devices (MREDs) will likely affect edible crabs both behaviourally and physiologically, suggesting that the impact of EMF on crustaceans must be considered when planning MREDs. Copyright © 2018 Elsevier Ltd. All rights reserved.

Synergistic Effects of Temperature, Oxidation and Stress Level on Fatigue Damage Evolution and Lifetime Prediction of Cross-Ply SiC/CAS Ceramic-Matrix Composites Through Hysteresis-Based Parameters

NASA Astrophysics Data System (ADS)

Li, Longbiao

2017-12-01

The damage development and cyclic fatigue lifetime of cross-ply SiC/CAS ceramic-matrix composites have been investigated at different testing temperatures in air atmosphere. The relationships between the fatigue hysteresis-based damage parameters, i.e., fatigue hysteresis dissipated energy, fatigue hysteresis modulus and fatigue peak strain and the damage mechanisms of matrix multicracking, fiber/matrix interface debonding, interface sliding and fibers failure, have been established. With the increase in the cycle number, the evolution of the fatigue hysteresis modulus, fatigue peak strain and fatigue hysteresis dissipated energy depends upon the fatigue peak stress levels, interface and fibers oxidation and testing temperature. The fatigue life S-N curves of cross-ply SiC/CAS composite at room and elevated temperatures have been predicted, and the fatigue limit stresses at room temperature, 750 and 850 °C, are 50, 36 and 30% of the tensile strength, respectively.

Effect of broken axial symmetry on the electric dipole strength and the collective enhancement of level densities in heavy nuclei

NASA Astrophysics Data System (ADS)

Grosse, E.; Junghans, A. R.; Wilson, J. N.

2017-11-01

The basic parameters for calculations of radiative neutron capture, photon strength functions and nuclear level densities near the neutron separation energy are determined based on experimental data without an ad hoc assumption about axial symmetry—at variance to previous analysis. Surprisingly few global fit parameters are needed in addition to information on nuclear deformation, taken from Hartree Fock Bogolyubov calculations with the Gogny force, and the generator coordinator method assures properly defined angular momentum. For a large number of nuclei the GDR shapes and the photon strength are described by the sum of three Lorentzians, extrapolated to low energies and normalised in accordance to the dipole sum rule. Level densities are influenced strongly by the significant collective enhancement based on the breaking of shape symmetry. The replacement of axial symmetry by the less stringent requirement of invariance against rotation by 180° leads to a novel prediction for radiative neutron capture. It compares well to recent compilations of average radiative widths and Maxwellian average cross sections for neutron capture by even target nuclei. An extension to higher spin promises a reliable prediction for various compound nuclear reactions also outside the valley of stability. Such predictions are of high importance for future nuclear energy systems and waste transmutation as well as for the understanding of the cosmic synthesis of heavy elements.

Improved cosmological constraints on the curvature and equation of state of dark energy

NASA Astrophysics Data System (ADS)

Pan, Nana; Gong, Yungui; Chen, Yun; Zhu, Zong-Hong

2010-08-01

We apply the Constitution compilation of 397 supernova Ia, the baryon acoustic oscillation measurements including the A parameter, the distance ratio and the radial data, the five-year Wilkinson microwave anisotropy probe and the Hubble parameter data to study the geometry of the Universe and the property of dark energy by using the popular Chevallier-Polarski-Linder and Jassal-Bagla-Padmanabhan parameterizations. We compare the simple χ2 method of joined contour estimation and the Monte Carlo Markov chain method, and find that it is necessary to make the marginalized analysis on the error estimation. The probabilities of Ωk and wa in the Chevallier-Polarski-Linder model are skew distributions, and the marginalized 1σ errors are Ωm = 0.279+0.015- 0.008, Ωk = 0.005+0.006- 0.011, w0 = -1.05+0.23- 0.06 and wa = 0.5+0.3- 1.5. For the Jassal-Bagla-Padmanabhan model, the marginalized 1σ errors are Ωm = 0.281+0.015- 0.01, Ωk = 0.000+0.007- 0.006, w0 = -0.96+0.25- 0.18 and wa = -0.6+1.9- 1.6. The equation of state parameter w(z) of dark energy is negative in the redshift range 0 <= z <= 2 at more than 3σ level. The flat ΛCDM model is consistent with the current observational data at the 1σ level.

Crashworthiness of Aluminium Tubes; Part 2: Improvement of Hydroforming Operation to Increase Absorption Energy

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

D'Amours, Guillaume; Rahem, Ahmed; Mayer, Robert

2007-05-17

The motivation to reduce overall vehicle weight within the automotive sector drives the substitution of lightweight materials such as aluminium alloys for structural components. Such a substitution requires a significant amount of development to manufacture structurally parts such that the energy absorption characteristics are not sacrificed in the event of crash. The effects of the manufacturing processes on the crash performance of automotive structural components must be better understood to ensure improved crashworthiness. This paper presents results of an experimental and numerical investigation of the crash response and energy absorption properties of impacted hydroformed aluminium alloy tubes. Crash experiments onmore » hydroformed tubes were performed using a deceleration sled test at the General Motors Technical Center. Results from axial crush testing showed that an important parameter that influences the energy absorption characteristics during crash was the thickness reduction caused by circumferential expansion of the tube during hydroforming. It was found that that the energy absorption decreased as the corner radius decreased, which results because of increased thinning. Sensitivity studies of end feeding parameters, such as end feed level and profile, were carried out to evaluate their impact on the energy absorption of the aluminium tubes.« less

Crashworthiness of Aluminium Tubes; Part 2: Improvement of Hydroforming Operation to Increase Absorption Energy

NASA Astrophysics Data System (ADS)

D'Amours, Guillaume; Rahem, Ahmed; Mayer, Robert; Williams, Bruce; Worswick, Michael

2007-05-01

The motivation to reduce overall vehicle weight within the automotive sector drives the substitution of lightweight materials such as aluminium alloys for structural components. Such a substitution requires a significant amount of development to manufacture structurally parts such that the energy absorption characteristics are not sacrificed in the event of crash. The effects of the manufacturing processes on the crash performance of automotive structural components must be better understood to ensure improved crashworthiness. This paper presents results of an experimental and numerical investigation of the crash response and energy absorption properties of impacted hydroformed aluminium alloy tubes. Crash experiments on hydroformed tubes were performed using a deceleration sled test at the General Motors Technical Center. Results from axial crush testing showed that an important parameter that influences the energy absorption characteristics during crash was the thickness reduction caused by circumferential expansion of the tube during hydroforming. It was found that that the energy absorption decreased as the corner radius decreased, which results because of increased thinning. Sensitivity studies of end feeding parameters, such as end feed level and profile, were carried out to evaluate their impact on the energy absorption of the aluminium tubes.

The spectrum of singly ionized tungsten

NASA Astrophysics Data System (ADS)

Husain, Abid; Jabeen, S.; Wajid, Abdul

2018-05-01

The ab initio calculations were performed using Cowan's computer code for ground configuration5d46s incorporating other interacting even parity configurations 5d36s2 and 5d5, also for the three lowest excited configurations5d46p, 5d36s6p and 5d36s5f of odd parity matrix. The initial energy parameter scaling applied for Eav and ζ at 100% of the HFR values and Fk at 85%, Gk and Rk at 75% of the HFR values. The reported values of levels were taken from NIST ASD levels list. The levels were used to run least square fitted (LSF). This allowed adjusting the energy to the real values and hence a better prediction was achieved.

Towards the effect of acoustic emission (AE) sensor positioning within AE signal parameters in sliding on bulk ultrafine-grained materials

NASA Astrophysics Data System (ADS)

Filippov, A. V.; Tarasov, S. Yu.; Podgornykh, O. A.; Chazov, P. A.; Shamarin, N. N.; Filippova, E. O.

2017-12-01

The effect of AE sensor positioning on the bulk ultrafine-grained materials used for sliding against steel ball has been investigated. Two versions of AE sensor positioning have been tested and showed the different attenuation levels. The experimentally obtained AE signal waveforms have been analyzed under the AE signal parameters such as a median frequency and AE energy. It was established that the AE sensor positioned on the sample supporting plate in the vicinity of the sample tested allowed redistribution of the signal energy from a low-frequency to high-frequency range as well as extending the median frequency range as compared to those obtained by mounting the sensor on the immobile sample holder.

Systematic effects on dark energy from 3D weak shear

NASA Astrophysics Data System (ADS)

Kitching, T. D.; Taylor, A. N.; Heavens, A. F.

2008-09-01

We present an investigation into the potential effect of systematics inherent in multiband wide-field surveys on the dark energy equation-of-state determination for two 3D weak lensing methods. The weak lensing methods are a geometric shear-ratio method and 3D cosmic shear. The analysis here uses an extension of the Fisher matrix framework to include jointly photometric redshift systematics, shear distortion systematics and intrinsic alignments. Using analytic parametrizations of these three primary systematic effects allows an isolation of systematic parameters of particular importance. We show that assuming systematic parameters are fixed, but possibly biased, results in potentially large biases in dark energy parameters. We quantify any potential bias by defining a Bias Figure of Merit. By marginalizing over extra systematic parameters, such biases are negated at the expense of an increase in the cosmological parameter errors. We show the effect on the dark energy Figure of Merit of marginalizing over each systematic parameter individually. We also show the overall reduction in the Figure of Merit due to all three types of systematic effects. Based on some assumption of the likely level of systematic errors, we find that the largest effect on the Figure of Merit comes from uncertainty in the photometric redshift systematic parameters. These can reduce the Figure of Merit by up to a factor of 2 to 4 in both 3D weak lensing methods, if no informative prior on the systematic parameters is applied. Shear distortion systematics have a smaller overall effect. Intrinsic alignment effects can reduce the Figure of Merit by up to a further factor of 2. This, however, is a worst-case scenario, within the assumptions of the parametrizations used. By including prior information on systematic parameters, the Figure of Merit can be recovered to a large extent, and combined constraints from 3D cosmic shear and shear ratio are robust to systematics. We conclude that, as a rule of thumb, given a realistic current understanding of intrinsic alignments and photometric redshifts, then including all three primary systematic effects reduces the Figure of Merit by at most a factor of 2.

Surveying implicit solvent models for estimating small molecule absolute hydration free energies

PubMed Central

Knight, Jennifer L.

2011-01-01

Implicit solvent models are powerful tools in accounting for the aqueous environment at a fraction of the computational expense of explicit solvent representations. Here, we compare the ability of common implicit solvent models (TC, OBC, OBC2, GBMV, GBMV2, GBSW, GBSW/MS, GBSW/MS2 and FACTS) to reproduce experimental absolute hydration free energies for a series of 499 small neutral molecules that are modeled using AMBER/GAFF parameters and AM1-BCC charges. Given optimized surface tension coefficients for scaling the surface area term in the nonpolar contribution, most implicit solvent models demonstrate reasonable agreement with extensive explicit solvent simulations (average difference 1.0-1.7 kcal/mol and R2=0.81-0.91) and with experimental hydration free energies (average unsigned errors=1.1-1.4 kcal/mol and R2=0.66-0.81). Chemical classes of compounds are identified that need further optimization of their ligand force field parameters and others that require improvement in the physical parameters of the implicit solvent models themselves. More sophisticated nonpolar models are also likely necessary to more effectively represent the underlying physics of solvation and take the quality of hydration free energies estimated from implicit solvent models to the next level. PMID:21735452

Theoretical study of the dependence of single impurity Anderson model on various parameters within distributional exact diagonalization method

NASA Astrophysics Data System (ADS)

Syaina, L. P.; Majidi, M. A.

2018-04-01

Single impurity Anderson model describes a system consisting of non-interacting conduction electrons coupled with a localized orbital having strongly interacting electrons at a particular site. This model has been proven successful to explain the phenomenon of metal-insulator transition through Anderson localization. Despite the well-understood behaviors of the model, little has been explored theoretically on how the model properties gradually evolve as functions of hybridization parameter, interaction energy, impurity concentration, and temperature. Here, we propose to do a theoretical study on those aspects of a single impurity Anderson model using the distributional exact diagonalization method. We solve the model Hamiltonian by randomly generating sampling distribution of some conducting electron energy levels with various number of occupying electrons. The resulting eigenvalues and eigenstates are then used to define the local single-particle Green function for each sampled electron energy distribution using Lehmann representation. Later, we extract the corresponding self-energy of each distribution, then average over all the distributions and construct the local Green function of the system to calculate the density of states. We repeat this procedure for various values of those controllable parameters, and discuss our results in connection with the criteria of the occurrence of metal-insulator transition in this system.

Modelling non-linear effects of dark energy

NASA Astrophysics Data System (ADS)

Bose, Benjamin; Baldi, Marco; Pourtsidou, Alkistis

2018-04-01

We investigate the capabilities of perturbation theory in capturing non-linear effects of dark energy. We test constant and evolving w models, as well as models involving momentum exchange between dark energy and dark matter. Specifically, we compare perturbative predictions at 1-loop level against N-body results for four non-standard equations of state as well as varying degrees of momentum exchange between dark energy and dark matter. The interaction is modelled phenomenologically using a time dependent drag term in the Euler equation. We make comparisons at the level of the matter power spectrum and the redshift space monopole and quadrupole. The multipoles are modelled using the Taruya, Nishimichi and Saito (TNS) redshift space spectrum. We find perturbation theory does very well in capturing non-linear effects coming from dark sector interaction. We isolate and quantify the 1-loop contribution coming from the interaction and from the non-standard equation of state. We find the interaction parameter ξ amplifies scale dependent signatures in the range of scales considered. Non-standard equations of state also give scale dependent signatures within this same regime. In redshift space the match with N-body is improved at smaller scales by the addition of the TNS free parameter σv. To quantify the importance of modelling the interaction, we create mock data sets for varying values of ξ using perturbation theory. This data is given errors typical of Stage IV surveys. We then perform a likelihood analysis using the first two multipoles on these sets and a ξ=0 modelling, ignoring the interaction. We find the fiducial growth parameter f is generally recovered even for very large values of ξ both at z=0.5 and z=1. The ξ=0 modelling is most biased in its estimation of f for the phantom w=‑1.1 case.

Refrigeration generation using expander-generator units

NASA Astrophysics Data System (ADS)

Klimenko, A. V.; Agababov, V. S.; Koryagin, A. V.; Baidakova, Yu. O.

2016-05-01

The problems of using the expander-generator unit (EGU) to generate refrigeration, along with electricity were considered. It is shown that, on the level of the temperatures of refrigeration flows using the EGU, one can provide the refrigeration supply of the different consumers: ventilation and air conditioning plants and industrial refrigerators and freezers. The analysis of influence of process parameters on the cooling power of the EGU, which depends on the parameters of the gas expansion process in the expander and temperatures of cooled environment, was carried out. The schematic diagram of refrigeration generation plant based on EGU is presented. The features and advantages of EGU to generate refrigeration compared with thermotransformer of steam compressive and absorption types were shown, namely: there is no need to use the energy generated by burning fuel to operate the EGU; beneficial use of the heat delivered to gas from the flow being cooled in equipment operating on gas; energy production along with refrigeration generation, which makes it possible to create, using EGU, the trigeneration plants without using the energy power equipment. It is shown that the level of the temperatures of refrigeration flows, which can be obtained by using the EGU on existing technological decompression stations of the transported gas, allows providing the refrigeration supply of various consumers. The information that the refrigeration capacity of an expander-generator unit not only depends on the parameters of the process of expansion of gas flowing in the expander (flow rate, temperatures and pressures at the inlet and outlet) but it is also determined by the temperature needed for a consumer and the initial temperature of the flow of the refrigeration-carrier being cooled. The conclusion was made that the expander-generator units can be used to create trigeneration plants both at major power plants and at small energy.

Serum Irisin and Oxytocin Levels as Predictors of Metabolic Parameters in Obese Children.

PubMed

Binay, Çiğdem; Paketçi, Cem; Güzel, Savaş; Samancı, Nedim

2017-06-01

Irisin and oxytocin can affect energy homeostasis and it has been suggested that they may play an important role in reducing obesity and diabetes. In this study, we aimed to determine the relationship between metabolic parameters (including irisin and oxytocin levels) and anthropometric parameters in obese children. Ninety obese children (mean age, 13.85±1.63 years) and 30 healthy controls (mean age, 14.32±1.58 years) were enrolled in this study. Anthropometric and laboratory parameters (glucose, insulin, lipid, oxytocin, and irisin levels) were analyzed. The serum irisin and oxytocin levels were measured by enzyme-linked immunosorbent assay. Bioelectrical impedance was used to determine body composition. Irisin level was higher in the patients than in the controls (p=0.018), and this higher irisin level was correlated with increased systolic blood pressure, body mass index, waist/hip ratio, fat percentage, fat mass, glucose level, insulin level, and homeostasis model assessment of insulin resistance. Serum oxytocin level was significantly decreased in obese children compared to the controls (p=0.049). Also, among the 60 obese patients, oxytocin level was significantly lower in patients with than in those without metabolic syndrome (8.65±2.69 vs. 10.87±5.93 ng/L, respectively), while irisin levels were comparable (p=0.049 and p=0.104, respectively). There were no statistically significant relationships between oxytocin or irisin levels and lipid levels (p>0.05). Obese children had significantly higher irisin levels than the healthy controls. Additionally, this study shows for the first time that oxytocin level is significantly lower in obese compared with non-obese children and also lower in obese children with metabolic syndrome compared to those without.

Energy sources and levels influenced on performance parameters, thyroid hormones, and HSP70 gene expression of broiler chickens under heat stress.

PubMed

Raghebian, Majid; Sadeghi, Ali Asghar; Aminafshar, Mehdi

2016-12-01

The present study was conducted to evaluate the effects of energy sources and levels on body and organs weights, thyroid hormones, and heat shock protein (HSP70) gene expression in broilers under heat stress. In a completely randomized design, 600 1-day-old Cobb chickens were assigned to five dietary treatments and four replicates. The chickens were fed diet based on corn as main energy source and energy level based on Cobb standard considered as control (C), corn-based diet with 3 % lesser energy than the control (T1), corn-based diet with 6 % lesser energy than the control (T2), corn and soybean oil-based diet according to Cobb standard (T3), and corn and soybean oil-based diet with 3 % upper energy than the control (T4). Temperature was increased to 34 °C for 8 h daily from days 12 to 41 of age to induce heat stress. The chickens in T1 and T2 had lower thyroid hormones and corticosterone levels than those in C, T3, and T4. The highest liver weight was for C and the lowest one was for T4. The highest gene expression was found in chickens fed T4 diet, and the lowest gene expression was for those in T2 group. The highest feed intake and worse feed conversion ratio was related to chickens in T2. The chickens in T3 and T4 had higher feed intake and weight gain than those in C. The results showed that the higher energy level supplied from soybean oil could enhance gene expression of HSP70 and decline the level of corticosterone and thyroid hormones and consequently improved performance.

Puckering transitions in cyclohexane: Revisited

NASA Astrophysics Data System (ADS)

Kang, Young Kee; Park, Hae Sook

2018-06-01

The interconversion pathways along the puckering transitions in cyclohexane were explored on the two-dimensional projection of the Cremer-Pople sphere using DFT methods and the CCSD(T), MP2, and dispersion-corrected DFT methods with various basis sets were assessed for the relative energies of local minima and transition states for the representative puckering transition pathways. The ωB97X-D/cc-pVTZ and ωB97X-D/def2-QZVP levels of theory well reproduced the relative energies with RMSD = 0.13 kcal/mol against the CCSD(T)/CBS-limit energies. The calculated activation parameters for chair to twist-boat interconversion of cyclohexane at the ωB97X-D/cc-pVTZ//(PCM) M06-2X/6-31+G(d) level of theory were consistent with the observed values.

Stochastic dark energy from inflationary quantum fluctuations

NASA Astrophysics Data System (ADS)

Glavan, Dražen; Prokopec, Tomislav; Starobinsky, Alexei A.

2018-05-01

We study the quantum backreaction from inflationary fluctuations of a very light, non-minimally coupled spectator scalar and show that it is a viable candidate for dark energy. The problem is solved by suitably adapting the formalism of stochastic inflation. This allows us to self-consistently account for the backreaction on the background expansion rate of the Universe where its effects are large. This framework is equivalent to that of semiclassical gravity in which matter vacuum fluctuations are included at the one loop level, but purely quantum gravitational fluctuations are neglected. Our results show that dark energy in our model can be characterized by a distinct effective equation of state parameter (as a function of redshift) which allows for testing of the model at the level of the background.

Deformed supersymmetric quantum mechanics with spin variables

NASA Astrophysics Data System (ADS)

Fedoruk, Sergey; Ivanov, Evgeny; Sidorov, Stepan

2018-01-01

We quantize the one-particle model of the SU(2|1) supersymmetric multiparticle mechanics with the additional semi-dynamical spin degrees of freedom. We find the relevant energy spectrum and the full set of physical states as functions of the mass-dimension deformation parameter m and SU(2) spin q\\in (Z_{>0,}1/2+Z_{≥0}) . It is found that the states at the fixed energy level form irreducible multiplets of the supergroup SU(2|1). Also, the hidden superconformal symmetry OSp(4|2) of the model is revealed in the classical and quantum cases. We calculate the OSp(4|2) Casimir operators and demonstrate that the full set of the physical states belonging to different energy levels at fixed q are unified into an irreducible OSp(4|2) multiplet.

QM/MM free energy simulations: recent progress and challenges

PubMed Central

Lu, Xiya; Fang, Dong; Ito, Shingo; Okamoto, Yuko; Ovchinnikov, Victor

2016-01-01

Due to the higher computational cost relative to pure molecular mechanical (MM) simulations, hybrid quantum mechanical/molecular mechanical (QM/MM) free energy simulations particularly require a careful consideration of balancing computational cost and accuracy. Here we review several recent developments in free energy methods most relevant to QM/MM simulations and discuss several topics motivated by these developments using simple but informative examples that involve processes in water. For chemical reactions, we highlight the value of invoking enhanced sampling technique (e.g., replica-exchange) in umbrella sampling calculations and the value of including collective environmental variables (e.g., hydration level) in metadynamics simulations; we also illustrate the sensitivity of string calculations, especially free energy along the path, to various parameters in the computation. Alchemical free energy simulations with a specific thermodynamic cycle are used to probe the effect of including the first solvation shell into the QM region when computing solvation free energies. For cases where high-level QM/MM potential functions are needed, we analyze two different approaches: the QM/MM-MFEP method of Yang and co-workers and perturbative correction to low-level QM/MM free energy results. For the examples analyzed here, both approaches seem productive although care needs to be exercised when analyzing the perturbative corrections. PMID:27563170

Exploring the evolution of color-luminosity parameter β and its effects on parameter estimation

NASA Astrophysics Data System (ADS)

Wang, Shuang; Li, Yun-He; Zhang, Xin

2014-03-01

It has been found in previous studies that, for the Supernova Legacy Survey three-year (SNLS3) data, there is strong evidence for the redshift evolution of color-luminosity parameter β. In this paper, using the three simplest dark energy models, i.e., the Λ-cold-dark-matter (ΛCDM) model, the wCDM model, and the Chevallier-Polarski-Linder model, we further explore the evolution of β and its effects on parameter estimation. In addition to the SNLS3 data, we also take into account the Planck distance priors data of the cosmic microwave background (CMB), as well as the latest galaxy clustering (GC) data extracted from SDSS DR7 and BOSS. We find that, for all the models, adding a parameter of β can reduce χmin2 by ˜36, indicating that β1=0 is ruled out at 6σ confidence levels. In other words, β deviates from a constant at 6σ confidence levels. This conclusion is insensitive to the dark energy models considered, showing the importance of considering the evolution of β in the cosmology fits. Furthermore, it is found that varying β can significantly change the fitting results of various cosmological parameters: using the SNLS3 data alone, varying β yields a larger Ωm for the ΛCDM model; using the SNLS3+CMB +GC data, varying β yields a larger Ωm and a smaller h for all the models. Moreover, we find that these results are much closer to those given by the CMB +GC data compared to the cases of treating β as a constant. This indicates that considering the evolution of β is very helpful for reducing the tension between supernova and other cosmological observations.

Characterization of cellulosic wastes and gasification products from chicken farms

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

Joseph, Paul, E-mail: p.joseph@ulster.ac.uk; Tretsiakova-McNally, Svetlana; McKenna, Siobhan

Highlights: Black-Right-Pointing-Pointer The gas chromatography indicated the variable quality of the producer gas. Black-Right-Pointing-Pointer The char had appreciable NPK values, and can be used as a fertiliser. Black-Right-Pointing-Pointer The bio-oil produced was of poor quality, having high moisture content and low pH. Black-Right-Pointing-Pointer Mass and energy balances showed inadequate level energy recovery from the process. Black-Right-Pointing-Pointer Future work includes changing the operating parameters of the gasification unit. - Abstract: The current article focuses on gasification as a primary disposal solution for cellulosic wastes derived from chicken farms, and the possibility to recover energy from this process. Wood shavings and chickenmore » litter were characterized with a view to establishing their thermal parameters, compositional natures and calorific values. The main products obtained from the gasification of chicken litter, namely, producer gas, bio-oil and char, were also analysed in order to establish their potential as energy sources. The experimental protocol included bomb calorimetry, pyrolysis combustion flow calorimetry (PCFC), thermo-gravimetric analyses (TGA), differential scanning calorimetry (DSC), Fourier transform infrared (FT-IR) spectroscopy, Raman spectroscopy, elemental analyses, X-ray diffraction (XRD), mineral content analyses and gas chromatography. The mass and energy balances of the gasification unit were also estimated. The results obtained confirmed that gasification is a viable method of chicken litter disposal. In addition to this, it is also possible to recover some energy from the process. However, energy content in the gas-phase was relatively low. This might be due to the low energy efficiency (19.6%) of the gasification unit, which could be improved by changing the operation parameters.« less

Energy absorption capabilities of composite sandwich panels under blast loads

NASA Astrophysics Data System (ADS)

Sankar Ray, Tirtha

As blast threats on military and civilian structures continue to be a significant concern, there remains a need for improved design strategies to increase blast resistance capabilities. The approach to blast resistance proposed here is focused on dissipating the high levels of pressure induced during a blast through maximizing the potential for energy absorption of composite sandwich panels, which are a competitive structural member type due to the inherent energy absorption capabilities of fiber reinforced polymer (FRP) composites. Furthermore, the middle core in the sandwich panels can be designed as a sacrificial layer allowing for a significant amount of deformation or progressive failure to maximize the potential for energy absorption. The research here is aimed at the optimization of composite sandwich panels for blast mitigation via energy absorption mechanisms. The energy absorption mechanisms considered include absorbed strain energy due to inelastic deformation as well as energy dissipation through progressive failure of the core of the sandwich panels. The methods employed in the research consist of a combination of experimentally-validated finite element analysis (FEA) and the derivation and use of a simplified analytical model. The key components of the scope of work then includes: establishment of quantified energy absorption criteria, validation of the selected FE modeling techniques, development of the simplified analytical model, investigation of influential core architectures and geometric parameters, and investigation of influential material properties. For the parameters that are identified as being most-influential, recommended values for these parameters are suggested in conceptual terms that are conducive to designing composite sandwich panels for various blast threats. Based on reviewing the energy response characteristic of the panel under blast loading, a non-dimensional parameter AET/ ET (absorbed energy, AET, normalized by total energy, ET) was suggested to compare energy absorption capabilities of the structures under blast loading. In addition, AEweb/ET (where AEweb is the energy absorbed by the middle core) was also employed to evaluate the energy absorption contribution from the web. Taking advantage of FEA and the simplified analytical model, the influences of material properties as well as core architectures and geometries on energy absorption capabilities (quantified by AET/ ET and AEweb/E T) were investigated through parametric studies. Results from the material property investigation indicated that density of the front face sheet and strength were most influential on the energy absorption capability of the composite sandwich panels under blast loading. The study to investigate the potential effectiveness of energy absorbed via inelastic deformation compared to energy absorbed via progressive failure indicated that for practical applications (where the position of bomb is usually unknown and the panel is designed to be the same anywhere), the energy absorption via inelastic deformation is the more efficient approach. Regarding the geometric optimization, it was found that a core architecture consisting of vertically-oriented webs was ideal. The optimum values for these parameters can be generally described as those which cause the most inelasticity, but not failure, of the face sheets and webs.

Properties of {sup 112}Cd from the (n,n'{gamma}) reaction: Levels and level densities

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

Garrett, P. E.; Lehmann, H.; Jolie, J.

2001-08-01

Levels in {sup 112}Cd have been studied through the (n,n'{gamma}) reaction with monoenergetic neutrons. An extended set of experiments that included excitation functions, {gamma}-ray angular distributions, and {gamma}{gamma} coincidence measurements was performed. A total of 375 {gamma} rays were placed in a level scheme comprising 200 levels (of which 238 {gamma}-ray assignments and 58 levels are newly established) up to 4 MeV in excitation. No evidence to support the existence of 47 levels as suggested in previous studies was found, and these have been removed from the level scheme. From the results, a comparison of the level density is mademore » with the constant temperature and back-shifted Fermi gas models. The back-shifted Fermi gas model with the Gilbert-Cameron spin cutoff parameter provided the best overall fit. Without using the neutron resonance information and only fitting the cumulative number of low-lying levels, the level density parameters extracted are a sensitive function of the maximum energy used in the fit.« less

Molecular spectroscopy and collisional excitation. [in astrophysics

NASA Technical Reports Server (NTRS)

Green, S.

1975-01-01

The paper examines the basic principles underlying the molecular transitions responsible for interstellar molecular spectra. The energy levels of molecules are discussed in detail with special attention given to the Born-Oppenheimer approximation, the electronic Hamiltonian, and the parameters of vibrational and rotational energy. The probabilities for radiative and collisional transitions are calculated. A brief review of techniques for molecular spectroscopy is presented along with methods used to determine collision cross sections on both an experimental and a theoretical basis.

Ab initio theory of the N2V defect in diamond for quantum memory implementation

NASA Astrophysics Data System (ADS)

Udvarhelyi, Péter; Thiering, Gergő; Londero, Elisa; Gali, Adam

2017-10-01

The N2V defect in diamond is characterized by means of ab initio methods relying on density functional theory calculated parameters of a Hubbard model Hamiltonian. It is shown that this approach appropriately describes the energy levels of correlated excited states induced by this defect. By determining its critical magneto-optical parameters, we propose to realize a long-living quantum memory by N2V defect, i.e., H 3 color center in diamond.

Total energy intake according to the level of skeletal muscle mass in Korean adults aged 30 years and older: an analysis of the Korean National Health and Nutrition Examination Surveys (KNHANES) 2008-2011.

PubMed

Jang, Bo Young; Bu, So Young

2018-06-01

Since gain or loss of skeletal muscle mass is a gradual event and occurs due to a combination of lifestyle factors, assessment of dietary factors related to skeletal muscle is complicated. The aim of this study was to investigate the changes in total energy intake according to the level of skeletal muscle mass. A total of 8,165 subjects ≥ 30 years of age from the Korean National Health and Nutrition Examination Surveys (KNHANES) 2008-2011 were included in the analysis, and multivariate-adjusted regression analyses were performed to analyze the association of the quartiles of sarcopenia index (SI) with energy intake of the study population after adjusting for age and metabolic parameters. The increase in SI quartile was in proportion to the gradual decrease in systemic lipids and the anthropometric measurement of fat accumulation ( P < 0.001). Subjects in higher SI quartiles tended to consume more total energy and energy-producing nutrients than those in lower quartiles ( P < 0.001). After age, body weight, alcohol consumption, and metabolic parameters were adjusted in the analysis, total energy intake gradually increased according to the increase in SI quartile, and the association between total energy intake and SI was more pronounced in men. However, the risk (odd ratio) of having a low SI was not affected by any single macronutrient intake. In this study, total energy intake was positively associated with SI and relative skeletal mass in both men and women. However, no significant association or a weak association was observed between any single macronutrient intake and skeletal muscle mass. The data indicated that acquiring more energy intake within the normal range of energy consumption may help to maintain skeletal muscle mass.

Experimental differential cross sections, level densities, and spin cutoffs as a testing ground for nuclear reaction codes

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

Voinov, Alexander V.; Grimes, Steven M.; Brune, Carl R.

Proton double-differential cross sections from 59Co(α,p) 62Ni, 57Fe(α,p) 60Co, 56Fe( 7Li,p) 62Ni, and 55Mn( 6Li,p) 60Co reactions have been measured with 21-MeV α and 15-MeV lithium beams. Cross sections have been compared against calculations with the empire reaction code. Different input level density models have been tested. It was found that the Gilbert and Cameron [A. Gilbert and A. G. W. Cameron, Can. J. Phys. 43, 1446 (1965)] level density model is best to reproduce experimental data. Level densities and spin cutoff parameters for 62Ni and 60Co above the excitation energy range of discrete levels (in continuum) have been obtainedmore » with a Monte Carlo technique. Furthermore, excitation energy dependencies were found to be inconsistent with the Fermi-gas model.« less

Optical model with multiple band couplings using soft rotator structure

NASA Astrophysics Data System (ADS)

Martyanov, Dmitry; Soukhovitskii, Efrem; Capote, Roberto; Quesada, Jose Manuel; Chiba, Satoshi

2017-09-01

A new dispersive coupled-channel optical model (DCCOM) is derived that describes nucleon scattering on 238U and 232Th targets using a soft-rotator-model (SRM) description of the collective levels of the target nucleus. SRM Hamiltonian parameters are adjusted to the observed collective levels of the target nucleus. SRM nuclear wave functions (mixed in K quantum number) have been used to calculate coupling matrix elements of the generalized optical model. Five rotational bands are coupled: the ground-state band, β-, γ-, non-axial- bands, and a negative parity band. Such coupling scheme includes almost all levels below 1.2 MeV of excitation energy of targets. The "effective" deformations that define inter-band couplings are derived from SRM Hamiltonian parameters. Conservation of nuclear volume is enforced by introducing a monopolar deformed potential leading to additional couplings between rotational bands. The present DCCOM describes the total cross section differences between 238U and 232Th targets within experimental uncertainty from 50 keV up to 200 MeV of neutron incident energy. SRM couplings and volume conservation allow a precise calculation of the compound-nucleus (CN) formation cross sections, which is significantly different from the one calculated with rigid-rotor potentials with any number of coupled levels.

Effect of anapanasati meditation technique through electrophotonic imaging parameters: A pilot study

PubMed Central

Deo, Guru; Itagi R, Kumar; Thaiyar M, Srinivasan; Kuldeep, Kushwah K

2015-01-01

Background: Mindfulness along with breathing is a well-established meditation technique. Breathing is an exquisite tool for exploring subtle awareness of mind and life itself. Aim: This study aimed at measuring changes in the different parameters of electrophotonic imaging (EPI) in anapanasati meditators. Materials and Methods: To carry out this study, 51 subjects comprising 32 males and 19 females of age 18 years and above (mean age 45.64 ± 14.43) were recruited voluntarily with informed consent attending Karnataka Dhyana Mahachakra-1 at Pyramid Valley International, Bengaluru, India. The design was a single group pre- post and data collected by EPI device before and after 5 days of intensive meditation. Results: Results show significant changes in EPI parameter integral area with filter (physiological) in both right and left side, which reflects the availability of high functional energy reserve in meditators. The researchers observed similar trends without filter (psycho-physiological) indicating high reserves of energy at psycho-physiological level also. Activation coefficient, another parameter of EPI, reduced showing more relaxed state than earlier, possibly due to parasympathetic dominance. Integral entropy decreased in the case of psycho-physiological parameters left-side without filter, which indicates less disorder after meditation, but these changes were not significant. The study showed a reversed change in integral entropy in the right side without filter; however, the values on both sides with filter increased, which indicates disorder. Conclusion: The study suggests that EPI can be used in the recording functional physiological and psychophysiological status of meditators at a subtle level. PMID:26170590

DEPOT: A Database of Environmental Parameters, Organizations and Tools

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

CARSON,SUSAN D.; HUNTER,REGINA LEE; MALCZYNSKI,LEONARD A.

2000-12-19

The Database of Environmental Parameters, Organizations, and Tools (DEPOT) has been developed by the Department of Energy (DOE) as a central warehouse for access to data essential for environmental risk assessment analyses. Initial efforts have concentrated on groundwater and vadose zone transport data and bioaccumulation factors. DEPOT seeks to provide a source of referenced data that, wherever possible, includes the level of uncertainty associated with these parameters. Based on the amount of data available for a particular parameter, uncertainty is expressed as a standard deviation or a distribution function. DEPOT also provides DOE site-specific performance assessment data, pathway-specific transport data,more » and links to environmental regulations, disposal site waste acceptance criteria, other environmental parameter databases, and environmental risk assessment models.« less

Hydrogen bonding in ionic liquids.

PubMed

Hunt, Patricia A; Ashworth, Claire R; Matthews, Richard P

2015-03-07

Ionic liquids (IL) and hydrogen bonding (H-bonding) are two diverse fields for which there is a developing recognition of significant overlap. Doubly ionic H-bonds occur when a H-bond forms between a cation and anion, and are a key feature of ILs. Doubly ionic H-bonds represent a wide area of H-bonding which has yet to be fully recognised, characterised or explored. H-bonds in ILs (both protic and aprotic) are bifurcated and chelating, and unlike many molecular liquids a significant variety of distinct H-bonds are formed between different types and numbers of donor and acceptor sites within a given IL. Traditional more neutral H-bonds can also be formed in functionalised ILs, adding a further level of complexity. Ab initio computed parameters; association energies, partial charges, density descriptors as encompassed by the QTAIM methodology (ρBCP), qualitative molecular orbital theory and NBO analysis provide established and robust mechanisms for understanding and interpreting traditional neutral and ionic H-bonds. In this review the applicability and extension of these parameters to describe and quantify the doubly ionic H-bond has been explored. Estimating the H-bonding energy is difficult because at a fundamental level the H-bond and ionic interaction are coupled. The NBO and QTAIM methodologies, unlike the total energy, are local descriptors and therefore can be used to directly compare neutral, ionic and doubly ionic H-bonds. The charged nature of the ions influences the ionic characteristics of the H-bond and vice versa, in addition the close association of the ions leads to enhanced orbital overlap and covalent contributions. The charge on the ions raises the energy of the Ylp and lowers the energy of the X-H σ* NBOs resulting in greater charge transfer, strengthening the H-bond. Using this range of parameters and comparing doubly ionic H-bonds to more traditional neutral and ionic H-bonds it is clear that doubly ionic H-bonds cover the full range of weak through to very strong H-bonds.

2n-emission from 205Pb* nucleus using clusterization approach at Ebeam˜14-20 MeV

NASA Astrophysics Data System (ADS)

Kaur, Amandeep; Sandhu, Kiran; Sharma, Manoj Kumar

2016-05-01

The dynamics involved in n-induced reaction with 204Pb target is analyzed and the decay of the composite system 205Pb* is governed within the collective clusterization approach of the Dynamical Cluster-decay Model (DCM). The experimental data for 2n-evaporation channel is available for neutron energy range of 14-20 MeV and is addressed by optimizing the only parameter of the model, the neck-length parameter (ΔR). The calculations are done by taking the quadrupole (β2) deformations of the decaying fragments and the calculated 2n-emission cross-sections find nice agreement with available data. An effort is made to study the role of level density parameter in the decay of hot-rotating nucleus, and the mass dependence in level density parameter is exercised for the first time in DCM based calculations. It is to be noted that the effect of deformation, temperature and angular momentum etc. is studied to extract better description of the dynamics involved.

The behavior of gain and saturation characteristics versus temperature in a copper bromide laser

NASA Astrophysics Data System (ADS)

Mohammadpour Lima, S.; Behrouzinia, S.; Salem, M. K.; Elahei, M.; Khorasani, K.; Dorranian, D.

