bluuebunny/crossref_metadata_2025_split huggingface dataset:
Pulse Power Compression by Cutting a Dense Z-Pinch with a Laser Beam
Authors: Winterberg F. 
Published: February 2015

Abstract
A thin cut made through a z-pinch by an intense laser beam can become a magnetically insulated diode crossed by an intense ion beam. For larger cuts, the gap is crossed by an intense relativistic electron beam, stopped by magnetic bremsstrahlung resulting in a pointlike intense x-ray source. In either case, the impedance of the pinch discharge is increased, with the power delivered rising in the same pro-portion. A magnetically insulated cut is advantageous for three reasons: First, with the ion current com-parable to the Alfvèn ion current, the pinch instabilities are reduced. Second, with the energy deposit-ed into fast ions, a non-Maxwellian velocity distribution is established increasing〈σ ν〉 value for nuclear fusion reactions taking place in the pinch discharge. Third, in a high density z-pinch plasma, the intense ion beam can launch a thermonuclear detonation wave propagating along the pinch discharge channel. For larger cuts the soft x-rays produced by magnetic bremsstrahlung can be used to drive a thermonuclear hohlraum target. Finally, the proposed pulse power compression scheme permits to use a cheap low power d.c. source charging a magnetic storage coil delivering the magnetically stored energy to the pinch discharge load by an exploding wire opening switch.
Darkness Intensified -Existence of a Nonlinear Threshold in Redshift-Induced Dimming
Authors: Rössler O. E. 
Published: February 2015

Abstract
Redshift obeys adiabatic invariance. From this fact it follows that not only the individual photons are dimmed by a factor of z + 1 (if z is the redshift in percent), but the photon flux is reduced by the same factor once more. Hence the luminosity of any source is in the presence of redshift dimmed by a factor of (z+1)2. This model-independent result possibly “explains away” the excess dimming of strongly redshifted Type-la super-novae, discovered in 1998.
Structure and Vibrational Spectra of the Vapour Molecules Fe2Cl6 and AlFeCl6
Authors: Akdeniz Z. , Tosi M. P. 
Published: February 2015

54a,
Melting of aluminium and iron trichloride crystals is accompanied by a structural transition from octahedral to tetrahedral coordination of the metal ions, and a widely accepted interpretation of their liquid structure is that it mainly consists of strongly correlated dimeric units. Such Al2Cl6 and Fe2Cl6 molecules are stable in the vapour phase and coexist in gaseous mixtures together with AlFeCl6 molecules. In this work we extend to Fe2Cl6 and AlFeCl6 our earlier study of the ionic interactions in Al2Cl6 [Z. Akdeniz and M. P. Tosi, Z. Naturforsch. 180 (1999)], using a model which accounts for ionic deformability through (i) effective valences and (ii) electrostatic and overlap polarizabilities. The main disposable parameters of the model are adjusted to the Fe-Cl bond length in FeCl3 monomer molecule and to the Fe-Fe bond length and a bond-stretching frequency in the Fe2Cl6 molecule. The results are used to evaluate the structure of the AlFeCl6 molecule, which has so far only been inferred from the observed Raman spectrum in mixed vapours. Extensive comparisons with data on molecular vibrational frequencies are also presented for Fe2Cl6 and AlFeCl6.
High Resolution Infrared Detection of O=PF in the Gas Phase
Authors: Paplewski P. , Bürger H. , Beckers H. 
Published: February 2015

Short-lived phosphenous fluoride, 0=PF, has been made by flash pyrolysis of F2POPF2 in Ar at 1200°C and detected by gas phase IR spectroscopy. The υ1 band, υ0 = 1297.5372 cm-1 , has been studied with a resolution of 8 x 10-3 cm-1 , and about 1500 transitions have been assigned. These were fitted using a Watson-type Hamiltonian, σ = 1.5 x 10-3 cm-1 , to excited state parameters up to quartic centrifugal distortion constants. The υ2 band was located at 819.58 cm-1 . An extended set of ground state parameters was obtained by combining recently measured microwave transitions with ground state combination differences formed from υ1 transitions.
The experimental results are in perfect agreement with the matrix IR spectra, mw measurements and ab initio calculations but disagree with a recently claimed low resolution detection of OPF in the gas phase.
Electrochemical Impedance Spectroscopic Study on Eu 2+ and Sr 2+ Using Liquid Metal Cathodes in Molten Chlorides
Authors: Matsumiya Masahiko , Takagi Ryuzo 
Published: February 2015

