Volume 61, Number 56, 2016
Theoretical and Mathematical Physics
Anisotropic Universe SpaceTime NonCommutativity and Scalar Particle Creation in the Presence of a Constant Electric Field Slimane Zaim Romanian Journal of Physics 61,
743754 (2016)
We study the effect of the noncommutativity on the creation of scalar particles from vacuum in the anisotropic universe spacetime. We derive the deformed KleinGordon equation up to second order in the noncommutativity parameter using the general modified field equation. Then the canonical method based on Bogoliubov transformation is applied to calculate the probability of particle creation in vacuum and the corresponding number density in the $k$ mode. We deduce that the noncommutative spacetime introduces a new source of particle creation.
A Nonperturbative Method for QCD Renata Jora Romanian Journal of Physics 61,
755767 (2016)
Based on specific properties of the partition function and of the quantum correlators we derive the exact form of the beta function in the background gauge field method for QCD with an arbitrary number of flavors. The all order beta function we obtain through this method has only the first two orders coefficients different than zero and thus is equivalent to the ’t Hooft scheme.
The analytical expression of the Chernoff polarization of the Werner state Iulia Ghiu, Aurelian Isar Romanian Journal of Physics 61,
768773 (2016)
We review the quantum Chernoff bound and the quantum degree of polarization based on this bound. Then we find the analytical expression of the quantum degree of polarization based on the quantum Chernoff bound for the Werner state, as a function of the parameter that defines this state.
The Successive Differentiation Method for Solving Bratu Equation and BratuType Equations AbdulMajid Wazwaz Romanian Journal of Physics 61,
774783 (2016)
In this work, we apply the successive differentiation method for solving the nonlinear Bratu problem and a variety of Bratutype equations. We use the successive differentiation of any linear or nonlinear ordinary differential equation to determine the values of the function’s derivatives at $x = 0$. The Taylor series of the solution can be established by using the derived coefficients. The algorithm handles the problem in a direct manner without any need to restrictive assumptions. We emphasize the power of the method by applying it to Bratu equation and a variety of Bratutype equations.
New Results for Multidimensional Diffusion Equations in Fractal Dimensional Space Min Ma, Dumitru Baleanu, Yusif S. Gasimov, XiaoJun Yang Romanian Journal of Physics 61,
784794 (2016)
The multidimensional diffusion equations in fractal dimensional space started to play an important role in physics. In this paper we present the analytical solutions of the multidimensional diffusion equations in fractal dimensional spaces by using the method of separation of variables. The graphs of the exact solutions are presented and the accuracy and efficiency of the approach are revealed for a class of local fractional partial differential equations.
Spectral Solutions for Fractional Differential Equations via a Novel Lucas Operational Matrix of Fractional Derivatives W.M. AbdElhameed, Y.H. Youssri Romanian Journal of Physics 61,
795813 (2016)
In this research article, a novel operational matrix of fractionalorder differentiation of Lucas polynomials in the Caputo sense is established. Based on this matrix along with the application of tau and collocation spectral methods, two efficient numerical algorithms for solving multiterm fractional differential equations are proposed and analyzed. Some new formulae for Lucas polynomials are stated and proved for investigating the new algorithms. The convergence and error analysis of the suggested Lucas expansion are investigated carefully. Some new inequalities including the modified Bessel function of the first kind and the wellknown golden ratio are stated and proved. Some numerical tests are carried out for some specific and important types of problems including the BagleyTorvik, Ricatti, LaneEmden and oscillator equations. The results obtained are compared with some existing ones in open literature and it is noticed that the two proposed algorithms are robust, accurate and easy to apply.
Classification of Families of Exact Localized Solutions of PotentialFree Schrödinger Equation in Spherical Coordinates Zhengping Yang, WeiPing Zhong, Dumitru Mihalache Romanian Journal of Physics 61,
814826 (2016)
The families of exact localized solutions of threedimensional (3D) potentialfree Schrödinger equation in spherical coordinates are classified by setting the values of four parameters: the modulation depth and three integer “quantum” numbers, namely the radial, the colatitudinal, and the azimuthal numbers. The generic isointensity shapes of these 3D localized linear wavepackets are divided into two main classes: (i) combined diskshaped and ringshaped patterns and (ii) necklaceringshaped patterns.