2017-05-01

A pair of copper bromide lasers in an oscillator-amplifier configuration was used to investigate the temperature dependence of the small-signal gain, saturation intensity, and output power of the laser. The observations were explained in terms of the electron temperature and energy levels of transition. An optimum electrical input power of 1.6 kW and a corresponding operational temperature of 510 °C were determined for the maximum values of these parameters. The balance between the microscopic parameters, such as stimulated emission cross-section, laser upper-level lifetime, and population inversion, which determine the behavior of the amplifying parameters and laser output power with respect to the operational temperature, has been investigated. We used the steady-state rate equation from the Hargrove model to determine the amplifying parameters, instead of the Frantz-Nodvik formula. The power extracted from the amplifier exceeds that achieved with the same device as the oscillator by more than 60%.

Sound quality characteristics of refrigerator noise in real living environments with relation to psychoacoustical and autocorrelation function parameters.

PubMed

Sato, Shin-ichi; You, Jin; Jeon, Jin Yong

2007-07-01

Psychoacoustical and autocorrelation function (ACF) parameters were employed to describe the temporal fluctuations of refrigerator noise during starting, transition into/from the stationary phase and termination of operation. The temporal fluctuations of refrigerator noise include a click at start-up, followed by a rapid increase in volume, a change of pitch, and termination of the operation. Subjective evaluations of the noise of 24 different refrigerators were conducted in a real living environment. The relationship between objective measures and perceived noisiness was examined by multiple regression analysis. Sound quality indices were developed based on psychoacoustical and ACF parameters. The psychoacoustical parameters found to be important for evaluating noisiness in the stationary phase were loudness and roughness. The relationship between noisiness and ACF parameters shows that sound energy and its fluctuations are important for evaluating noisiness. Also, refrigerator sounds that had a fluctuation of pitch were rated as more annoying. The tolerance level for the starting phase of refrigerator noise was found to be 33 dBA, which is the level where 65% of the participants in the subjective tests were satisfied.

Observational tests of non-adiabatic Chaplygin gas

NASA Astrophysics Data System (ADS)

Carneiro, S.; Pigozzo, C.

2014-10-01

In a previous paper [1] it was shown that any dark sector model can be mapped into a non-adiabatic fluid formed by two interacting components, one with zero pressure and the other with equation-of-state parameter ω = -1. It was also shown that the latter does not cluster and, hence, the former is identified as the observed clustering matter. This guarantees that the dark matter power spectrum does not suffer from oscillations or instabilities. It applies in particular to the generalised Chaplygin gas, which was shown to be equivalent to interacting models at both background and perturbation levels. In the present paper we test the non-adiabatic Chaplygin gas against the Hubble diagram of type Ia supernovae, the position of the first acoustic peak in the anisotropy spectrum of the cosmic microwave background and the linear power spectrum of large scale structures. We consider two different compilations of SNe Ia, namely the Constitution and SDSS samples, both calibrated with the MLCS2k2 fitter, and for the power spectrum we use the 2dFGRS catalogue. The model parameters to be adjusted are the present Hubble parameter, the present matter density and the Chaplygin gas parameter α. The joint analysis best fit gives α ≈ - 0.5, which corresponds to a constant-rate energy flux from dark energy to dark matter, with the dark energy density decaying linearly with the Hubble parameter. The ΛCDM model, equivalent to α = 0, stands outside the 3σ confidence interval.

[The effect of exogenous iron on levels of adenosinetriphosphate and 2,3-diphosphoglycerate in erythrocytes of men during extreme physical exertion].

PubMed

Pedzikiewicz, J; Sobiech, K A

1995-01-01

Nine men were examined during a three-week training requiring much physical effort. They were given nutrient, "LIVEX", enriched with iron. Hematological parameters as well as concentration of erythrocyte ATP and 2,3-DPG were determined before and after the experiment. Hematological parameters were determined using standard methods while Boehringer's test (Germany) was used for determining ATP and 2,3-DPG. The level of reticular cells was statistically higher after the experiment, and the increase in ATP and 2,3-DPG concentration was insignificant. A positive adaptation of energy metabolism after exogenous iron administration during physical effort was discussed.

Optimization under Uncertainty of a Biomass-integrated Renewable Energy Microgrid with Energy Storage

NASA Astrophysics Data System (ADS)

Zheng, Yingying

The growing energy demands and needs for reducing carbon emissions call more and more attention to the development of renewable energy technologies and management strategies. Microgrids have been developed around the world as a means to address the high penetration level of renewable generation and reduce greenhouse gas emissions while attempting to address supply-demand balancing at a more local level. This dissertation presents a model developed to optimize the design of a biomass-integrated renewable energy microgrid employing combined heat and power with energy storage. A receding horizon optimization with Monte Carlo simulation were used to evaluate optimal microgrid design and dispatch under uncertainties in the renewable energy and utility grid energy supplies, the energy demands, and the economic assumptions so as to generate a probability density function for the cost of energy. Case studies were examined for a conceptual utility grid-connected microgrid application in Davis, California. The results provide the most cost effective design based on the assumed energy load profile, local climate data, utility tariff structure, and technical and financial performance of the various components of the microgrid. Sensitivity and uncertainty analyses are carried out to illuminate the key parameters that influence the energy costs. The model application provides a means to determine major risk factors associated with alternative design integration and operating strategies.

Impact of seasonal thermal stress on physiological and blood biochemical parameters in pigs under different dietary energy levels.

PubMed

Pathak, P K; Roychoudhury, R; Saharia, J; Borah, M C; Dutta, D J; Bhuyan, R; Kalita, D

2018-06-01

The present study was formulated to find out the status of important season related thermal stress biomarkers of pure-bred (Hampshire) and crossbred (50% Hampshire × 50% local) pigs under the agro-climatic condition of Assam State, India. The experiment was also aimed to study the role of different level of energy ration (110, 100, and 90% energy of NRC feeding standard for pig) in variation of physiological and biochemical parameters in two genetic groups of pigs in different seasons. The metabolizable energy value were 3260, 2936.5, and 3585.8 kcal/kg in grower ration and 3260.2, 2936.6, and 3587 kcal/kg in finisher ration for normal energy (NE), low energy (LE) and high energy (HE), respectively. Both the genetic group of animals were housed separately under intensive system of management. Each pen was measuring 10' × 12' along with an outer enclosure. Six weaned piglets (almost similar body weight of average 10.55 kg) of each group were kept in a separate pen. However, after attainment of 35 kg body weight, the animals of a group were divided in two pens of three animals each. The present experiment indicated that average ambient temperature during summer months (27.33-29.51 °C) was above the comfort zone for pigs (22 °C). The significantly (P < 0.01) higher relative humidity (RH) (%) was recorded in outdoor environment (87.26-91.10%) and in the morning time (86.60-91.10%). The temperature humidity index (THI) during the study period was found to be indicative of thermal stress to the experimental animals during summer (79.55-82.56). Physiological parameters viz., respiration rate (RR) and rectal temperature (RT) were significantly (P < 0.01) higher in summer season (43.75-72.12 breaths/min. and 102.29-103.23 °F) and non-significantly higher values were recorded in Hampshire pigs. It was also found that the significantly (P < 0.01) lower RR as well as RT was recorded in the pigs fed with high energy (HE) ration during summer season. Serum triiodothyronine (T 3 ) and thyroxine (T 4 ) concentrations were significantly (P < 0.01) lower during summer, while both the genetic groups showed significantly (P < 0.01) higher concentration of serum cortisol during summer season. It was also observed that thyroid hormone and cortisol concentrations were maintained in groups of pig fed vegetable oil incorporated HE diet during summer. From the present study, it is found that the increasing the energy level of the ration might be helpful to minimize the effects of thermal stress during summer.

Probing the energy levels of perovskite solar cells via Kelvin probe and UV ambient pressure photoemission spectroscopy.

PubMed

Harwell, J R; Baikie, T K; Baikie, I D; Payne, J L; Ni, C; Irvine, J T S; Turnbull, G A; Samuel, I D W

2016-07-20

The field of organo-lead halide perovskite solar cells has been rapidly growing since their discovery in 2009. State of the art devices are now achieving efficiencies comparable to much older technologies like silicon, while utilising simple manufacturing processes and starting materials. A key parameter to consider when optimising solar cell devices or when designing new materials is the position and effects of the energy levels in the materials. We present here a comprehensive study of the energy levels present in a common structure of perovskite solar cell using an advanced macroscopic Kelvin probe and UV air photoemission setup. By constructing a detailed map of the energy levels in the system we are able to predict the importance of each layer to the open circuit voltage of the solar cell, which we then back up through measurements of the surface photovoltage of the cell under white illumination. Our results demonstrate the effectiveness of air photoemission and Kelvin probe contact potential difference measurements as a method of identifying the factors contributing to the open circuit voltage in a solar cell, as well as being an excellent way of probing the physics of new materials.

Determination of Optimum Operation Parameters for Low-Intensity Pulsed Ultrasound and Low-Level Laser Based Treatment to Induce Proliferation of Osteoblast and Fibroblast Cells.

PubMed

Coskun, Mehmet Emre; Coskun, Kubra Acikalin; Tutar, Yusuf

2018-05-01

The aim of this study was to determine the optimum operating parameters (pulse duration, energy levels, and application time) to promote induction of osteoblast and fibroblast cell proliferation and to maintain cell viability treated with low-intensity pulsed ultrasound (LIPUS) and low-level laser therapy (LLLT). The positive effects of LIPUS and LLLT on cellular activity have been reported in recent years. Comparisons between experimental parameters of previous studies are difficult because scientific studies reported frequencies and the duty cycles of LIPUS and wavelengths and doses of LLLT in a wide range of parameters. However, optimum amount of energy and optimum time exposure must be determined to induce bone and tissue cell proliferation for effective healing process and to avoid cell damage. Fibroblast and osteoblast cell cultures were irradiated with LIPUS (10-50% pulse and continuous mode at 1 and 3 MHz for 1, 3, and 5 min) and LLLT (4, 8, and 16 J at 50, 100, 200, 300, 400, and 500 mW). Cell cultures were analyzed using XTT assay. For both cell types, LIPUS treatment with 10% pulse (1:9 duty cycle), 3 MHz, and for 1 min and LLLT treatment over 100 mV for 4, 8, and 16 J modalities contributed to the growth, and may help bone repair and tissue healing process optimally. Bio-stimulating effects of LLLT irradiation promote proliferation and maintain cell viability better than LIPUS treatment without causing thermal response for both cell types, and the therapeutic modality above 200 mV has maximum effectiveness.

Computational analysis of an autophagy/translation switch based on mutual inhibition of MTORC1 and ULK1

DOE PAGES

Szymańska, Paulina; Martin, Katie R.; MacKeigan, Jeffrey P.; ...

2015-03-11

We constructed a mechanistic, computational model for regulation of (macro)autophagy and protein synthesis (at the level of translation). The model was formulated to study the system-level consequences of interactions among the following proteins: two key components of MTOR complex 1 (MTORC1), namely the protein kinase MTOR (mechanistic target of rapamycin) and the scaffold protein RPTOR; the autophagy-initiating protein kinase ULK1; and the multimeric energy-sensing AMP-activated protein kinase (AMPK). Inputs of the model include intrinsic AMPK kinase activity, which is taken as an adjustable surrogate parameter for cellular energy level or AMP:ATP ratio, and rapamycin dose, which controls MTORC1 activity. Outputsmore » of the model include the phosphorylation level of the translational repressor EIF4EBP1, a substrate of MTORC1, and the phosphorylation level of AMBRA1 (activating molecule in BECN1-regulated autophagy), a substrate of ULK1 critical for autophagosome formation. The model incorporates reciprocal regulation of mTORC1 and ULK1 by AMPK, mutual inhibition of MTORC1 and ULK1, and ULK1-mediated negative feedback regulation of AMPK. Through analysis of the model, we find that these processes may be responsible, depending on conditions, for graded responses to stress inputs, for bistable switching between autophagy and protein synthesis, or relaxation oscillations, comprising alternating periods of autophagy and protein synthesis. A sensitivity analysis indicates that the prediction of oscillatory behavior is robust to changes of the parameter values of the model. The model provides testable predictions about the behavior of the AMPK-MTORC1-ULK1 network, which plays a central role in maintaining cellular energy and nutrient homeostasis.« less

Constraints on the unified dark energy dark matter model from latest observational data

NASA Astrophysics Data System (ADS)

Wu, Puxun; Yu, Hongwei

2007-03-01

The generalized Chaplygin gas (GCG) is studied in this paper by using the latest observational data including 182 gold sample type Ia supernovae (Sne Ia) data, the ESSENCE Sne Ia data, the distance ratio from z = 0.35 to 1089 (the redshift of decoupling), the cosmic microwave background shift parameter and the Hubble parameter data. Our results rule out the standard Chaplygin gas model (α = 1) at the 99.7% confidence level, but allow for the λCDM model (α = 0) at the 68.3% confidence level. At a 95.4% confidence level, we obtain w = -0.74-0.09+0.10 and α = -0.14-0.19+0.30. In addition, we find that the phase transition from deceleration to acceleration occurs at redshift zq = 0~0.78-0.89 at a 1σ confidence level for the GCG model.

Renewable Orphans: Adopting Legal Renewable Standards at the State Level

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

Ferrey, Steven

To keep making progress on renewable energy deployment, state incentives must be structured to comply with constitutional requirements. While states can experiment, and indeed have taken the lead on renewable policy initiatives, the programs must be carefully sculpted within the legal parameters of the dormant Commerce Clause. (author)

Propensity and Risk Assessment for Solar Particle Events: Consideration of Integral Fluence at High Proton Energies

NASA Technical Reports Server (NTRS)

Kim, Myung-Hee; Hayat, Matthew J.; Feiveson, alan H.; Cucinotta, Francis A.

2008-01-01

For future space missions with longer duration, exposure to large solar particle events (SPEs) with high energy levels is the major concern during extra-vehicular activities (EVAs) on the lunar and Mars surface. The expected SPE propensity for large proton fluence was estimated from a non-homogeneous Poisson model using the historical database for measurements of protons with energy > 30 MeV, Phi(sub 30). The database includes a continuous data set for the past 5 solar cycles. The resultant SPE risk analysis for a specific mission period was made including the 95% confidence level. In addition to total particle intensity of SPE, the detailed energy spectra of protons especially at high energy levels were recognized as extremely important parameter for the risk assessment, since there remains a significant cancer risks from those energetic particles for large events. Using all the recorded proton fluence of SPEs for energies >60 and >100 MeV, Phi(sub 60) and Phi(sub 100), respectively, the expected propensities of SPEs abundant with high energy protons were estimated from the same non-homogeneous Poisson model and the representative cancer risk was analyzed. The dependencies of risk with different energy spectra, for e.g. between soft and hard SPEs, were evaluated. Finally, we describe approaches to improve radiation protection of astronauts and optimize mission planning for future space missions.

Ghrelin and leptin modulate the feeding behaviour of the hawksbill turtle Eretmochelys imbricata during nesting season

PubMed Central

Goldberg, Daphne Wrobel; Leitão, Santiago Alonso Tobar; Godfrey, Matthew H.; Lopez, Gustave Gilles; Santos, Armando José Barsante; Neves, Fabiana Alves; de Souza, Érica Patrícia Garcia; Moura, Anibal Sanchez; Bastos, Jayme da Cunha; Bastos, Vera Lúcia Freire da Cunha

2013-01-01

Female sea turtles have rarely been observed foraging during the nesting season. This suggests that prior to their migration to nesting beaches the females must store sufficient energy and nutrients at their foraging grounds and must be physiologically capable of undergoing months without feeding. Leptin (an appetite-suppressing protein) and ghrelin (a hunger-stimulating peptide) affect body weight by influencing energy intake in all vertebrates. We investigated the levels of these hormones and other physiological and nutritional parameters in nesting hawksbill sea turtles in Rio Grande do Norte State, Brazil, by collecting consecutive blood samples from 41 turtles during the 2010–2011 and 2011–2012 reproductive seasons. We found that levels of serum leptin decreased over the nesting season, which potentially relaxed suppression of food intake and stimulated females to begin foraging either during or after the post-nesting migration. Concurrently, we recorded an increasing trend in ghrelin, which may have stimulated food intake towards the end of the nesting season. Both findings are consistent with the prediction that post-nesting females will begin to forage, either during or immediately after their post-nesting migration. We observed no seasonal trend for other physiological parameters (values of packed cell volume and serum levels of alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, γ-glutamyl transferase, low-density lipoprotein, and high-density lipoprotein). The observed downward trends in general serum biochemistry levels were probably due to the physiological challenge of vitellogenesis and nesting in addition to limited energy resources and probable fasting. PMID:27293600

Ghrelin and leptin modulate the feeding behaviour of the hawksbill turtle Eretmochelys imbricata during nesting season.

PubMed

Goldberg, Daphne Wrobel; Leitão, Santiago Alonso Tobar; Godfrey, Matthew H; Lopez, Gustave Gilles; Santos, Armando José Barsante; Neves, Fabiana Alves; de Souza, Érica Patrícia Garcia; Moura, Anibal Sanchez; Bastos, Jayme da Cunha; Bastos, Vera Lúcia Freire da Cunha

2013-01-01

Female sea turtles have rarely been observed foraging during the nesting season. This suggests that prior to their migration to nesting beaches the females must store sufficient energy and nutrients at their foraging grounds and must be physiologically capable of undergoing months without feeding. Leptin (an appetite-suppressing protein) and ghrelin (a hunger-stimulating peptide) affect body weight by influencing energy intake in all vertebrates. We investigated the levels of these hormones and other physiological and nutritional parameters in nesting hawksbill sea turtles in Rio Grande do Norte State, Brazil, by collecting consecutive blood samples from 41 turtles during the 2010-2011 and 2011-2012 reproductive seasons. We found that levels of serum leptin decreased over the nesting season, which potentially relaxed suppression of food intake and stimulated females to begin foraging either during or after the post-nesting migration. Concurrently, we recorded an increasing trend in ghrelin, which may have stimulated food intake towards the end of the nesting season. Both findings are consistent with the prediction that post-nesting females will begin to forage, either during or immediately after their post-nesting migration. We observed no seasonal trend for other physiological parameters (values of packed cell volume and serum levels of alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, γ-glutamyl transferase, low-density lipoprotein, and high-density lipoprotein). The observed downward trends in general serum biochemistry levels were probably due to the physiological challenge of vitellogenesis and nesting in addition to limited energy resources and probable fasting.

Sensitivity analysis of a coupled hydrodynamic-vegetation model using the effectively subsampled quadratures method (ESQM v5.2)

NASA Astrophysics Data System (ADS)

Kalra, Tarandeep S.; Aretxabaleta, Alfredo; Seshadri, Pranay; Ganju, Neil K.; Beudin, Alexis

2017-12-01

Coastal hydrodynamics can be greatly affected by the presence of submerged aquatic vegetation. The effect of vegetation has been incorporated into the Coupled Ocean-Atmosphere-Wave-Sediment Transport (COAWST) modeling system. The vegetation implementation includes the plant-induced three-dimensional drag, in-canopy wave-induced streaming, and the production of turbulent kinetic energy by the presence of vegetation. In this study, we evaluate the sensitivity of the flow and wave dynamics to vegetation parameters using Sobol' indices and a least squares polynomial approach referred to as the Effective Quadratures method. This method reduces the number of simulations needed for evaluating Sobol' indices and provides a robust, practical, and efficient approach for the parameter sensitivity analysis. The evaluation of Sobol' indices shows that kinetic energy, turbulent kinetic energy, and water level changes are affected by plant stem density, height, and, to a lesser degree, diameter. Wave dissipation is mostly dependent on the variation in plant stem density. Performing sensitivity analyses for the vegetation module in COAWST provides guidance to optimize efforts and reduce exploration of parameter space for future observational and modeling work.

Excited-state quantum phase transitions in systems with two degrees of freedom: Level density, level dynamics, thermal properties

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

Stránský, Pavel; Instituto de Ciencias Nucleares, Universidad Nacional Autónoma de México, 04510, México, D.F.; Macek, Michal

2014-06-15

Quantum systems with a finite number of freedom degrees f develop robust singularities in the energy spectrum of excited states as the system’s size increases to infinity. We analyze the general form of these singularities for low f, particularly f=2, clarifying the relation to classical stationary points of the corresponding potential. Signatures in the smoothed energy dependence of the quantum state density and in the flow of energy levels with an arbitrary control parameter are described along with the relevant thermodynamical consequences. The general analysis is illustrated with specific examples of excited-state singularities accompanying the first-order quantum phase transition. --more » Highlights: •ESQPTs found in infinite-size limit of systems with low numbers of freedom degrees f. •ESQPTs related to non-analytical evolutions of classical phase–space properties. •ESQPT signatures analyzed for general f, particularly f=2, extending known case f=1. •ESQPT signatures identified in smoothened density and flow of energy spectrum. •ESQPTs shown to induce a new type of thermodynamic anomalies.« less

Effect of Curvature on the Impact Damage Characteristics and Residual Strength of Composite Plates

NASA Technical Reports Server (NTRS)

Ambur, Damodar R.; Starnes, James H., Jr.

1998-01-01

The results of a study of the response and failure characteristics of thin, cylindrically curved, composite plates subjected to low-speed impact damage are presented. The results indicate that the plate radius and the plate thickness are important structural parameters that influence the nonlinear response of a plate for a given amount of impact energy. Analytical and experimental contact-force results are compared for several plates and the results correlate well. The impact-energy levels required to cause damage initiation and barely visible impact damage are a function of the plate radius for a given plate thickness. The impact-energy levels required to initiate impact damage for plates with a certain range of radii are greater than plates with other radii. The contact-force results corresponding to these impact-energy levels follow a similar trend. Residual strength results for plates with barely visible impact damage suggest that the compression-after-impact residual strength is also a function of plate radius. The residual strength of impact-damaged flat plates appears to be lower than the residual strength of the corresponding cylindrically curved plates.

FT-Raman, FT-IR spectra and total energy distribution of 3-pentyl-2,6-diphenylpiperidin-4-one: DFT method.

PubMed

Subashchandrabose, S; Saleem, H; Erdogdu, Y; Rajarajan, G; Thanikachalam, V

2011-11-01

FT-Raman and FT-IR spectra were recorded for 3-pentyl-2,6-diphenylpiperidin-4-one (PDPO) sample in solid state. The equilibrium geometries, harmonic vibrational frequencies, infrared and the Raman scattering intensities were computed using DFT/6-31G(d,p) level. Results obtained at this level of theory were used for a detailed interpretation of the infrared and Raman spectra, based on the total energy distribution (TED) of the normal modes. Molecular parameters such as bond lengths, bond angles and dihedral angles were calculated and compared with X-ray diffraction data. This comparison was good agreement. The intra-molecular charge transfer was calculated by means of natural bond orbital analysis (NBO). Hyperconjugative interaction energy was more during the π-π* transition. Energy gap of the molecule was found using HOMO and LUMO calculation, hence the less band gap, which seems to be more stable. Atomic charges of the carbon, nitrogen and oxygen were calculated using same level of calculation. Copyright © 2011 Elsevier B.V. All rights reserved.

Modeling the eco-physiology of the purple mauve stinger, Pelagia noctiluca using Dynamic Energy Budget theory

NASA Astrophysics Data System (ADS)

Augustine, Starrlight; Rosa, Sara; Kooijman, Sebastiaan A. L. M.; Carlotti, François; Poggiale, Jean-Christophe

2014-11-01

Parameters for the standard Dynamic Energy Budget (DEB) model were estimated for the purple mauve stinger, Pelagia noctiluca, using literature data. Overall, the model predictions are in good agreement with data covering the full life-cycle. The parameter set we obtain suggests that P. noctiluca is well adapted to survive long periods of starvation since the predicted maximum reserve capacity is extremely high. Moreover we predict that the reproductive output of larger individuals is relatively insensitive to changes in food level while wet mass and length are. Furthermore, the parameters imply that even if food were scarce (ingestion levels only 14% of the maximum for a given size) an individual would still mature and be able to reproduce. We present detailed model predictions for embryo development and discuss the developmental energetics of the species such as the fact that the metabolism of ephyrae accelerates for several days after birth. Finally we explore a number of concrete testable model predictions which will help to guide future research. The application of DEB theory to the collected data allowed us to conclude that P. noctiluca combines maximizing allocation to reproduction with rather extreme capabilities to survive starvation. The combination of these properties might explain why P. noctiluca is a rapidly growing concern to fisheries and tourism.

The second– and third– order nonlinear optical properties and electronic transition of a NLO chromophore: A DFT study

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

Altürk, Sümeyye, E-mail: sumeyye-alturk@hotmail.com; Avci, Davut, E-mail: davci@sakarya.edu.tr; Tamer, Ömer, E-mail: omertamer@sakarya.edu.tr

2016-03-25

It is well known that the practical applications of second-order and third-order nonlinear optical (NLO) materials have been reported in modern technology, such as optical data processing, transmission and storage, etc. In this respect, the linear and nonlinear optical parameters (the molecular static polarizability (α), and the first–order static hyperpolarizability (β{sub 0}), the second–order static hyperpolarizability (γ)), UV-vis spectra and HOMO and LUMO energies of 2-(1′-(4’’’-Methoxyphenyl)-5′-(thien-2″-yl)pyrrol-2′-yl)-1,3-benzothiazole were investigated by using the HSEh1PBE/6–311G(d,p) level of density functional theory. The UV–vis spectra were simulated using TD/HSEh1PBE/6– 311G(d,p) level, and the major contributions to the electronic transitions were obtained. The molecular hardness (η)more » and electronegativity (χ) parameters were also obtained by using molecular frontier orbital energies. The NLO parameters of the title compound were calculated, and obtained data were compared with that of para-Nitroaniline (pNA) which is a typical NLO material and the corresponding experimental data. Obtained data of the chromosphere display significant molecular second-and third-nonlinearity.« less

Effect of increasing levels of apparent metabolizable energy on laying hens in barn system.

PubMed

Kang, Hwan Ku; Park, Seong Bok; Jeon, Jin Joo; Kim, Hyun Soo; Park, Ki Tae; Kim, Sang Ho; Hong, Eui Chul; Kim, Chan Ho

2018-04-12

This experiment was to investigate the effect of increasing levels of apparent metabolizable energy (AMEn) on the laying performance, egg quality, blood parameter, blood biochemistry, intestinal morphology, and apparent total tract digestibility (ATTD) of energy and nutrients in diets fed to laying hens. A total of three-hundred twenty 33-week-old Hy-Line Brown laying hens (Gallus domesticus) were evenly assigned to four experimental diets of 2,750, 2,850, 2,950, and 3,050 kcal AMEn/kg in floor with deep litter of rice hulls. There were four replicates of each treatment, each consisting of 20 birds in a pen. AMEn intake was increased (linear, p < 0.05) with inclusion level of AMEn in diets increased. Feed intake and feed conversion ratio were improved (linear, p < 0.01), but hen-day egg production tended to be increased as increasing level of AMEn in diets increased. During the experiment, leukocyte concentration and blood biochemistry (total cholesterol, triglyceride, glucose, total protein, calcium, asparate aminotransferase (AST), and alanine transferase (ALT) were not influenced by increasing level of AMEn in diets. Gross energy and ether extract were increased (linear, p < 0.01) with inclusion level of AMEn in diets increased. Laying hens fed high AMEn diet (i.e., 3,050 kcal/kg in the current experiment) tended to overconsume energy with a positive effect on feed intake, feed conversion ratio, nutrient digestibility, and intestinal morphology but not in egg production and egg mass.

Fission dynamics with microscopic level densities

NASA Astrophysics Data System (ADS)

Randrup, Jørgen; Ward, Daniel; Carlsson, Gillis; Døssing, Thomas; Möller, Peter; Åberg, Sven

2018-03-01

Working within the Langevin framework of nuclear shape dynamics, we study the dependence of the evolution on the degree of excitation. As the excitation energy of the fissioning system is increased, the pairing correlations and the shell effects diminish and the effective potential-energy surface becomes ever more liquid-drop like. This feature can be included in the treatment in a formally well-founded manner by using the local level densities as a basis for the shape evolution. This is particularly easy to understand and implement in the Metropolis treatment where the evolution is simulated by means of a random walk on the five-dimensional lattice of shapes for which the potential energy has been tabulated. Because the individual steps between two neighboring lattice sites are decided on the basis of the ratio of the statistical weights, what is needed is the ratio of the local level densities for those shapes, evaluated at the associated local excitation energies. For this purpose, we adapt a recently developed combinatorial method for calculating level densities which employs the same single-particle levels as those that were used for the calculation of the pairing and shell contributions to the macroscopic-microscopic deformation-energy surface. For each nucleus under consideration, the level density (for a fixed total angular momentum) is calculated microscopically for each of the over five million shapes given in the three-quadratic-surface parametrization. This novel treatment, which introduces no new parameters, is illustrated for the fission fragment mass distributions for selected uranium and plutonium cases.

[Energy reactions in the skeletal muscles of rats after a flight on the Kosmos-1129 biosatellite].

PubMed

Mailian, E S; Buravkova, L B; Kokoreva, L V

1983-01-01

The polarographic analysis of biological oxidation in rat skeletal muscles after the 18.5-day flight revealed changes specific for the flight animals: oxidative phosphorylation uncoupling, distinct inertness of energy accumulation 10 hrs after recovery. Tissue respiration inhibition occurred in both flight and synchronous rats suggesting the effect of other than weightlessness factors. In the flight animals the parameters of energy metabolism returned to the prelaunch level within a longer (29 days) time than in the synchronous rats (6 days). Muscles of different function (predominance of fast or slow fibers) showed similar responses of energy metabolism to weightlessness, i. e. inhibition of the intensity and decrease of the energy efficiency of oxidative processes.

Battery management system with distributed wireless sensors

DOEpatents

Farmer, Joseph C.; Bandhauer, Todd M.

2016-02-23

A system for monitoring parameters of an energy storage system having a multiplicity of individual energy storage cells. A radio frequency identification and sensor unit is connected to each of the individual energy storage cells. The radio frequency identification and sensor unit operates to sense the parameter of each individual energy storage cell and provides radio frequency transmission of the parameters of each individual energy storage cell. A management system monitors the radio frequency transmissions from the radio frequency identification and sensor units for monitoring the parameters of the energy storage system.

Enhanced von Weizsäcker Wang-Govind-Carter kinetic energy density functional for semiconductors

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

Shin, Ilgyou; Carter, Emily A., E-mail: eac@princeton.edu

2014-05-14

We propose a new form of orbital-free (OF) kinetic energy density functional (KEDF) for semiconductors that is based on the Wang-Govind-Carter (WGC99) nonlocal KEDF. We enhance within the latter the semi-local von Weizsäcker KEDF term, which is exact for a single orbital. The enhancement factor we introduce is related to the extent to which the electron density is localized. The accuracy of the new KEDF is benchmarked against Kohn-Sham density functional theory (KSDFT) by comparing predicted energy differences between phases, equilibrium volumes, and bulk moduli for various semiconductors, along with metal-insulator phase transition pressures. We also compare point defect andmore » (100) surface energies in silicon for a broad test of its applicability. This new KEDF accurately reproduces the exact non-interacting kinetic energy of KSDFT with only one additional adjustable parameter beyond the three parameters in the WGC99 KEDF; it exhibits good transferability between semiconducting to metallic silicon phases and between various III-V semiconductors without parameter adjustment. Overall, this KEDF is more accurate than previously proposed OF KEDFs (e.g., the Huang-Carter (HC) KEDF) for semiconductors, while the computational efficiency remains at the level of the WGC99 KEDF (several hundred times faster than the HC KEDF). This accurate, fast, and transferable new KEDF holds considerable promise for large-scale OFDFT simulations of metallic through semiconducting materials.« less

Diurnal and long-term variation of instability indices over a tropical region in India

NASA Astrophysics Data System (ADS)

Chakraborty, Rohit; Basha, Ghouse; Venkat Ratnam, M.

2018-07-01

Climatology of atmospheric instability is studied over Gadanki using high-resolution radiosonde launched daily during April 2006 to April 2017. The diurnal and seasonal variation of instability parameters is discussed in relation with surface meteorological parameters. Seasonal variations depict strong variability in instability which is masked by stronger diurnal variation with descending Lifting Condensation Level (LCL) and Level of Free Convection (LFC) between 11 and 18 IST resulting in high Convective Available Potential Energy (CAPE) values and heavy rainfall. On a seasonal basis, parcel parameters are high during the late monsoon and post-monsoon while the instability parameters like Total Totals index (TT) and Vertical Totals index (VT) show highest values in the pre-monsoon associated with strong convection. LFC and LCL start descending with ascent in Equilibrium Level (EL) before the monsoon onset. However after the onset, atmospheric instability falls sharply as supported by decreasing TT, VT and CAPE with increasing LI. The 11-year long-term variation depicts slightly elevated LFC and LCL and declining EL values indicating a decrease in the instability with a decrease in CAPE and K Index (KI) and increase in Lifted Index (LI) and Convective Inhibition (CIN).

Parameter dependence of ELM loss reduction by magnetic perturbations at low pedestal density and collisionality in ASDEX upgrade

NASA Astrophysics Data System (ADS)

Leuthold, N.; Suttrop, W.; Fischer, R.; Kappatou, A.; Kirk, A.; McDermott, R.; Mlynek, A.; Valovič, M.; Willensdorfer, M.; the ASDEX Upgrade Team; the EUROfusion MST1 Team

2017-05-01

ELM mitigation by magnetic perturbations is studied at low pedestal collisionalities down to ITER-like values ({ν }{e,{PED}}* =0.1) in ASDEX Upgrade. A comprehensive database of ELM energy losses for varying plasma density, heating power, edge safety factor and magnetic perturbation structure has been assembled to investigate parameter dependencies of ELM mitigation. It is found that magnetic perturbations with a toroidal mode number n = 2 can reduce the ELM energy loss normalized to the energy stored in the plasma pedestal from about 30% to less than 5%, i.e. by a factor of six, below an electron pedestal collisionality of {ν }{e,{PED}}* =0.4. At this level of ELM mitigation a significant reduction of the pedestal pressure and, therefore, global plasma confinement occurs. This pedestal pressure reduction is mostly due to a reduction of plasma density, the so-called ‘pump-out’ effect. Refueling by neutral beams and in particular by pellet injection is possible and can re-establish confinement, however, the ELM energy loss increases as well with increasing density.

Photovoltaic array: Power conditioner interface characteristics

NASA Technical Reports Server (NTRS)

Gonzalez, C. C.; Hill, G. M.; Ross, R. G., Jr.

1982-01-01

The electrical output (power, current, and voltage) of flat plate solar arrays changes constantly, due primarily to changes in cell temperature and irradiance level. As a result, array loads such as dc-to-ac power conditioners must be capable of accommodating widely varying input levels while maintaining operation at or near the maximum power point of the array. The array operating characteristics and extreme output limits necessary for the systematic design of array load interfaces under a wide variety of climatic conditions are studied. A number of interface parameters are examined, including optimum operating voltage, voltage energy, maximum power and current limits, and maximum open circuit voltage. The effect of array degradation and I-V curve fill factor or the array power conditioner interface is also discussed. Results are presented as normalized ratios of power conditioner parameters to array parameters, making the results universally applicable to a wide variety of system sizes, sites, and operating modes.

Water quality in the Schuylkill River, Pennsylvania: the potential for long-lead forecasts

NASA Astrophysics Data System (ADS)

Block, P. J.; Peralez, J.

2012-12-01

Prior analysis of pathogen levels in the Schuylkill River has led to a categorical daily forecast of water quality (denoted as red, yellow, or green flag days.) The forecast, available to the public online through the Philadelphia Water Department, is predominantly based on the local precipitation forecast. In this study, we explore the feasibility of extending the forecast to the seasonal scale by associating large-scale climate drivers with local precipitation and water quality parameter levels. This advance information is relevant for recreational activities, ecosystem health, and water treatment (energy, chemicals), as the Schuylkill provides 40% of Philadelphia's water supply. Preliminary results indicate skillful prediction of average summertime water quality parameters and characteristics, including chloride, coliform, turbidity, alkalinity, and others, using season-ahead oceanic and atmospheric variables, predominantly from the North Atlantic. Water quality parameter trends, including historic land use changes along the river, association with climatic variables, and prediction models will be presented.

A sequence-dependent rigid-base model of DNA

NASA Astrophysics Data System (ADS)

Gonzalez, O.; Petkevičiutė, D.; Maddocks, J. H.

2013-02-01

A novel hierarchy of coarse-grain, sequence-dependent, rigid-base models of B-form DNA in solution is introduced. The hierarchy depends on both the assumed range of energetic couplings, and the extent of sequence dependence of the model parameters. A significant feature of the models is that they exhibit the phenomenon of frustration: each base cannot simultaneously minimize the energy of all of its interactions. As a consequence, an arbitrary DNA oligomer has an intrinsic or pre-existing stress, with the level of this frustration dependent on the particular sequence of the oligomer. Attention is focussed on the particular model in the hierarchy that has nearest-neighbor interactions and dimer sequence dependence of the model parameters. For a Gaussian version of this model, a complete coarse-grain parameter set is estimated. The parameterized model allows, for an oligomer of arbitrary length and sequence, a simple and explicit construction of an approximation to the configuration-space equilibrium probability density function for the oligomer in solution. The training set leading to the coarse-grain parameter set is itself extracted from a recent and extensive database of a large number of independent, atomic-resolution molecular dynamics (MD) simulations of short DNA oligomers immersed in explicit solvent. The Kullback-Leibler divergence between probability density functions is used to make several quantitative assessments of our nearest-neighbor, dimer-dependent model, which is compared against others in the hierarchy to assess various assumptions pertaining both to the locality of the energetic couplings and to the level of sequence dependence of its parameters. It is also compared directly against all-atom MD simulation to assess its predictive capabilities. The results show that the nearest-neighbor, dimer-dependent model can successfully resolve sequence effects both within and between oligomers. For example, due to the presence of frustration, the model can successfully predict the nonlocal changes in the minimum energy configuration of an oligomer that are consequent upon a local change of sequence at the level of a single point mutation.

A sequence-dependent rigid-base model of DNA.

PubMed

Gonzalez, O; Petkevičiūtė, D; Maddocks, J H

2013-02-07

A novel hierarchy of coarse-grain, sequence-dependent, rigid-base models of B-form DNA in solution is introduced. The hierarchy depends on both the assumed range of energetic couplings, and the extent of sequence dependence of the model parameters. A significant feature of the models is that they exhibit the phenomenon of frustration: each base cannot simultaneously minimize the energy of all of its interactions. As a consequence, an arbitrary DNA oligomer has an intrinsic or pre-existing stress, with the level of this frustration dependent on the particular sequence of the oligomer. Attention is focussed on the particular model in the hierarchy that has nearest-neighbor interactions and dimer sequence dependence of the model parameters. For a Gaussian version of this model, a complete coarse-grain parameter set is estimated. The parameterized model allows, for an oligomer of arbitrary length and sequence, a simple and explicit construction of an approximation to the configuration-space equilibrium probability density function for the oligomer in solution. The training set leading to the coarse-grain parameter set is itself extracted from a recent and extensive database of a large number of independent, atomic-resolution molecular dynamics (MD) simulations of short DNA oligomers immersed in explicit solvent. The Kullback-Leibler divergence between probability density functions is used to make several quantitative assessments of our nearest-neighbor, dimer-dependent model, which is compared against others in the hierarchy to assess various assumptions pertaining both to the locality of the energetic couplings and to the level of sequence dependence of its parameters. It is also compared directly against all-atom MD simulation to assess its predictive capabilities. The results show that the nearest-neighbor, dimer-dependent model can successfully resolve sequence effects both within and between oligomers. For example, due to the presence of frustration, the model can successfully predict the nonlocal changes in the minimum energy configuration of an oligomer that are consequent upon a local change of sequence at the level of a single point mutation.

Effects of energy transfer on quantum efficiency of YAG:Nd

NASA Astrophysics Data System (ADS)

Lupei, V.; Lupei, A.; Georgescu, S.; Yen, W. M.