Abstract
For the pyrochemical reprocessing of spent metallic nuclear fuels in molten salt baths it is important to investigate the behavior of the electrochemically negative elements Eu and Sr, which are significant fission products. Voltammetric and chronopotentiometric studies have shown that the reduction of Eu 2+ and Sr 2+ on liquid Pb cathodes in molten chloride baths at 1073 K follows the alloy formation reaction: Eu 2+ + 2e− + 3Pb → EuPb 3 and Sr 2+ + 2e− + 3Pb → SrPb 3 . In the present work these alloy formation reactions were studiedby electrochemical impedance spectroscopy. Analysis of the spectra showed that the electronic exchange of Eu 2+ /Eu and Sr 2+ /Sr is quasi-re-versible. Moreover, the experimental results allowed the determination of the kinetic parameters of EU 2+ /EU and Sr 2+ /Sr, the diffusion coefficients of these species in molten chloride baths, and also the diffusion layer thickness.
Dynamic Nuclear Polarization Studies of TANOL/water-glycerol Solutions
Authors: Sert İsmail , Sünnetçioǧlu M. Maral , Sungur Rıza , Bingöl Gökçe 
Published: February 2015

Abstract
Dynamic Nuclear Polarization (DNP) studies of TANOL/water-glycerol solutions were per-formed at 1.53 mT. The samples have either various water-glycerol ratios at constant concentration or various concentrations at a constant water-glycerol ratio. The low field EPR spectra were recorded, the DNP parameters(enhancement factors, coupling constant, leakage factor) were determined, electronic relaxation times were measured. Depending on the values obtained, the interactions between nuclei and electrons are discussed.
Molecular Motion and Crystal Structure of Solid Tetrapentylammonium Iodide
Authors: Szafrańska B. , Małuszyńska H. , Pająk Z. 
Published: February 2015

Abstract
The proton NMR spectra and spin-lattice relaxation times of tetrapentylammonium iodide have been measured between 100 K and the melting point. The room temperature crystal structure has been determined by X-ray diffraction as orthorhombic, space group Ccca, Z = 4 with a = 10.811(2), b = 22.771(5) and c = 9.500(2) Å with fully ordered tetrapentylammonium cations. The existence of a solid-solid phase transition at 400 K has been confirmed by DTA. The onset of C 3 methyl group reorientations characterized by Arrhenius activation parameters has been evidenced. The intracation conformational motions in the pentyl chains start to manifest themselves already at lower temperatures. The appearence of an ionic plastic phase with coexisting liquid-like and solid-like cations has been discovered.
Effect of Substituent on Crystal Structures of N-(Substituted- phenyl)-2,2,2-Trichloroacetamides, 2/3/4-XC 6 H 4 .NHCO.CCl 3 (X = Cl, NO 2 or CH 3 )
Authors: Thimme Gowda B. , Paulus Helmut , Fuess Hartmut 
Published: February 2015

