Dirac Particle for the Position Dependent Mass in the Generalized Asymmetric Woods-Saxon Potential
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Soner Alpdoğan
2014-01-01
Full Text Available The one-dimensional Dirac equation with position dependent mass in the generalized asymmetric Woods-Saxon potential is solved in terms of the hypergeometric functions. The transmission and reflection coefficients are obtained by considering the one-dimensional electric current density for the Dirac particle and the equation describing the bound states is found by utilizing the continuity conditions of the obtained wave function. Also, by using the generalized asymmetric Woods-Saxon potential solutions, the scattering states are found out without making calculation for the Woods-Saxon, Hulthen, cusp potentials, and so forth, which are derived from the generalized asymmetric Woods-Saxon potential and the conditions describing transmission resonances and supercriticality are achieved. At the same time, the data obtained in this work are compared with the results achieved in earlier studies and are observed to be consistent.
Intense laser field effects on a Woods-Saxon potential quantum well
Restrepo, R. L.; Morales, A. L.; Akimov, V.; Tulupenko, V.; Kasapoglu, E.; Ungan, F.; Duque, C. A.
2015-11-01
This paper presents the results of the theoretical study of the effects of non-resonant intense laser field and electric and magnetic fields on the optical properties in an quantum well (QW) make with Woods-Saxon potential profile. The electric field and intense laser field are applied along the growth direction of the Woods-Saxon quantum well and the magnetic field is oriented perpendicularly. To calculate the energy and the wave functions of the electron in the Woods-Saxon quantum well, the effective mass approximation and the method of envelope wave function are used. The confinement in the Woods-Saxon quantum well is changed drastically by the application of intense laser field or either the effect of electric and magnetic fields. The optical properties are calculated using the compact density matrix.
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Feizi, H.; Rajabi, A.A.; Shojaei, M.R.
2011-01-01
In this work, the three dimensional Woods-Saxon potential is studied within the context of Supersymmetry Quantum Mechanics. We have applied the SUSY method by using the Pekeris approximation to the centrifugal potential l ≠ 0 states. By application of this method, it is possible to solve the Schroedinger equation for this potential. We obtain exactly bound state spectrum and wave function of Woods-Saxon potential for nonzero angular momentum. Hamiltonian hierarchy method and the shape invariance property are used in the calculations. (authors)
A semi-relativistic treatment of spinless particles subject to the nuclear Woods-Saxon potential
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Hamzavi, M.; Ikhdair, S.M.; Rajabi, A.A.
2013-01-01
By applying an appropriate Pekeris approximation to deal with the centrifugal term, we present an approximate systematic solution of the two-body spinless Salpeter (SS) equation with the Woods-Saxon interaction potential for an arbitrary l-state. The analytical semi-relativistic bound-state energy eigenvalues and the corresponding wave functions are calculated. Two special cases from our solution are studied: the approximated Schroedinger-Woods-Saxon problem for an arbitrary l-state and the exact s-wave (l=0). (authors)
OWL: A code for the two-center shell model with spherical Woods-Saxon potentials
Diaz-Torres, Alexis
2018-03-01
A Fortran-90 code for solving the two-center nuclear shell model problem is presented. The model is based on two spherical Woods-Saxon potentials and the potential separable expansion method. It describes the single-particle motion in low-energy nuclear collisions, and is useful for characterizing a broad range of phenomena from fusion to nuclear molecular structures.
Stochastic Resonance with a Joint Woods-Saxon and Gaussian Potential for Bearing Fault Diagnosis
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Haibin Zhang
2014-01-01
Full Text Available This work aims for a new stochastic resonance (SR model which performs well in bearing fault diagnosis. Different from the traditional bistable SR system, we realize the SR based on the joint of Woods-Saxon potential (WSP and Gaussian potential (GP instead of a reflection-symmetric quartic potential. With this potential model, all the parameters in the Woods-Saxon and Gaussian SR (WSGSR system are not coupled when compared to the traditional one, so the output signal-to-noise ratio (SNR can be optimized much more easily by tuning the system parameters. Besides, a smoother potential bottom and steeper potential wall lead to a stable particle motion within each potential well and avoid the unexpected noise. Different from the SR with only WSP which is a monostable system, we improve it into a bistable one as a general form offering a higher SNR and a wider bandwidth. Finally, the proposed model is verified to be outstanding in weak signal detection for bearing fault diagnosis and the strategy offers us a more effective and feasible diagnosis conclusion.
Woods-Saxon potential parametrization at large deformations for plutonium odd isotopes
International Nuclear Information System (INIS)
Garcia, F.; Garrote, E.; Yoneama, M.L.; Arruda-Neto, J.D.T.; Mesa, J.; Bringas, F.; Likhachev, V.P.; Rodriguez, O.; Guzman, F.
1999-01-01
The structure of single-particle levels in the second minima of 237,239,241 Pu was analyzed with the help of an axially-deformed Woods-Saxon potential. The nuclear shape was parametrized in terms of the cassinian ovaloids. A parametrization of the spin-orbit part of the potential was obtained in the region corresponding to large deformations (second minimum), depending only on the nuclear surface area. With this parametrization, we were able to reproduce successfully the spin, parity and energies of the rotational band built on the 8 μ s isomeric state in 239 Pu and, also, a spin assignment for both isomeric states in 237 Pu and 241 Pu was carried out. (orig.)
Woods-Saxon potential parametrization at large deformations for odd-plutonium nuclei
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Garcia, F.; Yoneama, M.L.; Arruda Neto, J.D.T.; Mesa, J.; Bringas, F.; Dias, J.F.; Likhachev, V.P.
1997-01-01
The structure of the the single-particle levels in the secondary minima of 237,239,241 Pu fissioning nuclei is analysed with the help of an axially-deformed Woods-Saxon potential. The nuclear shape was parametrized in terms of the Cassinian ovaloids. The parametrization of the spin-orbit part of the potential in the region corresponding to large deformations (second minimum), which depends only on the nuclear surface area, B s , was obtained. With this relation we were able to reproduce successfully the spin (parity) and the energies of the rotational band built on the 8μs isomeric rate in 239 Pu and also to make a spin assignment for both isomer states in 237 Pu and 241 Pu. (author)
Fusion dynamics of 2020Ne + 20882Pb reaction using static and energy dependent Woods-Saxon potential
International Nuclear Information System (INIS)
Gautam, Manjeet Singh; Kaur, Amandeep; Sharma, Manoj K.
2015-01-01
The present work compares the theoretical predictions based on static Woods-Saxon potential and the EDWSP model along with one dimensional Wong formula. For 20 20 Ne + 208 82 Pb reaction, the theoretical calculations obtained by using static Woods-Saxon potential are substantially smaller than that of experimental data at below barrier energies and explain the fusion data at above barrier energies only. On the other hand, the EDWSP model based calculations adequately describe the observed fusion enhancement of 20 20 Ne + 208 82 Pb reaction in whole range of energy spread across the Coulomb barrier. Furthermore, a wide range of the diffuseness parameter ranging from 0.96 fm to 0.85 fm is required to address the sub-barrier fusion data
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Ikhdair, S.M.; Sever, R.
2007-01-01
The exact solution of the one-dimensional Klein-Gordon equation of the PT-symmetric generalized Woods-Saxon potential is obtained. The exact energy eigenvalues and wavefunctions are derived analytically by using the Nikiforov and Uvarov method. In addition, the positive and negative exact bound states of the s-states are also investigated for different types of complex generalized Woods-Saxon potentials. (Abstract Copyright [2007], Wiley Periodicals, Inc.)
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Bekir Can LÜTFÜOĞLU
2017-04-01
Full Text Available The energy eigenvalues and the wave functions of an α particle in a Bohrium 270 nucleus have been calculated by solving Schrödinger equation for Generalized Symmetric Woods-Saxon potential. Using the energy spectrum by excluding and including the quasi-bound eigenvalues, entropy, internal energy, Helmholtz energy, and specific heat, as functions of reduced temperature have been calculated. Stability and emission characteristics have been interpreted in terms of the wave and thermodynamic functions. The kinetic energy of a decayed α particle was calculated using the quasi-bound states, which has been found close to the experimental value.
Bonding wood-saxon potential and the mechanism of resonance states in the ''1''2C+''1''2C system
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Kim, G.; Khaydarov, R.R.
2001-01-01
In present work the ''1''2C+''1''2C system are investigated in the realistic Woods--Saxon potential with Coulomb interaction. The comparison of the calculated states with the experimental data has shown, that the observed (identified) resonances may be explained by the single-channel description, i.e., as potential resonances. The quadrupole moments and transition probabilities for low-laying states have been calculated
Molecular versus squared Woods-Saxon α-nucleus potentials in the 27Al(α, t)28Si reaction
International Nuclear Information System (INIS)
Abdullah, M N A; Das, S K; Tariq, A S B; Mahbub, M S; Mondal, A S; Uddin, M A; Basak, A K; Gupta, H M Sen; Malik, F B
2003-01-01
The differential cross-section of the 27 Al(α, t) 28 Si reaction for 64.5 MeV incident energy has been reanalysed in DWBA with full finite range using a squared Woods-Saxon (Michel) α-nucleus potential with the modified value of the depth parameter α = 2.0 as reported in a comment article by Michel and Reidemeister. This new value produces significant improvement in fitting the data of the reaction with its overall performance, in some cases, close to that previously observed for the molecular potential. Although the non-monotonic shallow molecular potential with a soft repulsive core and the Michel potentials produce the same quality fits to the elastic scattering and non-elastic processes, they are not phase equivalent. The two types of potential produce altogether different cross-sections, particularly at large reaction angles. The importance of the experimental cross-sections at large angles for both elastic scattering and non-elastic processes is elucidated
Nuclear structure approach to the calculation of the imaginary alpha-nucleus optical potential
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Dermawan, H.; Osterfeld, F.; Madsen, V.A.
1981-01-01
A microscopic calculation of the second-order imaginary optical potential for 40 (Ca(α,α) is made for incident energies of 31 and 100 MeV using RPA transition densities for intermediate excited states. The projectile is treated as an elementary particle, and the alpha-nucleon interaction is normalized by fitting 3 - inelastic cross sections with a folded M3Y potential. The use of an optical Green's function for the intermediate propagator is found to be important. Equivalent local potentials are obtained and used to calculate elastic scattering cross sections. Agreement with low-angle experimental data is fair at 31 MeV, but at 100 MeV the calculated cross sections indicate much too little absorption. 9 figures, 1 table
Energy Technology Data Exchange (ETDEWEB)
Luk` yanov, V K; Permyakov, V P; Chubov, Yu V
1999-12-31
The eikonal phase is needed for the analytical calculations for the nuclear scattering in the high energy approximation (E>>U, kR>>1). In this paper we obtain its model expression for scattering on Woods-Saxon potential which with a good accuracy reproduces its behaviour in complex plane which is found numerically. In the case one evaluates explicitly the scattering amplitude using saddle-point method makes the physics more understandable. The numerical amplitudes and cross sections of nucleus-nucleus scattering are compared with exact calculations. (author) 9 refs., 7 figs. Submitted to Izvestiya Akademii Nauk. Rossijskaya Akademiya Nauk. Seriya Fizicheskaya
International Nuclear Information System (INIS)
Kumar, Rajiv; Goyal, Monika; Roshni; Singh, Pradeep; Kharab, Rajesh
2017-01-01
In present work, the S-matrix has been evaluated by using simple Woods-Saxon formula as well as the realistic expression for a number of projectiles varying from 26N e to 76 Ge at intermediate incident beam energies ranging from 30 MeV/A to 300 MeV/A. The target is 197 Au in each and every case. The realistic S-matrix is compared with that of obtained by using the simple Woods-Saxon formula. The motive of this comparison is to fix the value of otherwise free Δ so that the much involved evaluation of realistic S-matrix can be replaced by the simple Woods-Saxon formula
International Nuclear Information System (INIS)
Molique, H.; Dudek, J.
1997-01-01
A particle-number conserving approach is presented to solve the nuclear mean-field plus pairing Hamiltonian problem with a realistic deformed Woods-Saxon single-particle potential. The method is designed for the state-dependent monopole pairing Hamiltonian H pair =summation αβ G αβ c α † c bar α † c bar β c β with an arbitrary set of matrix elements G αβ . Symmetries of the Hamiltonians on the many-body level are discussed using the language of P symmetry introduced earlier in the literature and are employed to diagonalize the problem; the only essential approximation used is a many-body (Fock-space) basis cutoff. An optimal basis construction is discussed and the stability of the final result with respect to the basis cutoff is illustrated in details. Extensions of the concept of P symmetry are introduced and their consequences for an optimal many-body basis cutoff construction are exploited. An algorithm is constructed allowing to solve the pairing problems in the many-body spaces corresponding to p∼40 particles on n∼80 levels and for several dozens of lowest lying states with precision ∼(1 endash 2) % within seconds of the CPU time on a CRAY computer. Among applications, the presence of the low-lying seniority s=0 solutions, that are usually poorly described in terms of the standard approximations (BCS, HFB), is discussed and demonstrated to play a role in the interpretation of the spectra of rotating nuclei. copyright 1997 The American Physical Society
Symmmetric double-well potential with Saxon-Woods tail and Pade approximations
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Niculescu, V.I.R.; Catana, D.
1995-01-01
In the present work we introduce a symmetric double-well potential with Woods-Saxon tail. The Woods-Saxon parts are replaced by Pade approximation.In this way the matrix elements of this potential form can be evaluated by the theory of complex functions. This results in a shorter computational time. (author). 1 fig., 1 tab., 7 refs
On the rational approximation of the bidimensional potentials
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Niculescu, V.I.R; Catana, D.
1997-01-01
In the present letter we introduced a symmetrical bidimensional potential with Woods-Saxon tail. The potential approximation has permitted to replace in the matrix the evaluation of double integration by a product of two integrals. That implied a complexity reduction in the Hamiltonian eigenvalue and eigenvector evaluation. Also, the harmonic bidimensional basis simplifies significantly the evaluation of electric multipole operators. (authors)
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Bang, J.M.; Gareev, F.A.
1977-01-01
Different convergence properties of the Sturm-Liouville expansion are investigated with particular attention to the case of states which satisfy Schroedinger-like equations with a fixed energy and different depths of a potential, particulary of the Woods-Saxon used in nuclear physics
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Ermer, M.; Clement, H.; Frank, G.; Grabmayr, P.; Heberle, N.; Wagner, G.J.
1989-01-01
High-quality data for elastic proton, deuteron and α-particle scattering on 40 Ca and 208 Pb at 26-30 MeV/N have been analyzed in terms of the model-unrestricted Fourier-Bessel concept. While extracted scattering potentials show substantial deviations from Woods-Saxon shapes, their real central parts are well described by folding calculations using a common effective nucleon-nucleon interaction with a weak density dependence. (orig.)
The cranking moment of inertia in a static potential
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Bengtsson, R.; Hamamoto, I.; Ibarra, R.H.
1978-01-01
Taking into account the self-consistency condition for the deformation, the authors estimate the cranking moment of inertia in the absence of pair-correlations for the Woods-Saxon potential and various versions of the modified oscillator potential. The authors investigate the expectation that in a static potential the moment of inertia is almost equal to the rigid-body moment of inertia at the self-consistent deformation. They examine especially the consequence of the presence of the l 2 term in the conventional modified oscillator potential. (Auth.)
A new method for solving the two-center problem with relativistic potentials
International Nuclear Information System (INIS)
Gareev, F.A.; Gizzatkulov, M.Ch.
1977-01-01
A method has been proposed for the solution of the two-center problem with realistic potentials. It consists of two steps: first, a separable approximation to the single particle potentials is made and then the two-center problem with these separable potentials is solved exactly. The only approximations are introduced at the first stage in a well controllable way. As an example, we have calculated the single-particle energies and wave functions in the field of two 16 O like the Woods-Saxon potentials as functions of their distance R
Global dependence of optical potential parameters for alpha particles with energies up to 80 MeV
International Nuclear Information System (INIS)
Kuterbekov, K.A.; Zholdybaev, T.K.; Sadykov, B.M.; Mukhambetzhan, A.; Kukhtina, I.N.; Penionzhkevich, Yu.Eh.
2002-01-01
Global (energy and mass) dependences of optical potential for α-particles with energies up to 80 MeV have been received. A Woods-Saxon form factor for macroscopic potential has been used. Energy and mass dependences of the semi-microscopic α-particle potential parameters have been investigated for the first time. In general, a good description of elastic and inelastic differential and total reactions cross sections for different nuclei using the revealed global parameters has been received within the framework of macroscopic and semi-microscopic approaches
Dirac-global fits to calcium elastic scattering data in the range 21-200 MeV
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Cooper, E.D.
1988-01-01
We present a global relativistic optical model for p+ 40 Ca consisting of Lorentz scalar and vector potentials parametrized as a function of energy. The shapes chosen are Woods-Saxons for the real potentials, and a linear combination of Woods-Saxons and derivative Woods-Saxons for the imaginary potentials. (orig.)
The use of Ixaru's method in locating the poles of the S-matrix in strictly finite-range potentials
Energy Technology Data Exchange (ETDEWEB)
Vertse, Tamas; Lovas, R. G.; Racz, A.; Salamon, P. [University of Debrecen, Faculty of Informatics, Chair of Applied Mathematics and Probability, Debrecen, Hungary and Institute of Nuclear Research of the Hungarian Academy of Sciences, Debrecen (Hungary); Institute of Nuclear Research of the Hungarian Academy of Sciences, Debrecen (Hungary); University of Debrecen, Faculty of Informatics, Chair of Applied Mathematics and Probability, Debrecen (Hungary); Institute of Nuclear Research of the Hungarian Academy of Sciences, Debrecen (Hungary)
2012-09-26
Energies of the S-matrix poles are calculated by solving the radial Schroedinger equation numerically by using Ixaru's CPM(2) method. The trajectories of the poles in the complex wave number plane are determined for two nuclear potentials that are zero beyond finite distances. These are the Woods-Saxon form with cutoff and the Salamon-Vertse potential, which goes to zero smoothly at a finite distance. Properties of the trajectories are analyzed for real and complex values of the depths of the corresponding potentials.
Resolution of potential ambiguities through farside angular structure: Semiclassical analysis
International Nuclear Information System (INIS)
Fricke, S.H.; Brandan, M.E.; McVoy, K.W.
1988-01-01
The optical potential fits summarized in the preceding paper are subjected to a semiclassical analysis of the Ford-Wheeler--Knoll-Schaeffer type. The important broad dips in their farside cross sections, which are essential in greatly reducing potential ambiguities, are found (in partial agreement with a suggestion of Goldberg's) to be mainly weak ''Airy'' or rainbow minima, that serve to identify deeply penetrating trajectories. The semiclassical analysis also permits the identification and understanding of a new category of discrete and continuous potential ambiguities, and suggests the manner in which specific features of the angular distributions (such as spacings and depths of various angular minima) determine the Woods-Saxon parameters found by a chi-squared search
Calculation of real optical model potential for heavy ions in the framework of the folding model
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Goncharov, S.A.; Timofeyuk, N.K.; Kazacha, G.S.
1987-01-01
The code for calculation of a real optical model potential in the framework of the folding model is realized. The program of numerical Fourier-Bessel transformation based on Filon's integration rule is used. The accuracy of numerical calculations is ∼ 10 -4 for a distance interval up to a bout (2.5-3) times the size of nuclei. The potentials are calculated for interactions of 3,4 He with nuclei from 9 Be to 27 Al with different effective NN-interactions and densities obtained from electron scattering data. Calculated potentials are similar to phenomenological potentials in Woods-Saxon form. With calculated potentials the available elastic scattering data for the considered nuclei in the energy interval 18-56 MeV are analysed. The needed renormalizations for folding potentials are < or approx. 20%
Classical properties and semiclassical quantization of a spherical nuclear potential
International Nuclear Information System (INIS)
Carbonell, J.; Brut, F.; Arvieu, R.; Touchard, J.
1984-03-01
The geometrical properties of the classical energy-action surface are studied for a nuclear Woods-Saxon-like spherical potential, in connection with the E.B.K. semiclassical method of quantization. Comparisons are made with other well known cases: the spherical harmonic oscillator and the spherical billiard. The shift of single particle energies from A = 208 to A = 16 is calculated by a simple method inspired by the Erhenfest adiabatic invariants. Semiclassical results are then compared with exact Schroedinger energies. It is seen that the most significant features of the single particle spectrum are explained by local properties of the energy action surface (curvature, slope) and by their evolution with the particle number
Bonitati, Joey; Slimmer, Ben; Li, Weichuan; Potel, Gregory; Nunes, Filomena
2017-09-01
The calculable form of the R-matrix method has been previously shown to be a useful tool in approximately solving the Schrodinger equation in nuclear scattering problems. We use this technique combined with the Gauss quadrature for the Lagrange-mesh method to efficiently solve for the wave functions of projectile nuclei in low energy collisions (1-100 MeV) involving an arbitrary number of channels. We include the local Woods-Saxon potential, the non-local potential of Perey and Buck, a Coulomb potential, and a coupling potential to computationally solve for the wave function of two nuclei at short distances. Object oriented programming is used to increase modularity, and parallel programming techniques are introduced to reduce computation time. We conclude that the R-matrix method is an effective method to predict the wave functions of nuclei in scattering problems involving both multiple channels and non-local potentials. Michigan State University iCER ACRES REU.
Dependence of isobar-analog state properties on variable part of Coulomb potential
International Nuclear Information System (INIS)
Dzhafarov, I.G.; Kuliev, A.A.; Salamov, D.I.
1986-01-01
Within the framework of the self-consistent approach and with the method of strength functions the fragmentation of isobar-analog state (IAS) properties for all isobarie 0 + -states is investigated. Microscopic values of IAS energy, matrix elements of allowed and forbidden Fermi transitions as well as isospin impurity values in ground states of parent nuclei are obtained. Numerical calculations carried out for 42 Ca 42 Sc, 48 Ca 48 Sc, 64 Zn 64 Ga, 66 Zn 66 Ga, 90 Zr 90 Nb, 208 Pb 208 Bi isobaric nuclei with Woods-Saxon potential, are compared with predictions of different approches and experiment. The developed model by the authors permits to describe sufficiently well the experimental data
On using of R-matrix approach for description of nucleon scattering by potential with diffuse edge
International Nuclear Information System (INIS)
Tertychnyj, G.Ya.; Yadrovskij, E.L.
1982-01-01
Problems of convergence of R-matrix method for calculation of scattering phases and bound states of neutrons in the Woods-Saxon potential are investigated. It is revealed that this convergence in respect to the number of R-matrix poles turns to be faster if the value of the parameter of boundary conditions bsub(ej)sup(0) is close to the value of logarithmic derivative of the function of continuous spectrum at given energy E and radius of joining a. Bound states are satisfactorily described in unipolar approximation in a wide range of energy and bsub(ej)sup(0) parameter variations. The conducted comparison of the R-matrix method with the method of numerical integration testifies to their equivalence irrespective of the choice of a and bsub(ej)sup(0) parameters, but under the condition that the R-matrix series comprises a large number of members
Chai, Qing-Zhen; Zhao, Wei-Juan; Liu, Min-Liang; Wang, Hua-Lei
2018-05-01
Static fission barriers for 95 even-even transuranium nuclei with charge number Z = 94–118 have been systematically investigated by means of pairing self-consistent Woods-Saxon-Strutinsky calculations using the potential energy surface approach in multidimensional (β 2, γ, β 4) deformation space. Taking the heavier 252Cf nucleus (with the available fission barrier from experiment) as an example, the formation of the fission barrier and the influence of macroscopic, shell and pairing correction energies on it are analyzed. The results of the present calculated β 2 values and barrier heights are compared with previous calculations and available experiments. The role of triaxiality in the region of the first saddle is discussed. It is found that the second fission barrier is also considerably affected by the triaxial deformation degree of freedom in some nuclei (e.g., the Z=112–118 isotopes). Based on the potential energy curves, general trends of the evolution of the fission barrier heights and widths as a function of the nucleon numbers are investigated. In addition, the effects of Woods-Saxon potential parameter modifications (e.g., the strength of the spin-orbit coupling and the nuclear surface diffuseness) on the fission barrier are briefly discussed. Supported by National Natural Science Foundation of China (11675148, 11505157), the Project of Youth Backbone Teachers of Colleges and Universities of Henan Province (2017GGJS008), the Foundation and Advanced Technology Research Program of Henan Province (162300410222), the Outstanding Young Talent Research Fund of Zhengzhou University (1521317002) and the Physics Research and Development Program of Zhengzhou University (32410017)
Diffuse versus square-well confining potentials in modelling A-C60 atoms
International Nuclear Information System (INIS)
Dolmatov, V K; King, J L; Oglesby, J C
2012-01-01
A perceived advantage for the replacement of a discontinuous square-well pseudo-potential, which is often used by various researchers as an approximation to the actual C 60 cage potential in calculations of endohedral atoms A-C 60 , by a more realistic diffuse potential is explored. The photoionization of endohedral H-C 60 and Xe-C 60 is chosen as the case study. The diffuse potential is modelled by a combination of two Woods-Saxon potentials. It is demonstrated that photoionization spectra of A-C 60 atoms are largely insensitive to the degree η of diffuseness of the potential borders, in a reasonably broad range of ηs. These spectra are found to be insensitive to discontinuity of the square-well potential as well. Both potentials result in practically identical calculated spectra. New numerical values for the set of square-well parameters, which lead to a better agreement between experimental and theoretical data for A-C 60 spectra, are recommended for future studies. (paper)
Phenomenological optical potentials and optical model computer codes
International Nuclear Information System (INIS)
Prince, A.
1980-01-01
An introduction to the Optical Model is presented. Starting with the purpose and nature of the physical problems to be analyzed, a general formulation and the various phenomenological methods of solution are discussed. This includes the calculation of observables based on assumed potentials such as local and non-local and their forms, e.g. Woods-Saxon, folded model etc. Also discussed are the various calculational methods and model codes employed to describe nuclear reactions in the spherical and deformed regions (e.g. coupled-channel analysis). An examination of the numerical solutions and minimization techniques associated with the various codes, is briefly touched upon. Several computer programs are described for carrying out the calculations. The preparation of input, (formats and options), determination of model parameters and analysis of output are described. The class is given a series of problems to carry out using the available computer. Interpretation and evaluation of the samples includes the effect of varying parameters, and comparison of calculations with the experimental data. Also included is an intercomparison of the results from the various model codes, along with their advantages and limitations. (author)
Deformed potential energy of $^{263}Db$ in a generalized liquid drop model
Chen Bao Qiu; Zhao Yao Lin; 10.1088/0256-307X/20/11/009
2003-01-01
The macroscopic deformed potential energy for super-heavy nuclei /sup 263/Db, which governs the entrance and alpha decay channels, is determined within a generalized liquid drop model (GLDM). A quasi- molecular shape is assumed in the GLDM, which includes volume-, surface-, and Coulomb-energies, proximity effects, mass asymmetry, and an accurate nuclear radius. The microscopic single particle energies derived from a shell model in an axially deformed Woods- Saxon potential with a quasi-molecular shape. The shell correction is calculated by the Strutinsky method. The total deformed potential energy of a nucleus can be calculated by the macro-microscopic method as the summation of the liquid-drop energy and the Strutinsky shell correction. The theory is applied to predict the deformed potential energy of the experiment /sup 22/Ne+/sup 241/Am to /sup 263/Db* to /sup 259/Db+4 n, which was performed on the Heavy Ion Accelerator in Lanzhou. It is found that the neck in the quasi-molecular shape is responsible for t...
The role of spin-orbit potential in nuclear prolate-shape dominance
Energy Technology Data Exchange (ETDEWEB)
Takahara, Satoshi, E-mail: staka@ks.kyorin-u.ac.jp [Kyorin University, School of Medicine, Mitaka, Tokyo 181-8611 (Japan); Onishi, Naoki [University of Tokyo (Japan); University of Yamanashi (Japan); Shimizu, Yoshifumi R. [Department of Physics, Graduate School of Science, Kyushu University, Fukuoka 812-8581 (Japan); Tajima, Naoki [Department of Applied Physics, University of Fukui, 3-9-1 Bunkyo, Fukui 910-8507 (Japan)
2011-08-26
It is confirmed, in terms of the Woods-Saxon-Strutinsky method, that the spin-orbit potential plays a decisive role in the predominance of prolate deformation, which has been a long standing problem in nuclear physics. It is originated from the combined effects of the spin-orbit coupling and the diffused surface of the potential, in agreement with the previous work based on a more schematic Nilsson-Strutinsky method. The degree of prolate-shape dominance exhibits an oscillatory behavior with respect to the strength of spin-orbit potential and, the prolate-shape dominance is realized at the proper strength of the spin-orbit potential together with the standard surface diffuseness; this oscillatory behavior disappears in case of small diffuseness corresponding to ellipsoidal cavity. The calculated energy differences between oblate and prolate minima in this Letter are consistent with those of our extensive self-consistent calculations of the Hartree-Fock + BCS method with the Skyrme interaction.
The role of spin-orbit potential in nuclear prolate-shape dominance
International Nuclear Information System (INIS)
Takahara, Satoshi; Onishi, Naoki; Shimizu, Yoshifumi R.; Tajima, Naoki
2011-01-01
It is confirmed, in terms of the Woods-Saxon-Strutinsky method, that the spin-orbit potential plays a decisive role in the predominance of prolate deformation, which has been a long standing problem in nuclear physics. It is originated from the combined effects of the spin-orbit coupling and the diffused surface of the potential, in agreement with the previous work based on a more schematic Nilsson-Strutinsky method. The degree of prolate-shape dominance exhibits an oscillatory behavior with respect to the strength of spin-orbit potential and, the prolate-shape dominance is realized at the proper strength of the spin-orbit potential together with the standard surface diffuseness; this oscillatory behavior disappears in case of small diffuseness corresponding to ellipsoidal cavity. The calculated energy differences between oblate and prolate minima in this Letter are consistent with those of our extensive self-consistent calculations of the Hartree-Fock + BCS method with the Skyrme interaction.
Microscopic theory for nucleon-nucleus optical potential in intermediate energies
International Nuclear Information System (INIS)
He Guozhu; Cai Chonghai
1984-01-01
Based on the scattering theory of KMT and FGH we calculate the nucleon-nucleus optical potentials of 4 He, 16 O and 40 Ca from the Paris N-N potential given by M. Lacombe et al. The real part Vsub(R)(r) of our optential has the form of Woods-Saxon when the kinetic energy E of the incident nucleon is low. The depth of Vsub(R)(r) will decrease as E increases, and it turns into positive in the interior of nucleus when E approx.= 300 MeV. The repulsive effect in the interior of nucleus increases rapidly as E increases even more, butthere always exists some attractive effect at the surface of nucleus. Therefore, Vsub(R)(r) has generally the wine-bottle bottom shape. We also calculate the quatity Jv/N = (4π/N)∫sub(0)sub(infinity)Vsub(R)(r)r 2 dr. Our results are basically in acordance with those of M.Jaminon et al's relativistic Hatree calculation as well as the experimental results. In this work we also calculate the imaginary part of optical potential and its variation with the kinetic energy of the incident nucleon
Microscopic and semi-classical treatments of octupole deformation in the light actinides
International Nuclear Information System (INIS)
Chasman, R.R.
1984-01-01
Microscopic and semi-classical descriptions of octupole deformation are compared. New semi-classical results, obtained with the use of a Woods-Saxon potential are presented. Comparisons with experiment are made. 21 references
Fan, T. S.; Wang, Z. M.; Zhu, X.; Zhu, W. J.; Zhong, C. L.
2017-09-01
In this work, the nuclear potential-energy of the deformed nuclei as a function of shape coordinates is calculated in a five-dimensional (5D) parameter space of the axially symmetric generalized Lawrence shapes, on the basis of the macroscopic-microscopic method. The liquid-drop part of the nuclear energy is calculated according to the Myers-Swiatecki model and the Lublin-Strasbourg-drop (LSD) formula. The Woods-Saxon and the folded-Yukawa potentials for deformed nuclei are used for the shell and pairing corrections of the Strutinsky-type. The pairing corrections are calculated at zero temperature, T, related to the excitation energy. The eigenvalues of Hamiltonians for protons and neutrons are found by expanding the eigen-functions in terms of harmonic-oscillator wave functions of a spheroid. Then the BCS pair is applied on the smeared-out single-particle spectrum. By comparing the results obtained by different models, the most favorable combination of the macroscopic-microscopic model is known as the LSD formula with the folded-Yukawa potential. Potential-energy landscapes for actinide isotopes are investigated based on a grid of more than 4,000,000 deformation points and the heights of static fission barriers are obtained in terms of a double-humped structure on the full 5D parameter space. In order to locate the ground state shapes, saddle points, scission points and optimal fission path on the calculated 5D potential-energy surface, the falling rain algorithm and immersion method are designed and implemented. The comparison of our results with available experimental data and others' theoretical results confirms the reliability of our calculations.
International Nuclear Information System (INIS)
Sanetullaev, A.; Igamov, S.B.; Yarmukhamedov, R.
2004-01-01
Full text: Obtaining the extremely low energy cross sections for the reaction 7 Be(p,γ ) 8 B is of great interest for a reliable estimation of the rate of this reaction, which is crucial for an accurate determination of the solar neutrino flux. At present, in current literature, there is a rather wide spread in estimation of this rate (see, for instance, Ref. [1] and references therein). In this work, the modified two-body potential approach for analysis of the astrophysical S- factor S(E) for the peripheral direct radiative capture 7 Be(p,γ ) 8 B reaction of astrophysical interest is applied, in which the additional conditions of verification of the peripheral character of the reaction under consideration are formulated. The method involves the information on the asymptotic normalization coefficient (ANC) for the virtual decay 8 B → 7 Be+p and allows one to exclude the model dependence of the calculated direct astrophysical S-factor S(E) on the geometric parameters (radius r 0 and diffuseness a) of the adopted Woods-Saxon potential, which is usually used for calculations both for the two-body ( 7 Be+p)-bound state and for the 7 Be p -scattering state. The rather precise experimental astrophysical S-factor, S exp (E), in the energy range 100 7 Be(p,γ ) 8 B reaction, measured recently by the authors of Ref. [1] is used for the analysis. It is demonstrated that at extremely low energies this reaction is strongly peripheral and the measured S exp (E) can be used as an independent source of getting the information about the ANC. The new information about values of the ANC is obtained with an estimation of the weighted mean errors for them, which involves both the experimental errors of the S exp (E), and uncertainty of the method not exceeding 4%. The extracted value of the ANC is equal to C 2 =C 2 1/2 +C 2 3/2 =5.68± 0.15 fm -1 , where the indices show the value total angular momentum of the proton in the (p+ 7 Be)-bound state of 8 B. It was also demonstrated
Optical model representation of coupled channel effects
International Nuclear Information System (INIS)
Wall, N.S.; Cowley, A.A.; Johnson, R.C.; Kobas, A.M.
1977-01-01
A modification to the usual 6-parameter Woods-Saxon parameterization of the optical model for the scattering of composite particles is proposed. This additional real term reflects the effect of coupling other channels to the elastic scattering. The analyses favor a repulsive interaction for this term, especially for alpha particles. It is found that the repulsive term when combined with a Woods-Saxon term yields potentials with central values and volume integrals similar to those found by uncoupled elastic scattering calculations. These values are V(r = 0) approximately equal to 125 MeV and J/4A approximately equal to 300 MeV-fm 3
Extraction of Spin-Orbit Interactions from Phase Shifts via Inversion
International Nuclear Information System (INIS)
Lun, D.R.; Buckman, S.J.
1997-01-01
An exact inversion procedure for obtaining the central and spin-orbit potential from phase shifts at fixed energy is described. The method, based on Sabatier interpolation formulas, reduces the nonlinear problem to linear-algebraic equations. We have tested the method with a Woods-Saxon potential with a strong spin-orbit component. copyright 1997 The American Physical Society
International Nuclear Information System (INIS)
Zuber, K.; Balouka, D.; Beck, F.A.; Byrski, T.; Curien, D.; France, G. de; Duchene, G.; Gehringer, C.; Haas, B.; Merdinger, J.C.; Romain, P.; Santos, D.; Styczen, J.; Vivien, J.P.; Dudek, J.; Szymanski, Z.; Werner, T.R.
1991-01-01
Two discrete superdeformed (SD) bands have been identified in the nucleus 147 Gd and the twin-band mechanism studied by comparison with SD results for 146,148 Gd. Theoretical interprettion in terms of nucleonic orbitals with the Woods-Saxon potential is consistent with the pseudo-spin symmetry picture and the octupole susceptibility mechanism predicted by theory. (orig.)
Energy Technology Data Exchange (ETDEWEB)
Zuber, K.; Balouka, D.; Beck, F.A.; Byrski, T.; Curien, D.; France, G. de; Duchene, G.; Gehringer, C.; Haas, B.; Merdinger, J.C.; Romain, P.; Santos, D.; Styczen, J.; Vivien, J.P.; Dudek, J.; Szymanski, Z.; Werner, T.R. (Strasbourg-1 Univ., 67 (France). Centre de Recherches Nucleaires)
1991-01-24
Two discrete superdeformed (SD) bands have been identified in the nucleus {sup 147}Gd and the twin-band mechanism studied by comparison with SD results for {sup 146,148}Gd. Theoretical interprettion in terms of nucleonic orbitals with the Woods-Saxon potential is consistent with the pseudo-spin symmetry picture and the octupole susceptibility mechanism predicted by theory. (orig.).
Discrete expansions of continuum wave functions
International Nuclear Information System (INIS)
Bang, J.; Ershov, S.N.; Gareev, F.A.; Kazacha, G.S.
1980-01-01
Different methods of expanding continuum wave functions in terms of discrete basis sets are discussed. The convergence properties of these expansions are investigated, both from a mathematical and a numerical point of view, for the case of potentials of Woods-Saxon and square well type. (orig.)
Spatial dependence of pair correlations (nuclear scissors)
International Nuclear Information System (INIS)
Bal'butsev, E.B.; Malov, L.A.
2009-01-01
The solution of time-dependent Hartree-Fock-Bogolyubov equations by the Wigner function moments method leads to the appearance of low-lying modes whose description requires accurate knowledge of the anomalous density matrix. It is shown that calculations with the Woods-Saxon potential satisfy this requirement
Integrals involving functions of the type (WS)sup(q)
International Nuclear Information System (INIS)
Srivastava, D.K.
1981-10-01
Analytical expressions for integrals involving functions of the Woods-Saxon type raised to the power of q are given. These are expected to be of immediate application in optical model studies and for obtaining various moments of the potential having such shapes. (author)
International Nuclear Information System (INIS)
Kharab, Rajesh; Chahal, Rajiv; Kumar, Rajiv
2017-01-01
In the present work we have analyzed the fusion excitation function for CF process using the simple Wong’s formula in conjunction with the energy dependent Woods-Saxon potential (EDWSP) in near barrier energy region for 7 Li+ 152 Sm, 197 Au and 209 Bi reactions
Gross theory of nuclear β-decay with shell effects
International Nuclear Information System (INIS)
Pabst, M.
1979-01-01
The present work tries to introduce shell effects selection rules into the gross theory systematically. Instead of an unbunched or bunched Fermigas spectrum a single-particle spectrum in the shell model with a Woods-Saxon potential is used. The knowledge of spin and parity of the levels allows us to introduce selection rules in an approximative way. (orig.)
Appropriate bare potentials for studying fusion induced by 6He
International Nuclear Information System (INIS)
Crema, E; Chamon, L.C; Gomes, P.R.S.
2007-01-01
Although there are some recent studies questioning the use of the same optical potential to explain simultaneously fusion and quasi-elastic experimental data [1] or even to explain deep sub-barrier- and above-barrier fusion [2], during the last decades, the bare nuclear interaction between the nuclei at near barrier energies has been widely represented by a frozen potential with a Woods-Saxon shape. Another well established fact is the strong dependence of nuclear reaction calculations on the choice of the primary interaction. Of course, comparison between data and theoretical calculations are strongly potential-dependent. So, the choice of an appropriate nuclear bare interaction between two colliding nuclei, although it is a difficult task, is a crucial step in the data interpretation. As one has not direct access to the true bare potential, some procedures have been developed in order to constrain the choice of the bare potential to be used. The first procedure is the analysis of the elastic scattering data within the context of an optical potential, where an imaginary potential is added to the real potential, in order to take into account the flux deviated from the elastic channel. The optical potential that gives the best fit to the elastic scattering data is then used to describe other reaction channels, even in coupled channel calculations including inelastic and transfer reactions in the coupling matrix. However, this kind of calculation suffers from several inconsistencies. Another procedure that has been widely used to obtain the bare potential is the fit of the high-energy fusion data by a single barrier penetration model (BPM). However this method also has its uncertainties, since there might be channels that hinder the fusion cross section at energies near and above the Coulomb barrier. Hence, the bare potential extracted through this method can be contaminated by different processes. The derivation of experimental barrier distributions probably is the
Modified two-body potential model to the 3He(α,γ)8B reaction at extremely low energies
International Nuclear Information System (INIS)
Igamov, S.B.; Santullaev, A.; Yarmukhamedov, R.
2005-01-01
Full text: A reliable estimation of rates of different nuclear astrophysical reactions A(α,γ)B responsible for light elements abundance is one of the most actual problem of the modern nuclear astrophysics. Solution of this problem is impossible without obtaining of rather low energy cross sections (or equivalently its astrophysical S-factor (AS) S Aa (E)) for such reactions as 3 He(α,γ) 8 B, 7 Be(p,γ) 8 B, etc. In the present work modified two-body potential approach allowing to determine both the asymptotic normalization constant (ANC) of the overlap integral for the bound wave function f the nucleus B in the (A+α)-channel C Aα;1.j (or respective nuclear vertex constant for the virtual decay B→A+α, where 1(j) is orbital (total) angular momentum of a particle α in the nucleus B=(A+α), and the AS S Aα (E) at the stellar energies (E≤25 keV) from an analysis of the analysis of the S exp (E) for the peripheral direct capture reaction A(α,γ)B is developed. The method involves two additional conditions that verify the peripheral character of the reaction under consideration and on it S(E) is expressed i the terms of ANC C Aα;1.j as Z Aα;1.j =C Aα;1.j 2 /b l +j 2 , where b lj is the single-particle ANC for the wave function of the bound B=(A+α) state calculated within the shell model using the phenomenological Woods-Saxon potential with the geometric parameters (a radius r 0 and a diffuseness a). The value of b lj strongly changes as a function (r 0 ,a)-pair is determined by variation of values of the parameters r 0 , and a in a wide physical acceptable range. The present method allows one to remove the model dependence of the calculated direct on S(E) on the geometric parameters r 0 , and a both for the two-body bound (A+α) state and the Aα-scattering state in minimum. The developed method has been applied to the analysis of the experimental S exp (E) of the direct capture 3 He(α,γ) 7 Be and 7 Be(p,γ) 8 B reactions at extremely low energies. By
Breakup threshold anomaly in the elastic scattering of 6Li on 27Al
International Nuclear Information System (INIS)
Figueira, J. M.; Niello, J. O. Fernandez; Abriola, D.; Arazi, A.; Capurro, O. A.; Barbara, E. de; Marti, G. V.; Heimann, D. Martinez; Negri, A. E.; Pacheco, A. J.; Padron, I.; Gomes, P. R. S.; Lubian, J.; Correa, T.; Paes, B.
2007-01-01
Elastic scattering of the weakly bound 6 Li on 27 Al was measured at near-barrier energies. The data analysis was performed using a Woods-Saxon shape optical potential and also using the double-folding Sao Paulo potential. The results show the presence of the breakup threshold anomaly (BTA), an anomalous behavior when compared with the scattering of tightly bound nuclei. This behavior is attributed to a repulsive polarization potential produced by the coupling to the continuum breakup states
Optical model studies of 6Li elastic scattering at 156 MeV
International Nuclear Information System (INIS)
Cook, J.; Gils, H.J.; Rebel, H.; Klewe-Nebenius, H.
1981-11-01
Differential cross sections for 6 Li elastic scattering at 156 MeV from 12 C, 40 Ca 90 Zr and 208 Pb are presented. The sensitivity to various potential forms is established by using Saxon Woods, Saxon-Woods-squred, density independent and density dependent folded potentials. The extent to which the experimental data determine the potentials and related quantities is discussed. (orig.) [de
Scattering of 130 MeV helions on 58Ni
International Nuclear Information System (INIS)
Djaloeis, A.; Alderliesten, C.; Bojowald, J.; Oelert, W.; Turek, P.
1982-01-01
Angular distributions for the tau + 58 Ni scattering to the (g.s., 0 + ) (1.45 MeV, 2 + ) and giant resonance (Esub(x) approximately 63Asup(-1/3) MeV) states in 58 Ni have been measured at Esub(tau) = 130 MeV in an angular range thetasub(c.m.) = 6 0 -83 0 . Optical model and DWBA analyses have been performed. The use of helion optical potentials with either a volume (Woods-Saxon) or a surface (Woods-Saxon derivative) absorption results in good fits to the g.s. and 1.45 MeV data. However, the volume absorption gives consistently a better fit quality. The discrete ambiguity of the helion optical potential has been resolved in favour of the shallow potential family. The giant resonance is found to have a dominant quadrupole (L=2) character with about 6% (EWSR) L=4 admixture. (Auth.)
Elastic and inelastic scattering of alpha particles from sup 46 Ti at E sub. alpha. = 35 MeV
Energy Technology Data Exchange (ETDEWEB)
Raghunatha Rao, V.; Sudarshan, M.; Sarma, A.; Singh, R. (North-Eastern Hill Univ., Shillong (India). Dept. of Physics); Banerjee, S.R.; Chintalapudi, S.N. (Bhabha Atomic Research Centre, Bombay (India). Variable Energy Cyclotron Project)
1991-12-01
Differential cross sections for elastic and inelastic scattering of 35 MeV alpha particles have been measured from {theta}{sub lab} =10{sup o} to 100{sup o} in 1{sup o}-2{sup o} steps. An optical model analysis of the elastic scattering data has been carried out using Woods-Saxon and Woods-Saxon squared radial dependences for real as well as imaginary parts of the potential. The most sensitive region of the potential in predicting the elastic scattering cross sections has been determined using a notch perturbation test. The problem of discrete family ambiguity in the optical model analysis of elastic data has also been investigated. The inelastic scattering data have been analysed in terms of the collective model using the distorted-wave Born approximation (DWBA), where the distorted waves are generated by the optical potential obtained from the elastic scattering data. (author).
Nuclear sizes and the Coulomb Displacement Energy
International Nuclear Information System (INIS)
Van der Werf, S.Y.
1997-01-01
Data on Coulomb Displacement Energies in the mass range A = 40 - 240 are analyzed in the deformed Liquid Drop model and in the independent particle model. Reduced half-widths of Woods-Saxon mean-field potential of the resulting neutron-excess distributions are deduced. It is argued that the Nolen-Schiffer anomaly may be lifted by allowing for a slight binding-energy dependence of the mean-field potential geometry. (author)
Temperature effects on nuclear pseudospin symmetry in the Dirac-Hartree-Bogoliubov formalism
Lisboa, R.; Alberto, P.; Carlson, B. V.; Malheiro, M.
2017-01-01
We present finite temperature Dirac-Hartree-Bogoliubov (FTDHB) calculations for the tin isotope chain to study the dependence of pseudospin on the nuclear temperature. In the FTDHB calculation, the density dependence of the self-consistent relativistic mean fields, the pairing, and the vapor phase that takes into account the unbound nucleon states are considered self-consistently. The mean field potentials obtained in the FTDHB calculations are fit by Woods-Saxon (WS) potentials to examine ho...
Simultaneous measurement of angular distribution of elastic scattering for 6Li, 7Be, and 8B in 58Ni
International Nuclear Information System (INIS)
Ruiz S, A.; Martinez Q, E.; Aguilera R, E.F.; Murillo O, G.; Lizcano C, D.; Gomez C, A.
2007-01-01
The experimental angular distributions of elastic scattering for the projectiles 6 Li, 7 Be, 8 B in 58 Ni were obtained. Using the Optical model with a Woods-Saxon potential form, as much for the real part as for the imaginary one, an adjustment to the experimental data varying only the depth of the imaginary part of the potential is made. A comparison of the results obtained for each projectile is made. (Author)
International Nuclear Information System (INIS)
Dabrowski, H.; Planeta, R.; Djaloeis, A.
1980-01-01
A computer code for the calculation of the optical model parameters, the S matrix and the transmission coefficient, partial and total elastic and absorption cross sections, and the differential elastic scattering cross sections for spinless particles is described. As potential a generalized Woods-Saxon potential is used. Furthermore the Fourier-Bessel series and spline functions are used for the calculation. (HSI) 891 HSI/HSI 892 MKO
Energy Technology Data Exchange (ETDEWEB)
Ruiz S, A. [Facultad de Ciencias, UAEM, Toluca, Estado de Mexico (Mexico); Martinez Q, E.; Aguilera R, E.F.; Murillo O, G.; Lizcano C, D.; Gomez C, A. [Departamento de Aceleradores, ININ, 52750 La Marquesa, Estado de Mexico (Mexico)
2007-07-01
The experimental angular distributions of elastic scattering for the projectiles {sup 6}Li, {sup 7}Be, {sup 8}B in {sup 58}Ni were obtained. Using the Optical model with a Woods-Saxon potential form, as much for the real part as for the imaginary one, an adjustment to the experimental data varying only the depth of the imaginary part of the potential is made. A comparison of the results obtained for each projectile is made. (Author)
Ordering of the 0 d5 /2 and 1 s1 /2 proton levels in light nuclei
Hoffman, C. R.; Kay, B. P.; Schiffer, J. P.
2016-08-01
A survey of the available single-proton data in A ≤17 nuclei was completed. These data, along with calculations using a Woods-Saxon potential, show that the ordering of the 0 d5 /2 and 1 s1 /2 proton orbitals are determined primarily by the proximity of the s -state proton energy to the Coulomb barrier. This is analogous to the dependence of the corresponding neutron orbitals in proximity to the neutron threshold, which was previously discussed.
Phenomenological model of nanocluster in polymer matrix
International Nuclear Information System (INIS)
Oksengendler, B.L.; Turaeva, N.N.; Azimov, J.; Rashidova, S.Sh.
2010-01-01
The phenomenological model of matrix nanoclusters is presented based on the Wood-Saxon potential used in nuclear physics. In frame of this model the following problems have been considered: calculation of width of diffusive layer between nanocluster and matrix, definition of Tamm surface electronic state taking into account the diffusive layer width, receiving the expression for specific magnetic moment of nanoclusters taking into account the interface width. (authors)
Possible existence of backbending in actinide nuclei
International Nuclear Information System (INIS)
Dudek, J.; Nazarewicz, W.; Szymanski, Z.
1982-01-01
The possibilities for the backbending effect to occur in actinide nuclei are studied using the pairing-self-consistent independent quasiparticle method. The Hamiltonian used is that of the deformed Woods-Saxon potential plus monopole pairing term. The results of the calculations explain why there is no backbending in most actinide nuclei and simultaneously suggest that in some light neutron deficient nuclei around Th and 22 Ra a backbending effect may occur
New vistas in superdeformation
Energy Technology Data Exchange (ETDEWEB)
Nazarawicz, W [Joint Inst. for Heavy Ion Research, Oak Ridge, TN (United States)
1992-08-01
Nuclear shape coexistence, or superdeformation, is not a new topic; it dates back to the mid-fifties. In this review, the author concentrates on the following aspects: hyperdeformations, with the Woods-Saxon-Strutinsky total potential energy for thorium-232 as an example; superdeformations far from stability, particularly in mercury isotopes; effective calculation of interactions and effective operators; spin assignments and identical bands. 65 refs., 3 figs.
Equilibrium deformations of single-particle states of odd nuclei of rare earth region
International Nuclear Information System (INIS)
Alikov, B.A.; Tsoj, E.G.; Zuber, K.; Pashkevich, V.V.