1989-10-01

Using the energy transfer parameters deduced from the study on nonexponential luminescence decay of the 4F3/2 level of Nd(3+) in YAG at room temperature, it is shown that up to 1.5 at. pct Nd, the relative quantum efficiency is reduced by an amount of 18.2C, C being the relative Nd concentration. It is pointed out that about 20 percent of this reduction is due to a very effective quenching mechanism inside the nearest-neighbor Nd-ion pairs.

Study of Z scaling of runaway electron plateau final loss energy deposition into wall of DIII-D

DOE PAGES

Hollmann, Eric M.; Commaux, Nicolas; Eidietis, Nicholas; ...

2017-06-12

Here, controlled runaway electron (RE) plateau-wall strikes with different initial impurity levels are used to study the effect of background plasma ion charge Z (resistivity) on RE-­wall loss dynamics. It is found that Joule heating (magnetic to kinetic energy conversion) during the final loss does not go up monotonically with increasing Z, but peaks at intermediate Z ~ 6. Joule heating and overall time scales of the RE final loss are found to be reasonably well-described by a basic 0D coupled-circuit model, with only the loss time as a free parameter. This loss time is found to be fairly wellmore » correlated with the avalanche time, possibly suggesting that the RE final loss rate is limited by the avalanche rate. First attempts at measuring total energy deposition to the vessel walls by REs during the final loss are made. At higher plasma impurity levels Z > 5, energy deposition to the wall appears be consistent with modeling, at least within the large uncertainties of the measurement. At low impurity levels Z < 5, however, local energy deposition appears around 5-­20× less than expected, suggesting that the RE energy dissipation at low Z is not fully understood.« less

Study of Z scaling of runaway electron plateau final loss energy deposition into wall of DIII-D

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

Hollmann, Eric M.; Commaux, Nicolas; Eidietis, Nicholas

Here, controlled runaway electron (RE) plateau-wall strikes with different initial impurity levels are used to study the effect of background plasma ion charge Z (resistivity) on RE-­wall loss dynamics. It is found that Joule heating (magnetic to kinetic energy conversion) during the final loss does not go up monotonically with increasing Z, but peaks at intermediate Z ~ 6. Joule heating and overall time scales of the RE final loss are found to be reasonably well-described by a basic 0D coupled-circuit model, with only the loss time as a free parameter. This loss time is found to be fairly wellmore » correlated with the avalanche time, possibly suggesting that the RE final loss rate is limited by the avalanche rate. First attempts at measuring total energy deposition to the vessel walls by REs during the final loss are made. At higher plasma impurity levels Z > 5, energy deposition to the wall appears be consistent with modeling, at least within the large uncertainties of the measurement. At low impurity levels Z < 5, however, local energy deposition appears around 5-­20× less than expected, suggesting that the RE energy dissipation at low Z is not fully understood.« less

Use of Direct Dynamics Simulations to Determine Unimolecular Reaction Paths and Arrhenius Parameters for Large Molecules.

PubMed

Yang, Li; Sun, Rui; Hase, William L

2011-11-08

In a previous study (J. Chem. Phys.2008, 129, 094701) it was shown that for a large molecule, with a total energy much greater than its barrier for decomposition and whose vibrational modes are harmonic oscillators, the expressions for the classical Rice-Ramsperger-Kassel-Marcus (RRKM) (i.e., RRK) and classical transition-state theory (TST) rate constants become equivalent. Using this relationship, a molecule's unimolecular rate constants versus temperature may be determined from chemical dynamics simulations of microcanonical ensembles for the molecule at different total energies. The simulation identifies the molecule's unimolecular pathways and their Arrhenius parameters. In the work presented here, this approach is used to study the thermal decomposition of CH3-NH-CH═CH-CH3, an important constituent in the polymer of cross-linked epoxy resins. Direct dynamics simulations, at the MP2/6-31+G* level of theory, were used to investigate the decomposition of microcanonical ensembles for this molecule. The Arrhenius A and Ea parameters determined from the direct dynamics simulation are in very good agreement with the TST Arrhenius parameters for the MP2/6-31+G* potential energy surface. The simulation method applied here may be particularly useful for large molecules with a multitude of decomposition pathways and whose transition states may be difficult to determine and have structures that are not readily obvious.

a New Phenomenological Formula for Ground-State Binding Energies

NASA Astrophysics Data System (ADS)

Gangopadhyay, G.

A phenomenological formula based on liquid drop model has been proposed for ground-state binding energies of nuclei. The effect due to bunching of single particle levels has been incorporated through a term resembling the one-body Hamiltonian. The effect of n-p interaction has been included through a function of valence nucleons. A total of 50 parameters has been used in the present calculation. The root mean square (r.m.s.) deviation for the binding energy values for 2140 nuclei comes out to be 0.376 MeV, and that for 1091 alpha decay energies is 0.284 MeV. The correspondence with the conventional liquid drop model is discussed.

Energy absorption capability and crashworthiness of composite material structures: A review

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

Carruthers, J.J.; Kettle, A.P.; Robinson, A.M.

1998-10-01

The controlled brittle failure of thermosetting fiber-reinforced polymer composites can provide a very efficient energy absorption mechanism. Consequently, the use of these materials in crashworthy vehicle designs has been the subject of considerable interest. In this respect, their more widespread application has been limited by the complexity of their collapse behavior. This article reviews the current level of understanding i this field, including the correlations between failure mode and energy absorption, the principal material, geometric, and physical parameters relevant to crashworthy design and methods of predicting the energy absorption capability of polymer composites. Areas which require further investigation are identified.more » This review article contains 70 references.« less

Wind Plant Performance Prediction (WP3) Project

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

Craig, Anna

The methods for analysis of operational wind plant data are highly variable across the wind industry, leading to high uncertainties in the validation and bias-correction of preconstruction energy estimation methods. Lack of credibility in the preconstruction energy estimates leads to significant impacts on project financing and therefore the final levelized cost of energy for the plant. In this work, the variation in the evaluation of a wind plant's operational energy production as a result of variations in the processing methods applied to the operational data is examined. Preliminary results indicate that selection of the filters applied to the data andmore » the filter parameters can have significant impacts in the final computed assessment metrics.« less

Review of Concrete Biodeterioration in Relation to Buried Nuclear Waste

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

Turick, C; Berry, C.

Long-term storage of low level radioactive material in below ground concrete disposal units (DUs) (Saltstone Disposal Facility) is a means of depositing wastes generated from nuclear operations of the U.S. Department of Energy. Based on the currently modeled degradation mechanisms, possible microbial induced effects on the structural integrity of buried low level wastes must be addressed. Previous international efforts related to microbial impacts on concrete structures that house low level radioactive waste showed that microbial activity can play a significant role in the process of concrete degradation and ultimately structural deterioration. This literature review examines the recent research in thismore » field and is focused on specific parameters that are applicable to modeling and prediction of the fate of concrete vaults housing stored wastes and the wastes themselves. Rates of concrete biodegradation vary with the environmental conditions, illustrating a need to understand the bioavailability of key compounds involved in microbial activity. Specific parameters require pH and osmotic pressure to be within a certain range to allow for microbial growth as well as the availability and abundance of energy sources like components involved in sulfur, iron and nitrogen oxidation. Carbon flow and availability are also factors to consider in predicting concrete biodegradation. The results of this review suggest that microbial activity in Saltstone, (grouted low level radioactive waste) is unlikely due to very high pH and osmotic pressure. Biodegradation of the concrete vaults housing the radioactive waste however, is a possibility. The rate and degree of concrete biodegradation is dependent on numerous physical, chemical and biological parameters. Results from this review point to parameters to focus on for modeling activities and also, possible options for mitigation that would minimize concrete biodegradation. In addition, key chemical components that drive microbial activity on concrete surfaces are discussed.« less

Technology advances needed for photovoltaics to achieve widespread grid price parity: Widespread grid price parity for photovoltaics

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

Jones-Albertus, Rebecca; Feldman, David; Fu, Ran

2016-04-20

To quantify the potential value of technological advances to the photovoltaics (PV) sector, this paper examines the impact of changes to key PV module and system parameters on the levelized cost of energy (LCOE). The parameters selected include module manufacturing cost, efficiency, degradation rate, and service lifetime. NREL's System Advisor Model (SAM) is used to calculate the lifecycle cost per kilowatt-hour (kWh) for residential, commercial, and utility scale PV systems within the contiguous United States, with a focus on utility scale. Different technological pathways are illustrated that may achieve the Department of Energy's SunShot goal of PV electricity that ismore » at grid price parity with conventional electricity sources. In addition, the impacts on the 2015 baseline LCOE due to changes to each parameter are shown. These results may be used to identify research directions with the greatest potential to impact the cost of PV electricity.« less

Testing cosmic transparency with the latest baryon acoustic oscillations and type Ia supernovae data

NASA Astrophysics Data System (ADS)

Chen, Jun; Wu, Pu-Xun; Yu, Hong-Wei; Li, Zheng-Xiang

2013-06-01

Observations show that Type Ia supernovae (SNe Ia) are dimmer than expected from a matter dominated Universe. It has been suggested that this observed phenomenon can also be explained using light absorption instead of dark energy. However, there is a serious degeneracy between the cosmic absorption parameter and the present matter density parameter Ωm when one tries to place constraints on the cosmic opacity using SNe Ia data. We combine the latest baryon acoustic oscillation (BAO) and Union2 SNe Ia data in order to break this degeneracy. Assuming a flat ΛCDM model, we find that, although an opaque Universe is favored by SNe Ia+BAO since the best fit value of the cosmic absorption parameter is larger than zero, Ωm = 1 is ruled out at the 99.7% confidence level. Thus, cosmic opacity is not sufficient to account for the present observations and dark energy or modified gravity is still required.

Determination of functions of controlling drives of main executive mechanisms of mining excavators

NASA Astrophysics Data System (ADS)

Lagunova, Yu A.; Komissarov, A. P.; Lukashuk, O. A.

2018-03-01

It is shown that a special shovel is a feature of the structure of the drives of the main mechanisms (mechanisms of lifting and pressure) of career excavators with working equipment, the presence in the transfer device of a two-crank-lever mechanism of working equipment that connects the main mechanisms with the working body (bucket). In this case, the transformation of the mechanical energy parameters of the motors into energy-force parameters realized at the cutting edge of the bucket (teeth) takes place depending on the type of the kinematic scheme of the two-link-lever mechanism. The concept of “control function” defining the relationship between the parameters characterizing the position of the bucket in the face (the coordinates of the tip of the cutting edge of the bucket, the digging speed) and the required control level are introduced. These are the values of the lifting and head speeds ensuring the bucket movement along a given trajectory.

`Relativistic' corrections to the mass of a plucked guitar string

NASA Astrophysics Data System (ADS)

Kolodrubetz, Michael; Polkovnikov, Anatoli

Quantum systems respond non-adiabaticity when parameters controlling them are ramped at a finite rate. If the parameters themselves are dynamical - for instance the position of a box that defines the boundary of a quantum field - the feedback of these excitations gives rise to effective Newtonian equations of motion for the parameter. For the age old problem of photons in a box, this correction gives rise to a mass proportional to the energy of the photons. We show that a similar correction arises for a classical guitar string plucked with energy E; moving clamps at the ends of the string requires inertial mass m = 2 E /cs2 , where cs is the speed of sound. This quasi-relativistic effect should be observable in freshman physics level experiments. We then comment on how these simple methods have been readily extended to treat problems such as ramps and quenches of strongly-interacting superconductors and dynamical trapping near a quantum critical point.

Polynomial solution of quantum Grassmann matrices

NASA Astrophysics Data System (ADS)

Tierz, Miguel

2017-05-01

We study a model of quantum mechanical fermions with matrix-like index structure (with indices N and L) and quartic interactions, recently introduced by Anninos and Silva. We compute the partition function exactly with q-deformed orthogonal polynomials (Stieltjes-Wigert polynomials), for different values of L and arbitrary N. From the explicit evaluation of the thermal partition function, the energy levels and degeneracies are determined. For a given L, the number of states of different energy is quadratic in N, which implies an exponential degeneracy of the energy levels. We also show that at high-temperature we have a Gaussian matrix model, which implies a symmetry that swaps N and L, together with a Wick rotation of the spectral parameter. In this limit, we also write the partition function, for generic L and N, in terms of a single generalized Hermite polynomial.

Assessing the sensitivity of a land-surface scheme to the parameter values using a single column model

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

Pitman, A.J.

The sensitivity of a land-surface scheme (the Biosphere Atmosphere Transfer Scheme, BATS) to its parameter values was investigated using a single column model. Identifying which parameters were important in controlling the turbulent energy fluxes, temperature, soil moisture, and runoff was dependent upon many factors. In the simulation of a nonmoisture-stressed tropical forest, results were dependent on a combination of reservoir terms (soil depth, root distribution), flux efficiency terms (roughness length, stomatal resistance), and available energy (albedo). If moisture became limited, the reservoir terms increased in importance because the total fluxes predicted depended on moisture availability and not on the ratemore » of transfer between the surface and the atmosphere. The sensitivity shown by BATS depended on which vegetation type was being simulated, which variable was used to determine sensitivity, the magnitude and sign of the parameter change, the climate regime (precipitation amount and frequency), and soil moisture levels and proximity to wilting. The interactions between these factors made it difficult to identify the most important parameters in BATS. Therefore, this paper does not argue that a particular set of parameters is important in BATS, rather it shows that no general ranking of parameters is possible. It is also emphasized that using `stand-alone` forcing to examine the sensitivity of a land-surface scheme to perturbations, in either parameters or the atmosphere, is unreliable due to the lack of surface-atmospheric feedbacks.« less

Level Densities of Residual Nuclei from particle evaporation of 64Cu

NASA Astrophysics Data System (ADS)

Oginni, B. M.; Grimes, S. M.; Voinov, A. V.; Adekola, A. S.; Brune, C. R.; Carter, D.; Heinen, Z.; Jacobs, D.; Massey, T. N.; O'Donnell, J.

2009-07-01

The reactions of 6Li on 58Fe and 7Li on 57Fe have been studied at beam energy 15 MeV. These two reactions produce the same compound nucleus, 64Cu. The neutron, proton, and alpha spectra were measured at backward angles. The data obtained have been compared with Hauser Fesh-bach model calculations. The level density parameters of the residual nuclei have been obtained from the particle evaporation spectra.

USING A PHENOMENOLOGICAL MODEL TO TEST THE COINCIDENCE PROBLEM OF DARK ENERGY

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

Chen Yun; Zhu Zonghong; Alcaniz, J. S.

2010-03-01

By assuming a phenomenological form for the ratio of the dark energy and matter densities rho{sub X} {proportional_to} rho{sub m} a {sup x}i, we discuss the cosmic coincidence problem in light of current observational data. Here, xi is a key parameter to denote the severity of the coincidence problem. In this scenario, xi = 3 and xi = 0 correspond to LAMBDACDM and the self-similar solution without the coincidence problem, respectively. Hence, any solution with a scaling parameter 0 < xi < 3 makes the coincidence problem less severe. In addition, the standard cosmology without interaction between dark energy andmore » dark matter is characterized by xi + 3omega{sub X} = 0, where omega{sub X} is the equation of state of the dark energy component, whereas the inequality xi + 3omega{sub X} {ne} 0 represents non-standard cosmology. We place observational constraints on the parameters (OMEGA{sub X,0}, omega{sub X}, xi) of this model, where OMEGA{sub X,0} is the present value of density parameter of dark energy OMEGA{sub X}, by using the Constitution Set (397 supernovae of type Ia data, hereafter SNeIa), the cosmic microwave background shift parameter from the five-year Wilkinson Microwave Anisotropy Probe and the Sloan Digital Sky Survey baryon acoustic peak. Combining the three samples, we get OMEGA{sub X,0} = 0.72 +- 0.02, omega{sub X} = -0.98 +- 0.07, and xi = 3.06 +- 0.35 at 68.3% confidence level. The result shows that the LAMBDACDM model still remains a good fit to the recent observational data, and the coincidence problem indeed exists and is quite severe, in the framework of this simple phenomenological model. We further constrain the model with the transition redshift (deceleration/acceleration). It shows that if the transition from deceleration to acceleration happens at the redshift z > 0.73, within the framework of this model, we can conclude that the interaction between dark energy and dark matter is necessary.« less

Optimization of the level and range of working temperature of the PCM in the gypsum-microencapsulated PCM thermal energy storage unit for summer conditions in Central Poland

NASA Astrophysics Data System (ADS)

Łapka, P.; Jaworski, M.

2017-10-01

In this paper thermal energy storage (TES) unit in a form of a ceiling panel made of gypsum-microencapsulated PCM composite with internal U-shaped channels was considered and optimal characteristics of the microencapsulated PCM were determined. This panel may be easily incorporated into, e.g., an office or residential ventilation system in order to reduce daily variations of air temperature during the summer without additional costs related to the consumption of energy for preparing air parameters to the desired level. For the purpose of the analysis of heat transfer in the panel, a novel numerical simulator was developed. The numerical model consists of two coupled parts, i.e., the 1D which deals with the air flowing through the U-shaped channel and the 3D which deals with heat transfer in the body of the panel. The computational tool was validated based on the experimental study performed on the special set-up. Using this tool an optimization of parameters of the gypsum-microencapsulated PCM composite was performed in order to determine its most appropriate properties for the application under study. The analyses were performed for averaged local summer conditions in Warsaw, Poland.

Renormalized coupled cluster approaches in the cluster-in-molecule framework: predicting vertical electron binding energies of the anionic water clusters (H2O)(n)(-).

PubMed

Xu, Peng; Gordon, Mark S

2014-09-04

Anionic water clusters are generally considered to be extremely challenging to model using fragmentation approaches due to the diffuse nature of the excess electron distribution. The local correlation coupled cluster (CC) framework cluster-in-molecule (CIM) approach combined with the completely renormalized CR-CC(2,3) method [abbreviated CIM/CR-CC(2,3)] is shown to be a viable alternative for computing the vertical electron binding energies (VEBE). CIM/CR-CC(2,3) with the threshold parameter ζ set to 0.001, as a trade-off between accuracy and computational cost, demonstrates the reliability of predicting the VEBE, with an average percentage error of ∼15% compared to the full ab initio calculation at the same level of theory. The errors are predominantly from the electron correlation energy. The CIM/CR-CC(2,3) approach provides the ease of a black-box type calculation with few threshold parameters to manipulate. The cluster sizes that can be studied by high-level ab initio methods are significantly increased in comparison with full CC calculations. Therefore, the VEBE computed by the CIM/CR-CC(2,3) method can be used as benchmarks for testing model potential approaches in small-to-intermediate-sized water clusters.

Quantum chemical calculations of glycine glutaric acid

NASA Astrophysics Data System (ADS)

Arioǧlu, ćaǧla; Tamer, Ömer; Avci, Davut; Atalay, Yusuf

2017-02-01

Density functional theory (DFT) calculations of glycine glutaric acid were performed by using B3LYP levels with 6-311++G(d,p) basis set. The theoretical structural parameters such as bond lengths and bond angles are in a good agreement with the experimental values of the title compound. HOMO and LUMO energies were calculated, and the obtained energy gap shows that charge transfer occurs in the title compound. Vibrational frequencies were calculated and compare with experimental ones. 3D molecular surfaces of the title compound were simulated using the same level and basis set. Finally, the 13C and 1H NMR chemical shift values were calculated by the application of the gauge independent atomic orbital (GIAO) method.

Circuit model for single-energy-level trap centers in FETs

NASA Astrophysics Data System (ADS)

Albahrani, Sayed Ali; Parker, Anthony; Heimlich, Michael

2016-12-01

A circuit implementation of a single-energy-level trap center in an FET is presented. When included in transistor models it explains the temperature-potential-dependent time constants seen in the circuit manifestations of charge trapping, being gate lag and drain overshoot. The implementation is suitable for both time-domain and harmonic-balance simulations. The proposed model is based on the Shockley-Read-Hall (SRH) statistics of the trapping process. The results of isothermal pulse measurements performed on a GaN HEMT are presented. These measurement allow characterizing charge trapping in isolation from the effect of self-heating. These results are used to obtain the parameters of the proposed model.

Comparisons of Solar Wind Coupling Parameters with Auroral Energy Deposition Rates

NASA Technical Reports Server (NTRS)

Elsen, R.; Brittnacher, M. J.; Fillingim, M. O.; Parks, G. K.; Germany G. A.; Spann, J. F., Jr.

1997-01-01

Measurement of the global rate of energy deposition in the ionosphere via auroral particle precipitation is one of the primary goals of the Polar UVI program and is an important component of the ISTP program. The instantaneous rate of energy deposition for the entire month of January 1997 has been calculated by applying models to the UVI images and is presented by Fillingim et al. In this session. A number of parameters that predict the rate of coupling of solar wind energy into the magnetosphere have been proposed in the last few decades. Some of these parameters, such as the epsilon parameter of Perrault and Akasofu, depend on the instantaneous values in the solar wind. Other parameters depend on the integrated values of solar wind parameters, especially IMF Bz, e.g. applied flux which predicts the net transfer of magnetic flux to the tail. While these parameters have often been used successfully with substorm studies, their validity in terms of global energy input has not yet been ascertained, largely because data such as that supplied by the ISTP program was lacking. We have calculated these and other energy coupling parameters for January 1997 using solar wind data provided by WIND and other solar wind monitors. The rates of energy input predicted by these parameters are compared to those measured through UVI data and correlations are sought. Whether these parameters are better at providing an instantaneous rate of energy input or an average input over some time period is addressed. We also study if either type of parameter may provide better correlations if a time delay is introduced; if so, this time delay may provide a characteristic time for energy transport in the coupled solar wind-magnetosphere-ionosphere system.

Quenching And Luminescence Efficiency Of Nd3+ In YAG

NASA Astrophysics Data System (ADS)

Lupei, Voicu; Lupei, Aurelia; Georgescu, Serban; Ionescu, Christian I.; Yen, William M.

1989-05-01

The effect of the concentration luminescence quenching of the 4F 3/2, level of Nd3+ in YAG on the relative efficiency is presented. Based on the analysis of the decay curves in terms of the energy transfer theory, an analytical expression for the relative luminescence efficiency is obtained. In the low concentration range (up to q,1.5 at % Nd3+), the efficiency linearly decreases when Nd3+ concentration increases. It is also stressed that pairs quenching contribute about 20 % to the nonradiative energy transfer losses. Quantum efficiency of luminescence is an important parameter for the characterization of laser active media; its lowering is due to either multiphonon relaxation or energy transfer processes. The multiphonon non-radiative probability depends on the energy gap between levels, on the phonon energy and temperature; usually at low activator doping it is practically independent on concentration. On the other hand, energy transfer losses show a marked dependence on activator concentration, a fact that severely limits the range of useful con-centration of active centers in some laser crystals. In the YAG:Nd case the minimum energy gap between the Stark components of the 4F,I.) and the next lower level 4F15/2 is of about 4700 cm-1. Since in YAG tree phonons most effdbtively coupled to the Rare pi.th ions have an energy of 1, 700 cm-1, the probability for multiphonon relaxation from the 'F3/, level, even at room temperature, is very low and therefore for low Nd 3+ concentrations quantum efficiency is expected to be close to 1.

Energy dissipation in polymer-polymer adhesion contacts

NASA Astrophysics Data System (ADS)

Garif, Yev Skip

This study focuses on self-adhesion in elastomers as a way of approaching a broader polymer adhesion problem. The model systems studied are cross-linked acrylic pressure-sensitive adhesives (PSA-LNs) synthesized to attain four surface types: neutral, acidic, basic, and polar. As the study progressed, it distinguished itself as the first of its kind to consistently report the effect of temperature on measurable intrinsic parameters of polymer adhesion. The main goal of the study was to understand why the magnitude of the practical adhesion energies of the four PSA-LN systems tested varies disproportionately greater than their respective surface energies. To achieve this goal, continuous sweeps of adhesion energy as a function of rate of interfacial separation were performed using three different adhesion-probing techniques--- peel, micro-scratch, and normal contact. The answer was found in the sub-micron-per-second limit of separation rates. In approaching this limit, the power law behavior of adhesion gradually transitioned into a linear region of markedly weaker sensitivity to rate. Referred to as the "intrinsic window", this linear region was characterized by three parameters: (1) the intrinsic adhesion energy at zero rate of separation; (2) the intrinsic rate sensitivity equal to the proportionality constant of the linear fit; and (3) the critical separation rate in the middle of the transition to the power law. All three were found to be thermally activated. Activation energies suggested that interfacial processes are attributed mainly to dispersive and electrostatic molecular interactions such as hydrogen bonding or van der Waals attraction. Comparative analysis of the intrinsic window of the four PSA-LNs tested showed that an increase in the intrinsic adhesion energy associated with higher surface energy is inherently coupled with an increase in the intrinsic rate sensitivity and reduction in the critical separation rate. When combined, the three parameters reshape the intrinsic window such that the entire power-law portion of the adhesion response is shifted to a level that appears disproportionately high based on the false assumption that there is only one intrinsic parameter contributing to the shift. Thus, the goal of explaining this disproportionality was achieved.

Oxygenation-linked subunit interactions in human hemoglobin: analysis of linkage functions for constituent energy terms.

PubMed

Johnson, M L; Halvorson, H R; Ackers, G K

1976-11-30

Resolution of the linkage functions between oxygenation and subunit association-dissociation equilibria in human hemoglobin into the constituent microscopic terms has been explored by numerical simulation and least-squares analysis. The correlation properties between parameters has been studied using several choices of parameter sets in order to optimize resolution. It is found that, with currently available levels of experimental precision and ranges of variables, neither linkage function can provide sufficient resolution of all the desired energy terms. The most difficult quantities to resolve always include the dimer-tetramer association constant for unliganded hemoglobin and the oxygen binding constants to alphabeta dimers. A feasible experimental strategy for overcoming these difficulties lies in independent determination of the dimer-tetramer association constants for unliganded and fully oxygenated hemoglobin. These constants, in combination with the median lignad concentration, provide an estimate of the energy for total oxygenation of tetramers which is essentially independent of the other constituent energies. It is shown that if these separately determinable parameters are fixed, the remaining terms may be estimated to good accuracy using data which represents either linkage function. In general it is desirable to combine information from both types of experimental quantities. A previous paper (Mills, F.C., Johnson, M.L., and Ackers, G.K. (1976), Biochemestry, 15, the preceding paper in this issue) describes the experimental implementation of this strategy.

Structure for Storing Properties of Particles (PoP)

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

Patel, N. R.; Mattoon, C. M.; Beck, B. R.

2014-06-01

Some evaluated nuclear databases are critical for applications such as nuclear energy, nuclear medicine, homeland security, and stockpile stewardship. Particle masses, nuclear excitation levels, and other “Properties of Particles” are essential for making evaluated nuclear databases. Currently, these properties are obtained from various databases that are stored in outdated formats. Moreover, the “Properties of Particles” (PoP) structure is being designed that will allow storing all information for one or more particles in a single place, so that each evaluation, simulation, model calculation, etc. can link to the same data. Information provided in PoP will include properties of nuclei, gammas andmore » electrons (along with other particles such as pions, as evaluations extend to higher energies). Presently, PoP includes masses from the Atomic Mass Evaluation version 2003 (AME2003), and level schemes and gamma decays from the Reference Input Parameter Library (RIPL-3). The data are stored in a hierarchical structure. An example of how PoP stores nuclear masses and energy levels will be presented here.« less

Structure for Storing Properties of Particles (PoP)

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

Patel, N.R., E-mail: infinidhi@llnl.gov; Mattoon, C.M.; Beck, B.R.

2014-06-15

Evaluated nuclear databases are critical for applications such as nuclear energy, nuclear medicine, homeland security, and stockpile stewardship. Particle masses, nuclear excitation levels, and other “Properties of Particles” are essential for making evaluated nuclear databases. Currently, these properties are obtained from various databases that are stored in outdated formats. A “Properties of Particles” (PoP) structure is being designed that will allow storing all information for one or more particles in a single place, so that each evaluation, simulation, model calculation, etc. can link to the same data. Information provided in PoP will include properties of nuclei, gammas and electrons (alongmore » with other particles such as pions, as evaluations extend to higher energies). Presently, PoP includes masses from the Atomic Mass Evaluation version 2003 (AME2003), and level schemes and gamma decays from the Reference Input Parameter Library (RIPL-3). The data are stored in a hierarchical structure. An example of how PoP stores nuclear masses and energy levels will be presented here.« less

Electronic states and optical properties of single donor in GaN conical quantum dot with spherical edge

NASA Astrophysics Data System (ADS)

El Aouami, A.; Feddi, E.; El-Yadri, M.; Aghoutane, N.; Dujardin, F.; Duque, C. A.; Phuc, Huynh Vinh

2018-02-01

In this paper we present a theoretical investigation of quantum confinement effects on the electron and single donor states in GaN conical quantum dot with spherical edge. In the framework of the effective mass approximation, the Schrödinger equations of electron and donor have been solved analytically in an infinite potential barrier model. Our calculations show that the energies of electron and donor impurity are affected by the two characteristic parameters of the structure which are the angle Ω and the radial dimension R. We show that, despite the fact that the reduction of the two parameters Ω and R leads to the same confinement effects, the energy remains very sensitive to the variation of the radial part than the variation of the angular part. The analysis of the photoionization cross-section corresponding to optical transitions between the conduction band and the first donor energy level shows clearly that the reduction of the radius R causes a shift in resonance peaks towards the high energies. On the other hand, the optical transitions between 1 s - 1 p , 1 p - 1 d and 1 p - 2 s show that the increment of the conical aperture Ω (or reduction of R) implies a displacement of the excitation energy to higher energies.

Effects of Extrinsic Mortality on the Evolution of Aging: A Stochastic Modeling Approach

PubMed Central

Shokhirev, Maxim Nikolaievich; Johnson, Adiv Adam

2014-01-01

The evolutionary theories of aging are useful for gaining insights into the complex mechanisms underlying senescence. Classical theories argue that high levels of extrinsic mortality should select for the evolution of shorter lifespans and earlier peak fertility. Non-classical theories, in contrast, posit that an increase in extrinsic mortality could select for the evolution of longer lifespans. Although numerous studies support the classical paradigm, recent data challenge classical predictions, finding that high extrinsic mortality can select for the evolution of longer lifespans. To further elucidate the role of extrinsic mortality in the evolution of aging, we implemented a stochastic, agent-based, computational model. We used a simulated annealing optimization approach to predict which model parameters predispose populations to evolve longer or shorter lifespans in response to increased levels of predation. We report that longer lifespans evolved in the presence of rising predation if the cost of mating is relatively high and if energy is available in excess. Conversely, we found that dramatically shorter lifespans evolved when mating costs were relatively low and food was relatively scarce. We also analyzed the effects of increased predation on various parameters related to density dependence and energy allocation. Longer and shorter lifespans were accompanied by increased and decreased investments of energy into somatic maintenance, respectively. Similarly, earlier and later maturation ages were accompanied by increased and decreased energetic investments into early fecundity, respectively. Higher predation significantly decreased the total population size, enlarged the shared resource pool, and redistributed energy reserves for mature individuals. These results both corroborate and refine classical predictions, demonstrating a population-level trade-off between longevity and fecundity and identifying conditions that produce both classical and non-classical lifespan effects. PMID:24466165

Output improvement of Sg. Piah run-off river hydro-electric station with a new computed river flow-based control system

NASA Astrophysics Data System (ADS)

Jidin, Razali; Othman, Bahari

2013-06-01

The lower Sg. Piah hydro-electric station is a river run-off hydro scheme with generators capable of generating 55MW of electricity. It is located 30km away from Sg. Siput, a small town in the state of Perak, Malaysia. The station has two turbines (Pelton) to harness energy from water that flow through a 7km tunnel from a small intake dam. The trait of a run-off river hydro station is small-reservoir that cannot store water for a long duration; therefore potential energy carried by the spillage will be wasted if the dam level is not appropriately regulated. To improve the station annual energy output, a new controller based on the computed river flow has been installed. The controller regulates the dam level with an algorithm based on the river flow derived indirectly from the intake-dam water level and other plant parameters. The controller has been able to maintain the dam at optimum water level and regulate the turbines to maximize the total generation output.

Interactive effects of elevated temperature and CO2 levels on energy metabolism and biomineralization of marine bivalves Crassostrea virginica and Mercenaria mercenaria.

PubMed

Ivanina, Anna V; Dickinson, Gary H; Matoo, Omera B; Bagwe, Rita; Dickinson, Ashley; Beniash, Elia; Sokolova, Inna M

2013-09-01

The continuing increase of carbon dioxide (CO2) levels in the atmosphere leads to increases in global temperatures and partial pressure of CO2 (PCO2) in surface waters, causing ocean acidification. These changes are especially pronounced in shallow coastal and estuarine waters and are expected to significantly affect marine calcifiers including bivalves that are ecosystem engineers in estuarine and coastal communities. To elucidate potential effects of higher temperatures and PCO2 on physiology and biomineralization of marine bivalves, we exposed two bivalve species, the eastern oysters Crassostrea virginica and the hard clams Mercenaria mercenaria to different combinations of PCO2 (~400 and 800μatm) and temperatures (22 and 27°C) for 15weeks. Survival, bioenergetic traits (tissue levels of lipids, glycogen, glucose and high energy phosphates) and biomineralization parameters (mechanical properties of the shells and activity of carbonic anhydrase, CA) were determined in clams and oysters under different temperature and PCO2 regimes. Our analysis showed major inter-species differences in shell mechanical traits and bioenergetics parameters. Elevated temperature led to the depletion of tissue energy reserves indicating energy deficiency in both species and resulted in higher mortality in oysters. Interestingly, while elevated PCO2 had a small effect on the physiology and metabolism of both species, it improved survival in oysters. At the same time, a combination of high temperature and elevated PCO2 lead to a significant decrease in shell hardness in both species, suggesting major changes in their biomineralization processes. Overall, these studies show that global climate change and ocean acidification might have complex interactive effects on physiology, metabolism and biomineralization in coastal and estuarine marine bivalves. Copyright © 2013 Elsevier Inc. All rights reserved.

Energy minimization of mobile video devices with a hardware H.264/AVC encoder based on energy-rate-distortion optimization

NASA Astrophysics Data System (ADS)

Kang, Donghun; Lee, Jungeon; Jung, Jongpil; Lee, Chul-Hee; Kyung, Chong-Min

2014-09-01

In mobile video systems powered by battery, reducing the encoder's compression energy consumption is critical to prolong its lifetime. Previous Energy-rate-distortion (E-R-D) optimization methods based on a software codec is not suitable for practical mobile camera systems because the energy consumption is too large and encoding rate is too low. In this paper, we propose an E-R-D model for the hardware codec based on the gate-level simulation framework to measure the switching activity and the energy consumption. From the proposed E-R-D model, an energy minimizing algorithm for mobile video camera sensor have been developed with the GOP (Group of Pictures) size and QP(Quantization Parameter) as run-time control variables. Our experimental results show that the proposed algorithm provides up to 31.76% of energy consumption saving while satisfying the rate and distortion constraints.

Rotational Parameters from Vibronic Eigenfunctions of Jahn-Teller Active Molecules

NASA Astrophysics Data System (ADS)

Garner, Scott M.; Miller, Terry A.

2017-06-01

The structure in rotational spectra of many free radical molecules is complicated by Jahn-Teller distortions. Understanding the magnitudes of these distortions is vital to determining the equilibrium geometric structure and details of potential energy surfaces predicted from electronic structure calculations. For example, in the recently studied {\\widetilde{A}^2E^{''} } state of the NO_3 radical, the magnitudes of distortions are yet to be well understood as results from experimental spectroscopic studies of its vibrational and rotational structure disagree with results from electronic structure calculations of the potential energy surface. By fitting either vibrationally resolved spectra or vibronic levels determined by a calculated potential energy surface, we obtain vibronic eigenfunctions for the system as linear combinations of basis functions from products of harmonic oscillators and the degenerate components of the electronic state. Using these vibronic eigenfunctions we are able to predict parameters in the rotational Hamiltonian such as the Watson Jahn-Teller distortion term, h_1, and compare with the results from the analysis of rotational experiments.

Electronic and Structural Parameters of Phosphorus-Oxygen Bonds in Inorganic Phosphate Crystals

NASA Astrophysics Data System (ADS)

Atuchin, V. V.; Kesler, V. G.; Pervukhina, N. V.

Wide set of experimental results on binding energy of photoelectrons emitted from P 2p, P 2s, and O 1s core levels has been observed for inorganic phosphate crystals and the parameters were compared using energy differences Δ(O 1s - P 2p) and Δ (O 1s - P 2s) as most robust characteristics. Linear dependence of the binding energy difference on mean chemical bond length L(P-O) between phosphorus and oxygen atoms has been found. The functions are of the forms: Δ (O 1s - P 2p) (eV) = 375.54 + 0.146 · L(P-O) (pm) and Δ (O 1s - P 2s) (eV) = 320.77 + 0.129 · L(P-O) (pm). The dependencies are general for inorganic phosphates and may be used in quantitative component analysis of X-ray photoemission spectra of complex oxide compounds including functional groups with different coordination of P and O atoms.

Empirical Equation Based Chirality (n, m) Assignment of Semiconducting Single Wall Carbon Nanotubes from Resonant Raman Scattering Data

PubMed Central

Arefin, Md Shamsul

2012-01-01

This work presents a technique for the chirality (n, m) assignment of semiconducting single wall carbon nanotubes by solving a set of empirical equations of the tight binding model parameters. The empirical equations of the nearest neighbor hopping parameters, relating the term (2n− m) with the first and second optical transition energies of the semiconducting single wall carbon nanotubes, are also proposed. They provide almost the same level of accuracy for lower and higher diameter nanotubes. An algorithm is presented to determine the chiral index (n, m) of any unknown semiconducting tube by solving these empirical equations using values of radial breathing mode frequency and the first or second optical transition energy from resonant Raman spectroscopy. In this paper, the chirality of 55 semiconducting nanotubes is assigned using the first and second optical transition energies. Unlike the existing methods of chirality assignment, this technique does not require graphical comparison or pattern recognition between existing experimental and theoretical Kataura plot. PMID:28348319

Unique spin-polarized transmission effects in a QD ring structure

NASA Astrophysics Data System (ADS)

Hedin, Eric; Joe, Yong

2010-10-01

Spintronics is an emerging field in which the spin of the electron is used for switching purposes and to communicate information. In order to obtain spin-polarized electron transmission, the Zeeman effect is employed to produce spin-split energy states in quantum dots which are embedded in the arms of a mesoscopic Aharonov-Bohm (AB) ring heterostructure. The Zeeman splitting of the QD energy levels can be induced by a parallel magnetic field, or by a perpendicular field which also produces AB-effects. The combination of these effects on the transmission resonances of the structure is studied analytically and several parameter regimes are identified which produce a high degree of spin-polarized output. Contour and line plots of the weighted spin polarization as a function of electron energy and magnetic field are presented to visualize the degree of spin-polarization. Taking advantage of these unique parameter regimes shows the potential promise of such devices for producing spin-polarized currents.

Second and third harmonic generation associated to infrared transitions in a Morse quantum well under applied electric and magnetic fields

NASA Astrophysics Data System (ADS)

Restrepo, R. L.; Kasapoglu, E.; Sakiroglu, S.; Ungan, F.; Morales, A. L.; Duque, C. A.

2017-09-01

The effects of electric and magnetic fields on the second and third harmonic generation coefficients in a Morse potential quantum well are theoretically studied. The energy levels and corresponding wave functions are obtained by solving the Schrödinger equation for the electron in the parabolic band scheme and effective mass approximations and the envelope function approach. The results show that both the electric and the magnetic fields have significant influence on the magnitudes and resonant peak energy positions of the second and third harmonic generation responses. In general, the Morse potential profile becomes wider and shallower as γ -parameter increases and so the energies of the bound states will be functions of this parameter. Therefore, we can conclude that the effects of the electric and magnetic fields can be used to tune and control the optical properties of interest in the range of the infrared electromagnetic spectrum.

