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2019

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Articles 12481 - 12510 of 13032

Full-Text Articles in Physical Sciences and Mathematics

Halogen Bonding Interactions For Aromatic And Non-Aromatic Explosive Detection, Arjun K. A. Jaini, Lillian B. Hughes, Michael K. Kitimet, Kevin John Ulep, Michael C. Leopold, Carol A. Parish Jan 2019

Halogen Bonding Interactions For Aromatic And Non-Aromatic Explosive Detection, Arjun K. A. Jaini, Lillian B. Hughes, Michael K. Kitimet, Kevin John Ulep, Michael C. Leopold, Carol A. Parish

Chemistry Faculty Publications

Improved sensing strategies are needed for facile, accurate and rapid detection of aromatic and nonaromatic explosives. Density functional theory was used to evaluate the relative binding interaction energies between halogen-containing sensor model molecules and nitro-containing explosives. Interaction energies ranged from –18 to –14 kJ/mol and highly directional halogen bonding interactions were observed with bond distances ranging between 3.0 and 3.4 Å. In all geometry optimized structures, the sigma-hole of electropositive potential on the halogen aligned with a lone pair of electrons on the nitro-moiety of the explosive. The computational results predict that the strongest interactions will occur with iodine-based sensors …

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One-Pot Enol Silane Formation-Mukaiyama Aldol Reactions: Crossed Aldehyde-Aldehyde Coupling, Thioester Substrates, And Reactions In Ester Solvents, C. Wade Downey, Grant J. Dixon, Jared A. Ingersoll, Claire A. Fuller, Kenneth W. Maccormac, Anna Takashima, Rohina Sediqui Jan 2019

One-Pot Enol Silane Formation-Mukaiyama Aldol Reactions: Crossed Aldehyde-Aldehyde Coupling, Thioester Substrates, And Reactions In Ester Solvents, C. Wade Downey, Grant J. Dixon, Jared A. Ingersoll, Claire A. Fuller, Kenneth W. Maccormac, Anna Takashima, Rohina Sediqui

Chemistry Faculty Publications

Trimethylsilyl trifluoromethanesulfonate (TMSOTf) and a trialkylamine base promote both in situ enol silane/silyl ketene acetal formation and Mukaiyama aldol addition reactions between a variety of reaction partners in a single reaction flask. Isolation of the required enol silane or silyl ketene acetal is not necessary. For example, crossed aldol reactions between α-disubstituted aldehydes and non-enolizable aldehydes yield b- hydroxy aldehydes in good yield. In a related reaction, the common laboratory solvent ethyl acetate functions as both an enolate precursor and a green reaction solvent. When thioesters are employed as enolate precursors, high yields for additions to non-enolizable aldehydes are routinely …

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First Photometric Investigation Of Some Asas Binary Systems, Burak Ulaş Jan 2019

First Photometric Investigation Of Some Asas Binary Systems, Burak Ulaş

Turkish Journal of Physics

We present the first light curve solutions of the four binary systems observed and catalogued by the All Sky Automated Survey (ASAS) program. The light curves are analyzed by using PHOEBE software, which is based on the Wilson?Devinney method. The light curve parameters are derived and the estimated physical parameters are calculated from the result of the analyses. We compare our targets to well-known binaries of similar type on the Hertzsprung-Russell diagram and mass-radius plane. The evolutionary states of the components are also discussed.

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Quality Control Of Silicon Pixel Wafers For The Cms Phase-1 Pixel Upgrade, Kamuran Di̇lsi̇z, Süleyman Durgut, Kai Yi, Leonard Spiegel Jan 2019

Quality Control Of Silicon Pixel Wafers For The Cms Phase-1 Pixel Upgrade, Kamuran Di̇lsi̇z, Süleyman Durgut, Kai Yi, Leonard Spiegel

Turkish Journal of Physics

The CMS detector at the CERN Large Hadron Collider features as its innermost component a silicon pixel detector. The original pixel detector was completely replaced during the 2016-2017 winter technical stop. One of the goals of this Phase-1 Upgrade of the pixel detector was to replace the sensors in the original CMS forward pixel detector with new, unirradiated sensors. The new CMS forward pixel detector must survive an integrated luminosity of 300 fb$^{-1}$ before being replaced again prior to the High-Luminosity LHC era. Just as in the original construction, the Phase-1 forward pixel sensors were made of n$^{+}$-in-n Diffusion Oxygenated …

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Electroweak Decays Of Unflavored Mesons In Poincaré Covariant Quark Model, Vadzim Haurysh, Viktor Andreev Jan 2019