1983-01-01
In terms of the Strutinsky shell-correction method using the Woods-Saxon non-spherical potential the energies, quadrupole, and hexadecapole momenta of the ground and excited states of odd-proton nuclei with 61 6 deformation on atomic nuclei non-rotation states energies is discussed. It is shown that account of deformation of α 6 type slightly influences on the quadrupole and hexadecapole deformation value
Wigner-Kirkwood expansion of the phase-space density for half infinite nuclear matter
International Nuclear Information System (INIS)
Durand, M.; Schuck, P.
1987-01-01
The phase space distribution of half infinite nuclear matter is expanded in a ℎ-series analogous to the low temperature expansion of the Fermi function. Besides the usual Wigner-Kirkwood expansion, oscillatory terms are derived. In the case of a Woods-Saxon potential, a smallness parameter is defined, which determines the convergence of the series and explains the very rapid convergence of the Wigner-Kirkwood expansion for average (nuclear) binding energies
Microscopic study of elastic and inelastic ALPHA-nucleus scattering at medium energies
International Nuclear Information System (INIS)
Dao Tien Khoa; Hoang Si Than; Do Cong Cuong; Ngo Van Luyen; Nguyen Ngoc Quynh; Nguyen Tuan Anh
2007-01-01
Analyses of the inelastic α + 12 C scattering at medium energies have indicated that the strength of the Hoyle state (the isoscalar O 2 + excitation at 7.65 MeV in 12 C) seems to exhaust only 7 to 9% of the monopole energy weighted sum rule (EWSR), compared to about 15% of the EWSR extracted from inelastic electron scattering data. The full monopole transition strength predicted by realistic microscopic α-cluster models of the Hoyle state can be shown to exhaust up to 22% of the EWSR. To explore the missing monopole strength in the inelastic α + 12 C scattering, we have performed a fully microscopic folding model analysis of the inelastic α + 12 C scattering at E lab =104 to 240 MeV using the 3-α resonating group wave function of the Hoyle state obtained by Kamimura, and a complex density-dependent M3Y interaction newly parametrized based on the Brueckner Hartree Fock results for nuclear matter. Our folding model analysis has shown consistently that the missing monopole strength of the Hoyle state is not associated with the uncertainties in the analysis of the α + 12 C scattering, but is most likely due to the short lifetime and weakly bound structure of this state which significantly enhances absorption in the exit α + 12 C * (O 2 + ) channel. (author)
Energy Technology Data Exchange (ETDEWEB)
Yuanda, Wang; Xiuming, Bao; Zhiqiang, Mao; Rongfang, Yuan; Keling, Wen; Binyin, Huang; Zhifu, Wang; Shuming, Li; Jianan, Wang; Zuxun, Sun; others, and
1985-11-01
The differential cross sections are measured using 26.0 MeV ..cap alpha.. particle for /sup 58,62/Ni(..cap alpha.., ..cap alpha..) /sup 58,62/Ni and /sup 58,62/Ni(..cap alpha..,p) /sup 61,65/Cu reactions as well as 25.4 MeV ..cap alpha.. particle for /sup 60/Ni(..cap alpha.., ..cap alpha..)/sup 69/Ni and /sup 60/Ni(..cap alpha.., p)/sup 63/Cu reactions. Consistent calculations with optical model and ZR DWBA are made for (..cap alpha.., ..cap alpha..) and (..cap alpha.., p) reactions by using of single, two, three and four nucleon optical potential parameters. For elastic scattering due to the ..cap alpha.. optical potential ambiguities, all the above optical potential can reproduce the experimental angular distributions. However, the single, two and three nucleon potential, including the Baird's mass systematics and the Chang's energy systematics of ..cap alpha.. potentials, obviously can not provide a reasonable fitting with the (..cap alpha..,p) reaction experimental data. Only the results from the four nucleon potential is in good agreement with the (..cap alpha..,p) reaction experimental data. This reveals that in the ..cap alpha..-particle induced transfer reactions, the real depth of the ..cap alpha..-nucleus optical potential should be rather deep.
Study of the elastic scattering of {sup 6}He on {sup 208}Pb at energies around the Coulomb barrier
Energy Technology Data Exchange (ETDEWEB)
Sanchez-Benitez, A.M. [Departamento de Fisica Aplicada, Universidad de Huelva, E-21071 Huelva (Spain); Centre de Recherches du Cyclotron, Universite Catholique de Louvain, B-1348 Louvain-la-Neuve (Belgium); Escrig, D. [Instituto de Estructura de la Materia, CSIC, E-28006 Madrid (Spain); Alvarez, M.A.G.; Andres, M.V. [Departamento de Fisica Atomica, Molecular y Nuclear, Universidad de Sevilla, E-41080 Sevilla (Spain); Angulo, C. [Centre de Recherches du Cyclotron, Universite Catholique de Louvain, B-1348 Louvain-la-Neuve (Belgium); Borge, M.J.G. [Instituto de Estructura de la Materia, CSIC, E-28006 Madrid (Spain); Cabrera, J. [Centre de Recherches du Cyclotron, Universite Catholique de Louvain, B-1348 Louvain-la-Neuve (Belgium); Cherubini, S. [INFN Laboratori Nazionali del Sud, I-95123 Catania (Italy); Demaret, P. [Centre de Recherches du Cyclotron, Universite Catholique de Louvain, B-1348 Louvain-la-Neuve (Belgium); Espino, J.M. [Dept. de Fisica Atomica, Molecular y Nuclear, Universidad de Sevilla, E-41080 Sevilla (Spain); Figuera, P. [INFN Laboratori Nazionali del Sud, I-95123 Catania (Italy); Freer, M. [School of Physics and Astronomy, University of Birmingham, B15 2TT Birmingham (United Kingdom); Garcia-Ramos, J.E. [Departamento de Fisica Aplicada, Universidad de Huelva, E-21071 Huelva (Spain); Gomez-Camacho, J. [Dept. de Fisica Atomica, Molecular y Nuclear, Universidad de Sevilla, E-41080 Sevilla (Spain); Gulino, M. [INFN Laboratori Nazionali del Sud, I-95123 Catania (Italy); Kakuee, O.R. [Van der Graaff Laboratory, Nuclear Research Centre, AEOI, PO Box 14155-1339, Tehran (Iran, Islamic Republic of); Martel, I. [Dept. de Fisica Aplicada, Universidad de Huelva, E-21071 Huelva (Spain)], E-mail: imartel@uhu.es; Metelko, C. [School of Physics and Astronomy, University of Birmingham, B15 2TT Birmingham (United Kingdom); Moro, A.M. [Dept. de Fisica Atomica, Molecular y Nuclear, Universidad de Sevilla, E-41080 Sevilla (Spain)] (and others)
2008-04-15
The elastic scattering of {sup 6}He on {sup 208}Pb has been measured at laboratory energies of 14, 16, 18 and 22 MeV. These data were analyzed using phenomenological Woods-Saxon form factors and optical model calculations. A semiclassical polarization potential was used to study the effect of the Coulomb dipole polarizability. Evidence for long range absorption, partially arising from Coulomb dipole polarizability, is reported. The energy variation of the optical potential was found to be consistent with the dispersion relations which connect the real and imaginary parts of the potential.
Energy Technology Data Exchange (ETDEWEB)
Deshmukh, N.N. [The M.S. University of Baroda, Department of Physics, Faculty of Science, Vadodara (India); Parul Institute of Engineering and Technology, Physics Department, Degree (First Shift), Limda, Waghodia, Vadodara (India); Mukherjee, S.; Appannababu, S.; Patel, D. [The M.S. University of Baroda, Department of Physics, Faculty of Science, Vadodara (India); Nayak, B.K.; Biswas, D.C.; Santra, S.; Mirgule, E.T.; Saxena, A.; Choudhury, R.K. [BARC Mumbai, Nuclear Physics Division, Mumbai (India); Lubian, J.; Gomes, P.R.S. [Universidade Federal Fluminense, Instituto de Fisica, Niteroi (Brazil)
2011-10-15
Elastic-scattering angular distributions of {sup 7}Li on {sup 116}Sn have been measured at different bombarding energies between 18 to 35 MeV. The effects of the weakly bound projectile breakup channel on the bombarding energy dependence of the interaction potential have been investigated. In this work we present the experimental results, along with the theoretical analysis using Woods-Saxon potential to investigate the energy dependence of the interacting polarizing potentials. Total reaction cross-sections are also presented and discussed. (orig.)
International Nuclear Information System (INIS)
Bolotin, Yu.L.; Gonchar, V.Yu.; Chekanov, N.A.
1985-01-01
Coulomb excitation of rotational states induced in heavyion collisions is treated in the framework of the generalized semiclassical approximation. The Hamiltonian of the system under consideration involves not only Coulomb forces (monopole, quadrupole, and hexadecapole) but as well a real nuclear potential in the form of the deformed Woods-Saxon potential. Strong dependence of the excitation probability on the interference between the Coulomb and nuclear interactions is shown. Calculations are carried out for the reaction 40 Ar+ 162 Dy at E=148.6 MeV. The calculated Coulomb excitation probabilities agree satisfactory with the corresponding experimental values
Quantum-mechanical analysis of the VRsup(n) ambiguity in the optical model
International Nuclear Information System (INIS)
Shastry, C.S.
1982-01-01
Using analytical methods and without adopting numerical calculations or semiclassical arguments, it is shown that the well known VRsup(n), n is approximately equal to 2, parameter ambiguity in the neutron-nucleus optical potential can be attributed to the closeness of the Woods-Saxon potential to the corresponding square well inside the nucleus. This parameter ambiguity is absent in individual partial waves but is more apparent in the differential cross section. The analysis is generalised to the proton-nucleus optical model. The present method clearly pinpoints the mathematical origin of the VRsup(n) ambiguity which is difficult to deduce by purely numerical methods. (author)
Systematics of nuclear RMS charge radii
International Nuclear Information System (INIS)
Brown, B.A.; Bronk, C.; Hodgson, P.E.
1984-01-01
The experimental RMS charge radii of isotopic sequences of nuclei are compared with calculations based on the spherical droplet model and spherical single-particle potential models. Harmonic-oscillator, Woods-Saxon and Skyrme Hartree-Fock single-particle potentials are considered. Deviations between experiment and theory are discussed in terms of the model parameters and in terms of the fundamental inadequacies of the models. The experimental B(E2) values connecting the ground states to the lowest 2 + states are used to estimate the increase in RMS radius due to the effects of deformation and zero-point vibrational motion. (author)
Threshold anomaly in the elastic scattering of 6He on 209Bi
International Nuclear Information System (INIS)
Garcia, A. R.; Padron, I.; Lubian, J.; Gomes, P. R. S.; Lacerda, T.; Garcia, V. N.; Gomez-Camacho, A.; Aguilera, E. F.
2009-01-01
The energy dependence of the optical potential for the elastic scattering of 6 He on 209 Bi at near and subbarrier energies is studied. Elastic angular distributions and the reaction cross section were simultaneously fitted by performing some modifications in the ECIS code. A phenomenological optical model potential with the Woods-Saxon form was used. There are signatures that the so called breakup threshold anomaly (BTA) is present in this system having a halo projectile 6 He, as it had been found earlier for systems involving stable weakly bound nuclei. (Author)
Spin rotation function in a microscopic non-relativistic optical model
International Nuclear Information System (INIS)
Bauhoff, W.
1984-01-01
A microscopic optical potential, which is calculated non-relativistically with a density-dependent effective force, is used to calculate cross-section, polarization and spin-rotation function for elastic proton scattering from 40 Ca at 160 MeV and 497 MeV. At 160 MeV, the agreement to the data is comparable to phenomenological fits, and the spin-rotation can be used to distinguish between microscopic and Woods-Saxon potentials. A good fit to the spin-rotation function results at 497 MeV, whereas the polarization data are not well reproduced
(16) {C}16C-elastic scattering examined using several models at different energies
El-hammamy, M. N.; Attia, A.
2018-05-01
In the present paper, the first results concerning the theoretical analysis of the ^{16}C + p reaction by investigating two elastic scattering angular distributions measured at high energy compared to low energy for this system are reported. Several models for the real part of the nuclear potential are tested within the optical model formalism. The imaginary potential has a Woods-Saxon shape with three free parameters. Two types of density distribution and three different cluster structures for ^{16}C are assumed in the analysis. The results are compared with each other as well as with the experimental data to give evidence of the importance of these studied items.
Some aspects of reflection asymmetric deformations in nuclei
International Nuclear Information System (INIS)
Olanders, P.
1984-10-01
The nuclear shape in the intrinsic frame is studied using the Strutinsky method. Various potentials (Nilsson, folded Yukawa and Woods-Saxon) are used for the microscopic part, and the macroscopic part is described as a liquid drop with either a sharp or a smooth surface. Special attention is paid to the possibility of octupole deformed ground states. The consequences of octupole deformations for the rotational behaviour are investigated using the cranking model. It is particularly shown that octupole deformation may supress the backbending in some nuclei. (author)
Cross-sections for neutrino-nucleus interactions on $^{12}C$ and $^{16}O$
Jachowicz, N; Heyde, Kris L G
1998-01-01
We calculate cross sections for neutral current quasi-elastic neutrino-nucleus scattering within a continuum RPA model, based on a Green's function approach. As residual interaction a Skyrme force is used. The unperturbed single particle wave functions are generated using either a Woods-Saxon potential or a Hartree-Fock calculation. These calculations have interesting applications. Neutrinos play an important role in supernova nucleosynthesis. To obtain more information about these processes, cross sections are folded with a Fermi-Dirac distribution with temperatures of approximately 10 9 K.
Jachowicz, N; Heyde, Kris L G; Ryckebusch, J
1999-01-01
We calculate cross sections for neutral current quasi-elastic neutrino-nucleus scattering within a continuum RPA model, based on a Green's function approach. As residual interaction a Skyrme force is used. The unperturbed single particle wave functions are generated using either a Woods-Saxon potential or a Hartree-Fock calculation. These calculations have interesting applications. Neutrinos play an important role in supernova nucleosynthesis. To obtain more information about these processes, cross sections are folded with a Fermi-Dirac distribution with temperatures of approximately 10$^9$ K.
Fusion of the positive Q-value system 36S+48Ca well below the Coulomb barrier
International Nuclear Information System (INIS)
Stefanini, A. M.; Silvestri, R.; Corradi, L.; Fioretto, E.; Guiot, B.; Montagnoli, G.; Beghini, S.; Mason, P.; Scarlassara, F.; Courtin, S.; Haas, F.; Lebhertz, D.; Marginean, N.; Sagaidak, R. N.; Szilner, S.
2008-01-01
The fusion excitation function of 36 S+ 48 Ca has been measured from well above the barrier down to very small cross sections at sub-barrier energies. A steady decrease of the fusion cross sections is observed below the barrier with no pronounced change of slope. The logarithmic derivative saturates and does not reach the value expected for a constant astrophysical S-factor. The S-factor does not show any maximum in the measured energy range. Coupled-channels calculations using a Woods-Saxon potential have been performed
Study of ^{14}C Cluster Decay Half-Lives of Heavy Deformed Nuclei
Shamami, S. Rahimi; Pahlavani, M. R.
2018-01-01
A theoretical model based on deformed Woods-Saxon, Coulomb and centrifugal terms are constructed to evaluate the half-lives for the cluster radioactivity of various super heavy nuclei. Deformation have been applied on all parts of their potential containing nuclear barrier for cluster decay. Also, both parent and daughter nuclei are considered to be deformed. The calculated results of ^{14}C cluster radioactivity half-lives are compared with available experimental data. A satisfactory agreement between theoretical and measured data is achieved. Also, obtained half-lives for each decay family is agreed with Geiger-Nuttall law.
International Nuclear Information System (INIS)
Dudek, J.
1990-01-01
Results of the first calculations aiming at determination of the exotic shape effects at large elongations are presented. After discussing some formal aspects of our generalised approach based on the deformed Woods-Saxon potential, the overall trends in the quantal (shell) effects leading to the deformation driving forces in terms of Y λ=3,μ multipole components are presented. Finally, the nuclei are identified in which (at least at a low spin limit) the predicted exotic shape effects should manifest themselves in the most pronounced way. 10 figs
Elastic scattering of He$sup 3$ AT 20 Mev
Energy Technology Data Exchange (ETDEWEB)
Klingensmith, R. W.; Hausman, H. J.; Ploughe, W. D.
1963-08-15
Absolute differential elastic scattering cross sections were measured for the scattering of 20-Mev /sup 3/He particles from V, Ni, Cu, Rh, /sup 118/Sn, Sm, Yb, and Pb. Where practical the measurements were made at laboratory angles extending from 20 to 170 degrees. The diffraction-like oscillations exhibited by the elastic-to-Coulomb cross section ratios are not highly pronounced. A preliminary optical model analysis was carried out using the HUNTER automatic search code of Drisko and Bassel. A Woods-Saxon potential with Thomas type spin-orbit coupling was considered. Reasonable fits to the data were obtained. (auth)
Identical bands in (even, odd) nuclei as evidence for spectator nucleons
Energy Technology Data Exchange (ETDEWEB)
Schmeing, N C [Atomic Energy of Canada Ltd., Chalk River, ON (Canada). Chalk River Nuclear Labs.
1992-08-01
An explanation is sought for ``identical`` moments of inertia for pairs of rotational bands in superdeformed nuclei differing in particle number. The authors postulate that certain nucleons do not participate in the collective rotation. The energy of superdeformed {sup 152}Dy has been calculated using this model with a deformed Woods-Saxon potential and full mixing of oscillator shells. A significant reduction in energy is achieved when the protons and neutron with asymptotic quantum number N < 4 constitute a nonrotating factor, as compared to the conventional prolate nucleus. 9 refs.
Electromagnetic properties of {sup 181}Ir: evidence of {beta}-stretching
Energy Technology Data Exchange (ETDEWEB)
Garg, U; Reviol, W [Notre Dame Univ., IN (United States). Dept. of Physics; Semmes, P [Tennessee Technological Univ., Cookeville, TN (United States). Dept. of Physics
1992-08-01
The authors calculated the B(M1)/B(E2) ratio in {sup 181}Ir using a fixed-shape particle-rotor model, in order to investigate how sensitive these may be to the nuclear shapes under consideration, and whether there is evidence of coexisting shapes form the electromagnetic data alone. The calculations employed the same Woods-Saxon potential that had been used for TRS (total Routhian surface) and bandhead calculations, and all parameters were taken at their standard values, without adjustment. It was found that the electromagnetic transition rates were well reproduced under the assumption of a single, fixed shape. 17 refs., 4 figs.
Extreme exotic calcium lambda hypernuclei in the relativistic continuum Hartree-Bogoliubov theory
International Nuclear Information System (INIS)
Lv Hongfeng
2008-01-01
Exotic calcium lambda hypernuclei properties with the neutron number of 20-400 by a step of 20 are discussed by employing the relativistic continuum Hartree-Bogoliubov theory with a zero range pairing interaction. The Bethe-Weizsaecker mass formula of a multi-strange system and the Woods-Saxon-type potential of lambda need to be modified for exotic calcium hypernuclei with unusual number of neutrons and lambdas. The possible neutron and lambda limits of exotic Ca lambda hypernuclei are also investigated. (authors)
Global transmission coefficients in Hauser-Feshbach calculations for astrophysics
Energy Technology Data Exchange (ETDEWEB)
Rauscher, T [Inst. fuer Physik, Univ. Basel, Basel (Switzerland)
1998-06-01
The current status of optical potentials employed in the prediction of thermonuclear reaction rates for astrophysics in the Hauser-Feshbach formalism is discussed. Special emphasis is put on {alpha}+nucleus potentials. Further experimental efforts are motivated. (orig.)
Necked-in superdeformed nuclei
International Nuclear Information System (INIS)
Joensson, L.O.
1997-03-01
In this dissertation the possibility of forming superdeformed states related to two connected spheres, having a more or less pronounced neck, is investigated. Detailed Nilsson-Strutinsky calculations with the cranked Woods-Saxon potential and a finite-range liquid drop model are carried out in the 180 Hg region, where superdeformed states related to two overlapping 90 Zr are predicted. Detailed spectroscopic properties are calculated. The effect of the necking degree of freedom on the giant dipole resonance, GDR, is investigated. The calculations are carried out with the Woods-saxon potential for the single-particle states, and the random phase approximation formalism for the phonon states. The residual interaction and coupling constants are determined by requirements of transitional invariance. The lower energy component of the GDR spectrum for superdeformed shapes, corresponding to vibrations along the symmetry axis, is diminished with increasing necking, and the mean energy of the GDR is increased. The folded Yukawa-plus-exponential liquid drop models take into account the finite range of the nuclear force, which is important when elongated and necked-in nuclear shapes are considered. However, it is shown that they are unstable towards higher multipole deformations, and that unphysical shapes are obtained in free minimizations when too high multipole deformations are included. Limits on multipolarity are given as functions of mass number. 9 refs., 4 figs
Energy Technology Data Exchange (ETDEWEB)
Molique, H.
1996-01-19
We present a new method called `PSY-MB`, initially developed in the framework of abstract group theory for the solution of the problem of strongly interacting multi-fermionic systems with particular to systems in an external rotating field. The validity of the new method (PSY-MB) is tested on model Hamiltonians. A detailed comparison between the obtained solutions and the exact ones is performed. The new method is used in the study of realistic nuclear Hamiltonians based on the Woods-Saxon potential within the cranking approximation to study the influence of residual monopole pairing interactions in the rare-earth mass region. In parallel with this new technique we present original results obtained with the Woods-Saxon mean-field and the self-consistent Hartree-Fock approximation in order to investigate such exotic effects as octupole deformations and hexadecapole C{sub 4}-polarizing deformations in the framework of high-spin physics. By developing these three approaches in one single work we prepare the ground for the nuclear structure calculations of the new generation - where the residual two-body interactions are taken into account also in the weak pairing limit. (author). 2370refs.
High spin exotic states and new method for pairing energy
International Nuclear Information System (INIS)
Molique, H.
1996-01-01
We present a new method called 'PSY-MB', initially developed in the framework of abstract group theory for the solution of the problem of strongly interacting multi-fermionic systems with particular to systems in an external rotating field. The validity of the new method (PSY-MB) is tested on model Hamiltonians. A detailed comparison between the obtained solutions and the exact ones is performed. The new method is used in the study of realistic nuclear Hamiltonians based on the Woods-Saxon potential within the cranking approximation to study the influence of residual monopole pairing interactions in the rare-earth mass region. In parallel with this new technique we present original results obtained with the Woods-Saxon mean-field and the self-consistent Hartree-Fock approximation in order to investigate such exotic effects as octupole deformations and hexadecapole C 4 -polarizing deformations in the framework of high-spin physics. By developing these three approaches in one single work we prepare the ground for the nuclear structure calculations of the new generation - where the residual two-body interactions are taken into account also in the weak pairing limit. (author)
International Nuclear Information System (INIS)
Wiktor, S.; Mayer-Boericke, C.; Kiss, A.; Rogge, M; Turek, P.
1980-12-01
The 120,145 and 172.5 MeV α-particle beams from JULIC were used to measure differential cross sections for elastic scattering on 12 C, 24 Mg and 27 Al in the angular range from about 5deg to 70deg (c.m. system). The angular distributions were analysed extensively in terms of the optical model using a variety of potential forms. Apart from the parametrized forms of potential, as Wood-Saxon (WS) or rather (WS)sup(ν) also a model independent representation of potential spline potential was employed. The analysis based on the parametrized forms of the potential made it possible to find the best fit parameter sets, which were than examined on their uniqueness and energy dependence. Emphasis was given to gaining information on the radial shape of the potential. (author)
Solution of the Cox-Thompson inverse scattering problem using finite set of phase shifts
Apagyi, B; Scheid, W
2003-01-01
A system of nonlinear equations is presented for the solution of the Cox-Thompson inverse scattering problem (1970 J. Math. Phys. 11 805) at fixed energy. From a given finite set of phase shifts for physical angular momenta, the nonlinear equations determine related sets of asymptotic normalization constants and nonphysical (shifted) angular momenta from which all quantities of interest, including the inversion potential itself, can be calculated. As a first application of the method we use input data consisting of a finite set of phase shifts calculated from Woods-Saxon and box potentials representing interactions with diffuse or sharp surfaces, respectively. The results for the inversion potentials, their first moments and asymptotic properties are compared with those provided by the Newton-Sabatier quantum inversion procedure. It is found that in order to achieve inversion potentials of similar quality, the Cox-Thompson method requires a smaller set of phase shifts than the Newton-Sabatier procedure.
Solution of the Cox-Thompson inverse scattering problem using finite set of phase shifts
International Nuclear Information System (INIS)
Apagyi, Barnabas; Harman, Zoltan; Scheid, Werner
2003-01-01
A system of nonlinear equations is presented for the solution of the Cox-Thompson inverse scattering problem (1970 J. Math. Phys. 11 805) at fixed energy. From a given finite set of phase shifts for physical angular momenta, the nonlinear equations determine related sets of asymptotic normalization constants and nonphysical (shifted) angular momenta from which all quantities of interest, including the inversion potential itself, can be calculated. As a first application of the method we use input data consisting of a finite set of phase shifts calculated from Woods-Saxon and box potentials representing interactions with diffuse or sharp surfaces, respectively. The results for the inversion potentials, their first moments and asymptotic properties are compared with those provided by the Newton-Sabatier quantum inversion procedure. It is found that in order to achieve inversion potentials of similar quality, the Cox-Thompson method requires a smaller set of phase shifts than the Newton-Sabatier procedure
Elastic scattering of antiprotons from carbon, calcium, and lead at 180 MeV
International Nuclear Information System (INIS)
Garreta, D.; Birien, P.; Bruge, G.; Chaumeaux, A.; Drake, D.M.; Janouin, S.; Legrand, D.; Lemaire, M.C.; Mayer, B.; Pain, J.; Peng, J.C.
1984-01-01
Angular distributions for elastic scattering of 180 MeV antiprotons from 12 C, 40 Ca, and 208 Pb have been measured over a wide angular range with a magnetic spectrometer. In general, microscopic calculations agree fairly well with the data. Optical-model fits with Woods-Saxon parametrization determine the magnitude and the relative strength of the real and imaginary potentials at the nuclear surface. When the shape of the potentials is derived from that of the charge distribution, the depth of the real potential is found to be shallow (30 MeV 0 12 C scattering at 46.8 MeV and with a recent analysis of anti p-atom data. (orig.)
Elastic and inelastic scattering of 18O ions on 12C nuclei
Directory of Open Access Journals (Sweden)
A. T. Rudchik
2009-12-01
Full Text Available Angular distributions of the 12C + 18O elastic and inelastic scattering were measured at the energy Elab(18O = 105 MeV (Ec.m. = 42 MeV. These data and data known from the literature at the energies Ec.m. = 12.9 - 56 МеV were analysed within the optical model and coupled-reactionchannels method. The sets of the Woods-Saxon (12С + 18O-potential parameters were deduced and their energy dependence was studied. It was found the isotopic differences in the (12С + 16O- and (12С + 18O-potentials parameters and in their surface forms. The mechanisms of elastic and inelastic (12С + 18O-scattering and role of transfer reactions were studied.
Detailed determination of the fusion nuclear radius in reactions involving weakly bound projectiles
International Nuclear Information System (INIS)
Gomez Camacho, A.; Aguilera, E. F.; Quiroz, E. M.
2007-01-01
A detailed determination of the fusion radius parameter is performed within the Distorted Wave Born Approximation for reactions involving weakly bound projectiles. Specifically, a simultaneous X 2- analysis of elastic and fusion cross section data is done using a Woods-Saxon potential with volume and surface parts. The volume part is assumed to be responsible for fusion reactions while the surface part for all other direct reactions. It is proved that in order to fit fusion data, particularly for energies below the Coulomb barrier where fusion is enhanced, it is necessary to have a value of around 1.4 fm for the fusion radial parameter of the fusion potential (W F ). This value is much higher than that frequently used in Barrier Penetration models (1.0 fm). The calculations are performed for reactions involving the weakly bound projectile 9 Be with several medium mass targets. (Author)
Multi-quasiparticle high-K isomeric states in deformed nuclei
Directory of Open Access Journals (Sweden)
Xu F. R.
2016-01-01
Full Text Available In the past years, we have made many theoretical investigations on multi-quasiparticle high-K isomeric states. A deformation-pairing-configuration self-consistent calculation has been developed by calculating a configuration-constrained multi-quasiparticle potential energy surface (PES. The specific single-particle orbits that define the high-K configuration are identified and tracked (adiabatically blocked by calculating the average Nilsson numbers. The deformed Woods-Saxon potential was taken to give single-particle orbits. The configuration-constrained PES takes into account the shape polarization effect. Such calculations give good results on excitation energies, deformations and other structure information about multi-quasiparticle high-K isomeric states. Many different mass regions have been investigated.
Statistical density of nuclear excited states
Directory of Open Access Journals (Sweden)
V. M. Kolomietz
2015-10-01
Full Text Available A semi-classical approximation is applied to the calculations of single-particle and statistical level densities in excited nuclei. Landau's conception of quasi-particles with the nucleon effective mass m* < m is used. The approach provides the correct description of the continuum contribution to the level density for realistic finite-depth potentials. It is shown that the continuum states does not affect significantly the thermodynamic calculations for sufficiently small temperatures T ≤ 1 MeV but reduce strongly the results for the excitation energy at high temperatures. By use of standard Woods - Saxon potential and nucleon effective mass m* = 0.7m the A-dependency of the statistical level density parameter K was evaluated in a good qualitative agreement with experimental data.
Analyzing power and differential cross section at 9. 9, 11. 9 and 13. 9 MeV for Ca(n,n)Ca
Energy Technology Data Exchange (ETDEWEB)
Tornow, W.; Woye, E.; Mack, G. (Tuebingen Univ. (Germany, F.R.). Physikalisches Inst.); Floyd, C.E.; Murphy, K.; Guss, P.P.; Wender, S.A.; Byrd, R.C.; Walter, R.L. (Duke Univ., Durham, NC (USA). Dept. of Physics; Triangle Universities Nuclear Lab., Durham, NC (USA))
1982-09-13
The analyzing power and differential cross section for elastic neutron scattering from calcium have been measured at 9.9, 11.9 and 13.9 MeV using the /sup 2/H(d,n)/sup 3/He source reaction and neutron time-of-flight (t.o.f.) techniques to detect the scattered neutrons. Polarized neutron beams were produced via the polarization transfer reaction /sup 2/H(d vector,n vector)/sup 3/He at THETA = 0/sup 0/. The data have been corrected for finite geometry and multiple scattering effects. None of the global neutron-nucleus optical model parameter sets usually referred to in the literature reproduces the present cross-section and analyzing power data. Individual as well as energy-averaged fits of the data resulting from new optical model searches are presented. It is shown that the quoted uncertainties of a recent empirical determination of the real part ..delta..Vsub(C) of the Coulomb correction term are probably underestimated. Our imaginary Coulomb correction term ..delta..Wsub(C) agrees quite well with both a very recent empirical determination and theoretical studies. Although the quality of the fits to the data can be improved by adding iota-dependent potentials to the general optical potential, no definite conclusions can be drawn from the present data as to whether or not iota-dependent potentials are important in neutron-calcium scattering in the energy range investigated. The data have also been analyzed using a Fourier-Bessel series description of the real central optical potential. Comparing the chi/sup 2/ values, the experimental data are better reproduced by the Fourier-Bessel method than by our Woods-Saxon optical model analyses. The Fourier-Bessel potentials obtained show strong deviations from the standard Woods-Saxon shape but are in good agreement with calculations using the nuclear structure approach.
Analyzing power and differential cross section at 9.9, 11.9 and 13.9 MeV for Ca(n,n)Ca
International Nuclear Information System (INIS)
Tornow, W.; Woye, E.; Mack, G.; Clegg, T.
1982-01-01
The analyzing power and differential cross section for elastic neutron scattering from calcium have been measured at 9.9, 11.9 and 13.9 MeV using the 2 H(d,n) 3 He source reaction and neutron time-of-flight (t.o.f.) techniques to detect the scattered neutrons. Polarized neutron beams were produced via the polarization transfer reaction 2 H(d vector,n vector) 3 He at THETA = 0 0 . The data have been corrected for finite geometry and multiple scattering effects. None of the global neutron-nucleus optical model parameter sets usually referred to in the literature reproduces the present cross-section and analyzing power data. Individual as well as energy-averaged fits of the data resulting from new optical model searches are presented. It is shown that the quoted uncertainties of a recent empirical determination of the real part ΔVsub(C) of the Coulomb correction term are probably underestimated. Our imaginary Coulomb correction term ΔWsub(C) agrees quite well with both a very recent empirical determination and theoretical studies. Although the quality of the fits to the data can be improved by adding iota-dependent potentials to the general optical potential, no definite conclusions can be drawn from the present data as to whether or not iota-dependent potentials are important in neutron-calcium scattering in the energy range investigated. The data have also been analyzed using a Fourier-Bessel series description of the real central optical potential. Comparing the chi 2 values, the experimental data are better reproduced by the Fourier-Bessel method than by our Woods-Saxon optical model analyses. The Fourier-Bessel potentials obtained show strong deviations from the standard Woods-Saxon shape but are in good agreement with calculations using the nuclear structure approach. (orig.)
Positive energy Weinberg states for the solution of scattering problems
International Nuclear Information System (INIS)
Rawitscher, G.
1982-01-01
Positive energy Weinberg states are defined and numerically calculated in the presence of a general complex Woods-Saxon potential. The numerical procedure is checked for the limit of a square well potential for which the Weinberg states and the corresponding eigenvalues are known. A finite number M of these (auxiliary) positive energy Weinberg states are then use as a set of basis functions in order to provide a separable approximation of rank M, V/sub M/, to a potential V, and also to the scattering matrix element S which obtains as a result of the presence of V, S/sub M/. Both V/sub M/ and S/sub M/ are obtained by means of algebraic manipulations which involve the matrix elements of V calculated in terms of the auxiliary postive energy Weinberg states Next, expressions are derived which enable one to iteratively correct for the error in V--V/sub M/. These expressions are a modified version of the quasi-particle method of Weinberg. The convergence of S/sub M/ to S, as well as the first order interation of the error in S/sub M/ is examined as a function M for a numerical example which uses a complex Woods-Saxon potential for V and assumes zero angular momentum. With M = 5 and one iteration an error of less than 10% in S is achieved; for M = 8 the error is less than 1%. The method is expected to be useful for the solution of large systems of coupled equations by matrix techniques or when a part of the potential is non-local
Fusion-fission probabilities, cross sections, and structure notes of superheavy nuclei
International Nuclear Information System (INIS)
Kowal, Michał; Cap, Tomasz; Jachimowicz, Piotr; Skalski, Janusz; Siwek-Wilczyńska, Krystyna; Wilczyński, Janusz
2016-01-01
Fusion – fission probabilities in the synthesis of heaviest elements are discussed in the context of the latest experimental reports. Cross sections for superheavy nuclei are evaluated using the “Fusion by Diffusion” (FBD) model. Predictive power of this approach is shown for experimentally known Lv and Og isotopes and predictions given for Z = 119, 120. Ground state and saddle point properties as masses, shell corrections, pairing energies, and deformations necessary for cross-section estimations are calculated systematically within the multidimensional microscopic-macroscopic method based on the deformed Woods-Saxon single-particle potential. In the frame of the FBD approach predictions for production of elements heavier than Z = 118 are not too optimistic. For this reason, and because of high instability of superheavy nuclei, we comment on some structure effects, connected with the K-isomerism phenomenon which could lead to a significant increase in the stability of these systems.
Mass distribution of fission fragments within the Born-Oppenheimer approximation
Energy Technology Data Exchange (ETDEWEB)
Pomorski, K.; Nerlo-Pomorska, B. [M.C.S. University, Department of Theoretical Physics, Lublin (Poland); Ivanyuk, F.A. [Institute for Nuclear Research, Kiev (Ukraine)
2017-03-15
The fission fragments mass-yield of {sup 236} U is obtained by an approximate solution of the eigenvalue problem of the collective Hamiltonian that describes the dynamics of the fission process whose degrees of freedom are: the fission (elongation), the neck and mass-asymmetry modes. The macroscopic-microscopic method is used to evaluate the potential energy surface. The macroscopic energy part is calculated using the liquid drop model and the microscopic corrections are obtained using a Woods-Saxon single-particle levels. The four-dimensional modified Cassini ovals shape parametrization is used to describe the shape of the fissioning nucleus. The mass tensor is taken within a cranking-type approximation. The final fragment mass distribution is obtained by weighting the adiabatic density distribution in the collective space with the neck-dependent fission probability. The neck degree of freedom is found to play a significant role in determining the final fragment mass distribution. (orig.)
Decay study of {sup 246}Fm at SHIP
Energy Technology Data Exchange (ETDEWEB)
Venhart, M. [Comenius University, Department of Nuclear Physics and Biophysics, Bratislava (Slovakia); Slovak Academy of Sciences, Institute of Physics, Bratislava (Slovakia); Hessberger, F.P.; Ackermann, D.; Heinz, S.; Kindler, B.; Kojouharov, I.; Lommel, B.; Mann, R. [GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, Darmstadt (Germany); Antalic, S.; Saro, S. [Comenius University, Department of Nuclear Physics and Biophysics, Bratislava (Slovakia); Gray-Jones, C.; Herzberg, R.D.; Papadakis, P. [University of Liverpool, Department of Physics, Liverpool (United Kingdom); Greenlees, P.T.; Ketelhut, S.; Leino, M. [University of Jyvaeskylae, Department of Physics, Jyvaeskylae (Finland); Hofmann, S. [GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, Darmstadt (Germany); Goethe-Universitaet, Institut fuer Kernphysik, Frankfurt am Main (Germany); Rostron, D. [Goethe-Universitaet, Institut fuer Kernphysik, Frankfurt am Main (Germany); Rudolph, D. [Lund University, Department of Physics, Lund (Sweden); Sulignano, B. [CEA Saclay, DAPNIA/SPhN, Gif/Yvette Cedex (France)
2011-02-15
The decay chain of {sup 246}Fm has been investigated employing the SHIP separator at GSI Darmstadt. The {sup 246}Fm nuclei were produced via the {sup 40}Ar({sup 208}Pb, 2n){sup 246}Fm fusion-evaporation reaction. Improved values of the half-life, T{sub 1/2} = 1.54(4) s, and of the spontaneous fission branching ratio, b{sub SF} = 0.068(6), of {sup 246}Fm were obtained. The {beta}{sup +} /electron capture branching ratio, b{sub EC} = 0.39(3), of {sup 242}Cf was deduced. Possible structures of high-K states in {sup 246}Fm are discussed within the framework of a model calculation based on the Woods-Saxon potential. (orig.)
Behaviour of 144Gd at very high angular momentum. Study of the continuum
International Nuclear Information System (INIS)
Nourreddine, A.
1984-01-01
The specific physical concepts that dictated the choice of 144 Gd for the present high spin study are presented in the first part of this work. The second part describes the various formalisms and techniques used to extract the multiplicities, multipolarities and moments of inertia from continuous γ ray spectra. The third part relates the results of the quasi-continuum γ ray of 144 Gd formed in the fusion-evaporation reaction 120 Sn( 28 Si, 4nγ) with four bombarding energies. A detailed balance of energy and angular momentum of the compound nucleus desexcitation has been given. Finally the evolution of the nuclear shape as a function of spin has been determined from the experimental data and interpreted by a combined micro and macroscopic theoretical calculations using a Woods-Saxon potential [fr
Quasifree electrofission of 238U
International Nuclear Information System (INIS)
Likhachev, V.P.; Deppman, A.; Hussein, M.S.; Mesa, J.; Arruda-Neto, J.D.T.; Carlson, B.V.; Nesterenko, V.O.; Garcia, F.; Rodriguez, O.
2002-01-01
We present the result of a theoretical study of the quasifree electrofission of 238 U. The exclusive differential cross sections for the quasifree scattering reaction stage have been calculated in plane wave impulse approximation, using a macroscopic-microscopic approach for the description of the proton bound states. The nuclear shape was parametrized in terms of Cassinian ovoids. The equilibrium deformation parameters have been calculated by minimizing the total nuclear energy. In the calculation the axially deformed Woods-Saxon single-particle potential was used. The obtained single-particle momentum distributions were averaged over the nuclear symmetry axis direction. The occupation numbers were calculated in the BCS approach. The fissility for the single-hole excited states of the residual nucleus 237 Pa was calculated on the statistical theory grounds, both without taking into account the preequilibrium emission of the particle and with preequilibrium emission in the framework of the exciton model
Role of transitional levels in 237Np (γ,f): Perspectives for studying highly deformed systems
International Nuclear Information System (INIS)
Arruda-Neto, J. D. T.; Mesa, J.; Garcia, F.; Rodriguez, O.; Geraldo, L. P.; Garcia, C.; Guzman, F.; Rodrigues, T. E.; Shtejer, K.; Semmler, R.
2006-01-01
The transition levels at the top of the two 237 Np fission barriers were obtained for the first time by means of the so-called semimicroscopic combined method, which we have developed and implemented. To overcome the difficulties in dealing with large nuclear deformations, we used our developed BARRIER code, which calculates single-particle spectra in a deformed Woods-Saxon potential using a coordinate system based on Cassini ovaloids as nuclear shape parametrization. The results enabled us to describe the experimentally observed near-barrier photofission cross-section structures for 237 Np, as well as a subbarrier shelf, the latter being consistently interpreted in terms of the accumulation of levels at the top of the inner and outer double fission barrier of 237 Np
International Nuclear Information System (INIS)
Nguyen Dinhdang; Nguyen Zuythang
1988-01-01
Using the realistic single-particle energy spectrum obtained in the Woods-Saxon nucleon mean-field potential, we calculate the BCS pairing gap for 58 Ni as a function of temperature taking into account the thermal and particle-number fluctuations. The strength distributions of the electric dipole transitions and the centroids of the isovector giant dipole resonance (IV-GDR) are computed in the framework of the finite-temperature random-phase approximation (RPA) based on the Hamiltonian of the quasiparticle-phonon nuclear model with separate dipole forces. It is shown that the change of the pairing gap at finite temperature can noticeably influence the IV-GDR localisation in realistic nuclei. By taking both thermal and quasiparticle fluctuations in the pairing gap into account the effect of the phase transition from superfluid to normal in the temperature dependence of the IV-GDR centroid is completely smeared out. (author)
On the evaluation of semiclassical nuclear many-particle many-hole level densities
International Nuclear Information System (INIS)
Blin, A.H.; Hiller, B.; Schuck, P.; Yannouleas, C.
1985-10-01
An exact general scheme is described to calculate the m-particle n-hole fermion level densities for an arbitrary single particle Hamiltonian taking into account the Pauli exclusion principle. This technique is applied to obtain level densities of the three dimensional isotropic harmonic oscillator semiclassically in the Thomas-Fermi approach. In addition, we study the l-particle l-hole level density of the Woods-Saxon potential. For the harmonic oscillator we analyze the temperature dependence of the linear response function and the influence of pairing correlations on the l-particle l-hole level density. Finally, a Taylor expansion method of the m-particle n-hole level densities is discussed
Improvement to the gross theory of β decay by inclusion of change in parity
Koura, Hiroyuki; Chiba, Satoshi
2017-06-01
An improvement to the single-particle structure is made to the gross theory, which is a global β -decay model. The gross theory is based on the sum rule of the intensity of the β -decay transition and a strength function. This model provides reasonable results for β -decay rates and delayed neutrons for the entire nuclear mass region. An attempt is made to improve the gross theory of nuclear β decay by considering the change in parity at the single-particle level of ground-state nuclei. In this treatment, the nuclear matrix elements are suppressed when the parity of the single neutron and proton levels is different for the allowed transition. The assignment of parity is performed using the Woods-Saxon-type single-particle potential. The discrepancies from experimental half-lives, which appeared in the vicinity of the magic numbers of neutrons and protons, are systematically improved in the nuclear mass region.
Fluctuations in the thermal superfluid model for heated spherical nuclei
International Nuclear Information System (INIS)
Nguyen Dinhdang; Nguyen Zuythang
1990-01-01
The effect of the non-vanishing thermal pairing gap due to statistical fluctuations is investigated by calculating fluctuations of selected observables such as the energy and particle number fluctuations, the nuclear level density, the level density parameter and the specific heat within the framework of the thermal nuclear superfluid model. In numerical calculations for heated spherical nuclei 58 Ni, 142 Sm and 208 Pb the realistic single-particle energy spectra defined in the Woods-Saxon potential are used. It is found that the results obtained with the non-vanishing thermal average pairing gap can yield an adequate estimate of the true fluctuations in the finite heating non-rotating nuclear systems. (author)
Study of the nuclear structure of {sup 155}Eu; Estudo da estrutura nuclear do {sup 155}Eu
Energy Technology Data Exchange (ETDEWEB)
Genezini, Frederico Antonio
2004-07-01
The {sup 155}Eu nuclide was investigated by the directional angular correlation technique following the {beta} decay of {sup 155}Sm. The angular correlation measurements were carried out using a setup with 4 Ge detectors and a multi parametric data acquisition system. To perform the data analysis a new methodology was developed . The multipole mixing ratios of twenty sixty {gamma}- transitions were determined. Seven of them agreed with the results of earlier angular correlation studies and nineteen obtained for the first time confirmed the multipolarity suggested in earlier electron capture studies. Besides, the spin of the level at 1106.83 keV as well as the parity of the level at 1301.41 keV have also been suggested. The nuclear structure of {sup 155}Eu was discussed successfully in terms of the single particle model using a deformed Woods-Saxon potential plus residual pairing interaction permitting the description of the rotational quasi-proton band heads. (author)
Energy Technology Data Exchange (ETDEWEB)
Morcelle, V.; Lichtenthaeler, R.; Guimaraes, V.; Lepine-Szily, A.; Faria, P.N.; Camargo, O.; Barioni, A.; Mendes Junior, D.R.; Condori, R.P.; Zamora, J.C.; Morais, M.C.; Pires, K.C.C.; Scarduelli, V.; Leistenschneider, E.; Zagatto, V.A.B. [Universidade de Sao Paulo (USP), SP (Brazil); Shorto, J.M.B. [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)
2011-07-01
Full text: Elastic scattering angular distributions and total reaction cross sections of the neutron halo projectile nucleus {sup 6}He on a {sup 58}Ni target at energies around the Coulomb barrier are presented. The measurements were obtained at pelletron accelerator at the University of Sao Paulo (Brazil) and the {sup 6}He radioactive secondary beam has been produced in the RIBRAS system through the {sup 9}Be({sup 7}Li, {sup 6}He){sup 10}B production reaction. The elastic scattering angular distributions obtained at E{sub Lab}= 12.5, 16.5 and 21.0 MeV, have been analysed by using optical model, using the Sao Paulo and Wood-Saxon potentials and the respective total reaction cross sections have been obtained. The total reaction cross sections have been reduced using the Wong formula and the UFF equation and are compared with other stable and unstable systems from the literature. (author)
International Nuclear Information System (INIS)
Werner, T.R.; Dudek, J.
1991-01-01
Microscopic calculations of both the normal and the superdeformed rotational bands have been performed for a number of Rare Earth nuclei. The 'universal' Woods-Saxon potential and the extended Strutinsky method have been used. Excited bands up to a prescribed energy limit E * (usually 2.5 to 3.5 MeV) have been calculated individually by minimizing the corresponding nuclear energies over the quadrupole and hexadecapole deformations. This turns out to be essential, when comparing with experimental results for the known discrete bands. An important influence of the superdeformed neutron (N = 86) shell closure on the microscopically calculated rotational-level densities is illustrated and discussed. (author) 11 refs., 4 figs
Study of the nuclear structure of 155Eu
International Nuclear Information System (INIS)
Genezini, Frederico Antonio
2004-01-01
The 155 Eu nuclide was investigated by the directional angular correlation technique following the β decay of 155 Sm. The angular correlation measurements were carried out using a setup with 4 Ge detectors and a multi parametric data acquisition system. To perform the data analysis a new methodology was developed . The multipole mixing ratios of twenty sixty γ- transitions were determined. Seven of them agreed with the results of earlier angular correlation studies and nineteen obtained for the first time confirmed the multipolarity suggested in earlier electron capture studies. Besides, the spin of the level at 1106.83 keV as well as the parity of the level at 1301.41 keV have also been suggested. The nuclear structure of 155 Eu was discussed successfully in terms of the single particle model using a deformed Woods-Saxon potential plus residual pairing interaction permitting the description of the rotational quasi-proton band heads. (author)
S-factor of 14 N (α, γ)18 F reaction at low-energies
Khalili, H.
2018-06-01
The astrophysical S-factor of the 14 N (α, γ)18 F reaction has been studied at range of bombarding energy 1-1.30 MeV. The 14 N (α, γ)18 F process is important in low energy astrophysics so that a possible source of energy in massive stars which have spent their hydrogen cycle. Using the Wood-saxon potential model, we have been calculated non resonances the astrophysical S-factors for the E 2 transition and our results for Eα = 0.0 MeV is S ≈ 0.5 MeV.b where from experimental is measured to Eα = 0.0 is S ≈ o . 7 MeV.b (Couch et al., 1971) that in comparison with our data good agreement is achieved for the astrophysical S-factor of this process.
Improvements on Semi-Classical Distorted-Wave model
Energy Technology Data Exchange (ETDEWEB)
Sun Weili; Watanabe, Y.; Kuwata, R. [Kyushu Univ., Fukuoka (Japan); Kohno, M.; Ogata, K.; Kawai, M.
1998-03-01
A method of improving the Semi-Classical Distorted Wave (SCDW) model in terms of the Wigner transform of the one-body density matrix is presented. Finite size effect of atomic nuclei can be taken into account by using the single particle wave functions for harmonic oscillator or Wood-Saxon potential, instead of those based on the local Fermi-gas model which were incorporated into previous SCDW model. We carried out a preliminary SCDW calculation of 160 MeV (p,p`x) reaction on {sup 90}Zr with the Wigner transform of harmonic oscillator wave functions. It is shown that the present calculation of angular distributions increase remarkably at backward angles than the previous ones and the agreement with the experimental data is improved. (author)
Disentangling complete and incomplete fusion for 9Be+187Re system at near barrier energies
International Nuclear Information System (INIS)
Kharab, Rajesh; Chahal, Rajiv; Rajiv Kumar
2015-01-01
The breakup of projectile before fusion leads to some unusual fusion mechanisms like incomplete fusion (ICF) and sequential complete fusion (SCF). Experimentally, it is not possible to separate SCF events from direct complete fusion (DCF). However, the complete fusion and incomplete fusion can be measured separately. Theoretically it is very difficult to calculate the complete and incomplete fusion cross section separately using different models. Very recently A. Diaz-Torres has developed a computer code platypus based on classical dynamical model wherein the complete and incomplete fusion cross sections are calculated separately. But this model is found to work very well at energies above the barrier energy. Here we have attempted to extrapolate the results of the code platypus by using simple Wong's formula in conjunction with the energy dependent Woods-Saxon potential (EDWSP) in the below barrier energy region
Lukeš, Jaroslav; Netuka, Ivan; Veselý, Jiří
1988-01-01
Within the tradition of meetings devoted to potential theory, a conference on potential theory took place in Prague on 19-24, July 1987. The Conference was organized by the Faculty of Mathematics and Physics, Charles University, with the collaboration of the Institute of Mathematics, Czechoslovak Academy of Sciences, the Department of Mathematics, Czech University of Technology, the Union of Czechoslovak Mathematicians and Physicists, the Czechoslovak Scientific and Technical Society, and supported by IMU. During the Conference, 69 scientific communications from different branches of potential theory were presented; the majority of them are in cluded in the present volume. (Papers based on survey lectures delivered at the Conference, its program as well as a collection of problems from potential theory will appear in a special volume of the Lecture Notes Series published by Springer-Verlag). Topics of these communications truly reflect the vast scope of contemporary potential theory. Some contributions deal...
