Volume 57, Number 7-8, 2012
Theoretical Physics
Shock Wave Solution of Benney-Luke Equation Houria Triki, Ahmet Yildirim, T. Hayat, Omar M. Aldossary, Anjan Biswas Romanian Journal of Physics 57,
1029-1034 (2012)
This paper obtains the shock wave solution, also known as topological 1-soliton solution, of the Benney-Luke equation. The ansatz method is going to be used to integrate the equation for the solution. The parameter restrictions will also fall out naturally in course of derivation of the solution.
A Note on Wave Packets Broadening in a Fuzzy Spacetime Kourosh Nozari, Y. Namaki-Ravesh Romanian Journal of Physics 57,
1035-1045 (2012)
We study propagation of a Gaussian wave packet in a spacetime with a minimal observable length and a maximal observable momentum. We show that quantum gravitational effects through existence of the natural cutoffs result in more broadening of the wave packet profile during propagation relative to the ordinary quantum mechanics case.
Generalized Telebroadcasting of Entanglement Iulia Ghiu Romanian Journal of Physics 57,
1046-1052 (2012)
We present a generalization of the symmetric telebroadcasting of entanglement based on a non-maximally quantum channel shared between the senders and receivers. The entanglement of a bipartite two-level system is transmitted to two pairs of spatially separated observers.
Multicritical Behaviors of the Spin-3/2 Blume-Emery-Griffiths Model on a Cellular Automaton N. Seferoglu, G. Sezgin Romanian Journal of Physics 57,
1053-1064 (2012)
A computational study based on the cellular automaton has been done to investigate the phase transition of the spin-3/2 Blume-Emery-Griffiths (BEG) model. In the study, the ferromagnetic spin-3/2 BEG model with repulsive biquadratic coupling is simulated by using the cooling algorithm improved from the Creutz cellular automaton (CCA). The temperature dependence of the order parameters and associated fluctuations are calculated at various of the model parameters and the phase diagrams of the model are constructed in the ($D/J$, $kT/J$) and ($K/J$, $kT/J$)plane in the absence and presence of the external magnetic field. The phase diagrams of the model exhibit a rich variety of behaviors. It is shown that different kinds of phase transitions take place between the disordered, ferromagnetic, ferrimagnetic and antiquadrupolar phases for various of model parameters at a magnetic field value in the interval $-0.06 \le h/J \le 0$. In contrast, there is only a transition between disordered and ferrimagnetic phases in the interval $-0.2 \le h/J < -0.06$. Results are compared with other approximate methods.

Application of Multi-Step Differential Transform Method for the Analytical and Numerical Solutions of the Density Dependent Nagumo Telegraph Equation Vedat Suat Ertürk, Zaid M. Odibat, Shaher Momani Romanian Journal of Physics 57,
1065-1078 (2012)
The Differential Transform Method (DTM) is an analytical and numerical method for solving a wide variety of differential equations and usually gets the solution in a series form. The multi-step DTM is treated as an algorithm in a sequence of intervals for finding accurate approximate solutions. In this paper, this new algorithm is applied to a class of density dependent diffusion equations with memory-delay effect. The multistep differential transform solutions for various strengths of the density dependence along with bounds on the range of the convergence are obtained. The numerical solutions are obtained by the Runge-Kutta-Fehlberg 45 method. Then, a comparative study between the multi-step DTM and Runge-Kutta-Fehlberg 45 method is presented. The results demonstrate reliability and efficiency of the algorithm developed. Finally, the dependence of the traveling wave solutions on various parameters, particularly the memory-delay term, is discussed.
Elementary Particle Physics
Neutrino Energy Reconstruction in Neutrino-Nucleus Interactions D. Cheşneanu, A. Jipa Romanian Journal of Physics 57,
1079-1087 (2012)
In this paper, we present two methods to reconstruct the neutrino energy for neutrino interactions in the few-GeV energy range. We used GENIE - a new neutrino Monte Carlo generator - to generate events and compute the cross sections for neutrino-nucleus interactions. The present study is useful for improving underground detectors discovery potential for determining the neutrino properties.
Nuclear Physics
Compact Formulas for Rotational Bands Energies in Transuranic Region R. Budaca, A. A. Raduta Romanian Journal of Physics 57,
1088-1102 (2012)
Analytical formulas for the excitation energies as well as for the electric quadrupole reduced transition probabilities in the ground, beta and gamma bands provided by the asymptotic limit of coherent state model were applied for description of strongly deformed nuclei from the transuranic region. Numerical calculations were performed for 12 nuclei which share some common features. Comparison of the calculation results with the corresponding experimental data shows a very good agreement. The parameters involved in the proposed model satisfy evident regularities being interpolated by smooth curves. The formulas provided for $E2$ transition probabilities are very simple and reproduce quiet well the experimentally observed behavior of intraband and interband transitions in case of strongly deformed systems.