Abstract
The crystal structures of N-(substitutedphenyl)-2,2,2-trichloroacetamides of the type 2/3/4-
XC6H4.NHCO.CCl3 (X = CI, NO2 or CH3), namely, N-(3-nitrophenyl)-2,2,2-trichloroacetamide,
3-NO2C6H4.NHCO.CCl3 (m-NO2PhTCA); N-(4-nitrophenyl)-2,2,2-trichloroacetamide,
4-NO2C6H4.NHCO.CCl3 (p-NO2PhTCA); N-(2-chlorophenyl)-2,2,2-trichloroacetamide,
2-ClC6H4.NHCO.CCl3 (o-ClPhTCA) and N-(4-chlorophenyl)-2,2,2-trichloroacetamide, 4-
C1C6H4.NHCO.CCl3 (p-ClPhTCA) have been determined at room temperature. The present
data are analysed along with our earlier crystal structures of N-(2-nitrophenyl)-2,2,2-trichloroacetamide,
2-NO2C6H4.NHCO.CCl3 (o-NO2PhTCA); N-(4-methylphenyl)-2,2,2-trichloroacetamide,
4-CH3C6H4. NHCO.CCl3 (p-CH3PhTCA); N-(phenyl)-2,2,2-trichloroacetamide,
C6H5.NHCO.CCl3 (PhTCA); N-chloro-N-(phenyl)-2,2,2-trichloroacetamide, C6H5.NClCO.CCl3

(NClPhTCA); and finally with N-(phenyl) acetamide, C6H5.NHCO.CH3 (PhA). The crystal type,
space group, formula units and lattice constants in Å of the new structures are; m-NO2PhTCA:
triclinic, PI, Z = 4, a = 7.493(3), b = 9.992(3), c = 15.225(5), α = 84.16(2)°, β = 82.59(2)°, γ =
84.92(2); p-N02PhTCA: monoclinic, P21/n, Z = 4, a = 5.807(2), b = 15.354(6), c = 12.475(5),
β = 92.28(2)°; o-ClPhTCA: orthorhombic, Pna21, Z = 4, a = 8.769(2), b = 12.838(3), c = 9.578(2)
and p-ClPhTCA: orthorhombic, Pbca, Z = 8, a = 9.742(4), b = 10.031(4), c = 23.110(9). The
compounds, m-NO2PhTCA, o-NO2PhTCA and p-CH3PhTCA show two molecules each in their
asymmetric units. This is in agreement with the multiple lines observed in the 35Cl NQR spectra
of the latter two compounds. But the presence of two molecules in the asymmetric unit of m-
NO2PhTCA indicates that it may undergoe a phase transition below room temperature. The bond
lengths and bond angles are normal except for some deviations. The presence of strong electron
withdrawing group at the ortho position of the phenyl ring and N-chlorination of the amide will
have significant effect on some bond distances and bond angles.
Study of High Frequency Relaxation Processes in Three Substances with the -CN Groups at the Lateral Positions
Authors: Urban Stanisław , Gestbloma Bo , Dąbrowskib Roman , Dziaduszekb Jerzy 
Published: February 2015

Abstract
Three liquid crystalline (LC) substances with the cyano-groups attached at the lateral positions to the molecular cores were studied with the aid of dielectric spectroscopy methods. The high frequency relaxation process connected with the molecular reorientations around the long molecular axes was studied in the isotropic, nematic and several smectic phases. The dielectric spectra are rather complex, indicating a contribution from several molecular processes to the main relaxation process. The dielectric time changes smoothly at the phase transitions between "liquid-like" phases (isotropic -nematic -smectic A -smectic C), and becomes shorter at the transition to the "solid-like" smectic G phase with a low-ering of the activation barrier. This indicates that the molecules perform broad angle librational motions rather than overall rotational motions in this phase. In case of a substance having two cyano groups at-tached to the benzene ring, a pronounced jump-wise change of the relaxation time was observed at the isotropic -smectic A transition.
Luminescence Properties of Some Coumarins with 3:4-Fused Ring System
Authors: Nikolov Peter , Petkova Ivan , Markov Peter 
Published: February 2015