Localized Nonlinear Matter Waves in OneDimensional BoseEinstein Condensates with Spatiotemporally Modulated Two and ThreeBody Interactions DengShan Wang, Yushan Xue, Zhifei Zhang Romanian Journal of Physics 61,
827841 (2016)
In this paper, we study the localized nonlinear matter waves in onedimensional BoseEinstein condensates with spatiotemporally modulated two and threebody interactions and timedependent external potentials. By means of similarity transformation, two exact solutions of the onedimensional cubicquintic GrossPitaevskii equation are obtained explicitly. It is demonstrated that both attractive two and threebody interactions and attractive twobody plus repulsive threebody interactions support localized nonlinear matter waves in BoseEinstein condensates trapped in timedependent external potentials. The dynamics of the localized nonlinear matter wave is analyzed and some breathing and quasibreathing solutions are found.
Nuclear Physics
ProtonNeutron Normal Fluid Mixtures Şerban Mişicu Romanian Journal of Physics 61,
842856 (2016)
Baryonic mixtures composed of protons and neutrons are investigated within the nuclearfluid dynamics. The present approach extends the traditional NFD approach with elements borrowed from the continuum mechanics of fluid mixtures as outlined and masterfully expounded by Truesdell in his monography on classical field theories more than half a century ago. From the mass and momentum balance equations of fluid mixtures I derive some qualitative aspects regarding the role of the diffusion force and its dependence on the employed effective N − N interactions. The wave propagation is considered for infinite isotropic spinsaturated $p  n$ mixtures and the dependence of the frequencies on the protontoneutron density ratio is discussed.
Heavy Ion Orbiting and Regge Poles (ii) F. Carstoiu, M. Lassaut, L. Trache, V. Balanica Romanian Journal of Physics 61,
857874 (2016)
We discuss two specific examples of heavy ion orbiting. A first example, $\alpha+^{16}$O at 54.1 MeV reaction dominated by strong optical potentials shows all characteristics of a strongly refractive scattering: Fraunhofer cross over at very forward angles, deep Airy oscillation, rainbow bump, significant increase of the cross section at large angles. We demonstrate semiclassically that this in fact is a typical orbiting reaction. In a second example, $\alpha+^{28}$Si at 18.0 MeV, we describe a special kind of heavy ion orbitingbutterfly scattering, with diffractive oscillations in the entire physical angular range, determined by Regge pole dominance.
Semiclassical Approaches to the Coupling between Nuclear Dipole Modes and Surface Vibrations Virgil Baran, DorinGheorghe David, Dragos Iustin Palade Romanian Journal of Physics 61,
875884 (2016)
Within a microscopic transport model based on Vlasov equation we investigate the macroscopic structure of pygmy dipole resonance in terms of the coupled motions of neutrons in excess, protons of the core and neutrons of the core respectively. The resulting picture is consistent with the predictions based on schematic models with generalized separable interactions which extend the Brink model for Giant Dipole Resonance and are able to predict the pygmy dipole modes. Then we explore how the surface vibrations affect the dipole dynamics as a consequence of the coupling between these collective modes.
Effect of the Heavy Ions to the Silicon Detectors Adnan Kilic Romanian Journal of Physics 61,
885891 (2016)
Silicon particle detectors are used in several applications such as accelerators in high energy physics, space, nuclear physics experiments and medicine. Thereby, it is crucially important to understand the effects of various particles with different energies on performance of silicon detectors. In this study, it has been focused on recoil heavy ions ($Z \ge 3$) produced by 50 to 500 MeV protons in silicon. In order to investigate the effects of the recoil heavy ions on silicon, it has been simulated some physical quantities such as variety, ranges, linear energy transfers (LET) and nonionizing energy loss (NIEL) of the recoil heavy ions through GEANT4 (Geometry And Tracking) [1], FLUKA (FLUktuierende KAskade) [2] and SRIM [3] Monte Carlo tools.