Electroweak Decays Of Unflavored Mesons In Poincaré Covariant Quark Model, Vadzim Haurysh, Viktor Andreev

Turkish Journal of Physics

This work presents the procedure for obtaining integral representation of the radiative decay constant in the Poincaré-covariant quark model, based on Poincaré-invariant quantum mechanics. In the course of the work the authors give numerical estimates of magnetic moments of the light quarks ($u,d,s$) from the $V\rightarrow P\gamma$ decay, based on the calculation method of the observer that was previously developed. This technique is generalized in the case of the decay $P\rightarrow V\gamma$ with further numerical calculation of mixing angles $\eta-\eta^{\prime}$ of pseudoscalar mesons. Within the framework of the offered approach, we obtain a self-consistent model that describes radiative and leptonic …

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Second-Order Gauge-Invariant Perturbation Theory And Conserved Charges Incosmological Einstein Gravity, Emel Altaş Ki̇raci Jan 2019

Second-Order Gauge-Invariant Perturbation Theory And Conserved Charges Incosmological Einstein Gravity, Emel Altaş Ki̇raci

Turkish Journal of Physics

Recently a new approach in constructing the conserved charges in cosmological Einstein gravity was given. In this new formulation, instead of using the explicit form of the field equations, a covariantly conserved rank-four tensor was used. In the resulting charge expression, instead of the first derivative of the metric perturbation, the linearized Riemann tensor appears along with the derivative of the background Killing vector fields. Here we give a detailed analysis of the first-order and the second-order perturbation theory in a gauge-invariant form in cosmological Einstein gravity. The linearized Einstein tensor is gauge-invariant at the first order but it is …

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Privacy-Preserving Attribute-Based Keyword Search In Shared Multi-Owner Setting, Yibin Miao, Ximeng Liu, Robert H. Deng, Robert H. Deng, Jjguo Li, Hongwei Li, Jianfeng Ma Jan 2019

Privacy-Preserving Attribute-Based Keyword Search In Shared Multi-Owner Setting, Yibin Miao, Ximeng Liu, Robert H. Deng, Robert H. Deng, Jjguo Li, Hongwei Li, Jianfeng Ma

Research Collection Yong Pung How School Of Law

Ciphertext-Policy Attribute-Based Keyword Search (CP-ABKS) facilitates search queries and supports fine-grained access control over encrypted data in the cloud. However, prior CP-ABKS schemes were designed to support unshared multi-owner setting, and cannot be directly applied in the shared multi-owner setting (where each record is accredited by a fixed number of data owners), without incurring high computational and storage costs. In addition, due to privacy concerns on access policies, most existing schemes are vulnerable to off-line keyword-guessing attacks if the keyword space is of polynomial size. Furthermore, it is difficult to identify malicious users who leak the secret keys when more …

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Study Of A = 100-150 Superdeformed Mass Region By Using Two-Parameterformula, Vidya Devi, Jagjit Singh Matharu Jan 2019

Study Of A = 100-150 Superdeformed Mass Region By Using Two-Parameterformula, Vidya Devi, Jagjit Singh Matharu

Turkish Journal of Physics

Empirical formulae of rotational spectra consisting two parameters, such as single-term energy formula, E = aJb for spin J , and ab formula, were used to study the different features of superdeformed band in A = 100-150 mass region nuclei. The nuclear kinematic and dynamic moment of inertia for the ground-state rotational bands were calculated for this purpose and both showed gradual rise with rotational frequency. The study of ΔI = 2 staggering effects in the γ-ray energies, where the two sequences J = 4i; 4i + 1 and J = 4i + 2, (i = 0; 1; ...) are …

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Effects Of Cooling Rate On The Atomic Structure And Glass Formation Process Of Co90 Zr10 Metallic Glass Investigated By Molecular Dynamics Simulations, Murat Çeltek, Sedat Şengül Jan 2019

Effects Of Cooling Rate On The Atomic Structure And Glass Formation Process Of Co90 Zr10 Metallic Glass Investigated By Molecular Dynamics Simulations, Murat Çeltek, Sedat Şengül

Turkish Journal of Physics

In this study, the atomic structure and the glass formation process of Co90 Zr10 metallic glass alloy were studied by molecular dynamic simulation based on the embedded atom method using four different cooling rates. The average atomic volume and the potential energy of the system were observed to be strongly dependent on the cooling rate during rapid solidification, and the glass transition temperature decreased with decreasing cooling rate. The radial distribution functions and the structure factors derived from molecular dynamics simulations at 300 K agreed well with the experimental and other molecular dynamics results. The coordination numbers calculated at 300 …