Can the Coherent State Model Describe the Triaxial Nuclei ? P. Buganu, A. A. Raduta Romanian Journal of Physics 57,
1103-1112 (2012)
The equations characterizing the Sextic and Mathieu Approach (SMA) are derived through a semi-classical treatment of the Coherent State Model (CSM) Hamiltonian. In this manner the potentials in $\beta$ and $\gamma$ variables respectively, show up in a quite natural way which contrasts their ad-hoc choice when SMA emerges from the Liquid Drop Model (LDM). The two formalisms, SMA and CSM, are applied for 180Hf.
AFM-Nanoindentation Study of an Irradiated Aluminum Alloy C. Ionescu, L. S. Craciun, E. S. Barna, P. M. Racolta, I. Burducea, M. Straticiuc, A. T. Serban Romanian Journal of Physics 57,
1113-1121 (2012)
In the present paper Atomic Force Microscopy (AFM) was used to capture the surface topography and then using a diamond tip mounted to a metal foil cantilever, to indent the surface and measure the material’s hardness. Six aluminum alloy samples were measured. Five of them are part of the control system diaphragm from the primary circuit of the VVR-S nuclear research reactor. They stayed in the active zone of the reactor for more than 40 years (neutron flux 5·102 neutrons/cm2 sec), while the other one is an unirradiated aluminum alloy from the same period of time. In this experiment the hardness was obtained from direct area measurement of the AFM impression. The hardness values are different for each indentation made and also for each sample analyzed. Regarding the unirradiated sample this is slightly higher than those reported in literature.
Condensed Matter
Effect of 1, 2- Hexadecadeniol and LiBEt3H Superhydride on the Size of FePt Nanoparticles M. Farahmandjou Romanian Journal of Physics 57,
1122-1127 (2012)
Monodisperse magnetic FePt nanoparticles have potential applications in high performance high-density magnetic storage media. In this paper, FePt nanoparticles were synthesized by reduction of FeCl2.4H2O and Pt(acac)2 at 250°C under N2 atmosphere. The effect of 1,2 Hexadecadeniol and LiBEt3H on the size and uniformity of FePt nanoparticles have been studied. TEM observations revealed that 1,2 Hexadecadeniol as reducing reagent, first create the 2 nm Pt core by releasing Pt atoms from Pt(acac)2 in nucleation stage at 190°C and then intense LiBEt3H superhydride increase the size of FePt nanoparticles to 5 nm by releasing the Fe atoms from FeCl2.4H2O in growth stage at 210°C, when added to the reaction solution. The mean diameter of FePt nanoparticles decrease to 4 nm by increasing reaction temperature to 250°C in reflux stage. XRD patterns showed that FePt nanocrystals form L10 superlattice structure after annealing at 700°C for 4 hours. The results of EDS analysis indicated that the composition of FePt nanoparticles in nucleation, growth and beginning of the reflux stage give Fe14Pt86, Fe63Pt37, and Fe58Pt42 stoichiometry, respectively.

FT-IR, FT-RAMAN Spectral Analysis and Density Functional Theory Calculations Studies of 3-Chloro-2-Nitrobenzyl Alcohol S. Ramachandran, G. Velraj Romanian Journal of Physics 57,
1128-1137 (2012)
The solid phase FT-IR and FT-Raman spectra of 3-Chloro-2-nitrobenzyl alcohol (CNBA) have been recorded in the regions 4000–400 cm−1 and 4000–100 cm−1, respectively. The spectra were interpreted with the aid of normal coordinate analysis following a full structure optimization and force field calculations based on the density functional theory (DFT) using the standard B3LYP/6-31+G(d,p) method and basis set combinations. The DFT force field transformed to natural internal coordinates was corrected by a well established set of scale factors that were found to be transferable to the title compound. The IR and Raman spectra were predicted theoretically and compared with the experimental spectra.
Lasers
Three Frequency Undulator Radiation in Presence of Betatron Oscillation Vikesh Gupta, Shailesh Gupta, Abhishek Verma Romanian Journal of Physics 57,
1138-1147 (2012)
In this paper we study the three frequency undulator radiation for higher harmonics with the inclusion of off axis contribution. When electron enters the field off axis it causes additional oscillations due to which intensity and gain reduction take place. To enhance the intensity and gain we introduce a new scheme i.e., the three frequency undulator scheme.