Study of the Optical Materials Degradation Caused by Gamma Radiation and the Recovery Process by Controlled Heat Treatment M.R. Ioan Romanian Journal of Physics 61,
892902 (2016)
In this paper we tested two optical materials available in the commercial area – TEMPAX and BK7 glasses. Their outstanding optical properties in the 532 nm and 633 nm wavelengths make them appropriate to be used as parts of optical systems which operate in hostile radiation environments. In this direction, we exposed different samples of these types of optical glass to a 1.25 MeV energy gamma flow. The power and polarization measurements have revealed the effect of gamma irradiation as the degree of change in optical transmission, in the visible region of the electromagnetic spectrum, for 633 nm and 532 nm. Postirradiation measurements have revealed a reduction in the optical transmission. Since the proportions of those color signals builds the entire color range of the resulted images, damaging any one of them in the irradiation process will lead to overall deterioration of the image. Besides that, it was studied the variation of the absorption at 297.15K and 441.73K temperatures. By fitting, using the relation (2) which took into account the variation of the absorption as a function of dose and wavelength, there were obtained fitting parameters A_{1}, A_{2} and K. Further, we presented the relative variation as a function of temperature for the most important of them (A_{1}, K). Their relative variations as a function of dose, temperature and glass type are: for BK7 (HeNe)  A_{1} = 26.41 %, K = 11.49 %; for TEMPAX (HeNe)  A_{1} = 23.11 %, K = 31.82 %; for BK7 (Nd:YAG)  A_{1} = 2.7 %, K = 13.46 %; for TEMPAX (Nd:YAG)  A_{1} = 26.84 %, K = 47.02 %.
Condensed Matter
Materials Microstructure Characterization Using High Resolution TimeofFlight Neutron Diffraction G.D. Bokuchava Romanian Journal of Physics 61,
903925 (2016)
The neutron diffraction has a great potential for microstructure characterization of various constructional materials due to high penetration power of neutrons and nondestructive character of the method. Using timeofflight (TOF) technique at pulsed neutron sources allows to record complete diffraction patterns in wide range of interplanar spacing at fixed scattering angles and to analyze polycrystalline materials with complex structures. In current paper a brief overview of some typical examples of materials microstructure investigations by means of TOF neutron diffraction is given. The experiments were performed on the Fourier diffractometers FSD and HRFD at the IBR2 fast pulsed reactor in FLNP JINR (Dubna, Russia).
Microparticles and Electroconductive Magnetorheological Suspensions I. Bica, M. Balasoiu, M. Bunoiu, L. Iordaconiu Romanian Journal of Physics 61,
926945 (2016)
Magnetorheological and electroconductive magnetorheological suspensions are of great interest for both: scientific and applicative research. In the present paper, the production methods of microparticles and electroconductive magnetorheological suspensions, together with the involved electroconductive mechanisms are reviewed.
Hydrophilic versus Hydrophobic Oleate Coated Magnetic Particles E. Puscasu, L. Sacarescu, A. Domocos, C. Leostean, R. Turcu, D. Creanga, M. Balasoiu Romanian Journal of Physics 61,
946956 (2016)
Oleic acid was used to develop hydrophobic coating shell for magnetic nanoparticles (MNPs) stabilization in hydrophobic medium; sodium oleate was used to yield hydrophilic coating of MNPs in colloidal aqueous suspension. Microstructural and magnetic properties were investigated by standard methods. The interpretation of the observed microstructural and magnetic features was based on the differences in coating shell arrangement, i.e. single oleate layer in hydrophobic colloidal MNPs compared to double oleate layer in hydrophilic MNP sample. In this latter case coated particle interaction seems to be favored resulting in some clusters with character of mass fractals (2.4 fractal dimension) as shown from SAXS data analysis.
Filtration of Flue Gas in Microfluidic Devices Using Dielectrophoresis Adrian Neculae, Madalin Bunoiu, Antoanetta Lungu, Mihai Lungu Romanian Journal of Physics 61,
957969 (2016)
The paper investigates the possibility to improve the filtering process of flue gas by controlling entrapment of suspended nanoparticle using dielectrophoresis (DEP). A realistic description of the manipulation process requires an accurate description of microchannel geometry and a precise evaluation of the DEP forces spatial distribution. The work presents the results of a numeric study which aims to characterize the functionality of a 3D DEPbased microsystem for the selective manipulation of nanometric particles. The analysis focuses on the nanoparticles having radii ranging from 50 to 150 nm, particles that cannot be filtrated by classical techniques but have a harmful effect for environment and human health. The solutions of the DEP force and particle concentration distribution for a typical separation device with interdigitated electrodes array are calculated using the COMSOL Multiphysics finite element solver. The performances of the device are analyzed in terms of a specific quantity related to the separation process, called Filtration efficiency. The simulations provide the optimal set of values for the control parameters of the separation process, and represent a useful tool in designing of microfluidic devices for separating nanoparticles from flue gas.