Infrared Emission Spectrum of the Hydroxyl Radical: A Novel Experiment in Molecular Spectroscopy.

ERIC Educational Resources Information Center

Henderson, Giles; And Others

1982-01-01

Describes an experiment in which parameters from an "ab-initio" potential are used to calculate vibrational-rotational energy levels and construct a "stick spectrum" for the overtone emission of the hydroxyl radical. Provides background information on ab-initio spectrum, experimental procedures, and analysis of data. (Author/JN)

Analytical ground state for the Jaynes-Cummings model with ultrastrong coupling

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

Zhang Yuanwei; Institute of Theoretical Physics, Shanxi University, Taiyuan 030006; Chen Gang

2011-06-15

We present a generalized variational method to analytically obtain the ground-state properties of the Jaynes-Cummings model with the ultrastrong coupling. An explicit expression for the ground-state energy, which agrees well with the numerical simulation in a wide range of the experimental parameters, is given. In particular, the introduced method can successfully solve this Jaynes-Cummings model with the positive detuning (the atomic resonant level is larger than the photon frequency), which cannot be treated in the adiabatical approximation and the generalized rotating-wave approximation. Finally, we also demonstrate analytically how to control the mean photon number by means of the current experimentalmore » parameters including the photon frequency, the coupling strength, and especially the atomic resonant level.« less

Evaluating the environmental fate of pharmaceuticals using a level III model based on poly-parameter linear free energy relationships.

PubMed

Zukowska, Barbara; Breivik, Knut; Wania, Frank

2006-04-15

We recently proposed how to expand the applicability of multimedia models towards polar organic chemicals by expressing environmental phase partitioning with the help of poly-parameter linear free energy relationships (PP-LFERs). Here we elaborate on this approach by applying it to three pharmaceutical substances. A PP-LFER-based version of a Level III fugacity model calculates overall persistence, concentrations and intermedia fluxes of polar and non-polar organic chemicals between air, water, soil and sediments at steady-state. Illustrative modeling results for the pharmaceuticals within a defined coastal region are presented and discussed. The model results are highly sensitive to the degradation rate in water and the equilibrium partitioning between organic carbon and water, suggesting that an accurate description of this particular partitioning equilibrium is essential in order to obtain reliable predictions of environmental fate. The PP-LFER based modeling approach furthermore illustrates that the greatest mobility in aqueous phases may be experienced by pharmaceuticals that combines a small molecular size with strong H-acceptor properties.

Rocking curve imaging of high quality sapphire crystals in backscattering geometry

DOE PAGES

Jafari, A.; European Synchrotron Radiation Facility; Univ. of Liege,; ...

2017-01-23

Here, we report on the characterization of high quality sapphire single crystals suitable for high-resolution X-ray optics at high energy. Investigations using rocking curve imaging reveal the crystals to be of uniformly good quality at the level of ~10 -4 in lattice parameter variations, deltad/d. But, investigations using backscattering rocking curve imaging with lattice spacing resolution of deltad/d ~ 5.10 -8 shows very diverse quality maps for all crystals. Our results highlight nearly ideal areas with edge length of 0.2-0.5 mm in most crystals, but a comparison of the back re ection peak positions shows that even neighboring ideal areasmore » exhibit a relative difference in the lattice parameters on the order of deltad/d = 10-20.10 -8; this is several times larger than the rocking curve width. Furthermore, the stress-strain analysis suggests that an extremely stringent limit on the strain at a level of ~100 kPa in the growth process is required in order to produce crystals with large areas of the quality required for X-ray optics at high energy.« less

Megavoltage cargo radiography with dual energy material decomposition

NASA Astrophysics Data System (ADS)

Shikhaliev, Polad M.

2018-02-01

Megavoltage (MV) radiography has important applications in imaging large cargos for detecting illicit materials. A useful feature of MV radiography is the possibility of decomposing and quantifying materials with different atomic numbers. This can be achieved by imaging cargo at two different X-ray energies, or dual energy (DE) radiography. The performance of both single energy and DE radiography depends on beam energy, beam filtration, radiation dose, object size, and object content. The purpose of this work was to perform comprehensive qualitative and quantitative investigations of the image quality in MV radiography depending on the above parameters. A digital phantom was designed including Fe background with thicknesses of 2cm, 6cm, and 18cm, and materials samples of Polyethylene, Fe, Pb, and U. The single energy images were generated at x-ray beam energies 3.5MV, 6MV, and 9MV. The DE material decomposed images were generated using interlaced low and high energy beams 3.5/6MV and 6/9MV. The X-ray beams were filtered by low-Z (Polyethylene) and high-Z (Pb) filters with variable thicknesses. The radiation output of the accelerator was kept constant for all beam energies. The image quality metrics was signal-to-noise ratio (SNR) of the particular sample over a particular background. It was found that the SNR depends on the above parameters in a complex way, but can be optimized by selecting a particular set of parameters. For some imaging setups increased filter thicknesses, while strongly absorbing the beams, increased the SNR of material decomposed images. Beam hardening due to polyenergetic x-ray spectra resulted in material decomposition errors, but this could be addressed using region of interest decomposition. It was shown that it is not feasible to separate the materials with close atomic numbers using the DE method. Particularly, Pb and U were difficult to decompose, at least at the dose levels allowed by radiation source and safety requirements.

Rotational characterization of methyl methacrylate: Internal dynamics and structure determination

NASA Astrophysics Data System (ADS)

Herbers, Sven; Wachsmuth, Dennis; Obenchain, Daniel A.; Grabow, Jens-Uwe

2018-01-01

Rotational constants, Watson's S centrifugal distortion coefficients, and internal rotation parameters of the two most stable conformers of methyl methacrylate were retrieved from the microwave spectrum. Splittings of rotational energy levels were caused by two non equivalent methyl tops. Constraining the centrifugal distortion coefficients and internal rotation parameters to the values of the main isotopologues, the rotational constants of all single substituted 13C and 18O isotopologues were determined. From these rotational constants the substitution structures and semi-empirical zero point structures of both conformers were precisely determined.

Observational tests of non-adiabatic Chaplygin gas

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

Carneiro, S.; Pigozzo, C., E-mail: saulo.carneiro@pq.cnpq.br, E-mail: cpigozzo@ufba.br

2014-10-01

In a previous paper [1] it was shown that any dark sector model can be mapped into a non-adiabatic fluid formed by two interacting components, one with zero pressure and the other with equation-of-state parameter ω = -1. It was also shown that the latter does not cluster and, hence, the former is identified as the observed clustering matter. This guarantees that the dark matter power spectrum does not suffer from oscillations or instabilities. It applies in particular to the generalised Chaplygin gas, which was shown to be equivalent to interacting models at both background and perturbation levels. In the present papermore » we test the non-adiabatic Chaplygin gas against the Hubble diagram of type Ia supernovae, the position of the first acoustic peak in the anisotropy spectrum of the cosmic microwave background and the linear power spectrum of large scale structures. We consider two different compilations of SNe Ia, namely the Constitution and SDSS samples, both calibrated with the MLCS2k2 fitter, and for the power spectrum we use the 2dFGRS catalogue. The model parameters to be adjusted are the present Hubble parameter, the present matter density and the Chaplygin gas parameter α. The joint analysis best fit gives α ≈ - 0.5, which corresponds to a constant-rate energy flux from dark energy to dark matter, with the dark energy density decaying linearly with the Hubble parameter. The ΛCDM model, equivalent to α = 0, stands outside the 3σ confidence interval.« less

Improved continuum lowering calculations in screened hydrogenic model with l-splitting for high energy density systems

NASA Astrophysics Data System (ADS)

Ali, Amjad; Shabbir Naz, G.; Saleem Shahzad, M.; Kouser, R.; Aman-ur-Rehman; Nasim, M. H.

2018-03-01

The energy states of the bound electrons in high energy density systems (HEDS) are significantly affected due to the electric field of the neighboring ions. Due to this effect bound electrons require less energy to get themselves free and move into the continuum. This phenomenon of reduction in potential is termed as ionization potential depression (IPD) or the continuum lowering (CL). The foremost parameter to depict this change is the average charge state, therefore accurate modeling for CL is imperative in modeling atomic data for computation of radiative and thermodynamic properties of HEDS. In this paper, we present an improved model of CL in the screened hydrogenic model with l-splitting (SHML) proposed by G. Faussurier and C. Blancard, P. Renaudin [High Energy Density Physics 4 (2008) 114] and its effect on average charge state. We propose the level charge dependent calculation of CL potential energy and inclusion of exchange and correlation energy in SHML. By doing this, we made our model more relevant to HEDS and free from CL empirical parameter to the plasma environment. We have implemented both original and modified model of SHML in our code named OPASH and benchmark our results with experiments and other state-of-the-art simulation codes. We compared our results of average charge state for Carbon, Beryllium, Aluminum, Iron and Germanium against published literature and found a very reasonable agreement between them.

Impact of anti-charge sharing on the zero-frequency detective quantum efficiency of CdTe-based photon counting detector system: cascaded systems analysis and experimental validation

NASA Astrophysics Data System (ADS)

Ji, Xu; Zhang, Ran; Chen, Guang-Hong; Li, Ke

2018-05-01

Inter-pixel communication and anti-charge sharing (ACS) technologies have been introduced to photon counting detector (PCD) systems to address the undesirable charge sharing problem. In addition to improving the energy resolution of PCD, ACS may also influence other aspects of PCD performance such as detector multiplicity (i.e. the number of pixels triggered by each interacted photon) and detective quantum efficiency (DQE). In this work, a theoretical model was developed to address how ACS impacts the multiplicity and zero-frequency DQE [DQE(0)] of PCD systems. The work focused on cadmium telluride (CdTe)-based PCD that often involves the generation and transport of K-fluorescence photons. Under the parallel cascaded systems analysis framework, the theory takes both photoelectric and scattering effects into account, and it also considers both the reabsorption and escape of photons. In a new theoretical treatment of ACS, it was considered as a modified version of the conventional single pixel (i.e. non-ACS) mode, but with reduced charge spreading distance and K-fluorescence travel distance. The proposed theoretical model does not require prior knowledge of the detailed ACS implementation method for each specific PCD, and its parameters can be experimentally determined using a radioisotope without invoking any Monte-Carlo simulation. After determining the model parameters, independent validation experiments were performed using a diagnostic x-ray tube and four different polychromatic beams (from 50 to 120 kVp). Both the theoretical and experimental results demonstrate that ACS increased the first and second moments of multiplicity for a majority of the x-ray energy and threshold levels tested, except when the threshold level was much lower than the x-ray energy level. However, ACS always improved DQE(0) at all energy and threshold levels tested.

Cost-Effective Method for Free-Energy Minimization in Complex Systems with Elaborated Ab Initio Potentials.

PubMed

Bistafa, Carlos; Kitamura, Yukichi; Martins-Costa, Marilia T C; Nagaoka, Masataka; Ruiz-López, Manuel F

2018-06-12

We describe a method to locate stationary points in the free-energy hypersurface of complex molecular systems using high-level correlated ab initio potentials. In this work, we assume a combined QM/MM description of the system although generalization to full ab initio potentials or other theoretical schemes is straightforward. The free-energy gradient (FEG) is obtained as the mean force acting on relevant nuclei using a dual level strategy. First, a statistical simulation is carried out using an appropriate, low-level quantum mechanical force-field. Free-energy perturbation (FEP) theory is then used to obtain the free-energy derivatives for the target, high-level quantum mechanical force-field. We show that this composite FEG-FEP approach is able to reproduce the results of a standard free-energy minimization procedure with high accuracy, while simultaneously allowing for a drastic reduction of both computational and wall-clock time. The method has been applied to study the structure of the water molecule in liquid water at the QCISD/aug-cc-pVTZ level of theory, using the sampling from QM/MM molecular dynamics simulations at the B3LYP/6-311+G(d,p) level. The obtained values for the geometrical parameters and for the dipole moment of the water molecule are within the experimental error, and they also display an excellent agreement when compared to other theoretical estimations. The developed methodology represents therefore an important step toward the accurate determination of the mechanism, kinetics, and thermodynamic properties of processes in solution, in enzymes, and in other disordered chemical systems using state-of-the-art ab initio potentials.

Fluorescence properties and energy transfer study of Er3+/Nd3+ doped fluorophosphate glass pumped at 800 and 980 nm for mid-infrared laser applications

NASA Astrophysics Data System (ADS)

Tian, Ying; Xu, Rongrong; Hu, Lili; Zhang, Junjie

2012-04-01

The fluorescence properties of 2.7 μm emission as well as near infrared emissions in Er3+/Nd3+ doped fluorophosphate glasses are investigated under 800 and 980 nm excitation. The fluorescence dynamics and energy transfer processes between Er and Nd ions in different pumping schemes are reported. Three Judd-Ofelt intensity parameters, energy transfer microparameters, and efficiency have been determined using the Judd-Ofelt and Förster-Dexter theories. The calculated energy transfer efficiency of the Er3+:4I13/2 level to the Nd3+:4I15/2 level is as high as 83.91%. The results indicate that Nd3+ may be an efficient sensitizer for Er3+ to obtain mid-infrared emission and the more suitable pumping scheme of 2.7 μm laser applications for Er3+/Nd3+ doped fluorophosphate glass is 980 nm excitation.

BOREAS Level-0 AOCI Imagery: Digital Counts in BIL Format

NASA Technical Reports Server (NTRS)

Newcomer, Jeffrey A.; Dominquez, Roseanne; Hall, Forrest G. (Editor)

2000-01-01

The level-0 AOCI imagery, along with the other remotely sensed images, was collected to provide spatially extensive information about radiant energy over the primary BOREAS study areas. The AOCI was the only remote sensing instrument flown with wavelength bands specific to the investigation of various aquatic parameters such as chlorophyll content and turbidity. Only one flight of the AOCI instrument was made onboard the ER-2 aircraft on 21-Jul-1994 over the SSA.

Thermoluminescence glow curve deconvolution and trapping parameters determination of dysprosium doped magnesium borate glass

NASA Astrophysics Data System (ADS)

Salama, E.; Soliman, H. A.

2018-07-01

In this paper, thermoluminescence glow curves of gamma irradiated magnesium borate glass doped with dysprosium were studied. The number of interfering peaks and in turn the number of electron trap levels are determined using the Repeated Initial Rise (RIR) method. At different heating rates (β), the glow curves were deconvoluted into two interfering peaks based on the results of RIR method. Kinetic parameters such as trap depth, kinetic order (b) and frequency factor (s) for each electron trap level is determined using the Peak Shape (PS) method. The obtained results indicated that, the magnesium borate glass doped with dysprosium has two electron trap levels with the average depth energies of 0.63 and 0.79 eV respectively. These two traps have second order kinetic and are formed at low temperature region. The obtained results due to the glow curve analysis could be used to explain some observed properties such as, high thermal fading and light sensitivity for such thermoluminescence material. In this work, systematic procedures to determine the kinetic parameters of any thermoluminescence material are successfully introduced.

In Vivo Fluorescence Resonance Energy Transfer Imaging for Targeted Anti-Cancer Drug Delivery Kinetics

NASA Astrophysics Data System (ADS)

Webb, Kevin; Gaind, Vaibhav; Tsai, Hsiaorho; Bentz, Brian; Chelvam, Venkatesh; Low, Philip

2012-02-01

We describe an approach for the evaluation of targeted anti-cancer drug delivery in vivo. The method emulates the drug release and activation process through acceptor release from a targeted donor-acceptor pair that exhibits fluorescence resonance energy transfer (FRET). In this case, folate targeting of the cancer cells is used - 40 % of all human cancers, including ovarian, lung, breast, kidney, brain and colon cancer, over-express folate receptors. We demonstrate the reconstruction of the spatially-dependent FRET parameters in a mouse model and in tissue phantoms. The FRET parameterization is incorporated into a source for a diffusion equation model for photon transport in tissue, in a variant of optical diffusion tomography (ODT) called FRET-ODT. In addition to the spatially-dependent tissue parameters in the diffusion model (absorption and diffusion coefficients), the FRET parameters (donor-acceptor distance and yield) are imaged as a function of position. Modulated light measurements are made with various laser excitation positions and a gated camera. More generally, our method provides a new vehicle for studying disease at the molecular level by imaging FRET parameters in deep tissue, and allows the nanometer FRET ruler to be utilized in deep tissue.

Energy Expenditure of Trotting Gait Under Different Gait Parameters

NASA Astrophysics Data System (ADS)

Chen, Xian-Bao; Gao, Feng

2017-07-01

Robots driven by batteries are clean, quiet, and can work indoors or in space. However, the battery endurance is a great problem. A new gait parameter design energy saving strategy to extend the working hours of the quadruped robot is proposed. A dynamic model of the robot is established to estimate and analyze the energy expenditures during trotting. Given a trotting speed, optimal stride frequency and stride length can minimize the energy expenditure. However, the relationship between the speed and the optimal gait parameters is nonlinear, which is difficult for practical application. Therefore, a simplified gait parameter design method for energy saving is proposed. A critical trotting speed of the quadruped robot is found and can be used to decide the gait parameters. When the robot is travelling lower than this speed, it is better to keep a constant stride length and change the cycle period. When the robot is travelling higher than this speed, it is better to keep a constant cycle period and change the stride length. Simulations and experiments on the quadruped robot show that by using the proposed gait parameter design approach, the energy expenditure can be reduced by about 54% compared with the 100 mm stride length under 500 mm/s speed. In general, an energy expenditure model based on the gait parameter of the quadruped robot is built and the trotting gait parameters design approach for energy saving is proposed.

Theoretical level energies and transition data for 4p64d4, 4p64d34f and 4p54d5 configurations of W34+ ion

NASA Astrophysics Data System (ADS)

Karpuškienė, R.; Bogdanovich, P.; Kisielius, R.

2017-05-01

The ab initio quasirelativistic approach developed specifically for the calculation of spectral parameters of highly charged ions was used to derive transition data for the tungsten ion W34+. The configuration interaction method was applied to include electron correlation effects. The relativistic effects were taken into account in the Breit-Pauli approximation. The level energies, radiative lifetimes τ, Landé g-factors are determined for the ground configuration 4p64d4 and two excited configurations 4p64d34f and 4p54d5. The radiative transition wavelengths λ and emission transition probabilities A for the electric dipole, electric quadrupole, electric octupole, magnetic dipole, and magnetic quadrupole transitions among the levels of these configurations are produced.

Effects of hydrostatic pressure on the donor impurity in a cylindrical quantum dot with Morse confining potential

NASA Astrophysics Data System (ADS)

Hayrapetyan, David B.; Kotanjyan, Tigran V.; Tevosyan, Hovhannes Kh.; Kazaryan, Eduard M.

2016-12-01

The effects of hydrostatic pressure and size quantization on the binding energies of a hydrogen-like donor impurity in cylindrical GaAs quantum dot (QD) with Morse confining potential are studied using the variational method and effective-mass approximation. In the cylindrical QD, the effect of hydrostatic pressure on the binding energy of electron has been investigated and it has been found that the application of the hydrostatic pressure leads to the blue shift. The dependence of the absorption edge on geometrical parameters of cylindrical QD is obtained. Selection rules are revealed for transitions between levels with different quantum numbers. It is shown that for the radial quantum number, transitions are allowed between the levels with the same quantum numbers, and any transitions between different levels are allowed for the principal quantum number.

A system-level mathematical model for evaluation of power train performance of load-leveled electric-vehicles

NASA Technical Reports Server (NTRS)

Purohit, G. P.; Leising, C. J.

1984-01-01

The power train performance of load leveled electric vehicles can be compared with that of nonload leveled systems by use of a simple mathematical model. This method of measurement involves a number of parameters including the degree of load leveling and regeneration, the flywheel mechanical to electrical energy fraction, and efficiencies of the motor, generator, flywheel, and transmission. Basic efficiency terms are defined and representative comparisons of a variety of systems are presented. Results of the study indicate that mechanical transfer of energy into and out of the flywheel is more advantageous than electrical transfer. An optimum degree of load leveling may be achieved in terms of the driving cycle, battery characteristics, mode of mechanization, and the efficiency of the components. For state of the art mechanically coupled flyheel systems, load leveling losses can be held to a reasonable 10%; electrically coupled systems can have losses that are up to six times larger. Propulsion system efficiencies for mechanically coupled flywheel systems are predicted to be approximately the 60% achieved on conventional nonload leveled systems.

Resummation of divergent perturbation series: Application to the vibrational states of H2CO molecule

NASA Astrophysics Data System (ADS)

Duchko, A. N.; Bykov, A. D.

2015-10-01

Large-order Rayleigh-Schrödinger perturbation theory (RSPT) is applied to the calculation of anharmonic vibrational energy levels of H2CO molecule. We use the model of harmonic oscillators perturbed by anharmonic terms of potential energy. Since the perturbation series typically diverge due to strong couplings, we apply the algebraic approximation technique because of its effectiveness shown earlier by Goodson and Sergeev [J. Chem. Phys. 110, 8205 (1999); ibid. 124, 094111 (2006)] and in our previous articles [A. D. Bykov et al. Opt. Spectrosc. 114, 396 (2013); ibid. 116, 598 (2014)]. To facilitate the resummation of terms contributing to perturbed states, when resonance mixing between states is especially strong and perturbation series diverge very quick, we used repartition of the Hamiltonian by shifting the normal mode frequencies. Energy levels obtained by algebraic approximants were compared with the results of variational calculation. It was found that for low energy states (up to ˜5000 cm-1), algebraic approximants gave accurate values of energy levels, which were in excellent agreement with the variational method. For highly excited states, strong and multiple resonances complicate series resummation, but a suitable change of normal mode frequencies allows one to reduce the resonance mixing and to get accurate energy levels. The theoretical background of the problem of RSPT series divergence is discussed along with its numerical analysis. For these purposes, the vibrational energy is considered as a function of a complex perturbation parameter. Layout and classification of its singularities allow us to model the asymptotic behavior of the perturbation series and prove the robustness of the algorithm.

Systemic metabolic signaling in acute and chronic gastrointestinal inflammation of inflammatory bowel diseases.

PubMed

Karrasch, T; Obermeier, F; Straub, R H

2014-06-01

Acute and chronic intestinal inflammation stimulates innate and adaptive immune systems, thereby increasing energy demand of activated immune cells. Energy regulation by systemically released mediators is of critical importance for homeostasis. We wanted to find out how systemic metabolic mediators are affected during intestinal inflammation. A total of 123 patients suffering from Crohn's disease (CD), 76 patients with ulcerative colitis (UC), and 21 healthy controls were recruited. Patients receiving systemic steroids or therapy regimens including biologicals (anti-TNF) were excluded from the study. Serum levels of IL-6, CRP, insulin, glucose, free fatty acid, and RBP-4 were measured by ELISA and RIA. Intestinal inflammation was accompanied by elevated systemic inflammatory para-meters such as IL-6 and CRP in UC and CD and, concomitantly, with elevated insulin levels and increased insulin/glucose ratio in patients with UC. This indicates insulin resistance in liver, muscle, and fat. In addition, intestinal inflammation was associated with elevated levels of circulating free fatty acids in UC and CD, indicating an activation of the organism's appeal for energy-rich substrates (energy appeal reaction). RBP-4 serum levels were also high in acute and chronic intestinal inflammation in UC and CD, which can support insulin resistance. The organism's "energy appeal reaction" in response to acute and chronic inflammation provides free energy in the circulation, which is needed by inflammatory cells. A major mechanism of the redirection program is insulin resistance. New therapeutic strategies might be developed in the future, directly impacting on the storage and utilization of energy-rich fuels. © Georg Thieme Verlag KG Stuttgart · New York.

Resummation of divergent perturbation series: Application to the vibrational states of H2CO molecule.

PubMed

Duchko, A N; Bykov, A D

2015-10-21

Large-order Rayleigh-Schrödinger perturbation theory (RSPT) is applied to the calculation of anharmonic vibrational energy levels of H2CO molecule. We use the model of harmonic oscillators perturbed by anharmonic terms of potential energy. Since the perturbation series typically diverge due to strong couplings, we apply the algebraic approximation technique because of its effectiveness shown earlier by Goodson and Sergeev [J. Chem. Phys. 110, 8205 (1999); ibid. 124, 094111 (2006)] and in our previous articles [A. D. Bykov et al. Opt. Spectrosc. 114, 396 (2013); ibid. 116, 598 (2014)]. To facilitate the resummation of terms contributing to perturbed states, when resonance mixing between states is especially strong and perturbation series diverge very quick, we used repartition of the Hamiltonian by shifting the normal mode frequencies. Energy levels obtained by algebraic approximants were compared with the results of variational calculation. It was found that for low energy states (up to ∼5000 cm(-1)), algebraic approximants gave accurate values of energy levels, which were in excellent agreement with the variational method. For highly excited states, strong and multiple resonances complicate series resummation, but a suitable change of normal mode frequencies allows one to reduce the resonance mixing and to get accurate energy levels. The theoretical background of the problem of RSPT series divergence is discussed along with its numerical analysis. For these purposes, the vibrational energy is considered as a function of a complex perturbation parameter. Layout and classification of its singularities allow us to model the asymptotic behavior of the perturbation series and prove the robustness of the algorithm.

Observing Quantum Monodromy: AN Energy-Momentum Map Built from Experimentally-Determined Level Energies Obtained from the νb{7} Far-Infrared Band System of Ncncs

NASA Astrophysics Data System (ADS)

Tokaryk, Dennis W.; Ross, Stephen Cary; Winnewisser, Brenda P.; Winnewisser, Manfred; De Lucia, Frank C.; Billinghurst, Brant E.

2016-06-01

The concept of Quantum Monodromy (QM) provides a fresh insight into the structure of rovibrational levels in those flexible molecules for which a bending mode can carry the molecule through the linear configuration. To confirm the existence of QM in a molecule required the fruits of several strands of development: the formulation of the abstract mathematical concept of monodromy, including the exploration of its relevance to systems described by classical mechanics and its manifestation in quantum molecular applications; the development of the required spectroscopic technology and computer-aided assignment; and the development of a theoretical model to apply in fitting to the observed data. We present a timeline for each of these strands, converging in our initial confirmation of QM in NCNCS from pure rotational data alone. In that work a Generalised SemiRigid Bender (GSRB) Hamiltonian was fitted to the experimental rotational structure. Rovibrational energies calculated from the fitted GSRB parameters allowed us to construct an ``Energy-Momentum" map and confirm the presence of QM in NCNCS. In further experimental work at the Canadian Light Source Synchrotron we have identified a network of transitions directly connecting the relevant energy levels and thereby have produced a refined Energy Momentum map for NCNCS from experimental measurements alone. This map extends from the ground vibrational level to well above the potential energy barrier, beautifully illustrating the characteristic signature of QM in a system uncomplicated by interaction with other vibrational modes. B. P. Winnewisser et al., Phys. Rev. Lett. 95, 243002 (2005)

Recombinant methionyl human leptin administration activates signal transducer and activator of transcription 3 signaling in peripheral blood mononuclear cells in vivo and regulates soluble tumor necrosis factor-alpha receptor levels in humans with relative leptin deficiency.

PubMed

Chan, Jean L; Moschos, Stergios J; Bullen, John; Heist, Kathleen; Li, Xian; Kim, Young-Bum; Kahn, Barbara B; Mantzoros, Christos S

2005-03-01

Studies of congenital complete leptin deficiency in animals and humans support a role for leptin in regulating immune function. Whether acquired relative leptin deficiency affects immunological parameters in healthy humans remains unknown. We thus used experimental models of relative leptin deficiency and recombinant methionyl human leptin (r-metHuLeptin) administration in humans to investigate whether r-metHuLeptin would activate signaling pathways in peripheral blood mononuclear cells (PBMCs) and whether acquired relative leptin deficiency and/or increasing circulating leptin levels into the physiologic range would change PBMC subpopulations and cytokines important in the T-helper cell and systemic immune responses. We found that r-metHuLeptin administration to healthy humans activates signal transducer and activator of transcription-3 signaling in PBMCs in vivo. Neither short-term leptin deficiency, induced by 3-d complete fasting, nor physiologic r-metHuLeptin replacement for the same period of time had a major effect on PBMC subpopulations or serum cytokines in healthy men. In contrast, normalizing serum leptin levels over 8 wk in lean women with relative leptin deficiency for 5.1 +/- 1.4 yr (mean +/- se) due to chronic energy deficit increased soluble TNFalpha receptor levels, indicating activation of the TNFalpha system. These findings suggest that relative leptin deficiency due to more long-term energy deprivation is associated with defects in immunological parameters that may be corrected with exogenous r-metHuLeptin administration. Further studies are warranted to assess the implications of acquired relative hypoleptinemia and/or r-metHuLeptin administration on the immunosuppression associated with energy- and leptin-deficient states in humans.

Optimization of parameters of special asynchronous electric drives

NASA Astrophysics Data System (ADS)

Karandey, V. Yu; Popov, B. K.; Popova, O. B.; Afanasyev, V. L.

2018-03-01

The article considers the solution of the problem of parameters optimization of special asynchronous electric drives. The solution of the problem will allow one to project and create special asynchronous electric drives for various industries. The created types of electric drives will have optimum mass-dimensional and power parameters. It will allow one to realize and fulfill the set characteristics of management of technological processes with optimum level of expenses of electric energy, time of completing the process or other set parameters. The received decision allows one not only to solve a certain optimizing problem, but also to construct dependences between the optimized parameters of special asynchronous electric drives, for example, with the change of power, current in a winding of the stator or rotor, induction in a gap or steel of magnetic conductors and other parameters. On the constructed dependences, it is possible to choose necessary optimum values of parameters of special asynchronous electric drives and their components without carrying out repeated calculations.

Accurate study on the properties of spectral lines for Br-like W39+

NASA Astrophysics Data System (ADS)

Guo, X. L.; Li, M. C.; Si, R.; He, X. D.; Wang, K.; Dai, Z. T.; Liu, Y. M.; Zhang, H. J.; Chen, C. Y.

2018-01-01

As a primary candidate in tokamak plasmas, the spectroscopic parameters of tungsten ions have been studied extensively over the past decade. In this paper, we perform calculations of excitation energies, lifetimes, wavelengths and transition rates for all levels of the 4{s}24{p}5, 4{s}24{p}44d, and 4s4{p}6 configurations of {{{W}}}39+ by using the multiconfiguration Dirac-Hartree-Fock (MCDHF) method, and also the relativistic many-body perturbation theory (RMBPT) method. Detailed convergence studies on excitation energy from electron-correlation effects and relativistic effects are presented. It is necessary to include the core-valence correlation from deep lying subshells, e.g. 3d and 3p, to produce reliable atomic parameters. Results are compared with available theoretical and experimental work, and the accuracy of the results is confirmed.

Centrifugal distortion coefficients of asymmetric-top molecules: Reduction of the octic terms of the rotational Hamiltonian

NASA Astrophysics Data System (ADS)

Ramachandra Rao, Ch. V. S.

1983-11-01

The rotational Hamiltonian of an asymmetric-top molecule in its standard form, containing terms up to eighth degree in the components of the total angular momentum, is transformed by a unitary transformation with parameters Spqr to a reduced Hamiltonian so as to avoid the indeterminacies inherent in fitting the complete Hamiltonian to observed energy levels. Expressions are given for the nine determinable combinations of octic constants Θ' i ( i = 1 to 9) which are invariant under the unitary transformation. A method of reduction suitable for energy calculations by matrix diagonalization is considered. The relations between the coefficients of the transformed Hamiltonian, for suitable choice of the parameters Spqr, and those of the reduced Hamiltonian are given. This enables the determination of the nine octic constants Θ' i in terms of the experimental constants.

Soft-Rotator Coupled Channels Global Optical Potential for A=24-122 Mass Region Nuclides up to 200-MeV Incident Nucleon Energies

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

Soukhovitski, Efrem Sh.; Chiba, Satoshi; Lee, Jeong-Yeon

2005-05-24

A coupled-channels optical model with a coupling scheme based on nuclear wave functions of the soft-rotator model was applied to analyze experimental nucleon-nucleus interaction data for even-even nuclides with mass number A=24-122. We found that all the available data (total cross sections, angular distributions of elastically and inelastically scattered nucleons, and reaction cross sections) for these nuclides can be described to a good accuracy using an optical potential having smooth dependencies of potential values, radii, and diffuseness on the mass number. The individual properties of the target nuclides are accounted for by individuality of the nuclear Hamiltonian parameters, adjusted tomore » reproduce the low-lying collective level structure, Fermi energies, and deformation parameters.« less

Environmental Management vitrification activities

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

Krumrine, P.H.

1996-05-01

Both the Mixed Waste and Landfill Stabilization Focus Areas as part of the Office of Technology Development efforts within the Department of Energy`s (DOE) Environmental Management (EM) Division have been developing various vitrification technologies as a treatment approach for the large quantities of transuranic (TRU), TRU mixed and Mixed Low Level Wastes that are stored in either landfills or above ground storage facilities. The technologies being developed include joule heated, plasma torch, plasma arc, induction, microwave, combustion, molten metal, and in situ methods. There are related efforts going into development glass, ceramic, and slag waste form windows of opportunity formore » the diverse quantities of heterogeneous wastes needing treatment. These studies look at both processing parameters, and long term performance parameters as a function of composition to assure that developed technologies have the right chemistry for success.« less

Electronic structure of free and doped actinides: N and Z dependences of energy levels and electronic structure parameters

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

Kulagin, N.

2005-02-15

Theoretical study of electronic structure of antinide ions and its dependence on N and Z are presented in this paper. The main 5f{sup N} and excited 5f{sup N}n'l'{sup N'} configurations of actinides have been studied using Hartree-Fock-Pauli approximation. Results of calculations of radial integrals and the energy of X-ray lines for all 5f ions with electronic state AC{sup +1}-AC{sup +4} show approximate dependence on N and Z. A square of N and cubic of Z are ewalized for the primary electronic parameters of the actinides. Theoretical values of radial integrals for free actinides and for ions in a cluster AC{supmore » +n}:[L]{sub k} are compared, too.« less

Effect of diode low-level lasers on fibroblasts derived from human periodontal tissue: a systematic review of in vitro studies.

PubMed

Ren, Chong; McGrath, Colman; Jin, Lijian; Zhang, Chengfei; Yang, Yanqi

2016-09-01

This study aimed to systematically assess the parameter-specific effects of the diode low-level laser on human gingival fibroblasts (HGFs) and human periodontal ligament fibroblasts (HPDLFs). An extensive search was performed in major electronic databases including PubMed (1997), EMBASE (1947) and Web of Science (1956) and supplemented by hand search of reference lists and relevant laser journals for cell culture studies investigating the effect of diode low-level lasers on HGFs and HPDLFs published from January 1995 to December 2015. A total of 21 studies were included after screening 324 independent records, amongst which eight targeted HPDLFs and 13 focussed on HGFs. The diode low-level laser showed positive effects on promoting fibroblast proliferation and osteogenic differentiation and modulating cellular inflammation via changes in gene expression and the release of growth factors, bone-remodelling markers or inflammatory mediators in a parameter-dependent manner. Repeated irradiations with wavelengths in the red and near-infrared range and at an energy density below 16 J/cm(2) elicited favourable responses. However, considerable variations and weaknesses in the study designs and laser protocols limited the interstudy comparison and clinical transition. Current evidence showed that diode low-level lasers with adequate parameters stimulated the proliferation and modulated the inflammation of fibroblasts derived from human periodontal tissue. However, further in vitro studies with better designs and more appropriate study models and laser parameters are anticipated to provide sound evidence for clinical studies and practice.

Control of energy sweep and transverse beam motion in induction linacs

NASA Astrophysics Data System (ADS)

Turner, W. C.

1991-05-01

Recent interest in the electron induction accelerator has focussed on its application as a driver for high power radiation sources; free electron laser (FEL), relativistic klystron (RK) and cyclotron autoresonance maser (CARM). In the microwave regime where many successful experiments have been carried out, typical beam parameters are: beam energy 1 to 10 MeV, current 1 to 3 kA and pulse width 50 nsec. Radiation source applications impose conditions on electron beam quality, as characterized by three parameters; energy sweep, transverse beam motion and brightness. These conditions must be maintained for the full pulse duration to assure high efficiency conversion of beam power to radiation. The microwave FEL that has been analyzed in the greatest detail requires energy sweep less than (+ or -) 1 pct., transverse beam motion less than (+ or -) 1 mm and brightness approx. 1 x 10(exp 8)A/sq m sq rad. In the visible region the requirements on these parameters become roughly an order of magnitude more strigent. With the ETAII accelerator at LLNL the requirements were achieved for energy sweep, transverse beam motion and brightness. The recent data and the advances that have made the improved beam quality possible are discussed. The most important advances are: understanding of focussing magnetic field errors and improvements in alignment of the magnetic axis, a redesign of the high voltage pulse distribution system between the magnetic compression modulators and the accelerator cells, and exploitation of a beam tuning algorithm for minimizing transverse beam motion. The prospects are briefly described for increasing the pulse repetition frequency to the range of 5 kHz and a delayed feedback method of regulating beam energy over very long pulse bursts, thus making average power megawatt level microwave sources at 140 GHz and above a possibility.

Influence of processing conditions on apparent viscosity and system parameters during extrusion of distiller's dried grains-based snacks.

PubMed

Singha, Poonam; Muthukumarappan, Kasiviswanathan; Krishnan, Padmanaban

2018-01-01

A combination of different levels of distillers dried grains processed for food application (FDDG), garbanzo flour and corn grits were chosen as a source of high-protein and high-fiber extruded snacks. A four-factor central composite rotatable design was adopted to study the effect of FDDG level, moisture content of blends, extrusion temperature, and screw speed on the apparent viscosity, mass flow rate or MFR, torque, and specific mechanical energy or SME during the extrusion process. With increase in the extrusion temperature from 100 to 140°C, apparent viscosity, specific mechanical energy, and torque value decreased. Increase in FDDG level resulted in increase in apparent viscosity, SME and torque. FDDG had no significant effect (p > .5) on mass flow rate. SME also increased with increase in the screw speed which could be due to the higher shear rates at higher screw speeds. Screw speed and moisture content had significant negative effect ( p  <   .05) on the torque. The apparent viscosity of dough inside the extruder and the system parameters were affected by the processing conditions. This study will be useful for control of extrusion process of blends containing these ingredients for the development of high-protein high-fiber extruded snacks.

Ballistic parameters and trauma potential of pistol crossbows.

PubMed

Frank, Matthias; Schikorr, Wolfgang; Tesch, Ralf; Werner, Ronald; Hanisch, Steffen; Peters, Dieter; Ekkernkamp, Axel; Bockholdt, Britta; Seifert, Julia

2013-07-01

Hand-held pistol crossbows, which are smaller versions of conventional crossbows, have recently increased in popularity. Similar to conventional crossbows, life threatening injuries due to bolts discharged from pistol crossbows are reported in forensic and traumatological literature. While the ballistic background of conventional crossbows is comprehensively investigated, there are no investigations on the characteristic ballistic parameters (draw force, potential energy, recurve factor, kinetic energy, and efficiency) of pistol crossbows. Two hand-held pistol crossbows (Barnett Commando and Mini Cross Bow, rated draw force 362.9 N or 80 lbs) were tested. The maximum draw force was investigated using a dynamic tensile testing machine (TIRAtest 2705, TIRA GmbH). The potential energy was determined graphically by polynomial regression as area under the force-draw curve. External ballistic parameters of the bolts discharged from pistol crossbows were measured using a redundant ballistic speed measurement system (Dual-BMC 21a and Dual-LS 1000, Werner Mehl Kurzzeitmesstechnik). The average maximum draw force was 190.3 and 175.6 N for the Barnett and Mini Cross Bow, respectively. The corresponding total energy expended was 10.7 and 11 J, respectively. The recurve factor was calculated to be 0.705 and 1.044, respectively. Average bolt velocity was measured 43 up to 52 m/s. The efficiency was calculated up to 0.94. To conclude, this work provides the pending ballistic data on this special subgroup of crossbows which operate on a remarkable low kinetic energy level. Furthermore, it demonstrates that the nominal draw force pretended in the sales brochure is grossly exaggerated.