Optimization of Operation of Tera Hertz Nano-Laser at the Base of Three-Barrier Resonance Tunnel Structure with Shifted Bottoms of Potential Wells M. V. Tkach, Ju. O. Seti, V. O. Matijek Romanian Journal of Physics 57,
1148-1157 (2012)
The quantum mechanical theory of active conductivity is developed within the model of rectangular potentials and different effective masses of electron in the different elements of open plane three-barrier resonance tunnel structure. For the experimentally investigated resonance tunnel structure with In1-xGaxAs – wells and In1-xAlxAs – barriers the analysis of conductivity of monochrome electronic beam interacting with the electromagnetic field in approximation of weak signal is performed. It is shown that for the three-barrier resonance tunnel structure with guided shifts of inner potential wells bottoms there exists such position of inner potential barrier respectively the outer ones, at which the density of excited current is minimal and the density of output current from the system is maximal. Herein, the maximal negative conductivity proportional to the radiation intensity of quantum cascade laser active element is formed in the desired range of frequencies due to the quantum transitions between two lower electron quasi-stationary states.
Biophysics
Study of the Second Universality Class (U2) Processes from Physics and Biology Dan-Alexandru Iordache, Viorica Iordache Romanian Journal of Physics 57,
1158-1166 (2012)
The accomplished study pointed out that a huge number of accommodation – growth – dis-accommodation processes from completely different fields (compression – decompression of rocks, behavior of magnetic materials under photo-irradiation, growth processes of living beings, etc) obey to the same time evolution equation corresponding to the second (U2) Universality class. This equation represents both the solution of West’s equation: $\dot{y} = \gamma_1 \cdot y^{p_W} -\gamma_2 \cdot y$ and of Delsanto’s phenomenological universality equation: $\dot{p} = \beta \dot p + \gamma \cdot p^2$ , where: $p = \tfrac{1}{y}\cdot \tfrac{dy}{d\tau}$. The present work reports the obtained results concerning: a) the physical meaning of West ($\gamma_1$, $p_W$, $\gamma_2$) and Delsanto ($\beta$, $\gamma$, $p_o$) parameters of the different nature studied processes, b) the change of these parameters values which describe the complex processes with transition from the auto-catalytic stage to a relaxation one, c) the sudden and repeated changes of these parameters values, corresponding to some oscillations of certain U2 processes (e.g. of the living beings growth).

S. Aureus Response to Accelerated
electrons and Low Dose X-Rays R. Focea, A. Poiata, D. Creanga, T. Luchian Romanian Journal of Physics 57,
1167-1176 (2012)
The impact of low level irradiation on the cell density of S. aureus samples (ATCC 25923) was studied as well as the irradiated germ resistance to antibiotics. Both electron beam irradiation and X-ray exposure were performed with doses between 30 and 120 Gy The bacterial cell density exhibited a significant minimum in the case of the X-ray exposed samples, while for accelerated electrons a curve with a slight maximum was recorded. Certain tendency of increasing the resistance to antibiotics in the X-ray exposed samples was recorded but no detectable changes could be noticed for accelerated electrons.
Genotoxic Effects of Electromagnetic Exposure to ELF Fields Investigated at the Level of Meristematic Tissues C. Ionita-Mironescu, D. Vrincianu, I. Bara, D. Creanga, M. Racuciu Romanian Journal of Physics 57,
1177-1183 (2012)
Cytogenetic investigation was carried out focused on the response of wheat and barley seedlings to the exposures to 50 Hz/3.65 mT and respectively 50 Hz/7.0 mT magnetic fields. The presence of abnormal ana-telophases was noticed in all samples with significant increased incidence for the higher magnetic field. The differentiated behavior of wheat and barley was discussed both for mitotic index and chromosomal aberration percentage.
Environmental Physics
ICP-MS Determinations of Heavy Metals in Surface Waters from Transylvania C. Voica, M. H. Kovacs, A. Dehelean, D. Ristoiu, A. Iordache Romanian Journal of Physics 57,
1184-1193 (2012)
This study proposed to investigate the quality of surface waters used as raw water source by Water Treatment Plants which provide drinking water for a large number of inhabitants. Studied area includes two districts from Transylvania, namely Cluj and Salaj. A wide number of metals were identified in all water samples; usually in most water samples the amounts of such toxic metals were between the ranges of few µg/l. Inductively coupled plasma mass spectrometry (ICP-MS) is an analytical technique used for elemental determinations; the Perkin Elmer Elan DRC(e) ICP-MS instrument was used to perform water samples analysis.