International Nuclear Information System (INIS)
Ferreira, P.L.; Tomio, L.
1992-01-01
In this paper, relativistic confining potential models, endowed with bag constants associated to volume energy terms, are investigated. In contrast to the usual bag model, these potential bags are distinguished by having smeared bag surfaces. Based on the dynamical assumptions underlying the fuzzy bag model, these bag constants are derived from the corresponding energy-momentum tensor. Explicit expressions for the single-quark energies and for the nucleon bag constant are obtained by means of an improved analytical version of the saddle-point variational method for the Dirac equation with confining power-law potentials of the scalar plus vector (S + V) or pure scalar (S) type
African Journals Online (AJOL)
big timmy
4Department of Geology, Ekiti State University, Ado-Ekiti, Nigeria. Corresponding ... integrated for the classification of the study area into different groundwater potential zones. .... table is mainly controlled by subsurface movement of water into ...
DEFF Research Database (Denmark)
Mikkelsen, Henrik Hvenegaard; Søgaard, Thomas Friis
2015-01-01
” plays a critical role in relation to Bugkalot men’s construction of hegemonic masculinity and the sustaining of complex egalitarian relations. The Bugkalot have a notoriously violent history; until the late 1970s more than half of the adult men engaged in ritual killings. While most Bugkalot men has...... that can also be used in other contexts to understand how men construct hegemonic masculinity by strategically adopting the interspace of civility and violence.......This article explores the social significance of violence as potentiality and performance among former headhunters. Taking its outset in an ethnographic study of violence and masculinity among the Philippine people known as the Bugkalot, we explore how violence as “performed violent potentiality...
Helms, Lester L
2014-01-01
Potential Theory presents a clear path from calculus to classical potential theory and beyond, with the aim of moving the reader into the area of mathematical research as quickly as possible. The subject matter is developed from first principles using only calculus. Commencing with the inverse square law for gravitational and electromagnetic forces and the divergence theorem, the author develops methods for constructing solutions of Laplace's equation on a region with prescribed values on the boundary of the region. The latter half of the book addresses more advanced material aimed at those with the background of a senior undergraduate or beginning graduate course in real analysis. Starting with solutions of the Dirichlet problem subject to mixed boundary conditions on the simplest of regions, methods of morphing such solutions onto solutions of Poisson's equation on more general regions are developed using diffeomorphisms and the Perron-Wiener-Brelot method, culminating in application to Brownian motion. In ...
DEFF Research Database (Denmark)
Mikkelsen, Henrik Hvenegaard; Friis Søgaard, Thomas
2016-01-01
as ‘performed violent potentiality’ plays a critical role in relation to Bugkalot men’s construction of hegemonic masculinity and the sustaining of complex egalitarian relations. The Bugkalot have a notoriously violent history; until the late 1970s more than half of the adult men engaged in ritual killings...... provide general insights that can also be used in other contexts to understand how men construct hegemonic masculinity by strategically adopting the interspace of civility and violence.......This article explores the social significance of violence as potentiality and performance among former headhunters engaged in ritual killings. Taking its outset in an ethnographic study of violence and masculinity among the Philippine people known as the Bugkalot, we explore how violence...
International Nuclear Information System (INIS)
Hodgson, P.E.
1990-01-01
The effects of nucleon clustering in nuclei are described, with reference to both nuclear structure and nuclear reactions, and the advantages of using the cluster formalism to describe a range of phenomena are discussed. It is shown that bound and scattering alpha-particle states can be described in a unified way using an energy-dependent alpha-nucleus potential. (author)
A global analysis of the elastic 3He scattering in the framework of the optical model
International Nuclear Information System (INIS)
Trost, H.J.
1981-01-01
The elastic scattering of 3 He at projetile energies from 10 MeV to 220 MeV on target nuclei in the mass range 10 to 208 is coherently studied in the framework of the simple optical model. It succeeds to obtain in the whole range a reasonable description by means of the usual Woods-Saxon potentials. This is illustrated by the presentation of a global mass and energy dependent potential. The light target nuclei are included in these systematics without the introduction of any special procedures. The omission of the antisymmetrization by the use of a purely local potential and the spin-orbit interaction have no important influence in the determination of the central potential. The cancelling of the discerte ambiguity is globally guaranted by the presented parametrization. The tradional sum rule 'number of projectile nucleons multiplied by nucleon-nucleus potential is equal to nucleus-nuclear potential' is not fulfilled. Starting from existing theoretical papers the properties of the global 3 He potential can be quantitatively explained. On the base of the 3 He potentials determined here and existing nucleon and deuteron potentials finally an approach to a projectile systematic is indicated. (orig.) [de
Investigation of {sup 17}F+p elastic scattering at near-barrier energies
Energy Technology Data Exchange (ETDEWEB)
El-Azab Farid, M. [Assiut University, Physics Department, Assiut (Egypt); Ibraheem, Awad A. [Al-Azhar University, Physics Department, Assiut (Egypt); King Khalid University, Physics Department, Abha (Saudi Arabia); Al-Hajjaji, Arwa S. [Taiz University, Physics Department, Taiz (Yemen)
2015-10-15
The {sup 17}F +p elastic scattering at two near-barrier energies of 3.5 and 4.3 MeV/nucleon, have been analyzed in the framework of the single folding approach. The folded potentials are constructed by folding the density-dependent (DDM3Y) effective nucleon-nucleon interaction over the nuclear density of the one-proton halo nucleus {sup 17}F. Two versions of the density are considered. In addition, two versions of the one-nucleon knock-on exchange potentials are introduced to construct the real microscopic potentials. The derived potentials supplemented by phenomenological Woods-Saxon imaginary and spin-orbit potentials produced excellent description of the differential elastic scattering cross sections at the higher energy without need to introduce any renormalization. At the lower energy, however, in order to successfully reproduce the data, it is necessary to reduce the strength of the constructed real DDM3Y potential by about 25% of its original value. Furthermore, good agreement with data is obtained using the extracted microscopic DDM3Y potentials for both real and imaginary parts. Moreover, the interesting notch test is applied to investigate the sensitivity of the elastic scattering cross section to the radial distribution of the constructed microscopic potentials. The extracted reaction (absorption) cross sections are, also, investigated. (orig.)
Investigation of 17F+p elastic scattering at near-barrier energies
International Nuclear Information System (INIS)
El-Azab Farid, M.; Ibraheem, Awad A.; Al-Hajjaji, Arwa S.
2015-01-01
The 17 F +p elastic scattering at two near-barrier energies of 3.5 and 4.3 MeV/nucleon, have been analyzed in the framework of the single folding approach. The folded potentials are constructed by folding the density-dependent (DDM3Y) effective nucleon-nucleon interaction over the nuclear density of the one-proton halo nucleus 17 F. Two versions of the density are considered. In addition, two versions of the one-nucleon knock-on exchange potentials are introduced to construct the real microscopic potentials. The derived potentials supplemented by phenomenological Woods-Saxon imaginary and spin-orbit potentials produced excellent description of the differential elastic scattering cross sections at the higher energy without need to introduce any renormalization. At the lower energy, however, in order to successfully reproduce the data, it is necessary to reduce the strength of the constructed real DDM3Y potential by about 25% of its original value. Furthermore, good agreement with data is obtained using the extracted microscopic DDM3Y potentials for both real and imaginary parts. Moreover, the interesting notch test is applied to investigate the sensitivity of the elastic scattering cross section to the radial distribution of the constructed microscopic potentials. The extracted reaction (absorption) cross sections are, also, investigated. (orig.)
Hiroshi Uno
2007-01-01
This paper proposes a new class of potential games, the nested potential games, which generalize the potential games defined in Monderer and Shapley (1996), as well as the pseudo-potential games defined in Dubey et al. (2006). We show that each maximizer of a nested potential is a Nash equilibrium.
International Nuclear Information System (INIS)
Wilk, Philip A.
2001-01-01
SPIT is an adaptation by John Wild [Wild 1988] of a neutron evaporation code that has been in circulation around LBNL and LLNL. It is a program for calculating fusion product cross sections for reactions that de-excite through neutron emission. It was originally written in FORTRAN for the VAX microcomputer. It is related closely to another neutron evaporation code JORPLE written by Jose Alonso [Alonso 1974]. SPIT uses a different set of potentials and does a better job of reproducing the excitation function shapes than JORPLE, though both predict approximately the same excitation peak energy. The main difference [Haynes 1988] between the two programs is that JORPLE uses a standard Coulomb potential and the Woods-Saxon potential, while SPIT uses a Bondorf, Sobel, and Sperber coulomb potential [Bondorf 1974] and the Bass proximity potential [Bass 1974]. Our group, the Heavy Element Nuclear and Radiochemistry Group, here at LBNL has made extensive use of this code for estimating reaction cross sections for experiments that are to be performed at the 88-Inch cyclotron. It requires no calculation parameters aside from the Z and A of the projectile and target nucleus, and this feature has allowed us to use it in a consistent manner for experiments here for over ten years. The cross sections that are calculated with SPIT are consistently within an order of magnitude of those experimentally observed
Directory of Open Access Journals (Sweden)
Xu Y.
2018-01-01
Full Text Available The astrophysical p-process is an important way of nucleosynthesis to produce the stable and proton-rich nuclei beyond Fe which can not be reached by the s- and r-processes. In the present study, the impact of nuclear ingredients, especially the nuclear potential, level density and strength function, to the astrophysical re-action rates of (p,γ, (α,γ, (γ,p, and (γ,α reactions are systematically studied. The calculations are performed basad on the modern reaction code TALYS for about 3000 stable and proton-rich nuclei with 12≤Z≤110. In particular, both of the Wood-Saxon potential and the microscopic folding potential are taken into account. It is found that both the capture and photonuclear reaction rates are very sensitive to the nuclear potential, thus the better determination of nuclear potential would be important to reduce the uncertainties of reaction rates. Meanwhile, the Extreme Light Infrastructure-Nuclear Physics (ELI-NP facility is being developed, which will provide the great opportunity to experimentally study the photonuclear reactions in p-process. Simulations of the experimental setup for the measurements of the photonuclear reactions 96Ru(γ,p and 96Ru(γ,α are performed. It is shown that the experiments of photonuclear reactions in p-process based on ELI-NP are quite promising.
Xu, Y.; Goriely, S.; Balabanski, D. L.; Chesnevskaya, S.; Guardo, G. L.; La Cognata, M.; Lan, H. Y.; Lattuada, D.; Luo, W.; Matei, C.
2018-05-01
The astrophysical p-process is an important way of nucleosynthesis to produce the stable and proton-rich nuclei beyond Fe which can not be reached by the s- and r-processes. In the present study, the impact of nuclear ingredients, especially the nuclear potential, level density and strength function, to the astrophysical re-action rates of (p,γ), (α,γ), (γ,p), and (γ,α) reactions are systematically studied. The calculations are performed basad on the modern reaction code TALYS for about 3000 stable and proton-rich nuclei with 12≤Z≤110. In particular, both of the Wood-Saxon potential and the microscopic folding potential are taken into account. It is found that both the capture and photonuclear reaction rates are very sensitive to the nuclear potential, thus the better determination of nuclear potential would be important to reduce the uncertainties of reaction rates. Meanwhile, the Extreme Light Infrastructure-Nuclear Physics (ELI-NP) facility is being developed, which will provide the great opportunity to experimentally study the photonuclear reactions in p-process. Simulations of the experimental setup for the measurements of the photonuclear reactions 96Ru(γ,p) and 96Ru(γ,α) are performed. It is shown that the experiments of photonuclear reactions in p-process based on ELI-NP are quite promising.
Semimicroscopic analysis of 6Li+28Si elastic scattering at 76 to 318 MeV
Hassanain, M. A.; Anwar, M.; Behairy, Kassem O.
2018-04-01
Using the α-cluster structure of colliding nuclei, the elastic scattering of 6Li+28Si at energies from 76 to 318 MeV has been investigated by the use of the real folding cluster approach. The results of the cluster analysis are compared with those obtained by the CDM3Y6 effective density- and energy-dependent nucleon-nucleon (NN) interaction based upon G -matrix elements of the M3Y-Paris potential. A Woods-Saxon (WS) form was used for the imaginary potential. For all energies and derived potentials, the diffraction region was well reproduced, except at Elab=135 and 154 MeV at large angle. These results suggest that the addition of the surface (DWS) imaginary potential term to the volume imaginary potential is essential for a correct description of the refractive structure of the 6Li elastic scattering distribution at these energies. The energy dependence of the total reaction cross sections and that of the real and imaginary volume integrals is also discussed.
Effective potential for non-convex potentials
International Nuclear Information System (INIS)
Fujimoto, Y.; O'Raifeartaigh, L.; Parravicini, G.
1983-01-01
It is shown that the well-known relationship between the effective potential GAMMA and the vacuum graphs μ of scalar QFT follows directly from the translational invariance of the measure, and that it holds for all values of the fields phi if, and only if, the classical potential is convex. In the non-convex case μ appears to become complex for some values of phi, but it is shown that the complexity is only apparent and is due to the failure of the loop expansion. The effective potential actually remains real and well-defined for all phi, and reduces to μ in the neighbourhood of the classical minima. A number of examples are considered, notably potentials which are spontaneously broken. In particular the mechanism by which a spontaneous breakdown may be generated by radiative corrections is re-investigated and some new insights obtained. Finally, it is shown that the renormalization group equations for the parameters may be obtained by inspection from the effective potential, and among the examples considered are SU(n) fields and supermultiplets. In particular, it is shown that for supermultiplets the effective potential is not only real but positive. (orig.)
International Nuclear Information System (INIS)
Hostachy, J.Y.
1987-01-01
The elastic and inelastic scattering angular distributions of 12 C on the targets 12 C and 208 Pb have been measured at the Laboratoire National Saturne (Saclay) using the spectrometer SPES 1. The data have been analysed in the framework of the optical model with Woods-Saxon potentials. A near side/far side decomposition of the cross-section has provided a more detailed insight into the refraction effects. These analysises show that the strong absorption radius, the reaction cross-section, and consequently the absorption in the surface region, decrease when the incident energy increases, allowing to probe the inner part of the ion-ion potential. The transparency region extends down to a radial internuclei distance of about 3 fm for the 12 C - 12 C system and 8 fm for the 12 C - 208 Pb system. The onset of a decrease of the imaginary potential has been deduced for the two systems. The real potential is also decreasing, but much more rapidly for the 12 C - 208 Pb system than for 12 C- 12 C. We have also developed a microscopic approach in the optical limit of the Glauber theory, including the Pauli-blocking, the Fermi motion and the nucleus finite size effects. For the intermediate energies, the calculations are in fair agreement with the experimental data [fr
Directory of Open Access Journals (Sweden)
H. Mariji
2016-01-01
Full Text Available The nucleon single-particle energies (SPEs of the selected nuclei, that is, O16, Ca40, and Ni56, are obtained by using the diagonal matrix elements of two-body effective interaction, which generated through the lowest-order constrained variational (LOCV calculations for the symmetric nuclear matter with the Aυ18 phenomenological nucleon-nucleon potential. The SPEs at the major levels of nuclei are calculated by employing a Hartree-Fock inspired scheme in the spherical harmonic oscillator basis. In the scheme, the correlation influences are taken into account by imposing the nucleon effective mass factor on the radial wave functions of the major levels. Replacing the density-dependent one-body momentum distribution functions of nucleons, n(k,ρ, with the Heaviside functions, the role of n(k,ρ in the nucleon SPEs at the major levels of the selected closed shell nuclei is investigated. The best fit of spin-orbit splitting is taken into account when correcting the major levels of the nuclei by using the parameterized Wood-Saxon potential and the Aυ18 density-dependent mean field potential which is constructed by the LOCV method. Considering the point-like protons in the spherical Coulomb potential well, the single-proton energies are corrected. The results show the importance of including n(k,ρ, instead of the Heaviside functions, in the calculation of nucleon SPEs at the different levels, particularly the valence levels, of the closed shell nuclei.
Elastic scattering for 16O + 12C at 140 MeV and 218 MeV
International Nuclear Information System (INIS)
Galindo U, A.
1981-01-01
In this work, angular distribution of cross sections have been measured for 12 C( 16 O, 16 O) 12 C at two energies. The measurements were carried out in 0.5 0 intervals between 5 0 -19.5 0 C (lab.) at 140 MeV, 4.5 0 -14.5 0 at 218 MeV. An optical model analysis of these strong structure angular distributions was done. Good fits of the data were obtained using the optical model search code GENOA with a full Woods-Saxon potential form. This yielded parameters subject to considerable ambiguities as it is known to occur for strongly absorbed particles. These ambiguities were explored in detail and it was found that both the real and the imaginary parts present some characteristics that have been found before for the real potential (as Igo relation for continous ambiguities and the fact that potentials with different diffusivities tend to have the same value at the strong absorption radii). It was found, among other results, that the real volume integral, the mean square radius, as well as the total reaction cross section (σsub(r)) cannot be determined unambiguously. A strong correlation was found between σsub(r) and the imaginary diffusivity. A systematic study of how the variation of the potential parameters affects the angular distribution is presented and some features of the diffraction structure of the angular distribution are discussed. (author)
Energy Technology Data Exchange (ETDEWEB)
Morcelle, Viviane; Gomes, P.R.S.; Lubian, J.; Mendes Junior, D.R. [Universidade Federal Fluminense (UFF), Niteroi, RJ (Brazil); Lichtenthaeler, R.; Guimaraes, V.; Lepine-Szily, A.; Camargo, O.; Faria, P.N. de; Gasquez, L.; Morais, M.C.; Condori, R.P.; Pires, K.C.C.; Scarduelli, V. [Universidade de Sao Paulo (USP), SP (Brazil); Barioni, A. [Universidade Federal da Bahia (UFBA), Salvador, BA (Brazil); Shorto, J.M.B. [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Zamora, J.C. [Technische Universitaet Darmstadt (Germany); Aguilera, E.; Martinez-Quiroz, E. [Instituto Nacional de Investigaciones Nucleares (Mexico); Kolata, J.; Jiang, H. [University of Notre Dame, IN (United States); Bechetti, F.D.; Lamm, L.O. [Michigan University, MI (United States); Lizcano, D. [Universidad Autonoma del Estado de Mexico (Mexico)
2012-07-01
Full text: Elastic scattering measurements were performed at energies around the Coulomb barrier at the Tandem Accelerators of the Sao Paulo (USP - Brazil ) and Notre Dame (UND - USA) Universities. The {sup 7}Be is a radioactive nucleus and has been produced by the reaction {sup 6}He({sup 6}Li,{sup 9}Be) and impinged on {sup 27}Al and {sup 197}Au secondary targets using a double superconducting systems RIBRAS ( USP ) and Twinsol (UND). The elastic scattering angular distributions were analyzed through the optical model calculations, using the Woods- Saxon form factors [1] and the Sao Paulo potential [2] to fit the experimental data. The total reaction cross sections were also derived and compared with others presented at the literature for other systems. In addition, a study of the nuclear potential energy dependence has been carried out in this work in the dispersion relation context. Due to the fact that {sup 7}Be has a small breakup threshold energy, the results can provide significant information of the influence of the breakup channel on the reactions involving this projectile. For this purpose, {chi}{sup 2}- data analysis with different kind of potentials were performed to identify the energy dependence of the real (V) and imaginary (W) parts of the potential. [1] L.C. Chamon et al., Phys. Rev. C 66, (2002) 014610. [2] R.D. Wood e D.S. Saxon, Phys. Rev. 95 ( 1954) 577. (author)
International Nuclear Information System (INIS)
Ghodsi, O. N.; Mahmodi, M.; Ariai, J.; O. N. Ghodsi)
2007-01-01
In this paper, the cross-sections of fusion reactions 16 O + 208 Pb, 28 Si + 208 Pb, 40 C + 40 Ca, 40 Ca + 48 Ca, 58 Ni + 58 Ni, and 16 O + 154 Sm at bombarding energies above and near the fusion barrier have been investigated. The fusion cross-sections have been studied by means of the Monte Carlo method and effective soft-core nucleon-nucleon interaction. One adjustable parameter was used in these calculations. This parameter can change the strength and repulsive parts of soft-core potential values. It has to be adjusted, so that the analytical results are in acceptable agreement with the experimental data. In our calculations, we have taken the range of the nucleon-nucleon soft-core interaction to be constant and equal to that of the M3Y-Raid potential. Results show that the higher values for the diffusion parameter in the Woods-Saxon potential obtained from a careful analysis of 16 O + 208 Pb and 28 Si + 208 Pb reactions are due to the many particle effects on the nucleon-nucleon potential. (author)
Directory of Open Access Journals (Sweden)
Ghodsi Omid N.
2007-01-01
Full Text Available In this paper, the cross-sections of fusion reactions 16O + 208Pb, 28Si + 208Pb, 40C + + 40Ca, 40Ca + 48Ca, 58Ni + 58Ni, and 16O + 154Sm at bombarding energies above and near the fusion barrier have been investigated. The fusion cross-sections have been studied by means of the Monte Carlo method and effective soft-core nucleon-nucleon interaction. One adjustable parameter was used in these calculations. This parameter can change the strength and repulsive parts of soft-core potential values. It has to be adjusted, so that the analytical results are in acceptable agreement with the experimental data. In our calculations, we have taken the range of the nucleon-nucleon soft-core interaction to be constant and equal to that of the M3Y-Raid potential. Results show that the higher values for the diffusion parameter in the Woods-Saxon potential obtained from a careful analysis of 16O + 208Pb and 28Si + 208Pb reactions are due to the many particle effects on the nucleon-nucleon potential.
Kansas Data Access and Support Center — This digital spatial data set provides information on the spatial distribution of potential runoff-contributing areas in Kansas. Potential runoff-contributing areas...
Earth Data Analysis Center, University of New Mexico — Crown fire potential was modeled using FlamMap, an interagency fire behavior mapping and analysis program that computes potential fire behavior characteristics. The...
City and County of Durham, North Carolina — This map shows the average household spending potential for retail goods in the United States in 2012. Spending potential data measures household consumer spending...
Generalized Rosenbluth potentials
International Nuclear Information System (INIS)
Hassan, M.H.A.
1977-05-01
It is shown that the coefficients of friction and diffusion of the Balescu-Lenard equation can be derived from two ''generalized Rosenbluth potentials'', which reduce to the standard Rosenbluth potentials if wave effects are neglected. The potentials are evaluated explicitly in the case of Maxwellian field particles. The dominant contribution of wave effects to the potentials is due to the interaction of electron field particles with ion sound waves
International Nuclear Information System (INIS)
Petris, L.
1979-01-01
This report summarizes the results obtained with the nucleon-nucleon potential presented previously for: 1) the deuteron properties and wave function, 2) a Hartree-Fock calculation on O 16 , and 3) the perturbation V-matrix and G-matrix results for the potential in relation to the results of other potentials and to saturation
Energy Technology Data Exchange (ETDEWEB)
Robin, J
2003-12-01
While the superdeformation phenomenon has been observed many times in different mass regions, the excitation energy and angular momentum are not known for most of the superdeformed bands, mainly in the A {approx} 150 mass region. We have thus undertaken the search for and study of linking transitions between super and normal deformed potential wells in the Tb{sup 151} nucleus with the EUROBALL-IV spectrometer based at the subatomic research institute of Strasbourg. This nucleus presents the peculiarity of having an excited superdeformed band identical to the yrast one of Dy{sup 152}, which has recently been linked to normal deformed states. As the Dy{sup 152} nucleus exhibits a shape coexistence in the first potential well, we have also searched for collective rotational bands with prolate but moderate shape, coexisting with the oblate structure of Tb{sup 151}. The discovery of new superdeformed bands in the Tb{sup 151,152} isotopes, the extension to lower and higher spins of the previously known bands, and mean field calculations with a deformed Woods-Saxon potential have contributed to improve our knowledge as well as raise new questions on the orbitals configuration assignments of these bands. (author)
Directory of Open Access Journals (Sweden)
Mehmet Küçükoğlu
2013-06-01
Full Text Available Abstract: In this paper, the experimental data on elastic scattering of the 16O+16O reaction for the energy range 5-10 MeV/nucleon have been analyzed within the optical model (OM formalism by using the phenomenological potential forms in Fresco code. When developing the shape of the nuclear potential for the calculations, we have used the Woods-Saxon (WS or Woods-Saxon squared (WS2 potentials for the imaginary part together with a WS2 type real part. Although most of the previous OM analyses using phenomenological potentials have provided reasonably good fits with the experimental measurements, none of them could completely relate the behavior of the imaginary potential to the energy of the projectile yet. However, we have managed to introduce two analyses that can keep the real potential parameters almost constant and suggest a linear expression for the depth of the imaginary part of the nuclear potential depending on the incidence energy. Thus, 16O+16O system within this wide energy range has been described globally by the optical potentials having a deep, attractive real potential part and a weaker, energy dependent absorptive imaginary potential part. It has been also shown that, our calculations with these potential forms can reproduce the experimental elastic scattering angular distributions successfully and the maxima and minima are predicted correctly for most of the energies. Key words: 16O+16O reaction, optical model, elastic scattering, cross-section, phenomenological potentials. 5-10MeV/nükleon Bölgesinde 16O+16O Esnek Saçılmasının Analizi için Global bir Optik Model Yaklaşımının Tanıtılması Özet: Bu çalışmada 5-10 MeV/nükleon enerji aralığında 16O+16O reaksiyonunun deneysel esnek saçılma verileri, optik model (OM formalizmi altında, Fresco kodunda fenomenolojik potansiyel formları kullanılarak analiz edilmektedir. Hesaplamalar için nükleer potansiyelin şekli oluşturulurken gerçel kısım için Woods-Saxon
Sub-barrier fusion of Si+Si systems
Colucci, G.; Montagnoli, G.; Stefanini, A. M.; Bourgin, D.; Čolović, P.; Corradi, L.; Courtin, S.; Faggian, M.; Fioretto, E.; Galtarossa, F.; Goasduff, A.; Haas, F.; Mazzocco, M.; Scarlassara, F.; Stefanini, C.; Strano, E.; Urbani, M.; Szilner, S.; Zhang, G. L.
2017-11-01
The near- and sub-barrier fusion excitation function has been measured for the system 30Si+30Si at the Laboratori Nazionali di Legnaro of INFN, using the 30Si beam of the XTU Tandem accelerator in the energy range 47 - 90 MeV. A set-up based on a beam electrostatic deflector was used for detecting fusion evaporation residues. The measured cross sections have been compared to previous data on 28Si+28Si and Coupled Channels (CC) calculations have been performed using M3Y+repulsion and Woods-Saxon potentials, where the lowlying 2+ and 3- excitations have been included. A weak imaginary potential was found to be necessary to reproduce the low energy 28Si+28Si data. This probably simulates the effect of the oblate deformation of this nucleus. On the contrary, 30Si is a spherical nucleus, 30Si+30Si is nicely fit by CC calculations and no imaginary potential is needed. For this system, no maximum shows up for the astrophysical S-factor so that we have no evidence for hindrance, as confirmed by the comparison with CC calculations. The logarithmic derivative of the two symmetric systems highlights their different low energy trend. A difference can also be noted in the two barrier distributions, where the high-energy peak present in 28Si+28Si is not observed for 30Si+30Si, probably due to the weaker couplings in last case.
Sub-barrier fusion of Si+Si systems
Directory of Open Access Journals (Sweden)
Colucci G.
2017-01-01
Full Text Available The near- and sub-barrier fusion excitation function has been measured for the system 30Si+30Si at the Laboratori Nazionali di Legnaro of INFN, using the 30Si beam of the XTU Tandem accelerator in the energy range 47 - 90 MeV. A set-up based on a beam electrostatic deflector was used for detecting fusion evaporation residues. The measured cross sections have been compared to previous data on 28Si+28Si and Coupled Channels (CC calculations have been performed using M3Y+repulsion and Woods-Saxon potentials, where the lowlying 2+ and 3− excitations have been included. A weak imaginary potential was found to be necessary to reproduce the low energy 28Si+28Si data. This probably simulates the effect of the oblate deformation of this nucleus. On the contrary, 30Si is a spherical nucleus, 30Si+30Si is nicely fit by CC calculations and no imaginary potential is needed. For this system, no maximum shows up for the astrophysical S-factor so that we have no evidence for hindrance, as confirmed by the comparison with CC calculations. The logarithmic derivative of the two symmetric systems highlights their different low energy trend. A difference can also be noted in the two barrier distributions, where the high-energy peak present in 28Si+28Si is not observed for 30Si+30Si, probably due to the weaker couplings in last case.
International Nuclear Information System (INIS)
Robin, J.
2003-12-01
While the superdeformation phenomenon has been observed many times in different mass regions, the excitation energy and angular momentum are not known for most of the superdeformed bands, mainly in the A ∼ 150 mass region. We have thus undertaken the search for and study of linking transitions between super and normal deformed potential wells in the Tb 151 nucleus with the EUROBALL-IV spectrometer based at the subatomic research institute of Strasbourg. This nucleus presents the peculiarity of having an excited superdeformed band identical to the yrast one of Dy 152 , which has recently been linked to normal deformed states. As the Dy 152 nucleus exhibits a shape coexistence in the first potential well, we have also searched for collective rotational bands with prolate but moderate shape, coexisting with the oblate structure of Tb 151 . The discovery of new superdeformed bands in the Tb 151,152 isotopes, the extension to lower and higher spins of the previously known bands, and mean field calculations with a deformed Woods-Saxon potential have contributed to improve our knowledge as well as raise new questions on the orbitals configuration assignments of these bands. (author)
Nuclear structure information studied through Dirac equation with deformed mean fields
International Nuclear Information System (INIS)
Dudek, J.
2000-01-01
Complete text of publication follows. Relativistic mean-field theory provides a formal expression for the Dirac equation for the nucleonic motion in an atomic nucleus. The 'potentials' within such a formalism are given in terms of the meson fields, the latter obtained through a coupled system of equations of the Klein-Grodon type. Usually the whole system is being solved by using a Hartree approximation by employing an iterative selfonsistent algorithms. On a more phenomenological level one can parametrize the potentials that enter into a Dirac equation rather than obtain the selfconsistently; such a simplification was suggested some time ago by the Munich group. We introduce a Woods-Saxon type parametrisation and verify by a non-linear search routine what are the 'best fit potential parameters' that reproduce the single particle excitations in the double-magic spherical nuclei as well as the band-head properties in some hundreds of deformed nuclei. Next, by introducing a low-energy reduction of the Dirac equation, one may obtain in a natural way a Pauli Schrodinger type equation with a position dependent effective mass. The role of the corresponding term in a description of single particle energies of the nucleons is illustrated and the implications for the cranking equation are discussed in some detail. (author)
Advancing the Theory of Nuclear Reactions with Rare Isotopes: From the Laboratory to the Cosmos
Energy Technology Data Exchange (ETDEWEB)
Elster, Charlotte [Ohio Univ., Athens, OH (United States)
2015-06-01
The mission of the TORUS Topical Collaboration is to develop new methods that will advance nuclear reaction theory for unstable isotopes by using three-body techniques to improve direct-reaction calculations, and, by using a new partial-fusion theory, to integrate descriptions of direct and compound-nucleus reactions. Ohio University concentrates its efforts on the first part of the mission. Since direct measurements are often not feasible, indirect methods, e.g. (d,p) reactions, should be used. Those (d,p) reactions may be viewed as three-body reactions and described with Faddeev techniques. Faddeev equations in momentum space have a long tradition of utilizing separable interactions in order to arrive at sets of coupled integral equations in one variable. While there exist several separable representations for the nucleon-nucleon interaction, the optical potential between a neutron (proton) and a nucleus is not readily available in separable form. For this reason we first embarked in introducing a separable representation for complex phenomenological optical potentials of Woods-Saxon type.
Competition between collective and single particle excitations in nuclear structure description
International Nuclear Information System (INIS)
Petrovici, A.N.
1983-01-01
The microscopic description of the quadrupole collective dynamics in even krypton isotopes is presented. A microscopic calculation of Bohr's collective Hamiltonian is used to describe the collective motion in 76 Kr. A single-particle basis calculated in a deformed Woods-Saxon potential leads to the potential energy surface obtained by the Strutinsky renormalization procedure, and to the inertial functions determined in the cranking model approximation. The collective Schroedinger equation is solved numerically to analyse the low-energy, even parity states in 76 Kr. A good agreement between experiment and theory is obtained without specifically adjusting any parameter in the model for this nucleus. Some results regarding statical and dynamical characteristics of sup(74,78,80)Kr isotopes are also presented. The asymmetric rotor model with admixture of two quasiparticles is used to describe the sup(66,68,70)Ge and the sup(64,66)Zn isotopes. The interplay of collective and single particle motions is further investigated by magnetic moment measurements using the method of integral angular correlations perturbed by recoil into gas. The results involve g-factor measurements for 166 Ho, 68 Ge, 64 Zn, 66 Zn and 68 Ga nuclei. Finally, a discussion of further possible improvements and more general developments of the problems under investigation is given. (author)
Pahlavani, M. R.; Firoozi, B.
2016-09-01
γ-ray transitions from excited states of {}16{{N}} and {}16{{O}} isomers that appear in the γ spectrum of the {}616{{{C}}}10\\to {}716{{{N}}}9\\to {}816{{{O}}}8 beta decay chain are investigated. The theoretical approach used in this research starts with a mean-field potential consisting of a phenomenological Woods-Saxon potential including spin-orbit and Coulomb terms (for protons) in order to obtain single-particle energies and wave functions for nucleons in a nucleus. A schematic residual surface delta interaction is then employed on the top of the mean field and is treated within the proton-neutron Tamm-Dancoff approximation (pnTDA) and the proton-neutron random phase approximation. The goal is to use an optimized surface delta interaction interaction, as a residual interaction, to improve the results. We have used artificial intelligence algorithms to establish a good agreement between theoretical and experimental energy spectra. The final results of the ‘optimized’ calculations are reasonable via this approach.
An improved Thomas--Fermi treatment of nuclei
International Nuclear Information System (INIS)
Swiatecki, W.J.
1992-01-01
I want to tell you about an improved Thomas-Fermi method for calculating shell-averaged nuclear properties, such as density distributions, binding energies, etc. A shell-averaged statistical theory is useful as the macroscopic component of microscopic-macroscopic theories of nuclei, such as the Strutinsky method, as well as in theories of nuclear matter in the bulk, relevant in astrophysical applications. In nuclear physics, as well as in atomic and molecular problems, the following question often has to be answered: you are given a potential well, say a deformed Woods-Saxon potential, into which you put N quantized fermions into the lowest N eigenstates, up to a ''Fermi energy'' To. You square the wave functions of the particles and add them up to get the total density ρ( r → ) = Σ i N |ψ i | 2 . Is there some simple way of estimating ρ( r → ) without going through the misery of numerically solving N partial differential Schroedinger equations for the N particles?
Systematically too low values of the cranking model collective inertia parameters
International Nuclear Information System (INIS)
Dudek, I.; Dudek, W.; Lukasiak-Ruchowska, E.; Skalski, I.
1980-01-01
Deformed Nilsson and Woods-Saxon potentials were employed for generating single particle states used henceforth for calculating the inertia tensor (cranking model and monopole pairing) and the collective energy surfaces (Strutinsky method). The deformation was parametrized in terms of quadrupole and hexadecapole degrees of freedom. The classical energy expression obtained from the inertia tensor and energy surfaces was quantized and the resulting stationary Schroedinger equation was solved using the approximate method. The second Isup(π) = 0 + 2 collective level energies were calculated for the Rare Earth and Actinide nuclei and the results compared with the experimental data. The vibrational level energies agree with the experimental ones much better for spherical nuclei for both single particle potentials; the discrepancies for deformed nuclei overestimate the experimental results by roughly a factor of two. It is argued that coupling of the axially symmetric quadrupole degrees of freedom to non-axial and hexadecapole ones does not affect the conclusions about systematically too low mass parameter values. The alternative explanation of the systematic deviations from the 0 + 2 level energies could be a systematically too high stiffness of the energy surfaces obrained with the Strutinsky method. (orig.)
Low-energy levels calculation for 193Ir
International Nuclear Information System (INIS)
Zahn, Guilherme Soares; Zamboni, Cibele Bugno; Genezini, Frederico Antonio; Mesa-Hormaza, Joel; Cruz, Manoel Tiago Freitas da
2006-01-01
In this work, a model based on single particle plus pairing residual interaction was used to study the low-lying excited states of the 193 Ir nucleus. In this model, the deformation parameters in equilibrium were obtained by minimizing the total energy calculated by the Strutinsky prescription; the macroscopic contribution to the potential was taken from the Liquid Droplet Model, with the shell and paring corrections used as as microscopic contributions. The nuclear shape was described using the Cassinian ovoids as base figures; the single particle energy spectra and wave functions for protons and neutrons were calculated in a deformed Woods-Saxon potential, where the parameters for neutrons were obtained from the literature and the parameters for protons were adjusted in order to describe the main sequence of angular momentum and parity of the band heads, as well as the proton binding energy of 193 Ir. The residual pairing interaction was calculated using the BCS prescription with Lipkin-Nogami approximation. The results obtained for the first three band heads (the 3/2 + ground state, the 1/2 + excited state at E ∼ 73 keV and the the 11/2 - isomeric state at E ∼ 80 keV) showed a very good agreement, but the model so far greatly overestimated the energy of the next band head, a 7/2 - at E ∼ 299 keV. (author)
Neutron densities and the single particle structure of several even-even nuclei from 40Ca to 208Pb
International Nuclear Information System (INIS)
Ray, L.; Hodgson, P.E.
1979-01-01
Previously developed techniques which sum the squares of proton single particle wave functions to obtain nuclear charge densities are applied to the study of neutron distributions in /sup 40,48/Ca, /sup 58,64/Ni, /sup 116,124/Sn, and 208 Pb by comparing to those neutron densities deduced from 800 MeV proton elastic scattering data. The proton and neutron single particle wave functions are derived from a one-body, nonlocal Woods-Saxon binding potential whose parameters are adjusted to give the experimental single particle energies. Empirical spectroscopic factors determine the appropriate occupation probabilities for the single particle levels near the Fermi surface. Proper attention is given to nonorthogonality problems and to the removal of the spurious center-of-mass motion. These semiphenomenological neutron densities are compared to the predictions of the density matrix expansion variant of Hartree-Fock theory and to densities which are empirically deduced from recent 800 MeV polarized proton elastic scattering data. These ''experimental'' neutron distributions are obtained from approximate second order Kerman, McManus, and Thaler optical potential analyses using essentially ''model independent'' neutron densities. Qualitatively good agreement is obtained between the semiphenomenological neutron densities computed here, the density matrix expansion predictions, and the empirical results
International Nuclear Information System (INIS)
Delbar, T.; Gregoire, G.; Paic, G.; Ceuleneer, R.; Michel, F.; Vanderpoorten, R.; Budzanowski, A.; Dabrowski, H.; Freindl, L.; Grotowski, K.; Micek, S.; Planeta, R.; Strzalkowski, A.; Eberhard, K.A.
1978-01-01
Angular distributions for α particle elastic scattering by /sup 40,44/Ca and excitation of the 3.73 MeV 3 - collective state of 40 Ca were measured for incident energies ranging from 40 to 62 MeV. An extensive optical model analysis of these elastic scattering cross sections and other available data, using squared Woods-Saxon form factors, results in potentials with fixed geometry for both real and imaginary parts and depths with smooth energy behavior over a broad incident energy range. These results are discussed in the frame of the semi-classical approximation developed by Brink and Takigawa. The sensitiveness of the calculated elastic scattering cross sections to the real part of the potentials as a function of the projectile-target distance has been investigated by means of a notch test. Distorted-wave Born-approximtion calculations for the excitation of the 3.73 MeV 3 - state of 40 Ca are presented
Coupled-channels analyses for 9,11Li + 208Pb fusion reactions with multi-neutron transfer couplings
Choi, Ki-Seok; Cheoun, Myung-Ki; So, W. Y.; Hagino, K.; Kim, K. S.
2018-05-01
We discuss the role of two-neutron transfer processes in the fusion reaction of the 9,11Li + 208Pb systems. We first analyze the 9Li + 208Pb reaction by taking into account the coupling to the 7Li + 210Pb channel. To this end, we assume that two neutrons are directly transferred to a single effective channel in 210Pb and solve the coupled-channels equations with the two channels. By adjusting the coupling strength and the effective Q-value, we successfully reproduce the experimental fusion cross sections for this system. We then analyze the 11Li + 208Pb reaction in a similar manner, that is, by taking into account three effective channels with 11Li + 208Pb, 9Li + 210Pb, and 7Li + 212Pb partitions. In order to take into account the halo structure of the 11Li nucleus, we construct the potential between 11Li and 208Pb with a double folding procedure, while we employ a Woods-Saxon type potential with the global Akyüz-Winther parameters for the other channels. Our calculation indicates that the multiple two-neutron transfer process plays a crucial role in the 11Li + 208Pb fusion reaction at energies around the Coulomb barrier.
Hasan, Mohammd; Mandal, Bhabani Prasad
2018-04-01
In this paper we introduce the concept of super periodic potential (SPP) of arbitrary order n, n ∈I+, in one dimension. General theory of wave propagation through SPP of order n is presented and the reflection and transmission coefficients are derived in their closed analytical form by transfer matrix formulation. We present scattering features of super periodic rectangular potential and super periodic delta potential as special cases of SPP. It is found that the symmetric self-similarity is the special case of super periodicity. Thus by identifying a symmetric fractal potential as special cases of SPP, one can obtain the tunnelling amplitude for a particle from such fractal potential. By using the formalism of SPP we obtain the close form expression of tunnelling amplitude of a particle for general Cantor and Smith-Volterra-Cantor potentials.
Generalized magnetic Rosenbluth potentials
International Nuclear Information System (INIS)
Hassan, M.H.A.
1977-12-01
It is shown that the coefficients of friction and diffusion of the magnetized Balescu-Lenard equation describing the interaction of ion test particles with electron field particles can be derived from two scalar potentials, which reduce to the potentials derived previously when wave effects are neglected. The parts of the potentials describing ''wave effects'' are evaluated explicitly in the case of Maxwellian electrons and the results are compared with the unmagnetized Rosenbluth potentials. The correction is dominant when eta=Ωsub(e)/ωsub(e)(>)1
Schürmann, Michael
2008-01-01
This volume contains the revised and completed notes of lectures given at the school "Quantum Potential Theory: Structure and Applications to Physics," held at the Alfried-Krupp-Wissenschaftskolleg in Greifswald from February 26 to March 10, 2007. Quantum potential theory studies noncommutative (or quantum) analogs of classical potential theory. These lectures provide an introduction to this theory, concentrating on probabilistic potential theory and it quantum analogs, i.e. quantum Markov processes and semigroups, quantum random walks, Dirichlet forms on C* and von Neumann algebras, and boundary theory. Applications to quantum physics, in particular the filtering problem in quantum optics, are also presented.
Handbook of interatomic potentials
International Nuclear Information System (INIS)
Stoneham, A.M.; Taylor, R.
1981-08-01
This Handbook collects together interatomic potentials for a large number of metals. Most of the potentials describe the interactions of host metal atoms with each other, and these, in some cases, may be applied to solid and liquid metals. In addition, there are potentials (a) for a metallic impurity alloyed with the host, (b) for a small number of chemical impurities in the metal (eg H, O), and (c) for rare-gas impurities, notably He. The Handbook is intended to be a convenient source of potentials for bulk, surface and defect calculations, both static and dynamic. (author)
Examining Management Success Potential.
Quatrano, Louis A.
The derivation of a model of management success potential in hospitals or health services administration is described. A questionnaire developed to assess management success potential in health administration students was voluntarily completed by approximately 700 incoming graduate students in 35 university health services administration programs…
Hershkowitz, N.; Forest, C.; Wang, E. Y.; Intrator, T.
1987-01-01
Nonmonotonic plasma potential structures are a common feature of many double layers and sheaths. Steady state plasma potential wells separating regions having different plasma potentials are often found in laboratory experiments. In order to exist, such structures all must find a solution to a common problem. Ions created by charge exchange or ionization in the region of the potential well are electrostatically confined and tend to accumulate and fill up the potential well. The increase in positive charge should eliminate the well. Nevertheless, steady state structures are found in which the wells do not fill up. This means that it is important to take into account processes which 'pump' ions from the well. As examples of ion pumping of plasma wells, potential dips in front of a positively biased electro collecting anode in a relatively cold, low density multidipole plasma is considered. Pumping is provided by ion leaks from the edges of the potential dip or by oscillating the applied potential. In the former case the two dimensional character of the problem is shown to be important.
International Nuclear Information System (INIS)
Hershkowitz, N.; Forest, C.; Wang, E.Y.; Intrator, T.
1987-01-01
Nonmonotonic plasma potential structures are a common feature of many double layers and sheaths. Steady state plasma potential wells separating regions having different plasma potentials are often found in laboratory experiments. In order to exist, all such structures must find a solution to a common problem. Ions created by charge exchange or ionization in the region of the potential well are electrostatically confined and tend to accumulate and fill up the potential well. The increase in positive charge should eliminate the well. Nevertheless, steady state structures are found in which the wells do not fill up. This means that it is important to take into account processes which pump ions from the well. As examples of ion pumping of plasma wells, potential dips in front of a positively biased electron collecting anode in a relatively cold, low density, multidipole plasma are considered. Pumping is provided by ion leaks from the edges of the potential dip or by oscillating the applied potential. In the former case the two-dimensional character of the problem is shown to be important
International Nuclear Information System (INIS)
Hershkowitz, N.; Forest, C.; Wang, E.Y.; Intrator, T.
1987-01-01
Nonmonotonic plasma potential structures are a common feature of many double layers and sheaths. Steady state plasma potential wells separating regions having different plasma potentials are often found in laboratory experiments. In order to exist, such structures all must find a solution to a common problem. Ions created by charge exchange or ionization in the region of the potential well are electrostatically confined and tend to accumulate and fill up the potential well. The increase in positive charge should eliminate the well, but steady state structures are found in which the wells do not fill up. This means that it is important to take into account processes which 'pump' ions from the well. As examples of ion pumping of plasma wells, potential dips in front of a positively biased electron collecting anode in a relatively cold, low density multidipole plasma are considered. Pumping is provided by ion leaks from the edges of the potential dip or by oscillating the applied potential. In the former case the two dimensional character of the problem is shown to be important. (author)
The potential of renewable energy
International Nuclear Information System (INIS)
Piot, M.
2007-01-01
This article presents and comments on definitions of the potential of renewable forms of energy and, in a second part, takes a look at the potentials mentioned in the energy perspectives published by the Swiss Federal Office of Energy (SFOE). The following potentials are looked at: technical potential, ecological potential, economic potential, exploitable and expected potentials, technical, economic and ecological expansion potentials, potential of particular technologies in Switzerland, exploitable and expected expansion potential. Four scenarios for expansion potential are briefly described
Investigation of neutron-rich rare-earth nuclei including the new isotopes 177Tm and 184Lu
International Nuclear Information System (INIS)
Rykaczewski, K.; Gippert, K.L.; Runte, E.; Schmidt-Ott, W.D.; Tidemand-Petersson, P.; Kurcewicz, W.; Nazarewicz, W.
1989-01-01
Decays of neutron-rich isotopes in the rare-earth region were studied by means of on-line mass separation and β-γ spectroscopy using multinucleon-transfer reactions between beams of 136 Xe (9 and 11.7 MeV/u), 186 W (11.7 and 15 MeV/u) and 238 U (11.4 MeV/u) and targets of nat W and Ta. The higher beam energies appear to be advantageous for the production of such isotopes. Two new isotopes were identified: 177 Tm with a half-life T 1/2 = 85±10/15 s, and 184 Lu with T 1/2 ≅ 18 s. A new 47 s-activity found at A = 171 is tentatively assigned to the decay of the new isotope 171 Ho. The properties of the ground and excited states of neutron-rich lanthanide isotopes are interpreted within the shell model using the deformed Woods-Saxon potential. A change of the ground-state configuration for odd-mass neutron-rich lutetium isotopes from π 7/2 + [404] to π 9/2 - [514] is suggested, this change being due to the influence of a large hexadecapole deformation. The role of a possible isometric state in 180 Lu for the nucleosynthesis of 180m Ta is discussed. (orig.)
Urata, Y.; Hagino, K.; Sagawa, H.
2017-12-01
We discuss the role of pairing antihalo effect in the observed odd-even staggering in reaction cross sections for 30,31,32Ne and 36,37,38Mg isotopes by taking into account the ground-state deformation of these nuclei. To this end, we construct the ground-state density for the Ne,3130 and Mg,3736 nuclei based on a deformed Woods-Saxon potential, while for the 32Ne and 38Mg nuclei we also take into account the pairing correlation using the Hartree-Fock-Bogoliubov method. We demonstrate that, when the one-neutron separation energy is small for the odd-mass nuclei, a significant odd-even staggering still appears even with finite deformation, although the degree of staggering is somewhat reduced compared to the spherical case. This implies that the pairing antihalo effect in general plays an important role in generating the odd-even staggering in reaction cross sections for weakly bound nuclei.
International Nuclear Information System (INIS)
Johnson, C.H.; Horen, D.J.; Mahaux, C.
1987-01-01
The real part of the central neutron-/sup 208/Pb mean field is the sum of a Hartree-Fock component plus a dispersive component. In keeping with theoretical expectations, the Hartree-Fock field is assumed to have a Woods-Saxon shape whose depth decreases exponentially with increasing energy and whose radius and diffuseness are independent of energy. The dispersive component is determined from the imaginary part of the optical-model potential by making use of the dispersion relation which connects these two quantities. The imaginary part is written as the sum of a volume and a surface-peaked contribution. The dispersion relation then implies that the real dispersive contribution is also the sum of volume and surface-peaked components. The parameters of the complex mean field are determined by fitting the available differential and polarization cross sections in the energy domain [4, 40 MeV] and the total cross sections in the domain [1,120 MeV]; these data are contained in previous published or unpublished reports, but new measurements of the total cross sections are presented from 1 to 25 MeV. Good fits to these cross sections, and also to unpublished total cross sections for energies up to 165 MeV, are obtained despite the fact that the number of adjusted parameters is quite small because of our use of the constraint implied by the dispersion relation
Determination of the N=16 Shell Closure at the Oxygen Drip Line
International Nuclear Information System (INIS)
Hoffman, C. R.; Tabor, S. L.; Baumann, T.; Bazin, D.; Schiller, A.; Brown, J.; Williams, T.; Christian, G.; Frank, N.; Peters, W. A.; Thoennessen, M.; DeYoung, P. A.; Mears, P.; Reith, J.; Peaslee, G.; Finck, J. E.; Scott, M. J.; Voss, P. J.; Hinnefeld, J.; Howes, R.
2008-01-01
The neutron unbound ground state of 25 O (Z=8, N=17) was observed for the first time in a proton knockout reaction from a 26 F beam. A single resonance was found in the invariant mass spectrum corresponding to a neutron decay energy of 770 -10 +20 keV with a total width of 172(30) keV. The N=16 shell gap was established to be 4.86(13) MeV by the energy difference between the ν1s 1/2 and ν0d 3/2 orbitals. The neutron separation energies for 25 O agree with the calculations of the universal sd shell model interaction. This interaction incorrectly predicts an 26 O ground state that is bound to two-neutron decay by 1 MeV, leading to a discrepancy between the theoretical calculations and experiment as to the particle stability of 26 O. The observed decay width was found to be on the order of a factor of 2 larger than the calculated single-particle width using a Woods-Saxon potential
Distortion Effects on Trojan Horse Applications
International Nuclear Information System (INIS)
Pizzone, R. G.; Spitaleri, C.; La Cognata, M.; Lamia, L.; Romano, S.; Mukhamedzhanov, A. M.; Blokhintsev, L. D.; Bertulani, C. A.; Irgaziev, B. F.