DFT and ab initio study of the unimolecular decomposition of the lowest singlet and triplet states of nitromethane

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

Manaa, M.R.; Fried, L.E.

1998-11-26

The fully optimized potential energy curves for the unimolecular decomposition of the lowest singlet and triplet states of nitromethane through the C-NO{sub 2} bond dissociation pathway are calculated using various DFT and high-level ab initio electronic structure methods. The authors perform gradient corrected density functional theory (DFT) and multiconfiguration self-consistent field (MCSCF) to conclusively demonstrate that the triplet state of nitromethane is bound. The adiabatic curve of this state exhibits a 33 kcal/mol energy barrier as determined at the MCSCF level. DFT methods locate this barrier at a shorter C-N bond distance with 12--16 kcal/mol lower energy than does MCSCF.more » In addition to MCSCF and DFT, quadratic configuration interactions with single and double substitutions (QCISD) calculations are also performed for the singlet curve. The potential energy profiles of this state predicted by FT methods based on Becke`s 1988 exchange functional differ by as much as 17 kcal/mol from the predictions of MCSCF and QCISD in the vicinity of the equilibrium structure. The computational methods predict bond dissociation energies 5--9 kcal/mol lower than the experimental value. DFT techniques based on Becke`s 3-parameter exchange functional show the best overall agreement with the higher level methods.« less

Sensitivity of Turbine-Height Wind Speeds to Parameters in Planetary Boundary-Layer and Surface-Layer Schemes in the Weather Research and Forecasting Model

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

Yang, Ben; Qian, Yun; Berg, Larry K.

We evaluate the sensitivity of simulated turbine-height winds to 26 parameters applied in a planetary boundary layer (PBL) scheme and a surface layer scheme of the Weather Research and Forecasting (WRF) model over an area of complex terrain during the Columbia Basin Wind Energy Study. An efficient sampling algorithm and a generalized linear model are used to explore the multiple-dimensional parameter space and quantify the parametric sensitivity of modeled turbine-height winds. The results indicate that most of the variability in the ensemble simulations is contributed by parameters related to the dissipation of the turbulence kinetic energy (TKE), Prandtl number, turbulencemore » length scales, surface roughness, and the von Kármán constant. The relative contributions of individual parameters are found to be dependent on both the terrain slope and atmospheric stability. The parameter associated with the TKE dissipation rate is found to be the most important one, and a larger dissipation rate can produce larger hub-height winds. A larger Prandtl number results in weaker nighttime winds. Increasing surface roughness reduces the frequencies of both extremely weak and strong winds, implying a reduction in the variability of the wind speed. All of the above parameters can significantly affect the vertical profiles of wind speed, the altitude of the low-level jet and the magnitude of the wind shear strength. The wind direction is found to be modulated by the same subset of influential parameters. Remainder of abstract is in attachment.« less

Impact of undamped and damped intramolecular vibrations on the efficiency of photosynthetic exciton energy transfer

NASA Astrophysics Data System (ADS)

Juhász, Imre Benedek; Csurgay, Árpád I.

2018-04-01

In recent years, the role of molecular vibrations in exciton energy transfer taking place during the first stage of photosynthesis attracted increasing interest. Here, we present a model formulated as a Lindblad-type master equation that enables us to investigate the impact of undamped and especially damped intramolecular vibrational modes on the exciton energy transfer, particularly its efficiency. Our simulations confirm the already reported effects that the presence of an intramolecular vibrational mode can compensate the energy detuning of electronic states, thus promoting the energy transfer; and, moreover, that the damping of such a vibrational mode (in other words, vibrational relaxation) can further enhance the efficiency of the process by generating directionality in the energy flow. As a novel result, we show that this enhancement surpasses the one caused by pure dephasing, and we present its dependence on various system parameters (time constants of the environment-induced relaxation and excitation processes, detuning of the electronic energy levels, frequency of the intramolecular vibrational modes, Huang-Rhys factors, temperature) in dimer model systems. We demonstrate that vibrational-relaxation-enhanced exciton energy transfer (VREEET) is robust against the change of these characteristics of the system and occurs in wide ranges of the investigated parameters. With simulations performed on a heptamer model inspired by the Fenna-Matthews-Olson (FMO) complex, we show that this mechanism can be even more significant in larger systems at T = 300 K. Our results suggests that VREEET might be prevalent in light-harvesting complexes.

Modeling Physiological Processes That Relate Toxicant Exposure and Bacterial Population Dynamics

PubMed Central

Klanjscek, Tin; Nisbet, Roger M.; Priester, John H.; Holden, Patricia A.

2012-01-01

Quantifying effects of toxicant exposure on metabolic processes is crucial to predicting microbial growth patterns in different environments. Mechanistic models, such as those based on Dynamic Energy Budget (DEB) theory, can link physiological processes to microbial growth. Here we expand the DEB framework to include explicit consideration of the role of reactive oxygen species (ROS). Extensions considered are: (i) additional terms in the equation for the “hazard rate” that quantifies mortality risk; (ii) a variable representing environmental degradation; (iii) a mechanistic description of toxic effects linked to increase in ROS production and aging acceleration, and to non-competitive inhibition of transport channels; (iv) a new representation of the “lag time” based on energy required for acclimation. We estimate model parameters using calibrated Pseudomonas aeruginosa optical density growth data for seven levels of cadmium exposure. The model reproduces growth patterns for all treatments with a single common parameter set, and bacterial growth for treatments of up to 150 mg(Cd)/L can be predicted reasonably well using parameters estimated from cadmium treatments of 20 mg(Cd)/L and lower. Our approach is an important step towards connecting levels of biological organization in ecotoxicology. The presented model reveals possible connections between processes that are not obvious from purely empirical considerations, enables validation and hypothesis testing by creating testable predictions, and identifies research required to further develop the theory. PMID:22328915

The Application of Some Hartree-Fock Model Calculation to the Analysis of Atomic and Free-Ion Optical Spectra

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

Hayhurst, Thomas Laine

1980-08-06

Techniques for applying ab-initio calculations to the is of atomic spectra are investigated, along with the relationship between the semi-empirical and ab-initio forms of Slater-Condon theory. Slater-Condon theory is reviewed with a focus on the essential features that lead to the effective Hamiltonians associated with the semi-empirical form of the theory. Ab-initio spectroscopic parameters are calculated from wavefunctions obtained via self-consistent field methods, while multi-configuration Hamiltonian matrices are constructed and diagonalized with computer codes written by Robert Cowan of Los Alamos Scientific Laboratory. Group theoretical analysis demonstrates that wavefunctions more general than Slater determinants (i.e. wavefunctions with radial correlations betweenmore » electrons) lead to essentially the same parameterization of effective Hamiltonians. In the spirit of this analysis, a strategy is developed for adjusting ab-initio values of the spectroscopic parameters, reproducing parameters obtained by fitting the corresponding effective Hamiltonian. Secondary parameters are used to "screen" the calculated (primary) spectroscopic parameters, their values determined by least squares. Extrapolations of the secondary parameters determined from analyzed spectra are attempted to correct calculations of atoms and ions without experimental levels. The adjustment strategy and extrapolations are tested on the K I sequence from K 0+ through Fe 7+, fitting to experimental levels for V 4+, and Cr 5+; unobserved levels and spectra are predicted for several members of the sequence. A related problem is also discussed: Energy levels of the Uranium hexahalide complexes, (UX 6) 2- for X= F, Cl, Br, and I, are fit to an effective Hamiltonian (the f 2 configuration in O h symmetry) with corrections proposed by Brian Judd.« less

SU-E-T-146: Beam Energy Spread Estimate Based On Bragg Peak Measurement

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

Anferov, V; Derenchuk, V; Moore, R

2015-06-15

Purpose: ProNova is installing and commissioning a two room proton therapy system in Knoxville, TN. Beam energy out of the 230MeV cyclotron was measured on Jan 24, 2015. Cyclotron beam was delivered into a Zebra multi layered IC detector calibrated in terms of penetration range in water. The analysis of the measured Bragg peak determines penetration range in water which can be subsequently converted into proton beam energy. We extended this analysis to obtain an estimate of the beam energy spread out of the cyclotron. Methods: Using Monte Carlo simulations we established the correlation between Bragg peak shape parameters (widthmore » at 50% and 80% dose levels, distal falloff) and penetration range for a monoenergetic proton beam. For large uniform field impinging on a small area detector, we observed linear dependence of each Bragg peak parameter on beam penetration range as shown in Figure A. Then we studied how this correlation changes when the shape of Bragg peak is distorted by the beam focusing conditions. As shown in Figure B, small field size or diverging beam cause Bragg peak deformation predominantly in the proximal region. The distal shape of the renormalized Bragg peaks stays nearly constant. This excludes usage of Bragg peak width parameters for energy spread estimates. Results: The measured Bragg peaks had an average distal falloff of 4.86mm, which corresponds to an effective range of 35.5cm for a monoenergetic beam. The 32.7cm measured penetration range is 2.8cm less. Passage of a 230MeV proton beam through a 2.8cm thick slab of water results in a ±0.56MeV energy spread. As a final check, we confirmed agreement between shapes of the measured Bragg peak and one generated by Monte-Carlo code for proton beam with 0.56 MeV energy spread. Conclusion: Proton beam energy spread can be estimated using Bragg peak analysis.« less

Klein-Gordon oscillator with position-dependent mass in the rotating cosmic string spacetime

NASA Astrophysics Data System (ADS)

Wang, Bing-Qian; Long, Zheng-Wen; Long, Chao-Yun; Wu, Shu-Rui

2018-02-01

A spinless particle coupled covariantly to a uniform magnetic field parallel to the string in the background of the rotating cosmic string is studied. The energy levels of the electrically charged particle subject to the Klein-Gordon oscillator are analyzed. Afterwards, we consider the case of the position-dependent mass and show how these energy levels depend on the parameters in the problem. Remarkably, it shows that for the special case, the Klein-Gordon oscillator coupled covariantly to a homogeneous magnetic field with the position-dependent mass in the rotating cosmic string background has the similar behaviors to the Klein-Gordon equation with a Coulomb-type configuration in a rotating cosmic string background in the presence of an external magnetic field.

Finsler-type modification of the Coulomb law

NASA Astrophysics Data System (ADS)

Itin, Yakov; Lämmerzahl, Claus; Perlick, Volker

2014-12-01

Finsler geometry is a natural generalization of pseudo-Riemannian geometry. It can be motivated e.g. by a modified version of the Ehlers-Pirani-Schild axiomatic approach to space-time theory. Also, some scenarios of quantum gravity suggest a modified dispersion relation which could be phrased in terms of Finsler geometry. On a Finslerian space-time, the universality of free fall is still satisfied but local Lorentz invariance is violated in a way not covered by standard Lorentz invariance violation schemes. In this paper we consider a Finslerian modification of Maxwell's equations. The corrections to the Coulomb potential and to the hydrogen energy levels are computed. We find that the Finsler metric corrections yield a splitting of the energy levels. Experimental data provide bounds for the Finsler parameters.

Reduction of lighting energy consumption in office buildings through improved daylight design

NASA Astrophysics Data System (ADS)

Papadouri, Maria Violeta Prado

This study aims to investigate the lighting energy consumption in office buildings and the options for its reduction. One way to reduce lighting energy consumption is by improving the daylight design. A better use of daylight in buildings might be an outcome from the effort made in different directions. Like the improvement of a building's fabric and layout, the materials, even the furniture in a space influences the daylight quality considerably. Also very important role in lighting energy consumption has the development of more efficient lighting technology like the electric lighting control systems, such as photo sensors and occupancy sensors. Both systems are responsible so that the electric light is not used without reason. As the focusing area of this study, is to find ways to improve the daylight use in buildings, a consequent question is which are the methods provided in order to achieve this The accuracy of the methodology used is also an important issue in order to achieve reliable results. The methodology applied in this study includes the analysis of a case study by taking field measurements and computer simulations. The first stage included gathering information about the lighting design of the building and monitoring the light levels, both from natural and from the electric lighting. The second stage involved testing with computer simulations, different parameters that were expected to improve the daylight exploitation of the specific area. The results of the field measurements showed that the main problems of the space were the low natural light levels and the poor daylight distribution. The annual electric lighting energy consumption, as it was calculated with the use of computer simulations, represented the annual energy consumption of a typical air-conditioned prestige office building (energy consumption guide 19, for energy use in offices, 2000). After several computer simulations, the results showed that initial design parameters of the building can affect the lighting energy consumption of the space significantly. On the other hand, relatively small changes, like changing the reflectance of the surfaces and the lighting control systems can make even more difference to the light quality of the space and the reduction of lighting energy consumption.

Numerical simulation of the coaxial magneto-plasma accelerator and non-axisymmetric radio frequency discharge

NASA Astrophysics Data System (ADS)

Kuzenov, V. V.; Ryzhkov, S. V.; Frolko, P. A.

2017-05-01

The paper presents the results of mathematical modeling of physical processes in electronic devices such as helicon discharge and coaxial pulsed plasma thruster. A mathematical model of coaxial magneto-plasma accelerator (with a preionization helicon discharge), which allows estimating the transformation of one form of energy to another, as well as to evaluate the level of the contribution of different types of energy, the increase in mass of the accelerated plasmoid in the process of changing the speed. Main plasma parameters with experimental data were compared.

The statistical analysis of energy release in small-scale coronal structures

NASA Astrophysics Data System (ADS)

Ulyanov, Artyom; Kuzin, Sergey; Bogachev, Sergey

We present the results of statistical analysis of impulsive flare-like brightenings, which numerously occur in the quiet regions of solar corona. For our study, we utilized high-cadence observations performed with two EUV-telescopes - TESIS/Coronas-Photon and AIA/SDO. In total, we processed 6 sequences of images, registered throughout the period between 2009 and 2013, covering the rising phase of the 24th solar cycle. Based on high-speed DEM estimation method, we developed a new technique to evaluate the main parameters of detected events (geometrical sizes, duration, temperature and thermal energy). We then obtained the statistical distributions of these parameters and examined their variations depending on the level of solar activity. The results imply that near the minimum of the solar cycle the energy release in quiet corona is mainly provided by small-scale events (nanoflares), whereas larger events (microflares) prevail on the peak of activity. Furthermore, we investigated the coronal conditions that had specified the formation and triggering of registered flares. By means of photospheric magnetograms obtained with MDI/SoHO and HMI/SDO instruments, we examined the topology of local magnetic fields at different stages: the pre-flare phase, the peak of intensity and the ending phase. To do so, we introduced a number of topological parameters including the total magnetic flux, the distance between magnetic sources and their mutual arrangement. The found correlation between the change of these parameters and the formation of flares may offer an important tool for application of flare forecasting.

HelMod in the Works: From Direct Observations to the Local Interstellar Spectrum of Cosmic-Ray Electrons

NASA Astrophysics Data System (ADS)

Boschini, M. J.; Della Torre, S.; Gervasi, M.; Grandi, D.; Jóhannesson, G.; La Vacca, G.; Masi, N.; Moskalenko, I. V.; Pensotti, S.; Porter, T. A.; Quadrani, L.; Rancoita, P. G.; Rozza, D.; Tacconi, M.

2018-02-01

The local interstellar spectrum (LIS) of cosmic-ray (CR) electrons for the energy range 1 MeV to 1 TeV is derived using the most recent experimental results combined with the state-of-the-art models for CR propagation in the Galaxy and in the heliosphere. Two propagation packages, GALPROP and HELMOD, are combined to provide a single framework that is run to reproduce direct measurements of CR species at different modulation levels, and at both polarities of the solar magnetic field. An iterative maximum-likelihood method is developed that uses GALPROP-predicted LIS as input to HELMOD, which provides the modulated spectra for specific time periods of the selected experiments for model-data comparison. The optimized HelMod parameters are then used to adjust GALPROP parameters to predict a refined LIS with the procedure repeated subject to a convergence criterion. The parameter optimization uses an extensive data set of proton spectra from 1997 to 2015. The proposed CR electron LIS accommodates both the low-energy interstellar spectra measured by Voyager 1 as well as the high-energy observations by PAMELA and AMS-02 that are made deep in the heliosphere; it also accounts for Ulysses counting rate features measured out of the ecliptic plane. The interstellar and heliospheric propagation parameters derived in this study agree well with our earlier results for CR protons, helium nuclei, and anti-protons propagation and LIS obtained in the same framework.

String-inspired supergravity model at one loop

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

Gaillard, M.K.; Papadopoulos, A.; Pierce, D.M.

1992-03-15

We study a prototype supergravity model from superstrings, with three generations of matter fields in the untwisted sector, nonperturbatively induced supersymmetry breaking and including threshold corrections in conformity with modular invariance. The scale degeneracy of the vacuum is lifted at the one-loop level, allowing a determination of the fundamental parameters of the effective low-energy theory.

Approximate Approaches to the One-Dimensional Finite Potential Well

ERIC Educational Resources Information Center

Singh, Shilpi; Pathak, Praveen; Singh, Vijay A.

2011-01-01

The one-dimensional finite well is a textbook problem. We propose approximate approaches to obtain the energy levels of the well. The finite well is also encountered in semiconductor heterostructures where the carrier mass inside the well (m[subscript i]) is taken to be distinct from mass outside (m[subscript o]). A relevant parameter is the mass…

Understanding the magnetoelastic behavior of pure and Co substituted GdNi

NASA Astrophysics Data System (ADS)

Paudyal, Durga; Mudryk, Y.; Pecharsky, V. K.; Gschneidner, K. A., Jr.

Total-energy calculations employing local spin density approximation including Hubbard U (onsite electron correlation) parameter and temperature and magnetic field dependent x-ray diffraction experiments show large anisotropic shifts in lattice parameters and a giant linear magnetostriction without a structural transformation and a negligible volume magnetostriction in GdNi. In agreement with the magnetization and heat-capacity experiments, the total-energy and band splitting results confirm that the anisotropic shape changes in GdNi are associated with the second-order ferromagnetic to paramagnetic transformation. When the band splitting due to the ferromagnetic ordering of the 4 fmoments increases, the concomitant anisotropic changes in the lattice minimize the total free energy of the crystal indicating an unusual interplay between magnetism and crystal structure. The positive formation energy at 0K and the nature of the density of states at the Fermi level confirm an unstable equiatomic Gd compound when Ni is fully substituted by Co. However, the enhanced effective exchange interactions with small Co substitutions increase the Curie temperature without losing the chemical stability. The Ames Laboratory is operated for the US DOE by Iowa State. This work was supported by the DOE, Office of Basic Energy Sciences, Materials Sciences Division under Contract No. DE-AC02-07CH11358.

System for controlling a hybrid energy system

DOEpatents

Hoff, Brian D.; Akasam, Sivaprasad

2013-01-29

A method includes identifying a first operating sequence of a repeated operation of at least one non-traction load. The method also includes determining first and second parameters respectively indicative of a requested energy and output energy of the at least one non-traction load and comparing the determined first and second parameters at a plurality of time increments of the first operating sequence. The method also includes determining a third parameter of the hybrid energy system indicative of energy regenerated from the at least one non-traction load and monitoring the third parameter at the plurality of time increments of the first operating sequence. The method also includes determining at least one of an energy deficiency or an energy surplus associated with the non-traction load of the hybrid energy system and selectively adjusting energy stored within the storage device during at least a portion of a second operating sequence.

The "covariation method" for estimating the parameters of the standard Dynamic Energy Budget model II: Properties and preliminary patterns

NASA Astrophysics Data System (ADS)

Lika, Konstadia; Kearney, Michael R.; Kooijman, Sebastiaan A. L. M.

2011-11-01

The covariation method for estimating the parameters of the standard Dynamic Energy Budget (DEB) model provides a single-step method of accessing all the core DEB parameters from commonly available empirical data. In this study, we assess the robustness of this parameter estimation procedure and analyse the role of pseudo-data using elasticity coefficients. In particular, we compare the performance of Maximum Likelihood (ML) vs. Weighted Least Squares (WLS) approaches and find that the two approaches tend to converge in performance as the number of uni-variate data sets increases, but that WLS is more robust when data sets comprise single points (zero-variate data). The efficiency of the approach is shown to be high, and the prior parameter estimates (pseudo-data) have very little influence if the real data contain information about the parameter values. For instance, the effects of the pseudo-value for the allocation fraction κ is reduced when there is information for both growth and reproduction, that for the energy conductance is reduced when information on age at birth and puberty is given, and the effects of the pseudo-value for the maturity maintenance rate coefficient are insignificant. The estimation of some parameters (e.g., the zoom factor and the shape coefficient) requires little information, while that of others (e.g., maturity maintenance rate, puberty threshold and reproduction efficiency) require data at several food levels. The generality of the standard DEB model, in combination with the estimation of all of its parameters, allows comparison of species on the basis of parameter values. We discuss a number of preliminary patterns emerging from the present collection of parameter estimates across a wide variety of taxa. We make the observation that the estimated value of the fraction κ of mobilised reserve that is allocated to soma is far away from the value that maximises reproduction. We recognise this as the reason why two very different parameter sets must exist that fit most data set reasonably well, and give arguments why, in most cases, the set with the large value of κ should be preferred. The continued development of a parameter database through the estimation procedures described here will provide a strong basis for understanding evolutionary patterns in metabolic organisation across the diversity of life.

A Dynamic Energy Budget (DEB) model to describe Laternula elliptica (King, 1832) seasonal feeding and metabolism

PubMed Central

Ahn, In-Young; Guillaumot, Charlène; Danis, Bruno

2017-01-01

Antarctic marine organisms are adapted to an extreme environment, characterized by a very low but stable temperature and a strong seasonality in food availability arousing from variations in day length. Ocean organisms are particularly vulnerable to global climate change with some regions being impacted by temperature increase and changes in primary production. Climate change also affects the biotic components of marine ecosystems and has an impact on the distribution and seasonal physiology of Antarctic marine organisms. Knowledge on the impact of climate change in key species is highly important because their performance affects ecosystem functioning. To predict the effects of climate change on marine ecosystems, a holistic understanding of the life history and physiology of Antarctic key species is urgently needed. DEB (Dynamic Energy Budget) theory captures the metabolic processes of an organism through its entire life cycle as a function of temperature and food availability. The DEB model is a tool that can be used to model lifetime feeding, growth, reproduction, and their responses to changes in biotic and abiotic conditions. In this study, we estimate the DEB model parameters for the bivalve Laternula elliptica using literature-extracted and field data. The DEB model we present here aims at better understanding the biology of L. elliptica and its levels of adaptation to its habitat with a special focus on food seasonality. The model parameters describe a metabolism specifically adapted to low temperatures, with a low maintenance cost and a high capacity to uptake and mobilise energy, providing this organism with a level of energetic performance matching that of related species from temperate regions. It was also found that L. elliptica has a large energy reserve that allows enduring long periods of starvation. Additionally, we applied DEB parameters to time-series data on biological traits (organism condition, gonad growth) to describe the effect of a varying environment in food and temperature on the organism condition and energy use. The DEB model developed here for L. elliptica allowed us to improve benchmark knowledge on the ecophysiology of this key species, providing new insights in the role of food availability and temperature on its life cycle and reproduction strategy. PMID:28850607

A Dynamic Energy Budget (DEB) model to describe Laternula elliptica (King, 1832) seasonal feeding and metabolism.

PubMed

Agüera, Antonio; Ahn, In-Young; Guillaumot, Charlène; Danis, Bruno

2017-01-01

Antarctic marine organisms are adapted to an extreme environment, characterized by a very low but stable temperature and a strong seasonality in food availability arousing from variations in day length. Ocean organisms are particularly vulnerable to global climate change with some regions being impacted by temperature increase and changes in primary production. Climate change also affects the biotic components of marine ecosystems and has an impact on the distribution and seasonal physiology of Antarctic marine organisms. Knowledge on the impact of climate change in key species is highly important because their performance affects ecosystem functioning. To predict the effects of climate change on marine ecosystems, a holistic understanding of the life history and physiology of Antarctic key species is urgently needed. DEB (Dynamic Energy Budget) theory captures the metabolic processes of an organism through its entire life cycle as a function of temperature and food availability. The DEB model is a tool that can be used to model lifetime feeding, growth, reproduction, and their responses to changes in biotic and abiotic conditions. In this study, we estimate the DEB model parameters for the bivalve Laternula elliptica using literature-extracted and field data. The DEB model we present here aims at better understanding the biology of L. elliptica and its levels of adaptation to its habitat with a special focus on food seasonality. The model parameters describe a metabolism specifically adapted to low temperatures, with a low maintenance cost and a high capacity to uptake and mobilise energy, providing this organism with a level of energetic performance matching that of related species from temperate regions. It was also found that L. elliptica has a large energy reserve that allows enduring long periods of starvation. Additionally, we applied DEB parameters to time-series data on biological traits (organism condition, gonad growth) to describe the effect of a varying environment in food and temperature on the organism condition and energy use. The DEB model developed here for L. elliptica allowed us to improve benchmark knowledge on the ecophysiology of this key species, providing new insights in the role of food availability and temperature on its life cycle and reproduction strategy.

BOREAS Level-0 ER-2 Daedalus TMS Imagery Digital Counts in BIL Format

NASA Technical Reports Server (NTRS)

Newcomer, Jeffrey A.; Dominguez, Roseanne; Hall, Forrest G. (Editor)

2000-01-01

The level-0 Daedalus Thematic Mapper Simulator (TMS) imagery, along with the other remotely sensed images, was collected to provide spatially extensive information about radiant energy over the primary BOReal Ecosystem-Atmosphere Study (BOREAS) study areas. This information includes detailed land cover and biophysical parameter maps such as fraction of Photosynthetically Active Radiation (fPAR) and Leaf Area Index (LAI). Two flights of the Daedalus TMS instrument were made onboard the ER-2 aircraft on 16-Sep-1994 and 17-Sep-1994.

CW-cavity ring down spectroscopy of the ozone molecule in the 6220-6400 cm -1 region

NASA Astrophysics Data System (ADS)

Barbe, A.; De Backer-Barilly, M.-R.; Tyuterev, Vl. G.; Kassi, S.; Campargue, A.

2007-11-01

The absorption spectrum of ozone, 16O 3, has been recorded in the 6220-6400 cm -1 region by high sensitivity CW-cavity ring down spectroscopy ( αmin ˜ 3 × 10 -10 cm -1). 1836 rovibrational transitions have been assigned to the 2 ν2 + 5 ν3, 5 ν1 + ν3 and 2 ν1 + 2 ν2 + 3 ν3 A-type bands centred at 6305, 6355 and 6387 cm -1, respectively. In addition, 99 lines of the very weak ν1 + 2 ν2 + 4 ν3 and 4 ν1 + 3 ν2 B-type bands are identified. The modeling of the observed spectrum in the effective Hamiltonian approach was particularly laborious and complex as several rovibrational interactions of both Coriolis and anaharmonic type were found to be of importance, in particular for the (124) vibrational state. Nevertheless, it has finally been possible to fit the 990 experimentally determined energy levels with an rms deviation of 8.29 × 10 -3 cm -1 and to derive the transition moment parameters allowing a satisfactory reproduction of the observed intensities. As the differences in positions between the final calculations and observations are still larger than the experimental accuracy, we provide the list of all energy levels derived from the observation, in addition to their differences with the calculated ones. These experimental energy levels, with the transition moment parameters were used to generate a line-list of 2451 transitions, reproducing the observed spectrum. This list is given as Supplementary Material.

Alterations of energy metabolism and glutathione levels of HL-60 cells induced by methacrylates present in composite resins.

PubMed

Nocca, G; De Palma, F; Minucci, A; De Sole, P; Martorana, G E; Callà, C; Morlacchi, C; Gozzo, M L; Gambarini, G; Chimenti, C; Giardina, B; Lupi, A

2007-03-01

Methacrylic compounds such as 2-hydroxyethyl methacrylate (HEMA), triethylene glycol dimethacrylate (TEGDMA) and bisphenol A glycerolate (1 glycerol/phenol) dimethacrylate (Bis-GMA) are largely present in auto- or photopolymerizable composite resins. Since the polymerization reaction is never complete, these molecules are released into the oral cavity tissues and biological fluids where they could cause local adverse effects. The aim of this work was to verify the hypothesis that the biological effects of HEMA, TEGDMA and Bis-GMA - at a non-cytotoxic concentration - depend on the interaction with mitochondria and exert consequent alterations of energy metabolism, GSH levels and the related pathways in human promyelocytic cell line (HL-60). The biological effects of methacrylic monomers were determined by analyzing the following parameters: GSH concentration, glucose-6-phosphate dehydrogenase (G6PDH) and glutathione reductase (GR) activity, oxygen and glucose consumption and lactate production along with cell differentiation and proliferation. All monomers induced both cellular differentiation and decrease in oxygen consumption. Cells treated with TEGDMA and Bis-GMA showed a significant enhancement of glucose consumption and lactate production. TEGDMA and HEMA induced GSH depletion stimulating G6PDH and GR activity. All the monomers under study affect the metabolism of HL-60 cells and show differentiating activity. Since alterations in cellular metabolism occurred at compound concentrations well below cytotoxic levels, the changes in energy metabolism and glutathione redox balance could be considered as potential mechanisms for inducing clinical and sub-clinical adverse effects and thus providing useful parameters when testing biocompatibility of dental materials.

The Effectiveness of Taiwan Building Energy Regulation under the influence of Future Climate

NASA Astrophysics Data System (ADS)

Weng, Yu-Teng; Huang, Kuo-Tsang

2017-04-01

Building energy consumption comprises circa 40% of the national annual energy usage in Taiwan, and the majority proportion is attributed to the cooling apparatus usage. As cooling energy is closely related to the outdoor climate, it is expected that the future global climate change would amplify its demand. Considering the building energy regulation criteria are the minimum requirements that the building has to be complied with, this study tried to investigate whether the current building energy regulation in Taiwan, initiated in 2013, would still be capable of maintaining the energy use in the future as today's level. The research adopted EnergyPlus to simulate the annual cooling energy use of several virtual office building cases with the constructed hourly future weather data under future climate change scenarios of RCP45 and RCP85 defined by IPCC. The virtual building cases are generated by a structured orthogonal array with each case is constituted by 10 building design parameters. The results revealed that the building energy consumption based on the current regulation criteria failed to maintain at the same level in the future as oppose to nowadays. By comparing to the current cooling energy usage, it would rise by 13% and 22% in RCP45 and RCP85, respectively, at the end of this century. This research further parametrically studied the potential cooling energy mitigation strategies and proposed effective building envelope design schemes in order to neutralize the future building energy increase.

Analysis of activation energy in Couette-Poiseuille flow of nanofluid in the presence of chemical reaction and convective boundary conditions

NASA Astrophysics Data System (ADS)

Zeeshan, A.; Shehzad, N.; Ellahi, R.

2018-03-01

The motivation of the current article is to explore the energy activation in MHD radiative Couette-Poiseuille flow nanofluid in horizontal channel with convective boundary conditions. The mathematical model of Buongiorno [1] effectively describes the current flow analysis. Additionally, the impact of chemical reaction is also taken in account. The governing flow equations are simplified with the help of boundary layer approximations. Non-linear coupled equations for momentum, energy and mass transfer are tackled with analytical (HAM) technique. The influence of dimensionless convergence parameter like Brownian motion parameter, radiation parameter, buoyancy ratio parameter, dimensionless activation energy, thermophoresis parameter, temperature difference parameter, dimensionless reaction rate, Schmidt number, Brinkman number, Biot number and convection diffusion parameter on velocity, temperature and concentration profiles are discussed graphically and in tabular form. From the results, it is elaborate that the nanoparticle concentration is directly proportional to the chemical reaction with activation energy and the performance of Brownian motion on nanoparticle concentration gives reverse pattern to that of thermophoresis parameter.

The Renner-Teller effect in HCCCl(+)(X̃(2)Π) studied by zero-kinetic energy photoelectron spectroscopy and ab initio calculations.

PubMed

Sun, Wei; Dai, Zuyang; Wang, Jia; Mo, Yuxiang

2015-05-21

The spin-vibronic energy levels of the chloroacetylene cation up to 4000 cm(-1) above the ground state have been measured using the one-photon zero-kinetic energy photoelectron spectroscopic method. The spin-vibronic energy levels have also been calculated using a diabatic model, in which the potential energy surfaces are expressed by expansions of internal coordinates, and the Hamiltonian matrix equation is solved using a variational method with harmonic basis functions. The calculated spin-vibronic energy levels are in good agreement with the experimental data. The Renner-Teller (RT) parameters describing the vibronic coupling for the H-C≡C bending mode (ε4), Cl-C≡C bending mode (ε5), the cross-mode vibronic coupling (ε45) of the two bending vibrations, and their vibrational frequencies (ω4 and ω5) have also been determined using an effective Hamiltonian matrix treatment. In comparison with the spin-orbit interaction, the RT effect in the H-C≡C bending (ε4) mode is strong, while the RT effect in the Cl-C≡C bending mode is weak. There is a strong cross-mode vibronic coupling of the two bending vibrations, which may be due to a vibronic resonance between the two bending vibrations. The spin-orbit energy splitting of the ground state has been determined for the first time and is found to be 209 ± 2 cm(-1).

Three-state combinatorial switch models as applied to the binding of oxygen by human hemoglobin.

PubMed

Straume, M; Johnson, M L

1988-02-23

We have generated a series of all 6561 unique, discrete three-state combinatorial switch models to describe the partitioning of the cooperative oxygen-binding free change among the 10 variously ligated forms of human hemoglobin tetramers. These models were inspired by the experimental observation of Smith and Ackers that the cooperative free energy of the intersubunit contact regions of the 10 possible ligated forms of human hemoglobin tetramers can be represented by a particular distribution of three distinct energy levels [Smith, F. R., & Ackers, G. K. (1985) Proc. Natl. Acad. Sci. U.S.A. 82, 5347-5351]. A statistical thermodynamic formulation accounting for both dimer-tetramer equilibria and ligand binding properties of hemoglobin solutions as a function of oxygen and protein concentrations was utilized to exhaustively test these thermodynamic models. In this series of models each of the 10 ligated forms of the hemoglobin tetramer can exist in one, and only one, of three possible energy levels; i.e., each ligated form was assumed to be associated with a discrete energy state. This series of models includes all possible ways that the 10 ligation states of hemoglobin can be distributed into three distinct cooperative energy levels. The mathematical models, as presented here, do not permit equilibria between energy states to exist for any of the 10 unique ligated forms of hemoglobin tetramers. These models were analyzed by nonlinear least-squares estimation of the free energy parameters characteristic of this statistical thermodynamic development.(ABSTRACT TRUNCATED AT 250 WORDS)

Vibrational spectroscopy (FT-IR and Laser-Raman) investigation, and computational (M06-2X and B3LYP) analysis on the structure of 4-(3-fluorophenyl)-1-(propan-2-ylidene)-thiosemicarbazone.

PubMed

Sert, Yusuf; Miroslaw, Barbara; Çırak, Çağrı; Doğan, Hatice; Szulczyk, Daniel; Struga, Marta

2014-07-15

In this study, the experimental and theoretical vibrational spectral analysis of 4-(3-fluorophenyl)-1-(propan-2-ylidene)-thiosemicarbazone have been carried out. The experimental FT-IR (4000-400 cm(-1)) and Laser-Raman spectra (4000-100 cm(-1)) have been recorded for the solid state samples. The theoretical vibrational frequencies and the optimized geometric parameters (bond lengths and angles) have been calculated for gas phase using density functional theory (DFT/B3LYP: Becke, 3-parameter, Lee-Yang-Parr) and M06-2X (the highly parametrized, empirical exchange correlation function) quantum chemical methods with 6-311++G(d,p) basis set. The diversity in molecular geometry of fluorophenyl substituted thiosemicarbazones has been discussed based on the X-ray crystal structure reports and theoretical calculation results from the literature. The assignments of the vibrational frequencies have been done on the basis of potential energy distribution (PED) analysis by using VEDA4 software. A good correlation was found between the computed and experimental geometric and vibrational data. In addition, the highest occupied (HOMO) and lowest unoccupied (LUMO) molecular orbital energy levels and other related molecular energy values of the compound have been determined using the same level of theoretical calculations. Copyright © 2014 Elsevier B.V. All rights reserved.

The influence of dentin demineralization on morphological features of cavities using Er:YAG laser.

PubMed

Melo, Mary A S; Lima, Juliana P M; Passos, Vanara F; Rodrigues, Lidiany K A

2015-01-01

The purpose of this study was to evaluate the influence of erbium-doped: yttrium-aluminum-garnet (Er:YAG) laser parameters and different degrees of demineralization on morphological features, diameter, and depth of prepared cavities. Minimally invasive dentin caries removal has been recommended. Ablation of deep caries lesions using Er:YAG laser should preserve remaining demineralized dentin; however, the influence of the degree of mineralization of this substrate had not been entirely described. A randomized, factorial design was used to study the effects of two factors. Laser parameter was tested at two levels (250 mJ/4 Hz vs. 200 mJ/2 Hz) and degree of demineralization was tested at four levels (control, two-four-eight cycles). Twelve slabs of human dentin were divided into four groups according to the number of cycles induced by pH-cycling: G1, zero cycles; G2, two cycles, G3, four cycles, and G4, eight cycles. An Er:YAG laser was used at an output energy of 250 mJ/4 Hz and 200 mJ/2 Hz for all groups, for 10 sec at 12 mm distance focus/object. Circumference and depth of the cavities were measured on scanning electron microscopy (SEM) images using image analysis software. The mean values were subjected to two way analysis of variance (ANOVA) and Tukey tests. When using 250 mJ/4 Hz, the mean values of circumferential area increased significantly in relation to control (503.54 μm(2)) with increasing demineralization level (eight cycles) (555.45 μm(2)). Regardless of the demineralization level, there was also significant statistical difference in the studied measurements of the cavities when 250 mJ/4 Hz and 200 mJ/2 Hz were used. SEM also showed that laser cavity preparations left no smear layer, and the dentinal tubules were clear. The circumferential area and depth measurements were affected by laser parameter and demineralization level (eight cycles). Energy level output represents a relevant factor for increased circumferential area and depth measurements. High demineralized artificially caries-affected dentin may also imply higher ablation. Appropriated parameter of laser pulse frequency/power density for demineralized dentin should be used for effective less-invasive caries treatment.

Indoor radon problem in energy efficient multi-storey buildings.