Research on the Method for Measurement of Graphene's Carrier Density Z.K. Liu, Y.N. Xie, L. Geng, D.K. Pan, P. Song Romanian Journal of Physics 61,
970979 (2016)
For large areas, fast and simple method for measurement of graphene’s carrier density is critical to the application of graphene. The paper presents a method for measurement of graphene’s carrier density using infrared phase contrast microscopy. The method is based on the fact that, in far infrared and some middle infrared band, the phase change is more sensitive than the intensity change in graphene when the light passes through it, and the ratio of phase and intensity becomes bigger with the increase of carrier density. The method can be twodimensional, fast and convenient to detect graphene carrier density. The method will contribute to future research and application of graphene.
The Effect of Optical Phonons on the Electronic States in TwoWell Resonant Tunneling Structure Driven by Electric Field at Finite Temperature Ju. Seti, M. Tkach, M. Pan'kiv, O. Voitsekhivska Romanian Journal of Physics 61,
980991 (2016)
The electronphonon interaction in twowell resonant tunneling nanostructure driven by constant electric field at finite temperature is studied within the effective mass approximation for the electron and dielectric continuum model for the confined optical and interface phonons using the approach of temperature Green’s functions. The effect of electronphonon interaction on electronic states and radiation band of twowell cascade of injectorless quantum cascade laser is observed. It is established that the frequency of laser generation weakly depends on the temperature while the width of radiation band increases.
Electronic Energy Dispersion and Structural Properties on Graphene and Carbon Nanotubes D. Racolta, C. Andronache, D. Todoran, R. Todoran Romanian Journal of Physics 61,
992998 (2016)
In the present paper we discuss the energy band structure and structural properties of graphene and carbon nanotubes used on determination of its electronic, optical and optoelectronic properties. We calculated the onedimensional E–k relation of carbon nanotube, started from quantification the twodimensional E–k of the graphene sheet along the circumferential direction of the nanotube, used a tight binding model based on the nearest neighbor interaction which includes one pz orbital per carbon atom. The electronic structure of nanotube can be defined by its diameter and chirality (m, n). For the zigzag nanotube, if (m–n) is a multiple of 3, is not gap in the energy spectrum, showing metallic character, if (m–n) is not a multiple of 3, the gap is nonzero, the character is semiconducting. For the armchair nanotube (m–n = 0), the character is always metallic. The size of the energy gap of nanotubes is inversely proportional to the diameter. This opens the way to controllable manipulations of phasecoherent mesoscopic phenomena.
Plasma Physics
Characterization of a Dielectric Barrier Discharge Generated in Open Space with Flowing Working Gas S.D. Anghel, I.E. Vlad Romanian Journal of Physics 61,
9991008 (2016)
The work presents a new possibility to generate a cold dielectric barrier discharge in open space in helium, argon or a mixture of the two gases. The plasma is characterized by electrical and optical methods. It was proven that the discharge is thermally nonaggressive and that its emission can be controlled by adjusting the gas composition.
Optics
Digital OffAxis Holographic Microscopy: from Cells Visualization, to Phase Shift Values, Ending with Physiological Parameters Evolution Mona Mihailescu, Irina A. Paun, Eugenia Vasile, Roxana C. Popescu, Alexandra V. Baluta, Diana G. Rotaru Romanian Journal of Physics 61,
10091027 (2016)
Digital offaxis holographic microscopy (DoHM) is a modern technique, which provides quantitative information about the samples in three dimensions. DoHM allows the analysis of living cells in their growth medium, without any kind of additional markers, leading to the values of many physiological parameters after processing the reconstructed images. This paper is a review about the research and development applications implying DoHM for the analysis of different biological samples: blood cells, yeast cells, neurons, cancer cells, and osteoblasts cells. The focus is on the values of the final physiological parameters, which can be determined with high accuracy in markerfree conditions, at the level of the single cell, such as refractive indices, hemoglobin content, dry mass, amplitude of the membrane fluctuations, cells elasticity, cells dimensions, rate of sedimentation, and transmembranar fluxes. Few aspects about the decoupling and focusing procedures are also summarized. This review addresses to students and researchers interested in realtime analysis of living cells in their natural environment.
Asymmetric Solitons in ParityTimeSymmetric DoubleHump ScarffII Potentials Pfengfei Li, Dumitru Mihalache, Lu Li Romanian Journal of Physics 61,
10281039 (2016)
Symmetric and asymmetric solitons that form in selffocusing optical waveguides with paritytime ($\cal PT$)symmetric doublehump ScarffII potentials are investigated. It is shown that the branch corresponding to asymmetric solitons bifurcates out from the base branch of $\mathcal{PT}$symmetric solitons with the increasing of the input power. The stability of symmetric and asymmetric stationary solitons is investigated by employing both linear stability analysis and direct numerical simulations. The effects of the soliton power, the separation between the two humps of the potential, the width and the modulation strength of the potential, on the structure of the linear stability eigenvalue spectrum is also studied. The different instability scenarios of $\cal{PT}$symmetric solitons have also been revealed by using direct numerical simulations.