2011-01-01
The widths of the spectator momentum distributions in several nuclei, which have been used as Trojan Horses, have been obtained as a function of the transferred momentum. Applications of Trojan Horse method will also be discussed. The study of processes relevant for astrophysics involving light nuclei has increased in the last decades due to the development of indirect methods. The present paper will also help to point out the distortion effects which arise at low energies in the study of three-body processes and will suggest some way to by-pass them in Trojan Horse Method (THM) applications. The goal of this paper is to compare the experimental momentum distribution of the spectator in the bound state a = (sx) extracted from the 2 → 3 particles (breakup, or breakup with rearrangement) reactions with the theoretical one. The theoretical momentum distribution has been calculated for the target a = (sx) using the Hulthen potential for a = d and Woods-Saxon one with the standard geometrical parameters, radius r 0 = 1.25 fm and diffuseness a = 0.65 fm, for other nuclei. (author)
Development of the α-decay theory of spherical nuclei by means of the shell model
International Nuclear Information System (INIS)
Holan, S.
1978-01-01
The new results achieved within the α-decay theory of spherical nuclei with a (2)-(5) integral formula, unaffected by arbitrary parameters, taking into account the finite shape of the α particle and using a basis of Woods-Saxon uniparticle functions to describe initial and final nuclei, may be summarized as follows: Through α-width calculations performed for many spherical nuclei it has been proved that experimental classifying of α-transition into favoured and unfavoured transitions as well as the hyperfine structure of the transitions can be theoretically explained if considered the nucleon-nucleon correlations in the description of initial and final nuclei; The absolute values of the theoretical α-widths obtained are about 10 2 times smaller compared to the experimental ones. This might be due to an oversimplified approximation of the α-particle-daughter nucleus interaction potential or either to an inaccuracy of the model functions used in describing nucleus decay in the surface area. (author)
Stochastic Resonance algorithms to enhance damage detection in bearing faults
Directory of Open Access Journals (Sweden)
Castiglione Roberto
2015-01-01
Full Text Available Stochastic Resonance is a phenomenon, studied and mainly exploited in telecommunication, which permits the amplification and detection of weak signals by the assistance of noise. The first papers on this technique are dated early 80 s and were developed to explain the periodically recurrent ice ages. Other applications mainly concern neuroscience, biology, medicine and obviously signal analysis and processing. Recently, some researchers have applied the technique for detecting faults in mechanical systems and bearings. In this paper, we try to better understand the conditions of applicability and which is the best algorithm to be adopted for these purposes. In fact, to get the methodology profitable and efficient to enhance the signal spikes due to fault in rings and balls/rollers of bearings, some parameters have to be properly selected. This is a problem since in system identification this procedure should be as blind as possible. Two algorithms are analysed: the first exploits classical SR with three parameters mutually dependent, while the other uses Woods-Saxon potential, with three parameters yet but holding a different meaning. The comparison of the performances of the two algorithms and the optimal choice of their parameters are the scopes of this paper. Algorithms are tested on simulated and experimental data showing an evident capacity of increasing the signal to noise ratio.
Simultaneous Two-Proton Emission Process of Neutron Deficient Nuclei
International Nuclear Information System (INIS)
Rodrigues, M. M. N.; Duarte, S. B.; Leite, T. N.; Teruya, N.
2011-01-01
In a previous work, we have calculated the one-proton emission rate of nuclei near the proton drip line, by using an analytical barrier parametrization. The calculation is based on the WKB-approximation and half-lives are obtained in good agreement with the existing experimental data for one-proton emitters. Motivated by these results, in present work, we have eliminated the artificial barrier parametrization previously used, constructing a realistic barrier composed by the superposition of a nuclear Wood-Saxon potential form plus the coulomb and centrifugal barrier. The purpose here is to see if the simple WKB-calculation is still able to reproduce recent observed experimental results for two-proton emission from 45 Fe. This decay mode has been observed by Miernik et al., reporting the proton energy distribution and half-life energy dependence for 45 Fe simultaneous 2p-emission. For theoretical determination of the half-life and these energy distributions we evoked a statistical assumption of a pioneering Goldansky's work for discussing simultaneous two-proton emission. We have shown that our calculation reproduce in quite good agreement the energy distribution and is also able to offer good half-life result with an appropriated composition of involved values of the angular momentum decay.
Estimating Total Fusion Cross Sections by Using a Coupled-Channel Method
Energy Technology Data Exchange (ETDEWEB)
Choi, Ki-Seok; Cheoun, Myung-Ki [Soongsil University, Seoul (Korea, Republic of); Kim, K. S. [Korea Aerospace University, Koyang (Korea, Republic of); Kim, T. H.; So, W. Y. [Kangwon National University at Dogye, Samcheok (Korea, Republic of)
2017-01-15
We calculate the total fusion cross sections for the {sup 6}He + {sup 209}Bi, {sup 6}Li + {sup 209}Bi,{sup 9}Be + {sup 208}Pb, {sup 10}Be + {sup 209}Bi, and {sup 11}Li + {sup 208}Pb systems by using a coupled-channel (CC) method and compare the results with the experimental data. In the CC approach for the total fusion cross sections, we exploit a globally determined Wood-Saxon potential with Aky¨uz-Winther parameters and couplings of the ground state to the low-lying excited states in the projectile and the target nuclei. The total fusion cross sections obtained with the CC are compared with those obtained without the CC couplings. The latter approach is tantamount to a one-dimensional barrier penetration model. Finally, our approach is applied to understand new data for the {sup 11}Li+{sup 208}Pb system. Possible ambiguities inherent in those approaches are discussed in detail for further applications to the fusion system of halo and/or neutron-rich nuclei.
International Nuclear Information System (INIS)
Nelson, B.A.
1987-01-01
Ion-confining potentials in the Phaedrus tandem mirror are shown to be enhanced over Boltzmann-relations predicted values by radio-frequency (rf) waves in the ion cyclotron range of frequencies (ICRF). The ICRF enhanced potential is larger in the end cell with a lower passing density. Peak potential values decrease with increasing ion endloss current (or central cell density) for a constant rf capacitor bank voltage, and increase with increasing rf-capacitor bank voltage, for a constant ion endloss value (or central cell density). In fully axisymmetric operation, a potential peak is produced in an end cell by the central-cell rf, (with-out end-cell rf) and is found only in the end cell nearer the central-cell antenna. ICRF enhanced potentials are explained as an equilibrium between the electron-collisional filling-in rate and the electron pumping out rate provided by axial time-varying electric fields. Thermal barrier-like potential structures were found in the transition regions between the central cell and end cells, in the fully axisymmetric Phaedrus. Central-cell ICRF trapping effects combined with end-cell μΔ B forces create and pump the barrier potential wells
International Nuclear Information System (INIS)
Chiu, Hueihuang.
1989-01-01
A theoretical method is being developed by which the structure of a radiation field can be predicted by a radiation potential theory, similar to a classical potential theory. The introduction of a scalar potential is justified on the grounds that the spectral intensity vector is irrotational. The vector is also solenoidal in the limits of a radiation field in complete radiative equilibrium or in a vacuum. This method provides an exact, elliptic type equation that will upgrade the accuracy and the efficiency of the current CFD programs required for the prediction of radiation and flow fields. A number of interesting results emerge from the present study. First, a steady state radiation field exhibits an optically modulated inverse square law distribution character. Secondly, the unsteady radiation field is structured with two conjugate scalar potentials. Each is governed by a Klein-Gordon equation with a frictional force and a restoring force. This steady potential field structure and the propagation of radiation potentials are consistent with the well known results of classical electromagnetic theory. The extension of the radiation potential theory for spray combustion and hypersonic flow is also recommended
National Research Council Canada - National Science Library
Wortzel, Larry
1998-01-01
The People's Republic of China (PRC) is seen by many as an economic powerhouse with the world's largest standing military that has the potential to translate economic power into the military sphere...
Energy Technology Data Exchange (ETDEWEB)
Grundberg, J; Lindstrom, U
1986-10-01
Using the notion of torsion potentials, the duality between antisymmetric tensor fields and scalar fields is discussed. First-order actions with these fields, the connection and the metric as independent variables are presented.
DEFF Research Database (Denmark)
Schjerning, Ole; Rosenzweig, Mary; Pottegård, Anton
2016-01-01
BACKGROUND: Several case reports and epidemiological studies have raised concern about the abuse potential of pregabalin, the use of which has increased substantially over the last decade. Pregabalin is, in some cases, used for recreational purposes and it has incurred attention among drug abusers...... for causing euphoric and dissociative effects when taken in doses exceeding normal therapeutic dosages or used by alternative routes of administration, such as nasal insufflation or venous injection. The magnitude of the abuse potential and the mechanism behind it are not fully known. OBJECTIVE: The aim...... of this study was to present a systematic review of the data concerning the abuse potential of pregabalin. METHODS: We performed a systematic literature search and reviewed the preclinical, clinical and epidemiological data on the abuse potential of pregabalin. RESULTS: We included preclinical (n = 17...
Elderberry: Botany, Horticulture, Potential
Horticultural Review allows extensive reviews of the state of the knowledge on certain topics or crops. Elderberry: Botany, Horticulture, Potential, is outlined with an Introduction, Botany, Horticulture, Propagation, Uses and Conclusion sections. This review compiles literature from around the w...
Supersymmetrically transformed periodic potentials
C, David J. Fernandez
2003-01-01
The higher order supersymmetric partners of a stationary periodic potential are studied. The transformation functions associated to the band edges do not change the spectral structure. However, when the transformation is implemented for factorization energies inside of the forbidden bands, the final potential will have again the initial band structure but it can have bound states encrusted into the gaps, giving place to localized periodicity defects.
International Nuclear Information System (INIS)
Jaqaman, H.R.
1977-01-01
The nucleus--nucleus interaction is studied within the framework of the generator coordinate method that permits an easy incorporation of the full effects of antisymmetrization. It is found that the interaction, as far as the elastic scattering problem is concerned, can be described by a simple effective potential that is equivalent to the original many-body (and hence non-local) problem. The potential is obtained by dividing the wavefunction into a long-range part and a short-range part and requiring the former to satisfy a Schroedinger equation. This enables avoiding dealing with the troublesome short-range part of the wavefunction and provides a direct link with the optical model so that the potential obtained here is equivalent to the real part of the optical potential (the imaginary part is not investigated). The effective potential is found to consist of three parts: an interaction term between the nucleons belonging to different nuclei, a kinetic energy term due to the change in the intrinsic kinetic energy of the system as a result of the antisymmetrization, and finally an l-dependent part. The kinetic energy term is found to be very repulsive and effectively gives a hard core, and is calculated for the α--α and 16 O-- 16 O cases. The full potential is calculated for the α--α case for the S, D, and G partial waves and then used to calculate the corresponding phase shifts that are then compared with experimental results and other microscopic calculations. Finally, some recent results and analyses of fusion and deep inelastic reactions are reviewed that seem to indicate the presence of a hard core in the nucleus--nucleus potential. Such a hard core is present in the potential obtained in the sudden approximation
Overview of interatomic potentials
International Nuclear Information System (INIS)
Bonny, G.; Malerba, L.
2005-12-01
In this report an overview on interatomic potentials is given. This overview is by no means complete and it has merely the intention to give the reader an idea of where interatomic potentials come from, as well as to provide the basic ideas behind some commonly used methods for deriving interatomic potentials for molecular dynamics applications. We start by giving a short introduction about the concept of interatomic potential in the framework of quantum mechanics, followed by a short description of commonly used methods for deriving semi-empirical interatomic potentials. After some short theoretical notions on each method, some practical parameterizations of commonly used potentials are given, including very recent ones. An effort has been made to classify existing approaches within a rational and consequent scheme, which is believed to be of use for a thorough comprehension of the topic. Although these approaches can be used in a variety of different materials, we will only discuss the practical cases of metals. Following this, some widespread ad hoc modification of the general methods are discussed. The report is concluded by a generalization of the methods to multi-component materials, in particular metallic alloys. (author)
Assessing offshore wind potential
International Nuclear Information System (INIS)
Adelaja, Adesoji; McKeown, Charles; Calnin, Benjamin; Hailu, Yohannes
2012-01-01
Quantifying wind potential is a pivotal initial step in developing and articulating a state’s policies and strategies for offshore wind industry development. This is particularly important in the Great Lakes States where lessons from other offshore environments are not directly applicable. This paper presents the framework developed for conducting a preliminary assessment of offshore wind potential. Information on lake bathymetry and wind resources were combined in simulating alternative scenarios of technically feasible turbine construction depths and distance concerns by stakeholders. These yielded estimates of developable offshore wind areas and potential power generation. While concerns about the visibility of turbines from shore reduce the power that can be generated, engineering solutions that increase the depths at which turbines can be sited increase such potential power output. This paper discusses the costs associated with technical limitations on depth and the social costs related to public sentiments about distance from the shoreline, as well as the possible tradeoffs. The results point to a very large untapped energy resource in the Michigan’s Great Lakes, large enough to prompt policy action from the state government. - Highlights: ▶ We build a theoretical framework for modeling offshore wind power production. ▶ Illustration of the impact of technology and social limitations on offshore wind energy development. ▶ Geospatial modeling of the offshore wind potential of the Great Lakes.
International Nuclear Information System (INIS)
Neufeld, W.P.
1984-01-01
Recently, the Trend Analysis Program (TAP) of the American Council of Life Insurance commissioned the Futures Group of Glastonbury, Connecticut, to examine the potential for large-scale catastrophic events in the near future. TAP was specifically concerned with five potential crises: the warming of the earth's atmosphere, the water shortage, the collapse of the physical infrastructure, the global financial crisis, and the threat of nuclear war. We are often unprepared to take action; in these cases, we lose an advantage we might have otherwise had. This is the whole idea behind forecasting: to foresee possibilities and to project how we can respond. If we are able to create forecasts against which we can test policy options and choices, we may have the luxury of adopting policies ahead of events. Rather than simply fighting fires, we have the option of creating a future more to our choosing. Short descriptions of these five potential crises and, in some cases, possible solutions are presented
International Nuclear Information System (INIS)
Warren, J.L.
1990-01-01
The author focuses on wastes considered hazardous under the Resource Conservation and Recovery Act. This chapter discusses wastes that are of interest as well as the factors affecting the quantity of waste considered available for waste reduction. Estimates are provided of the quantities of wastes generated. Estimates of the potential for waste reduction are meaningful only to the extent that one can understand the amount of waste actually being generated. Estimates of waste reduction potential are summarized from a variety of government and nongovernment sources
Directory of Open Access Journals (Sweden)
Jordi Lucero
2009-01-01
Full Text Available This problem was to calculate the path a robot would take to navigate an obstacle field and get to its goal. Three obstacles were given as negative potential fields which the robot avoided, and a goal was given a positive potential field that attracted the robot. The robot decided each step based on its distance, angle, and influence from every object. After each step, the robot recalculated and determined its next step until it reached its goal. The robot's calculations and steps were simulated with Microsoft Excel.
International Nuclear Information System (INIS)
Wilmore, D.; Hodgson, P.E.
1976-01-01
The purpose of this paper is to provide a guide to the use of optical model computer programs to analyse and calculate neutron data. After a brief discussion of the physical basis of the optical model a survey is given of the most widely used optical model and Hauser-Feshbach computer programs. The range of applicability and reliability of the major optical potentials proposed is assessed by comparison with available experimental data and some observations and suggestions are made for the optimum choice of optical potentials for given purposes of neutron data calculations. (author)
Evans, Griffith Conrad
1927-01-01
This book studies fundamental properties of the logarithmic potential and their connections to the theory of Fourier series, to potential theory, and to function theory. The material centers around a study of Poisson's integral in two dimensions and of the corresponding Stieltjes integral. The results are then extended to the integrals in terms of Green's functions for general regions. There are some thirty exercises scattered throughout the text. These are designed in part to familiarize the reader with the concepts introduced, and in part to complement the theory. The reader should know some
DEFF Research Database (Denmark)
Kjærgaard, Søren; Canudas-Romo, Vladimir
2017-01-01
The ‘prospective potential support ratio’ has been proposed by researchers as a measure that accurately quantifies the burden of ageing, by identifying the fraction of a population that has passed a certain measure of longevity, for example, 17 years of life expectancy. Nevertheless......, the prospective potential support ratio usually focuses on the current mortality schedule, or period life expectancy. Instead, in this paper we look at the actual mortality experienced by cohorts in a population, using cohort life tables. We analyse differences between the two perspectives using mortality models...
Deposition potential of polonium
Energy Technology Data Exchange (ETDEWEB)
Heal, H. G.
1948-11-23
The cathodic deposition potential for polonium in concentrations of 10{sup -13} normal and 8 x 10{sup -13} normal, the former being 100-fold smaller than the smallest concentrations previously studied, has been determined. The value is 0.64 volt on the hydrogen scale. Considering the various ways in which the graphs can reasonably be drawn, we consider the maximum possible error to be of the order of +- 0.03 volt. There is apparently no shift of deposition potential between concentrations of 10{sup -8} and 10{sup -13} normal, indicating that the Nernst equation is not applicable in these circumstances.
Energy Technology Data Exchange (ETDEWEB)
Munack, A.; Schroder, O. [Johann Heinrich von Thunen Inst., Braunschweig (Germany); Krahl, J. [Coburg Univ. of Applied Sciences, Coburg (Germany); Bunger, J. [Inst. for Prevention and Occupational Medicine of the German Social Accident Insurance, Ruhr-Univ. Inst., Bochum (Germany)
2010-07-01
This paper discussed the potential of biofuels with particular reference to the situation in Germany and Europe. Emphasis was on technical potential, such as biofuel production, utilization and environmental aspects. The Institute of Agricultural Technology and Biosystems Engineering ran vTI emission tests on diesel engines to evaluate the environmental impacts of biofuels. This testing facility is able to drive heavy-duty diesel engines in both stationary and dynamic test cycles, such as the European ESC and ETC. Additional analyses were conducted to determine the fine and ultra-fine particles, polycyclic aromatic hydrocarbons (PAH), aldehydes, ketones, and the usual regulated exhaust gas compounds. Ames tests were conducted to assess the mutagenic potential of tailpipe emissions. Previous study results showed that neat vegetable oils can render the exhaust high in mutagenic potency. Some of the non-regulated exhaust gas compounds were found to vary nonlinearly with the blend composition. B20 was found to have high mutagenic potential and was subject to sedimentation.
Park, Joseph Sung-Yul
2016-01-01
Language occupies a crucial position in neoliberalism, due to the reimagination of language as commodified skill. This paper studies the role of language ideology in this transformation by identifying a particular ideology that facilitates this process, namely the ideology which views language as pure potential. Neoliberalism treats language as a…
Hooman Dabidian; Mohammed Wafaa Al-Ani; Christopher Hassaan Francke; Ahmed Redwan
2013-01-01
While it will require further political stability and security, tourism in Iraq stands to be a major growth sector. The Iraqi tourism sector is currently underdeveloped and in a state of neglect, due to decades of war, closed regimes and recurrent instability and insecurity. However, as Iraq continues to develop and stabilizes, it can begin to meet its tremendous potential as a global tour...
Development potential for hydropower
International Nuclear Information System (INIS)
Laufer, F.; Groetzinger, S.; Peter, M.; Schmutz, A.
2004-11-01
This comprehensive report for the Swiss Federal Office of Energy (SFOE) takes a look at the potential for the development of hydropower in Switzerland. The report updates the energy perspectives made ten years earlier. An overview of Swiss electricity production and consumption is presented and the proportion provided by hydropower is noted. Figures on installed capacity and import/export quantities are presented and discussed. Technological developments and the economical frameworks involved are discussed, as are regulatory measures that can be taken. Theoretical and technically realisable potentials for increased use of hydropower are discussed. The methods used to do this are examined. Strategies and measures to be taken are listed and discussed. An appendix includes data sheets on power plant modelling, including examples
Scalar Potential Model progress
Hodge, John
2007-04-01
Because observations of galaxies and clusters have been found inconsistent with General Relativity (GR), the focus of effort in developing a Scalar Potential Model (SPM) has been on the examination of galaxies and clusters. The SPM has been found to be consistent with cluster cellular structure, the flow of IGM from spiral galaxies to elliptical galaxies, intergalactic redshift without an expanding universe, discrete redshift, rotation curve (RC) data without dark matter, asymmetric RCs, galaxy central mass, galaxy central velocity dispersion, and the Pioneer Anomaly. In addition, the SPM suggests a model of past expansion, past contraction, and current expansion of the universe. GR corresponds to the SPM in the limit in which a flat and static scalar potential field replaces the Sources and Sinks such as between clusters and on the solar system scale which is small relative to the distance to a Source. The papers may be viewed at http://web.infoave.net/˜scjh/ .
Curtright, Thomas
2011-01-01
Continuous interpolates are described for classical dynamical systems defined by discrete time-steps. Functional conjugation methods play a central role in obtaining the interpolations. The interpolates corrrespond to particle motion in an underlying potential, V. Typically, V has no lower bound and can exhibit switchbacks wherein V changes form when turning points are encountered by the particle. The logistic map is used to illustrate these features.
Exploring Vietnam's oil potential
International Nuclear Information System (INIS)
Anon.
1993-01-01
A brief review is given of the oil production potential in Vietnam. Since Since 1987, the country has been open to foreign investment in offshore exploration but has suffered from a US embargo on trade and economic ties. Nevertheless some exploration has occurred and twenty production sharing contracts with international oil companies has been signed. To date most of the finds have been non-commercial but optimism remains high. (U.K.)
Nonadiabatic Ponderomotive Potentials
International Nuclear Information System (INIS)
Dodin IY, Fisch NJ
2005-01-01
An approximate integral of the Manley-Rowe type is found for a particle moving in a high-frequency field, which may interact resonantly with natural particle oscillations. An effective ponderomotive potential is introduced accordingly and can capture nonadiabatic particle dynamics. We show that nonadiabatic ponderomotive barriers can trap classical particles, produce cooling effect, and generate one-way walls for resonant species. Possible atomic applications are also envisioned
Julija Avakumovic, Jelena Avakumovic
2014-01-01
Potential of businesses is available and relevant developed business opportunities which under certain conditions can affect the results of the business. Those are certain conditions possible exposure of the company. The success of a business depends of the knowledge of these resources and the way how to find the optimum combination of scale, structure and dynamics of available resources by the management of the business.
Sicilian potential biogas production
Directory of Open Access Journals (Sweden)
Antonio Comparetti
2013-09-01
Full Text Available This study is aimed at predicting the Sicilian potential biogas production, using the Organic Fraction of Municipal Solid Waste (OFMSW, animal manure and food industry by-products, in a region where only one biogas plant using MSW and one co-digestion plant are nowadays available. The statistical data about OFMSW, the number of animals bred in medium and large farms and the amounts of by-products of food processing industries were evaluated, in order to compute the Sicilian potential biogas and energy production. The OFMSW produced in Sicily, that is 0.8 million tons ca. per year (37% of MSW, could be used in a bio-reactor, together with other raw materials, for Anaerobic Digestion (AD process, producing biogas and “digestate”. Moreover, 3.03 million tons ca. of manure, collected in medium and large animal husbandry farms (where cows, pigs and poultry are bred, and 350 thousand tons ca. of by-products, collected in food processing industries (pomace from olive oil mills and grape marc from wineries, might be used for AD process. The Sicilian potential biogas production from the AD of the above raw materials is 170.2 millions of m3, that is equal to 1023.4 GWh of energy per year, of which 484 GWh from animal manure, 303 GWh from OFMSW and 236.4 GWh from food industry by-products. The highest biogas production is in the province of Palermo (35.6 millions of m3, Ragusa (30.8 millions of m3 and Catania (22.8 millions of m3, having a potential energy production of 213.8, 185 and 137 GWh, respectively.
Energy Technology Data Exchange (ETDEWEB)
Douici, M.; Allal, N. H.; Fellah, M.; Benhamouda, N.; Oudih, M. R. [Laboratoire de Physique Theorique, Faculte de Physique, USTHB BP 32 El-Alia, 16111 Bab-Ezzouar, Alger (Algeria) and Institut des Sciences et Technologie, Centre Universitaire de Khemis Miliana, Route de Theniet-El-Had, 44225 Khemis-Milia (Algeria); Laboratoire de Physique Theorique, Faculte de Physique, USTHB BP 32 El-Alia, 16111 Bab-Ezzouar, Alger (Algeria) and Centre de Recherche Nucleaire d' Alger, COMENA, BP399 Alger-Gare, Alger (Algeria); Laboratoire de Physique Theorique, Faculte de Physique, USTHB BP 32 El-Alia, 16111 Bab-Ezzouar, Alger (Algeria)
2012-10-20
The particle-number fluctuation effect on the root-mean-square (rms) proton and neutron radii of even-even N Almost-Equal-To Z nuclei is studied in the isovector neutron-proton (np) pairing case using an exact particle-number projection method and the Woods-Saxon model.
Neutron roton pairing effect on some even ven rare-earth proton-rich nuclei
International Nuclear Information System (INIS)
Mokhtari, D.
2004-01-01
The neutron roton pairing effect on some even ven rare-earth proton-rich nuclei is studied. It is taken into account, in the isovector case, within the framework of the generalized Bogoliubov-Valatin transformation, using Woods-Saxon single-particle energies. (author)
Self-consistent description of the isospin mixing
International Nuclear Information System (INIS)
Gabrakov, S.I.; Pyatov, N.I.; Baznat, M.I.; Salamov, D.I.
1978-03-01
The properties of collective 0 + states built of unlike particle-hole excitations in spherical nuclei have been investigated in a self-consistent microscopic approach. These states arise when the broken isospin symmetry of the nuclear shell model Hamiltonian is restored. The numerical calculations were performed with Woods-Saxon wave functions
Compact Polarimetry Potentials
Truong-Loi, My-Linh; Dubois-Fernandez, Pascale; Pottier, Eric
2011-01-01
The goal of this study is to show the potential of a compact-pol SAR system for vegetation applications. Compact-pol concept has been suggested to minimize the system design while maximize the information and is declined as the ?/4, ?/2 and hybrid modes. In this paper, the applications such as biomass and vegetation height estimates are first presented, then, the equivalence between compact-pol data simulated from full-pol data and compact-pol data processed from raw data as such is shown. Finally, a calibration procedure using external targets is proposed.
Thermodynamics extends economics potentials
Energy Technology Data Exchange (ETDEWEB)
Bandura, Alexander V. [Kiev Technical Univ., Dept. of Marketing and Management, Kiev (Ukraine); Brodiansky, Victor M. [Moscow Energy Inst., Dept. of Cryogen Machines, Moscow (Russian Federation)
2001-08-01
In this paper we consider the use of exergy in economic valuation and its correlation with money. Exergy-based determination of production expenses provides a new base for 'natural' price determination. A new macroeconomic dynamics approach based on this correlation is proposed. This method is relatively general because it is not restricted by certain assumptions used in traditional economic analysis. The exergy model of macroeconomic dynamics was tested by utilizing data from the US economy. This test, covering a period of about 25 years, confirms this approach and opens new potentials in economic analysis. (Author)
ICT Enhanced Buildings Potentials
DEFF Research Database (Denmark)
Christiansson, Per
2007-01-01
component systems that are accessed and integrated in the real world of building use in different contexts. The ICT systems may be physically or virtually embedded in the building. Already in 1982 AT&T established the 'intelligent buildings', IB, concept due to marketing reasons and the Informart building...... with focus on virtual building models support, new services and user environment definitions and development, virtual spaces and augmented reality, intelligent building components, application ontologies, and ICT systems integration to illustrate ICT enhanced buildings potentials and R&D needs. ...
Pion nucleus optical potential
International Nuclear Information System (INIS)
Kam, J. de.
1981-01-01
The main goal of the investigations, presented is to establish the contributions to the optical potential, coming from scattering processes which involve 1p-1h nuclear states in the intermediate scattering system. The effects of the Pauli principle corrections and the binding corrections are studied in detail. A phenomenological study of pion absorption effects is also presented. The calculations all concern π- 4 He scattering. The simplicity of the 4 He structure makes the π- 4 He system quite an ideal tool for studying the reaction mechanism. (Auth.)
DEFF Research Database (Denmark)
Kilbourn, Kyle
In the movement from understanding the past towards creating the future design anthropology, as a discipline, will turn from one with archival qualities to one endowed with potentials for change. One challenge facing design anthropology is how to show relevance for theory generation while also in......-as is complemented by designing for as design anthropologists stage design workshops, span knowledge traditions, and make design moves. Reflecting on my own research process, I trace a few research tools that underline the craft of design anthropology....
International Nuclear Information System (INIS)
Araki, H.
1981-01-01
In the framework of the C*-algebra formalism of quantum statistical mechanics, the concept of chemical potential or its vector generalization in the case of an arbitrary (not necessarily abelian) separable compact gauge group (of the first kind) is described as an algebraic label of equilibrium states at a given inverse temperature β. It is mathematically attained by extending a (clustering) KMS state of the gauge-invariant part of a C*-algebra F to a state of F and by examining the KMS property of the extension. (Auth.)
International Nuclear Information System (INIS)
Goldstein, Sheldon; Struyve, Ward
2015-01-01
Non-relativistic de Broglie–Bohm theory describes particles moving under the guidance of the wave function. In de Broglie's original formulation, the particle dynamics is given by a first-order differential equation. In Bohm's reformulation, it is given by Newton's law of motion with an extra potential that depends on the wave function—the quantum potential—together with a constraint on the possible velocities. It was recently argued, mainly by numerical simulations, that relaxing this velocity constraint leads to a physically untenable theory. We provide further evidence for this by showing that for various wave functions the particles tend to escape the wave packet. In particular, we show that for a central classical potential and bound energy eigenstates the particle motion is often unbounded. This work seems particularly relevant for ways of simulating wave function evolution based on Bohm's formulation of the de Broglie–Bohm theory. Namely, the simulations may become unstable due to deviations from the velocity constraint. (paper)
The potentialities of terrorism
International Nuclear Information System (INIS)
Cohen, B.L.
1976-01-01
The potential hazard of terrorists obtaining plutonium and building a nuclear device is examined within the perspective of other terrorist activities. Various sources are quoted on the possibility of a terrorist group having the resources, including skilled personnel, to build a bomb. The potential damage engendered by such a device is hypothesized to be less than that of many other terrorist actions which could be easily accomplished. Other activities, poison or nerve gas, gasoline dropped on a football stadium, destruction of a large dam, poisoning food or water supply and armed action against a tanker carrying liquefied natural gas, are cited as examples of terrorist incidents more devastating than building a crude plutonium bomb. Resistance to blackmail strategies is seen as the only reliable way to thwart their activities in the long run. Although plutonium must be guarded carefully, it is demonstrated as being far from the only or most devastating means of blackmail. It is concluded that the threat of terrorist activities is being used by anti-nuclear groups to support emotionally based dislike of nuclear power. (J.T.A.)
Cosmology with exponential potentials
International Nuclear Information System (INIS)
Kehagias, Alex; Kofinas, Georgios
2004-01-01
We examine in the context of general relativity the dynamics of a spatially flat Robertson-Walker universe filled with a classical minimally coupled scalar field φ of exponential potential V(φ) ∼ exp(-μφ) plus pressureless baryonic matter. This system is reduced to a first-order ordinary differential equation for Ω φ (w φ ) or q(w φ ), providing direct evidence on the acceleration/deceleration properties of the system. As a consequence, for positive potentials, passage into acceleration not at late times is generically a feature of the system for any value of μ, even when the late-times attractors are decelerating. Furthermore, the structure formation bound, together with the constraints Ω m0 ∼ 0.25 - 0.3, -1 ≤ w φ0 ≤ -0.6, provides, independently of initial conditions and other parameters, the necessary condition 0 N , while the less conservative constraint -1 ≤ w φ ≤ -0.93 gives 0 N . Special solutions are found to possess intervals of acceleration. For the almost cosmological constant case w φ ∼ -1, the general relation Ω φ (w φ ) is obtained. The generic (nonlinearized) late-times solution of the system in the plane (w φ , Ω φ ) or (w φ , q) is also derived
Evaluation of hydrocarbon potential
International Nuclear Information System (INIS)
Cashman, P.H.; Trexler, J.H. Jr.
1992-01-01
Task 8 is responsible for assessing the hydrocarbon potential of the Yucca Mountain vincinity. Our main focus is source rock stratigraphy in the NTS area in southern Nevada. (In addition, Trexler continues to work on a parallel study of source rock stratigraphy in the oil-producing region of east central Nevada, but this work is not funded by Task 8.) As a supplement to the stratigraphic studies, we are studying the geometry and kinematics of deformation at NTS, particularly as these pertain to reconstructing Paleozoic stratigraphy and to predicting the nature of the Late Paleozoic rocks under Yucca Mountain. Our stratigraphic studies continue to support the interpretation that rocks mapped as the open-quotes Eleana Formationclose quotes are in fact parts of two different Mississippian units. We have made significant progress in determining the basin histories of both units. These place important constraints on regional paleogeographic and tectonic reconstructions. In addition to continued work on the Eleana, we plan to look at the overlying Tippipah Limestone. Preliminary TOC and maturation data indicate that this may be another potential source rock
International Evoked Potentials Symposium
1980-01-01
The past decade has seen great progress in the measurement of evoked potentials in man; a steady increase in our understanding of their charac teristics, their origins and their usefulness; and a growing application in the field of clinical diagnosis. The topic is a truly multidisciplinary one. Important research contributions have been made by workers of many different backgrounds and clinical applications span the specialities. This book represents a revised and updated version of the work originally presented at the international evoked potential symposium held in Nottingham 4-6 1978. The Nottingham Symposium provided a forum for a state-of-the-art discussion amongst workers from many different disciplines and from many different countries. For each major topic in the field an expert review set the scene for discussion of current research presentations. This format is retained in the book: the chapters in Part A provide the context in which the research presented in Part B is set. The task of selecting m...
Radiosensitizers: rationale and potential
International Nuclear Information System (INIS)
Brown, J.M.
1981-01-01
This paper briefly reviews agents that are capable of sensitizing hypoxic cells to radiation and chemotherapeutic agents. The first part is a synopsis of the development of hypoxic radiosensitizers, which concludes that misonidazole can be effective against human tumors. Unfortunately, neurotoxicity limits its effectiveness in humans because the dose that can be given in conjunction with daily fractionated radiation is five to ten times lower than is required for full radiosensitization of the hypoxic cells. The second part covers our recent efforts to develop a drug that does not produce such limiting neurotoxicity. The primary rationale of our program was to synthesize a drug with a short plasma half-life that was too hydrophilic to cross the blood-brain barrier but was able to penetrate tumors and radiosensitize hypoxic cells. From this program, a new drug, SR-2508, has been found that is as efficient as misonidazole in its radiosensitizing ability, but is four to ten times less toxic. Finally, the potential of radiosensitizers not only as agents that can sensitize tumor cells to radiation, but also as agents that can specifically sensitize tumors to chemotherapeutic agents, is discussed. In addition, these drugs may be potential cytotoxic agents that produce toxicity only in solid tumors
Pandurovic, Mila
2017-01-01
The CLICdp is an international collaboration that investigates the physics potential of the Compact Linear Collider (CLIC) and performs research and development of the CLIC detector. CLIC is a future multi-TeV linear electron-positron collider, designed to cover a physics program of the Standard model physics, with the emphasis on Higgs and top as well as to address the wide range of open questions of the phenomena beyond the Standard model with high precision. The CLIC is designed to be build and operated at three discrete energy stages, sort(s) = 380 GeV, 1.5 and 3.0 TeV, which are optimized for the foreseen physics program. In this talk the CLIC accelerator, detector and experimental environment of CLIC will be presented, as well as, the number of the full-simulation measurements in the Higgs, top and beyond Standard model sector, presenting the capabilities of CLIC for high precision measurements.
The effective nuclear potential
International Nuclear Information System (INIS)
Skyrme, T.H.R.
1994-01-01
An empirical analyses is made of the mean effective internucleon potential required in the shell-model description of nuclei, allowing for the presence of many-body effects as suggested by current theory. A consistent description is found in which the effective two-body interaction acts almost entirely in even states, and the many-body effects are simulated by a repulsive three-body contact interaction. The strength of the two-body interaction is consistent with that expressed by the free scattering matrix of the two-nucleon system, and that of the three-body interaction with the 'rearrangement energy' calculated in the many-body theory. (author). 21 refs, 2 figs, 7 tabs
Potential for nuclear terrorism
International Nuclear Information System (INIS)
Jenkins, B.M.
1977-05-01
The question of whether or not terrorists will ''go nuclear'' is discussed. It is possible, although there is no historical evidence that any criminal or terrorist group ever made any attempt to acquire nuclear material for use in an explosive or dispersal device. In terms of intentions, psychotics are potential nuclear terrorists, but in terms of capabilities, they are the farthest away from being able to acquire a nuclear weapon. The history of nuclear incidents in the U.S. and abroad is reviewed. As the nuclear industry expands, the number of low-level incidents (bomb threats, pilferage, etc.) will increase also, but not necessarily escalate to more serious incidents. Terrorists may ''go nuclear'' solely for the publicity value; nuclear hoaxes may be attenpted. Nuclear terrorism seems more attractive as a threat than as an action. But the nature of the threat may change in the future, and the danger of imitation of a successful nuclear terrorist act is pointed out
Corrosion potential analysis system
Kiefer, Karl F.
1998-03-01
Many cities in the northeastern U.S. transport electrical power from place to place via underground cables, which utilize voltages from 68 kv to 348 kv. These cables are placed in seamless steel pipe to protect the conductors. These buried pipe-type-cables (PTCs) are carefully designed and constantly pressurized with transformer oil to prevent any possible contamination. A protective coating placed on the outside diameter of the pipe during manufacture protects the steel pipe from the soil environment. Notwithstanding the protection mechanisms available, the pipes remain vulnerable to electrochemical corrosion processes. If undetected, corrosion can cause the pipes to leak transformer oil into the environment. These leaks can assume serious proportions due to the constant pressure on the inside of the pipe. A need exists for a detection system that can dynamically monitor the corrosive potential on the length of the pipe and dynamically adjust cathodic protection to counter local and global changes in the cathodic environment surrounding the pipes. The northeastern United States contains approximately 1000 miles of this pipe. This milage is critical to the transportation and distribution of power. So critical, that each of the pipe runs has a redundant double running parallel to it. Invocon, Inc. proposed and tested a technically unique and cost effective solution to detect critical corrosion potential and to communicate that information to a central data collection and analysis location. Invocon's solution utilizes the steel of the casing pipe as a communication medium. Each data gathering station on the pipe can act as a relay for information gathered elsewhere on the pipe. These stations must have 'smart' network configuration algorithms that constantly test various communication paths and determine the best and most power efficient route through which information should flow. Each network station also performs data acquisition and analysis tasks that ultimately
Pseudo potentials and model potentials in atomic collisions
International Nuclear Information System (INIS)
Reyes, O.; Jouin, H.; Fuentealba, P.
1988-01-01
In this work, it is discussed the main differences between the use of pseudo-potentials and model potentials in collision problems . It is shown the potential energy curves for distinct systems obtained with both kinds of potentials. (A.C.A.S.) [pt
Bioremedication: Potentials and pitfalls
International Nuclear Information System (INIS)
Nichols, A.B.
1992-01-01
The three main types of marine oil spill bioremediation involve fertilizers, seeding, and open-water applications. Fertilizers contain nutrients that trigger the growth of indigenous oil-degrading microorganisms. Seeding involves adding exogenous microbes to an oiled environment to promote increased biodegradation rates. The effectiveness of using either seeding or fertilizers in the open ocean has not been well established and most of the scientific community and many oil professionals remain skeptical about the utility of bioremediation at sea because rigorously controlled and documented experiments have not yet been done. Several companies have advocated using bioremediation for open ocean oil spills, but they have not yet produced convincing evidence that their products work as claimed. A potentially significant problem at sea is keeping the microorganisms in contact with the oil long enough for degradation to occur. The jury is still out regarding regulatory and public acceptance of bioremediation as a technique to clean up oil spills in general. Commercialization of bioremediation products is hindered by lack of protocols for testing and approval, although efforts are underway to devise such mechanisms
Quantum potentiality revisited
Jaeger, Gregg
2017-10-01
Heisenberg offered an interpretation of the quantum state which made use of a quantitative version of an earlier notion, , of Aristotle by both referring to it using its Latin name, potentia, and identifying its qualitative aspect with . The relationship between this use and Aristotle's notion was not made by Heisenberg in full detail, beyond noting their common character: that of signifying the system's objective capacity to be found later to possess a property in actuality. For such actualization, Heisenberg required measurement to have taken place, an interaction with external systems that disrupts the otherwise independent, natural evolution of the quantum system. The notion of state actualization was later taken up by others, including Shimony, in the search for a law-like measurement process. Yet, the relation of quantum potentiality to Aristotle's original notion has been viewed as mainly terminological, even by those who used it thus. Here, I reconsider the relation of Heisenberg's notion to Aristotle's and show that it can be explicated in greater specificity than Heisenberg did. This is accomplished through the careful consideration of the role of potentia in physical causation and explanation, and done in order to provide a fuller understanding of this aspect of Heisenberg's approach to quantum mechanics. Most importantly, it is pointed out that Heisenberg's requirement of an external intervention during measurement that disrupts the otherwise independent, natural evolution of the quantum system is in accord with Aristotle's characterization of spontaneous causation. Thus, the need for a teleological understanding of the actualization of potentia, an often assumed requirement that has left this fundamental notion neglected, is seen to be spurious. This article is part of the themed issue `Second quantum revolution: foundational questions'.
RANGELAND SEQUESTRATION POTENTIAL ASSESSMENT
Energy Technology Data Exchange (ETDEWEB)
Lee Spangler; George F. Vance; Gerald E. Schuman; Justin D. Derner
2012-03-31
Rangelands occupy approximately half of the world's land area and store greater than 10% of the terrestrial biomass carbon and up to 30% of the global soil organic carbon. Although soil carbon sequestration rates are generally low on rangelands in comparison to croplands, increases in terrestrial carbon in rangelands resulting from management can account for significant carbon sequestration given the magnitude of this land resource. Despite the significance rangelands can play in carbon sequestration, our understanding remains limited. Researchers conducted a literature review to identify sustainably management practices that conserve existing rangeland carbon pools, as well as increase or restore carbon sequestration potentials for this type of ecosystem. The research team also reviewed the impact of grazing management on rangeland carbon dynamics, which are not well understood due to heterogeneity in grassland types. The literature review on the impact of grazing showed a wide variation of results, ranging from positive to negative to no response. On further review, the intensity of grazing appears to be a major factor in controlling rangeland soil organic carbon dynamics. In 2003, researchers conducted field sampling to assess the effect of several drought years during the period 1993-2002. Results suggested that drought can significantly impact rangeland soil organic carbon (SOC) levels, and therefore, carbon sequestration. Resampling was conducted in 2006; results again suggested that climatic conditions may have overridden management effects on SOC due to the ecological lag of the severe drought of 2002. Analysis of grazing practices during this research effort suggested that there are beneficial effects of light grazing compared to heavy grazing and non-grazing with respect to increased SOC and nitrogen contents. In general, carbon storage in rangelands also increases with increased precipitation, although researchers identified threshold levels of
Quantum potentiality revisited.
Jaeger, Gregg
2017-11-13
Heisenberg offered an interpretation of the quantum state which made use of a quantitative version of an earlier notion, [Formula: see text], of Aristotle by both referring to it using its Latin name, potentia , and identifying its qualitative aspect with [Formula: see text] The relationship between this use and Aristotle's notion was not made by Heisenberg in full detail, beyond noting their common character: that of signifying the system's objective capacity to be found later to possess a property in actuality. For such actualization, Heisenberg required measurement to have taken place, an interaction with external systems that disrupts the otherwise independent, natural evolution of the quantum system. The notion of state actualization was later taken up by others, including Shimony, in the search for a law-like measurement process. Yet, the relation of quantum potentiality to Aristotle's original notion has been viewed as mainly terminological, even by those who used it thus. Here, I reconsider the relation of Heisenberg's notion to Aristotle's and show that it can be explicated in greater specificity than Heisenberg did. This is accomplished through the careful consideration of the role of potentia in physical causation and explanation, and done in order to provide a fuller understanding of this aspect of Heisenberg's approach to quantum mechanics. Most importantly, it is pointed out that Heisenberg's requirement of an external intervention during measurement that disrupts the otherwise independent, natural evolution of the quantum system is in accord with Aristotle's characterization of spontaneous causation. Thus, the need for a teleological understanding of the actualization of potentia, an often assumed requirement that has left this fundamental notion neglected, is seen to be spurious.This article is part of the themed issue 'Second quantum revolution: foundational questions'. © 2017 The Author(s).
International Nuclear Information System (INIS)
Soezen, Adnan; Arcaklioglu, Erol
2005-01-01
Most of the locations in Turkey receive abundant solar-energy, because Turkey lies in a sunny belt between 36 deg. and 42 deg. N latitudes. Average annual temperature is 18 to 20 deg. C on the south coast, falls to 14-16 deg. C on the west coat, and fluctuates between 4 and 18 deg. C in the central parts. The yearly average solar-radiation is 3.6 kW h/m 2 day, and the total yearly radiation period is ∼2610 h. In this study, a new formulation based on meteorological and geographical data was developed to determine the solar-energy potential in Turkey using artificial neural-networks (ANNs). Scaled conjugate gradient (SCG), Pola-Ribiere conjugate gradient (CGP), and Levenberg-Marquardt (LM) learning algorithms and logistic sigmoid (logsig) transfer function were used in the networks. Meteorological data for last four years (2000-2003) from 12 cities (Canakkale, Kars, Hakkari, Sakarya, Erzurum, Zonguldak, Balikesir, Artvin, Corum, Konya, Siirt, and Tekirdag) spread over Turkey were used in order to train the neural-network. Meteorological and geographical data (latitude, longitude, altitude, month, mean sunshine-duration, and mean temperature) are used in the input layer of the network. Solar-radiation is in the output layer. The maximum mean absolute percentage error was found to be less than 3.832% and R 2 values to be about 99.9738% for the selected stations. The ANN models show greater accuracy for evaluating solar-resource possibilities in regions where a network of monitoring stations has not been established in Turkey. This study confirms the ability of the ANN to predict solar-radiation values accurately
Potentials of fissioning plasmas
International Nuclear Information System (INIS)
Karlheinz, Thom.
1979-01-01
Successful experiments with the nuclear pumping of lasers have demonstrated that in gaseous medium the kinetic energy of fission fragments can be converted directly into non-equilibrium optical radiation. This confirms the concept that the fissioning medium in a gas-phase nuclear reactor shows an internal structure such as a plasma in nearly thermal equilibrium varying up to a state of extreme-non-equilibrium. The accompanying variations of temperatures, pressure and radiative spectrum suggest wide ranges of applications. For example, in the gas-phase fission reactor concept enriched uranium hexafluoride or an uranium plasma replaces conventional fuel elements and permits operation above the melting point of solid materials. This potential has been motivation for the US National Aeronautics and Space Administration (NASA) to conduct relevant research for high specific impulse propulsion in space. The need to separate the high temperature gaseous fuel from the surfaces of a containing vessel and to protect them against thermal radiation has led to the concept of an externally moderated reactor in which the fissioning gaseous material is suspended by fluid dynamic means and the flow of opaque buffer gas removes the power. The gaseous nuclear fuel can slowly be circulated through the reactor for continuous on-site reprocessing including the annihilation of transuranium actinides at fission when being fed back into the reactor. An equilibrium of the generation and destruction of such actinides at fission when being fed back into the reactor. An equilibrium of the generation and destruction of such actinides can thus be achieved. These characteristics and the unique radiative properties led to the expectation that the gas-phase fission reactor could feature improved safety, safeguarding and economy, in addition to new technologies such as processing, photochemistry and the transmission of power over large distances in space
Patocka, Jiří; Gupta, Ramesh C; Wu, Qing-hua; Kuca, Kamil
2015-10-01
This review briefly describes the origin, chemistry, molecular mechanism of action, pharmacology, toxicology, and ecotoxicology of palytoxin and its analogues. Palytoxin and its analogues are produced by marine dinoflagellates. Palytoxin is also produced by Zoanthids (i.e. Palythoa), and Cyanobacteria (Trichodesmium). Palytoxin is a very large, non-proteinaceous molecule with a complex chemical structure having both lipophilic and hydrophilic moieties. Palytoxin is one of the most potent marine toxins with an LD50 of 150 ng/kg body weight in mice exposed intravenously. Pharmacological and electrophysiological studies have demonstrated that palytoxin acts as a hemolysin and alters the function of excitable cells through multiple mechanisms of action. Palytoxin selectively binds to Na(+)/K(+)-ATPase with a Kd of 20 pM and transforms the pump into a channel permeable to monovalent cations with a single-channel conductance of 10 pS. This mechanism of action could have multiple effects on cells. Evaluation of palytoxin toxicity using various animal models revealed that palytoxin is an extremely potent neurotoxin following an intravenous, intraperitoneal, intramuscular, subcutaneous or intratracheal route of exposure. Palytoxin also causes non-lethal, yet serious toxic effects following dermal or ocular exposure. Most incidents of palytoxin poisoning have manifested after oral intake of contaminated seafood. Poisonings in humans have also been noted after inhalation, cutaneous/systemic exposures with direct contact of aerosolized seawater during Ostreopsis blooms and/or through maintaining aquaria containing Cnidarian zoanthids. Palytoxin has a strong potential for toxicity in humans and animals, and currently this toxin is of great concern worldwide.
On the scalar potential models from the isospectral potential class
Energy Technology Data Exchange (ETDEWEB)
Lima, V. Gomes [Universidade Federal Rural do Rio de Janeiro, Seropedica, RJ (Brazil). Dept. de Fisica; Santos, V. Silva [Paraiba Univ., Campina Grande, PB (Brazil). Dept. de Engenharia Civil; Rodrigues, R. de Lima [Centro Brasileiro de Pesquisas Fisicas (CBPF), Rio de Janeiro, RJ (Brazil)]. E-mail: rafaelr@cbpf.br
2001-10-01
The static field classical configuration in (1+1)-dimensions for new non-linear potential models is investigated from an isospectral potential class and the concept of bosonic zero mode solution. One of the models considered here has a static nontopological configuration with a single vacuum state, whose potential in the stability equation corresponds to broken a supersymmetry. (author)
Folding models for elastic and inelastic scattering
International Nuclear Information System (INIS)
Satchler, G.R.
1982-01-01
The most widely used models are the optical model potential (OMP) for elastic scattering, and its generalization to non-spherical shapes, the deformed optical model potential (DOMP) for inelastic scattering. These models are simple and phenomenological; their parameters are adjusted so as to reproduce empirical data. Nonetheless, there are certain, not always well-defined, constraints to be imposed. The potential shapes and their parameter values must be reasonable and should vary in a smooth and systematic way with the masses of the colliding nuclei and their energy. One way of satisfying these constraints, without going back to a much more fundamental theory, is through the use of folding models. The basic justification for using potentials of the Woods-Saxon shape for nucleon-nucleus scattering, for example, is our knowledge that a nuclear density distribution is more-or-less constant in the nuclear interior with a diffuse surface. When this is folded with a short-range nucleon-nucleon interaction, the result is a similar shape with a more diffuse surface. Folding procedures allow us to incorporate many aspects of nuclear structure (although the nuclear size is one of the most important), as well as theoretical ideas about the effective interaction of two nucleons within nuclear matter. It also provides us with a means of linking information obtained from nuclear (hadronic) interactions with that from other sources, as well as correlating that from the use of different hadronic probes. Folding model potentials, single-folded potentials, and the double-folding model including applications to heavy-ion scattering are discussed
Elastic scattering of 12C by 28Si
International Nuclear Information System (INIS)
Cheng, C.M.; Maher, J.V.; Chiou, M.S.; Jordan, W.J.; Peng, J.C.; Oelert, W.; Gunn, G.D.; Snyder, F.D.