PubMed

Yarmoshenko, I V; Vasilyev, A V; Onishchenko, A D; Kiselev, S M; Zhukovsky, M V

2014-07-01

Modern energy-efficient architectural solutions and building construction technologies such as monolithic concrete structures in combination with effective insulation reduce air permeability of building envelope. As a result, air exchange rate is significantly reduced and conditions for increased radon accumulation in indoor air are created. Based on radon survey in Ekaterinburg, Russia, remarkable increase in indoor radon concentration level in energy-efficient multi-storey buildings was found in comparison with similar buildings constructed before the-energy-saving era. To investigate the problem of indoor radon in energy-efficient multi-storey buildings, the measurements of radon concentration have been performed in seven modern buildings using radon monitoring method. Values of air exchange rate and other parameters of indoor climate in energy-efficient buildings have been estimated. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Crops Models for Varying Environmental Conditions

NASA Technical Reports Server (NTRS)

Jones, Harry; Cavazzoni, James; Keas, Paul

2001-01-01

New variable environment Modified Energy Cascade (MEC) crop models were developed for all the Advanced Life Support (ALS) candidate crops and implemented in SIMULINK. The MEC models are based on the Volk, Bugbee, and Wheeler Energy Cascade (EC) model and are derived from more recent Top-Level Energy Cascade (TLEC) models. The MEC models simulate crop plant responses to day-to-day changes in photosynthetic photon flux, photoperiod, carbon dioxide level, temperature, and relative humidity. The original EC model allows changes in light energy but uses a less accurate linear approximation. The simulation outputs of the new MEC models for constant nominal environmental conditions are very similar to those of earlier EC models that use parameters produced by the TLEC models. There are a few differences. The new MEC models allow setting the time for seed emergence, have realistic exponential canopy growth, and have corrected harvest dates for potato and tomato. The new MEC models indicate that the maximum edible biomass per meter squared per day is produced at the maximum allowed carbon dioxide level, the nominal temperatures, and the maximum light input. Reducing the carbon dioxide level from the maximum to the minimum allowed in the model reduces crop production significantly. Increasing temperature decreases production more than it decreases the time to harvest, so productivity in edible biomass per meter squared per day is greater at nominal than maximum temperatures, The productivity in edible biomass per meter squared per day is greatest at the maximum light energy input allowed in the model, but the edible biomass produced per light energy input unit is lower than at nominal light levels. Reducing light levels increases light and power use efficiency. The MEC models suggest we can adjust the light energy day-to- day to accommodate power shortages or Lise excess power while monitoring and controlling edible biomass production.

CHARMM Drude Polarizable Force Field for Aldopentofuranoses and Methyl-aldopentofuranosides

PubMed Central

Jana, Madhurima; MacKerell, Alexander D.

2015-01-01

An empirical all-atom CHARMM polarizable force filed for aldopentofuranoses and methyl-aldopentofuranosides based on the classical Drude oscillator is presented. A single electrostatic model is developed for eight different diastereoisomers of aldopentofuranoses by optimizing the existing electrostatic and bonded parameters as transferred from ethers, alcohols and hexopyranoses to reproduce quantum mechanical (QM) dipole moments, furanose-water interaction energies and conformational energies. Optimization of selected electrostatic and dihedral parameters was performed to generate a model for methyl-aldopentofuranosides. Accuracy of the model was tested by reproducing experimental data for crystal intramolecular geometries and lattice unit cell parameters, aqueous phase densities, and ring pucker and exocyclic rotamer populations as obtained from NMR experiments. In most cases the model is found to reproduce both QM data and experimental observables in an excellent manner, while for the remainder the level of agreement is in the satisfactory regimen. In aqueous phase simulations the monosaccharides have significantly enhanced dipoles as compared to the gas phase. The final model from this study is transferrable for future studies on carbohydrates and can be used with the existing CHARMM Drude polarizable force field for biomolecules. PMID:26018564

Eigensolutions, Shannon entropy and information energy for modified Tietz-Hua potential

NASA Astrophysics Data System (ADS)

Onate, C. A.; Onyeaju, M. C.; Ituen, E. E.; Ikot, A. N.; Ebomwonyi, O.; Okoro, J. O.; Dopamu, K. O.

2018-04-01

The Tietz-Hua potential is modified by the inclusion of De ( {{Ch - 1}/{1 - C_{h e^{{ - bh ( {r - re } )}} }}} )be^{{ - bh ( {r - re } )}} term to the Tietz-Hua potential model since a potential of such type is very good in the description and vibrational energy levels for diatomic molecules. The energy eigenvalues and the corresponding eigenfunctions are explicitly obtained using the methodology of parametric Nikiforov-Uvarov. By putting the potential parameter b = 0, in the modified Tietz-Hua potential quickly reduces to the Tietz-Hua potential. To show more applications of our work, we have computed the Shannon entropy and Information energy under the modified Tietz-Hua potential. However, the computation of the Shannon entropy and Information energy is an extension of the work of Falaye et al., who computed only the Fisher information under Tietz-Hua potential.

Hydrogenic impurity bound polaron in an anisotropic quantum dot

NASA Astrophysics Data System (ADS)

Chen, Shi-Hua

2018-01-01

The effect of the electron-phonon interaction on an electron bound to a hydrogenic impurity in a three-dimensional (3D) anisotropic quantum dot (QD) is studied theoretically. We use the Landau-Pekar variational approach to calculate the binding energy of ground state (GS) and first-excited state (ES) with considering electron-phonon interaction. The expressions of the GS and ES energies under investigation depict a rich variety of dependent relationship with the variational parameters in three different limiting cases. Numerical calculations were performed for ZnSe QDs with different confinement lengths in the xy-plane and the z-direction, respectively. It is illustrated that binding energies of impurity polarons corresponding to each level are larger in small QDs. Furthermore, the contribution to binding energy from phonon is about 15% of the total binding energy.

Distributed activation energy model parameters of some Turkish coals

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

Gunes, M.; Gunes, S.K.

2008-07-01

A multi-reaction model based on distributed activation energy has been applied to some Turkish coals. The kinetic parameters of distributed activation energy model were calculated via computer program developed for this purpose. It was observed that the values of mean of activation energy distribution vary between 218 and 248 kJ/mol, and the values of standard deviation of activation energy distribution vary between 32 and 70 kJ/mol. The correlations between kinetic parameters of the distributed activation energy model and certain properties of coal have been investigated.

EPR, optical and superposition model study of Mn2+ doped L+ glutamic acid

NASA Astrophysics Data System (ADS)

Kripal, Ram; Singh, Manju

2015-12-01

Electron paramagnetic resonance (EPR) study of Mn2+ doped L+ glutamic acid single crystal is done at room temperature. Four interstitial sites are observed and the spin Hamiltonian parameters are calculated with the help of large number of resonant lines for various angular positions of external magnetic field. The optical absorption study is also done at room temperature. The energy values for different orbital levels are calculated, and observed bands are assigned as transitions from 6A1g(s) ground state to various excited states. With the help of these assigned bands, Racah inter-electronic repulsion parameters B = 869 cm-1, C = 2080 cm-1 and cubic crystal field splitting parameter Dq = 730 cm-1 are calculated. Zero field splitting (ZFS) parameters D and E are calculated by the perturbation formulae and crystal field parameters obtained using superposition model. The calculated values of ZFS parameters are in good agreement with the experimental values obtained by EPR.

Design of multi-energy Helds coupling testing system of vertical axis wind power system

NASA Astrophysics Data System (ADS)

Chen, Q.; Yang, Z. X.; Li, G. S.; Song, L.; Ma, C.

2016-08-01

The conversion efficiency of wind energy is the focus of researches and concerns as one of the renewable energy. The present methods of enhancing the conversion efficiency are mostly improving the wind rotor structure, optimizing the generator parameters and energy storage controller and so on. Because the conversion process involves in energy conversion of multi-energy fields such as wind energy, mechanical energy and electrical energy, the coupling effect between them will influence the overall conversion efficiency. In this paper, using system integration analysis technology, a testing system based on multi-energy field coupling (MEFC) of vertical axis wind power system is proposed. When the maximum efficiency of wind rotor is satisfied, it can match to the generator function parameters according to the output performance of wind rotor. The voltage controller can transform the unstable electric power to the battery on the basis of optimizing the parameters such as charging times, charging voltage. Through the communication connection and regulation of the upper computer system (UCS), it can make the coupling parameters configure to an optimal state, and it improves the overall conversion efficiency. This method can test the whole wind turbine (WT) performance systematically and evaluate the design parameters effectively. It not only provides a testing method for system structure design and parameter optimization of wind rotor, generator and voltage controller, but also provides a new testing method for the whole performance optimization of vertical axis wind energy conversion system (WECS).

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

Krishnan, Venkat; Cole, Wesley

Power sector capacity expansion models (CEMs) have a broad range of spatial resolutions. This paper uses the Regional Energy Deployment System (ReEDS) model, a long-term national scale electric sector CEM, to evaluate the value of high spatial resolution for CEMs. ReEDS models the United States with 134 load balancing areas (BAs) and captures the variability in existing generation parameters, future technology costs, performance, and resource availability using very high spatial resolution data, especially for wind and solar modeled at 356 resource regions. In this paper we perform planning studies at three different spatial resolutions--native resolution (134 BAs), state-level, and NERCmore » region level--and evaluate how results change under different levels of spatial aggregation in terms of renewable capacity deployment and location, associated transmission builds, and system costs. The results are used to ascertain the value of high geographically resolved models in terms of their impact on relative competitiveness among renewable energy resources.« less

Resonant tunneling through discrete quantum states in stacked atomic-layered MoS2.

PubMed

Nguyen, Linh-Nam; Lan, Yann-Wen; Chen, Jyun-Hong; Chang, Tay-Rong; Zhong, Yuan-Liang; Jeng, Horng-Tay; Li, Lain-Jong; Chen, Chii-Dong

2014-05-14

Two-dimensional crystals can be assembled into three-dimensional stacks with atomic layer precision, which have already shown plenty of fascinating physical phenomena and been used for prototype vertical-field-effect-transistors.1,2 In this work, interlayer electron tunneling in stacked high-quality crystalline MoS2 films were investigated. A trilayered MoS2 film was sandwiched between top and bottom electrodes with an adjacent bottom gate, and the discrete energy levels in each layer could be tuned by bias and gate voltages. When the discrete energy levels aligned, a resonant tunneling peak appeared in the current-voltage characteristics. The peak position shifts linearly with perpendicular magnetic field, indicating formation of Landau levels. From this linear dependence, the effective mass and Fermi velocity are determined and are confirmed by electronic structure calculations. These fundamental parameters are useful for exploitation of its unique properties.

Quantum gravitational collapse as a Dirac particle on the half line

NASA Astrophysics Data System (ADS)

Hassan, Syed Moeez; Husain, Viqar; Ziprick, Jonathan

2018-05-01

We show that the quantum dynamics of a thin spherical shell in general relativity is equivalent to the Coulomb-Dirac equation on the half line. The Hamiltonian has a one-parameter family of self-adjoint extensions with a discrete energy spectrum |E |m , where m is the rest mass of the shell and E is the Arnowitt-Deser-Misner mass. For sufficiently large m , the ground state energy level is negative. This suggests that classical positivity of energy does not survive quantization. The scattering states provide a realization of singularity avoidance. We speculate on the consequences of these results for black hole radiation.

Luminescence of BaBrI and SrBrI single crystals doped with Eu2+

NASA Astrophysics Data System (ADS)

Shalaev, A. A.; Shendrik, R.; Myasnikova, A. S.; Bogdanov, A.; Rusakov, A.; Vasilkovskyi, A.

2018-05-01

The crystal growth procedure and luminescence properties of pure and Eu2+-doped BaBrI and SrBrI crystals are reported. Emission and excitation spectra were recorded under ultraviolet and vacuum ultraviolet excitations. The energy of the first Eu2+ 4f-5d transition and SrBrI band gap are obtained. The electronic structure calculations were performed within GW approximation as implemented in the Vienna Ab Initio Simulation Package. The energy between lowest Eu2+ 5d state and the bottom of conduction band are found based on luminescence quenching parameters. The vacuum referred binding energy diagram of lanthanide levels was constructed using the chemical shift model.

The cosmological dark sector as a scalar σ -meson field

NASA Astrophysics Data System (ADS)

Carneiro, Saulo

2018-03-01

Previous quantum field estimations of the QCD vacuum in the expanding space-time lead to a dark energy component scaling linearly with the Hubble parameter, which gives the correct figure for the observed cosmological term. Here we show that this behaviour also appears at the classical level, as a result of the chiral symmetry breaking in a low energy, effective σ -model. The dark sector is described in a unified way by the σ condensate and its fluctuations, giving rise to a decaying dark energy and a homogeneous creation of non-relativistic dark particles. The creation rate and the future asymptotic de Sitter horizon are both determined by the σ mass scale.

Can the KTP laser change the cementum surface of healthy and diseased teeth providing an acceptable root surface for fibroblast attachment?

NASA Astrophysics Data System (ADS)

Mailhot, Jason M.; Garnick, Jerry J.

1996-04-01

The purpose of our research is to determine the effects of KTP laser on root cementum and fibroblast attachment. Initial work has been completed in testing the effect of different energy levels on root surfaces. From these studies optimal energy levels were determined. In subsequent studies the working distance and exposure time required to obtain significant fibroblast attachment to healthy cementum surfaces were investigated. Results showed that lased cemental surfaces exhibited changes in surface topography which ranged from a melted surface to an apparent slight fusion of the surface of the covering smear layer. When the optimal energy level was used, fibroblasts demonstrate attachment on the specimens, resulting in the presence of a monolayer of cells on the control surfaces as well as on the surfaces lased with this energy level. The present study investigates the treatment of pathological root surfaces and calculus with a KTP laser utilizing these optimal parameters determine previously. Thirty single rooted teeth with advanced periodontal disease and ten healthy teeth were obtained, crowns were sectioned and roots split longitudinally. Forty test specimens were assigned into 1 of 4 groups; pathologic root--not lased, pathologic root--lased, root planed root and health root planed root. Human gingival fibroblasts were seeded on specimens and cultured for 24 hours. Specimens were processed for SEM. The findings suggest that with the KTP laser using a predetermined energy level applied to pathological root surfaces, the lased surfaces provided an unacceptable surface for fibroblast attachment. However, the procedural control using healthy root planed surfaces did demonstrate fibroblast attachment.

Global Nonlinear Analysis of Piezoelectric Energy Harvesting from Ambient and Aeroelastic Vibrations

NASA Astrophysics Data System (ADS)

Abdelkefi, Abdessattar

Converting vibrations to a usable form of energy has been the topic of many recent investigations. The ultimate goal is to convert ambient or aeroelastic vibrations to operate low-power consumption devices, such as microelectromechanical systems, heath monitoring sensors, wireless sensors or replacing small batteries that have a finite life span or would require hard and expensive maintenance. The transduction mechanisms used for transforming vibrations to electric power include: electromagnetic, electrostatic, and piezoelectric mechanisms. Because it can be used to harvest energy over a wide range of frequencies and because of its ease of application, the piezoelectric option has attracted significant interest. In this work, we investigate the performance of different types of piezoelectric energy harvesters. The objective is to design and enhance the performance of these harvesters. To this end, distributed-parameter and phenomenological models of these harvesters are developed. Global analysis of these models is then performed using modern methods of nonlinear dynamics. In the first part of this Dissertation, global nonlinear distributed-parameter models for piezoelectric energy harvesters under direct and parametric excitations are developed. The method of multiple scales is then used to derive nonlinear forms of the governing equations and associated boundary conditions, which are used to evaluate their performance and determine the effects of the nonlinear piezoelectric coefficients on their behavior in terms of softening or hardening. In the second part, we assess the influence of the linear and nonlinear parameters on the dynamic behavior of a wing-based piezoaeroelastic energy harvester. The system is composed of a rigid airfoil that is constrained to pitch and plunge and supported by linear and nonlinear torsional and flexural springs with a piezoelectric coupling attached to the plunge degree of freedom. Linear analysis is performed to determine the effects of the linear spring coefficients and electrical load resistance on the flutter speed. Then, the normal form of the Hopf bifurcation ( utter) is derived to characterize the type of instability and determine the effects of the aerodynamic nonlinearities and the nonlinear coefficients of the springs on the system's stability near the bifurcation. This is useful to characterize the effects of different parameters on the system's output and ensure that subcritical or "catastrophic" bifurcation does not take place. Both linear and nonlinear analyses are then used to design and enhance the performance of these harvesters. In the last part, the concept of energy harvesting from vortex-induced vibrations of a circular cylinder is investigated. The power levels that can be generated from these vibrations and the variations of these levels with the freestream velocity are determined. A mathematical model that accounts for the coupled lift force, cylinder motion and generated voltage is presented. Linear analysis of the electromechanical model is performed to determine the effects of the electrical load resistance on the natural frequency of the rigid cylinder and the onset of the synchronization region. The impacts of the nonlinearities on the cylinder's response and energy harvesting are then investigated.

Structural and electronic parameters of ferroelectric KWOF

NASA Astrophysics Data System (ADS)

Atuchin, V. V.; Gavrilova, T. A.; Kesler, V. G.; Molokeev, M. S.; Aleksandrov, K. S.

2010-11-01

The low-temperature ferroelectric G2 polymorph of K 3WO 3F 3 oxyfluoride is formed by chemical synthesis. The electronic parameters of G2-K 3WO 3F 3 have been measured by X-ray photoelectron spectroscopy under excitation with Al Kα radiation (1486.6 eV). Detailed spectra have been recorded for all element core levels and Auger lines. The chemical bonding effects in the WO 3F 3 and WO 6 octahedrons are considered by using the binding energy difference ΔBE(O-W)=BE(O 1s)-BE(W 4f).

Landau quantization in the spinning cosmic string spacetime

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

Muniz, C.R., E-mail: celiomuniz@yahoo.com; Bezerra, V.B.; Cunha, M.S.

2014-11-15

We analyze the quantum phenomenon arising from the interaction of a spinless charged particle with a rotating cosmic string, under the action of a static and uniform magnetic field parallel to the string. We calculate the energy levels of the particle in the non-relativistic approach, showing how these energies depend on the parameters involved in the problem. In order to do this, we solve the time independent Schrödinger equation in the geometry of the spinning cosmic string, taking into account that the coupling between the rotation of the spacetime and the angular momentum of the particle is very weak, suchmore » that makes sense to apply the Schrödinger equation in a curved background whose metric has an off diagonal term which involves time and space. It is also assumed that the particle orbits sufficiently far from the boundary of the region of closed timelike curves which exist around this topological defect. Finally, we find the Landau levels of the particle in the presence of a spinning cosmic string endowed with internal structure, i.e., having a finite width and uniformly filled with both material and vacuum energies. - Highlights: • Solution of the wave equation characterizing the problem. • Energy levels of the particle in spacetime of the structureless string. • Expression for an analogous of the quadratic Zeeman effect. • Energy levels of the particle in spacetime of the string with internal structure. • Evidence of the string structure by the internal existence of the vacuum energy.« less

Economical and environmental analysis of thermal and photovoltaic solar energy as source of heat for industrial processes

NASA Astrophysics Data System (ADS)

Pérez-Aparicio, Elena; Lillo-Bravo, Isidoro; Moreno-Tejera, Sara; Silva-Pérez, Manuel

2017-06-01

Thermal energy for industrial processes can be generated using thermal (ST) or photovoltaic (PV) solar energy. ST energy has traditionally been the most favorable option due to its cost and efficiency. Current costs and efficiencies values make the PV solar energy become an alternative to ST energy as supplier of industrial process heat. The aim of this study is to provide a useful tool to decide in each case which option is economically and environmentally the most suitable alternative. The methodology used to compare ST and PV systems is based on the calculation of the levelized cost of energy (LCOE) and greenhouse gas emissions (GHG) avoided by using renewable technologies instead of conventional sources of energy. In both cases, these calculations depend on costs and efficiencies associated with ST or PV systems and the conversion factor from thermal or electrical energy to GHG. To make these calculations, a series of hypotheses are assumed related to consumer and energy prices, operation, maintenance and replacement costs, lifetime of the system or working temperature of the industrial process. This study applies the methodology at five different sites which have been selected taking into account their radiometric and meteorological characteristics. In the case of ST energy three technologies are taken into account, compound parabolic concentrator (CPC), linear Fresnel collector (LFC) and parabolic trough collector (PTC). The PV option includes two ways of use of generated electricity, an electrical resistance or a combination of an electrical resistance and a heat pump (HP). Current values of costs and efficiencies make ST system remains as the most favorable option. These parameters may vary significantly over time. The evolution of these parameters may convert PV systems into the most favorable option for particular applications.

Effects of space environment on composites: An analytical study of critical experimental parameters

NASA Technical Reports Server (NTRS)

Gupta, A.; Carroll, W. F.; Moacanin, J.

1979-01-01

A generalized methodology currently employed at JPL, was used to develop an analytical model for effects of high-energy electrons and interactions between electron and ultraviolet effects. Chemical kinetic concepts were applied in defining quantifiable parameters; the need for determining short-lived transient species and their concentration was demonstrated. The results demonstrates a systematic and cost-effective means of addressing the issues and show qualitative and quantitative, applicable relationships between space radiation and simulation parameters. An equally important result is identification of critical initial experiments necessary to further clarify the relationships. Topics discussed include facility and test design; rastered vs. diffuse continuous e-beam; valid acceleration level; simultaneous vs. sequential exposure to different types of radiation; and interruption of test continuity.

Effect of feeding different dietary levels of energy and protein on growth performance and immune status of Vanaraja chicken in the tropic.

PubMed

Perween, Shahla; Kumar, Kaushalendra; Chandramoni; Kumar, Sanjay; Singh, Pankaj Kumar; Kumar, Manoj; Dey, Amitava

2016-08-01

The present study was conducted to observe the effect of feeding dietary level of energy and protein on growth performance and immune status of Vanaraja chicken in the tropic. The experiment was conducted for 56 days on 540 1-day-old chicks, which were individually weighed and distributed into nine groups having 60 birds in each. Each group was further subdivided into triplicates having 20 birds in each. Nine different experimental rations were formulated with three levels of protein, viz., 17%, 19%, and 21%; each with three levels of energy (2600, 2800, and 3000 kcal metabolizable energy [ME]/kg), respectively. Group T8 serves as control fed with 21% protein and 2800 kcal energy as per Project Directorate of Poultry, Hyderabad given requirement. Feed consumption, live weight gain, body weight change, and feed conversion ratio (FCR) were calculated based on the amount of feed consumed every week. All the birds were vaccinated following standard protocol. The hemagglutination inhibition (HI) test have been performed to assess the immunity potential of birds due to dietary effect, and serum samples were subjected to HI test at 7, 14, 21, and 28 days of age. Finally, economics of broiler production was calculated on the cost of feed per kg live weight gain. This study revealed that the effect of feeding different levels of energy and protein on growth parameters such as body weight gain and FCR was found to be significantly higher (p<0.05) containing 19% and 21% crude protein with 3000 kcal ME/kg in Vanaraja birds. There was a gradual increase in antibody titer against New castle disease virus as the level of protein and energy increase. It is speculated that the better body weight gain corroborate health and antibody titer. Moreover, the better immune response recorded in the study might be due to better nutrient utilization and its extension toward the better immune response. Higher energy with medium protein diet positively reflects to obtain desirable performance economically. It was positive inclination toward ration containing high protein and energy which influence the immune response of Vanaraja birds to obtained desirable performance economically also.

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

Krishnan, Venkat; Cole, Wesley

This poster is based on the paper of the same name, presented at the IEEE Power & Energy Society General Meeting, July18, 2016. Power sector capacity expansion models (CEMs) have a broad range of spatial resolutions. This paper uses the Regional Energy Deployment System (ReEDS) model, a long-term national scale electric sector CEM, to evaluate the value of high spatial resolution for CEMs. ReEDS models the United States with 134 load balancing areas (BAs) and captures the variability in existing generation parameters, future technology costs, performance, and resource availability using very high spatial resolution data, especially for wind and solarmore » modeled at 356 resource regions. In this paper we perform planning studies at three different spatial resolutions - native resolution (134 BAs), state-level, and NERC region level - and evaluate how results change under different levels of spatial aggregation in terms of renewable capacity deployment and location, associated transmission builds, and system costs. The results are used to ascertain the value of high geographically resolved models in terms of their impact on relative competitiveness among renewable energy resources.« less

The influence of regional geological settings on the seismic hazard level in copper mines in the Legnica-Głogów Copper Belt Area (Poland)

NASA Astrophysics Data System (ADS)

Burtan, Zbigniew

2017-11-01

The current level of rockburst hazard in copper mines of the (LGOM) Legnica- Głogów Copper Belt Area is mostly the consequence of mining-induced seismicity, whilst the majority of rockbursting events registered to date were caused by high-energy tremors. The analysis of seismic readings in recent years reveals that the highest seismic activity among the copper mines in the LGOM is registered in the mine Rudna. This study investigates the seismic activity in the rock strata in the Rudna mine fields over the years 2006-2015. Of particular interest are the key seismicity parameters: the number of registered seismic events, the total energy emissions, the energy index. It appears that varied seismic activity in the area may be the function of several variables: effective mining thickness, the thickness of burst-prone strata and tectonic intensity. The results support and corroborate the view that principal factors influencing the actual seismic hazard level are regional geological conditions in the copper mines within the Legnica-Głogów Copper Belt Area.

Use of Metal Oxide Nanoparticle Band Gap to Develop a Predictive Paradigm for Oxidative Stress and Acute Pulmonary Inflammation

PubMed Central

Zhang, Haiyuan; Ji, Zhaoxia; Xia, Tian; Meng, Huan; Low-Kam, Cecile; Liu, Rong; Pokhrel, Suman; Lin, Sijie; Wang, Xiang; Liao, Yu-Pei; Wang, Meiying; Li, Linjiang; Rallo, Robert; Damoiseaux, Robert; Telesca, Donatello; Mädler, Lutz; Cohen, Yoram; Zink, Jeffrey I.; Nel, Andre E.

2014-01-01

We demonstrate for 24 metal oxide (MOx) nanoparticles that it is possible to use conduction band energy levels to delineate their toxicological potential at cellular and whole animal levels. Among the materials, the overlap of conduction band energy (Ec) levels with the cellular redox potential (−4.12 to −4.84 eV) was strongly correlated to the ability of Co3O4, Cr2O3, Ni2O3, Mn2O3 and CoO nanoparticles to induce oxygen radicals, oxidative stress and inflammation. This outcome is premised on permissible electron transfers from the biological redox couples that maintain the cellular redox equilibrium to the conduction band of the semiconductor particles. Both single parameter cytotoxic as well as multi-parameter oxidative stress assays in cells showed excellent correlation to the generation of acute neutrophilic inflammation and cytokine responses in the lungs of CB57 Bl/6 mice. Co3O4, Ni2O3, Mn2O3 and CoO nanoparticles could also oxidize cytochrome c as a representative redox couple involved in redox homeostasis. While CuO and ZnO generated oxidative stress and acute pulmonary inflammation that is not predicted by Ec levels, the adverse biological effects of these materials could be explained by their solubility, as demonstrated by ICP-MS analysis. Taken together, these results demonstrate, for the first time, that it is possible to predict the toxicity of a large series of MOx nanoparticles in the lung premised on semiconductor properties and an integrated in vitro/in vivo hazard ranking model premised on oxidative stress. This establishes a robust platform for modeling of MOx structure-activity relationships based on band gap energy levels and particle dissolution. This predictive toxicological paradigm is also of considerable importance for regulatory decision-making about this important class of engineered nanomaterials. PMID:22502734

Use of metal oxide nanoparticle band gap to develop a predictive paradigm for oxidative stress and acute pulmonary inflammation.

PubMed

Zhang, Haiyuan; Ji, Zhaoxia; Xia, Tian; Meng, Huan; Low-Kam, Cecile; Liu, Rong; Pokhrel, Suman; Lin, Sijie; Wang, Xiang; Liao, Yu-Pei; Wang, Meiying; Li, Linjiang; Rallo, Robert; Damoiseaux, Robert; Telesca, Donatello; Mädler, Lutz; Cohen, Yoram; Zink, Jeffrey I; Nel, Andre E

2012-05-22

We demonstrate for 24 metal oxide (MOx) nanoparticles that it is possible to use conduction band energy levels to delineate their toxicological potential at cellular and whole animal levels. Among the materials, the overlap of conduction band energy (E(c)) levels with the cellular redox potential (-4.12 to -4.84 eV) was strongly correlated to the ability of Co(3)O(4), Cr(2)O(3), Ni(2)O(3), Mn(2)O(3), and CoO nanoparticles to induce oxygen radicals, oxidative stress, and inflammation. This outcome is premised on permissible electron transfers from the biological redox couples that maintain the cellular redox equilibrium to the conduction band of the semiconductor particles. Both single-parameter cytotoxic as well as multi-parameter oxidative stress assays in cells showed excellent correlation to the generation of acute neutrophilic inflammation and cytokine responses in the lungs of C57 BL/6 mice. Co(3)O(4), Ni(2)O(3), Mn(2)O(3), and CoO nanoparticles could also oxidize cytochrome c as a representative redox couple involved in redox homeostasis. While CuO and ZnO generated oxidative stress and acute pulmonary inflammation that is not predicted by E(c) levels, the adverse biological effects of these materials could be explained by their solubility, as demonstrated by ICP-MS analysis. These results demonstrate that it is possible to predict the toxicity of a large series of MOx nanoparticles in the lung premised on semiconductor properties and an integrated in vitro/in vivo hazard ranking model premised on oxidative stress. This establishes a robust platform for modeling of MOx structure-activity relationships based on band gap energy levels and particle dissolution. This predictive toxicological paradigm is also of considerable importance for regulatory decision-making about this important class of engineered nanomaterials.

In vitro gas production of foliage from three browse tree species treated with different dose levels of exogenous fibrolytic enzymes.

PubMed

López, D; Vázquez-Armijo, J F; López-Villalobos, N; Lee-Rangel, H A; Salem, A Z M; Borquez-Gastelum, J L; Domínguez-Vara, I A; Rojo-Rubio, R

2016-10-01

The aim of this study was to evaluate the effect of different dose levels of exogenous fibrolytic enzymes (EFE) on in vitro ruminal fermentation kinetics and energy utilization of foliages from three browse trees (Pithecellobium dulce, Heliocarpus velutinus and Guazuma ulmifolia). Mixture of EFE product was added to the leaves of the three browse tree species at three dose levels: 0 (control), 3.5 and 7.0 mg/g of DM. Chemical composition of the foliages, including plant secondary metabolites such as total phenolics (TP), saponins (SAP) and aqueous fraction (AF), was determined. In addition, in vitro assaying of ruminal gas production kinetics was determined for the three browse three foliages treated with EFE. P. dulce had the highest crude protein content (p < 0.05), whereas G. ulmifolia had the highest content of neutral detergent fibre and SAP (p < 0.05) and H. velutinus had the lowest content of TP (p < 0.05). The interaction between tree species and dose level of EFE was significant (p < 0.05) for gas production (GP) at 24 h of incubation, parameters b and c of the accumulated GP curve, short-chain fatty acids (SCFA) and metabolizable energy (ME). The lowest (p < 0.01) extent of accumulated GP as well as the b and c values occurred in G. ulmifolia at 0 mg EFE/g DM. P. dulce had the highest (p < 0.05) values for ME and SCFA at the highest dose of EFE. Tree species and dose level had significant (p < 0.05) effects on all parameters describing in vitro ruminal fermentation kinetics and energy utilization. Addition of EFE improved the fermentation kinetics of the browse species considered in this study. Journal of Animal Physiology and Animal Nutrition © 2016 Blackwell Verlag GmbH.

Study on the spectroscopic parameters and transition probabilities of 25 low-lying states of the AlC+ cation

NASA Astrophysics Data System (ADS)

Zhang, Jicai; Shi, Deheng; Xing, Wei; Sun, Jinfeng; Zhu, Zunlue

2017-11-01

This paper investigates the spectroscopic parameters and transition probabilities of 25 low-lying states, which come from the first five dissociation channels of AlC+ cation. The potential energy curves are calculated with the complete active space self-consistent field method, which is followed by the valence internally contracted multireference configuration interaction approach with Davidson correction. Of these 25 states, only the 35Σ-state is repulsive; the c1Σ+, f1Π, and 15Π states have the double well; the first well of c1Σ+ state and the second well of 15Π state are very weakly bound; the first well of c1Σ+ state has no vibrational levels; the 25Π state and the double well of f1Π state have only several vibrational states; the B3Σ-, E3Σ+, D3Π, 15Σ+, 25Σ-, and 15Π states are inverted when the spin-orbit coupling effect is included. The avoided crossings exist between the B3Σ- and 33Σ- states, the c1Σ+ and d1Σ+ states, the f1Π and 31Π states, the 15Π and 25Π states, as well as the 25Π and 35Π states. Core-valence correlation and scalar relativistic corrections are considered. The extrapolation of potential energies to the complete basis set limit is done. The spectroscopic parameters and vibrational levels are determined for all the Λ-S and Ω bound states. The transition dipole moments are calculated. Franck-Condon factors of a great number of electronic transitions are evaluated. On the whole, the spin-orbit coupling effect on the spectroscopic parameters and vibrational levels is small except for very few states. The results determined in this paper could provide some powerful guidelines to observe these states in a spectroscopy experiment.

Neutron resonance parameters of 6830Zn+n and statistical distributions of level spacings and widths

NASA Astrophysics Data System (ADS)

Garg, J. B.; Tikku, V. K.; Harvey, J. A.; Halperin, J.; Macklin, R. L.

1982-04-01

Discrete values of the parameters (E0, gΓn, Jπ, Γγ, etc.) of the resonances in the reaction 6830Zn + n have been determined from total cross section measurements from a few keV to 380 keV with a nominal resolution of 0.07 ns/m for the highest energy and from capture cross section measurements up to 130 keV using the pulsed neutron time-of-flight technique with a neutron burst width of 5 ns. The cross section data were analyzed to determine the parameters of the resonances using R-matrix multilevel codes. These results have provided values of average quantities as follows: S0=(2.01+/-0.34), S1=(0.56+/-0.05), S2=(0.2+/-0.1) in units of 10-4, D0=(5.56+/-0.43) keV and D1=(1.63+/-0.14) keV. From these measurements we have also determined the following average radiation widths: (Γ¯γ)l=0=(302+/-60) meV and (Γ¯γ)l=1=(157 +/-7) meV. The investigation of the statistical properties of neutron reduced widths and level spacings showed excellent agreement of the data with the Porter-Thomas distribution for s- and p-wave neutron widths and with the Dyson-Mehta Δ3 statistic and the Wigner distribution for the s-wave level spacing distribution. In addition, a correlation coefficient of ρ=0.50+/-0.10 between Γ0n and Γγ has been observed for s-wave resonances. The value of <σnγ> at (30+/-10) keV is 19.2 mb. NUCLEAR REACTIONS 3068Zn(n,n), 3068Zn(n,γ), E=few keV to 380, 130 keV, respectively. Measured total and capture cross sections versus neutron energy, deduced resonance parameters, E0, Jπ, gΓn, Γγ, S0, S1, S2, D0, D1.

Novel effects of the cannabinoid inverse agonist AM 251 on parameters related to metabolic syndrome in obese Zucker rats.

PubMed

Merroun, Ikram; Sánchez-González, Cristina; Martínez, Rosario; López-Chaves, Carlos; Porres, Jesús M; Aranda, Pilar; Llopis, Juan; Galisteo, Milagros; Zarzuelo, Antonio; Errami, Mohammed; López-Jurado, María

2013-11-01

Recent research suggests that cannabinoid receptor CB1 antagonists can affect appetite and body weight gain, although their influence on other parameters related to metabolic syndrome is not well documented. The present study was designed to assess the effects of chronic treatment with the CB1 receptor inverse agonist AM 251 (3 mg/kg for 3 weeks) in obese and lean Zucker rats on parameters related to metabolic syndrome. Four groups of rats were used: lean Zucker rats, untreated obese Zucker rats, AM 251-treated obese Zucker rats and a pair-fed obese Zucker rat experimental group which received the same amount of food as that consumed by the animals treated with AM251. Food intake, body weight gain, energy expenditure, plasma biochemical parameters, leptin, insulin and hepatic status markers were analysed. Daily injection of AM 251 in obese Zucker rats produced a marked and sustained decrease in daily food intake and body weight and a considerable increase in energy expenditure in comparison with untreated obese Zucker rats. AM 251 administration to obese rats significantly reduced plasma levels of glucose, leptin, AST, ALT, Gamma GT, total bilirubin and LDL cholesterol whereas HDL cholesterol plasma levels increased. The results also showed a decrease in liver/weight body ratio and total fat content in the liver. The main effects of AM251 (3 mg/kg) found in this study were not observed in pair-fed obese animals, highlighting the additional beneficial effects of treatment with AM 251. The results obtained in obese rats can be interpreted as a decrease in leptin and insulin resistance, thereby improving glucose and lipid metabolism, alleviating the steatosis present in the metabolic syndrome and thus favourably modifying plasma levels of hepatic biomarkers. Our results indicate that the cannabinoid CB1 inverse agonist AM 251 represents a promising therapeutic strategy for the treatment of obesity and metabolic syndrome. © 2013.

High scale flavor alignment in two-Higgs doublet models and its phenomenology

DOE PAGES

Gori, Stefania; Haber, Howard E.; Santos, Edward

2017-06-21

The most general two-Higgs doublet model (2HDM) includes potentially large sources of flavor changing neutral currents (FCNCs) that must be suppressed in order to achieve a phenomenologically viable model. The flavor alignment ansatz postulates that all Yukawa coupling matrices are diagonal when expressed in the basis of mass-eigenstate fermion fields, in which case tree-level Higgs-mediated FCNCs are eliminated. In this work, we explore models with the flavor alignment condition imposed at a very high energy scale, which results in the generation of Higgs-mediated FCNCs via renormalization group running from the high energy scale to the electroweak scale. Using the currentmore » experimental bounds on flavor changing observables, constraints are derived on the aligned 2HDM parameter space. In the favored parameter region, we analyze the implications for Higgs boson phenomenology.« less

Instant preheating in quintessential inflation with α -attractors

NASA Astrophysics Data System (ADS)

Dimopoulos, Konstantinos; Wood, Leonora Donaldson; Owen, Charlotte

2018-03-01

We investigate a compelling model of quintessential inflation in the context of α -attractors, which naturally result in a scalar potential featuring two flat regions; the inflationary plateau and the quintessential tail. The "asymptotic freedom" of α -attractors, near the kinetic poles, suppresses radiative corrections and interactions, which would otherwise threaten to lift the flatness of the quintessential tail and cause a 5th-force problem respectively. Since this is a nonoscillatory inflation model, we reheat the Universe through instant preheating. The parameter space is constrained by both inflation and dark energy requirements. We find an excellent correlation between the inflationary observables and model predictions, in agreement with the α -attractors setup. We also obtain successful quintessence for natural values of the parameters. Our model predicts potentially sizeable tensor perturbations (at the level of 1%) and a slightly varying equation of state for dark energy, to be probed in the near future.

Modeling the low-velocity impact characteristics of woven glass epoxy composite laminates using artificial neural networks

NASA Astrophysics Data System (ADS)

Mathivanan, N. Rajesh; Mouli, Chandra

2012-12-01

In this work, a new methodology based on artificial neural networks (ANN) has been developed to study the low-velocity impact characteristics of woven glass epoxy laminates of EP3 grade. To train and test the networks, multiple impact cases have been generated using statistical analysis of variance (ANOVA). Experimental tests were performed using an instrumented falling-weight impact-testing machine. Different impact velocities and impact energies on different thicknesses of laminates were considered as the input parameters of the ANN model. This model is a feed-forward back-propagation neural network. Using the input/output data of the experiments, the model was trained and tested. Further, the effects of the low-velocity impact response of the laminates at different energy levels were investigated by studying the cause-effect relationship among the influential factors using response surface methodology. The most significant parameter is determined from the other input variables through ANOVA.

Resonance tunneling electron-vibrational spectroscopy of polyoxometalates.

PubMed

Dalidchik, F I; Kovalevskii, S A; Balashov, E M

2017-05-21

The tunneling spectra of the ordered monolayer films of decamolybdodicobaltate (DMDC) compounds deposited from aqueous solutions on HOPG were measured by scanning tunnel microscopy in air. The DMDC spectra, as well as the tunneling spectra of other polyoxometalates (POMs), exhibit well-defined negative differential resistances (NDRs). The mechanism of formation of these spectral features was established from the collection of revealed NDR dependences on the external varying parameters and found to be common to all systems exhibiting Wannier-Stark localization. A model of biresonance tunneling was developed to provide an explanation for the totality of experimental data, both the literature and original, on the tunneling POM probing. A variant of the tunneling electron-vibrational POM spectroscopy was proposed allowing the determination of the three basic energy parameters-energy gaps between the occupied and unoccupied states, frequencies of the vibrational transitions accompanying biresonance electron-tunneling processes, and electron-vibrational interaction constants on the monomolecular level.