Determination of Lead and Strontium Isotope Ratios in Wines by Inductively Coupled Plasma Mass Spectrometry A. Dehelean, C. Voica Romanian Journal of Physics 57,
1194-1203 (2012)
Thirteen wine assortments from Romania were investigated from the point of view of their metal content and isotopic ratios 206Pb/207Pb and 86Sr/87Sr. The determination was performed by ICP-QMS. The aim of this study was to detect and quantitatively determine the toxic metals in some white and red wine samples and to investigate them from the point of view of isotopic ratios 206Pb/207Pb and 87Sr/86Sr. Six metals with toxicology significant concentration were identified, from which nickel (16 µg l−1 to 94 µg l−1) are perhaps originating from the technological procedure of vinification (fermentation in stainless steel tanks). Traces of Pb (2 µg l−1 to 47 µg l−1), Hg (value reported in a sample of wine - 200 µg l−1), As (0.3 µg l−1 to 12 µg l−1), Cd (0.08 µg l−1 to 1.4 µg l−1), Cr (46 µg l−1 to 400 µg l−1) were also found. The 87Sr/86Sr ratio depends on the geographic location of the soil where the plants grew, so that it can be used as a tracer of wine origin. 206Pb/207Pb and 206Pb/208Pb ratios could be significantly influenced by anthropogenic factors. These ratios may be used to differentiate natural and anthropogenic Pb contamination. It seems that for the wines studied, the lead content comes from natural Pb.

Measurements of Radium Levels in Bottled Natural Spring Water of Marmara Region (Turkey) Urkiye Akar, Orhan Gurler, Aysegul Kahraman, Sezai Yalcin, Gokay Kaynak, Ozcan Gundogdu Romanian Journal of Physics 57,
1204-1210 (2012)
Drinking water may contain varying levels of radioactivity. It is therefore important to determine the radium levels in drinking waters for public health and radiation protection. This paper presents results of 226Ra concentrations in bottled spring waters. The concentration of radium has been assessed in the bottled natural spring water samples commercially available in Turkey. Measurements of 226Ra concentrations in bottled natural spring water samples were carried out by AlphaGUARD, measuring the radon in equilibrium with radium. The radium concentration in these samples is found to be between 0.03 and 0.43 Bq·L-1. These values were compared with the recommended safe limits for drinking water.
Astrophysics
Neutrino and Anti-Neutrino Energy Loss Rates Due to Iron Isotopes Suitable for Core-Collapse Simulations Jameel-Un Nabi Romanian Journal of Physics 57,
1211-1221 (2012)
Accurate estimate of neutrino energy loss rates are needed for the study of the late stages of the stellar evolution, in particular for cooling of neutron stars and white dwarfs. The energy spectra of neutrinos and antineutrinos arriving at the Earth can also provide useful information on the primary neutrino fluxes as well as neutrino mixing scenario (it is to be noted that these supernova neutrinos are emitted after the supernova explosion which is a much later stage of stellar evolution than that considered in this paper). Recently an improved microscopic calculation of weak-interaction mediated rates for iron isotopes was introduced using the proton-neutron quasiparticle random phase approximation (pn-QRPA) theory. Here I present for the first time the fine-grid calculation of the neutrino and anti-neutrino energy loss rates due to 54,55,56Fe in stellar matter. In the core of massive stars isotopes of iron, 54,55,56Fe, are considered to be key players in decreasing the electron-to-baryon ratio (Ye) mainly via electron capture on these nuclide. Core-collapse simulators may find this calculation suitable for interpolation purposes and for necessary incorporation in the stellar evolution codes. The calculated cooling rates are also compared with previous calculations.

Some Exact Bianchi Type-I Cosmological Models in Scalar-Tensor Theory of Gravitation with Time Dependent Deceleration Parameter Anirudh Pradhan, Anand Shankar Dubey, Rajeev Kumar Khare Romanian Journal of Physics 57,
1222-1235 (2012)
A new class of a spatially homogeneous and anisotropic Bianchi type-I cosmological models of the universe for perfect fluid distribution within the framework of scalar-tensor theory of gravitation proposed by Saez and Ballester (Phys. Lett. 113:467, 1986) is investigated by considering time dependent deceleration parameter. Two different physically viable models of the universe are obtained. The modified Einstein’s field equations are solved exactly and the models are in good agreement with recent observations. Some physical and geometric properties of the models are also discussed.
The Z=(t/z) Type Plane Gravitational Waves of Gauge Invariant Generalized Field Equations with Asymmetric Fundamental Tensor in Plane Symmetry S.R. Bhoyar, R. S. Rane, S. D. Katore, A.G. Deshmukh Romanian Journal of Physics 57,
1236-1251 (2012)
In a previous paper Bhoyar and Deshmukh [https://doi.org/10.1007/s10773-011-0853-4] have found the wave solutions of both the weak and strong, non-symmetric unified field equations of Einstein, Bonner and Schrodinger in a plane symmetric space-time for Z=(t/z)-type plane gravitational waves. In this paper, the solutions of plane gravitational waves in Buchdahl’s [Q.J.Math.8,89,(1957) and 9,257,(1958)] field theories have been investigated by authors in plane symmetry which was studied and defined by Taub [Annals of Math 53,472-490,(1951)]. It has been exhibited that under certain conditions solutions of gauge invariant generalized field equations exist in plane symmetry.
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