1979-01-01
12 C + 28 Si elastic scattering angular distributions have been measured at twenty-three bombarding energies over a range 19 MeV 0 in the bombarding energy range 30--40 MeV. No optical potential has been found to give a good account of all the data; the best potential is a surface transparent Woods-Saxon potential which has energy dependences for both real and imaginary well depths. Examination of potentials which give reasonably good fits to the 36 MeV data shows that, although these potentials agree on a real well depth at a reasonable ''strong absorption radius,'' they can have quite different Argand diagrams: even in the range of the most sensitive partial waves. A Regge analysis finds several equally good families of Regge parameters for the same choice of background potential, but larger angle data might allow this ambiguity to be lifted. A Breit-Wigner analysis gives results which are at least partially consistent with the resonance parameters reported by Ost et al. Coupled-channel calculations with a 20% reduction of real and imaginary optical model well depths give a good account of inelastic scattering to the 28 Si 2 + state while leaving the elastic scattering essentially unchanged from the predictions of the unmodified one-channel optical model. In the energy range of this study the grazing partial wave is found to be the same as the most important exit channel partial wave of the 24 Mg( 16 O, 12 C) 28 Si ground state transition
PV potential and potential PV rent in European regions
DEFF Research Database (Denmark)
Hansen, Anders Chr.; Thorn, Paul
2013-01-01
The paper provides a GIS based model for assessing the potentials of photovoltaic electricity in Europe by NUTS 2 regions. The location specific energy potential per PV-‐panel area is estimated based on observations of solar irradiation, conversion efficiency, levelised costs and the social value...... of PV-‐electricity. Combined with the potential density of PV-‐panel area based on land cover and environental restrictions, the PV energy potential and the potential PV ressource rent is calculated. These calculations enbable the model to estimate the regional patterns at NUTS 2 level...
An improved potential for krypton
International Nuclear Information System (INIS)
Aziz, R.A.
1979-01-01
An improved potential for krypton is presented. It has the simple but realistic form used by Aziz and Chen for argon based on the HFD potential suggested by Ahlrichs et.al. The potential, with known long-range behaviour, was fitted to second virial, viscosity and thermal conductivity data. The potential appears to have the best overall predictive ability for dilute gas, bulk and microscopic data. (author)
Instantons and the interquark potential
International Nuclear Information System (INIS)
McDougall, N.A.
1980-01-01
It is argued that the contributions to the interquark potential from instantons of all scale sizes may be calculated in a consistent, cut-off-independent manner using the dilute-gas approximation; and that an interquark potential dominated at intermediate distances by these contributions is similar to already successful phenomenological potentials. (orig.)
Potentials of surfaces in space
International Nuclear Information System (INIS)
Whipple, E.C.
1981-01-01
The potential of a body in space is determined by a balance between various charging currents such as the transfer of charge from plasma particles, photoemission, and secondary electron emission. These processes are evaluated for bodies in the solar system and in interstellar space under the headings; an overview of charging, survey of early work on charging, charging processes, effects of non-isotropic plasmas and magnetic and electric fields, calculation of surface potentials, differential charging, potential barriers and discharge processes, measurements of potential, potential modification and control on spacecraft, and astrophysical applications. (U.K.)
Measurement of proton autoneutralization potential
International Nuclear Information System (INIS)
Garcia, M.
1984-09-01
A proton space charge having multi-MeV kinetic energy was injected through a thin ground plane to extract electrons and produce a time-dependent autoneutralization space potential. An electon-emitting floating-potential resistive divider was used to measure the space potential during 20 ns of the proton current pulse. During this time, proton kinetic energy fell from 10.6 MeV to 8.5 MeV and thus the space potential (taken as 1.09 x the floating potential) fell from 5.8 kV to 4.6 kV
Pair potentials in liquid metals
International Nuclear Information System (INIS)
Faber, T.E.
1980-01-01
The argument which justifies the use of a pair potential to describe the structure-dependent term in the energy of liquid metals is briefly reviewed. Because there is an additional term in the energy which depends upon volume rather than structure, and because the pair potential itself is volume-dependent, the relationship between pair potential and observable properties such as pressure, bulk modulus and pair distribution function is more complicated for liquid metals than it is for molecular liquids. Perhaps for this reason, the agreement between pair potentials inferred from observable properties and pair potentials calculated by means of pseudo-potential theory is still far from complete. The pair potential concept is applicable only to simple liquid metals, in which the electron-ion interaction is weak. No attempt is made to discuss liquid transition and rare-earth metals, which are not simple in this sense. (author)
State-dependent classical potentials
International Nuclear Information System (INIS)
D'Amico, M.
2001-01-01
As alternative treatment to the potential operators of standard quantum mechanics is presented. The method is derived from Bohm's mechanics. The operator scalar (V) and vector (A) potential functions are replaced by a quantum potential. It is argued that the classical potential is a special limiting case of a more general quantum potential. The theory is illustrated by deriving an equivalent single-particle equation for the i-th particle of an n-body Bohmian system. The resulting effective state-dependent potential holds the interaction between the single-particle self-wave ψ s and the environment wave ψ e of the n - 1 remaining particles. The effective state-dependent potential is offered as a resolution to the Aharonov-Bohm effect where the phase difference is shown to result from the presence of ψ e . Finally, the interaction between ψ s and ψ e is illustrated graphically
Fast-neutron elastic scattering from elemental vanadium
International Nuclear Information System (INIS)
Smith, A.B.; Guenther, P.T.; Lawson, R.D.
1988-03-01
Differential neutron elastic- and inelastic-scattering cross sections of vanadium were measured from 4.5 to 10 MeV. These results were combined with previous 1.5 to 4.0 MeV data from this laboratory, the 11.1 MeV elastic-scattering results obtained at Ohio University, and the reported neutron total cross sections to energies of ∼20.0 MeV, to form a data base which was interpreted in terms of the spherical optical-statistical model. A fit to the data was achieved by making both the strengths and geometries of the optical-model potential energy dependent. This energy dependence was large below ∼6.0 MeV. Above ∼6.0 MeV the energy dependencies are smaller, and similar to those characteristic of global models. Using the dispersion relationship and the method of moments, the optical-model potential energy deduced from 0.0 to 11.1 MeV neutron-scattering data was extrapolated to higher energies and to the bound-state regime. This extrapolation leads to predicted neutron total cross sections that are within 3% of the experimental values throughout the energy range 0.0 to 20.0 MeV. Furthermore, the values of the volume-integral-per-nucleon of the real potential are in excellent agreement with those needed to reproduce the observed binding energies of particle- and hole-states. The latter gives clear evidence of the Fermi surface anomaly. Using only the 0.0 to 11.1 MeV data, the predicted E < O behavior of the strength and radius of the real shell-model Woods-Saxon potential are somewhat different from those obtained by Mahaux and Sartor in their analysis of nuclei near closed shells. 61 refs., 9 figs., 2 tabs
International Nuclear Information System (INIS)
Roberts, M.L.; Felsher, P.D.; Weisel, G.J.; Chen, Z.; Howell, C.R.; Tornow, W.; Walter, R.L.; Horen, D.J.
1991-01-01
High-accuracy measurements of A y (θ) data for elastic scattering and inelastic scattering to the first excited state for n+ 208 Pb have been performed at 6, 7, 8, 9, and 10 MeV. In addition, σ(θ) was measured at 8 MeV. These data provide an important subset for the growing database for the n+ 208 Pb system from bound-state energies to energies above 40 MeV, the limit of the range of interest here. This database has been interpreted via several approaches. First, a conventional Woods-Saxon spherical optical was used to obtain three potential representations for the energy range from 4 to 40 MeV: ''best fits'' at each energy, constant-geometry global fit with linear energy dependences for the potential strengths for the range 4.0--40 MeV, and an extension of the latter model to allow a linear energy dependence on the radii and diffuseness. A preference for a complex spin-orbit interaction was observed in all cases. Second, the dispersion relation was introduced into the spherical optical model to obtain a more ''realistic'' representation. In our approach, the strength and shape of the real potential was modified by calculating the dispersion-relation contributions that originate from the presence of the surface and volume imaginary terms. Two potentials were developed, one based only on the scattering data (from 4.0 to 40 MeV) and another based additionally on single-particle and single-hole information down to a binding energy of 17 MeV. In addition, the σ(θ) and A y (θ) measurements were compared to earlier conventional and dispersion-relation models. One of the latter of these included an l dependence in the absorptive surface term, and we applied this model in the 6- to 10-MeV region to describe all the σ(θ) and the new A y (θ)
The neutron optical model potential
International Nuclear Information System (INIS)
Hodgson, P.E.
1989-01-01
The present status of optical model calculations of neutron scattering and interactions is reviewed, with special emphasis on more recent developments and the more promising lines of research. The use of dispersion relations to provide an extra constraint on the potential is discussed, together with their application to studies of the Fermi surface anomaly. The application of potential inversion techniques to determine the form of the potential is also considered. (author). 39 refs, figs
Oxygen potentials of transuranium oxides
International Nuclear Information System (INIS)
Haruyoshi Otobe; Mituso Akabori; Arai Yasuo; Kazuo Minato
2008-01-01
The oxygen potentials of pyrochlore-type Pu 2 Zr 2 O 7+y , fluorite-type (Pu 0.5 Zr 0.5 )O 2-x and AmO 2-x have been measured by the electromotive force (EMF) method with a zirconia solid-electrolyte. The oxygen potentials of these oxides were reviewed. The phase relations, microstructure, equilibrium state of these oxides were discussed, referring to the isothermal curve of the oxygen potentials. (authors)
Shell structure and orbit bifurcations in finite fermion systems
Magner, A. G.; Yatsyshyn, I. S.; Arita, K.; Brack, M.
2011-10-01
We first give an overview of the shell-correction method which was developed by V.M. Strutinsky as a practicable and efficient approximation to the general self-consistent theory of finite fermion systems suggested by A.B. Migdal and collaborators. Then we present in more detail a semiclassical theory of shell effects, also developed by Strutinsky following original ideas of M.C. Gutzwiller. We emphasize, in particular, the influence of orbit bifurcations on shell structure. We first give a short overview of semiclassical trace formulae, which connect the shell oscillations of a quantum system with a sum over periodic orbits of the corresponding classical system, in what is usually called the "periodic orbit theory". We then present a case study in which the gross features of a typical double-humped nuclear fission barrier, including the effects of mass asymmetry, can be obtained in terms of the shortest periodic orbits of a cavity model with realistic deformations relevant for nuclear fission. Next we investigate shell structures in a spheroidal cavity model which is integrable and allows for far-going analytical computation. We show, in particular, how period-doubling bifurcations are closely connected to the existence of the so-called "superdeformed" energy minimum which corresponds to the fission isomer of actinide nuclei. Finally, we present a general class of radial power-law potentials which approximate well the shape of a Woods-Saxon potential in the bound region, give analytical trace formulae for it and discuss various limits (including the harmonic oscillator and the spherical box potentials).
International Nuclear Information System (INIS)
Lind, P.
1993-02-01
The completeness properties of the discrete set of bound state, virtual states and resonances characterizing the system of a single nonrelativistic particle moving in a central cutoff potential is investigated. From a completeness relation in terms of these discrete states and complex scattering states one can derive several Resonant State Expansions (RSE). It is interesting to obtain purely discrete expansion which, if valid, would significantly simplify the treatment of the continuum. Such expansions can be derived using Mittag-Leffler (ML) theory for a cutoff potential and it would be nice to see if one can obtain the same expansions starting from an eigenfunction theory that is not restricted to a finite sphere. The RSE of Greens functions is especially important, e.g. in the continuum RPA (CRPA) method of treating giant resonances in nuclear physics. The convergence of RSE is studied in simple cases using square well wavefunctions in order to achieve high numerical accuracy. Several expansions can be derived from each other by using the theory of analytic functions and one can the see how to obtain a natural discretization of the continuum. Since the resonance wavefunctions are oscillating with an exponentially increasing amplitude, and therefore have to be interpreted through some regularization procedure, every statement made about quantities involving such states is checked by numerical calculations.Realistic nuclear wavefunctions, generated by a Wood-Saxon potential, are used to test also the usefulness of RSE in a realistic nuclear calculation. There are some fundamental differences between different symmetries of the integral contour that defines the continuum in RSE. One kind of symmetry is necessary to have an expansion of the unity operator that is idempotent. Another symmetry must be used if we want purely discrete expansions. These are found to be of the same form as given by ML. (29 refs.)
Ambipolar potential formation in TMX
International Nuclear Information System (INIS)
Correl, D.L.; Allen, S.L.; Casper, T.A.
1981-01-01
TMX experimental data on ambipolar potential control and on the accompanying electrostatic confinement are reported. New results on the radial dependence of the central-cell confining potential are given. Radial and axial particle losses as well as scaling of the central-cell axial confinement are discussed
The erosive potential of lollipops
Brand, H.S.; Gambon, D.L.; Paap, A.; Bulthuis, M.S.; Veerman, E.C.I.; Nieuw Amerongen, A.V.
2009-01-01
Aim: To determine the erosive potential of several commercially available lollipops and the protective effect of saliva. Methods: The erosive potential of lollipops was determined in vitro by measuring the pH and neutralisable acidity. Subsequently, 10 healthy volunteers tested different types of
Miscellaneous conditions and future potential
International Nuclear Information System (INIS)
Berquist, T.H.; Ehman, R.L.; Richardson, M.L.; Helms, C.A.
1987-01-01
The previous chapters have discussed basic principles and the types of musculoskeletal pathology that have been most extensively studied with magnetic resonance (MR) techniques. MR has also demonstrated significant potential in other areas, but experience is more limited. Despite this limited experience, the potential application of MR imaging in these areas is discussed in this paper
Potential photosynthesis of crop surfaces.
Wit, de C.T.
1959-01-01
A formula for calculating the potential photosynthesis of a closed crop surface is proposed, assuming that the leaves of the crop are not arranged in any definite direction. In the Netherlands, values for potential photosynthesis vary from 290 kg. CH2O/ha./day in June to 50 kg./ha./day in December.
Supermodular Games and Potential Games
Brânzei, R.; Mallozzi, L.; Tijs, S.H.
2001-01-01
Potential games and supermodular games are attractive games, especially because under certain conditions they possess pure Nash equilibria. Subclasses of games with a potential are considered which are also strategically equivalent to supermodular games. The focus is on two-person zero-sum games and
Finite-Temperature Higgs Potentials
International Nuclear Information System (INIS)
Dolgopolov, M.V.; Gurskaya, A.V.; Rykova, E.N.
2016-01-01
In the present article we consider the short description of the “Finite-Temperature Higgs Potentials” program for calculating loop integrals at vanishing external momenta and applications for extended Higgs potentials reconstructions. Here we collect the analytic forms of the relevant loop integrals for our work in reconstruction of the effective Higgs potential parameters in extended models (MSSM, NMSSM and etc.)
International Nuclear Information System (INIS)
Igamov, S.B.; Yarmukhamedov, R.
2007-01-01
Full text: The 7 Be(p,γ) 8 B reaction rate given by in terms of the zero-energy astrophysical S-factor S(0) is one of the main input data in the solar neutrino problem because the high energy neutrinos are produced via the decay 8 B→ 7 Be+e + + n e . This quantity is determined by both extrapolating the measured absolute cross sections σexp (E) (or equivalently its experimental S-factors S exp (E) ) to solar energies (≅ 25 keV) and the theoretical predictions. Despite the steady and impressive progress in our understanding of this reaction have been made in last years in measurements S exp (E) at extremely low energies and the theoretical predictions S(E) at solar energies (E≤25 keV), ambiguities (up to about 35%) associated with prediction for S(0) however still exist, and it may considerably influence the predictions of the standard solar model. In this work the modified two - body potential approach is applied for a new analysis of the highly precise experimental astrophysical S-factors for the direct capture 7 Be(p, γ) 8 B reaction at E≤400 keV and 1000≤E≤1200 keV to obtain 'indirectly measured' values both of the asymptotic normalization coefficient (ANC) for the p+ 7 Be→ 8 B and of S(E) at E≤115 keV, including E=0. In this approach S(E) is expressed in the terms of ANC C Aα;lj 2 but not in the terms of the usual spectroscopic factor Z Aα;lj , which is related to the ANC C Aα;l. j as Z aα;lj =C Aα;lj 2 /b lj 2 , where b lj is the single-particle ANC for the wave function of the bound 8 B( 7 Be+p) state calculated within the shell model using the phenomenological Woods-Saxon potential with the geometric parameters (a radius r o and a diffuseness a). The approach allows one to remove the model dependence of the calculated direct on S(E) on the geometric parameters r o and a both for the two-body bound ( 7 Be+p) state and the p 7 Be- scattering state in minimum. The analysis of the experimental S exp (E) is performed by verifying values of
Fusion and quasifission studies for the 40Ca+186W,192Os reactions
Prasad, E.; Hinde, D. J.; Williams, E.; Dasgupta, M.; Carter, I. P.; Cook, K. J.; Jeung, D. Y.; Luong, D. H.; Palshetkar, C. S.; Rafferty, D. C.; Ramachandran, K.; Simenel, C.; Wakhle, A.
2017-09-01
Background: All elements above atomic number 113 have been synthesized using hot fusion reactions with calcium beams on statically deformed actinide target nuclei. Quasifission and fusion-fission are the two major mechanisms responsible for the very low production cross sections of superheavy elements. Purpose: To achieve a quantitative measurement of capture and quasifission characteristics as a function of beam energy in reactions forming heavy compound systems using calcium beams as projectiles. Methods: Fission fragment mass-angle distributions were measured for the two reactions 40Ca+186W and 40C+192Os, populating 226Pu and 232Cm compound nuclei, respectively, using the Heavy Ion Accelerator Facility and CUBE spectrometer at the Australian National University. Mass ratio distributions, angular distributions, and total fission cross sections were obtained from the experimental data. Simulations to match the features of the experimental mass-angle distributions were performed using a classical phenomenological approach. Results: Both 40Ca+186W and 40C+192Os reactions show strong mass-angle correlations at all energies measured. A maximum fusion probability of 60 -70 % is estimated for the two reactions in the energy range of the present study. Coupled-channels calculations assuming standard Woods-Saxon potential parameters overpredict the capture cross sections. Large nuclear potential diffuseness parameters ˜1.5 fm are required to fit the total capture cross sections. The presence of a weak mass-asymmetric quasifission component attributed to the higher angular momentum events can be reproduced with a shorter average sticking time but longer mass-equilibration time constant. Conclusions: The deduced above-barrier capture cross sections suggest that the dissipative processes are already occurring outside the capture barrier. The mass-angle correlations indicate that a compact shape is not achieved for deformation aligned collisions with lower capture barriers
International Nuclear Information System (INIS)
Becchetti, F.D.; Harvey, B.G.; Kovar, D.; Mahoney, J.; Maguire, C.; Scott, D.K.
1975-01-01
The neutron levels in 209 Pb have been studied with the 208 Pb( 16 O, 15 O) reaction at a bomdarding energy of 139 MeV. Spectroscopic factors (S) have been deduced using a finite-range distorted-wave Born approximation (DWBA) with recoil. The 2g 9 / 2 , 1i 11 / 2 , 2g 7 / 2 , and 3d 3 / 2 levels are found to have S approximately-greater-than 0.9 while S approx. = 0.7 for the 1j 15 / 2 level at 1.4 MeV excitation. Evidence is found for other 1j 15 / 2 fragments being at 3.05 MeV and approx. 3.8 MeV with S approx. = 0.08 and 0.26, respectively, which would place the centroid of the 1j 15 / 2 level at E/subx/ approx. = 2.2 MeV. DWBA predicts a shift in the maxima of the angular distributions as a function of Q value which is not observed experimentally. A comparison with the proton transfer reaction 208 Pb( 16 O, 15 N) 209 Bi has been used to deduce the geometrical parameters of a neutron shell model potential appropriate for nuclei with A approximately-greater-than 200. The parameters of this Wood-Saxon potential are: V/subR/=-50.5 MeV,r/subR/=1.19 fm, a/subR/=0.75 fm, V)=-5.5 MeV, r)=1.01 fm, and a)=0.75 fm
Ha, Eunja; Cheoun, Myung-Ki
2015-02-01
The deformed proton-neutron quasiparticle random phase approximation (QRPA) has been developed and applied to evaluate Gamow-Teller (GT) transition strength distributions, including high-lying excited states. The data of high-lying excited states are recently available beyond one or two nucleon threshold by charge exchange reactions using hundreds of MeV projectiles. Our calculations started with single-particle states calculated using a deformed, axially symmetric Woods-Saxon potential. The neutron-neutron and proton-proton pairing correlations are explicitly taken into account at the deformed Bardeen-Cooper-Schriffer theory. Additionally, the ground state correlations and two-particle and two-hole mixing states were included in the deformed QRPA. In this work, we used a realistic two-body interaction, given by the Brueckner G-matrix based on the CD Bonn potential to reduce the ambiguity on the nucleon-nucleon interactions inside nuclei. We applied our formalism to the GT transition strengths for 76Ge, 76,82Se, and 90,92Zr, and compared the results with the available experimental data. The GT strength distributions were sensitive to the deformation parameter as well as its sign, i.e., oblate or prolate. The Ikeda sum rule, which is usually thought to be satisfied under the one-body current approximation, regardless of nucleon models, was used to test our numerical calculations and shown to be satisfied without introducing the quenching factor, if high-lying GT excited states were properly taken into account. Most of the GT strength distributions of the nuclei considered in this work have the high-lying GT excited states beyond one-nucleon threshold, which are shown to be consistent with the available experimental data.
High-temperature axion potential
International Nuclear Information System (INIS)
Dowrick, N.J.; McDougall, N.A.
1989-01-01
We investigate the possibility of new terms in the high-temperature axion potential arising from the dynamical nature of the axion field and from higher-order corrections to the θ dependence in the free energy of the quark-gluon plasma. We find that the dynamical nature of the axion field does not affect the potential but that the higher-order effects lead to new terms in the potential which are larger than the term previously considered. However, neither the magnitude nor the sign of the potential can be calculated by a perturbative expansion of the free energy since the coupling is too large. We show that a change in the magnitude of the potential does not significantly affect the bound on the axion decay constant but that the sign of the potential is of crucial importance. By investigating the formal properties of the functional integral within the instanton dilute-gas approximation, we find that the sign of the potential does not change and that the minimum remains at θ=0. We conclude that the standard calculation of the axion energy today is not significantly modified by this investigation
Cold atoms in singular potentials
International Nuclear Information System (INIS)
Denschlag, J. P.
1998-09-01
We studied both theoretically and experimentally the interaction between cold Li atoms from a magnetic-optical trap (MOT) and a charged or current-carrying wire. With this system, we were able to realize 1/r 2 and 1/r potentials in two dimensions and to observe the motion of cold atoms in both potentials. For an atom in an attractive 1/r 2 potential, there exist no stable trajectories, instead there is a characteristic class of trajectories for which atoms fall into the singularity. We were able to observe this falling of atoms into the center of the potential. Moreover, by probing the singular 1/r 2 potential with atomic clouds of varying size and temperature we extracted scaling properties of the atom-wire interaction. For very cold atoms, and very thin wires the motion of the atoms must be treated quantum mechanically. Here we predict that the absorption cross section for the 1/r 2 potential should exhibit quantum steps. These quantum steps are a manifestation of the quantum mechanical decomposition of plane waves into partial waves. For the second part of this work, we realized a two dimensional 1/r potential for cold atoms. If the potential is attractive, the atoms can be bound and follow Kepler-like orbits around the wire. The motion in the third dimension along the wire is free. We were able to exploit this property and constructed a novel cold atom guide, the 'Kepler guide'. We also demonstrated another type of atom guide (the 'side guide'), by combining the magnetic field of the wire with a homogeneous offset magnetic field. In this case, the atoms are held in a potential 'tube' on the side of the wire. The versatility, simplicity, and scaling properties of this guide make it an interesting technique. (author)
Exceptional circles of radial potentials
International Nuclear Information System (INIS)
Music, M; Perry, P; Siltanen, S
2013-01-01
A nonlinear scattering transform is studied for the two-dimensional Schrödinger equation at zero energy with a radial potential. Explicit examples are presented, both theoretically and computationally, of potentials with nontrivial singularities in the scattering transform. The singularities arise from non-uniqueness of the complex geometric optics solutions that define the scattering transform. The values of the complex spectral parameter at which the singularities appear are called exceptional points. The singularity formation is closely related to the fact that potentials of conductivity type are ‘critical’ in the sense of Murata. (paper)
Potential Theory Surveys and Problems
Lukeš, Jaroslav; Netuka, Ivan; Veselý, Jiří
1988-01-01
The volume comprises eleven survey papers based on survey lectures delivered at the Conference in Prague in July 1987, which covered various facets of potential theory, including its applications in other areas. The survey papers deal with both classical and abstract potential theory and its relations to partial differential equations, stochastic processes and other branches such as numerical analysis and topology. A collection of problems from potential theory, compiled on the occasion of the conference, is included, with additional commentaries, in the second part of this volume.
Chemical potentials in gauge theories
International Nuclear Information System (INIS)
Actor, A.; Pennsylvania State Univ., Fogelsville
1985-01-01
One-loop calculations of the thermodynamic potential Ω are presented for temperature gauge and non-gauge theories. Prototypical formulae are derived which give Ω as a function of both (i) boson and/or fermion chemical potential, and in the case of gauge theories (ii) the thermal vacuum parameter Asub(O)=const (Asub(μ) is the euclidean gauge potential). From these basic abelian gauge theory formulae, the one-loop contribution to Ω can readily be constructed for Yang-Mills theories, and also for non-gauge theories. (orig.)
International Nuclear Information System (INIS)
Green, A.M.
1978-01-01
The first part of this talk is based on the one presented at the Tokyo conference last September and can be found in ref( 1 ). This coveres such topics as the Paris and Stonybrook potentials, the new values of the NN coupling constants and also our understanding of the NNω coupling constant. The second part reviews recent developments concerning the Paris potential, the application of the MIT bag model to the NN interaction, the effect of crossed pion processes and vertex form factors. Comments made about the possible future trends of NN potential calculations. The current status of the D-state probability of the deuteron is discussed. (orig./AH) [de
Potential Theory of Multicomponent Adsorption
DEFF Research Database (Denmark)
Shapiro, Alexander; Stenby, Erling Halfdan
1998-01-01
We developed a theory of multicomponent adsorption on the basis of the potential concept originally suggested by Polanyi. The mixture is considered as a heterogeneous substance segregated in the external field emitted by the adsorbent. The same standard equation of state, with no additional fitting...... and high degree of predictability of the theory developed....... the potential theory and the spreading pressure concept is established, and problems of the theory consistency are studied. Numerical algorithms are suggested for evaluation of the segregated state of the mixture in the potential field of adsorption forces. Comparison with experimental data shows good agreement...
The deuteron microscopic optical potential
International Nuclear Information System (INIS)
Lu Congshan; Zhang Jingshang; Shen Qingbiao
1991-01-01
The two particle Green's function is introduced. When the direct interaction between two nucleons is neglected, the first and second order mass operators of two particles are the sum of those for each particle. The nucleon microscopic optical potential is calculated by applying nuclear matter approximation and effective Skyrme interaction. Then the deuteron microscopic optical potential (DMOP) is calculated by using fold formula. For improvement of the theory, the two particle polarization diagram contribution to the imaginary part of the deuteron microscopic optical potential is studied
Quark potential of spontaneous strings
International Nuclear Information System (INIS)
German, G.; Kleinert, H.
1989-01-01
The authors present some recent developments in string models with an extrinsic curvature term in action. Particular emphasis is placed upon the static quark potential and on the thermal deconfinement properties of spontaneous strings
Singular potentials in quantum mechanics
International Nuclear Information System (INIS)
Aguilera-Navarro, V.C.; Koo, E. Ley
1995-10-01
This paper is a review of some mathematical methods as recently developed and applied to deal with singular potentials in Quantum Mechanics. Regular and singular perturbative methods as well as variational treatments are considered. (author). 25 refs
Potential Leaders and Democratic Values
Monsma, Stephen V.
1971-01-01
Indicates that potential contenders for public office are likely to be more knowledgeable, interested, and libertarian than the average citizen. Concludes that these differences exist before leaders are elected and that this discrimination is functional in a democracy. (MB)
Molecular potentials and relaxation dynamics
International Nuclear Information System (INIS)
Karo, A.M.
1981-01-01
The use of empirical pseudopotentials, in evaluating interatomic potentials, provides an inexpensive and convenient method for obtaining highly accurate potential curves and permits the modeling of core-valence correlation, and the inclusion of relativistic effects when these are significant. As an example, recent calculations of the chi 1 Σ + and a 3 Σ + states of LiH, NaH, KH, RbH, and CsH and the chi 2 Σ + states of their anions are discussed. Pseudopotentials, including core polarization terms, have been used to replace the core electrons, and this has been coupled with the development of compact, highly-optimized basis sets for the corresponding one- and two-electron atoms. Comparisons of the neutral potential curves with experiment and other ab initio calculations show good agreement (within 1000 cm -1 over most of the potential curves) with the difference curves being considerably more accurate
ANTAGONISTIC POTENTIAL OF FLUORESCENT Pseudomonas ...
African Journals Online (AJOL)
Prof. Adipala Ekwamu
GROWTH OF TOMATO CHALLENGED WITH PHTOPATHOGENS ... This study focused on the antagonistic potential of fluorescent Pseudomonas in vitro, and its inoculation effect on growth .... the 5 days old culture in starch agar with Lugol's.
Potential measurements in tandem mirrors
International Nuclear Information System (INIS)
Glowienka, J.C.
1985-11-01
The US mirror program has begun conducting experiments with a thermal barrier tandem mirror configuration. This configuration requires a specific axial potential profile and implies measurements of potential for documentation and optimization of the configuration. This report briefly outlines the motivation for the thermal barrier tandem mirror and then outlines the techniques used to document the potential profile in conventional and thermal barrier tandem mirrors. Examples of typical data sets from the world's major tandem mirror experiments, TMX and TMX-U at Lawrence Livermore National Laboratory (LLNL) and Gamma 10 at Tsukuba University in Japan, and the current interpretation of the data are discussed together with plans for the future improvement of measurements of plasma potential
Towards a commercially potential process
DEFF Research Database (Denmark)
Panpipat, Worawan; Xu, Xuebing; Guo, Zheng
2012-01-01
In order to examine the industrial potential to indirectly isolate phytosterols from deodoriser distillates (DODs), enzymatic transesterification of an industrial rapeseed and soybean oil DOD mixture with bioethanol was investigated using commercial lipases and a few newly immobilised preparations...
Effective potentials for twisted fields
International Nuclear Information System (INIS)
Banach, R.
1981-01-01
Minus the density of the effective action, evaluated at the lowest eigenfunction of the (space-time) derivative part of the second (functional) derivative of the classical action, is proposed as a generalised definition of the effective potential, applicable to twisted as well as untwisted sectors of a field theory. The proposal is corroborated by several specific calculations in the twisted sector, namely phi 4 theory (real and complex) and wrong-sign-Gordon theory, in an Einstein cylinder, where the exact integrability of the static solutions confirms the effective potential predictions. Both models exhibit a phase transition, which the effective potential locates, and the one-loop quantum shift in the critical radius is computed for the real phi 4 model, being a universal result. Topological mass generation at the classical level is pointed out, and the exactness of the classical effective potential approximation for complex phi 4 is discussed. (author)
Perihelium shifts in central potentials
International Nuclear Information System (INIS)
Amorim, A.E.A.; Ferreira, P.L.
1987-01-01
Motivated by the rigorous results on level ordering for arbitrary central potentials recently derived in the literature a classical treatment of the perihelium shifts is presented, based on the consideration of those orbits which lie in the vicinity of a circular orbit. The role played by the Laplacian of the potential is emphasized. By the same approach Bertrand's theorem is also discussed, in connection with Arnold's proof. (Author) [pt
Static quark-antiquark potential
International Nuclear Information System (INIS)
Deo, B.B.; Barik, B.K.
1983-01-01
A heavy-quark--antiquark potential is suggested which connects asymptotic freedom and quark confinement in a unified manner by formal methods of field theory using some plausible assumptions. The potential has only one additional adjustable parameter B which is proportional to (M/sub q//m/sub q/), where M/sub q/ and m/sub q/ are the constituent and current quark masses, respectively
Molecular potentials and relaxation dynamics
International Nuclear Information System (INIS)
Karo, A.M.
1981-01-01
The use of empirical pseudopotentials, in evaluating interatomic potentials, provides an inexpensive and convenient method for obtaining highly accurate potential curves and permits the modeling of core-valence correlation, and the inclusion of relativistic effects when these are significant. Recent calculations of the X 1 Σ + and a 3 Σ + states of LiH, NaH, KH, RbH, and CsH and the X 2 Σ + states of their anions are discussed. Pseudopotentials, including core polarization terms, have been used to replace the core electrons, and this has been coupled with the development of compact, higly-optimized basis sets for the corresponding one- and two-electron atoms. Comparisons of the neutral potential curves with experiment and other ab initio calculations show good agreement (within 1000 cm -1 over most of the potential curves) with the difference curves being considerably more accurate. In the method of computer molecular dynamics, the force acting on each particle is the resultant of all interactions with other atoms in the neighborhood and is obtained as the derivative of an effective many-body potential. Exploiting the pseudopotential approach, in obtaining the appropriate potentials may be very fruitful in the future. In the molecular dynamics example considered here, the conventional sum-of-pairwise-interatomic-potentials (SPP) approximation is used with the potentials derived either from experimental spectroscopic data or from Hartree-Fock calculations. The problem is the collisional de-excitation of vibrationally excited molecular hydrogen at an Fe surface. The calculations have been carried out for an initial vibrotational state v = 8, J = 1 and a translational temperature corresponding to a gas temperature of 500 0 K. Different angles of approach and different initial random impact points on the surface have been selected. For any given collision with the wall, the molecule may pick up or lose vibrotatonal and translational energy
Deuteron microscopic optical model potential
International Nuclear Information System (INIS)
Guo Hairui; Han Yinlu; Shen Qingbiao; Xu Yongli
2010-01-01
A deuteron microscopic optical model potential is obtained by the Green function method through nuclear-matter approximation and local-density approximation based on the effective Skyrme interaction. The microscopic optical model potential is used to calculate the deuteron reaction cross sections and the elastic scattering angular distributions for some target nuclei in the mass range 6≤A≤208 with incident deuteron energies up to 200 MeV. The calculated results are compared with the experimental data.
Potential scattering of Dirac particles
International Nuclear Information System (INIS)
Thaller, B.
1981-01-01
A quantum mechanical interpretation of the Dirac equation for particles in external electromagnetic potentials is discussed. It is shown that a consequent development of the Stueckelberg-Feynman theory into a probabilistic interpretation of the Dirac equation corrects some prejudices concerning negative energy states, Zitterbewegung and bound states in repulsive potentials and yields the connection between propagator theory and scattering theory. Limits of the Dirac equation, considered as a wave mechanical equation, are considered. (U.K.)
STUDENTS’ POTENTIAL FOR AUTHENTIC LEADERSHIP
Djurdja Solesa-Grijak; Dragan Solesa; Nedjo Kojic
2015-01-01
To know yourself and to act accordingly has been seen as a moral imperative throughout history. The aim of this research was to determine potential of students for authentic leadership and relation between their authentic personality and potential for authentic leadership. The sample consisted of students (N=133) from Serbia (male – 59% and female – 41%). The average age of students was M=21.9. Instruments used were Authenticity Scale (Wood et al., 2008) and Authentic Leadership Self-Assessme...
Estimation of potential uranium resources
International Nuclear Information System (INIS)
Curry, D.L.
1977-09-01
Potential estimates, like reserves, are limited by the information on hand at the time and are not intended to indicate the ultimate resources. Potential estimates are based on geologic judgement, so their reliability is dependent on the quality and extent of geologic knowledge. Reliability differs for each of the three potential resource classes. It is greatest for probable potential resources because of the greater knowledge base resulting from the advanced stage of exploration and development in established producing districts where most of the resources in this class are located. Reliability is least for speculative potential resources because no significant deposits are known, and favorability is inferred from limited geologic data. Estimates of potential resources are revised as new geologic concepts are postulated, as new types of uranium ore bodies are discovered, and as improved geophysical and geochemical techniques are developed and applied. Advances in technology that permit the exploitation of deep or low-grade deposits, or the processing of ores of previously uneconomic metallurgical types, also will affect the estimates
Vicious walkers in a potential
International Nuclear Information System (INIS)
Bray, Alan J; Winkler, Karen
2004-01-01
We consider N vicious walkers moving in one dimension in a one-body potential v(x). Using the backward Fokker-Planck equation we derive exact results for the asymptotic form of the survival probability Q(x, t) of vicious walkers initially located at (x 1 , ..., x N ) = x, when v(x) is an arbitrary attractive potential. Explicit results are given for a square-well potential with absorbing or reflecting boundary conditions at the walls, and for a harmonic potential with an absorbing or reflecting boundary at the origin and the walkers starting on the positive half line. By mapping the problem of N vicious walkers in zero potential onto the harmonic potential problem, we rederive the results by Fisher (1984 J. Stat. Phys. 34 667) and Krattenthaler et al (2000 J. Phys. A: Math. Gen. 33 8835) respectively for vicious walkers on an infinite line and on a semi-infinite line with an absorbing wall at the origin. This mapping also gives a new result for vicious walkers on a semi-infinite line with a reflecting boundary at the origin: Q(x,t) ∼ t N(N-1)/2
Economic potential of inertial fusion
International Nuclear Information System (INIS)
Nuckolls, J.H.
1984-04-01
Beyond the achievement of scientific feasibility, the key question for fusion energy is: does it have the economic potential to be significantly cheaper than fission and coal energy. If fusion has this high economic potential then there are compelling commercial and geopolitical incentives to accelerate the pace of the fusion program in the near term, and to install a global fusion energy system in the long term. Without this high economic potential, fusion's success depends on the failure of all alternatives, and there is no real incentive to accelerate the program. If my conjectures on the economic potential of inertial fusion are approximately correct, then inertial fusion energy's ultimate costs may be only half to two-thirds those of advanced fission and coal energy systems. Relative cost escalation is not assumed and could increase this advantage. Both magnetic and inertial approaches to fusion potentially have a two-fold economic advantage which derives from two fundamental properties: negligible fuel costs and high quality energy which makes possible more efficient generation of electricity. The wining approach to fusion may excel in three areas: electrical generating efficiency, minimum material costs, and adaptability to manufacture in automated factories. The winning approach must also rate highly in environmental potential, safety, availability factor, lifetime, small 0 and M costs, and no possibility of utility-disabling accidents
Labor potential: enhancing its development
Directory of Open Access Journals (Sweden)
O.P. Melnichuk
2016-06-01
Full Text Available This publication presents the views of the author about the need to expand research of labor potential, estimation of quantitative indicators and qualitative characteristics at the individual, regional levels and the state as a whole to develop the mechanisms of its development. The existing methods of labour potential assessment are mainly based on the probable approach taking into account external and internal factors. In the case of assessment of labour potential of a single enterprise for the most suitable for this production method the mechanisms of its development can be worked out. However, for the state under a certain depreciation of the resource, property, financial and other potentials, aggressive manifestations of the crisis phenomena, processes etc. to resolve urgent is the problem of enhancing the development of qualitative characteristics of labor potential at all its levels. In this context it is important to exploit the potential of domestic education and science which now continue to be reformed for the sake of achieving European standards, using the advanced experience of other countries. Every means of legal, financial, managerial, and organizational impact should be used for this.
On the cusp anomalous dimension in the ladder limit of N=4 SYM
Energy Technology Data Exchange (ETDEWEB)
Beccaria, Matteo; Fachechi, Alberto; Macorini, Guido [Dipartimento di Matematica e Fisica “Ennio De Giorgi”, Università del Salento,Via Arnesano, 73100 Lecce (Italy); INFN,Via Arnesano, 73100 Lecce (Italy)
2016-06-01
We analyze the cusp anomalous dimension in the (leading) ladder limit of N=4 SYM and present new results for its higher-order perturbative expansion. We study two different limits with respect to the cusp angle ϕ. The first is the light-like regime where x=e{sup i} {sup ϕ}→0. This limit is characterised by a non-trivial expansion of the cusp anomaly as a sum of powers of log x, where the maximum exponent increases with the loop order. The coefficients of this expansion have remarkable transcendentality features and can be expressed by products of single zeta values. We show that the whole logarithmic expansion is fully captured by a solvable Woods-Saxon like one-dimensional potential. From the exact solution, we extract generating functions for the cusp anomaly as well as for the various specific transcendental structures appearing therein. The second limit that we discuss is the regime of small cusp angle. In this somewhat simpler case, we show how to organise the quantum mechanical perturbation theory in a novel efficient way by means of a suitable all-order Ansatz for the ground state of the associated Schrödinger problem. Our perturbative setup allows to systematically derive higher-order perturbative corrections in powers of the cusp angle as explicit non-perturbative functions of the effective coupling. This series approximation is compared with the numerical solution of the Schrödinger equation to show that we can achieve very good accuracy over the whole range of coupling and cusp angle. Our results have been obtained by relatively simple techniques. Nevertheless, they provide several non-trivial tests useful to check the application of Quantum Spectral Curve methods to the ladder approximation at non zero ϕ, in the two limits we studied.
Energy Technology Data Exchange (ETDEWEB)
Gautam, Manjeet Singh [Thapar University, School of Physics and Materials Science, Patiala (India); Indus Degree College, Department of Physics, Kinana, Jind, Haryana (India); Grover, Neha; Sharma, Manoj K. [Thapar University, School of Physics and Materials Science, Patiala (India)
2017-01-15
The complete fusion (CF) and incomplete fusion (ICF) cross-sections are estimated for {sup 6,} {sup 7}Li + {sup 159}Tb reactions using the energy-dependent Woods-Saxon potential model (EDWSP model) and dynamical cluster-decay model (DCM). The CF data of the {sup 6}Li + {sup 159}Tb({sup 7}Li + {sup 159}Tb) reaction at above barrier energies is suppressed with reference to expectations of the EDWSP model by 25% (20%) which is smaller than the reported data by ∝ 9% (6%). This suppression is correlated with the projectile breakup effect. The projectiles {sup 6,7}Li are loosely bound systems, which may break up into charged fragments prior to reaching the fusion barrier and subsequently one of the fragment is captured by the target leading to the suppression of fusion data at above barrier energies. The sum of CF and ICF, which is termed as total fusion cross-section (TF), removes the discrepancies between theoretical predictions and the above barrier complete fusion data and hence is adequately explained via the EDWSP model over a wide range of energy spread across the Coulomb barrier. In addition to fusion, the decay mechanism of {sup 6}Li + {sup 159}Tb reaction is studied within the framework of the dynamical cluster-decay model (DCM). The breakup of the projectile ({sup 6}Li) in the entrance channel indicates the presence of ICF, which is investigated further using the collective clusterization approach of DCM. The present theoretical analysis suggests that a larger barrier modification is needed to address the fusion data of chosen reactions in the below barrier energy region. (orig.)
Streaming potential measurements of biosurfaces
Van Wagenen, R. A.; Andrade, J. D.; Hibbs, J. B., Jr.
1976-01-01
A technique based on the measurement of streaming potentials has been developed to evaluate the electrokinetic region of the cell periphery. This approach is feasible for cell lines propagated in in-vitro cell cultures in monolayer form. The advantage of this system is that cells may be evaluated in the living state atttached to a substrate; it is not necessary to subject the cells to enzymatic, chemical, or mechanical trauma required to obtain monodisperse suspensions which are then normally evaluated by microelectrophoresis. In this manner, it should be possible to study the influence of substrate and environmental factors on the charge density and potential at the cell periphery. The apparatus and procedure are described as well as some results concerning the electrokinetic potential of borosilicate capillaries as a function of ionic strength, pH, and temperature. The effect that turbulence and entrance flow conditions have on accurate streaming-potential measurements is discussed. The electrokinetic potential of BALB/c 3T12 fibroblasts has been quantified as a function of pH, ionic strength, glutaraldehyde fixation, and Giemsa staining.
A semiclassical study of optical potentials - potential resonances -
International Nuclear Information System (INIS)
Lee, S.Y.; Takigawa, N.; Marty, C.
1977-01-01
A semiclassical method is used to analyze resonances produced by complex potentials. The absorption plays a central role: when it is not too great, resonances manifest themselves by enhancement of cross sections near π. The reverse is not necessarily true, for instance the anomalous large angle scattering for α-Ca is due to a coherent superposition of many partial waves
Neutron and proton optical potentials
International Nuclear Information System (INIS)
Hansen, L.F.
1985-11-01
The neutron and proton optical model potentials (OMP) are discussed in terms of microscopic (MOMP) and phenomenological (POMP) models. For the MOMP, two approaches are discussed, the nucleus matter approach [Jeukenne-Lejeune-Mahaux (JLM) and Brieva-Rook-von Geramb (BRVG), potentials] and the finite nuclei approach (Osterfeld and Madsen). For the POMP, the Lane charge-exchange potential and its validity over a wide mass range is reviewed. In addition to the Lane symmetry term, the Coulomb correction to both the real and imaginary parts of the OMP is discussed for the above models. The use of the OMP to calculate collective inelastic scattering and observed differences between the neutron- and proton-deformation parameters is also illustrated. 25 refs., 3 figs
Wind energy potential in Bulgaria
International Nuclear Information System (INIS)
Shtrakov, Stanko Vl.
2009-01-01
In this study, wind characteristic and wind energy potential in Bulgaria were analyzed using the wind speed data. The wind energy potential at different sites in Bulgaria has been investigated by compiling data from different sources and analyzing it using a software tool. The wind speed distribution curves were obtained by using the Weibull and Rayleigh probability density functions. The results relating to wind energy potential are given in terms of the monthly average wind speed, wind speed probability density function (PDF), wind speed cumulative density function (CDF), and wind speed duration curve. A technical and economic assessment has been made of electricity generation from three wind turbines having capacity of (60, 200, and 500 kW). The yearly energy output capacity factor and the electrical energy cost of kWh produced by the three different turbines were calculated
Accelerating cosmologies from exponential potentials
International Nuclear Information System (INIS)
Neupane, Ishwaree P.
2003-11-01
It is learnt that exponential potentials of the form V ∼ exp(-2cφ/M p ) arising from the hyperbolic or flux compactification of higher-dimensional theories are of interest for getting short periods of accelerated cosmological expansions. Using a similar potential but derived for the combined case of hyperbolic-flux compactification, we study a four-dimensional flat (or open) FRW cosmologies and give analytic (and numerical) solutions with exponential behavior of scale factors. We show that, for the M-theory motivated potentials, the cosmic acceleration of the universe can be eternal if the spatial curvature of the 4d spacetime is negative, while the acceleration is only transient for a spatially flat universe. We also briefly discuss about the mass of massive Kaluza-Klein modes and the dynamical stabilization of the compact hyperbolic extra dimensions. (author)
Introduction to heat potential theory
Watson, Neil A
2012-01-01
This book is the first to be devoted entirely to the potential theory of the heat equation, and thus deals with time dependent potential theory. Its purpose is to give a logical, mathematically precise introduction to a subject where previously many proofs were not written in detail, due to their similarity with those of the potential theory of Laplace's equation. The approach to subtemperatures is a recent one, based on the Poisson integral representation of temperatures on a circular cylinder. Characterizations of subtemperatures in terms of heat balls and modified heat balls are proved, and thermal capacity is studied in detail. The generalized Dirichlet problem on arbitrary open sets is given a treatment that reflects its distinctive nature for an equation of parabolic type. Also included is some new material on caloric measure for arbitrary open sets. Each chapter concludes with bibliographical notes and open questions. The reader should have a good background in the calculus of functions of several vari...
Potential Theory of Multicomponent Adsorption
DEFF Research Database (Denmark)
Shapiro, Alexander; Stenby, Erling Halfdan
1998-01-01
We developed a theory of multicomponent adsorption on the basis of the potential concept originally suggested by Polanyi. The mixture is considered as a heterogeneous substance segregated in the external field emitted by the adsorbent. The same standard equation of state, with no additional fitting...... parameters, is used for the segregated and for the bulk phases. With this approach, few parameters are needed to correlate pure component adsorption isotherms. These parameters may be used to predict adsorption equilibria of multicomponent mixtures without additional adjustment. A connection between...... the potential theory and the spreading pressure concept is established, and problems of the theory consistency are studied. Numerical algorithms are suggested for evaluation of the segregated state of the mixture in the potential field of adsorption forces. Comparison with experimental data shows good agreement...
The potential of biogas energy
International Nuclear Information System (INIS)
Acaroglu, M.; Hepbasli, A.; Kocar, G.
2005-01-01
Biogas technology has been known about for a long time, but in recent years the interest in it has significantly increased, especially due to the higher costs and the rapid depletion of fossil fuels as well as their environmental considerations. The main objective of the present study is to investigate the potential of biogas energy in the 15 European Union (EU) countries and in Turkey, which is seeking admission to the EU and is trying to meet EU environmental standards. Biogas energy potential of the 15 EU countries is estimated to be about 800 PJ. Besides this, Turkey's annual animal waste potential is obtained to be about 11.81 million tons with a biogas energy equivalent of 53.6 PJ. It is expected that this study will be helpful in developing highly applicable and productive planning for energy policies towards the optimum utilization of biogas energy. (author)
Handbook methane potential; Handbok metanpotential
Energy Technology Data Exchange (ETDEWEB)
Carlsson, My (AnoxKaldnes AB (Sweden)); Schnurer, Anna (Swedish Univ. of Agricultural Sciences, Uppsala (Sweden))
2011-07-15
Before using a organic material for biogas production it is essential to evaluate the methane production potential. The methane potential is one important tool possible to use during planning of new plants but also when new materials are considered for already running biogas plants. The chemical composition of different organic material varies extensively and this will have an impact on both the degradability and the methane potential. Information about the methane potential of a specific material can sometimes be found in the literature or can be calculated after a chemical/ physical or biological characterization. Here, the BMP test (Biochemical Methane Potential) is a commonly used method. Today the BMP test is a commonly used method to determine the methane potential. Many national and international research groups, consultants as well as personal at biogas plants are using this method and there is a lot of data available in the literature from such tests. In addition there are several protocols giving guidelines on how to execute a BMP-test. The BMP-test is performed in many different ways, not always under optimized conditions, and there is a lack of information on how to interpret the obtained data. This report summarizes knowledge from the literature and the experience from a Swedish referee group, consisting of persons being active performers of BMP-tests. The report does not include a standardized protocol as the procedure can be performed in different ways depending on available equipment and on the type of material to be tested. Instead the report discusses different factors of great importance for a successful test giving reliable results. The report also summarizes important information concerning the interpretation and how to present results in order to allow comparison of data from different test.
Potential problems with interpolating fields
Energy Technology Data Exchange (ETDEWEB)
Birse, Michael C. [The University of Manchester, Theoretical Physics Division, School of Physics and Astronomy, Manchester (United Kingdom)
2017-11-15
A potential can have features that do not reflect the dynamics of the system it describes but rather arise from the choice of interpolating fields used to define it. This is illustrated using a toy model of scattering with two coupled channels. A Bethe-Salpeter amplitude is constructed which is a mixture of the waves in the two channels. The potential derived from this has a strong repulsive core, which arises from the admixture of the closed channel in the wave function and not from the dynamics of the model. (orig.)
Tunnel superpenetrability of potential barriers
International Nuclear Information System (INIS)
Zakhariev, B N.