Geohydrology and evapotranspiration at Franklin Lake playa, Inyo County, California

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

Czarnecki, J.B.

1997-12-31

Franklin Lake playa is one of the principal discharge areas of the Furnace Creek Ranch-Alkali Flat ground-water-flow system in southern Nevada and adjacent California. Yucca Mountain, Nevada, located within this flow system, is being evaluated by the US Department of Energy to determine its suitability as a potential site for a high-level nuclear-waste repository. To assist the U.S. Department of Energy with its evaluation of the Yucca Mountain site, the US Geological Survey developed a parameter-estimation model of the Furnace Creek Ranch-Alkali Flat ground-water-flow system. Results from sensitivity analyses made using the parameter-estimation model indicated that simulated rates of evapotranspirationmore » at Franklin Lake playa had the largest effect on the calculation of transmissivity values at Yucca Mountain of all the model-boundary conditions and, therefore, that evapotranspiration required careful definition.« less

Effects of a nonnutritive sweetener on body adiposity and energy metabolism in mice with diet-induced obesity.

PubMed

Mitsutomi, Kimihiko; Masaki, Takayuki; Shimasaki, Takanobu; Gotoh, Koro; Chiba, Seiichi; Kakuma, Tetsuya; Shibata, Hirotaka

2014-01-01

Nonnutritive sweeteners (NNSs) have been studied in terms of their potential roles in type 2 diabetes, obesity, and related metabolic disorders. Several studies have suggested that NNSs have several specific effects on metabolism such as reduced postprandial hyperglycemia and insulin resistance. However, the detailed effects of NNSs on body adiposity and energy metabolism have not been fully elucidated. We investigated the effects of an NNS on energy metabolism in mice with diet-induced obesity (DIO). DIO mice were divided into NNS-administered (4% NNS in drinking water), sucrose-administered (33% sucrose in drinking water), and control (normal water) groups. After supplementation for 4 weeks, metabolic parameters, including uncoupling protein (UCP) levels and energy expenditure, were assessed. Sucrose supplementation increased hyperglycemia, body adiposity, and body weight compared to the NNS-administered and control groups (P<0.05 for each). In addition, NNS supplementation decreased hyperglycemia compared to the sucrose-administered group (P<0.05). Interestingly, NNS supplementation increased body adiposity, which was accompanied by hyperinsulinemia, compared to controls (P<0.05 for each). NNS also increased leptin levels in white adipose tissue and triglyceride levels in tissues compared to controls (P<0.05 for each). Notably, compared to controls, NNS supplementation decreased the UCP1 level in brown adipose tissue and decreased O2 consumption in the dark phase. NNSs may be good sugar substitutes for people with hyperglycemia, but appear to influence energy metabolism in DIO mice. © 2013.

Resummation of divergent perturbation series: Application to the vibrational states of H{sub 2}CO molecule

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

Duchko, A. N.; V.E. Zuev Institute of Atmospheric Optics, Tomsk; Bykov, A. D., E-mail: adbykov@rambler.ru

2015-10-21

Large-order Rayleigh–Schrödinger perturbation theory (RSPT) is applied to the calculation of anharmonic vibrational energy levels of H{sub 2}CO molecule. We use the model of harmonic oscillators perturbed by anharmonic terms of potential energy. Since the perturbation series typically diverge due to strong couplings, we apply the algebraic approximation technique because of its effectiveness shown earlier by Goodson and Sergeev [J. Chem. Phys. 110, 8205 (1999); ibid. 124, 094111 (2006)] and in our previous articles [A. D. Bykov et al. Opt. Spectrosc. 114, 396 (2013); ibid. 116, 598 (2014)]. To facilitate the resummation of terms contributing to perturbed states, when resonancemore » mixing between states is especially strong and perturbation series diverge very quick, we used repartition of the Hamiltonian by shifting the normal mode frequencies. Energy levels obtained by algebraic approximants were compared with the results of variational calculation. It was found that for low energy states (up to ∼5000 cm{sup −1}), algebraic approximants gave accurate values of energy levels, which were in excellent agreement with the variational method. For highly excited states, strong and multiple resonances complicate series resummation, but a suitable change of normal mode frequencies allows one to reduce the resonance mixing and to get accurate energy levels. The theoretical background of the problem of RSPT series divergence is discussed along with its numerical analysis. For these purposes, the vibrational energy is considered as a function of a complex perturbation parameter. Layout and classification of its singularities allow us to model the asymptotic behavior of the perturbation series and prove the robustness of the algorithm.« less

Optoelectronic studies on heterocyclic bases of deoxyribonucleic acid for DNA photonics.

PubMed

El-Diasty, Fouad; Abdel-Wahab, Fathy

2015-10-01

The optoelectronics study of large molecules, particularly π-stacking molecules, such as DNA is really an extremely difficult task. We perform first electronic structure calculations on the heterocyclic bases of 2'-deoxyribonucleic acid based on Lorentz-Fresnel dispersion theory. In the UV-VIS range of spectrum, many of the optoelectronic parameters for DNA four bases namely adenine, guanine, cytosine and thymine are calculated and discussed. The results demonstrate that adenine has the highest hyperpolarizability, whereas thymine has the lowest hyperpolarizability. Cytosine has the lower average oscillator energy and the higher lattice energy. Thymine infers the most stable nucleic base with the lower phonon energy. Thymine also has the highest average oscillator energy and the lower lattice energy. Moreover, the four nucleic acid bases have large band gap energies less than 5 eV with a semiconducting behavior. Guanine shows the smallest band gap and the highest Fermi level energy, whereas adenine elucidates the highest band gap energy. Copyright © 2015. Published by Elsevier B.V.

BOREAS Level-3b Landsat TM Imagery: At-sensor Radiances in BSQ Format

NASA Technical Reports Server (NTRS)

Hall, Forrest G. (Editor); Nickeson, Jaime; Knapp, David; Newcomer, Jeffrey A.; Cihlar, Josef

2000-01-01

For BOREAS, the level-3b Landsat TM data, along with the other remotely sensed images, were collected in order to provide spatially extensive information over the primary study areas. This information includes radiant energy, detailed land cover, and biophysical parameter maps such as FPAR and LAI. Although very similar in content to the level-3a Landsat TM products, the level-3b images were created to provide users with a directly usable at-sensor radiance image. Geographically, the level-3b images cover the BOREAS NSA and SSA. Temporally, the images cover the period of 22-Jun-1984 to 09-Jul-1996. The images are available in binary, image format files.

Poole-Frenkel-effect as dominating current mechanism in thin oxide films—An illusion?!

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

Schroeder, Herbert

2015-06-07

In many of the publications, over 50 per year for the last five years, the Poole-Frenkel-effect (PFE) is identified or suggested as dominating current mechanism to explain measured current–electric field dependencies in metal-insulator-metal (MIM) thin film stacks. Very often, the insulating thin film is a metal oxide as this class of materials has many important applications, especially in information technology. In the overwhelming majority of the papers, the identification of the PFE as dominating current mechanism is made by the slope of the current–electric field curve in the so-called Poole-Frenkel plot, i.e., logarithm of current density, j, divided by themore » applied electric field, F, versus the square root of that field. This plot is suggested by the simplest current equation for the PFE, which comprises this proportionality (ln(j/F) vs. F{sup 1/2}) leading to a straight line in this plot. Only one other parameter (except natural constants) may influence this slope: the optical dielectric constant of the insulating film. In order to identify the importance of the PFE simulation studies of the current through MIM stacks with thin insulating films were performed and the current–electric field curves without and with implementation of the PFE were compared. For the simulation, an advanced current model has been used combining electronic carrier injection/ejection currents at the interfaces, described by thermionic emission, with the carrier transport in the dielectric, described by drift and diffusion of electrons and holes in a wide band gap semiconductor. Besides the applied electric field (or voltage), many other important parameters have been varied: the density of the traps (with donor- and acceptor-like behavior); the zero-field energy level of the traps within the energy gap, this energy level is changed by the PFE (also called internal Schottky effect); the thickness of the dielectric film; the permittivity of the dielectric film simulating different oxide materials; the barriers for electrons and holes at the interfaces simulating different electrode materials; the temperature. The main results and conclusions are: (1) For a single type of trap present only (donor-like or acceptor-like), none of the simulated current density curves shows the expected behavior of the PFE and in most cases within the tested parameter field the effect of PFE is negligibly small. (2) For both types of traps present (compensation) only in the case of exact compensation, the expected slope in the PF-plot was nearly found for a wider range of the applied electric field, but for a very small range of the tested parameter field because of the very restricting additional conditions: first, the quasi-fermi level of the current controlling particle (electrons or holes) has to be 0.1 to 0.5 eV closer to the respective band limit than the zero-field energy level of the respective traps and, second, the compensating trap energy level has to be shallow. The conclusion from all these results is: the observation of the PFE as dominating current mechanism in MIM stacks with thin dielectric (oxide) films (typically 30 nm) is rather improbable!.« less

Transfer of a wave packet in double-well potential

NASA Astrophysics Data System (ADS)

Yang, Hai-Feng; Hu, Yao-Hua; Tan, Yong-Gang

2018-04-01

Energy potentials with double-well structures are typical in atoms and molecules systems. A manipulation scheme using Half Cycles Pulses (HCPs) is proposed to transfer a Gaussian wave packet between the two wells. On the basis of quantum mechanical simulations, the time evolution and the energy distribution of the wave packet are evaluated. The effect of time parameters, amplitude, and number of HCPs on spatial and energy distribution of the final state and transfer efficiency are investigated. After a carefully tailored HCPs sequence is applied to the initial wave packet localized in one well, the final state is a wave packet localized in the other well and populated at the lower energy levels with narrower distribution. The present scheme could be used to control molecular reactions and to prepare atoms with large dipole moments.

Sustainable solar energy capability studies by using S2H model in treating groundwater supply

NASA Astrophysics Data System (ADS)

Musa, S.; Anuar, M. F.; Shahabuddin, M. M.; Ridzuan, M. B.; Radin Mohamed, R. M. S.; Madun, M. A.

2018-04-01

Groundwater extracted in Research Centre for Soft Soil Malaysia (RECESS) contains a number of pollutants that exceed the safe level for consumption. A Solar-Hydro (S2H) model which is a practical prototype has been introduced to treat the groundwater sustainably by solar energy process (evaporation method). Selected parameters was tested which are sulphate, nitrate, chloride, fluoride, pH and dissolved oxygen. The water quality result shows that all parameters have achieved 100% of the drinking water quality standard issued by the Ministry of Health Malaysia. Evaporation method was proven that this solar energy can be applied in sustainably treating groundwater quality with up to 90% effectiveness. On the other hand, the quantitative analysis has shown that the production of clean water is below than 2% according to time constraints and design factors. Thus, this study can be generate clean and fresh water from groundwater by using a simplified model and it has huge potential to be implemented by the local communities with a larger scale and affordable design.

Simulation studies for surfaces and materials strength

NASA Technical Reports Server (NTRS)

Halicioglu, T.

1986-01-01

During this reporting period three investigations were carried out. The first area of research concerned the analysis of the structure-energy relationship in small clusters. This study is very closely related to the improvement of the potential energy functions which are suitable and simple enough to be used in atomistic simulation studies. Parameters obtained from ab initio calculations for dimers and trimers of Al were used to estimate energetics and global minimum energy structures of clusters continuing up to 15 Al atoms. The second research topic addressed modeling of the collision process for atoms impinging on surfaces. In this simulation study qualitative aspects of the O atom collision with a graphite surface were analyzed. Four different O/graphite systems were considered and the aftermath of the impact was analyzed. The final area of investigation was related to the simulation of thin amorphous Si films on crystalline Si substrates. Parameters obtained in an earlier study were used to model an exposed amorphous Si surface and an a-Si/c-Si interface. Structural details for various film thicknesses were investigated at an atomistic level.

Lanthanide and transition metal complexes of bioactive coumarins: molecular modeling and spectroscopic studies.

PubMed

Georgieva, I; Mihaylov, Tz; Trendafilova, N

2014-06-01

The present paper summarizes theoretical and spectroscopic investigations on a series of active coumarins and their lanthanide and transition metal complexes with application in medicine and pharmacy. Molecular modeling as well as IR, Raman, NMR and electronic spectral simulations at different levels of theory were performed to obtain important molecular descriptors: total energy, formation energy, binding energy, stability, conformations, structural parameters, electron density distribution, molecular electrostatic potential, Fukui functions, atomic charges, and reactive indexes. The computations are performed both in gas phase and in solution with consideration of the solvent effect on the molecular structural and energetic parameters. The investigations have shown that the advanced computational methods are reliable for prediction of the metal-coumarin binding mode, electron density distribution, thermodynamic properties as well as the strength and nature of the metal-coumarin interaction (not experimentally accessible) and correctly interpret the experimental spectroscopic data. Known results from biological tests for cytotoxic, antimicrobial, anti-fungal, spasmolytic and anti-HIV activities on the studied metal complexes are reported and discussed. Copyright © 2014 Elsevier Inc. All rights reserved.

MRCI study on the spectroscopic parameters, transition dipole moments and transition probabilities of 16 low-lying states of the BeB radical

NASA Astrophysics Data System (ADS)

Zhou, Dan; Shi, Deheng; Sun, Jinfeng; Zhu, Zunlue

2018-03-01

In this work, we calculate the potential energy curves of 16 Λ-S and 36 Ω states of beryllium boride (BeB) radical using the complete active space self-consistent field method, followed by the valence internally contracted multireference configuration interaction approach with Davidson correction. The 16 Λ-S states are the X2Π, A2Σ+, B2Π, C2Δ, D2Ʃ-, E2Σ+, G2Π, I2Σ+, a4Σ-, b4Π, c4Σ-, d4Δ, e4Σ+, g4Π, h4Π, and 24Σ+, which are obtained from the first three dissociation channels of the BeB radical. The Ω states are obtained from the Λ-S states. Of the Λ-S states, the G2Π, I2Σ+, and h4Π states exhibit double well curves. The G2Π, b4Π, and g4Π states are inverted with the spin-orbit coupling effect included. The d4Δ, e4Σ+, and g4Π states as well as the second well of the h4Π state are very weakly bound. Avoided crossings exist between the G2Π and H2Π states, the A2Σ+ and E2Σ+ states, the c4Σ- and f4Σ- states, the g4Π and h4Π states, the I2Σ+ and 42Σ+ states, as well as the 24Σ+ and 34Σ+ states. To improve the quality of the potential energy curves, core-valence correlation and scalar relativistic corrections, as well as the extrapolation of the potential energies to the complete basis set limit, are included. The transition dipole moments are computed. Spectroscopic parameters and vibrational levels are determined along with Franck-Condon factors, Einstein coefficients, and radiative lifetimes of many electronic transitions. The transition probabilities are evaluated. The spin-orbit coupling effect on the spectroscopic parameters and vibrational levels is discussed. The spectroscopic parameters, vibrational levels, and transition probabilities reported in this paper can be considered very reliable and can be employed to predict these states in an appropriate spectroscopy experiment.

Photoionization of rare gas clusters

NASA Astrophysics Data System (ADS)

Zhang, Huaizhen

This thesis concentrates on the study of photoionization of van der Waals clusters with different cluster sizes. The goal of the experimental investigation is to understand the electronic structure of van der Waals clusters and the electronic dynamics. These studies are fundamental to understand the interaction between UV-X rays and clusters. The experiments were performed at the Advanced Light Source at Lawrence Berkeley National Laboratory. The experimental method employs angle-resolved time-of-flight photoelectron spectrometry, one of the most powerful methods for probing the electronic structure of atoms, molecules, clusters and solids. The van der Waals cluster photoionization studies are focused on probing the evolution of the photoelectron angular distribution parameter as a function of photon energy and cluster size. The angular distribution has been known to be a sensitive probe of the electronic structure in atoms and molecules. However, it has not been used in the case of van der Waals clusters. We carried out outer-valence levels, inner-valence levels and core-levels cluster photoionization experiments. Specifically, this work reports on the first quantitative measurements of the angular distribution parameters of rare gas clusters as a function of average cluster sizes. Our findings for xenon clusters is that the overall photon-energy-dependent behavior of the photoelectrons from the clusters is very similar to that of the corresponding free atoms. However, distinct differences in the angular distribution point at cluster-size-dependent effects were found. For krypton clusters, in the photon energy range where atomic photoelectrons have a high angular anisotropy, our measurements show considerably more isotropic angular distributions for the cluster photoelectrons, especially right above the 3d and 4p thresholds. For the valence electrons, a surprising difference between the two spin-orbit components was found. For argon clusters, we found that the angular distribution parameter values of the two-spin-orbit components from Ar 2p clusters are slightly different. When comparing the beta values for Ar between atoms and clusters, we found different results between Ar 3s atoms and clusters, and between Ar 3p atoms and clusters. Argon cluster resonance from surface and bulk were also measured. Furthermore, the angular distribution parameters of Ar cluster photoelectrons and Ar atom photoelectrons in the 3s → np ionization region were obtained.

Determination of the nuclear level densities and radiative strength function for 43 nuclei in the mass interval 28≤A≤200

NASA Astrophysics Data System (ADS)

Knezevic, David; Jovancevic, Nikola; Sukhovoj, Anatoly M.; Mitsyna, Ludmila V.; Krmar, Miodrag; Cong, Vu D.; Hambsch, Franz-Josef; Oberstedt, Stephan; Revay, Zsolt; Stieghorst, Christian; Dragic, Aleksandar

2018-03-01

The determination of nuclear level densities and radiative strength functions is one of the most important tasks in low-energy nuclear physics. Accurate experimental values of these parameters are critical for the study of the fundamental properties of nuclear structure. The step-like structure in the dependence of the level densities p on the excitation energy of nuclei Eex is observed in the two-step gamma cascade measurements for nuclei in the 28 ≤ A ≤ 200 mass region. This characteristic structure can be explained only if a co-existence of quasi-particles and phonons, as well as their interaction in a nucleus, are taken into account in the process of gamma-decay. Here we present a new improvement to the Dubna practical model for the determination of nuclear level densities and radiative strength functions. The new practical model guarantees a good description of the available intensities of the two step gamma cascades, comparable to the experimental data accuracy.

Anaerobic digestion of thin stillage for energy recovery and water reuse in corn-ethanol plants.

PubMed

Alkan-Ozkaynak, A; Karthikeyan, K G

2011-11-01

Recycling of anaerobically-digested thin stillage within a corn-ethanol plant may result in the accumulation of nutrients of environmental concern in animal feed coproducts and inhibitory organic materials in the fermentation tank. Our focus is on anaerobic digestion of treated (centrifugation and lime addition) thin stillage. Suitability of digestate from anaerobic treatment for reuse as process water was also investigated. Experiments conducted at various inoculum-to-substrate ratios (ISRs) revealed that alkalinity is a critical parameter limiting digestibility of thin stillage. An ISR level of 2 appeared optimal based on high biogas production level (763 mL biogas/g volatile solids added) and organic matter removal (80.6% COD removal). The digester supernatant at this ISR level was found to contain both organic and inorganic constituents at levels that would cause no inhibition to ethanol fermentation. Anaerobic digestion of treated-thin stillage can be expected to improve the water and energy efficiencies of dry grind corn-ethanol plants. Copyright © 2011 Elsevier Ltd. All rights reserved.

Regulation of plasma factor XIII levels in healthy individuals; a major impact by subunit B intron K c.1952+144 C>G polymorphism.

PubMed

Mezei, Zoltán A; Katona, Éva; Kállai, Judit; Bereczky, Zsuzsanna; Molnár, Éva; Kovács, Bettina; Ajzner, Éva; Bagoly, Zsuzsa; Miklós, Tünde; Muszbek, László

2016-12-01

The regulation of plasma factor XIII (FXIII) levels in healthy individuals has been only partially explored. The identification of major non-genetic and genetic regulatory factors might provide important information on the contribution of FXIII to the risk of cardio/cerebrovascular diseases. To determine the effect of age, smoking, BMI, fibrinogen concentration on plasma FXIII activity, complex FXIII antigen (FXIII-A 2 B 2 ) and total FXIII-B subunit (tFXIII-B) level, to correlate FXIII-B level with the other two FXIII parameters and to assess the variation of FXIII levels in carriers of major FXIII subunit polymorphisms. 268 healthy individuals were enrolled in the study. FXIII activity was measured by the ammonia release assay; FXIII-A 2 B 2 and tFXIII-B were determined by ELISAs. FXIII-A p.Val34Leu, FXIII-B p.His95Arg and FXIII-B intron K c.1952+144 C>G polymorphisms were identified by RT-PCR using melting point analysis with fluorescence resonance energy transfer detection. All investigated FXIII parameters showed significant positive correlation with age and fibrinogen level; gender and BMI influenced only tFXIII-B. A highly significant positive correlation was demonstrated between tFXIII-B and the other FXIII parameters. FXIII-A p.Val34Leu polymorphism had only slight, if any effect on FXIII levels. The FXIII-B Arg95 allele moderately increased all three FXIII parameters, but the effect became statistically significant only after adjustment. The FXIII-B intron K G allele drastically decreased FXIII levels, and it seemed to be in synergism with the FXIII-A Leu34 allele. Plasma FXIII levels are subjected to multifactorial regulation, in which age, fibrinogen level and FXIII-B intron K polymorphism are major determinants. Copyright © 2016 Elsevier Ltd. All rights reserved.

Effects of environmental and water quality parameters on the functioning of copepod assemblages in tropical estuaries

NASA Astrophysics Data System (ADS)

Araujo, Adriana V.; Dias, Cristina O.; Bonecker, Sérgio L. C.

2017-07-01

We examined changes in the functioning of copepod assemblages with increasing pollution in estuaries, using sampling standardization of the salinity range to enable comparisons. Copepod assemblages were analyzed in four southeast Brazilian estuaries with different water quality levels and hydrodynamic characteristics over two years. We obtained mesozooplankton samples together with environmental and water quality parameters in the estuaries, every two months under predetermined salinities ranging from 15 to 25. The values of parameters, except species size, associated with the functioning of the copepod assemblages (biomass, productivity, and turnover rate) did not differ among estuaries. However, in the more polluted estuaries, the biomass and productivity of copepod assemblages of mesozooplankton were negatively correlated with concentration of pollution indicator parameters. Conversely, in the less polluted estuaries some degree of enrichment still seems to increase the system biomass and productivity, as these parameters were inversely related to indicators of improved water quality. The pollution level of estuaries distorted the relationship between temperature and the efficiency of converting energy to organic matter. In the less polluted estuaries, the relationship between turnover rate and temperature was over 70%, while in the most polluted estuaries, this relationship was only approximately 50%. Our results demonstrated that the functioning of assemblages in the estuaries was affected differently by increasing pollution depending on the water quality level of the system. Thus, investigating the functioning of assemblages can be a useful tool for the analysis of estuarine conditions.

Resonant scattering due to adatoms in graphene: Top, bridge, and hollow positions

NASA Astrophysics Data System (ADS)

Irmer, Susanne; Kochan, Denis; Lee, Jeongsu; Fabian, Jaroslav

2018-02-01

We present a theoretical study of resonance characteristics in graphene from adatoms with s or pz character binding in top, bridge, and hollow positions. The adatoms are described by two tight-binding parameters: on-site energy and hybridization strength. We explore a wide range of different magnitudes of these parameters by employing T -matrix calculations in the single adatom limit and by tight-binding supercell calculations for dilute adatom coverage. We calculate the density of states and the momentum relaxation rate and extract the resonance level and resonance width. The top position with a large hybridization strength or, equivalently, small on-site energy, induces resonances close to zero energy. The bridge position, compared to top, is more sensitive to variation in the orbital tight-binding parameters. Resonances within the experimentally relevant energy window are found mainly for bridge adatoms with negative on-site energies. The effect of resonances from the top and bridge positions on the density of states and momentum relaxation rate is comparable and both positions give rise to a power-law decay of the resonant state in graphene. The hollow position with s orbital character is affected from destructive interference, which is seen from the very narrow resonance peaks in the density of states and momentum relaxation rate. The resonant state shows no clear tendency to a power-law decay around the impurity and its magnitude decreases strongly with lowering the adatom content in the supercell calculations. This is in contrast to the top and bridge positions. We conclude our study with a comparison to models of pointlike vacancies and strong midgap scatterers. The latter model gives rise to significantly higher momentum relaxation rates than caused by single adatoms.

Atomic Radius and Charge Parameter Uncertainty in Biomolecular Solvation Energy Calculations

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

Yang, Xiu; Lei, Huan; Gao, Peiyuan

Atomic radii and charges are two major parameters used in implicit solvent electrostatics and energy calculations. The optimization problem for charges and radii is under-determined, leading to uncertainty in the values of these parameters and in the results of solvation energy calculations using these parameters. This paper presents a method for quantifying this uncertainty in solvation energies using surrogate models based on generalized polynomial chaos (gPC) expansions. There are relatively few atom types used to specify radii parameters in implicit solvation calculations; therefore, surrogate models for these low-dimensional spaces could be constructed using least-squares fitting. However, there are many moremore » types of atomic charges; therefore, construction of surrogate models for the charge parameter space required compressed sensing combined with an iterative rotation method to enhance problem sparsity. We present results for the uncertainty in small molecule solvation energies based on these approaches. Additionally, we explore the correlation between uncertainties due to radii and charges which motivates the need for future work in uncertainty quantification methods for high-dimensional parameter spaces.« less

Calibration by Hydrological Response Unit of a National Hydrologic Model to Improve Spatial Representation and Distribution of Parameters

NASA Astrophysics Data System (ADS)

Norton, P. A., II

2015-12-01

The U. S. Geological Survey is developing a National Hydrologic Model (NHM) to support consistent hydrologic modeling across the conterminous United States (CONUS). The Precipitation-Runoff Modeling System (PRMS) simulates daily hydrologic and energy processes in watersheds, and is used for the NHM application. For PRMS each watershed is divided into hydrologic response units (HRUs); by default each HRU is assumed to have a uniform hydrologic response. The Geospatial Fabric (GF) is a database containing initial parameter values for input to PRMS and was created for the NHM. The parameter values in the GF were derived from datasets that characterize the physical features of the entire CONUS. The NHM application is composed of more than 100,000 HRUs from the GF. Selected parameter values commonly are adjusted by basin in PRMS using an automated calibration process based on calibration targets, such as streamflow. Providing each HRU with distinct values that captures variability within the CONUS may improve simulation performance of the NHM. During calibration of the NHM by HRU, selected parameter values are adjusted for PRMS based on calibration targets, such as streamflow, snow water equivalent (SWE) and actual evapotranspiration (AET). Simulated SWE, AET, and runoff were compared to value ranges derived from multiple sources (e.g. the Snow Data Assimilation System, the Moderate Resolution Imaging Spectroradiometer (i.e. MODIS) Global Evapotranspiration Project, the Simplified Surface Energy Balance model, and the Monthly Water Balance Model). This provides each HRU with a distinct set of parameter values that captures the variability within the CONUS, leading to improved model performance. We present simulation results from the NHM after preliminary calibration, including the results of basin-level calibration for the NHM using: 1) default initial GF parameter values, and 2) parameter values calibrated by HRU.

What can we learn on supernova neutrino spectra with water Cherenkov detectors?

NASA Astrophysics Data System (ADS)

Gallo Rosso, Andrea; Vissani, Francesco; Volpe, Maria Cristina

2018-04-01

We investigate the precision with which the supernova neutrino spectra can be reconstructed in water Cherenkov detectors, in particular the large scale Hyper-Kamiokande and Super-Kamiokande. To this aim, we consider quasi-thermal neutrino spectra modified by the Mikheev-Smirnov-Wolfenstein effect for the case of normal ordering. We perform three 9 degrees of freedom likelihood analyses including first inverse-beta decay only, then the combination of inverse beta decay and elastic scattering on electrons and finally a third analysis that also includes neutral scattering neutrino-oxygen events. A tenth parameter is added in the analyses to account for the theoretical uncertainty on the neutral current neutrino-oxygen cross section. By assuming a 100% efficiency in Hyper-Kamiokande, we show that one can reconstruct the electron antineutrino average energy and pinching parameter with an accuracy of ~2% and ~7% percent respectively, while the antineutrino integrated luminosity can be pinned down at ~3% percent level. As for the muon and tau neutrinos, the average energy and the integrated luminosity can be measured with ~7% precision. These results represent a significant improvement with respect Super-Kamiokande, particularly for the pinching parameter defining the electron antineutrino spectra. As for electron neutrinos, the determination of the emission parameters requires the addition of supplementary detection channels.

Band structure and orbital character of monolayer MoS2 with eleven-band tight-binding model

NASA Astrophysics Data System (ADS)

Shahriari, Majid; Ghalambor Dezfuli, Abdolmohammad; Sabaeian, Mohammad

2018-02-01

In this paper, based on a tight-binding (TB) model, first we present the calculations of eigenvalues as band structure and then present the eigenvectors as probability amplitude for finding electron in atomic orbitals for monolayer MoS2 in the first Brillouin zone. In these calculations we are considering hopping processes between the nearest-neighbor Mo-S, the next nearest-neighbor in-plan Mo-Mo, and the next nearest-neighbor in-plan and out-of-plan S-S atoms in a three-atom based unit cell of two-dimensional rhombic MoS2. The hopping integrals have been solved in terms of Slater-Koster and crystal field parameters. These parameters are calculated by comparing TB model with the density function theory (DFT) in the high-symmetry k-points (i.e. the K- and Γ-points). In our TB model all the 4d Mo orbitals and the 3p S orbitals are considered and detailed analysis of the orbital character of each energy level at the main high-symmetry points of the Brillouin zone is described. In comparison with DFT calculations, our results of TB model show a very good agreement for bands near the Fermi level. However for other bands which are far from the Fermi level, some discrepancies between our TB model and DFT calculations are observed. Upon the accuracy of Slater-Koster and crystal field parameters, on the contrary of DFT, our model provide enough accuracy to calculate all allowed transitions between energy bands that are very crucial for investigating the linear and nonlinear optical properties of monolayer MoS2.

Recombination activity of light-activated copper defects in p-type silicon studied by injection- and temperature-dependent lifetime spectroscopy

NASA Astrophysics Data System (ADS)

Inglese, Alessandro; Lindroos, Jeanette; Vahlman, Henri; Savin, Hele

2016-09-01

The presence of copper contamination is known to cause strong light-induced degradation (Cu-LID) in silicon. In this paper, we parametrize the recombination activity of light-activated copper defects in terms of Shockley—Read—Hall recombination statistics through injection- and temperature dependent lifetime spectroscopy (TDLS) performed on deliberately contaminated float zone silicon wafers. We obtain an accurate fit of the experimental data via two non-interacting energy levels, i.e., a deep recombination center featuring an energy level at Ec-Et=0.48 -0.62 eV with a moderate donor-like capture asymmetry ( k =1.7 -2.6 ) and an additional shallow energy state located at Ec-Et=0.1 -0.2 eV , which mostly affects the carrier lifetime only at high-injection conditions. Besides confirming these defect parameters, TDLS measurements also indicate a power-law temperature dependence of the capture cross sections associated with the deep energy state. Eventually, we compare these results with the available literature data, and we find that the formation of copper precipitates is the probable root cause behind Cu-LID.

Electric train energy consumption modeling

DOE PAGES

Wang, Jinghui; Rakha, Hesham A.

2017-05-01

For this paper we develop an electric train energy consumption modeling framework considering instantaneous regenerative braking efficiency in support of a rail simulation system. The model is calibrated with data from Portland, Oregon using an unconstrained non-linear optimization procedure, and validated using data from Chicago, Illinois by comparing model predictions against the National Transit Database (NTD) estimates. The results demonstrate that regenerative braking efficiency varies as an exponential function of the deceleration level, rather than an average constant as assumed in previous studies. The model predictions are demonstrated to be consistent with the NTD estimates, producing a predicted error ofmore » 1.87% and -2.31%. The paper demonstrates that energy recovery reduces the overall power consumption by 20% for the tested Chicago route. Furthermore, the paper demonstrates that the proposed modeling approach is able to capture energy consumption differences associated with train, route and operational parameters, and thus is applicable for project-level analysis. The model can be easily implemented in traffic simulation software, used in smartphone applications and eco-transit programs given its fast execution time and easy integration in complex frameworks.« less

Electric train energy consumption modeling

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

Wang, Jinghui; Rakha, Hesham A.

For this paper we develop an electric train energy consumption modeling framework considering instantaneous regenerative braking efficiency in support of a rail simulation system. The model is calibrated with data from Portland, Oregon using an unconstrained non-linear optimization procedure, and validated using data from Chicago, Illinois by comparing model predictions against the National Transit Database (NTD) estimates. The results demonstrate that regenerative braking efficiency varies as an exponential function of the deceleration level, rather than an average constant as assumed in previous studies. The model predictions are demonstrated to be consistent with the NTD estimates, producing a predicted error ofmore » 1.87% and -2.31%. The paper demonstrates that energy recovery reduces the overall power consumption by 20% for the tested Chicago route. Furthermore, the paper demonstrates that the proposed modeling approach is able to capture energy consumption differences associated with train, route and operational parameters, and thus is applicable for project-level analysis. The model can be easily implemented in traffic simulation software, used in smartphone applications and eco-transit programs given its fast execution time and easy integration in complex frameworks.« less

Uncertainty of the potential curve minimum for diatomic molecules extrapolated from Dunham type coefficients

NASA Astrophysics Data System (ADS)

Ilieva, T.; Iliev, I.; Pashov, A.

2016-12-01

In the traditional description of electronic states of diatomic molecules by means of molecular constants or Dunham coefficients, one of the important fitting parameters is the value of the zero point energy - the minimum of the potential curve or the energy of the lowest vibrational-rotational level - E00 . Their values are almost always the result of an extrapolation and it may be difficult to estimate their uncertainties, because they are connected not only with the uncertainty of the experimental data, but also with the distribution of experimentally observed energy levels and the particular realization of set of Dunham coefficients. This paper presents a comprehensive analysis based on Monte Carlo simulations, which aims to demonstrate the influence of all these factors on the uncertainty of the extrapolated minimum of the potential energy curve U (Re) and the value of E00 . The very good extrapolation properties of the Dunham coefficients are quantitatively confirmed and it is shown that for a proper estimate of the uncertainties, the ambiguity in the composition of the Dunham coefficients should be taken into account.

Optimal Operation of Energy Storage in Power Transmission and Distribution

NASA Astrophysics Data System (ADS)

Akhavan Hejazi, Seyed Hossein

In this thesis, we investigate optimal operation of energy storage units in power transmission and distribution grids. At transmission level, we investigate the problem where an investor-owned independently-operated energy storage system seeks to offer energy and ancillary services in the day-ahead and real-time markets. We specifically consider the case where a significant portion of the power generated in the grid is from renewable energy resources and there exists significant uncertainty in system operation. In this regard, we formulate a stochastic programming framework to choose optimal energy and reserve bids for the storage units that takes into account the fluctuating nature of the market prices due to the randomness in the renewable power generation availability. At distribution level, we develop a comprehensive data set to model various stochastic factors on power distribution networks, with focus on networks that have high penetration of electric vehicle charging load and distributed renewable generation. Furthermore, we develop a data-driven stochastic model for energy storage operation at distribution level, where the distribution of nodal voltage and line power flow are modelled as stochastic functions of the energy storage unit's charge and discharge schedules. In particular, we develop new closed-form stochastic models for such key operational parameters in the system. Our approach is analytical and allows formulating tractable optimization problems. Yet, it does not involve any restricting assumption on the distribution of random parameters, hence, it results in accurate modeling of uncertainties. By considering the specific characteristics of random variables, such as their statistical dependencies and often irregularly-shaped probability distributions, we propose a non-parametric chance-constrained optimization approach to operate and plan energy storage units in power distribution girds. In the proposed stochastic optimization, we consider uncertainty from various elements, such as solar photovoltaic , electric vehicle chargers, and residential baseloads, in the form of discrete probability functions. In the last part of this thesis we address some other resources and concepts for enhancing the operation of power distribution and transmission systems. In particular, we proposed a new framework to determine the best sites, sizes, and optimal payment incentives under special contracts for committed-type DG projects to offset distribution network investment costs. In this framework, the aim is to allocate DGs such that the profit gained by the distribution company is maximized while each DG unit's individual profit is also taken into account to assure that private DG investment remains economical.

[Oxygen-dependent energy deficit as related to the problems of ontogenetic development disorders and human sociobiological adaptation (theoretical and applied aspects)].

PubMed

Ilyukhina, V A; Kataeva, G V; Korotkov, A D; Chernysheva, E M

2015-01-01

The review states and argues theoretical propositions on the pathogenetic role of pre- and perinatal hypoxic-ischemic brain damage in the formation of sustained oxygen-dependent energy deficit underlying in further ontogenesis the following neurobiological abnormalities: a) a decline in the level of health and compensatory-adaptive capacities of the organism, b) disorders of the psycho-speech development and adaptive behavior in children, c) early development of neuropsychic diseases, g) addition of other types of brain energy metabolism (including glucose metabolism) disorders in chronic polyetiologic diseases young and middle-aged individuals. We highlight and theoretically substantiate the integrated physiological parameters of the oxygen-dependent energy deficit types. We address the features of abnormalities in neuroreflectory and neurohumora regulatory mechanisms of the wakefulness level and its vegetative and hemodynamic provision in different types of energy deficit in children with DSMD, ADHD and school maladjustment. The use of the state-of-the-art neuroimaging techniques significantly increased the possibility of the disintegration of regulatory processes and cognitive functions in children with psycho-speech delays and in a wide range of chronic polyetiologic diseases.

Scanning electron microscope and dye penetration test: comparison of root canal preparation with 15 F CO2 laser microprobe versus conventional method--in vivo study

NASA Astrophysics Data System (ADS)

Kesler, Gavriel; Koren, Rumelia; Kesler, Anat; Hay, Nissim; Gal, Rivka

1999-05-01

The study was conducted on 30 vital maxillary or mandibulary teeth destined for extraction due to periodontal problems. 21 were experimentally treated with pulsed CO2 laser delivered by a newly developed fiber and 9 teeth represented the control group. The micro probe is a flexible, hollow, metal fiber, 300 μm in diameter and 20 mm in length, coupled onto a handpiece, with the following radiation parameters: wavelength-10.6μm pulse duration-50m.sec; energy per pulses 0.25 joule; energy density-360 J/cm2 per pulse; power on tissue-5W. The laser group was divided into three, receiving 20, 40 or 60 pulses, respectively. On light microscopy: in all the control group cases, large amount of residual pulp tissue was seen, it was diminished in some of the low energy group and was totally eradicated in the high energy group. This was confirmed by the scanning electron microscope (SEM) examination. The dentin tubuli were partly occluded with the low energy levels and completely with the high levels, as shown by the high-speed centrifuge dye penetration test and by the SEM tests.

A design of experiments test to define critical spray cleaning parameters for Brulin 815 GD and Jettacin cleaners

NASA Technical Reports Server (NTRS)

Keen, Jill M.; Evans, Kurt B.; Schiffman, Robert L.; Deweese, C. Darrell; Prince, Michael E.

1995-01-01

Experimental design testing was conducted to identify critical parameters of an aqueous spray process intended for cleaning solid rocket motor metal components (steel and aluminum). A two-level, six-parameter, fractional factorial matrix was constructed and conducted for two cleaners, Brulin 815 GD and Diversey Jettacin. The matrix parameters included cleaner temperature and concentration, wash density, wash pressure, rinse pressure, and dishwasher type. Other spray parameters: nozzle stand-off, rinse water temperature, wash and rinse time, dry conditions, and type of rinse water (deionized) were held constant. Matrix response testing utilized discriminating bond specimens (fracture energy and tensile adhesion strength) which represent critical production bond lines. Overall, Jettacin spray cleaning was insensitive to the range of conditions tested for all parameters and exhibited bond strengths significantly above the TCA test baseline for all bond lines tested. Brulin 815 was sensitive to cleaning temperature, but produced bond strengths above the TCA test baseline even at the lower temperatures. Ultimately, the experimental design database was utilized to recommend process parameter settings for future aqueous spray cleaning characterization work.