Abstract
The photophysical characteristics of a group of coumarins with a 3:4-fused ring system (2-substitut-ed-4,5-dioxo-l,2-dihydro-4H,5H-pyrano-[3:4-c] [1]-benzopyrans) in solutions at room temperature, in frozen ethanol matrix at 77 K, in solid phase and in PVC films are reported. The low fluorescence quan-tum yield of the compounds investigated in solution is explained as a result of internal conversion from the fluorescent S2 (ππ*) state to the lower lying S1(nπ*) state. The phosphorescence with a life time in the order of seconds is connected with intersystem crossing S1 (nπ*) -T1(ππ*). The absorption Franck Condon transitions in solid phase and in PVC matrix are only weekly batochromically shifted accord-ing to solution.
Structure and Energetics of Clusters Relevant to Thorium Tetrachloride Melts
Authors: Akdeniz Z. , Tosi M. P. 
Published: February 2015

Abstract
We study within an ionic model the structure and energetics of neutral and charged molecular clusters which may be relevant to molten ThCl4 and to its liquid mixtures with alkali chlorides, with reference to Raman scattering experiments by Photiadis and Papatheodorou. As stressed by these authors, the most striking facts for ThCl4 in comparison to other tetrachloride compounds (and in particular to ZrCl4) are the appreciable ionic conductivity of the pure melt and the continuous structural changes which occur in the melt mixtures with varying composition. After adjusting our model to data on the isolated ThCl4 tetrahedral molecule, we evaluate (i) the Th2Cl8 dimer and the singly charged species obtained from it by chlorine-ion transfer between two such neutral dimers; (ii) the ThCl6 and ThCl7 clusters both as charged anions and as alkali-compensated species; and (iii) various oligomers carrying positive or negative double charges. Our study shows that the characteristic structural properties of the ThCl4 compound and of the alkali-Th chloride systems are the consequence of the relatively high ionic character of the binding, which is already evident in the isolated ThCl4 monomer.
Ground and Excited State Dipole Moments of LAURDAN Determined from Solvatochromic and Thermochromic Shifts of Absorption and Fluorescence Spectra
Authors: Kawski A. , Kukliński B. , Bojarski P. , Diehl H. 
Published: February 2015

Abstract
The electric dipole moments in the ground /µg and excited state of the fluorescent probe LAUR-DAN are determined from solvatochromic and thermochromic shifts to be /µg = 3.46 D, µe = 10.6 D and /µg = 3.76 D, /µe = 10.24 D, respectively. These values concern the free LAURDAN molecule. The val-ues of the dipole moments of LAURDAN (= 6-decanoyl-2-dimethylamine-naphthalene) exceed dis-tinctly those of PRODAN (= 6-propionyl-2-dimethylamine-naphthalene).
PVT Measurements on 3-Cyanobenzyl 2,5-bis(4-n-octyloxybenzoyl- oxy)benzoate up to 250 MPa and 423 K
Authors: Würflinger A. , Sandmann M. , Weissflog W. 
Published: February 2015

Abstract
P, Vm , T data have been measured for the nematic and isotropic phases of 3-cyanobenzyl 2,5-bis (4-n-octyloxybenzoyloxy)benzoate between 273 and 423 K and up to 250 MPa. The volume changes accompanying the crystal -nematic and nematic -isotropic transitions have been determined. The cor-responding enthalpy changes have been calculated using the Clausius-Clapeyron equation. The p, V m , T data enable also to estimate the volume entropy for the nematic-isotropic transition. It is found that the configurational part of the transition entropy amounts to 80%, this portion being distinctly larger than found in previous studies for conventional rod-like liquid crystals.
Photoisomerization of Triazine-stilbene Fluorescent Brighteners in Solution and in their Copolymers with Styrene
Authors: Grabchev Ivo , Bojinov Vladimir 
Published: February 2015

Abstract
The paper reports on the photochemical trans-cis isomerization of some new polymerizable triazine-stilbene fluorescent brighteners and their copolymers with styrene in aqueous and ethanol solutions. A dependence of trans-cis isomers in solution equilibrium and in solid polymeric films on the nature of the substituent in the triazine ring has been found.
Mean Amplitudes of Vibration of the Tetrafluorophosphite, PF4
−, Anion
Authors: Baran E. J. 
Published: February 2015