Environmental and Earth Physics
Use of Cr39 Solid State Nuclear Track Detectors in Assessment of the Radon Exposure in Two Limestone Caves in Romania N. BicanBrişan, C. Cosma, A. Cucoş, D. Burghele, B. Papp, S. Constantin, M. Moldovan, S. Gîfu Romanian Journal of Physics 61,
10401050 (2016)
Radon concentration measurements were carried out using solidstate nuclear tracketch detectors (RSKS) type CR39 in Polovragi and Muierilor limestone caves from Easthern Carphatian (Romania). Two campaigns for measurements were performed in each cave (winter and spring seasons). The timeperiods for which measurements were performed provide reliable data for estimating the dose exposure to the radon for tourist guides. Higher radon levels were measured in Polovragi cave in the spring season, 3331 Bq$\cdot$m$^{3}$ being the highest value. In this cave the gradual accumulation of radon further and deeper into the cave in the absence of air movement inside the cave was demonstrated. Muierilor cave is characterized by slightly variation of radon concentration through the caves caused probably by the high air movement inside the cave. Some anomalies were recorded in several measurement points probably due to the local conditions.
Radiochemical Investigations on Natural Mineral Waters from Bucovina Region, Romania Marian Romeo Calin, Ileana Radulescu, Alina Catrinel Ion, Florinela Sirbu Romanian Journal of Physics 61,
10511066 (2016)
The access to a safe drinking water is essential to human health. In this respect, the major ion composition, electrical conductivity and pH of nine natural mineral drinking waters were studied. The waters originate from a volcanic aquifer containing carbonate rocks, situated in northern part of Romania. It was found that the low permeability of the aquifer allows a reduced infiltration of the rain water, seasonal influence showing good chemical stability, oscillating around less than 10%. Correlations were found between Ca$^{2+}$, Mg$^{2+}$ and HCO$_{3}^{}$ for both carbonated and noncarbonated natural mineral water sources. In addition, an assessment of dose and risk resulting from consuming these waters has been also performed. Gross alpha, gross beta and radionuclides of natural decay chains $^{238}$U, $^{232}$Th, $^{226}$Ra and $^{40}$K activity concentrations were measured, and the associate effective doses for these radionuclides were determined. The results for the effective doses calculated for an adult member of the public in Romania derived from the intake of naturally occurring radionuclides in these waters vary between: 0.32–1.87 (μSv/yr) for $^{40}$K; 0.82–1.56 for $^{238}$U; 1.10–12.25 (μSv/yr) for $^{232}$Th and 4.49–32.70 (μSv/yr) for $^{226}$Ra. Based on this, these waters can be recommended for regular consumption by infants and children, too. This assessment on natural mineral water springs from the Bucovina region updates data on the activity concentrations and effective doses due to intake of natural radionuclides from drinking water in Romania.
Prediction Method Applied for the Evaluation of the Tropospheric Ozone Concentrations in Bucharest C. Gavrila, A. Coman, I. Gruia, F. Ardelean, A. Vartires Romanian Journal of Physics 61,
10671078 (2016)
In this paper, we describe a prediction method applied for the evaluation of the troposphere ozone concentrations in the Romanian city of Bucharest; in this area, the pollution level is very high principally due to the traffic and multiple local sources. Using only meteorological data and some precursors of the ozone we estimate the ozone concentrations for a horizon of 24 hours. The minimization algorithm used here is the LevenbergMarquardt algorithm in the framework of the Scilab program. Sensitivity tests performed show the robustness of the results and a good applicability of this model for a shortterm prediction of the ozone.
Radioactivity Levels in Water and Paraffin Samples from the Decommissioned VVRS Nuclear Reactor by GammaRay Spectrometry I. Iorga, A. Scarlat, A. Pantelică, M. Drăguşin Romanian Journal of Physics 61,
10791086 (2016)
In view of radiological characterization of water from the reactor ponds and paraffin from the biological shield of the 2 MW VVRS nuclear research reactor undergoing decommissioning in IFINHH, activity concentrations of ^{60}Co, ^{134}Cs, ^{137}Cs, ^{152}Eu, and ^{241}Am artificial radionuclides, ^{234}Th ( ^{238}U decay), ^{214}Pb and ^{214}Bi (^{238}U  ^{226}Ra series), as well as ^{228}Ac, ^{212}Pb, and ^{208}Tl (^{232}Th series), and ^{40}K natural radionuclides have been determined by gammaray spectrometry. Their values were found to be lower than the clearance levels given by the radiological safety norms, except for ^{137}Cs in a water sample of about four times higher radioactivity.