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Effect Of Left-Handed Materials In Surface Plasmon Excitation And Propagationlength, Ari̇f Engi̇n Çeti̇n Jan 2019

Effect Of Left-Handed Materials In Surface Plasmon Excitation And Propagationlength, Ari̇f Engi̇n Çeti̇n

Turkish Journal of Physics

We investigated the dispersion relation of surface plasmons (SPs) excited in a medium comprised of a left-handed material (LHM) layer. We investigated different light polarizations in SP excitation along an LHM-metal interface. We studied SP excitation through a classical Kretschmann geometry, employing an LHM interlayer between a dielectric and a metal layer. Using this three-layer configuration, we investigated the effect of LHM medium on characterizing SP propagation length, which is directly related to the energy of the surface waves.

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Autonomous Piston Engine Guided By The Transduction Of Radiation Pressure Inoptomechanical Brownian Motors, Yusuf Gül Jan 2019

Autonomous Piston Engine Guided By The Transduction Of Radiation Pressure Inoptomechanical Brownian Motors, Yusuf Gül

Turkish Journal of Physics

We consider the autonomous piston engine in a coupled cavity scheme in an optomechanical setup. Treating the radiation field as working fluid, we investigate the transduction of virtual photons due to ground state excitations. Rabi-like energy splittings and Casimir effect are shown by avoided crossing in the eigenfunction spectrum. Second order coherence functions are employed to analyze the bunching of the cavity and mechanical mode in optomechanical implementation of Brownian motors. The imbalance in occupation numbers of the working modes is investigated for the power for work extraction. We explore the guidance of the radiation field in work extraction. We …

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Lorentz-Violating Effects In Single W Boson Production At The Lhc, Serdar Spor, İnanç Şahi̇n Jan 2019

Lorentz-Violating Effects In Single W Boson Production At The Lhc, Serdar Spor, İnanç Şahi̇n

Turkish Journal of Physics

We investigate the Lorentz-violating effects of Standard Model Extension (SME) in single W boson production process pp → pγp → p W- q' X at the Large Hadron Collider (LHC). We employ the Weizsacker-Williams approximation for photons emitted from one of the incoming proton beams and consider γq → W- q' as a subprocess in the proton-proton collision. The behavior of the differential cross-section for various orientations of the constant background fields is obtained by taking into account longitudinal and transverse polarization states of the final W bosons.

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Synthesis, Characterization, And Magnetic Properties Of Nanosizedzn0.5co0.5erxfe2-Xo4 Prepared By Coprecipitation Method, Zouheir Bitar, Doaa El-Said Bakeer, Ramadan Awad Jan 2019

Synthesis, Characterization, And Magnetic Properties Of Nanosizedzn0.5co0.5erxfe2-Xo4 Prepared By Coprecipitation Method, Zouheir Bitar, Doaa El-Said Bakeer, Ramadan Awad

Turkish Journal of Physics

In the present work, the effect of doping zinc cobalt ferrite by different concentrations of Er3+ on structural, optical, and magnetic properties was studied. Nanosized Zn0.5Co0.5ErxFe2-xO4 (0 ≤ x ≤ 0.2) was synthesized by the coprecipitation method. XRD analysis confirmed the formation of one phase face FCC spinel structure belonging to the Fd3m space group. TEM exhibited that the particle size decreased with the increase of Er3+ content, which is in agreement with XRD results. Two significant absorption bands from FTIR spectra were observed between 400 and 600 cm-1. The band gap energy value obtained from UV-Vis increased with the …

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First- And Second-Law Thermodynamic Analyses Of A Combined Natural Gas Cyclepower Plant: Sankey And Grossman Diagrams, Mehmet Onur Karaağaç, Ahmet Kabul, Hasan Oğul Jan 2019

First- And Second-Law Thermodynamic Analyses Of A Combined Natural Gas Cyclepower Plant: Sankey And Grossman Diagrams, Mehmet Onur Karaağaç, Ahmet Kabul, Hasan Oğul

Turkish Journal of Physics

The natural gas combined cycle power plant is one of the best options for generating electricity due to its use of low carbon fuels, high efficiency, and operational flexibility. These plants consist of a combination of Brayton and Rankine cycles, and investigation of these cycles is performed in this paper. Here the parameters of pressure and temperature used in the calculations are taken from a combined cycle power plant. The net power output of the system at 25 °C ambient temperature and 101.325 kPa pressure was calculated as 45 and 12 MW for Brayton and Rankine cycles, respectively. In addition, …