Abstract
Mean amplitudes of vibration of the pseudo-trigonal bipyra-midal PF4
−anion have been calculated from vibrational spectroscopic data in the temperature range between 0 and 1000 K. The results are briefly discussed in relation to the structural peculiarities of the anion and some comparisons with related species are made.
Comment on the Comment by G. Schäfer on the Paper "Non-kinematicity of the Dilation-of-time Relation of Einstein for Time-intervals" by S. Golden
Authors: Jefimenko O. D. 
Published: February 2015

Abstract
In his comment G. Schäfer [1] points out that S. Golden's [2] time-dilation equations (12) and (13) are of kinematic type and that the title of Golden's paper is therefore a misconception. He also states that Golden's treatment of the time-dilation problem is incomplete, since Golden has not considered particle decay in his paper. I should like to present my comment on these two points raised by G. Schäfer. Although Golden describes his equation (13) as "spatially dependent," he says at the beginning of Sect. 4 of his paper that his equations (12) and (13) can be regarded as "either velocity dependent or spatially dependent." But this is not at all the essence of his paper. The essence of his paper is that the two time-dilation equations that he has derived do not imply "any actual dilation-of-time in clocks that may be stationed in the systems." Hence he concludes that Einstein's time-dilation relation is merely a transformation relation and that the motion of the systems does not affect "the intrinsic time-rates of any clocks stationed within them." In order to judge the significance of Golden's paper, it is important to remember that Einstein arrived at the ideas of kinematic time-dilation and length contraction in moving systems not as a result of a rigorous deduction from any mathematical, physical or logical relations, but simply by interpreting in his own way the physical significance of transformation equations for space and time (Lorentz transformation equations) [3]. Ever since the publication of his 1905 article, Einstein's ideas of kinematic length contraction and time dilation
Sending Signals to Space-Like Separated Regions
Authors: Aharonov Y. , Vaidman L. 
Published: February 2015

Abstract
Two recent works suggest a possibility of sending signals to a space-like separated region, contrary to the spirit of special relativity. In the first work (J. Grunhaus, S. Popescu, and D. Rohrlich, Phys. Rev. A 53, 3781 (1996)) it has been shown that sending signals to a particular union of space-like separated regions cannot cause causality paradoxes. Another work (Y. Aharonov and L. Vaidman, Phys. Rev. A 61, 052108 (2000)) showed that the relative phase of the quantum superposition of a particle at two separate locations can be measured locally. Together with the possibility of changing the relative phase in a nonlocal way using the potential effect we, apparently, have a method of sending signals to space-like separated regions. These arguments are critically analyzed in this paper.
Young's Experiment, Schrödinger's Spread and Spontaneous Intrinsic Decoherence
Authors: Bonifacio R. , Olivares S. 
Published: February 2015

Abstract
The two slits interference pattern for single particle is revisited, showing its strict relation to the free particle Schrödinger’s spread and describing the optical analogy. We explicitly show the possibility that spontaneous intrinsic decoherence (SID) can destroy interference pattern and that decoherence becomes stronger at the macroscopic limit.
Quantum Physics and Reality
Authors: Haag Rudolf 
Published: February 2015

Abstract
Apparent paradoxes in Quantum Physics demand a sharp distinction between a "real part of the world" and the realm of possibilities. In the former we may distinguish individual elements (coarse events) relating to space-time, with causal connections between them respecting the relativistic locality principle. The latter, quantitatively described by probability assignments conditioned on existing facts and depending on the definition of equivalence classes of situations, cannot be subdivided in space-time categories. There are global correlations (Pauli principle...). The cut between the realms of facts and possibilities implies an evolutionary picture of the "real world" in which the (generalized) arrow of time assumes basic significance. Some deficiencies of existing theory are pointed out.
The Paradoxes of the Interaction-free Measurements
Authors: Vaidman L. 
Published: February 2015