Accurate calculation and modeling of the adiabatic connection in density functional theory

NASA Astrophysics Data System (ADS)

Teale, A. M.; Coriani, S.; Helgaker, T.

2010-04-01

Using a recently implemented technique for the calculation of the adiabatic connection (AC) of density functional theory (DFT) based on Lieb maximization with respect to the external potential, the AC is studied for atoms and molecules containing up to ten electrons: the helium isoelectronic series, the hydrogen molecule, the beryllium isoelectronic series, the neon atom, and the water molecule. The calculation of AC curves by Lieb maximization at various levels of electronic-structure theory is discussed. For each system, the AC curve is calculated using Hartree-Fock (HF) theory, second-order Møller-Plesset (MP2) theory, coupled-cluster singles-and-doubles (CCSD) theory, and coupled-cluster singles-doubles-perturbative-triples [CCSD(T)] theory, expanding the molecular orbitals and the effective external potential in large Gaussian basis sets. The HF AC curve includes a small correlation-energy contribution in the context of DFT, arising from orbital relaxation as the electron-electron interaction is switched on under the constraint that the wave function is always a single determinant. The MP2 and CCSD AC curves recover the bulk of the dynamical correlation energy and their shapes can be understood in terms of a simple energy model constructed from a consideration of the doubles-energy expression at different interaction strengths. Differentiation of this energy expression with respect to the interaction strength leads to a simple two-parameter doubles model (AC-D) for the AC integrand (and hence the correlation energy of DFT) as a function of the interaction strength. The structure of the triples-energy contribution is considered in a similar fashion, leading to a quadratic model for the triples correction to the AC curve (AC-T). From a consideration of the structure of a two-level configuration-interaction (CI) energy expression of the hydrogen molecule, a simple two-parameter CI model (AC-CI) is proposed to account for the effects of static correlation on the AC. When parametrized in terms of the same input data, the AC-CI model offers improved performance over the corresponding AC-D model, which is shown to be the lowest-order contribution to the AC-CI model. The utility of the accurately calculated AC curves for the analysis of standard density functionals is demonstrated for the BLYP exchange-correlation functional and the interaction-strength-interpolation (ISI) model AC integrand. From the results of this analysis, we investigate the performance of our proposed two-parameter AC-D and AC-CI models when a simple density functional for the AC at infinite interaction strength is employed in place of information at the fully interacting point. The resulting two-parameter correlation functionals offer a qualitatively correct behavior of the AC integrand with much improved accuracy over previous attempts. The AC integrands in the present work are recommended as a basis for further work, generating functionals that avoid spurious error cancellations between exchange and correlation energies and give good accuracy for the range of densities and types of correlation contained in the systems studied here.

Energy conditions in f (T, TG) gravity

NASA Astrophysics Data System (ADS)

Jawad, Abdul

2015-05-01

This paper is devoted to study the energy conditions in f( T, T G ) gravity for the FRW universe with perfect fluid, where T is the torsion scalar and T G is the quartic torsion scalar. We construct the energy conditions in this theory and discuss them for two specific f( T, T G ) models. These models are and , which represent viability through some cosmological scenarios. We consider cosmographic parameters to simplify the energy condition expressions. The present-day values of these parameters are assumed to check the constraints on model parameters through energy condition inequalities.

Design and characterization of textured surfaces for applications in the food industry

NASA Astrophysics Data System (ADS)

Lazzini, G.; Romoli, L.; Blunt, L.; Gemini, L.

2017-12-01

The aim of this work is to design, manufacture and characterize surface morphologies on AISI 316L stainless steel produced by a custom designed laser-texturing strategy. Surface textures were characterized at a micrometric dimension in terms of areal parameters compliant with ISO 25178, and correlations between these parameters and processing parameters (e.g. laser energy dose supplied to the material, repetition rate of the laser pulses and scanning velocity) were investigated. Preliminary efforts were devoted to the research of special requirements for surface morphology that, according to the commonly accepted research on the influence of surface roughness on cellular adhesion on surfaces, should discourage the formation of biofilms. The topographical characterization of the surfaces was performed with a coherence scanning interferometer. This approach showed that increasing doses of energy to the surfaces increased the global level of roughness as well as the surface complexity. Moreover, the behavior of the parameters S pk, S vk also indicates that, due to the ablation process, an increase in the energy dose causes an average increase in the height of the highest peaks and in the depth of the deepest dales. The study of the density of peaks S pd showed that none of the surfaces analyzed here seem to perfectly match the conditions dictated by the theories on cellular adhesion to confer anti-biofouling properties. However, this result seems to be mainly due to the limits of the resolving power of coherence scanning interferometry, which does not allow the resolution of sub-micrometric features which could be crucial in the prevention of cellular attachment.

The electron trap parameter extraction-based investigation of the relationship between charge trapping and activation energy in IGZO TFTs under positive bias temperature stress

NASA Astrophysics Data System (ADS)

Rhee, Jihyun; Choi, Sungju; Kang, Hara; Kim, Jae-Young; Ko, Daehyun; Ahn, Geumho; Jung, Haesun; Choi, Sung-Jin; Myong Kim, Dong; Kim, Dae Hwan

2018-02-01

Experimental extraction of the electron trap parameters which are associated with charge trapping into gate insulators under the positive bias temperature stress (PBTS) is proposed and demonstrated for the first time in amorphous indium-gallium-zinc-oxide thin-film transistors. This was done by combining the PBTS/recovery time-evolution of the experimentally decomposed threshold voltage shift (ΔVT) and the technology computer-aided design (TCAD)-based charge trapping simulation. The extracted parameters were the trap density (NOT) = 2.6 × 1018 cm-3, the trap energy level (ΔET) = 0.6 eV, and the capture cross section (σ0) = 3 × 10-19 cm2. Furthermore, based on the established TCAD framework, the relationship between the electron trap parameters and the activation energy (Ea) is comprehensively investigated. It is found that Ea increases with an increase in σ0, whereas Ea is independent of NOT. In addition, as ΔET increases, Ea decreases in the electron trapping-dominant regime (low ΔET) and increases again in the Poole-Frenkel (PF) emission/hopping-dominant regime (high ΔET). Moreover, our results suggest that the cross-over ΔET point originates from the complicated temperature-dependent competition between the capture rate and the emission rate. The PBTS bias dependence of the relationship between Ea and ΔET suggests that the electric field dependence of the PF emission-based electron hopping is stronger than that of the thermionic field emission-based electron trapping.

Gyrokinetic simulations and experiment

NASA Astrophysics Data System (ADS)

Ross, David W.; Bravenec, R. V.; Dorland, W.

2002-11-01

Nonlinear gyrokinetic simulations with the code GS2 have been carried out in an effort to predict transport fluxes and fluctuation levels in the tokamaks DIII-D and Alcator C-Mod.(W. Dorland et al. in Fusion Energy 2000 (International Atomic Energy Agency, Vienna, 2000).)^,( W. Ross and W. Dorland, submitted to Phys. Plasmas (2002).) These simulations account for full electron dynamics and, in some instances, electromagnetic waves.( D. W. Ross, W. Dorland, and B. N. Rogers, Bull. Am. Phys. Soc. 46, 115 (2001).) Here, some issues of the necessary resolution, precision and wave number range are examined in connection with the experimental comparisons and parameter scans.

Efficient quantum state transfer in an engineered chain of quantum bits

NASA Astrophysics Data System (ADS)

Sandberg, Martin; Knill, Emanuel; Kapit, Eliot; Vissers, Michael R.; Pappas, David P.

2016-03-01

We present a method of performing quantum state transfer in a chain of superconducting quantum bits. Our protocol is based on engineering the energy levels of the qubits in the chain and tuning them all simultaneously with an external flux bias. The system is designed to allow sequential adiabatic state transfers, resulting in on-demand quantum state transfer from one end of the chain to the other. Numerical simulations of the master equation using realistic parameters for capacitive nearest-neighbor coupling, energy relaxation, and dephasing show that fast, high-fidelity state transfer should be feasible using this method.

Decreased energy demanding processes in the frontal lobes of schizophrenics due to neuroleptics? A 31P-magneto-resonance spectroscopic study.

PubMed

Volz, H P; Rzanny, R; Rössger, G; Hübner, G; Kreitschmann-Andermahr, I; Kaiser, W A; Sauer, H

1997-12-30

In the present investigation on 31P-magneto-resonance spectroscopic parameters in the frontal lobe, we found phosphocreatine levels and the ratio phosphocreatine/adenosine triphosphate to be increased (12.62 +/- 1.98% resp. 0.31 +/- 0.06) in 50 neuroleptic-treated schizophrenics, whereas no differences were detected in 10 neuroleptic-free patients (11.66 +/- 2.57% resp. 0.29 +/- 0.08) compared to 36 controls (11.37 +/- 1.45 resp. 0.29 +/- 0.04). This result points to a major role of neuroleptics in the metabolism of high-energy phosphates.

NEW Fe IX LINE IDENTIFICATIONS USING SOLAR AND HELIOSPHERIC OBSERVATORY/SOLAR ULTRAVIOLET MEASUREMENT OF EMITTED RADIATION AND HINODE/EIS JOINT OBSERVATIONS OF THE QUIET SUN

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

Landi, E.; Young, P. R.

2009-12-20

In this work, we study joint observations of Hinode/EUV Imaging Spectrometer (EIS) and Solar and Heliospheric Observatory/Solar Ultraviolet Measurement of Emitted Radiation of Fe IX lines emitted by the same level of the high energy configuration 3s {sup 2}3p {sup 5}4p. The intensity ratios of these lines are dependent on atomic physics parameters only and not on the physical parameters of the emitting plasma, so that they are excellent tools to verify the relative intensity calibration of high-resolution spectrometers that work in the 170-200 A and 700-850 A wavelength ranges. We carry out extensive atomic physics calculations to improve themore » accuracy of the predicted intensity ratio, and compare the results with simultaneous EIS-SUMER observations of an off-disk quiet Sun region. We were able to identify two ultraviolet lines in the SUMER spectrum that are emitted by the same level that emits one bright line in the EIS wavelength range. Comparison between predicted and measured intensity ratios, wavelengths and energy separation of Fe IX levels confirms the identifications we make. Blending and calibration uncertainties are discussed. The results of this work are important for cross-calibrating EIS and SUMER, as well as future instrumentation.« less

Dynamic and energetic characteristics of a bistable piezoelectric vibration energy harvester with an elastic magnifier

NASA Astrophysics Data System (ADS)

Wang, Guangqing; Liao, Wei-Hsin; Yang, Binqiang; Wang, Xuebao; Xu, Wentan; Li, Xiuling

2018-05-01

Bistable piezoelectric energy harvesters are being increasingly seen as an alternative to batteries in low-power devices. However, their energy harvesting characteristics are limited. To enhance these, we use a configuration including an elastic magnifier to amplify base excitation and provide sufficient kinetic energy to overcome potential well barriers, thus leading to large-amplitude bistable motion. We derive the distributed parameter mathematical model of this configuration by using Hamilton's principle. We then investigate the nonlinear dynamic behaviors and energetic characteristics and analyze the bifurcation for the equilibrium solution of the model. The simulations and experiments show high electromechanical responses and energy generation characteristics of the proposed system over a broad frequency band. The results suggest that, compared with a typical bistable piezoelectric energy harvester, the proposed energy harvester system with an elastic magnifier can provide higher output over a broader frequency band at lower excitation levels by adjusting the system's mass and stiffness ratios.

Renormalization group method based on the ionization energy theory

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

Arulsamy, Andrew Das, E-mail: sadwerdna@gmail.com; School of Physics, University of Sydney, Sydney, New South Wales 2006

2011-03-15

Proofs are developed to explicitly show that the ionization energy theory is a renormalized theory, which mathematically exactly satisfies the renormalization group formalisms developed by Gell-Mann-Low, Shankar and Zinn-Justin. However, the cutoff parameter for the ionization energy theory relies on the energy-level spacing, instead of lattice point spacing in k-space. Subsequently, we apply the earlier proofs to prove that the mathematical structure of the ionization-energy dressed electron-electron screened Coulomb potential is exactly the same as the ionization-energy dressed electron-phonon interaction potential. The latter proof is proven by means of the second-order time-independent perturbation theory with the heavier effective mass condition,more » as required by the electron-electron screened Coulomb potential. The outcome of this proof is that we can derive the heat capacity and the Debye frequency as a function of ionization energy, which can be applied in strongly correlated matter and nanostructures.« less

Wastewater treatment high rate algal ponds (WWT HRAP) for low-cost biofuel production.

PubMed

Mehrabadi, Abbas; Craggs, Rupert; Farid, Mohammed M

2015-05-01

Growing energy demand and water consumption have increased concerns about energy security and efficient wastewater treatment and reuse. Wastewater treatment high rate algal ponds (WWT HRAPs) are a promising technology that could help solve these challenges concurrently where climate is favorable. WWT HRAPs have great potential for biofuel production as a by-product of WWT, since the costs of algal cultivation and harvest for biofuel production are covered by the wastewater treatment function. Generally, 800-1400 GJ/ha/year energy (average biomass energy content: 20 GJ/ton; HRAP biomass productivity: 40-70 tons/ha/year) can be produced in the form of harvestable biomass from WWT HRAP which can be used to provide community-level energy supply. In this paper the benefits of WWT HRAPs are compared with conventional mass algal culture systems. Moreover, parameters to effectively increase algal energy content and overall energy production from WWT HRAP are discussed including selection of appropriate algal biomass biofuel conversion pathways. Copyright © 2014 Elsevier Ltd. All rights reserved.

Using Multistate Reweighting to Rapidly and Efficiently Explore Molecular Simulation Parameters Space for Nonbonded Interactions.

PubMed

Paliwal, Himanshu; Shirts, Michael R

2013-11-12

Multistate reweighting methods such as the multistate Bennett acceptance ratio (MBAR) can predict free energies and expectation values of thermodynamic observables at poorly sampled or unsampled thermodynamic states using simulations performed at only a few sampled states combined with single point energy reevaluations of these samples at the unsampled states. In this study, we demonstrate the power of this general reweighting formalism by exploring the effect of simulation parameters controlling Coulomb and Lennard-Jones cutoffs on free energy calculations and other observables. Using multistate reweighting, we can quickly identify, with very high sensitivity, the computationally least expensive nonbonded parameters required to obtain a specified accuracy in observables compared to the answer obtained using an expensive "gold standard" set of parameters. We specifically examine free energy estimates of three molecular transformations in a benchmark molecular set as well as the enthalpy of vaporization of TIP3P. The results demonstrates the power of this multistate reweighting approach for measuring changes in free energy differences or other estimators with respect to simulation or model parameters with very high precision and/or very low computational effort. The results also help to identify which simulation parameters affect free energy calculations and provide guidance to determine which simulation parameters are both appropriate and computationally efficient in general.

Modulation of plasma N-acylethanolamine levels and physiological parameters by dietary fatty acid composition in humans

PubMed Central

Jones, Peter J. H.; Lin, Lin; Gillingham, Leah G.; Yang, Haifeng; Omar, Jaclyn M.

2014-01-01

N-acylethanolamines (NAEs) are endogenous lipid-signaling molecules involved in satiety and energetics; however, how diet impacts circulating NAE concentrations and their downstream metabolic actions in humans remains unknown. Objectives were to examine effects of diets enriched with high-oleic canola oil (HOCO) or HOCO blended with flaxseed oil (FXCO), compared with a Western diet (WD), on plasma NAE levels and the association with energy expenditure and substrate oxidation. Using a randomized controlled crossover design, 36 hypercholesterolemic participants consumed three isoenergetic diets for 28 days, each containing 36% energy from fat, of which 70% was HOCO, FXCO, or WD. Ultra-performance liquid chromatography-MS/MS was used to measure plasma NAE levels and indirect calorimetry to assess energy expenditure and substrate oxidation. After 28 days, compared with WD, plasma oleoylethanolamide (OEA) and alpha-linolenoyl ethanolamide (ALEA) levels were significantly increased in response to HOCO and FXCO (P = 0.002, P < 0.001), respectively. Correlation analysis demonstrated an inverse association between plasma OEA levels and percent body fat (r = −0.21, P = 0.04), and a positive association was observed between the plasma arachidonoyl ethanolamide (AEA)/OEA ratio and android:gynoid fat (r = 0.23, P = 0.02), respectively. Results suggest that plasma NAE levels are upregulated via their dietary lipid substrates and may modulate regional and total fat mass through lipid-signaling mechanisms. PMID:25262934

Estimation of turbulent kinetic energy using 4D phase-contrast MRI: Effect of scan parameters and target vessel size.

PubMed

Ha, Hojin; Hwang, Dongha; Kim, Guk Bae; Kweon, Jihoon; Lee, Sang Joon; Baek, Jehyun; Kim, Young-Hak; Kim, Namkug; Yang, Dong Hyun

2016-07-01

Quantifying turbulence velocity fluctuation is important because it indicates the fluid energy dissipation of the blood flow, which is closely related to the pressure drop along the blood vessel. This study aims to evaluate the effects of scan parameters and the target vessel size of 4D phase-contrast (PC)-MRI on quantification of turbulent kinetic energy (TKE). Comprehensive 4D PC-MRI measurements with various velocity-encoding (VENC), echo time (TE), and voxel size values were carried out to estimate TKE distribution in stenotic flow. The total TKE (TKEsum), maximum TKE (TKEmax), and background noise level (TKEnoise) were compared for each scan parameter. The feasibility of TKE estimation in small vessels was also investigated. Results show that the optimum VENC for stenotic flow with a peak velocity of 125cm/s was 70cm/s. Higher VENC values overestimated the TKEsum by up to six-fold due to increased TKEnoise, whereas lower VENC values (30cm/s) underestimated it by 57.1%. TE and voxel size did not significantly influence the TKEsum and TKEnoise, although the TKEmax significantly increased as the voxel size increased. TKE quantification in small-sized vessels (3-5-mm diameter) was feasible unless high-velocity turbulence caused severe phase dispersion in the reference image. Copyright © 2016 Elsevier Inc. All rights reserved.

Relativistic excited state binding energies and RMS radii of Λ-hypernuclei

NASA Astrophysics Data System (ADS)

Nejad, S. Mohammad Moosavi; Armat, A.

2018-02-01

Using an analytical solution for the relativistic equation of single Λ-hypernuclei in the presence of Woods-Saxon (WS) potential we present, for the first time, an analytical form for the excited state binding energies of 1p, 1d, 1f and 1g shells of a number of hypernuclei. Based on phenomenological analysis of the Λ binding energies in a set of Λ-hypernuclei, the WS potential parameters are obtained phenomenologically for the set of Λ-hypernuclei. Systematic study of the energy levels of single Λ-hypernuclei enables us to extract more detailed information about the Λ-nucleon interaction. We also study the root mean square (RMS) radii of the Λ orbits in the hypernuclear ground states. Our results are presented for several hypernuclei and it is shown that our results for the binding energies are in good agreement with experimental data.

Constraints on the holographic dark energy model via type Ia supernovae, baryon acoustic oscillation, and WMAP7

NASA Astrophysics Data System (ADS)

Xu, Lixin

2012-06-01

In this paper, the holographic dark energy model, where the future event horizon is taken as an IR cutoff, is confronted by using currently available cosmic observational data sets which include type Ia supernovae, baryon acoustic oscillation, and cosmic microwave background radiation from full information of WMAP 7-yr data. Via the Markov chain Monte Carlo method, we obtain the values of model parameter c=0.696-0.0737-0.132-0.190+0.0736+0.159+0.264 with 1, 2, 3σ regions. Therefore, one can conclude that at at least 3σ level the future Universe will be dominated by phantom-like dark energy. It is not consistent with positive energy condition, however this condition must be satisfied to derive the holographic bound. It implies that the current cosmic observational data points disfavor the holographic dark energy model.

Modeling of electrohydrodynamic drying process using response surface methodology

PubMed Central

Dalvand, Mohammad Jafar; Mohtasebi, Seyed Saeid; Rafiee, Shahin

2014-01-01

Energy consumption index is one of the most important criteria for judging about new, and emerging drying technologies. One of such novel and promising alternative of drying process is called electrohydrodynamic (EHD) drying. In this work, a solar energy was used to maintain required energy of EHD drying process. Moreover, response surface methodology (RSM) was used to build a predictive model in order to investigate the combined effects of independent variables such as applied voltage, field strength, number of discharge electrode (needle), and air velocity on moisture ratio, energy efficiency, and energy consumption as responses of EHD drying process. Three-levels and four-factor Box–Behnken design was employed to evaluate the effects of independent variables on system responses. A stepwise approach was followed to build up a model that can map the entire response surface. The interior relationships between parameters were well defined by RSM. PMID:24936289

Characterization of turbulence stability through the identification of multifractional Brownian motions

NASA Astrophysics Data System (ADS)

Lee, K. C.

2013-02-01

Multifractional Brownian motions have become popular as flexible models in describing real-life signals of high-frequency features in geoscience, microeconomics, and turbulence, to name a few. The time-changing Hurst exponent, which describes regularity levels depending on time measurements, and variance, which relates to an energy level, are two parameters that characterize multifractional Brownian motions. This research suggests a combined method of estimating the time-changing Hurst exponent and variance using the local variation of sampled paths of signals. The method consists of two phases: initially estimating global variance and then accurately estimating the time-changing Hurst exponent. A simulation study shows its performance in estimation of the parameters. The proposed method is applied to characterization of atmospheric stability in which descriptive statistics from the estimated time-changing Hurst exponent and variance classify stable atmosphere flows from unstable ones.

Deviation from Boltzmann distribution in excited energy levels of singly-ionized iron in an argon glow discharge plasma for atomic emission spectrometry

NASA Astrophysics Data System (ADS)

Zhang, Lei; Kashiwakura, Shunsuke; Wagatsuma, Kazuaki

2012-01-01

A Boltzmann plot for many iron ionic lines having excitation energies of 4.7-9.1 eV was investigated in an argon glow discharge plasma when the discharge parameters, such as the voltage/current and the gas pressure, were varied. A Grimm-style radiation source was employed in a DC voltage range of 400-800 V at argon pressures of 400-930 Pa. The plot did not follow a linear relationship over a wide range of the excitation energy, but it yielded a normal Boltzmann distribution in the range of 4.7-5.8 eV and a large overpopulation in higher-lying excitation levels of iron ion. A probable reason for this phenomenon is that excitations for higher excited energy levels of iron ion would be predominantly caused by non-thermal collisions with argon species, the internal energy of which is received by iron atoms for the ionization. Particular intense ionic lines, which gave a maximum peak of the Boltzmann plot, were observed at an excitation energy of ca. 7.7 eV. They were the Fe II 257.297-nm and the Fe II 258.111-nm lines, derived from the 3d54s4p 6P excited levels. The 3d54s4p 6P excited levels can be highly populated through a resonance charge transfer from the ground state of argon ion, because of good matching in the excitation energy as well as the conservation of the total spin before and after the collision. An enhancement factor of the emission intensity for various Fe II lines could be obtained from a deviation from the normal Boltzmann plot, which comprised the emission lines of 4.7-5.8 eV. It would roughly correspond to a contribution of the charge transfer excitation to the excited levels of iron ion, suggesting that the charge-transfer collision could elevate the number density of the corresponding excited levels by a factor of ca.104. The Boltzmann plots give important information on the reason why a variety of iron ionic lines can be emitted from glow discharge plasmas.

Comparison of Degrees of Potential-Energy-Surface Anharmonicity for Complexes and Clusters with Hydrogen Bonds

NASA Astrophysics Data System (ADS)

Kozlovskaya, E. N.; Doroshenko, I. Yu.; Pogorelov, V. E.; Vaskivskyi, Ye. V.; Pitsevich, G. A.

2018-01-01

Previously calculated multidimensional potential-energy surfaces of the MeOH monomer and dimer, water dimer, malonaldehyde, formic acid dimer, free pyridine-N-oxide/trichloroacetic acid complex, and protonated water dimer were analyzed. The corresponding harmonic potential-energy surfaces near the global minima were constructed for series of clusters and complexes with hydrogen bonds of different strengths based on the behavior of the calculated multidimensional potential-energy surfaces. This enabled the introduction of an obvious anharmonicity parameter for the calculated potential-energy surfaces. The anharmonicity parameter was analyzed as functions of the size of the analyzed area near the energy minimum, the number of points over which energies were compared, and the dimensionality of the solved vibrational problem. Anharmonicity parameters for potential-energy surfaces in complexes with strong, medium, and weak H-bonds were calculated under identical conditions. The obtained anharmonicity parameters were compared with the corresponding diagonal anharmonicity constants for stretching vibrations of the bridging protons and the lengths of the hydrogen bridges.

Calibrating Physical Parameters in House Models Using Aggregate AC Power Demand

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

Sun, Yannan; Stevens, Andrew J.; Lian, Jianming

For residential houses, the air conditioning (AC) units are one of the major resources that can provide significant flexibility in energy use for the purpose of demand response. To quantify the flexibility, the characteristics of all the houses need to be accurately estimated, so that certain house models can be used to predict the dynamics of the house temperatures in order to adjust the setpoints accordingly to provide demand response while maintaining the same comfort levels. In this paper, we propose an approach using the Reverse Monte Carlo modeling method and aggregate house models to calibrate the distribution parameters ofmore » the house models for a population of residential houses. Given the aggregate AC power demand for the population, the approach can successfully estimate the distribution parameters for the sensitive physical parameters based on our previous uncertainty quantification study, such as the mean of the floor areas of the houses.« less

Triple coupling and parameter resonance in quantum optomechanics with a single atom

NASA Astrophysics Data System (ADS)

Chang, Yue; Ian, H.; Sun, C. P.

2009-11-01

We study the energy level structure and quantum dynamics for a cavity optomechanical system assisted by a single atom. It is found that a triple coupling involving a photon, a phonon and an atom cannot be described only by the quasi-orbital angular momentum at frequency resonance, there also exists the phenomenon of parameter resonance, namely, when the system parameters are matched in some way, the evolution of the end mirror of the cavity is conditioned by the dressed states of the photon-atom subsystem. The quantum decoherence due to this conditional dynamics is studied in detail. In the quasi-classical limit of very large angular momentum, this system will behave like a standard cavity-QED system described by the Jaynes-Cummings (J-C) model when the angular momentum operators are transformed to bosonic operators of a single mode. We test this observation with an experimentally accessible parameter.

Research on Matching Method of Power Supply Parameters for Dual Energy Source Electric Vehicles

NASA Astrophysics Data System (ADS)

Jiang, Q.; Luo, M. J.; Zhang, S. K.; Liao, M. W.

2018-03-01

A new type of power source is proposed, which is based on the traffic signal matching method of the dual energy source power supply composed of the batteries and the supercapacitors. First, analyzing the power characteristics is required to meet the excellent dynamic characteristics of EV, studying the energy characteristics is required to meet the mileage requirements and researching the physical boundary characteristics is required to meet the physical conditions of the power supply. Secondly, the parameter matching design with the highest energy efficiency is adopted to select the optimal parameter group with the method of matching deviation. Finally, the simulation analysis of the vehicle is carried out in MATLABSimulink, The mileage and energy efficiency of dual energy sources are analyzed in different parameter models, and the rationality of the matching method is verified.

The stationary points and structure of high-energy scattering amplitude

NASA Astrophysics Data System (ADS)

Samokhin, A. P.; Petrov, V. A.

2018-06-01

The ISR and the 7 TeV LHC data indicate that the differential cross-section of elastic proton-proton scattering remains almost energy-independent at the transferred momentum t ≈ - 0.21GeV2 at the level of ≈ 7.5 mb /GeV2. This property of dσ / dt (the "first" stationary point) appears due to the correlated growth of the total cross-section and the local slope parameter and can be expressed as a relation between the latter quantities. We anticipate that this property will be true up to 13 TeV. This enables us to normalize the preliminary TOTEM data for dσ / dt at 13 TeV and 0.05 < | t | < 3.4GeV2 and predict the values of dσ / dt at this energy. These data give an evidence of the second stationary point at t ≈ - 2.3GeV2 at the level of ≈ 33 nb /GeV2. The energy evolution of dσ / dt looks as if the high energy elastic scattering amplitude is a sum of two similar terms. We argue that the existence of the two stationary points and the two-component structure of the high energy elastic scattering amplitude are general properties for all elastic processes.

Energy Performance Assessment of Radiant Cooling System through Modeling and Calibration at Component Level

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

Khan, Yasin; Mathur, Jyotirmay; Bhandari, Mahabir S

2016-01-01

The paper describes a case study of an information technology office building with a radiant cooling system and a conventional variable air volume (VAV) system installed side by side so that performancecan be compared. First, a 3D model of the building involving architecture, occupancy, and HVAC operation was developed in EnergyPlus, a simulation tool. Second, a different calibration methodology was applied to develop the base case for assessing the energy saving potential. This paper details the calibration of the whole building energy model to the component level, including lighting, equipment, and HVAC components such as chillers, pumps, cooling towers, fans,more » etc. Also a new methodology for the systematic selection of influence parameter has been developed for the calibration of a simulated model which requires large time for the execution. The error at the whole building level [measured in mean bias error (MBE)] is 0.2%, and the coefficient of variation of root mean square error (CvRMSE) is 3.2%. The total errors in HVAC at the hourly are MBE = 8.7% and CvRMSE = 23.9%, which meet the criteria of ASHRAE 14 (2002) for hourly calibration. Different suggestions have been pointed out to generalize the energy saving of radiant cooling system through the existing building system. So a base case model was developed by using the calibrated model for quantifying the energy saving potential of the radiant cooling system. It was found that a base case radiant cooling system integrated with DOAS can save 28% energy compared with the conventional VAV system.« less

New analytical model for the ozone electronic ground state potential surface and accurate ab initio vibrational predictions at high energy range.

PubMed

Tyuterev, Vladimir G; Kochanov, Roman V; Tashkun, Sergey A; Holka, Filip; Szalay, Péter G

2013-10-07

An accurate description of the complicated shape of the potential energy surface (PES) and that of the highly excited vibration states is of crucial importance for various unsolved issues in the spectroscopy and dynamics of ozone and remains a challenge for the theory. In this work a new analytical representation is proposed for the PES of the ground electronic state of the ozone molecule in the range covering the main potential well and the transition state towards the dissociation. This model accounts for particular features specific to the ozone PES for large variations of nuclear displacements along the minimum energy path. The impact of the shape of the PES near the transition state (existence of the "reef structure") on vibration energy levels was studied for the first time. The major purpose of this work was to provide accurate theoretical predictions for ozone vibrational band centres at the energy range near the dissociation threshold, which would be helpful for understanding the very complicated high-resolution spectra and its analyses currently in progress. Extended ab initio electronic structure calculations were carried out enabling the determination of the parameters of a minimum energy path PES model resulting in a new set of theoretical vibrational levels of ozone. A comparison with recent high-resolution spectroscopic data on the vibrational levels gives the root-mean-square deviations below 1 cm(-1) for ozone band centres up to 90% of the dissociation energy. New ab initio vibrational predictions represent a significant improvement with respect to all previously available calculations.

Spectroscopic properties and energy transfer parameters of Er3+-doped fluorozirconate and oxyfluoroaluminate glasses.

PubMed

Huang, Feifei; Liu, Xueqiang; Hu, Lili; Chen, Danping

2014-05-23

Er3+-doped fluorozirconate (ZrF4-BaF2-YF3-AlF3) and oxyfluoroaluminate glasses are successfully prepared here. These glasses exhibit significant superiority compared with traditional fluorozirconate glass (ZrF4-BaF2-LaF3-AlF3-NaF) because of their higher temperature of glass transition and better resistance to water corrosion. Judd-Ofelt (J-O) intensity parameters are evaluated and used to compute the radiative properties based on the VIS-NIR absorption spectra. Broad emission bands located at 1535 and 2708 nm are observed, and large calculated emission sections are obtained. The intensity of 2708 nm emission closely relates to the phonon energy of host glass. A lower phonon energy leads to a more intensive 2708 nm emission. The energy transfer processes of Er3+ ions are discussed and lifetime of Er3+:4I13/2 is measured. It is the first time to observe that a longer lifetime of the 4I13/2 level leads to a less intensive 1535 nm emission, because the lifetime is long enough to generate excited state absorption (ESA) and energy transfer (ET) processes. These results indicate that the novel glasses possess better chemical and thermal properties as well as excellent optical properties compared with ZBLAN glass. These Er3+-doped ZBYA and oxyfluoroaluminate glasses have potential applications as laser materials.

Evaluation of Cyavanaprāśa on Health and Immunity related Parameters in Healthy Children: A Two Arm, Randomized, Open Labeled, Prospective, Multicenter, Clinical Study.

PubMed

Gupta, Arun; Kumar, Sunil; Dole, Sanjeeva; Deshpande, Shailesh; Deshpande, Vaishali; Singh, Sudha; Sasibhushan, V

2017-01-01

Cyavanaprāśa (CP) is an Ayurvedic immune booster formulation that confers vigor and vitality while delaying the ageing process. Benefits of CP have been studied widely in adult population. Current study assessed beneficial effects of CP on health and immunity related parameters in healthy children. This study was a 6 month long two armed, randomized, open labeled, prospective clinical study. School going healthy children between ages of 5-12 years were randomized to receive orally daily either CP (approx. 6 g) followed by a cup of milk (100 - 200 ml) or cup of milk only twice a day while continuing with their normal/routine diet. Results were analyzed based on number of episodes, severity, duration of illness (infections and allergies) and number of absent days due to illness during the study duration and changes in levels of energy, physical fitness, strength, stamina and quality of life in children which were recorded in subject diary by their parents/Legally Acceptable Representative (LAR). 702 participants were randomized, out of which 627 completed the study (CP n = 313; Control n = 314). Results of immunity (episodes of infections or allergy related conditions) showed more than 2 times protection from immunity related illness in CP Group as compared to the control. CP also showed better percentage improvement in energy levels, physical fitness, strength, stamina and quality of life assessed through KIDSCREEN QOL-27 questionnaires in children. Regular consumption of CP for a period of six months could significantly improve immunity, energy levels, physical fitness, strength, stamina and quality of life in school going healthy children. Clinical Trail Registry of India vide CTRI/2015/02/005574, Dated 24 February 2015.

Evaluation of Cyavanaprāśa on Health and Immunity related Parameters in Healthy Children: A Two Arm, Randomized, Open Labeled, Prospective, Multicenter, Clinical Study

PubMed Central

Gupta, Arun; Kumar, Sunil; Dole, Sanjeeva; Deshpande, Shailesh; Deshpande, Vaishali; Singh, Sudha; Sasibhushan, V.

2017-01-01

Context: Cyavanaprāśa (CP) is an Ayurvedic immune booster formulation that confers vigor and vitality while delaying the ageing process. Benefits of CP have been studied widely in adult population. Objectives: Current study assessed beneficial effects of CP on health and immunity related parameters in healthy children. Methods: This study was a 6 month long two armed, randomized, open labeled, prospective clinical study. School going healthy children between ages of 5-12 years were randomized to receive orally daily either CP (approx. 6 g) followed by a cup of milk (100 – 200 ml) or cup of milk only twice a day while continuing with their normal/routine diet. Results were analyzed based on number of episodes, severity, duration of illness (infections and allergies) and number of absent days due to illness during the study duration and changes in levels of energy, physical fitness, strength, stamina and quality of life in children which were recorded in subject diary by their parents/Legally Acceptable Representative (LAR). Results: 702 participants were randomized, out of which 627 completed the study (CP n = 313; Control n = 314). Results of immunity (episodes of infections or allergy related conditions) showed more than 2 times protection from immunity related illness in CP Group as compared to the control. CP also showed better percentage improvement in energy levels, physical fitness, strength, stamina and quality of life assessed through KIDSCREEN QOL-27 questionnaires in children. Conclusion: Regular consumption of CP for a period of six months could significantly improve immunity, energy levels, physical fitness, strength, stamina and quality of life in school going healthy children. Study Registration: Clinical Trail Registry of India vide CTRI/2015/02/005574, Dated 24 February 2015. PMID:28867858

Nonlinear analysis and characteristics of inductive galloping energy harvesters

NASA Astrophysics Data System (ADS)

Dai, H. L.; Yang, Y. W.; Abdelkefi, A.; Wang, L.

2018-06-01

This paper presents an investigation on analysis and characteristics of aerodynamic electromagnetic energy harvesters. The source of aeroelastic oscillations results from galloping of a prismatic structure. A nonlinear distributed-parameter model is developed representing the dynamics of the transverse degree of freedom and the electric current induced in the coil. Firstly, we perform a linear analysis to study the impacts of the external electrical resistance, magnet placement, electromagnetic coupling coefficient, and internal resistance in the coil on the cut-in speed of instability of the coupled electroaeroelastic system. It is demonstrated that these parameters have significant impacts on cut-in speed of instability of the harvester system. Subsequently, a nonlinear analysis is implemented to explore the influences of these parameters on the output property of the energy harvester. The results show that there exists an optimal external electrical resistance which maximizes the output power of the harvester, and this optimal value varies with the magnet's placement, wind speed, electromagnetic coupling coefficient and internal resistance of the coil. It is also demonstrated that an increase in the distance between the clamped end and the magnet, an increase in the electromagnetic coupling coefficient, and/or a decrease in the internal resistance of the coil are accompanied by an increase in the level of the harvested power and a decrease in the tip displacement of the bluff body which is associated with a resistive-shunt damping effect in the harvester. The implemented studies give a constructive guidance to design and enhance the output performance of aerodynamic electromagnetic energy harvesters.

Mesoscopic structure formation in condensed matter due to vacuum fluctuations

NASA Astrophysics Data System (ADS)

Sen, Siddhartha; Gupta, Kumar S.; Coey, J. M. D.

2015-10-01

An observable influence of zero-point fluctuations of the vacuum electromagnetic field on bound electrons is well known in the hydrogen atom, where it produces the Lamb shift. Here, we adapt an approach used to explain the Lamb shift in terms of a slight expansion of the orbits due to interaction with the zero-point field and apply it to assemblies of N electrons that are modeled as independent atomically bound two-level systems. The effect is to stabilize a collective ground-state energy, which leads to a prediction of novel effects at room temperature for quasi-two-dimensional systems over a range of parameters in the model, namely, N , the two-level excitation energy ℏ ω and the ionization energy ℏ ω +ɛ . Some mesoscopic systems where these effects may be observable include water sheaths on protein or DNA, surfaces of gaseous nanobubbles, and the magnetic response of inhomogeneous, electronically dilute oxides. No such effects are envisaged for uniform three-dimensional systems.

Ab initio study on the ground and low-lying states of BAlk (Alk = Li, Na, K) molecules.

PubMed

Xiao, Ke-La; Yang, Chuan-Lu; Wang, Mei-Shan; Ma, Xiao-Guang; Liu, Wen-Wang

2014-10-02

The potential energy curves (PECs) and dipole moment functions of (1)Π, (3)Π, (1)Σ(+), and (3)Σ(+) states of BAlk (Alk = Li, Na, K) are calculated using multireference configuration interaction method and large all-electron basis sets. The effects of inner-shell correlation electron for BAlk are considered. The ro-vibrational energy levels are obtained by solving the Schrödinger equation of nuclear motion based on the ab initio PECs. The spectroscopic parameters are determined from the ro-vibrational levels with Dunham expansion. The PECs are fitted into analytical potential energy functions using the Morse long-range potential function. The dipole moment functions for the states of BAlk are presented. The transition dipole moments for (1)Σ(+) → (1)Π and (3)Σ(+) → (3)Π states of BAlk are obtained. The interactions between the outermost electron of Alk and B 2p electrons for (1)Π, (3)Π, (1)Σ(+), and (3)Σ(+) states are also analyzed, respectively.