1982-01-01
The transmission of two particles through the same barrier is considered. The limiting cases are compared when the particles are joined together in a single particle with double mass-energy and potential and when they pass the barrier independently. As an intermediate case a pair of particles bound in a quasideuteron of a finite size is considered. It is shown that long-range collective correlations of particles (of the superfluidity type and others) simplify very much for them passing through high potential barriers. This happens due to the transfer of the additional energy from the particles outside the barriers to those inside it
Potential Applications of Manual Games,
1984-02-01
34 just because some electronic equipment is used to keep track of logistics, combat results, and force status. Even a highly computerized game like...D-A152 541 POTENTIAL APPLICATIONS OF MANUAL GAMES (U) RAND CORP ii SANTA MONICA CA T A BROW~N FEB 84 RAND/P-6957 UNCLASI7FIED F/G 12/2 N El..I 111 1...128 112.5 111 m; * _ 1.8 I1111 ’I’ll MICROCOPY RESOLUTION TEST CHART NATI NAl fii~ t1 RI 1A L4k, I POTENTIAL APPLICATIONS OF MANUJAL GAMES Lfl N Lfl
Diatomic interaction potential theory applications
Goodisman, Jerry
2013-01-01
Diatomic Interaction Potential Theory, Volume 2: Applications discusses the variety of applicable theoretical material and approaches in the calculations for diatomic systems in their ground states. The volume covers the descriptions and illustrations of modern calculations. Chapter I discusses the calculation of the interaction potential for large and small values of the internuclear distance R (separated and united atom limits). Chapter II covers the methods used for intermediate values of R, which in principle means any values of R. The Hartree-Fock and configuration interaction schemes des
Effective potential models for hadrons
International Nuclear Information System (INIS)
Lucha, W.
1995-12-01
The aim of these lectures is to give a self-contained introduction to nonrelativistic potential models, to their formulation as well as to their possible applications. At the price of some lack of (in a mathematical sense) rigorous derivations, we try to give a feeling and understanding for the simplest conceivable method to extract the explicit form of the forces acting between quarks from the interplay between experimental observations and theoretical considerations. According to this spirit, we demonstrate, in detail, how to obtain the underlying Hamiltonian and how to determine the Lorentz structure of the quark-(anti-)quark interaction potential from well-established experimental facts. (author)
Global warming potential of pavements
Energy Technology Data Exchange (ETDEWEB)
Santero, Nicholas J [Department of Civil and Environmental Engineering, 407 McLaughlin Hall, University of California, Berkeley, CA 94720-1712 (United States); Horvath, Arpad, E-mail: njsantero@cal.berkeley.ed, E-mail: horvath@ce.berkeley.ed [Department of Civil and Environmental Engineering, 215B McLaughlin Hall, University of California, Berkeley, CA 94720-1712 (United States)
2009-09-15
Pavements comprise an essential and vast infrastructure system supporting our transportation network, yet their impact on the environment is largely unquantified. Previous life-cycle assessments have only included a limited number of the applicable life-cycle components in their analysis. This research expands the current view to include eight different components: materials extraction and production, transportation, onsite equipment, traffic delay, carbonation, lighting, albedo, and rolling resistance. Using global warming potential as the environmental indicator, ranges of potential impact for each component are calculated and compared based on the information uncovered in the existing research. The relative impacts between components are found to be orders of magnitude different in some cases. Context-related factors, such as traffic level and location, are also important elements affecting the impacts of a given component. A strategic method for lowering the global warming potential of a pavement is developed based on the concept that environmental performance is improved most effectively by focusing on components with high impact potentials. This system takes advantage of the fact that small changes in high-impact components will have more effect than large changes in low-impact components.
Global warming potential of pavements
International Nuclear Information System (INIS)
Santero, Nicholas J; Horvath, Arpad
2009-01-01
Pavements comprise an essential and vast infrastructure system supporting our transportation network, yet their impact on the environment is largely unquantified. Previous life-cycle assessments have only included a limited number of the applicable life-cycle components in their analysis. This research expands the current view to include eight different components: materials extraction and production, transportation, onsite equipment, traffic delay, carbonation, lighting, albedo, and rolling resistance. Using global warming potential as the environmental indicator, ranges of potential impact for each component are calculated and compared based on the information uncovered in the existing research. The relative impacts between components are found to be orders of magnitude different in some cases. Context-related factors, such as traffic level and location, are also important elements affecting the impacts of a given component. A strategic method for lowering the global warming potential of a pavement is developed based on the concept that environmental performance is improved most effectively by focusing on components with high impact potentials. This system takes advantage of the fact that small changes in high-impact components will have more effect than large changes in low-impact components.
Exponential Potential versus Dark Matter
1993-10-15
scale of the solar system. Galaxy, Dark matter , Galaxy cluster, Gravitation, Quantum gravity...A two parameter exponential potential explains the anomalous kinematics of galaxies and galaxy clusters without need for the myriad ad hoc dark ... matter models currently in vogue. It also explains much about the scales and structures of galaxies and galaxy clusters while being quite negligible on the
Riesz potential versus fractional Laplacian
Ortigueira, Manuel Duarte
2014-09-01
This paper starts by introducing the Grünwald-Letnikov derivative, the Riesz potential and the problem of generalizing the Laplacian. Based on these ideas, the generalizations of the Laplacian for 1D and 2D cases are studied. It is presented as a fractional version of the Cauchy-Riemann conditions and, finally, it is discussed with the n-dimensional Laplacian.
Assessment of triton potential energy
International Nuclear Information System (INIS)
Friar, J.L.; Payne, G.L.
1995-01-01
An assessment is made of the dominant features contributing to the triton potential energy, with the objective of understanding qualitatively their origins and sensitivities. Relativistic effects, short-range repulsion, and OPEP dominance are discussed. A determination of the importance of various regions of nucleon-nucleon separation is made numerically. (author)
Sports Potentials for Physical Fitness.
Clarke, H. Harrison, Ed.
1978-01-01
This report, one of a series on research into specific physical activities and their efficacy in improving and maintaining physical fitness, examines sport participation and the potential it has for developing muscular strength, muscular endurance, and circulatory-respiratory endurance. The activities consist primarily of the following twelve…
Evolutionary potential games on lattices
International Nuclear Information System (INIS)
Szabó, György; Borsos, István
2016-01-01
Game theory provides a general mathematical background to study the effect of pair interactions and evolutionary rules on the macroscopic behavior of multi-player games where players with a finite number of strategies may represent a wide scale of biological objects, human individuals, or even their associations. In these systems the interactions are characterized by matrices that can be decomposed into elementary matrices (games) and classified into four types. The concept of decomposition helps the identification of potential games and also the evaluation of the potential that plays a crucial role in the determination of the preferred Nash equilibrium, and defines the Boltzmann distribution towards which these systems evolve for suitable types of dynamical rules. This survey draws parallel between the potential games and the kinetic Ising type models which are investigated for a wide scale of connectivity structures. We discuss briefly the applicability of the tools and concepts of statistical physics and thermodynamics. Additionally the general features of ordering phenomena, phase transitions and slow relaxations are outlined and applied to evolutionary games. The discussion extends to games with three or more strategies. Finally we discuss what happens when the system is weakly driven out of the “equilibrium state” by adding non-potential components representing games of cyclic dominance.
Being a potentially responsible party
International Nuclear Information System (INIS)
Ronan, J.T.
1989-01-01
This paper reports on CERCLA II- ability for the unlucky potentially responsible parties (PRPs) which is a Draconian form of strict, joint and several liability with limited statutory defenses that in most cases are impossible to establish. CERCLA vigorously employs these legal concepts, stretching a PRP's financial exposure to the limits necessary to meet the enormous financial costs of remediation
High Potentials: A CEO Perspective
Hermans, Jeanine
2007-01-01
Finding high potentials has been identified as one of the major challenges for society and for higher education. But how does one find the talented individuals who will design the future of society? Can and should universities cooperate or compete with business and industry for these talents? Three CEOs reflect on this worldwide competition for…
Evolutionary potential games on lattices
Energy Technology Data Exchange (ETDEWEB)
Szabó, György, E-mail: szabo@mfa.kfki.hu; Borsos, István, E-mail: borsos@mfa.kfki.hu
2016-04-05
Game theory provides a general mathematical background to study the effect of pair interactions and evolutionary rules on the macroscopic behavior of multi-player games where players with a finite number of strategies may represent a wide scale of biological objects, human individuals, or even their associations. In these systems the interactions are characterized by matrices that can be decomposed into elementary matrices (games) and classified into four types. The concept of decomposition helps the identification of potential games and also the evaluation of the potential that plays a crucial role in the determination of the preferred Nash equilibrium, and defines the Boltzmann distribution towards which these systems evolve for suitable types of dynamical rules. This survey draws parallel between the potential games and the kinetic Ising type models which are investigated for a wide scale of connectivity structures. We discuss briefly the applicability of the tools and concepts of statistical physics and thermodynamics. Additionally the general features of ordering phenomena, phase transitions and slow relaxations are outlined and applied to evolutionary games. The discussion extends to games with three or more strategies. Finally we discuss what happens when the system is weakly driven out of the “equilibrium state” by adding non-potential components representing games of cyclic dominance.
Health Educational Potentials of Technologies.
Magnussen, Rikke; Aagaard-Hansen, Jens
2012-01-01
The field of health promotion technology has been in an exponential growth in recent years and smart phone applications, exer-games and self-monitoring devices has become part of fitness activities and health education. In this work-in-progress-paper theoretical perspectives for categorising and analysing health educational potentials of technologies are presented.
Event horizon and scalar potential
International Nuclear Information System (INIS)
Duruisseau, J.P.; Tonnelat, M.A.
1977-01-01
The introduction of a scalar potential with a more general scheme than General Relativity eliminates the event horizon. Among possible solutions, the Schwarzschild one represents a singular case. A study of the geodesic properties of the matching with an approximated interior solution are given. A new definition of the gravitational mass and chi function is deduced. (author)
Potential theory for directed networks.
Directory of Open Access Journals (Sweden)
Qian-Ming Zhang
Full Text Available Uncovering factors underlying the network formation is a long-standing challenge for data mining and network analysis. In particular, the microscopic organizing principles of directed networks are less understood than those of undirected networks. This article proposes a hypothesis named potential theory, which assumes that every directed link corresponds to a decrease of a unit potential and subgraphs with definable potential values for all nodes are preferred. Combining the potential theory with the clustering and homophily mechanisms, it is deduced that the Bi-fan structure consisting of 4 nodes and 4 directed links is the most favored local structure in directed networks. Our hypothesis receives strongly positive supports from extensive experiments on 15 directed networks drawn from disparate fields, as indicated by the most accurate and robust performance of Bi-fan predictor within the link prediction framework. In summary, our main contribution is twofold: (i We propose a new mechanism for the local organization of directed networks; (ii We design the corresponding link prediction algorithm, which can not only testify our hypothesis, but also find out direct applications in missing link prediction and friendship recommendation.
Determination of nominal accelerating potential
International Nuclear Information System (INIS)
Nizin, P.; Kase, K.
1986-01-01
We present a simple linear relationship between the nominal accelerating potential (NAP) and the ratios of ionization measurements made with constant source--detector distance and at two different phantom thicknesses. This relationship can be used as a standard, unambiguous method for determining NAP for use in dosimetry and quality control
Evolutionary potential games on lattices
Szabó, György; Borsos, István
2016-04-01
Game theory provides a general mathematical background to study the effect of pair interactions and evolutionary rules on the macroscopic behavior of multi-player games where players with a finite number of strategies may represent a wide scale of biological objects, human individuals, or even their associations. In these systems the interactions are characterized by matrices that can be decomposed into elementary matrices (games) and classified into four types. The concept of decomposition helps the identification of potential games and also the evaluation of the potential that plays a crucial role in the determination of the preferred Nash equilibrium, and defines the Boltzmann distribution towards which these systems evolve for suitable types of dynamical rules. This survey draws parallel between the potential games and the kinetic Ising type models which are investigated for a wide scale of connectivity structures. We discuss briefly the applicability of the tools and concepts of statistical physics and thermodynamics. Additionally the general features of ordering phenomena, phase transitions and slow relaxations are outlined and applied to evolutionary games. The discussion extends to games with three or more strategies. Finally we discuss what happens when the system is weakly driven out of the "equilibrium state" by adding non-potential components representing games of cyclic dominance.
Riesz potential versus fractional Laplacian
Ortigueira, Manuel Duarte; Laleg-Kirati, Taous-Meriem; Machado, José Antó nio Tenreiro
2014-01-01
This paper starts by introducing the Grünwald-Letnikov derivative, the Riesz potential and the problem of generalizing the Laplacian. Based on these ideas, the generalizations of the Laplacian for 1D and 2D cases are studied. It is presented as a fractional version of the Cauchy-Riemann conditions and, finally, it is discussed with the n-dimensional Laplacian.
Tank farm potential ignition sources
International Nuclear Information System (INIS)
Scaief, C.C. III.
1996-01-01
This document identifies equipment, instrumentation, and sensors that are located in-tank as well as ex-tank in areas that may have communication paths with the tank vapor space. For each item, and attempt is made to identify the potential for ignition of flammable vapors using a graded approach. The scope includes all 177 underground storage tanks
Wind energy potential in India
International Nuclear Information System (INIS)
Rangarajan, S.
1995-01-01
Though located in the tropics, India is endowed with substantial wind resources because of its unique geographical location which gets fully exposed to both the south-west and north-east monsoon winds. The westerly winds of the south-west monsoons provide bulk of the wind potential. Areas with mean annual wind speed exceeding 18 k mph and areas with mean annual power density greater than 140 W/m 2 have been identified using the wind data collected by the wind monitoring project funded by the Ministry of Non-conventional Energy Sources (MNES). Seasonal variations in wind speed at selected locations are discussed as also the frequency distribution of hourly wind speed. Annual capacity factors for 250 kW wind electric generators have been calculated for several typical locations. A good linear correlation has been found between mean annual wind speed and mean annual capacity factor. A method is described for assessing wind potential over an extended region where adequate data is available. It is shown that the combined wind energy potential over five selected areas of limited extent in Gujarat, Andhra Pradesh and Tamil Nadu alone amounts to 22,000 MW under the assumption of 20 per cent land availability for installing wind farms. For a higher percentage of land availability, the potential will be correspondingly higher. (author). 12 refs., 6 figs., 3 tabs
Bitcoin's Potential for Going Mainstream
Kasiyanto, Safari
2016-01-01
This paper reviews the possibility of bringing Bitcoin into the mainstream. In so doing, it elaborates the potential and obstacles of the Bitcoin system and what it would take for it to go mainstream. A cross-cutting discussion provides a helicopter view and encompasses the technical, economic,
Potential Theory for Directed Networks
Zhang, Qian-Ming; Lü, Linyuan; Wang, Wen-Qiang; Zhou, Tao
2013-01-01
Uncovering factors underlying the network formation is a long-standing challenge for data mining and network analysis. In particular, the microscopic organizing principles of directed networks are less understood than those of undirected networks. This article proposes a hypothesis named potential theory, which assumes that every directed link corresponds to a decrease of a unit potential and subgraphs with definable potential values for all nodes are preferred. Combining the potential theory with the clustering and homophily mechanisms, it is deduced that the Bi-fan structure consisting of 4 nodes and 4 directed links is the most favored local structure in directed networks. Our hypothesis receives strongly positive supports from extensive experiments on 15 directed networks drawn from disparate fields, as indicated by the most accurate and robust performance of Bi-fan predictor within the link prediction framework. In summary, our main contribution is twofold: (i) We propose a new mechanism for the local organization of directed networks; (ii) We design the corresponding link prediction algorithm, which can not only testify our hypothesis, but also find out direct applications in missing link prediction and friendship recommendation. PMID:23408979
Electromagnetic potentials without gauge transformations
International Nuclear Information System (INIS)
Chubykalo, A; Espinoza, A; Alvarado Flores, R
2011-01-01
In this paper, we show that the use of the Helmholtz theorem enables the derivation of uniquely determined electromagnetic potentials without the necessity of using gauge transformation. We show that the electromagnetic field comprises two components, one of which is characterized by instantaneous action at a distance, whereas the other propagates in retarded form with the velocity of light. In our attempt to show the superiority of the new proposed method to the standard one, we argue that the action-at-a-distance components cannot be considered as a drawback of our method, because the recommended procedure for eliminating the action at a distance in the Coulomb gauge leads to theoretical subtleties that allow us to say that the needed gauge transformation is not guaranteed. One of the theoretical consequences of this new definition is that, in addition to the electric E and magnetic B fields, the electromagnetic potentials are real physical quantities. We show that this property of the electromagnetic potentials in quantum mechanics is also a property of the electromagnetic potentials in classical electrodynamics.
The hydrogeothermal potential of Southern Hesse; Das hydrogeothermische Potential Suedhessens
Energy Technology Data Exchange (ETDEWEB)
Fitzer, C; Fluhrer, S; Sanner, B; Knoblich, K [Giessen Univ. (Germany). Inst. fuer Angewandte Geowissenschaften
1997-12-01
The paper investigates rock series suited as storage media and the temperature distribution in the subsurface of Southern Hesse. It gives an idea of the possibilities for hydrogeothermal energy use in the area. The densily populated Rhein-Main-region provides a good demand potential for geothermal heat. A substantially elevated geothermal gradient of about 60 K/km as compared to the continental average of 30 K/km could be demonstrated in the northern part of the Upper Rhine Graben. Thermal anomalies could be localised. The Rotliegend-layers (Perm) provide the highest geothermal ressources in the region. In more shallow depth, the Hydrobia layers (Teritary) show reasonable values. To the north, the potential of these series decreases. Hence hydrogeothermal energy use should not be considered in the northern part of Southern Hesse. The highest potential can be expected from the Rotliegend layers in the area of Stockstadt and Biebesheim. (orig.) [Deutsch] Die Untersuchung geht auf die moeglichen Speichergesteine und die Temperaturverteilung im Untergrund Suedhessens ein und gibt einen ersten Eindruck von den Moeglichkeiten zur Nutzung der Hydrogeothermie in der Region. Fuer geothermische Waerme besteht im dicht besiedelten Rhein-Main-Gebiet eine gute Abnehmerstruktur. Im noerdlichen Oberrheingraben konnte im Mittel ein deutlich erhoehter Temperaturgradient von etwa 60 K/km gegenueber dem kontinentalen Krustendurchschnittswert von 30 K/km nachgewiesen werden. Waemeanomalien wurden lokalisiert. Die Rotliegendschichten weisen im untersuchten Gebiet eindeutig die hoechsten Ressourcen auf. In geringerer Tiefenlage erzielen die Hydrobienschichten noch beachtliche Werte. Nach Norden nimmt das Potential der Schichten ab. Daher ist von einer Nutzung der Hydrogeothermie im noerdlichen Bereich Suedhessens eher abzuraten. Die hoechsten Ressourcen in Suedhessen sind im Bereich von Stockstadt und Biebesheim in den Rotliegenschichten zu erwarten. (orig.)
Decoupling Action Potential Bias from Cortical Local Field Potentials
Directory of Open Access Journals (Sweden)
Stephen V. David
2010-01-01
Full Text Available Neurophysiologists have recently become interested in studying neuronal population activity through local field potential (LFP recordings during experiments that also record the activity of single neurons. This experimental approach differs from early LFP studies because it uses high impendence electrodes that can also isolate single neuron activity. A possible complication for such studies is that the synaptic potentials and action potentials of the small subset of isolated neurons may contribute disproportionately to the LFP signal, biasing activity in the larger nearby neuronal population to appear synchronous and cotuned with these neurons. To address this problem, we used linear filtering techniques to remove features correlated with spike events from LFP recordings. This filtering procedure can be applied for well-isolated single units or multiunit activity. We illustrate the effects of this correction in simulation and on spike data recorded from primary auditory cortex. We find that local spiking activity can explain a significant portion of LFP power at most recording sites and demonstrate that removing the spike-correlated component can affect measurements of auditory tuning of the LFP.
On the dynamics of gauge potential
International Nuclear Information System (INIS)
Tao Jiafu; Li Yuanjie; Zhang Jinru
1992-01-01
The gauge potential is resolved into gauge potential of strength and gauge potential of phase. The phase gauge potential can be described with an equivalent potential of inertial force. A Lagrangian density with phase gauge potential is given and some examples are discussed. The method proposed has been extended to the case of the non-Abelian group
The Biodiversity Informatics Potential Index
2011-01-01
Background Biodiversity informatics is a relatively new discipline extending computer science in the context of biodiversity data, and its development to date has not been uniform throughout the world. Digitizing effort and capacity building are costly, and ways should be found to prioritize them rationally. The proposed 'Biodiversity Informatics Potential (BIP) Index' seeks to fulfill such a prioritization role. We propose that the potential for biodiversity informatics be assessed through three concepts: (a) the intrinsic biodiversity potential (the biological richness or ecological diversity) of a country; (b) the capacity of the country to generate biodiversity data records; and (c) the availability of technical infrastructure in a country for managing and publishing such records. Methods Broadly, the techniques used to construct the BIP Index were rank correlation, multiple regression analysis, principal components analysis and optimization by linear programming. We built the BIP Index by finding a parsimonious set of country-level human, economic and environmental variables that best predicted the availability of primary biodiversity data accessible through the Global Biodiversity Information Facility (GBIF) network, and constructing an optimized model with these variables. The model was then applied to all countries for which sufficient data existed, to obtain a score for each country. Countries were ranked according to that score. Results Many of the current GBIF participants ranked highly in the BIP Index, although some of them seemed not to have realized their biodiversity informatics potential. The BIP Index attributed low ranking to most non-participant countries; however, a few of them scored highly, suggesting that these would be high-return new participants if encouraged to contribute towards the GBIF mission of free and open access to biodiversity data. Conclusions The BIP Index could potentially help in (a) identifying countries most likely to
Hemolytic potential of hydrodynamic cavitation.
Chambers, S D; Bartlett, R H; Ceccio, S L
2000-08-01
The purpose of this study was to determine the hemolytic potentials of discrete bubble cavitation and attached cavitation. To generate controlled cavitation events, a venturigeometry hydrodynamic device, called a Cavitation Susceptibility Meter (CSM), was constructed. A comparison between the hemolytic potential of discrete bubble cavitation and attached cavitation was investigated with a single-pass flow apparatus and a recirculating flow apparatus, both utilizing the CSM. An analytical model, based on spherical bubble dynamics, was developed for predicting the hemolysis caused by discrete bubble cavitation. Experimentally, discrete bubble cavitation did not correlate with a measurable increase in plasma-free hemoglobin (PFHb), as predicted by the analytical model. However, attached cavitation did result in significant PFHb generation. The rate of PFHb generation scaled inversely with the Cavitation number at a constant flow rate, suggesting that the size of the attached cavity was the dominant hemolytic factor.
Potential therapeutic applications of biosurfactants.
Gudiña, Eduardo J; Rangarajan, Vivek; Sen, Ramkrishna; Rodrigues, Lígia R
2013-12-01
Biosurfactants have recently emerged as promising molecules for their structural novelty, versatility, and diverse properties that are potentially useful for many therapeutic applications. Mainly due to their surface activity, these molecules interact with cell membranes of several organisms and/or with the surrounding environments, and thus can be viewed as potential cancer therapeutics or as constituents of drug delivery systems. Some types of microbial surfactants, such as lipopeptides and glycolipids, have been shown to selectively inhibit the proliferation of cancer cells and to disrupt cell membranes causing their lysis through apoptosis pathways. Moreover, biosurfactants as drug delivery vehicles offer commercially attractive and scientifically novel applications. This review covers the current state-of-the-art in biosurfactant research for therapeutic purposes, providing new directions towards the discovery and development of molecules with novel structures and diverse functions for advanced applications. Copyright © 2013 Elsevier Ltd. All rights reserved.
In plant corrosion potential monitoring
International Nuclear Information System (INIS)
Rosborg, B.; Molander, A.
1997-01-01
Examples of in plant redox and corrosion potential monitoring in light water reactors are given. All examples are from reactors in Sweden. The measurements have either been performed in side-stream autoclaves connected to the reactor systems by sampling lines, or in-situ in the system piping itself. Potential monitoring can give quite different results depending upon the experimental method. For environments with small concentrations of oxidants sampling lines can introduce large errors. During such circumstances in-situ measurements are necessary. Electrochemical monitoring is a valuable technique as a complement to conventional water chemistry follow-up in plants. It can be used for water chemistry surveillance and can reveal unintentional and harmful water chemistry transients. (author). 15 figs
Kleptomania and Potential Exacerbating Factors
2011-01-01
Kleptomania is an impulse control disorder that can cause significant impairment and serious consequences. Often, the condition is kept secret by the patient, and usually help is sought only when confronted by the legal consequences of the impulsive behaviors. Historically, kleptomania has been viewed from a psychodynamic perspective, and the mainstay of treatment has been psychotherapy. Recently, attempts to explain kleptomania within a neuropsychiatric paradigm have highlighted the possible links between mood disorders, addictive behaviors, and brain injury with kleptomania. These associations with kleptomania can be extrapolated to pharmacological strategies that can potentially help in treating kleptomania. A case of kleptomania, which was potentially exacerbated by multiple factors, will be reviewed. Treatment modalities used in this case, including the use of the Yale-Brown Obsessive Compulsive Scale as a surrogate marker to gauge response to treatment, will be discussed. PMID:22132369
Metasynthesis findings: potential versus reality.
Finfgeld-Connett, Deborah
2014-11-01
Early on, qualitative researchers predicted that metasynthesis research had the potential to significantly push knowledge development forward. More recently, scholars have questioned whether this is actually occurring. To examine this concern, a randomly selected sample of metasynthesis articles was systematically reviewed to identify the types of findings that have been produced. Based on this systematic examination, it appears that findings from metasynthesis investigations might not be reaching their full potential. Metasynthesis investigations frequently result in isolated findings rather than findings in relationship, and opportunities to generate research hypotheses and theoretical models are not always fully realized. With this in mind, methods for moving metasynthesis findings into relationship are discussed. © The Author(s) 2014.
International Nuclear Information System (INIS)
Hauge Madsen, P.; Lundsager, P.
1992-09-01
Papers presented at the European wind energy conference on the potential of wind farms are presented. The aim of the conference was to bring into focus the problems, experiences and potential of the application of wind power in wind power farms as a contribution to the European and global energy supply. It was considered that the interchange of experience among representatives of science, utilities, industry, environment and energy planning, together with those who represent financial and insurance interests, would create a better understanding of all aspects of wind power for its future successful development. The subjects covered concern surveys of national planning and policies regarding wind energy utilization and national and global development of wind turbine arrays. The performance of some individual wind farms is described. Papers also deal with utility and project planning, wind prediction and certification, wind loads and fatigues, wakes, noise and control. (AB)
In plant corrosion potential monitoring
Energy Technology Data Exchange (ETDEWEB)
Rosborg, B; Molander, A [Studsvik Material AB, Nykoeping (Sweden)
1997-02-01
Examples of in plant redox and corrosion potential monitoring in light water reactors are given. All examples are from reactors in Sweden. The measurements have either been performed in side-stream autoclaves connected to the reactor systems by sampling lines, or in-situ in the system piping itself. Potential monitoring can give quite different results depending upon the experimental method. For environments with small concentrations of oxidants sampling lines can introduce large errors. During such circumstances in-situ measurements are necessary. Electrochemical monitoring is a valuable technique as a complement to conventional water chemistry follow-up in plants. It can be used for water chemistry surveillance and can reveal unintentional and harmful water chemistry transients. (author). 15 figs.
International Nuclear Information System (INIS)
Hauge Madsen, P.; Lundsager, P.
1992-09-01
Papers presented at the European wind energy conference on the potential of wind farms are presented. The aim of the conference was to bring into focus the problems, experiences and potential of the application of wind power in wind power farms as a contribution to the European and global energy supply. It was considered that the interchange of experience among representatives of science, utilities, industry, environment and energy planning, together with those who represent financial and insurance interests, would create a better understanding of all aspects of wind power for its future successful development. The subjects covered concern surveys of national planning and policies regarding wind energy utilization and national and global development of wind turbine arrays. The performance of some individual wind farms is described. Papers also deal with utility and project planning, wind prediction and certification, wind loads and fatigus, wakes, noise and control. (AB)
Virtual materiality, potentiality and subjctivity
DEFF Research Database (Denmark)
Søndergaard, Dorte Marie
2013-01-01
, of movies and of dreams as they enter intra-activities in the comprehensive set of apparatuses that enact child agency, subjectivity and relational practices. The analyses and conceptual refinements are based on empirical cases involving interviews with and observations among 8-14 year old children.......How do we conceptualize virtual materiality, in terms of for instance avatars and weapons in computer games, virtual discourse and subjectivity as phenomena intra-acting with real life materiality, discourse and subjectivity in children’s everyday lives? How do we understand the intra......-activity of such elements in children’s night dreams? These are some of the questions discussed in this text. I bring together Karen Barad’s agential realism and Giorgi Agamben’s concept of potentiality to enable and refine an analytical approach to real-virtual enactments, thereby questioning the potentialities of gaming...
Crystal potential retrieval in HRTEM
International Nuclear Information System (INIS)
Beeching, M.J.; Spargo, A.E.C.
1993-01-01
A possible method for obtaining the crystal potential by inversion of the complex wavefield at the exit surface of the specimen, based on reversal of the multi-slice algorithm, is outlined. Results from preliminary testing of the method using computer simulated data are presented and appear promising, although the limits of applicability of the method are yet to be defined. 13 refs., 5 figs
ADVERGAMES: CHARACTERISTICS, LIMITATIONS AND POTENTIAL
Directory of Open Access Journals (Sweden)
Gurau Calin
2010-07-01
Full Text Available Advergames represent a new advertising concept that uses Internet technology to implement viral marketing campaigns. Despite the potential of this interactive advertising method, very few academic studies have been initiated to investigate the characteristics of advergames, and their influence on consumers’ perceptions and behaviour. Using secondary data, this paper attempts to evaluate the characteristics of effective advergames, and to analyse the effect of advergames on players’ perceptions and behaviour.
Potentials in N=2 supergravity
International Nuclear Information System (INIS)
Zinov'ev, Yu.M.
1985-01-01
The potentials and Yukava interactions, that arise while introducing a gauge interaction of vector and scalar multiplets in N=2 supergravity are presented, in this the gauge group may be either compact or noncompact. The scalar multiplets geometry corresponds to nonlinear σ, models of the form Sp(2,2n)/Sp(2)xSp(2n), SU(2,n)/SU(2)SU(n)xU(1) and O(4,n)/O(4)xO(n)
Wavepacket scattering in potential theory
International Nuclear Information System (INIS)
Weber, T.A.; Hammer, C.L.
1977-01-01
A contour integration technique is developed which enforces the initial conditions for wavepacket-potential scattering. The expansion coefficients for the exact energy eigenstate expansion are automatically expressed in terms of the plane wave expansion coefficients of the initial wavepacket, thereby simplifying what is usually a tedious, mathematical process. The method is applicable regardless of the initial spatial separation of the wavepacket from the scattering center
A relativistic quarkonium potential model
International Nuclear Information System (INIS)
Klima, B.; Maor, U.
1984-04-01
We review a recently developed relativistic quark-antiquark bound state equation using the expansion in intermediate states. Using a QCD motivated potential we succeeded very well to fit both the heavy systems (banti b, canti c) and the light systems (santi s, uanti u and danti d). Here we emphasize our results on heavy-light sustems and on the possible (tanti t) family. (orig.)
Nuclear energy: potentiality and implications
International Nuclear Information System (INIS)
Bahgat, Gawdat
2008-01-01
After a discussion about a broad definition of energy security and about the main challenges facing a potential nuclear renaissance, the article analyses how the European Union and the United States have addressed these challenges. There is no doubt that nuclear power will remain an important component of global energy mix, but it should not be seen as a panacea to the flows in the global energy markets [it
Potential energy function of CN-
Czech Academy of Sciences Publication Activity Database
Špirko, Vladimír; Polák, Rudolf
2008-01-01
Roč. 248, č. 1 (2008), s. 77-80 ISSN 0022-2852 R&D Projects: GA MŠk LC512; GA AV ČR IAA400550511; GA AV ČR IAA400400504 Institutional research plan: CEZ:AV0Z40550506; CEZ:AV0Z40400503 Keywords : potential energy curve * fundamental transition * spectroscopic constants Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 1.636, year: 2008
Potential Psychiatric Uses for MDMA
Yazar?Klosinski, BB; Mithoefer, MC
2017-01-01
Phase II trials of 3,4?methylenedioxymethamphetamine (MDMA)?assisted psychotherapy have demonstrated initial safety and efficacy for treatment of posttraumatic stress disorder (PTSD), with potential for expansion to depression and anxiety disorders. In these trials, single doses of MDMA are administered in a model of medication?assisted psychotherapy, differing from trials involving daily drug administration without psychotherapy. This model presents an opportunity to utilize accelerated regu...
Geothermal Direct Heat Application Potential
Energy Technology Data Exchange (ETDEWEB)
Lienau, Paul J
1989-01-01
The geothermal direct-use industry growth trends, potential, needs, and how they can be met, are addressed. Recent investigations about the current status of the industry and the identification of institutional and technical needs provide the basis on which this paper is presented. Initial drilling risk is the major obstacle to direct-use development. The applications presented include space and district heating projects, heat pumps (heating and cooling), industrial processes, resorts and pools, aquaculture and agriculture.
Aggregate Supply and Potential Output
Razin, Assaf
2004-01-01
The New-Keynesian aggregate supply derives from micro-foundations an inflation-dynamics model very much like the tradition in the monetary literature. Inflation is primarily affected by: (i) economic slack; (ii) expectations; (iii) supply shocks; and (iv) inflation persistence. This paper extends the New Keynesian aggregate supply relationship to include also fluctuations in potential output, as an additional determinant of the relationship. Implications for monetary rules and to the estimati...
Electromagnetic heavy-lepton pair production in relativistic heavy-ion collisions
Energy Technology Data Exchange (ETDEWEB)
Senguel, M.Y. [Atakent Mahallesi, 3. Etap, Halkali-Kuecuekcekmece, Istanbul (Turkey); Gueclue, M.C.; Mercan, Oe.; Karakus, N.G. [istanbul Technical University, Faculty of Science and Letters, Istanbul (Turkey)
2016-08-15
We calculate the cross sections of electromagnetic productions of muon- and tauon-pair productions from the ultra-relativistic heavy ion collisions. Since the Compton wavelengths of muon and tauon are comparable to the radius of the colliding ions, nuclear form factors play important roles for calculating the cross sections. Recent measurement (Abrahamyan et al., Phys Rev Lett 108:112502, 2012) indicates that the neutrons are differently distributed from the protons; therefore this affects the cross section of the heavy-lepton pair production. In order to see the effects of the neutron distributions in the nucleus, we used analytical expression of the Fourier transforms of the Wood-Saxon distribution. Cross section calculations show that the Wood-Saxon distribution function is more sensitive to the parameter R compared to the parameter a. (orig.)
Whole Protein Native Fitness Potentials
Faraggi, Eshel; Kloczkowski, Andrzej
2013-03-01
Protein structure prediction can be separated into two tasks: sample the configuration space of the protein chain, and assign a fitness between these hypothetical models and the native structure of the protein. One of the more promising developments in this area is that of knowledge based energy functions. However, standard approaches using pair-wise interactions have shown shortcomings demonstrated by the superiority of multi-body-potentials. These shortcomings are due to residue pair-wise interaction being dependent on other residues along the chain. We developed a method that uses whole protein information filtered through machine learners to score protein models based on their likeness to native structures. For all models we calculated parameters associated with the distance to the solvent and with distances between residues. These parameters, in addition to energy estimates obtained by using a four-body-potential, DFIRE, and RWPlus were used as training for machine learners to predict the fitness of the models. Testing on CASP 9 targets showed that our method is superior to DFIRE, RWPlus, and the four-body potential, which are considered standards in the field.
Biological Potential in Serpentinizing Systems
Hoehler, Tori M.
2016-01-01
Generation of the microbial substrate hydrogen during serpentinization, the aqueous alteration of ultramafic rocks, has focused interest on the potential of serpentinizing systems to support biological communities or even the origin of life. However the process also generates considerable alkalinity, a challenge to life, and both pH and hydrogen concentrations vary widely across natural systems as a result of different host rock and fluid composition and differing physical and hydrogeologic conditions. Biological potential is expected to vary in concert. We examined the impact of such variability on the bioenergetics of an example metabolism, methanogenesis, using a cell-scale reactive transport model to compare rates of metabolic energy generation as a function of physicochemical environment. Potential rates vary over more than 5 orders of magnitude, including bioenergetically non-viable conditions, across the range of naturally occurring conditions. In parallel, we assayed rates of hydrogen metabolism in wells associated with the actively serpentinizing Coast Range Ophiolite, which includes conditions more alkaline and considerably less reducing than is typical of serpentinizing systems. Hydrogen metabolism is observed at pH approaching 12 but, consistent with the model predictions, biological methanogenesis is not observed.
Streaming potential of superhydrophobic microchannels.
Park, Hung Mok; Kim, Damoa; Kim, Se Young
2017-03-01
For the purpose of gaining larger streaming potential, it has been suggested to employ superhydrophobic microchannels with a large velocity slip. There are two kinds of superhydrophobic surfaces, one having a smooth wall with a large Navier slip coefficient caused by the hydrophobicity of the wall material, and the other having a periodic array of no- shear slots of air pockets embedded in a nonslip wall. The electrokinetic flows over these two superhydrophobic surfaces are modelled using the Navier-Stokes equation and convection-diffusion equations of the ionic species. The Navier slip coefficient of the first kind surfaces and the no-shear slot ratio of the second kind surfaces are similar in the sense that the volumetric flow rate increases as these parameter values increase. However, although the streaming potential increases monotonically with respect to the Navier slip coefficient, it reaches a maximum and afterward decreases as the no-shear ratio increases. The results of the present investigation imply that the characterization of superhydrophobic surfaces employing only the measurement of volumetric flow rate against pressure drop is not appropriate and the fine structure of the superhydrophobic surfaces must be verified before predicting the streaming potential and electrokinetic flows accurately. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Natural gas potential in Canada
International Nuclear Information System (INIS)
1997-01-01
An independent assessment of the undiscovered gas potential in Canada was conducted by a group of volunteer geoscientists. This report is the first of a series of assessments that are planned to be issued every three to four years. Separate assessments were made of conventional gas resources, unconventional gas resources and frontier gas resources. The assessment for conventional gas resources was organized into three categories: (1) gas producing areas where new discoveries can be integrated into existing producing and transportation infrastructure, (2) frontier basins where gas discoveries have been made, but no production is currently underway, and (3) frontier areas where gas-containing sedimentary rocks are known to exist, but where no gas discoveries have been made to date. The committee used year-end 1993 reserves data from discovered pools in each exploration play to predict the undiscovered potential. Information about discovered pools, geological setting, geographic limits and pool sizes of undiscovered pools in each exploration play was provided. Results of the investigation led to the conclusion that the natural gas potential in Canada is in fact larger than hitherto expected. It was estimated that in the Western Canada Sedimentary Basin 47 per cent of the total volume of conventional gas is yet to be discovered. 152 figs
Worldwide potential of wind energy
Energy Technology Data Exchange (ETDEWEB)
Flavin, C
1982-01-01
A well-documented discussion is presented dealing with the worldwide potential of wind energy as a source of electrical and mechanical power. It is pointed out that 2% of the solar insolation is converted to wind kinetic energy; it is constantly renewed and nondepletable. Efficiency of windmills are discussed (20 to 40%) and payback periods of less than 5 years are cited. Effects of wind velocity and site location are described. Wind pumps are reviewed and the need for wind pumps, particularly in the developing countries is stressed. The generation of electricity by windmills using small turbines is reviewed and appears promising in areas with wind velocities greater than 12 mi/hr. The development of large windmills and groups of windmills (windfarms) for large scale electrical power is discussed, illustrated, and reviewed (offshore sites included). Environmental and safety problems are considered as well as the role of electrical utilities, government support and research activities. It is concluded that the potential contribution of wind energy is immense and that mechanical windmills may become one of the most important renewable technologies. Electrical generating potential is estimated at 20 to 30% of electrical needs. International programs are discussed briefly. 57 references. (MJJ)
Energy intensities: Prospects and potential
International Nuclear Information System (INIS)
Anon.
1992-01-01
In the previous chapter, the author described how rising activity levels and structural change are pushing toward higher energy use in many sectors and regions, especially in the developing countries. The extent to which more activity leads to greater energy use will depend on the energy intensity of end-use activities. In this chapter, the author presents an overview of the potential for intensity reductions in each sector over the next 10-20 years. It is not the author's intent to describe in detail the various technologies that could be employed to improve energy efficiency, which has been done by others (see, for example, Lovins ampersand Lovins, 1991; Goldembert et al., 1987). Rather, he discusses the key factors that will shape future energy intensities in different parts of the world, and gives a sense for the changes that could be attained if greater attention were given to accelerate efficiency improvement. The prospects for energy intensities, and the potential for reduction, vary among sectors and parts of the world. In the majority of cases, intensities are tending to decline as new equipment and facilities come into use and improvements are made on existing stocks. The effect of stock turnover will be especially strong in the developing countries, where stocks are growing at a rapid pace, and the Former East Bloc, where much of the existing industrial plant will eventually be retired and replaced with more modern facilities. While reductions in energy intensity are likely in most areas, there is a large divergence between the technical and economic potential for reducing energy intensities and the direction in which present trends are moving. In the next chapter, the author presents scenarios that illustrate where trends are pointing, and what could be achieved if improving energy efficiency were a focus of public policies. 53 refs., 4 figs., 2 tabs
Cosmology and the Sinusoidal Potential
Bartlett, David F.
2006-06-01
The nature of dark matter (and dark energy) remains a mystery. An alternative is being explored by several scientists: changing Newton's (and Einstein's) field equations. The sinusoidal potential is the latest attempt[1]. Here the gravitational law is alternately attractive and repulsive:φ = -GM cos(kor)/r, where λo=2π/ko = 1/20 of the distance from the sun to the center of the Milky Way. The proposal accommodates several structural features of the Milky Way including, paradoxically, its spiral shape and flat rotation curve. The sinusoidal potential's unique feature is strong galactic tidal forces (dg/dr). These may explain why the new planetoid Sedna is securely between the Kuiper Belt and the Oort cloud and why distant comets are more influenced by galactic tides that are in the r, rather than the z-direction.At this meeting I discuss the consequences of the sinusoidal potential for cosmology. Here the alternation of attraction and repulsion gives (i) an open universe, and (ii) gravitational lensing which is usually weak, but occasionally very strong. An open universe is one that, asymptotically, has a size R which varies directly as time t. The open universe conflicts both with the old Einstein-deSitter model (R α t2/3} and the new accelerating one. The evidence for an accelerating universe decisively rejects the Einstein-deSitter model. The rejection of an open (or empty) universe is less secure. This rejection is influenced by the different ways the groups studying the brightness of supernovae use the HST. Surprising additional inputs include neutrino masses, the equivalence principle, LSB galaxies, and "over-luminous" Sn1a. I thank Mostafa Jon Dadras and Patrick Motl for early help and John Cumalat for continual support. [1] D.F. Bartlett, "Analogies between electricity and gravity", Metrologia 41, S115-S124 (2004).
World potential of renewable energies
Energy Technology Data Exchange (ETDEWEB)
Dessus, B; Devin, B; Pharabod, F
1991-07-01
A comprehensive analysis, region by region, of the actually accessible renewable energies at a given horizon, is presented. The same methodology as the one employed to derive ``proven fossil energy reserves`` from ``energy resources`` is adopted, in which resources are defined by quantitative information on physical potential, while reserves take into account technical and economical accessibility. As renewable resources are fluctuating with time and are diluted in space and not readily transportable or storeable, it is necessary to consider the presence of populations or activities near enough to be able to profit by these diluted and volatile energies.
Ethnography: principles, practice and potential.
Draper, Jan
2015-05-06
Ethnography is a methodology that is gaining popularity in nursing and healthcare research. It is concerned with studying people in their cultural context and how their behaviour, either as individuals or as part of a group, is influenced by this cultural context. Ethnography is a form of social research and has much in common with other forms of qualitative enquiry. While classical ethnography was characteristically concerned with describing 'other' cultures, contemporary ethnography has focused on settings nearer to home. This article outlines some of the underlying principles and practice of ethnography, and its potential for nursing and healthcare practice.
The Ergogenic Potential of Arginine
Directory of Open Access Journals (Sweden)
La Bounty Paul M
2004-12-01
Full Text Available Abstract Arginine is a conditionally essential amino acid that is involved in protein synthesis, the detoxification of ammonia, and its conversion to glucose as well as being catabolized to produce energy. In addition to these physiological functions, arginine has been purported to have ergogenic potential. Athletes have taken arginine for three main reasons: 1 its role in the secretion of endogenous growth hormone; 2 its involvement in the synthesis of creatine; 3 its role in augmenting nitric oxide. These aspects of arginine supplementation will be discussed as well as a review of clinical investigations involving exercise performance and arginine ingestion.
Analgesic Potential of Essential Oils
Directory of Open Access Journals (Sweden)
José Ferreira Sarmento-Neto
2015-12-01
Full Text Available Pain is an unpleasant sensation associated with a wide range of injuries and diseases, and affects approximately 20% of adults in the world. The discovery of new and more effective drugs that can relieve pain is an important research goal in both the pharmaceutical industry and academia. This review describes studies involving antinociceptive activity of essential oils from 31 plant species. Botanical aspects of aromatic plants, mechanisms of action in pain models and chemical composition profiles of the essential oils are discussed. The data obtained in these studies demonstrate the analgesic potential of this group of natural products for therapeutic purposes.
Proprioceptive evoked potentials in man
DEFF Research Database (Denmark)
Arnfred, S; Chen, A C; Eder, Derek N
2000-01-01
We studied cerebral evoked potentials on the scalp to the stimulation of the right hand from a change in weight of 400-480 g in ten subjects. Rise-time was 20g/10 ms, Inter Stimulus Interval 2s and stimulus duration was 100 ms. The cerebral activations were a double positive contralateral C3'/P70......). Further studies of the PEP are needed to assess the influence of load manipulations and of muscle contraction and to explore the effect of attentional manipulation....
Potential Psychiatric Uses for MDMA.
Yazar-Klosinski, B B; Mithoefer, M C
2017-02-01
Phase II trials of 3,4-methylenedioxymethamphetamine (MDMA)-assisted psychotherapy have demonstrated initial safety and efficacy for treatment of posttraumatic stress disorder (PTSD), with potential for expansion to depression and anxiety disorders. In these trials, single doses of MDMA are administered in a model of medication-assisted psychotherapy, differing from trials involving daily drug administration without psychotherapy. This model presents an opportunity to utilize accelerated regulatory pathways, such as the US Food and Drug Administration (FDA) Breakthrough Therapy Designation, to most effectively and expeditiously test such novel approaches. © 2016, The Authors. Clinical Pharmacology & Therapeutics published by Wiley Periodicals, Inc. on behalf of American Society for Clinical Pharmacology and Therapeutics.
Calculation of Rydberg interaction potentials
DEFF Research Database (Denmark)
Weber, Sebastian; Tresp, Christoph; Menke, Henri
2017-01-01
for calculating the required electric multipole moments and the inclusion of electromagnetic fields with arbitrary direction. We focus specifically on symmetry arguments and selection rules, which greatly reduce the size of the Hamiltonian matrix, enabling the direct diagonalization of the Hamiltonian up...... to higher multipole orders on a desktop computer. Finally, we present example calculations showing the relevance of the full interaction calculation to current experiments. Our software for calculating Rydberg potentials including all features discussed in this tutorial is available as open source....
Theory of complex potential scattering
International Nuclear Information System (INIS)
Kok, L.P.; Haeringen, H.v.
1981-01-01
We study the effect of the addition of a complex potential lambdaV/sub sep/ to an arbitrary Schroedinger operator H = H 0 +V on the singularities of the S matrix, as a function of lambda. Here V/sub sep/ is a separable interaction, and lambda is a complex coupling parameter. The paths of these singularities are determined to a great extent by certain saddle points in the momentum (or energy) plane. We explain certain critical phenomena recently reported in the literature. Associated with these saddles are branch-type singularities in the complex lambda plane, which are dynamical in origin. Some examples are discussed in detail
Nanothermodynamics: a subdivision potential approach
Directory of Open Access Journals (Sweden)
R. Moussavi
2005-12-01
Full Text Available Classical thermodynamic laws and relations have been developed for macroscopic systems that satisfy the thermodynamic limit. These relations are challenged as the system size decreases to the scale of nano-systems, in which thermodynamic properties are overshadowed by system size, and the usual classical concepts of extensivity and intensivity are no longer valid. The challenges to the classical thermodynamics in relation to small systems are demonstrated, and via the approach introduced by Hill, the concept of sub-division potential is clarified in details. The fundamental thermodynamic relations are obtained using a rational-based method.
Potential benefits from the CTBT
International Nuclear Information System (INIS)
Chang, H.L.
1999-01-01
Discussing the potential benefits from the CTBT monitoring in Africa, analysis and data communication systems it was concluded that although yet undeveloped, the possibilities arising from participation in CTBT regime are being identified. The integrated data obtained from the verification technologies of the CTBT should open further horizons for civil society. The main topics of interest are: treaty related science and technology developments, monitoring techniques, ideas and initiatives for expanding existing activities and developing cooperation, including the issues of regional centres and centres of excellence
The effective crystal field potential
Mulak, J
2000-01-01
As it results from the very nature of things, the spherical symmetry of the surrounding of a site in a crystal lattice or an atom in a molecule can never occur. Therefore, the eigenfunctions and eigenvalues of any bound ion or atom have to differ from those of spherically symmetric respective free ions. In this way, the most simplified concept of the crystal field effect or ligand field effect in the case of individual molecules can be introduced. The conventional notion of the crystal field potential is narrowed to its non-spherical part only through ignoring the dominating spherical part which produces only a uniform energy shift of gravity centres of the free ion terms. It is well understood that the non-spherical part of the effective potential "seen" by open-shell electrons localized on a metal ion plays an essential role in most observed properties. Light adsorption, electron paramagnetic resonance, inelastic neutron scattering and basic characteristics derived from magnetic and thermal measurements, ar...
Calculation of Rydberg interaction potentials
International Nuclear Information System (INIS)
Weber, Sebastian; Büchler, Hans Peter; Tresp, Christoph; Urvoy, Alban; Hofferberth, Sebastian; Menke, Henri; Firstenberg, Ofer
2017-01-01
The strong interaction between individual Rydberg atoms provides a powerful tool exploited in an ever-growing range of applications in quantum information science, quantum simulation and ultracold chemistry. One hallmark of the Rydberg interaction is that both its strength and angular dependence can be fine-tuned with great flexibility by choosing appropriate Rydberg states and applying external electric and magnetic fields. More and more experiments are probing this interaction at short atomic distances or with such high precision that perturbative calculations as well as restrictions to the leading dipole–dipole interaction term are no longer sufficient. In this tutorial, we review all relevant aspects of the full calculation of Rydberg interaction potentials. We discuss the derivation of the interaction Hamiltonian from the electrostatic multipole expansion, numerical and analytical methods for calculating the required electric multipole moments and the inclusion of electromagnetic fields with arbitrary direction. We focus specifically on symmetry arguments and selection rules, which greatly reduce the size of the Hamiltonian matrix, enabling the direct diagonalization of the Hamiltonian up to higher multipole orders on a desktop computer. Finally, we present example calculations showing the relevance of the full interaction calculation to current experiments. Our software for calculating Rydberg potentials including all features discussed in this tutorial is available as open source. (tutorial)
Potential energy center site investigations
International Nuclear Information System (INIS)
Savage, W.F.