Abstract
Interaction-free measurements introduced by Elitzur and Vaidman [Found. Phys. 23,987 (1993)] allow finding infinitely fragile objects without destroying them. Paradoxical features of these and related measurements are discussed. The resolution of the paradoxes in the framework of the Many-Worlds Interpretation is proposed.
Interaction-Free Which-Path Information and Some of Its Consequences
Authors: Ryff Luiz Carlos 
Published: February 2015

Abstract
Let us consider a single particle in an interferometer. If one of the two possible paths is blocked and the particle is detected, we know that the particle has followed the path which is not blocked. This would be an interference-free "which-path" information experiment. However, we no longer have an interfe­rometer, since one path is blocked. An alternative is to interact with the particle, but this would change its momentum and as a consequence the interference fringes would disappear, as discussed by Feynman. We can also consider two particles entangled in direction. Knowing the path followed by one of the par­ticles, it is possible to know the path followed by the other. On the other hand, when this information is erased, interference can be observed. However, this is a two particle interference: no single particle inter­ference can be observed. Retrodiction experiments are also possible, but these are not conclusive. Here we propose a much less intuitive experiment in which, without blocking one path or directly interacting with the particle, it is possible to know the path which is being followed by the particle in the interferom­eter. According to quantum mechanics, this is sufficient to lose the single particle interference. The same idea can be used to test the local pilot wave interpretation, to test quantum nonlocality under new conditions, and to devise an interferometer for a two-photon wave packet. This last result strongly suggests that there must be some connection between the deBroglie wavelength of an N-particle wave packet and entanglement. Wavelength of an /V-particle Wave Packet.
Non-Collinear Configuration for Dichromatic Squeezing
Authors: Andreoni Alessandra , Bondani Maria , D ’Ariano G. Mauro , Paris Matteo G. A. 
Published: February 2015

Abstract
We propose a non-collinear experimental scheme for the joint generation of two amplitudesqueezed beams at the frequencies u\ and u>2, fundamental and second harmonics of a Nd:YAG laser pulse. The scheme consists of two successive steps, both involving second-order non-linear interactions in ß - BaB2O4 non-linear crystals. One of the output beams show subPoissonian photon statistics, and this allows to use photodetection instead of homodyne detection for diagnostics
Nonlocal de Broglie Wavelength of a Two-Photon System
Authors: Fonseca E. J. S. , Paulinia Zoltan , Nussenzveig P. , Monkena C. H. , Padua S. 
Published: February 2015

Abstract
We show that it is possible to associate a de Broglie wavelength to a composite system even when the constituent particles are separated spatially. The nonlocal de Broglie wavelength (A /2) of a two-photon system separated spatially is measured with an appropriate detection system. The two-photon system is prepared in an entangled state in space-momentum variables. - Pacs: 42.50.-p, 42.50.Ar
Flopping between Schrödinger's Cat States
Authors: Frasca Marco 
Published: February 2015

Abstract
We show that for an atom in a cavity in the strong coupling regime, flopping between Schrödinger cat states, devised as a superposition of displaced number states, can be accomplished. Beside, the Rabi frequency can be set to zero, so that population trapping or localization can be accomplished. These states could be proved to be useful for quantum computation
Bohm's Mysterious 'Quantum Force' and 'Active Information': Alternative Interpretation and Statistical Properties
Authors: Lan Boon Leong 
Published: February 2015

Abstract
An alternative interpretation to Bohm’s ‘quantum force’ and ‘active information’ is proposed. Numerical evidence is presented, which suggests that the time series of Bohm’s ‘quantum force’ evaluated at the Bohmian position for non-stationary quantum states are typically non-Gaussian stable distributed with a flat power spectrum in classically chaotic Hamitonian systems. An important implication of these statistical properties is briefly mentioned
Decoherence and Universality of a Quantum Phase Gate
Authors: Mancini Stefano , Bonifacio Rodolfo 
Published: February 2015

Abstract
We study the dephasing noisy effects on a Quantum Phase Gate and the consequences on its universality. To this end we employ two frameworks displaying their differences and analogies. Pacs: 03.67.Lx, 03.65.Bz