Determination of Several Elements in Edible Mushrooms Using ICPMS Andreea Antonia Georgescu, Andrei Florin Danet, Cristiana Radulescu, Claudia Stihi, Ioana Daniela Dulama, Daniela Elena Chelarescu Romanian Journal of Physics 61,
10871097 (2016)
The determination of elements content in the fruiting bodies of mushrooms is essential in dietary intake studies, because this aliment is used in the diet of many countries. In this study the contents of several elements, including Mn, Fe, Cu, and Zn, in cap and stipe of ten edible mushroom species, were determinate by using ICPMS technique. These edible mushrooms species were collected from four sites of Dambovita County, Romania. After this study it was observed that mushrooms accumulate elements in different levels, in caps and stipes, depending on its species. It is well known that some elements cause a metal stress in the cells, resulting in the formation of ROS, survival of the microorganism in this stress is attributed to the induced biosynthesis of enzymes responsible for antioxidant defense.
The North Temperate Climate on LongTerm Timescales. Connection to Solar Variability Razvan Pirloaga, Venera Dobrica Romanian Journal of Physics 61,
10981107 (2016)
The Earth’s climate is influenced by solar variability in multiple ways: the wellknown effect of changes in the solar irradiance and also via the interaction of the solar wind with Earth’s magnetosphere resulting in the socalled geomagnetic activity. In this study we analyze the possible longterm effects of the solar variability as external natural forcing over the North temperate climate (35–65° N band) using near surface air temperature data from NCEP/NCAR Reanalysis database. The database has a global coverage by 2.5° latitude × 2.5° longitude and a temporal one from 1948 to present. The reanalyzed time series have been compared to the observed surface air temperature for several locations over the Northern Hemisphere, and the differences between them are discussed. In order to obtain the interdecadal and centennial trends in data, time series have been treated by means of successive 11 and 22 year running averages. The solar signals at time scales of Schwabe (11 year) and Hale (22 year) solar cycles have been computed as differences between the initial data and the interdecadal trend, and between the interdecadal and the centennial trends, respectively. The corresponding trends and the 11 and the 22 year signals in SAT are discussed.
Satellite Monitoring for a Safer Construction Environment S.F. Balan, V. Poncos, D. Teleaga, R. Nicolae, B.F. Apostol Romanian Journal of Physics 61,
11081119 (2016)
The results of Permanent Scaterrers Interferometry (PSI) technique is employed herein in order to identify some seismic risk features in certain zones of interest, such as Bucharest city area, capital of Romania, and the Nuclear Power Plant in Cernavoda. A comparison is also made between insitu and satellite monitoring. A dense sampling of the structures in terms of temporal deformation profiles is provided and further used to assess the stability and resilience of buildings. All these information are corroborated with seismic hazard maps in terms of peak ground accelerations (Bucharest case), highlighting areas with highrisk probability. Advanced satellite interferometric techniques help locate certain regional or local anomalies exemplified by ground uplifting or subsidence. These movements can be general when large areas are involved, (Bucharest city case), or they may occur on small areas, (Cernavoda city buildings) or those related to the zone of lake “Lacul Morii”, consisting of artificial filling areas.
Macroseismic Intensity Distribution of Some Recent Romanian Earthquakes A.P. Constantin, R. Partheniu, I.A. Moldovan Romanian Journal of Physics 61,
11201132 (2016)
Between years 2001 and 2004 a number of earthquakes with magnitudes which ranged from 3.9 to 5.0 occurred in the most seismically active areas of the Romanian territory. A macroseismic analysis of the effects produced on the Romanian territory has been conducted for these earthquakes, by using macroseismic questionnaires. Some of the observed intensities were significantly higher than those we could have expected after the earthquakes with such magnitudes. Effects have been evaluated from macroseismic observations giving maximum intensities estimated as VI–VII and VII in the MSK scale, respectively. Given the small to moderate size of earthquakes, many of the observed damages to buildings are due to their bad state, age, and poorly built without antiseismic protection, and hence particularly vulnerable.