1977-01-01
Past studies by the AEC, NRC, NSF and others have indicated that energy centers have certain advantages over dispersed siting. There is the need, however, to investigate such areas as possible weather modifications due to major heat releases, possible changes in Federal/state/local laws and institutional arrangements to facilitate implementation of energy centers, and to assess methods of easing social and economic pressures on a surrounding community due to center construction. All of these areas are under study by ERDA, but there remains the major requirement for the study of a potential site to yield a true assessment of the energy center concept. In this regard the Division of Nuclear Research and Applications of ERDA is supporting studies by the Southern and Western Interstate Nuclear Boards to establish state and utility interest in the concept and to carry out screening studies of possible sites. After selection of a final site for center study , an analysis will be made of the center including technical areas such as heat dissipation methods, water resource management, transmission methods, construction methods and schedules, co-located fuel cycle facilities, possible mix of reactor types, etc. Additionally, studies of safeguards, the interaction of all effected entities in the siting, construction, licensing and regulation of a center, labor force considerations in terms of local impact, social and economic changes, and financing of a center will be conducted. It is estimated that the potential site study will require approximately two years
Safety assessments for potential exposures
International Nuclear Information System (INIS)
Dunn, D.I.
2012-04-01
Safety Assessment of potential exposures have been carried out in major practices, namely: industrial radiography, gamma irradiators and electron accelerators used in industry and research, and radiotherapy. This paper focuses on reviewing safety assessment methodologies and using developed software to analyse radiological accidents, also review, and discuss these past accidents.The primary objective of the assessment is to assess the adequacy of planned or existing measures for protection and safety and to identify any additional measures that should be put in place. As such, both routine use of the source and the probability and magnitude of potential exposures arising from accidents or incidents should be considered. Where the assessment indicates that there is a realistic possibility of an accident affecting workers or members of the public or having consequences for the environment, the registrant or licensee should prepare a suitable emergency plan. A safety assessment for normal operation addresses all the conditions under which the radiation source operates as expected, including all phases of the lifetime of the source. Due account needs to be taken of the different factors and conditions that will apply during non-operational phases, such as installation, commissioning and maintenance. (author)
Convexity of the effective potential
International Nuclear Information System (INIS)
Haymaker, R.W.; Perez-Mercader, J.
1978-01-01
The effective potential V(phi) in field theories is a convex function of phi. V(lambda phi 1 + (1 - lambda)phi 2 ) less than or equal to lambdaV(phi 1 ) + (1 - lambda)V(phi 2 ), 0 less than or equal to lambda less than or equal to 1, all phi 1 , phi 2 . A linear interpolation of V(phi) is always larger than or equal to V(phi). There are numerous examples in the tree approximation and in perturbation theory for which this is not the case, the most notorious example being the double dip potential. More complete solutions may or may not show this property automatically. However, a non-convex V(phi) simply indicates that an unstable vacuum state was used in implementing the definition of V(phi). A strict definition will instruct one to replace V(phi) with its linear interpolation in such a way as to make it convex. (Alternatively one can just as well take the view that V(phi) is undefined in these domains.) In this note, attention is called to a very simple argument for convexity based on a construction described by H. Callen in his classic book Thermodynamics
Potential hazards of diagnostic radiation
Energy Technology Data Exchange (ETDEWEB)
Houston, C S; Shokeir, M H
1977-03-01
There are no precise data for determining the extent of somatic damage from small doses of radiation used in diagnostic radiology. Diagnostic radiation given to pregnant women, knowingly or unknowingly, should rarely reach teratogenic levels causing brain and eye abnormalities. Evidence suggests that it does increase the risk of childhood malignancy, especially leukemia. Although rapidly growing tissues seem most susceptible, all radiation probably carries a very small risk of carcinogenesis. Genetic damage is equally difficult to estimate. Diagnostic radiation of females, even in childhood, may be related to an increased incidence of Down's syndrome in older mothers. Radiation also causes point mutations, which may explain the increase of some genetic abnormalities in progeny of older fathers. Whenever an abdominal or pelvic radiograph is ordered before the end of the reproductive period, there must be a potential benefit to balance the small risk involved.
The potential of renewable energies
International Nuclear Information System (INIS)
Glubrecht, H.
1998-01-01
If one compares the progress in research and development of renewable energy applications with the finding which has been granted to these activities during the 23 years after the first oil shock, one cannot but be very impressed. It is indicated in this paper hoe comprehensive the potential of renewable energy is. One should take into account that the methods described form a broad interdisciplinary field in contrast to fossil and nuclear technologies. From technical point of view the present and future energy demand can be met by the broad spectrum of renewable energies in combination with energy conservation. Many of these techniques are already economically competitive: solar architecture, wind energy, hydropower, low temperature heat production, photovoltaic for remote areas, various types of biomass application, geothermal energy although not exactly renewable. The future of renewable energies will depend on opening markets for these techniques
Sustainability Potentials of Housing Refurbishment
Directory of Open Access Journals (Sweden)
Behzad Sodagar
2013-03-01
Full Text Available The benefits of choosing refurbishment over new build have recently been brought into focus for reducing environmental impacts of buildings. This is due to the fact that the existing buildings will comprise the majority of the total building stocks for years to come and hence will remain responsible for the majority of greenhouse gas emissions from the sector. This paper investigates the total potentials of sustainable refurbishment and conversion of the existing buildings by adopting a holistic approach to sustainability. Life Cycle Assessment (LCA and questionnaires have been used to analyse the environmental impact savings (Co2e, improved health and well-being, and satisfaction of people living in refurbished homes. The results reported in the paper are based on a two year externally funded research project completed in January 2013.
Potential risks of nuclear ships
International Nuclear Information System (INIS)
Oelgaard, P.L.
1994-07-01
This report represents an attempt to evaluate the potential risks of nuclear ships. Firstly reasons are given why nuclear ship accidents will not lead to accidents of the magnitude of the Chernobyl accident. This is due to much lower content of radioactive material and to different reactor designs. Next a review is given of the types of accidents which have actually occurred. Of these the reactor accidents which may lead to serious consequences for the crew and the environment are considered further. These are reactivity accidents and loss of coolant accidents. In addition the long term risks of sunken nuclear ships and sea disposed reactor compartments etc. are also discussed. Based on available accident data an attempt is made to estimate the probability of serious nuclear ship accidents. (au)
Introduction: Translating Potential into Profits
DEFF Research Database (Denmark)
Lubinski, Christina; Kipping, Matthias
2015-01-01
potential into profits.’ The history of multinational enterprises (MNEs) knows many examples of economies with these characteristics similar to modern understandings of ‘emerging markets.’ This special issue analyzes foreign multinationals in emerging markets from a historical perspective. It seeks...... to understand changes and continuities in the opportunities and challenges less developed markets presented for MNEs, and in the various ways in which their managers responded to these. Rather than relying on the ‘emerging market’ label, we ask (1) why managers perceived certain markets as ‘emerging’ and which...... expectations they had when investing in these markets, (2) which challenges they faced there, and (3) how they subsequently addressed them. By tracing and comparing these investments and their consequences over time (and space), we hope to shed more light on managerial decisions and understand to what extent...
Potentialities of Revised Quantum Electrodynamics
Directory of Open Access Journals (Sweden)
Lehnert B.
2013-10-01
Full Text Available The potentialities of a revised quantum electrodynamic theory (RQED earlier established by the author are reconsidered, also in respect to other fundamental theories such as those by Dirac and Higgs. The RQED theory is characterized by intrinsic linear symmetry breaking due to a nonzero divergence of the electric field strength in the vacuum state, as supported by the Zero Point Energy and the experimentally confirmed Casimir force. It includes the results of electron spin and antimatter by Dirac, as well as the rest mass of elementary particles predicted by Higgs in terms of spontaneous nonlinear symmetry breaking. It will here be put into doubt whether the approach by Higgs is the only theory which becomes necessary for explaining the particle rest masses. In addition, RQED theory leads to new results beyond those being available from the theories by Dirac, Higgs and the Standard Model, such as in applications to leptons and the photon.
Antidiabetic potential of Conocarpus lancifolius
Directory of Open Access Journals (Sweden)
Malik Saadullah
2014-06-01
Full Text Available The antidiabetic activity of Conocarpus lancifolius extract was investigated in vitro, as alpha glucosidase inhibition and in vivo as alloxan induced diabetic rabbits with other biochemical parameters (LDL, HDL, SGPT, SGOT, cretinine, urea and triglyceride. Alpha-glucosidase inhibition activity was performed by using acorbose as standred. Methanolic extract show alpha-glucosidase inhibition activity. The dose of 200 mg/kg body weight significantly (p<0.05 decreases the blood glucose level, plasma total cholesterol, triglycerides and LDL in treated rabbits as compared to diabetic rabbits. This dose significantly increased the level of HDL in treated group. The activity of SGOT and SGPT also significantly (p<0.05 decreased in treated diabetic rabbits. Phytochemical studies show the presence of glycosides, tannins, saponins and terpenoids. The antidiabetic potential is may be due to its saponin contents.
Prediction of acid generation potential
International Nuclear Information System (INIS)
Nalbandyan, V.B.
1992-01-01
This paper discusses acid rock drainage (ARD), a term used to describe leachate, seepage, or drainage that has been affected by the natural oxidation of sulfide minerals contained in rock which is exposed to air and water. The principal ingredients for ARD formation are reactive sulfide minerals, oxygen, and water. The oxidation reactions responsible for the formation of ARD are often accelerated by biological activity. These reactions yield low pH (acidic) water that has the potential to mobilize heavy metals that may be contained in the geologic materials that are contacted. ARD can cause a detrimental impact on the quality of ground or surface water to which it discharges. ARD likely has been associated with mines since mining began. ARD is not necessarily confined to mining activities, but can occur naturally wherever sulfide-bearing rock is exposed to air and water. It is important to recognize that not all operations that expose sulfide-bearing rock will result in ARD
Energy Technology Data Exchange (ETDEWEB)
1992-01-01
Summaries of papers presented at the European wind energy conference on the potential of wind farms are presented. It is stated that in Denmark today, wind energy provides about 3% to the Danish electricity consumption and the wind power capacity is, according to Danish wind energy policy, expected to increase substantially in the years to come. A number of countries in Europe and elsewhere are making significant progress in this repect. Descriptions of performance are given in relation to some individual wind farms. The subjects covered concern surveys of national planning and policies regarding wind utilization and national and global development of wind turbine arrays. Papers also deal with utility and project planning, wind prediction and certification, wind loads and fatigue, wakes, noise and control. (AB).
Unleashing the Potential of SCM
DEFF Research Database (Denmark)
Møller, Charles
2005-01-01
This paper argues that with the present state of Enterprise Resource Planning (ERP) adoption by the companies, the potential benefits of Supply Chain Management (SCM) and integration is about to be unleashed. This paper presents the results and the implications of a survey on ERP adoption...... in the 500 largest Danish enterprises. The study is based on telephone interviews with ERP managers in 88.4 % of the "top 500" enterprises in Denmark. Based on the survey, the paper suggests the following four propositions: (i) ERP has become the pervasive infrastructure; (ii) ERP has become a contemporary...... technology; (iii) ERP adoption has matured; and (iv) ERP adoption is converging towards a dominant design. Finally, the paper discusses the general implications of the surveyed state of practice on the SCM research challenges. Consequently we argue that research needs to adjust its conceptions of the ERP...
Characteristics of potential repository wastes
International Nuclear Information System (INIS)
Cowart, C.G.; Notz, K.J.
1992-10-01
This report presents the results of a fully documented peer review of DOE/RW-0184, Rev. 1, ''Characteristics of Potential Repository Wastes''. The peer review was chaired and administered by oak Ridge National Laboratory (ORNL) for the Department of Energy (DOE), Office of Civilian Radioactive Waste Management (OCRWM) and was conducted in accordance with OCRWM QA procedure QAAP 3.3 ''Peer Review'' for the purpose of quailing the document for use in OCRWM quality-affecting work. The peer reviewers selected represent a wide range of experience and knowledge particularly suitable for evaluating the subject matter. A total of 596 formal comments were documented by the seven peer review panels, and all were successfully resolved. The peers reached the conclusion that DOE/RW-0184, Rev. 1, is quality determined and suitable for use in quality-affecting work
Status of effective potential calculations
Quiros, M.
1995-01-01
We review various effective potential methods which have been useful to compute the Higgs mass spectrum and couplings of the minimal supersymmetric standard model. We compare results where all-loop next-to-leading-log corrections are resummed by the renormalization group, with those where just the leading-log corrections are kept. Pole masses are obtained from running masses by addition of convenient self-energy diagrams. Approximate analytical expressions are worked out, providing an excellent approximation to the numerical results which include all next-to-leading-log terms. An appropriate treatment of squark decoupling allows to consider large values of the stop and/or sbottom mixing parameters and thus fix a reliable upper bound on the mass of the lightest CP-even Higgs boson mass.
"Human potential" and progressive pedagogy
DEFF Research Database (Denmark)
Øland, Trine
2012-01-01
This article examines the cultural constructs of progressive pedagogy in Danish school pedagogy and its emerging focus on the child’s human potential from the 1920s to the 1950s. It draws on Foucault’s notion of ‘dispositifs’ and the ‘elements of history’, encircling a complex transformation......: the emergence of ‘intelligence’ and life as a biological phenomenon from the 1920s is illustrated; the emergence of ‘Black culture’, ‘Negros’ and ‘races’ from the 1930s is depicted, and the emergence of ‘national cultures’ from the 1940s – enhanced by UNESCO after World War II – is demonstrated. Although race...
Corrected body surface potential mapping.
Krenzke, Gerhard; Kindt, Carsten; Hetzer, Roland
2007-02-01
In the method for body surface potential mapping described here, the influence of thorax shape on measured ECG values is corrected. The distances of the ECG electrodes from the electrical heart midpoint are determined using a special device for ECG recording. These distances are used to correct the ECG values as if they had been measured on the surface of a sphere with a radius of 10 cm with its midpoint localized at the electrical heart midpoint. The equipotential lines of the electrical heart field are represented on the virtual surface of such a sphere. It is demonstrated that the character of a dipole field is better represented if the influence of the thorax shape is reduced. The site of the virtual reference electrode is also important for the dipole character of the representation of the electrical heart field.
The potential of the internet.
Coleman, Jamie J; McDowell, Sarah E
2012-06-01
The internet and the World Wide Web have changed the ways that we function. As technologies grow and adapt, there is a huge potential for the internet to affect drug research and development, as well as many other aspects of clinical pharmacology. We review some of the areas of interest to date and discuss some of the potential areas in which internet-based technology can be exploited. Information retrieval from the web by health-care professionals is common, and bringing evidence-based medicine to the bedside affects the care of patients. As a primary research tool the web can provide a vast array of information in generating new ideas or exploring previous research findings. This has facilitated systematic reviewing, for example. The content of the web has become a subject of research in its own right. The web is also widely used as a research facilitator, including enhancement of communication between collaborators, provision of online research tools (such as questionnaires, management of large scale multicentre trials, registration of clinical trials) and distribution of information. Problems include information overload, ignorance of early data that are not indexed in databases, difficulties in keeping web sites up to date and assessing the validity of information retrieved. Some web-based activities are viewed with suspicion, including analysis by pharmaceutical companies of drug information to facilitate direct-to-consumer advertising of novel pharmaceuticals. Use of these technologies will continue to expand in often unexpected ways. Clinical pharmacologists must embrace internet technology and include it as a key priority in their research agenda. © 2012 The Authors. British Journal of Clinical Pharmacology © 2012 The British Pharmacological Society.
Smallholder telecoupling and potential sustainability
Directory of Open Access Journals (Sweden)
Karl S. Zimmerer
2018-03-01
Full Text Available Smallholders are crucial for global sustainability given their importance to food and nutritional security, agriculture, and biodiversity conservation. Worldwide smallholders are subject to expanded telecoupling whereby their social-ecological systems are linked to large-scale socioeconomic and environmental drivers. The present research uses the synthesis of empirical evidence to demonstrate smallholder telecoupling through the linkages stemming from the global-level integration of markets (commodity, labor, finance, urbanization, governance, and technology. These telecoupling forces are often disadvantageous to smallholders while certain conditions can contribute to the potential sustainability of their social-ecological systems. Case studies were chosen to describe sustainability opportunities and limits involving smallholder production and consumption of high-agrobiodiversity Andean maize amid telecoupled migration (Bolivia, the role of international eco-certification in smallholder coffee-growing and agroforests (Colombia, smallholder organic dairy production in large-scale markets and technology transfer (upper Midwest, U.S.A., and smallholders' global niche commodity production of argan oil (Morocco. These case studies are used to identify the key challenges and opportunities faced by smallholders in telecoupling and to develop a conceptual framework. This framework specifies the integrated roles of global systems together with influential public and private institutions operating at multiple scales including the national level. The framework also integrates the local dynamics of smallholders' multiple land use units and their socioeconomic and environmental variation. Spatial spillover effects in smallholder landscapes are an additional element. This framework further establishes the un-Romantic, nonteleological, and antifetishistic view of smallholders. It provides specific insights on the multilevel dynamics of smallholder telecoupling
The phenomenon of retarded potentials
International Nuclear Information System (INIS)
Noskov, N.K.
2003-01-01
The logic simulation of process of time delay of potential on a moved body - recipient resulted in the deduction about cyclic irregularity of time delay, that means, that the moved body makes longitudinal vibrations. A conclusion is drawn that length of longitudinal vibrations depending from three variable: the law of interaction, spacing interval between bodies of interaction and phase velocity looks like: λ=Hv ph /R·F(R) (1), where λ- length of oscillations; H- factor of proportionality; v ph - phase velocity of a body; R - distance between test and central bodies R(t); F(R) - law of interaction. So far as λ=v ph /v, and R·F(R)=∫ ∞ R F(R)dR=E move , then formula (1) will be transformed into: E move =Hv pv /λ=Hv. Thus, the energy of radiating having the similar law is only reflex of motion of a matter. The energy of oscillating motion can be expressed through linear maximal velocity. It is established, that different expressions of the same energy, result in the law of a view of a proportion for lengths of de Broglie's waves: It shows that de Broglie's waves - the actual oscillating motions of bodies, as demonstrate interference and diffraction pictures at a dissipation of the accelerated particles on crystalline gratings. This deduction has far-reaching consequences for finding - out of the cause bases of the laws of a nature. So, the quantum mechanics becomes partition of mechanics of solids and is comprises all interactions. The nuclear energy is not 'defect of mass', but is 'defect' of energy of oscillating motion: ΔE=H v1 -H v2 . Definition of real cause of nuclear energy is very important for construction of model of nuclei and for development of physics as the whole. The interconnection of the phenomenon of longitudinal vibrations of moved bodies, as result of irregularity of time delay of potential, with many other natural phenomena is looked through. By such, as: motion of planets and electrons on elliptical orbits, oscillating of dipping drips
The potential of renewable energy
Energy Technology Data Exchange (ETDEWEB)
1990-03-01
On June 27 and 28, 1989, the US Department of Energy (DOE) national laboratories were convened to discuss plans for the development of a National Energy Strategy (NES) and, in particular, the analytic needs in support of NES that could be addressed by the laboratories. As a result of that meeting, interlaboratory teams were formed to produce analytic white papers on key topics, and a lead laboratory was designated for each core laboratory team. The broad-ranging renewables assignment is summarized by the following issue statement from the Office of Policy, Planning and Analysis: to what extent can renewable energy technologies contribute to diversifying sources of energy supply What are the major barriers to greater renewable energy use and what is the potential timing of widespread commercialization for various categories of applications This report presents the results of the intensive activity initiated by the June 1989 meeting to produce a white paper on renewable energy. Scores of scientists, analysts, and engineers in the five core laboratories gave generously of their time over the past eight months to produce this document. Their generous, constructive efforts are hereby gratefully acknowledged. 126 refs., 44 figs., 32 tabs.
The biomethane potential in Chile
International Nuclear Information System (INIS)
Seiffert, M.; Kaltschmitt, M.; Miranda, J.A.
2009-01-01
Within the last decade natural gas gained considerable importance in Chile. The contribution of natural gas within the energy system will increase in the future by predicted 3.6% annually until the year 2015. Due to limited resources within its own country, the energy system of Chile depends on natural gas imports preferential from Argentina. Therefore, the aim of several stakeholders from policy and industry is to reduce the share of imported primary energy within the overall energy system. In order to reach this goal, the use of domestic resources and particularly the utilisation of biomass as one of the most important renewable sources of energy in Chile could play an important role. Against this background, the goal of this paper is the analysis of the technical potentials of biomethane as a substitute for natural gas. For the production of biomethane the anaerobic or bio-chemical (i.e. Biogas) as well as the thermo-chemical conversion pathways (i.e. Bio-SNG) are considered. The results of this analysis show that biomass converted to biomethane is a promising energy provision option for Chile and it contributes to the reduction of greenhouse gas emissions
The Tectonic Potentials of Concrete
DEFF Research Database (Denmark)
Egholm Pedersen, Ole
2013-01-01
Contemporary techniques for concrete casting in an architectural context are challenged by demands of increased individualization in our built environment, reductions in the use of resources and waste generation. In recent years, new production technologies and strategies that break with the indu......Contemporary techniques for concrete casting in an architectural context are challenged by demands of increased individualization in our built environment, reductions in the use of resources and waste generation. In recent years, new production technologies and strategies that break...... with the industrial paradigm of standardization, have been put forward. This development is carried forward by computers and digital fabrication, but has yet to find its way into the production of building components. With regards to concrete casting, however, existing research do offer advancement towards...... an increased customisation of casting moulds. The hypothesis of this research is that the techniques used in this research do not fully address the tectonic potentials of concrete which gives rise to the primary research question: Is it possible to enhance existing or develop new concrete casting techniques...
Ozone depletion potentials of halocarbons
International Nuclear Information System (INIS)
Karol, I.L.; Kiselev, A.A.
1992-01-01
The concept of ozone depletion potential (ODP) is widely used in the evaluation of numerous halocarbons and of their replacements for effects on ozone, but the methods, model assumptions and conditions of ODP calculation have not been analyzed adequately. In this paper, a model study of effects on ozone after the instantaneous releases of various amounts of CH 3 CCl 3 and of CHF 2 Cl(HCFC-22) in the several conditions of the background atmosphere are presented, aimed to understand the main connections of ODP values with the methods of their calculations. To facilitate the ODP computation in numerous versions for long after the releases, the above rather short-lived gases have been used. The variation of released gas global mass from 1 Mt to 1 Gt leads to ODP value increase atmosphere. The same variations are analyzed for the CFC-free atmosphere of 1960s conditions for the anthropogenically loaded atmosphere in the 21st century according to the known IPCC- A scenario (business as usual). Recommendations of proper ways of ODP calculations are proposed for practically important cases
Job creation potential of solar
International Nuclear Information System (INIS)
McMonagle, R.
2005-01-01
This document defines the size of the job market within Canada's solar industry and presents a preliminary forecast of the employment opportunities through to 2025. The issue of job potential within Canada's solar technologies is complicated by the wide range of different fields and technologies within the solar industry. The largest energy generator of the solar technologies is passive solar, but the jobs in this sector are generally in the construction trades and window manufacturers. The Canadian Solar Industries Association estimates that there are about 360 to 500 firms in Canada with the primary business of solar technologies, employing between 900 to 1,200 employees. However, most solar manufacturing jobs in Canada are for products exports as demonstrated by the 5 main solar manufacturers in Canada who estimate that 50 to 95 per cent of their products are exported. The main reason for their high export ratio is the lack of a Canadian market for their products. The 3 categories of job classifications within the solar industry include manufacturing, installation, and operations and maintenance. The indirect jobs include photovoltaic system hardware, solar hot water heating, solar air ventilation, and glass/metal framing. 17 refs., 3 tabs., 2 figs
Characteristics of potential repository wastes
International Nuclear Information System (INIS)
Notz, K.J.
1989-01-01
The Office of Civilian Radioactive Waste Management (OCRWM) is responsible for the spent fuels and other wastes that will be disposed of in a geologic repository. The two major sources of these materials are commercial light-water reactor (LWR) spent fuel and immobilized high-level waste (HLW). Other wastes that may require long-term isolation include non-LWR spent fuels and miscellaneous sources such as activated metals. Detailed characterizations are required for all of these potential repository wastes. These characterizations include physical, chemical, and radiological properties. The latter must take into account decay as a function of time. This information has been extracted from primary data sources, evaluated, and assembled in a Characteristics Data Base which provides data in four formats: hard copy standard reports, menu-driven personal computer (PC) data bases, program-level PC data bases, and mainframe computer files. The Characteristics Data Base provides a standard set of self-consistent data to the various areas of responsibility including systems integration and waste stream analysis, storage, transportation, and geologic disposal. The data will be used for design studies, evaluation of alternatives, and system optimization by OCRWM and supporting contractors. 7 refs., 5 figs., 7 tabs
Galalctic Tides & the Sinusoidal Potential
Bartlett, David F.
2011-05-01
The sinusoidal potential is a nonNewtonian alternative to dark matter. Instead of φ = -GM/r we write φ = -(GM/r) cos kor, where ko= 2π/ λo and λo = Ro/20= 400 pc. Evidence for this choice for the "wavelength” λo has been given in one article and many previous meetings of the AAS & DDA. The solar system and nearby stars are trapped in a local groove of width Δr Quality (4 types) and semi-major axis aoriginal . For 10 of the 12 classes radial tides dominate Z-tides. The classic Oort cloud comets (1851-1996) have a particularly strong modulation with galactic longitude. This modulation is exactly in those directions where a radial tide would be important. The equally numerous recent Oort comets (1996-2008) show a different evidence for strong radial tides. The recent comets generally have much larger perihelion distances q than the classic ones. Here the evidence is that a radial tide is removing angular momentum from the orbit and thus bringing the perihelion closer to the earth and to observers.
Biological potential of Stillingia oppositifolia
Directory of Open Access Journals (Sweden)
Betania Barros Cota
2011-02-01
Full Text Available Organic extracts from leaves and stems of Stillingia oppositifolia Baill. ex Müll. Arg., Euphorbiaceae, were screened for antifungal and cytotoxic properties. The extracts presented Minimum Inhibitory Concentration values around 250 µg.mL-1 against Candida krusei and Candida tropicalis, and around 63 µg.mL-1 for Paracoccidioides brasiliensis. They were tested on three human cell lines (UACC-62, MCF-7, and TK-10, disclosing GI50 values, (concentration able to inhibit 50% of the cell growth ranging from 50 to 100 µg.mL-1. Organic extract from stems furnished hexanic, dichloromethanic and aqueous phases after partition. Chromatographic fractionation of the hexanic soluble phase of the stems yielded aleuritolic acid 3-acetate, β-sitosterol, 3-epi-β-amyrin, β-amyrone and palmitic acid. These compounds showed antifungal and cytotoxic activities in the same range as the organic crude extract and low toxic effect against mononuclear cells obtained from human peripheral blood. This is the first report on chemical and biological potential of S. oppositifolia.
Thermodynamic potential in quantum electrodynamics
International Nuclear Information System (INIS)
Morley, P.D.
1978-01-01
The thermodynamic potential, Ω, in quantum electrodynamics (QED) is derived using the path-integral formalism. Renormalization of Ω is shown by proving the following theorem: Ω/sub B/(e/sub B/,m/sub B/,T,μ) - Ω/sub B/(e/sub B/,m/sub B/,T = 0,μ = 0) = Ω/sub R/(e/sub R/,m/sub R/,T,μ,S), where B and R refer to bare and renormalized quantities, respectively, and S is the Euclidean subtraction momentum squared. This theorem is proved explicitly to e/sub R/ 4 order and could be analogously extended to any higher order. Renormalization-group equations are derived for Ω/sub R/, and it is shown that perturbation theory in a medium is governed by effective coupling constants which are functions of the density. The behavior of the theory at high densities is governed by the Euclidean ultraviolet behavior of the theory in the vacuum
The Analgesic Potential of Cannabinoids
Elikottil, Jaseena; Gupta, Pankaj; Gupta, Kalpna
2013-01-01
Historically and anecdotally cannabinoids have been used as analgesic agents. In recent years, there has been an escalating interest in developing cannabis-derived medications to treat severe pain. This review provides an overview of the history of cannabis use in medicine, cannabinoid signaling pathways, and current data from preclinical as well as clinical studies on using cannabinoids as potential analgesic agents. Clinical and experimental studies show that cannabis-derived compounds act as anti-emetic, appetite modulating and analgesic agents. However, the efficacy of individual products is variable and dependent upon the route of administration. Since opioids are the only therapy for severe pain, analgesic ability of cannabinoids may provide a much-needed alternative to opioids. Moreover, cannabinoids act synergistically with opioids and act as opioid sparing agents, allowing lower doses and fewer side effects from chronic opioid therapy. Thus, rational use of cannabis based medications deserves serious consideration to alleviate the suffering of patients due to severe pain. PMID:20073408
Photovoltaic energy potential of Quebec
International Nuclear Information System (INIS)
Royer, J.; Thomas, R.
1993-01-01
Results are presented from a study concerning the potential of photovoltaic (PV) energy in Quebec to the year 2010. The different PV applications which are or will be economically viable in Quebec for the study period are identified and evaluated in comparison with the conventional energy sources used for these applications. Two penetration scenarios are proposed. One considers little change at the level of policies established for commercialization of PV sources, and the other considers certain measures which accelerate the implementation of PV technology in certain niches. While the off-grid market is already motivated to adopt PV technology for economic reasons, it is forecast that all encouragement from lowering costs would accelerate PV sales, offering a larger purchasing power to all interested parties. Above all, lowered PV costs would open up the network market. Photovoltaics would have access to a much larger market, which will accelerate changes in the very nature of the industry and bring with it new reductions in the costs of producing PV systems. 5 refs., 1 fig., 7 tabs
Theoretical study on optical model potential
International Nuclear Information System (INIS)
Lim Hung Gi.
1984-08-01
The optical model potential of non-local effect on the rounded edge of the potential is derived. On the basis of this potential the functional form of the optical model potential, the energy dependence and relationship of its parameters, and the dependency of the values of the parameters on energy change are shown in this paper. (author)
Beautiful, but also potentially invasive
Directory of Open Access Journals (Sweden)
Lipták Boris
2015-03-01
Full Text Available Introduction of non-indigenous exotic species to new areas, where they may establish viable populations and become invasive, is a considerable problem in the protection of nature worldwide, as these species may alter the indigenous species population structure and potentially even decrease the biodiversity. The European fauna underwent through major negative changes on the continent and nowadays, it experiences another new treat, represented by the expanding aquarium pet trade, and with it, associated species (and disease introductions. Exotic freshwater crustaceans are one of the taxa widely incorporated in the business, counting a remarkable number of species. Recent records of the exotic marbled crayfish or Marmorkrebs (Procambarus fallax f. virginalis in German in open ecosystems in Slovakia pointed to human-mediated introductions associated with aquarium pet trade in the country. In this regard, a study of the aquarium pet trade both in expositions and shops and online was assessed. Several crustacean taxa are available both in pet trade exhibitions and online through the Internet. Altogether 26 different species were identified in the aquarium trade in Slovakia. These are Procambarus fallax f. virginalis, P. clarkii, P. alleni, Cherax quadricarinatus, C. destructor, C. holthuisi, C. peknyi, Cambarellus patzcuarensis and C. diminutus occurring in the aquarium pet trade in Slovakia (n = 9. Procambarus fallax f. virginalis, P. clarkii and C. patzuarensis are the most common in this regard. There is also a quantity of other related taxa in the aquarium pet trade in Slovakia, mainly Caridina spp. (n = 5, Neocaridina spp. (n = 4, Atyopsis moluccensis, Atya gabonensis, Arachnochium kulsiense and several taxa of exotic crabs (n = 5 belonging to three different genera (Cardiosoma, Geosesarma and Gecarinus present. Neocaridina davidi is identified as the most frequent in this regard. As some of the species can become established and form viable
Integrative Potential of Architectural Activities
Davydova, O. V.
2017-11-01
The architectural activity integrative potential is considered through the combination as well as the organization of necessary universal human and professional, artificial and natural, social and individual architectural activities in the multidimensional unity of its components reflecting and influencing the public thinking with the artistic-figurative language of international communication using experimental form-building, interactive presentations, theatrical and gaming expressiveness to organize an easier contact with the consumer, methods of design and advertising. The methodology is used to reflect the mutual influence of personal and social problems through globalization and identification of their problem in the public, to study the existing methods of the problem solving, to analyze their effectiveness, to search for actual problems and new solutions to them using the latest achievements of technological progress, artistic patterns, creation of a holistic architectural image reflecting the author’s worldview in the general picture of the modern world with its inherent tendencies “Surah” and “entertainment”. The operative communication means in the chain of social experience are developed - the teacher - the trainee - the new educational result used to transmit the updated information in a generalized form, the current and final control through the use of feedback sheets, supporting summaries, info cards, its decisions. The paper considers the study time efficiency due to the organization of the research activity which allows students to obtain a theoretical generalized information (the creator’s limitation) in the process of filling or compiling informative and diagnostic maps that provide the theoretical framework for the creative activity through gaming activity that turns into a work activity which has a diagnosed result.
Potential wine ageing during transportation
Directory of Open Access Journals (Sweden)
Jung Rainer
2014-01-01
Full Text Available In a global world, wineries have to satisfy the demand of consumers who wish to drink high quality wines from countries all over the world. To fulfill this request wines have to be transported, crossing thereby great distances from the place of production to the consumer country. At the Institute of Enology of Hochschule Geisenheim University examinations with White-, Rosé- and Red-Wines of different origins which had been transported over longer distances within Europe (Portugal, France, Italy to Germany by trucks were carried out. Shipping of wines was simulated in a climatized cabinet to analyze the influence on wine quality during this way and conditions of transportation. Time and temperature profiles were based on real transport situtations which were recorded during shipping from Germany to Japan using data loggers. White, Rosé and Red wines were transported during 6 to 8 weeks and then were analytically and sensorically compared to those which were stored at a constant temperature of 15 ∘C. Besides the effect of temperature, the movements and vibrations encountered by the wines were also examined. Analytically wines were analyzed for general analytical parameters with Fourier-Transformation-Infrared-Spectroscopie (FTIR, Colour differences (Spectralphotometrie and free and total sulfuric acid with Flow-Injection-Analysis (FIA. Sensory examinations with a trained panel were performed in difference tests in form of rankings and triangular tests. Summarizing the results from the different tests it could be found that transportation had an influence on the potential ageing of wines depending on the wine matrix. Especially high and varying temperatures during transportations over a longer distance and time had negative influences on wine quality. Also the movement of wine at higher temperatures had showed a negative effect whereas transport at cool temperatures even below 0 ∘C did not influence wine characteristics. Sophisticated
The potential of electric vehicles
International Nuclear Information System (INIS)
2016-04-01
Electric vehicles can help reduce the dependence of road transport on imported oil, cut the country's energy bill, reduce greenhouse gas emissions, improve air quality in cities through zero exhaust emissions and reduce noise pollution. The economic costs and environmental impacts of electric vehicles are mostly concentrated at the manufacturing stage, whereas the costs and impacts of internal combustion vehicles are predominantly felt during usage. So we cannot simply compare vehicles as objects, we must see how they are used, which means taking a fresh look at the full potential of electric vehicles which must be used intensely to be economically and environmentally viable. The main advantage of internal combustion vehicles is their ability to carry a very large amount of energy giving them a very large range and significant versatility. However, the consequences of the use of fossil fuels on the climate and the environment today require us to look for other solutions for vehicles and mobility systems. Electric vehicles are among these: its lack of versatility, due to its still limited range, is offset by being more adaptable and optimised for the usage sought. Electric vehicles are particularly suitable for new mobility services offerings and allow the transition to new ways of travelling to be speeded up optimising the use of the vehicle and no longer requiring ownership of it. The use of digital, facilitated by the electrical engine, opens up numerous opportunities for innovations and new services (such as the autonomous vehicle for example). In addition, electric vehicles can do more than just transport. Their batteries provide useful energy storage capabilities that can help regulate the power grid and the development of renewable energy. The marketing of electric vehicles may be accompanied by energy services that can be economically viable and used to structure the electro-mobility offer in return. To minimise the impact on the electrical grid, it is
Square well approximation to the optical potential
International Nuclear Information System (INIS)
Jain, A.K.; Gupta, M.C.; Marwadi, P.R.
1976-01-01
Approximations for obtaining T-matrix elements for a sum of several potentials in terms of T-matrices for individual potentials are studied. Based on model calculations for S-wave for a sum of two separable non-local potentials of Yukawa type form factors and a sum of two delta function potentials, it is shown that the T-matrix for a sum of several potentials can be approximated satisfactorily over all the energy regions by the sum of T-matrices for individual potentials. Based on this, an approximate method for finding T-matrix for any local potential by approximating it by a sum of suitable number of square wells is presented. This provides an interesting way to calculate the T-matrix for any arbitary potential in terms of Bessel functions to a good degree of accuracy. The method is applied to the Saxon-Wood potentials and good agreement with exact results is found. (author)
Exploring the potential of MAR
International Nuclear Information System (INIS)
Vanderzalm, Joanne
2014-01-01
Despite numerous benefits, the full potential for uptake of MAR for use of treated wastewater and urban stormwater has not been realised. CSIRO is currently leading research to address some of the major impediments to uptake of MAR. These include the clogging of the soil or aquifer matrix, leading to reduced infiltration rates; water quality impacts on the receiving aquifer; and uncertainty regarding the economics of MAR schemes. Field-scale application of MAR through national demonstration projects aims to reduce the uncertainty associated with technical and economic feasibility and facilitate water recycling via the aquifer. Current research in the Managed Aquifer Recharge and Recycling Options (MARRO) project provides two case studies using novel infiltration techniques, soil aquifer treatment (SAT) and infiltration galleries, to recharge treated wastewater for non-potable use. SAT at Alice Springs supplements existing groundwater resources for future irrigation supplies, while an infiltration gallery at Floreat (Western Australia) is evaluating the potential of MAR to sustain groundwater-fed wetlands. These infiltration techniques provide an opportunity to optimise the passive treatment processes and minimise water quality impacts on the receiving groundwater. SAT uses open infiltration basins operated intermittently to create alternate wet and dry cycles and optimise natural treatment processes within the subsurface. Power and Water Corporation's Alice Springs SAT scheme has been in operation since 2008 to prevent overflow of treated wastewater to surface water systems and augment the groundwater resource. Wastewater for recharge to a Quaternary sand and gravel aquifer is treated by stabilisation ponds and dissolved air flotation, with filtration added to the treatment train in late 2013. The scheme commenced as four basins with a total recharge area of 7,640 sq.m, but was increased to allow 600,000 m 3 /year recharge to the current, larger capacity of
Scalar potentials and the Dirac equation
International Nuclear Information System (INIS)
Bergerhoff, B.; Soff, G.
1994-01-01
The Dirac equation is solved for various types of scalar potentials. Energy eigenvalues and normalized bound-state wave functions are calculated analytically for a scalar 1/r-potential as well as for a mixed scalar and Coulomb 1/r-potential. Also continuum wave functions for positive and negative energies are derived. Similarly, we investigate the solutions of the Dirac equation for a scalar square-well potential. Relativistic wave functions for scalar Yukawa and exponential potentials are determined numerically. Finally, we also discuss solutions of the Dirac equation for scalar linear and quadratic potentials which are frequently used to simulate quark confinement. (orig.)
Green roofs: potential at LANL
Energy Technology Data Exchange (ETDEWEB)
Pacheco, Elena M [Los Alamos National Laboratory
2009-01-01
strokes, heat exhaustion, and pollution that can agitate the respiratory system. The most significant savings associated with green roofs is in the reduction of cooling demands due to the green roof's thermal mass and their insulating properties. Unlike a conventional roof system, a green roof does not absorb solar radiation and transfer that heat into the interior of a building. Instead the vegetation acts as a shade barrier and stabilizes the roof temperature so that interior temperatures remain comfortable for the occupants. Consequently there is less of a demand for air conditioning, and thus less money spent on energy. At LANL the potential of green roof systems has already been realized with the construction of the accessible green roof on the Otowi building. To further explore the possibilities and prospective benefits of green roofs though, the initial capital costs must be invested. Three buildings, TA-03-1698, TA-03-0502, and TA-53-0031 have all been identified as sound candidates for a green roof retrofit project. It is recommended that LANL proceed with further analysis of these projects and implementation of the green roofs. Furthermore, it is recommended that an urban forestry program be initiated to provide supplemental support to the environmental goals of green roofs. The obstacles barring green roof construction are most often budgetary and structural concerns. Given proper resources, however, the engineers and design professionals at LANL would surely succeed in the proper implementation of green roof systems so as to optimize their ecological and monetary benefits for the entire organization.
International Nuclear Information System (INIS)
Cari, C.; Suparmi, A.; Yunianto, M.; Pratiwi, B. N.
2016-01-01
Killingbeck radial potential, which consists of harmonic oscillator, linier and Coulomb potentials, is combined with non-central potential. The solution of three dimensional Schrodinger equation for Killingbeck potential is combined with Poschl-Teller potential and Symmetrical Top non-central potentials are investigated using supersymmetry (SUSY) operator. The non-relativistic energy is obtained which is infuenced by potentials and the wave functions are produced by using SUSY operator. (paper)
Supersymmetric quantum mechanics and new potentials
International Nuclear Information System (INIS)
Drigo Filho, E.
1988-01-01
Using the supersymmetric quantum mechanics the following potential are generalized. The particle in the box, Poeschl-Teller and Rosen-Morse. The new potentials are evaluated and their eigenfunctions and spectra are indicated. (author) [pt
Dual Eligibles and Potentially Avoidable Hospitalizations
U.S. Department of Health & Human Services — About 25 percent of the hospitalizations for dual eligible beneficiaries in 2005 were potentially avoidable. Medicare and Medicaid spending for those potentially...
Deforming tachyon kinks and tachyon potentials
International Nuclear Information System (INIS)
Afonso, Victor I.; Bazeia, Dionisio; Brito, Francisco A.
2006-01-01
In this paper we investigate deformation of tachyon potentials and tachyon kink solutions. We consider the deformation of a DBI type action with gauge and tachyon fields living on D1-brane and D3-brane world-volume. We deform tachyon potentials to get other consistent tachyon potentials by using properly a deformation function depending on the gauge field components. Resolutions of singular tachyon kinks via deformation and applications of deformed tachyon potentials to scalar cosmology scenario are discussed
Exactly solvable energy-dependent potentials
International Nuclear Information System (INIS)
Garcia-Martinez, J.; Garcia-Ravelo, J.; Pena, J.J.; Schulze-Halberg, A.
2009-01-01
We introduce a method for constructing exactly-solvable Schroedinger equations with energy-dependent potentials. Our method is based on converting a general linear differential equation of second order into a Schroedinger equation with energy-dependent potential. Particular examples presented here include harmonic oscillator, Coulomb and Morse potentials with various types of energy dependence.
Classification of geothermal resources by potential
Rybach, L.
2015-03-01
When considering and reporting resources, the term "geothermal potential" is often used without clearly stating what kind of potential is meant. For renewable energy resources it is nowadays common to use different potentials: theoretical, technical, economic, sustainable, developable - decreasing successively in size. In such a sequence, the potentials are progressively realizable and more and more rewarding financially. The theoretical potential describes the physically present energy, the technical potential the fraction of this energy that can be used by currently available technology and the economic potential the time- and location-dependent fraction of the previous category; the sustainable potential constrains the fraction of the economic potential that can be utilized in the long term; the developable potential is the fraction of the economic resource which can be developed under realistic conditions. In converting theoretical to technical potential, the recovery factor (the ratio extractable heat/heat present at depth) is of key importance. An example (global geothermal resources) is given, with numerical values of the various potentials. The proposed classification could and should be used as a kind of general template for future geothermal energy resources reporting.
Effective pair potentials for spherical nanoparticles
International Nuclear Information System (INIS)
Van Zon, Ramses
2009-01-01
An effective description for rigid spherical nanoparticles in a fluid of point particles is presented. The points inside the nanoparticles and the point particles are assumed to interact via spherically symmetric additive pair potentials, while the distribution of points inside the nanoparticles is taken to be spherically symmetric and smooth. The resulting effective pair interactions between a nanoparticle and a point particle, as well as between two nanoparticles, are then given by spherically symmetric potentials. If overlap between particles is allowed, as can occur for some forms of the pair potentials, the effective potential generally has non-analytic points. It is shown that for each effective potential the expressions for different overlapping cases can be written in terms of one analytic auxiliary potential. Even when only non-overlapping situations are possible, the auxiliary potentials facilitate the formulation of the effective potentials. Effective potentials for hollow nanoparticles (appropriate e.g. for buckyballs) are also considered and shown to be related to those for solid nanoparticles. For hollow nanoparticles overlap is more physical, since this covers the case of a smaller particle embedded in a larger, hollow nanoparticle. Finally, explicit expressions are given for the effective potentials derived from basic pair potentials of power law and exponential form, as well as from the commonly used London–van der Waals, Morse, Buckingham, and Lennard-Jones potentials. The applicability of the latter is demonstrated by comparison with an atomic description of nanoparticles with an internal face centered cubic structure
The Anthropology of Potentiality in Biomedicine
DEFF Research Database (Denmark)
Taussig, Karen-Sue; Hoeyer, Klaus; Helmreich, Stefan
2013-01-01
with potential. We suggest that anthropologists of the life sciences and biomedicine should work reflexively with the concept of potentiality and the politics of its naming and framing. We lay out a set of propositions and emphasize the moral aspects of claims about potentiality as well as the productivity...
Dynamic polarization potentials in heavy ion scattering
International Nuclear Information System (INIS)
Wolf, R.
1984-01-01
In this thesis the polarization potential is calculated which is caused by several collective, strongly coupled states. In the framework of the considered model space the calculation of the polarization potential was exact, i.e. no approximations were made. For this purpose the Green function of the system had to be calculated. This led to a nonlocal polarization potential. For the better interpretation possibility and for the easier use in coupled-channel or optical-model calculations from the nonlocal potentials also equivalent potentials were constructed. The properties of the local and nonlocal potentials as shape, angular momentum, and energy dependence were discussed. Furthermore parametrizations were given, how polarization effects can be regarded in a simple way in optical-model or coupled-channel calculations. The calculations were performed for the systems 12 C+ 12 C and 16 O+ 16 O. To meet as realistic results as possible, parameters for the unperturbed potential were looked for which describe as many data as possible, like angular distributions, excitation functions, and alignment of the main channels. As unperturbed potential both folding potentials and phenomenological potentials were applied in order to study the differences in the polarization potential in the application of deep and flat potentials. (orig./HSI) [de
The electromagnetic potentials without the gauge transformations
Energy Technology Data Exchange (ETDEWEB)
Espinoza, Augusto; Chubykalo, Andrey; Rodriguez, Alejandro Gutierrez; Hernandez, Maria de los Angeles [Universidad Autonoma de Zacatecas (Mexico). Unidad Academica de Fisica
2011-07-01
In this note we show that the use of the Helmholtz theorem lead to derivation of uniquely determined electromagnetic potentials without making use of the gauge transformation. These potentials correspond to the potentials obtained by imposing so-called Coulomb condition (gauge) in the traditional approach. We show that the electromagnetic field comprises two components, one of which is characterized by its instantaneous action at a distance, whereas another one propagates in the retarded form with the velocity of light. One of the theoretical consequences of this new definition is that the electromagnetic potentials are real physical quantities as well as the electric and magnetic fields. We show that the reality of the electromagnetic potentials in quantum-mechanics is also a property of these potentials in the classical electrodynamics. Equations for potentials obtained in our approach are already separated with respect to vector and scalar potentials, so there is no necessity in using the gauge transformations and, accordingly, in making use of either Lorentz or Coulomb condition. The vector potential and scalar potential introduced thus are uniquely defined. The scalar potential is a generator of the so called instantaneous action at a distance, whereas the solenoidal vector potential can propagate with the velocity of light and it is responsible for the retarded action of the electromagnetic field. (author)
Potential and profile experiments in MM-4
International Nuclear Information System (INIS)
Tian Zhongyu; Ming Linzhou; Feng Xiaozhen; Feng Chuntang; Yin Youjun; Liu Yuhua; Wang Jihai
1988-01-01
Experimental results in MM-4 are presented. These results show that there were double potential wells and double ion temperatures in the plasma. The mechanism giving rise to such potential profiles can be attributed to the Stormer region in the cusp system and the different operation regimes of the electron gun used. The measured plasma potential was about - 200 - 300V
Iterated interactions method. Realistic NN potential
International Nuclear Information System (INIS)
Gorbatov, A.M.; Skopich, V.L.; Kolganova, E.A.
1991-01-01
The method of iterated potential is tested in the case of realistic fermionic systems. As a base for comparison calculations of the 16 O system (using various versions of realistic NN potentials) by means of the angular potential-function method as well as operators of pairing correlation were used. The convergence of genealogical series is studied for the central Malfliet-Tjon potential. In addition the mathematical technique of microscopical calculations is improved: new equations for correlators in odd states are suggested and the technique of leading terms was applied for the first time to calculations of heavy p-shell nuclei in the basis of angular potential functions
Conduction velocity of antigravity muscle action potentials.
Christova, L; Kosarov, D; Christova, P
1992-01-01
The conduction velocity of the impulses along the muscle fibers is one of the parameters of the extraterritorial potentials of the motor units allowing for the evaluation of the functional state of the muscles. There are no data about the conduction velocities of antigravity muscleaction potentials. In this paper we offer a method for measuring conduction velocity of potentials of single MUs and the averaged potentials of the interference electromiogram (IEMG) lead-off by surface electrodes from mm. sternocleidomastoideus, trapezius, deltoideus (caput laterale) and vastus medialis. The measured mean values of the conduction velocity of antigravity muscles potentials can be used for testing the functional state of the muscles.
Remote RemoteRemoteRemote sensing potential for sensing ...
African Journals Online (AJOL)
Remote RemoteRemoteRemote sensing potential for sensing potential for sensing potential for sensing potential for sensing potential for sensing potential for sensing potential for sensing potential for sensing potential for sensing potential for sensing p. A Ngie, F Ahmed, K Abutaleb ...
Calculation of baryon chemical potential and strangeness chemical potential in resonance matter
International Nuclear Information System (INIS)
Fu Yuanyong; Hu Shouyang; Lu Zhongdao
2006-01-01
Based on the high energy heavy-ion collisions statistical model, the baryon chemical potential and strangeness chemical potential are calculated for resonance matter with net baryon density and net strangeness density under given temperature. Furthermore, the relationship between net baryon density, net strangeness density and baryon chemical potential, strangeness chemical potential are analyzed. The results show that baryon chemical potential and strangeness chemical potential increase with net baryon density and net strangeness density increasing, the change of net baryon density affects baryon chemical potential and strangeness chemical potential more strongly than the change of net strangeness density. (authors)
Indoor radon risk potential of Hawaii
International Nuclear Information System (INIS)
Reimer, G.M.; Szarzi, S.L.
2005-01-01
A comprehensive evaluation of radon risk potential in the State of Hawaii indicates that the potential for Hawaii is low. Using a combination of factors including geology, soils, source-rock type, soil-gas radon concentrations, and indoor measurements throughout the state, a general model was developed that permits prediction for various regions in Hawaii. For the nearly 3,100 counties in the coterminous U.S., National Uranium Resource Evaluation (NURE) aerorad data was the primary input factor. However, NURE aerorad data was not collected in Hawaii, therefore, this study used geology and soil type as the primary and secondary components of potential prediction. Although the radon potential of some Hawaiian soils suggests moderate risk, most houses are built above ground level and the radon soil potential is effectively decoupled from the house. Only underground facilities or those with closed or recirculating ventilation systems might have elevated radon potential. (author)
Research potential and cognitive features of students.
Directory of Open Access Journals (Sweden)
Bordovskaia N.V.
2014-12-01
Full Text Available This article examines the theoretical and methodological justifications for studying students’ research potential. It presents proof of the isomorphic nature of human research activity and research potential as well as of the fluid nature of its development: from research-like behavior to science-based research activity. It defines three functional components (motivational, cognitive, and behavioral that form the structure of research potential. It further presents the results of empirically studying the cognitive features of master’s students possessing different levels of research potential. It provides data on the dynamics of research-potential components at different educational levels (bachelor’s and master’s programs. Special attention is given to a comparative analysis of evaluations by research tutors regarding their students’ research potential and of the indicators obtained using psychodiagnostic methods.
Enterprise Potential: Essence, Classification and Types
Directory of Open Access Journals (Sweden)
Turylo Anatolii M.
2014-02-01
Full Text Available The article considers existing approaches to classification of the enterprise potential as an economic notion. It offers own vision of classification of enterprise potential, which meets modern tendencies of enterprise development. Classification ensures a possibility of a wider description and assessment of enterprise potential and also allows identification of its most significant characteristics. Classification of the enterprise potential is developed by different criteria: by functions, by resource support, by ability to adapt, by the level of detection, by the spectrum of taking into account possibilities, by the period of coverage of possibilities and by the level of use. Analysis of components of the enterprise potential allows obtaining a complete and trustworthy assessment of the state of an enterprise. Adaptation potential of an enterprise is based on principles systemacy and dynamism, it characterises possibilities of adjustment of an enterprise to external and internal economic conditions.
On transparent potentials: a Born approximation study
International Nuclear Information System (INIS)
Coudray, C.
1980-01-01
In the frame of the scattering inverse problem at fixed energy, a class of potentials transparent in Born approximation is obtained. All these potentials are spherically symmetric and are oscillating functions of the reduced radial variable. Amongst them, the Born approximation of the transparent potential of the Newton-Sabatier method is found. In the same class, quasi-transparent potentials are exhibited. Very general features of potentials transparent in Born approximation are then stated. And bounds are given for the exact scattering amplitudes corresponding to most of the potentials previously exhibited. These bounds, obtained at fixed energy, and for large values of the angular momentum, are found to be independent on the energy
A parabolic model for dimple potentials
International Nuclear Information System (INIS)
Aydin, Melike Cibik; Uncu, Haydar; Deniz, Coskun
2013-01-01
We study the truncated parabolic function and demonstrate that it is a representation of the Dirac δ function. We also show that the truncated parabolic function, used as a potential in the Schrödinger equation, has the same bound state spectrum, tunneling and reflection amplitudes as the Dirac δ potential, as the width of the parabola approximates to zero. Dirac δ potential is used to model dimple potentials which are utilized to increase the phase-space density of a Bose–Einstein condensate in a harmonic trap. We show that a harmonic trap with a δ function at the origin is a limiting case of the harmonic trap with a symmetric truncated parabolic potential around the origin. Hence, the truncated parabolic is a better candidate for modeling the dimple potentials. (paper)
Electrode breakdown potentials in MHD plasmas
International Nuclear Information System (INIS)
Sodha, M.S.; Raju, G.V.R.; Kumar, A.S.; Gupta, Bhumesh
1988-01-01
Electrode breakdown potentials and current densities have been calculated for both the thermionically electron emitting and non-emitting cathodes. Calculated values have been compared with the available experimental results. It is found that the cathode potential drop for the breakdown is almost unaffected by the emission. However, both the total potential difference between the anode and the cathode and the current density at the breakdown are higher for electron-emitting cathodes than for non-emitting cathodes. (author)
Dynamical equations for the optical potential
International Nuclear Information System (INIS)
Kowalski, K.L.
1981-01-01
Dynamical equations for the optical potential are obtained starting from a wide class of N-particle equations. This is done with arbitrary multiparticle interactions to allow adaptation to few-body models of nuclear reactions and including all effects of nucleon identity. Earlier forms of the optical potential equations are obtained as special cases. Particular emphasis is placed upon obtaining dynamical equations for the optical potential from the equations of Kouri, Levin, and Tobocman including all effects of particle identity
Potential radiation doses from 1994 Hanford Operations
Energy Technology Data Exchange (ETDEWEB)
Soldat, J.K.; Antonio, E.J.
1995-06-01
This section of the 1994 Hanford Site Environmental Report summarizes the potential radiation doses to the public from releases originating at the Hanford Site. Members of the public are potentially exposed to low-levels of radiation from these effluents through a variety of pathways. The potential radiation doses to the public were calculated for the hypothetical MEI and for the general public residing within 80 km (50 mi) of the Hanford Site.
Actual and Potential Electoral Absenteeism in Belgium
ACKAERT, Johan; DUMONT, P.; DE WINTER, L.
2007-01-01
During the eighties and nineties of the 20th century, absenteeism increased in Belgium. This evolution ended for all types of elections at the beginning of the current century. This paper offered a number of potential explanations for this puzzle, but we acknowledge that further examination is necessary to provide a clear answer for this change. We showed that potential absenteeists share specific characteristics. Potential turnout (in case of abolishment of compulsory voting) ...
Verification of the SLC wake potentials
International Nuclear Information System (INIS)
Bane, K.; Weiland, T.
1983-01-01
The accurate knowledge of the monopole, dipole, and quadrupole wake potentials is essential for SLC. These wake potentials were previously computed by the modal method. The time domain code TBCI allows independent verification of these results. This comparison shows that the two methods agree to within 10% for bunch lengths down to 1 mm. TBCI results also indicate that rounding the irises gives at least a 10% reduction in the wake potentials
Interatomic potentials for materials of nuclear interest
International Nuclear Information System (INIS)
Fernandez, Julian R.; Monti, Ana M.; Pasianot, Roberto C.; Simonelli, G.
2007-01-01
Procedures to develop embedded atom method (EAM) interatomic potentials are described, with foreseeable applications in nuclear materials. Their reliability is shown by evaluating relevant properties. The studied materials are Nb, Zr and U. The first two were then used to develop an inter species potential for the Zr-Nb binary system. In this sense, the Fe-Cu system was also studied starting from Fe and Cu potentials extracted from the literature. (author) [es
Standard Model Effective Potential from Trace Anomalies
Directory of Open Access Journals (Sweden)
Renata Jora
2018-01-01
Full Text Available By analogy with the low energy QCD effective linear sigma model, we construct a standard model effective potential based entirely on the requirement that the tree level and quantum level trace anomalies must be satisfied. We discuss a particular realization of this potential in connection with the Higgs boson mass and Higgs boson effective couplings to two photons and two gluons. We find that this kind of potential may describe well the known phenomenology of the Higgs boson.
Potential radiation doses from 1994 Hanford Operations
International Nuclear Information System (INIS)
Soldat, J.K.; Antonio, E.J.
1995-01-01
This section of the 1994 Hanford Site Environmental Report summarizes the potential radiation doses to the public from releases originating at the Hanford Site. Members of the public are potentially exposed to low-levels of radiation from these effluents through a variety of pathways. The potential radiation doses to the public were calculated for the hypothetical MEI and for the general public residing within 80 km (50 mi) of the Hanford Site
Pumped Storage and Potential Hydropower from Conduits
Energy Technology Data Exchange (ETDEWEB)
none,
2015-02-25
Th is Congressional Report, Pumped Storage Hydropower and Potential Hydropower from Conduits, addresses the technical flexibility that existing pumped storage facilities can provide to support intermittent renewable energy generation. This study considered potential upgrades or retrofit of these facilities, the technical potential of existing and new pumped storage facilities to provide grid reliability benefits, and the range of conduit hydropower opportunities available in the United States.
One parameter model potential for noble metals
International Nuclear Information System (INIS)
Idrees, M.; Khwaja, F.A.; Razmi, M.S.K.
1981-08-01
A phenomenological one parameter model potential which includes s-d hybridization and core-core exchange contributions is proposed for noble metals. A number of interesting properties like liquid metal resistivities, band gaps, thermoelectric powers and ion-ion interaction potentials are calculated for Cu, Ag and Au. The results obtained are in better agreement with experiment than the ones predicted by the other model potentials in the literature. (author)
Characterization qualitative and potentialities of utilization of ...
African Journals Online (AJOL)
Characterization qualitative and potentialities of utilization of methacomposts of poultry in the nurseries aboveground. ... PROMOTING ACCESS TO AFRICAN RESEARCH. AFRICAN ... Journal of Fundamental and Applied Sciences.
Measurement of human potential in organizations
Directory of Open Access Journals (Sweden)
Rosa María Fuchs Ángeles
2015-09-01
Full Text Available Companies around the world are concerned about talent management in their organizations. The concern is to retain talented employees and this may not be possible if they are not properly identified. Performance and potential evaluations become then important. Performance evaluations qualify the historical record of the employee, so their measurement is provided. However, measuring the potential performance assesses potential future charges, therefore it is not a simple task. In this paper, characteristics evaluated in potential employees and tools that are commonly used are presented. Also, the case of four companies operating in Peru is shown.
On the generalized potential of inertial forces
International Nuclear Information System (INIS)
Siboni, S
2009-01-01
The generalized potential of the inertial forces acting on a holonomic system in an accelerated reference frame is derived in a way which admits a simple physical interpretation. It is shown that the generalized potential refers to all the inertial forces and, apart from the very special case of a uniformly rotating frame, it is impossible to distinguish a contribution to only the Coriolis force and a contribution pertaining to the residual, velocity-independent fictitious forces. Such an approach to the determination of the generalized potential of inertial forces may be helpful in introducing the topic of the generalized potential to advanced undergraduate and graduate students
Geophysical Processes - MO 2013 Collapse Potential (SHP)
NSGIC State | GIS Inventory — Collapse potential correlates with locations of underground mines and sinkholes. Computer-generated hazard calculations include areas in close proximity to mines and...
An Introduction to LANL Mixed Potential Sensors
Energy Technology Data Exchange (ETDEWEB)
Mukundan, Rangachary [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Brosha, Eric Lanich [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Kreller, Cortney [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
2015-01-26
These are slides for a webinar given on the topics of an introduction to LANL mixed potential sensors. Topics include the history of LANL electrochemical sensor work, an introduction to mixed potential sensors, LANL uniqueness, and an application of LANL mixed potential sensors. The summary is as follows: Improved understanding of the mixed-potential sensor mechanism (factors controlling the sensor response identified), sensor design optimized to maximize sensor sensitivity and durability (porous electrolyte/dense electrodes), electrodes selected for various specific applications (CO, HC, H_{2}), sensor operating parameters optimized for improved gas selectivity (NO_{x}, NH_{3}).
Aquifer Characterization and Groundwater Potential Assessment
African Journals Online (AJOL)
Timothy Ademakinwa
Keywords: Aquifer Characterization, Groundwater Potential, Electrical Resistivity, Lithologic Logs ... State Water Corporation currently cannot meet the daily water ... METHOD OF STUDY ... sections which were constrained with the available.
Suparmi; Cari, C.; Wea, K. N.; Wahyulianti
2018-03-01
The Schrodinger equation is the fundamental equation in quantum physics. The characteristic of the particle in physics potential field can be explained by using the Schrodinger equation. In this study, the solution of 4 dimensional Schrodinger equation for the anharmonic potential and the anharmonic partner potential have done. The method that used to solve the Schrodinger equation was the ansatz wave method, while to construction the partner potential was the supersymmetric method. The construction of partner potential used to explain the experiment result that cannot be explained by the original potential. The eigenvalue for anharmonic potential and the anharmonic partner potential have the same characteristic. Every increase of quantum orbital number the eigenvalue getting smaller. This result corresponds to Bohrn’s atomic theory that the eigenvalue is inversely proportional to the atomic shell. But the eigenvalue for the anharmonic partner potential higher than the eigenvalue for the anharmonic original potential.
Unjamming in models with analytic pairwise potentials
Kooij, S.; Lerner, E.
Canonical models for studying the unjamming scenario in systems of soft repulsive particles assume pairwise potentials with a sharp cutoff in the interaction range. The sharp cutoff renders the potential nonanalytic but makes it possible to describe many properties of the solid in terms of the
Algebraic approach to the Kratzer potential
International Nuclear Information System (INIS)
Setare, Mohammad R; Karimi, Ebrahim
2007-01-01
In this paper, the energy eigenvalues and the corresponding eigenfunctions are calculated for the Kratzer potential. Then we obtain the ladder operators for the one-dimensional (1D) and 3D Kratzer potential. Finally, we show that these operators satisfy the SU(2) commutation relation
Developing simplified Regional Potential Evapotranspiration (PET ...
African Journals Online (AJOL)
Regional Potential Evapotranspiration (PET) estimation method was developed to estimate the potential evapotranspiration (reference evapotranspiration) over Abbay Basin as a function of basin maximum and minimum temperature, and modulated by site specific elevation data. The method is intended to estimate PET in ...
Comparison of potentials for polymeric liquids
International Nuclear Information System (INIS)
Jung, Hae Young
2002-01-01
Many theories for polymeric liquids are based on the concepts of cell, hole, free volume of lattice etc. In this theories, van der Waals potential, Lennard-Jones 6-12 potential and their modified potentials are commonly used. In this work, Mie(p,6)potential was applied to the Continuous Lattice Fluid Theory (which extends the discrete lattices of Lattice Fluid Theory to classically continuous lattices) and Dee-Walsch's Cell Theory (which modifies Flory's Equation of State Theory). Both of them are known to be successful theories for polymeric liquids. Thus, PVT values changing with p (the exponent in the repulsion potential) were calculated and compared with experimental values. And, calculated values of Lattice Fluid theory, Flory's Equation of State Theory and Cho-Sanchez Theory using perturbation method were also compared. Through the calculated results, van der Waals potential, Lennard-Jones 6-12 potential and Mie(p,6) potential for polymeric liquids were compared with each other
Potential biosurfactant producing endophytic and epiphytic fungi ...
African Journals Online (AJOL)
Potential biosurfactant producing endophytic and epiphytic fungi, isolated from macrophytes in the Negro River in Manaus, Amazonas, Brazil. ... Solms and Cyperus ligularis L., macrophytes collected from oil-contaminated waters, were studied to assess their potential for producing biosurfactants; the most promising ones ...
A correction to the Watanabe potential
International Nuclear Information System (INIS)
Abul-Magd, A.Y.; Rabie, A.; El-Gazzar, M.A.
1980-10-01
Using the adiabatic approximation, an analytic expression for the correction to the Watanabe potential was obtained. In addition, we have corrected through a proper choice of the energy at which the potential parameters of the constituents of 6 Li should be taken. (author)
Nuclear potentials due to pion exchange
International Nuclear Information System (INIS)
Robillota, M.R.
1984-01-01
The two, three and four nucleon potentials due to the exchange of pions can be accurately calculated by means of chiral symmetry. The comparison of the dynamical content of these potentials allow us to understand the geometrical origin of the hierarchy existing among them. (Author) [pt
Potential roughness near lithographically fabricated atom chips
DEFF Research Database (Denmark)
Krüger, Peter; Andersson, L. M.; Wildermuth, Stefan
2007-01-01
Potential roughness has been reported to severely impair experiments in magnetic microtraps. We show that these obstacles can be overcome as we measure disorder potentials that are reduced by two orders of magnitude near lithographically patterned high-quality gold layers on semiconductor atom chip...
Abelian gauge potentials on cubic lattices
DEFF Research Database (Denmark)
Burrello, M.; Lepori, L.; Paganelli, S.
2017-01-01
The study of the properties of quantum particles in a periodic potential subjected to a magnetic field is an active area of research both in physics and mathematics, and it has been and is yet deeply investigated. In this chapter we discuss how to implement and describe tunable Abelian magnetic...... potentials in one-dimensional rings....
YouTube: Educational Potentials and Pitfalls
Jones, Troy; Cuthrell, Kristen
2011-01-01
The instructional potential of video technology in the classroom is promising, especially in light of the 21st Century Learning Framework (Siegle, 2009). Studies show positive gains in student outcomes as a result of the integration of video technology in instruction. This article explores potential uses of YouTube as an instructional aid in…
Skin Potential as an Indicator of Emotion
Seligman, Linda
1975-01-01
The skin-potential responses of six college students were monitored while each was seen for 10 counseling sessions. Negative skin-potential responses were accompanied by feelings described as pleasant and released; positive responses were associated with unpleasant and inhibited feelings; and neutral responses were often associated with unpleasant…
The unification of the nuclear optical potential
International Nuclear Information System (INIS)
Hodgson, P.E.
1990-01-01
The nuclear mean field is defined for bound and scattering states and its parameters shown to vary continuously over the whole energy range. The real and imaginary parts of the potential are connected by dispersion relations, and this unifies the potential from negative to positive energies. Recent analyses of experimental data using dispersion relations are reviewed. (author)
Heavy quarkonium properties from Cornell potential using ...
Indian Academy of Sciences (India)
2016-10-08
Oct 8, 2016 ... energy in the usual Schrödinger equation. This potential picture ... believe that it could be interesting to start from a more realistic wave function, ... is a technique that allows us to get isospectral potentials for the Schrödinger ...
Identification of potentially competing Afrotropical and Palaearctic ...
African Journals Online (AJOL)
Identification of potentially competing Afrotropical and Palaearctic bird species in the Sahel. Jared M Wilson, Will RL Cresswell. Abstract. Areas experiencing a seasonal influx of migrants may be expected to have a high potential for competition between resident and migrant populations. Described differences in foraging ...
Streaming potential near a rotating porous disk.
Prieve, Dennis C; Sides, Paul J
2014-09-23
Theory and experimental results for the streaming potential measured in the vicinity of a rotating porous disk-shaped sample are described. Rotation of the sample on its axis draws liquid into its face and casts it from the periphery. Advection within the sample engenders streaming current and streaming potential that are proportional to the zeta potential and the disk's major dimensions. When Darcy's law applies, the streaming potential is proportional to the square of the rotation at low rate but becomes invariant with rotation at high rate. The streaming potential is invariant with the sample's permeability at low rate and is proportional to the inverse square of the permeability at high rate. These predictions were tested by determining the zeta potential and permeability of the loop side of Velcro, a sample otherwise difficult to characterize; reasonable values of -56 mV for zeta and 8.7 × 10(-9) m(2) for the permeability were obtained. This approach offers the ability to determine both the zeta potential and the permeability of materials having open structures. Compressing them into a porous plug is unnecessary. As part of the development of the theory, a convenient formula for a flow-weighted volume-averaged space-charge density of the porous medium, -εζ/k, was obtained, where ε is the permittivity, ζ is the zeta potential, and k is the Darcy permeability. The formula is correct when Smoluchowski's equation and Darcy's law are both valid.
Black Hole Dynamic Potentials Koustubh Ajit Kabe
Indian Academy of Sciences (India)
Abstract. In the following paper, certain black hole dynamic potentials have been developed definitively on the lines of classical thermodynam- ics. These potentials have been refined in view of the small differences in the equations of the laws of black hole dynamics as given by Bekenstein and those of thermodynamics.
Gravitational Waves from Oscillons with Cuspy Potentials.
Liu, Jing; Guo, Zong-Kuan; Cai, Rong-Gen; Shiu, Gary
2018-01-19
We study the production of gravitational waves during oscillations of the inflaton around the minimum of a cuspy potential after inflation. We find that a cusp in the potential can trigger copious oscillon formation, which sources a characteristic energy spectrum of gravitational waves with double peaks. The discovery of such a double-peak spectrum could test the underlying inflationary physics.
The erosive potential of candy sprays
Gambon, D.L.; Brand, H.S.; Nieuw Amerongen, A.V.
2009-01-01
Objective To determine the erosive potential of seven different commercially available candy sprays in vitro and in vivo. Material and methods The erosive potential was determined in vitro by measuring the pH and neutralisable acidity. The salivary pH and flow rate were measured in healthy
Dysfunctional methods and the effective potential
International Nuclear Information System (INIS)
Dannenberg, A.; California Univ., Berkeley
1988-01-01
The effective potential is a useful and much-studied object. It is known to be both real and convex, but a perturbative calculation often gives a complex and nonconvex result. In this letter we address the apparent conflict between perturbation theory and the convexity of the effective potential. (orig.)
Comparative study of quantum anharmonic potentials
International Nuclear Information System (INIS)
Amore, Paolo; Aranda, Alfredo; De Pace, Arturo; Lopez, Jorge A.
2004-01-01
We perform a study of various anharmonic potentials using a recently developed method. We calculate both the wave functions and the energy eigenvalues for the ground and first excited states of the quartic, sextic and octic potentials with high precision, comparing the results with other techniques available in the literature
Nonresonant approximations to the optical potential
International Nuclear Information System (INIS)
Kowalski, K.L.
1982-01-01
A new class of approximations to the optical potential, which includes those of the multiple-scattering variety, is investigated. These approximations are constructed so that the optical potential maintains the correct unitarity properties along with a proper treatment of nucleon identity. The special case of nucleon-nucleus scattering with complete inclusion of Pauli effects is studied in detail. The treatment is such that the optical potential receives contributions only from subsystems embedded in their own physically correct antisymmetrized subspaces. It is found that a systematic development of even the lowest-order approximations requires the use of the off-shell extension due to Alt, Grassberger, and Sandhas along with a consistent set of dynamical equations for the optical potential. In nucleon-nucleus scattering a lowest-order optical potential is obtained as part of a systematic, exact, inclusive connectivity expansion which is expected to be useful at moderately high energies. This lowest-order potential consists of an energy-shifted (trho)-type term with three-body kinematics plus a heavy-particle exchange or pickup term. The natural appearance of the exchange term additivity in the optical potential clarifies the role of the elastic distortion in connection with the treatment of these processes. The relationship of the relevant aspects of the present analysis of the optical potential to conventional multiple scattering methods is discussed
Optimized non relativistic potential for quarkonium
International Nuclear Information System (INIS)
Rekab, S.; Zenine, N.
2006-01-01
For non relativistic quarkonia description, we consider a wide class of quark antiquark potentials in the form of power law. A systematic study is made by optimizing the potential parameters with a fit on quarkonia vector mesons that lie below the threshold for strong decays. Implications of the obtained results are discussed
Transient receptor potential channels in essential hypertension
DEFF Research Database (Denmark)
Liu, Daoyan; Scholze, Alexandra; Zhu, Zhiming
2006-01-01
The role of nonselective cation channels of the transient receptor potential channel (TRPC) family in essential hypertension has not yet been investigated.......The role of nonselective cation channels of the transient receptor potential channel (TRPC) family in essential hypertension has not yet been investigated....
Simulation of action potential propagation in plants.
Sukhov, Vladimir; Nerush, Vladimir; Orlova, Lyubov; Vodeneev, Vladimir
2011-12-21
Action potential is considered to be one of the primary responses of a plant to action of various environmental factors. Understanding plant action potential propagation mechanisms requires experimental investigation and simulation; however, a detailed mathematical model of plant electrical signal transmission is absent. Here, the mathematical model of action potential propagation in plants has been worked out. The model is a two-dimensional system of excitable cells; each of them is electrically coupled with four neighboring ones. Ion diffusion between excitable cell apoplast areas is also taken into account. The action potential generation in a single cell has been described on the basis of our previous model. The model simulates active and passive signal transmission well enough. It has been used to analyze theoretically the influence of cell to cell electrical conductivity and H(+)-ATPase activity on the signal transmission in plants. An increase in cell to cell electrical conductivity has been shown to stimulate an increase in the length constant, the action potential propagation velocity and the temperature threshold, while the membrane potential threshold being weakly changed. The growth of H(+)-ATPase activity has been found to induce the increase of temperature and membrane potential thresholds and the reduction of the length constant and the action potential propagation velocity. Copyright © 2011 Elsevier Ltd. All rights reserved.
Superfield tadpole method for SUSY effective potential
International Nuclear Information System (INIS)
Srivastava, P.P.
1983-01-01
Superfield formulation of Weinberg's tadpole method to compute the effective potential in supersymmetric theories is illustrated by considering the general renormalizable action involving only chiral scalar superfields. Unconstrained superfield potentials are introduced to simplify the ''effective'' superfield propagator which is derived in a compact form. (orig.)
Isotopic effects in sub-barrier fusion of Si + Si systems
Colucci, G.; Montagnoli, G.; Stefanini, A. M.; Esbensen, H.; Bourgin, D.; Čolović, P.; Corradi, L.; Faggian, M.; Fioretto, E.; Galtarossa, F.; Goasduff, A.; Grebosz, J.; Haas, F.; Mazzocco, M.; Scarlassara, F.; Stefanini, C.; Strano, E.; Szilner, S.; Urbani, M.; Zhang, G. L.
2018-04-01
Background: Recent measurements of fusion cross sections for the 28Si+28Si system revealed a rather unsystematic behavior; i.e., they drop faster near the barrier than at lower energies. This was tentatively attributed to the large oblate deformation of 28Si because coupled-channels (CC) calculations largely underestimate the 28Si+28Si cross sections at low energies, unless a weak imaginary potential is applied, probably simulating the deformation. 30Si has no permanent deformation and its low-energy excitations are of a vibrational nature. Previous measurements of this system reached only 4 mb, which is not sufficient to obtain information on effects that should show up at lower energies. Purpose: The aim of the present experiment was twofold: (i) to clarify the underlying fusion dynamics by measuring the symmetric case 30Si+30Si in an energy range from around the Coulomb barrier to deep sub-barrier energies, and (ii) to compare the results with the behavior of 28Si+28Si involving two deformed nuclei. Methods: 30Si beams from the XTU tandem accelerator of the Laboratori Nazionali di Legnaro of the Istituto Nazionale di Fisica Nucleare were used, bombarding thin metallic 30Si targets (50 μ g /cm2) enriched to 99.64 % in mass 30. An electrostatic beam deflector allowed the detection of fusion evaporation residues (ERs) at very forward angles, and angular distributions of ERs were measured. Results: The excitation function of 30Si+30Si was measured down to the level of a few microbarns. It has a regular shape, at variance with the unusual trend of 28Si+28Si . The extracted logarithmic derivative does not reach the LCS limit at low energies, so that no maximum of the S factor shows up. CC calculations were performed including the low-lying 2+ and 3- excitations. Conclusions: Using a Woods-Saxon potential the experimental cross sections at low energies are overpredicted, and this is a clear sign of hindrance, while the calculations performed with a M3Y + repulsion
BCS equations in the continuum
International Nuclear Information System (INIS)
Sandulescu, N.; Liotta, R. J.; Wyss, R.
1998-01-01
with the next shells of an infinite depth potential or with the positive energies provided by a diagonalization of a Woods-Saxon potential in an oscillator basis, even if the positive energies would correspond to the centroids of the resonant states. The influence of the resonant continuum on pairing correlations should be calculated self-consistently with the mean field (HF + BCS) but the gap is not changing very much as expected. (authors)
Band gaps for the relativistic Mathieu potential
International Nuclear Information System (INIS)
Clerk, G.J.; McKellar, B.H.J.
1992-01-01
A study of the band structure of a massless particle in a cosine potential is made via the Dirac equation. It is shown that every alternate band gap disappears as a consequence of a periodicity of the potential combined with a peculiar symmetry of the Dirac equation. This basic potential is then used to study a simple one-dimensional model of the nucleus from which it is ascertained that modelling the mean field of the quarks in the nucleus via a pure scalar potential is unsatisfactory. A simple extension involving a combined scalar and vector potential is then proposed as a possible solution to this problem. The effect of the addition of this vector component to the band structure is also investigated. 32 refs
Atom-surface potentials and atom interferometry
International Nuclear Information System (INIS)
Babb, J.F.
1998-01-01
Long-range atom-surface potentials characterize the physics of many actual systems and are now measurable spectroscopically in deflection of atomic beams in cavities or in reflection of atoms in atomic fountains. For a ground state, spherically symmetric atom the potential varies as -1/R 3 near the wall, where R is the atom-surface distance. For asymptotically large distances the potential is weaker and goes as -1/R 4 due to retardation arising from the finite speed of light. This diminished interaction can also be interpreted as a Casimir effect. The possibility of measuring atom-surface potentials using atomic interferometry is explored. The particular cases studied are the interactions of a ground-state alkali-metal atom and a dielectric or a conducting wall. Accurate descriptions of atom-surface potentials in theories of evanescent-wave atomic mirrors and evanescent wave-guided atoms are also discussed. (author)
Constant potential high-voltage generator
International Nuclear Information System (INIS)
Resnick, T.A.; Dupuis, W.A.; Palermo, T.
1980-01-01
An X-ray tube voltage generator with automatic stabilization circuitry is disclosed. The generator includes a source of pulsating direct current voltage such as from a rectified 3 phase transformer. This pulsating voltage is supplied to the cathode and anode of an X-ray tube and forms an accelerating potential for electrons within that tube. The accelerating potential is stabilized with a feedback signal which is provided by a feedback network. The network includes an error signal generator which compares an instantaneous accelerating potential with a preferred reference accelerating potential and generates an error function. This error function is transmitted to a control tube grid which in turn causes the voltage difference between X-ray tube cathode and anode to stabilize and thereby reduce the error function. In this way stabilized accelerating potentials are realized and uniform X-ray energy distributions produced. (Auth.)
Effective exchange potentials for electronically inelastic scattering
International Nuclear Information System (INIS)
Schwenke, D.W.; Staszewska, G.; Truhlar, D.G.
1983-01-01
We propose new methods for solving the electron scattering close coupling equations employing equivalent local exchange potentials in place of the continuum-multiconfiguration-Hartree--Fock-type exchange kernels. The local exchange potentials are Hermitian. They have the correct symmetry for any symmetries of excited electronic states included in the close coupling expansion, and they have the same limit at very high energy as previously employed exchange potentials. Comparison of numerical calculations employing the new exchange potentials with the results obtained with the standard nonlocal exchange kernels shows that the new exchange potentials are more accurate than the local exchange approximations previously available for electronically inelastic scattering. We anticipate that the new approximations will be most useful for intermediate-energy electronically inelastic electron--molecule scattering
The Maritime Potential of ASEAN Economies
Directory of Open Access Journals (Sweden)
Hans-Dieter Evers
2011-01-01
Full Text Available Countries may utilize a long coastline in relation to their landmass as a resource to develop their maritime economy. This paper argues that ASEAN countries differ in utilizing their maritime potential. As a basis for further comparative studies the Center for Policy Research and International Studies (CenPRIS in Penang developed a set of indicators to measure the maritime potential of nations, the state of their maritime industries, and the degree to which the maritime potential has actually been utilized. Using the CenPRIS Ocean Index (COI shows that Brunei and the Philippines have underutilized their maritime potentials, whereas Singapore and Thailand have made full use of it. Malaysia still has the potential to further develop its maritime economy.
Simple exercises to flatten your potential
Energy Technology Data Exchange (ETDEWEB)
Dong, Xi; Horn, Bart; Silverstein, Eva [Stanford Univ., Stanford, CA (United States). SLAC and Dept. of Physics; California Univ., Santa Barbara, CA (United States). Kavli Inst. for Theoretical Physics; Westphal, Alexander [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Stanford Univ., Stanford, CA (United States). SLAC and Dept. of Physics
2010-11-15
We show how backreaction of the inflation potential energy on heavy scalar fields can flatten the inflationary potential, as the heavy fields adjust to their most energetically favorable configuration. This mechanism operates in previous UV-complete examples of axion monodromy inflation - flattening a would-be quadratic potential to one linear in the inflaton field - but occurs more generally, and we illustrate the effect with several examples. Special choices of compactification minimizing backreaction may realize chaotic inflation with a quadratic potential, but we argue that a flatter potential such as power-law inflation V({phi}){proportional_to} {phi}{sup p} with p<2 is a more generic option at sufficiently large values of {phi}. (orig.)
Simple exercises to flatten your potential
International Nuclear Information System (INIS)
Dong, Xi; Horn, Bart; Silverstein, Eva; California Univ., Santa Barbara, CA; Westphal, Alexander; Stanford Univ., Stanford, CA
2010-11-01
We show how backreaction of the inflation potential energy on heavy scalar fields can flatten the inflationary potential, as the heavy fields adjust to their most energetically favorable configuration. This mechanism operates in previous UV-complete examples of axion monodromy inflation - flattening a would-be quadratic potential to one linear in the inflaton field - but occurs more generally, and we illustrate the effect with several examples. Special choices of compactification minimizing backreaction may realize chaotic inflation with a quadratic potential, but we argue that a flatter potential such as power-law inflation V(φ)∝ φ p with p<2 is a more generic option at sufficiently large values of φ. (orig.)
Potential controlled flotation of Sarcheshmeh Molybdenite
International Nuclear Information System (INIS)
Kolahdoozan, M.; Noori, H.
2007-01-01
Molybdenite flotation in the Sarcheshmeh Copper Complex was studied as a function of pulp potential, controlled using two types of sodium sulfide, a mineral origin and a chemical nature. Air and either plant or laboratory nitrogen were used as flotation careers. Potential readings took place in rougher cells, as it was proved to be vital in the molybdenite circuit. Results showed that, at reducing potentials between -525 and -575 mv, the highest molybdenum recovery of 93% and the lowest copper recovery of 4-15% can be achieved. These potentials did not change considerably by adding extra amounts of sodium sulfide. At more oxidizing potentials, i.e. more than -450 mv, copper recovery increases while the recovery of Molybdenite drops
Canadian wind energy technical and market potential
International Nuclear Information System (INIS)
Templin, R.J.; Rangli, R.S.
1992-01-01
The current status of wind energy technology in Canada is reviewed, the technical potential of wind energy in Canada is estimated, and the economic market potential is assessed under several scenarios over about the next 25 years. The technical potential is seen to be large, with applications to water pumping on farms, the coupling of wind turbines to diesel-electric systems in remote communities where fuel costs are high, and the supply of electricity to main power grids. The main-grid application has greatest technical potential, but it cannot be economically exploited under the present utility buyback rate structure for intermittent power sources. A change in government policy toward market development of renewable energy sources, such as is already taking place in several European countries, would greatly increase market potential, decrease emissions of CO 2 and SO 2 , and benefit the Canadian wind energy industry. 2 figs., 1 tab
Critical potentials, leptons, and weak currents
International Nuclear Information System (INIS)
Smith, P.F.; Lewin, J.D.
1977-12-01
A theoretical study is made of the interaction of very strong localised electromagnetic potentials with charged leptons, and with the vacuum state. The principal objective is to investigate the phenomena which occur when the potential reaches or exceeds the critical value at which bound levels are drawn into the lower continuum. The behaviour of bound and continuum solutions of the Dirac equation for the specific model of a short range potential well in an arbitrarily large bounded volume is examined in detail. Vacuum polarisation effects are computed by summation over the infinite set of single particle levels, and special attention is given to the behaviour of the overall charge distribution as the potential strength increases through the critical value. The most significant features of the results are (a) the formation of highly localised electron or muon bound states, (b) similar critical potential strengths for electrons and muons, and (c) redefinition of the vacuum by one charge unit at the critical potential. These features are analogous to some properties of leptonic and hadronic weak currents, and the hypothesis is proposed that strong short range potentials may provide a possible mediating mechanism for the weak interaction and also a lepton confinement mechanism within the structure of hadrons. (author)
Chloride equilibrium potential in salamander cones
Directory of Open Access Journals (Sweden)
Bryson Eric J
2004-12-01
Full Text Available Abstract Background GABAergic inhibition and effects of intracellular chloride ions on calcium channel activity have been proposed to regulate neurotransmission from photoreceptors. To assess the impact of these and other chloride-dependent mechanisms on release from cones, the chloride equilibrium potential (ECl was determined in red-sensitive, large single cones from the tiger salamander retinal slice. Results Whole cell recordings were done using gramicidin perforated patch techniques to maintain endogenous Cl- levels. Membrane potentials were corrected for liquid junction potentials. Cone resting potentials were found to average -46 mV. To measure ECl, we applied long depolarizing steps to activate the calcium-activated chloride current (ICl(Ca and then determined the reversal potential for the current component that was inhibited by the Cl- channel blocker, niflumic acid. With this method, ECl was found to average -46 mV. In a complementary approach, we used a Cl-sensitive dye, MEQ, to measure the Cl- flux produced by depolarization with elevated concentrations of K+. The membrane potentials produced by the various high K+ solutions were measured in separate current clamp experiments. Consistent with electrophysiological experiments, MEQ fluorescence measurements indicated that ECl was below -36 mV. Conclusions The results of this study indicate that ECl is close to the dark resting potential. This will minimize the impact of chloride-dependent presynaptic mechanisms in cone terminals involving GABAa receptors, glutamate transporters and ICl(Ca.
Marketing potential of industrial companies of Ukraine
Directory of Open Access Journals (Sweden)
O.V. Oliynyk
2016-03-01
Full Text Available The article determines the essence of the marketing potential of the company as a part of improving the efficiency of the company’s activity forming a united mechanism along with industrial and financial subsystems. The components of the total potential of the company, the factors forming structure of the marketing potential of the company and the approaches to the evaluation of such a potential of the company are considered. It is determined that the marketing potential of the company integrates all the marketing resources, reserves and the possibility of their use, and the functioning as well as development of the system are subjected to the achievement of the main company’s goals. The differences in the interpretation of economic, market and marketing potential of the company are identified, although they are related to the subject of entrepreneurship, but they differ in their essence. The substantiation of the essence of marketing potential of the company, the development of an effective mechanism of its management with the possibility of evaluation will contribute to the maximum satisfaction of interests of information consumers’ groups, the formation of strategic directions of the activity, making management decisions at the micro level, the effective functioning in the internal and external markets.
Quaternionic potentials and CP-violation
International Nuclear Information System (INIS)
Nishi, Celso Chikahiro
2000-01-01
Full text follows: In the formulation of Quantum Mechanics by using a non-commutative ring of quaternions, we attempt to solve the Schroedinger equation with quaternionic potentials. Decay processes can easily be modeled by including complex imaginary potentials. Although, it could be explained as a transition between states under action of a perturbation. Purely imaginary quaternionic potentials can be used to describe CP-violation effects. The neutral kaon system, K 0 - K-bar 0 or K L - K S , represents an example of CP-violation phenomenon. The inclusion of quaternionic potentials imply a reformulation of the whole quantum theory. The use of a quaternionic algebra in discussing the Schroedinger equation leads to the lost of time reversal invariance (T), closely connected to CP violation by the well-known CPT theorem. In particular, we study the Schroedinger equation in presence of a quaternionic potential barrier given in terms of V, real potential acting in the region of width a, and jW, purely quaternionic potential acting in the region of width b. Different cases, |W|/V and b/a, are discussed in view of possible deviations of standard Quantum Mechanics. The complex linear Schroedinger equation is solved for stationary states. The explicit solution contains complex and quaternionic transmission/reflection coefficients. A wave packet treatment needs to make a more realistic and physical description. We briefly discuss possible interpretations and remaining questions. (author)
Potential of renewable and alternative energy sources
Konovalov, V.; Pogharnitskaya, O.; Rostovshchikova, A.; Matveenko, I.
2015-11-01
The article deals with application potential of clean alternative renewable energy sources. By means of system analysis the forecast for consumption of electrical energy in Tomsk Oblast as well as main energy sources of existing energy system have been studied up to 2018. Engineering potential of renewable and alternative energy sources is evaluated. Besides, ranking in the order of their efficiency descending is performed. It is concluded that Tomsk Oblast has high potential of alternative and renewable energy sources, among which the most promising development perspective is implementation of gasification stations to save fuel consumed by diesel power stations as well as building wind-power plants.
Jacobi algebra and potentials generated by it
International Nuclear Information System (INIS)
Lutsenko, I.M.
1993-01-01
It is shown that the Jacobi algebra QJ(3) generates potentials that admit exact solution in relativistic and nonrelativistic quantum mechanics. Being a spectrum-generating dynamic symmetry algebra and possessing the ladder property, QJ(3) makes it possible to find the wave functions in the coordinate representation. The exactly solvable potentials specified in explicit form are regarded as a special case of a larger class of exactly solvable potentials specified implicitly. The connection between classical and quantum problems possessing exact solutions is obtained by means of QJ(3). 13 refs
Wave Energy Potential in the Latvian EEZ
Beriņš, J.; Beriņš, J.; Kalnačs, J.; Kalnačs, A.
2016-06-01
The present article deals with one of the alternative forms of energy - sea wave energy potential in the Latvian Exclusice Economic Zone (EEZ). Results have been achieved using a new method - VEVPP. Calculations have been performed using the data on wave parameters over the past five years (2010-2014). We have also considered wave energy potential in the Gulf of Riga. The conclusions have been drawn on the recommended methodology for the sea wave potential and power calculations for wave-power plant pre-design stage.
Model potential for electron scattering from rubidium
Energy Technology Data Exchange (ETDEWEB)
Gien, T.E. (Memorial Univ. of Newfoundland, St. John' s, NF (Canada). Dept. of Physics)
1992-11-28
An analytic model potential for the e[sup -]-Rb[sup +] system is generated from experimental data, using an iteration method. The potential obtained can reproduce rather accurately the energy levels of rubidium. We employed it in the calculation of elastic differential cross sections for electron (and positron) scatterings from rubidium in the conventional Glauber approximation. The differential cross sections calculated in the model potential approach are compared to those in the frozen-core approach, employing either the Clementi-Roetti or the Szasz-McGinn wavefunctions. The core correlation and polarization effects are found to significantly affect the cross section results. (author).
Model potential for electron scattering from rubidium
International Nuclear Information System (INIS)
Gien, T.E.
1992-01-01
An analytic model potential for the e - -Rb + system is generated from experimental data, using an iteration method. The potential obtained can reproduce rather accurately the energy levels of rubidium. We employed it in the calculation of elastic differential cross sections for electron (and positron) scatterings from rubidium in the conventional Glauber approximation. The differential cross sections calculated in the model potential approach are compared to those in the frozen-core approach, employing either the Clementi-Roetti or the Szasz-McGinn wavefunctions. The core correlation and polarization effects are found to significantly affect the cross section results. (author)
Interaction potential for two different atoms
International Nuclear Information System (INIS)
Kuzmichev, V.E.; Peresypkin, V.V.
1991-01-01
Using the rigorous approach to the nonrelativistic four Coulomb particle problem the interaction potentials between an ordinary hydrogen and muonic-hydrogen atoms at large: R>a e +a μ (1), and intermediate: a e >R>>a μ (2) distances, where a e and a μ are the Bohr radii, are calculated in the adiabatic approximation. The van der Waals potential constants in the region (1) and an explicit potential form in the region (2) taking into account both the polarization effects and the electron screening corrections are determined. 10 refs
The tachyon potential in string theory
International Nuclear Information System (INIS)
Banks, T.
1991-01-01
We argue that the tachyon potential in string theory is exactly given by the unstable quadratic mass term calculated perturbatively around the critical string. The argument is given in terms of the sigma model formulation. The same result follows from the exact Wilson renormalization group equations. The discrepancy with previous calculations of the tachyon potential is explained by the fact that other authors worked near the tachyon mass shell where it is impossible to distinguish a potential from derivative terms in the effective action. (orig.)
International Nuclear Information System (INIS)
Petrascu, M.; Bordeanu, C.; Isbasescu, A.; Mihai, I.; Giurgiu, M.
1997-01-01
Recently, an inclusive fusion experiment of 9,11 Li projectiles with Si targets, in the energy range (9.5 - 25) AMeV has been performed at Riken Ring Cyclotron-Japan using, for the detection of the fusion products, an ionization chamber, MUSIC, built in NIPNE-HH, Bucharest. In this experiment, the contribution of elastic and inelastic scattering, at forward detection angles is eliminated through the experimental set-up. For a clear investigation of the fusion process, the estimation of elastic and inelastic scattering at backward angles, between 80 angle - 180 angle was considered necessary. This estimation was made by the coupled channels computer code ECIS. ECIS is an iterative method, the first iteration of this procedure being DWBA. In the analysis of elastic and inelastic scattering of 9,11 Li projectile on Si target we assumed that the incident 9 Li and 11 Li waves are diffracted by an optical potential with an Woods-Saxon geometry. The adopted optical potential is given. For the depth of the real and imaginary volume terms we used values dependent on projectile energy and target mass number. These values have been chosen in good agreement with a semi-microscopic model with a double-folding potential. The set of optical parameters selected for the system 9,11 Li (13 AMeV) + Si is given. The presence of neutron halo of 11 Li nucleus was taken into account by using adjusted values for the parameters r R and a R . The 28 Si nucleus is considered a rigid rotor, including the couplings involving the ground state and a first to excited states. The quadrupole deformation parameter was β 2 = - 0.24. The results for the scattering of 11 Li projectile on Si target at 13 AMeV energy are given with the parameters R match , I and J max taken from the Monte Carlo simulations with PACE code. We found that the contribution of elastic and inelastic scattering for background angles, between 80 angle - 180 angle is under 2%. The contribution of a inelastic scattering taken
Momentum distribution of nucleons at the second minimum of the fission path
International Nuclear Information System (INIS)
Mesa, J.; Arruda-Neto, J. D. T.; Rodrigues, T. E; Garcia, C. E.; Rodriguez, O.; Guzman, F.; Garcia, F.
2007-01-01
The momentum distribution (MD) of nucleons in a nucleus is an important issue ( for analyzing single-particle aspects of nuclear structure, for a review see [1]). One of the still open problems is the influence of global nuclear deformation on MD. There already exist some studies on that subject, see, e.g. [2,3] and references therein. Nonetheless, the present knowledge about deformation effects in MD is still rather poor, especially in heavy deformed nuclei. At the same time, these effects can be essential for a correct treatment of knock-out reactions, such as (e; e'p), in rare earth and actinide regions and for investigation of deep hole states in deformed nuclei (see, e.g., [4,5]). In our work we analyze momentum distributions of neutrons in odd plutonium isotopes at second minimum deformations in the framework of the phenomenological deformed Woods-Saxon potential. The shell correction and macroscopic part of the potential energy have been calculated via the Macroscopic-Microscopic formalism [6], considering as main deformation parameters ε (elongation) and α4 (hexadecapolar momentum) in Pashkevich's nuclear shape parametrization [6,7]. The parameters for the nuclear potential in the equilibrium deformations as well as in the second minimum were taken from a previous work [7]. References [1] A. N. Antonov, P. E. Hodgson and I. Zh. Petkov Nucleon Correlations in Nuclei (Berlin: Springer) 1993 [2] E. Moya de Guerra, J. A.Caballero and P. Sarriguren, Nucl. Phys. A 477 445 (1988). [3] V. O. Nesterenko, V. P. Likhachev, P.-G. Reinhard, V. V. Pashkevich, W. Kleinig, J. Mesa, Phys. Rev. C 70, 057304 (2004) [4]V. P. Likhachev, J. Mesa, J. D. T. Arruda-Neto, et al., Phys. Rev. C 65 044611 (2002). [5] V. P. Likhachev, J. Mesa, J. D. T. Arruda-Neto, et al., Nucl. Phys. A 713, 24 (2003). [6] F. Garcia, O. Rodriguez, J. Mesa, et al., Comput. Phys. Commun. 120 , 57 (1999). [7] F. Garcia, E. Garrote, M.-L. Yoneama, J. D. T. Arruda-Neto, J. Mesa, et al., Eur. Phys. J. A 6
Energy Technology Data Exchange (ETDEWEB)
García-Ravelo, J., E-mail: g.ravelo@hotmail.com [Departamento de Física, Escuela Superior de Física y Matemáticas, Instituto Politécnico Nacional, Edificio 9, Unidad Profesional Adolfo López Mateos, México D.F., 07738 (Mexico); Menéndez, A.; García-Martínez, J. [Departamento de Física, Escuela Superior de Física y Matemáticas, Instituto Politécnico Nacional, Edificio 9, Unidad Profesional Adolfo López Mateos, México D.F., 07738 (Mexico); Schulze-Halberg, A. [Department of Mathematics and Actuarial Science and Department of Physics, Indiana University Northwest, 3400 Broadway, Gary, IN 46408 (United States)
2014-06-13
We show that the effective Kratzer and Coulomb potentials can be obtained by taking particular limits of a multiparameter exponential potential that was studied recently. Moreover, we demonstrate that the bound state solutions of the exponential potential reduce correctly to their well-known counterparts associated with the Kratzer and Coulomb potentials. As a byproduct, we obtain a new limit relation for the hypergeometric function. - Highlights: • Kratzer and Coulomb potentials are limit cases of an exponential-type potential. • From exact s-waves, approximate solutions for l-waves are obtained. • l-waves of the potential tend to the solutions of the Kratzer and Coulomb potentials. • A non-evident identity between hypergeometric functions is demonstrated.
International Nuclear Information System (INIS)
García-Ravelo, J.; Menéndez, A.; García-Martínez, J.; Schulze-Halberg, A.
2014-01-01
We show that the effective Kratzer and Coulomb potentials can be obtained by taking particular limits of a multiparameter exponential potential that was studied recently. Moreover, we demonstrate that the bound state solutions of the exponential potential reduce correctly to their well-known counterparts associated with the Kratzer and Coulomb potentials. As a byproduct, we obtain a new limit relation for the hypergeometric function. - Highlights: • Kratzer and Coulomb potentials are limit cases of an exponential-type potential. • From exact s-waves, approximate solutions for l-waves are obtained. • l-waves of the potential tend to the solutions of the Kratzer and Coulomb potentials. • A non-evident identity between hypergeometric functions is demonstrated
Unintended Positional Drift and Its Potential Solutions
DEFF Research Database (Denmark)
Nilsson, Niels Christian; Serafin, Stefania; Nordahl, Rolf
2013-01-01
many users unintentionally move forward while walking in place. We refer to this phenomenon accidental movement as Unintended Positional Drift. The poster presents evidence of the phenomenon's existence and subsequently discusses different design solutions which potentially could circumvent the problem....
Ozone-forming potential of reformulated gasoline
National Research Council Canada - National Science Library
Committee on Ozone-Forming Potential of Reformulated Gasoline, National Research Council
... and comparison of the emissions from motor vehicles using different reformulated gasolines based on their ozone-forming potentials and to assess the concomitant impact of that approach on air-quality benefits...
Potential organ donor audit in Ireland.
LENUS (Irish Health Repository)
Hegarty, M
2010-11-01
As increasing demand for organs is a challenge for transplant services worldwide it is essential to audit the process of organ donation. To address this, a national audit of potential organ donors was undertaken across hospitals with Intensive Care Units (N = 36). Questionnaires were returned on all patients (n = 2073) who died in these units from 1\\/9\\/07-31\\/8\\/08; 200 (10%) of these patients were considered for Brain Stem Testing (BST), 158 patients (79%) were diagnosed Brain Stem Dead (BSD) and 138 patients (87%) became potential donors. Consent for donation was given by 92 (69%) next of kin and 90 potential donors (65%) became organ donors. There was no evidence of a large number of potential organ donors being missed. Recommendations included completion of BSTs on all appropriate patients, development of support on BST, referral of all BSD patients to the Organ Procurement Service; enhanced co-ordination within hospitals and sustained information\\/education campaigns.
Effective potentials in gauge field theories
International Nuclear Information System (INIS)
Caldas, P.S.S.; Fleming, H.; Garcia, R.L.
An elementary and very efficient method for computing the effective potential of any theory containing scalar bosons is described. Examples include massless scalar electrodynamics and Yang-Mills theories [pt
Potential targets for lung squamous cell carcinoma
Researchers have identified potential therapeutic targets in lung squamous cell carcinoma, the second most common form of lung cancer. The Cancer Genome Atlas (TCGA) Research Network study comprehensively characterized the lung squamous cell carcinoma gen
Potential in stochastic differential equations: novel construction
International Nuclear Information System (INIS)
Ao, P
2004-01-01
There is a whole range of emergent phenomena in a complex network such as robustness, adaptiveness, multiple-equilibrium, hysteresis, oscillation and feedback. Those non-equilibrium behaviours can often be described by a set of stochastic differential equations. One persistent important question is the existence of a potential function. Here we demonstrate that a dynamical structure built into stochastic differential equation allows us to construct such a global optimization potential function. We present an explicit construction procedure to obtain the potential and relevant quantities. In the procedure no reference to the Fokker-Planck equation is needed. The availability of the potential suggests that powerful statistical mechanics tools can be used in nonequilibrium situations. (letter to the editor)