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Effect Of Al Doping On The Magnetic And Elastic Properties Of Fe65 Ni35 Invar Alloys, Asli Çakir Jan 2019

Effect Of Al Doping On The Magnetic And Elastic Properties Of Fe65 Ni35 Invar Alloys, Asli Çakir

Turkish Journal of Physics

Invar alloys have great importance due to their low thermal expansion coefficient. The effect of Al doping on Fe65 Ni35 Invar alloy was investigated by temperature-dependent magnetization and elastic modulus measurements. First, 0.44 at% and 2.24 at% of Al were substituted for Ni. Then X-ray diffraction measurements, Rietveld refinements, and scanning electron microscopy studies were performed to understand the effect of Al-doping on the face-centered cubic structure. The elastic modulus of Fe65 Ni35 and the Al-doped samples were measured in the temperature range 300 ≤ T ≤ 870 K using impulse excitation. The temperature dependence of magnetization and elastic modulus …

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Enhanced Efficiency Of Cds/P3ht Hybrid Solar Cells Via Interfacial Modification, Sali̇h Yilmaz, İsmai̇l Polat, Murat Tomaki̇n, Ahmet Ünverdi̇, Emi̇n Bacaksiz Jan 2019

Enhanced Efficiency Of Cds/P3ht Hybrid Solar Cells Via Interfacial Modification, Sali̇h Yilmaz, İsmai̇l Polat, Murat Tomaki̇n, Ahmet Ünverdi̇, Emi̇n Bacaksiz

Turkish Journal of Physics

The present paper examines the effects of surface modification of CdS with diverse dyes on fabricated CdSbased hybrid solar cells. The X-ray diffraction results showed that CdS thin films had a hexagonal phase with a preferred orientation along the (101) plane. Scanning electron microscopy indicated that the CdS specimen was composed of a granular structure while a P3HT layer was formed from tiny grains. Band gaps of the CdS thin films and the P3HT layer were 2.45 eV and 1.98 eV, respectively. The absorption spectra showed that different dye loading caused an increase in the absorbance of CdS thin films …

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On Memory Effect In Modified Gravity Theories, Ercan Kiliçarslan Jan 2019

On Memory Effect In Modified Gravity Theories, Ercan Kiliçarslan

Turkish Journal of Physics

In this work, we discuss the gravitational memory effect in higher derivative and infinite derivative gravity theories and give the detailed relevant calculations whose results were given in our recent works. We show that the memory effect in higher derivative gravity takes the same form as in pure GR at large distances, whereas at small distances, the results are different. We also demonstrate that, in infinite derivative gravity, the memory is reduced via error function as compared to Einstein's gravity. For the lower bound on the mass scale of nonlocality, the memory essentially reproduces the usual GR result at distances …

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Pressure-Induced Structural Phase Transition And Electronic Structure Of In$_{1-X}$Ga$_{X}$P Alloys: A Dft Study, Kabita Khoirom, Indrajit Sharma, Brojen Singh, Ramkumar Thapa Jan 2019

Pressure-Induced Structural Phase Transition And Electronic Structure Of In$_{1-X}$Ga$_{X}$P Alloys: A Dft Study, Kabita Khoirom, Indrajit Sharma, Brojen Singh, Ramkumar Thapa

Turkish Journal of Physics

We present the density functional calculation to study the pressure-induced structural phase transition and electronic structure of In$_{1-x}$Ga$_{x}$P ($x =$ 0.0, 0.25, 0.5, 0.75, 1) alloys. We report the optimized structural parameters such as lattice constant, bulk modulus, and derivative of the bulk modulus of the alloys. Our calculation confirms that the alloys in the zinc-blende structure are more stable than in the rock-salt structure. The phase transition study from zinc-blende to rock-salt under pressure shows that the transition pressure increases with an increase in doping concentration. The energy band diagram of the alloys in the zinc-blende phase reveals a …

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Determination Of Effective Resonance Energies For The $^{185}$Re(N,$\Gamma )^{186}$Re And $^{187}$Re(N,$\Gamma )^{188}$Re Reactions By Cadmium Ratio Method, Mustafa Güray Budak Jan 2019

Determination Of Effective Resonance Energies For The $^{185}$Re(N,$\Gamma )^{186}$Re And $^{187}$Re(N,$\Gamma )^{188}$Re Reactions By Cadmium Ratio Method, Mustafa Güray Budak

Turkish Journal of Physics

The effective resonance energy ($\bar{E}_{r})$ values for the $^{185}$Re(n,$\gamma )^{186}$Re and $^{187}$Re(n,$\gamma )^{188}$Re reactions were measured by using the cadmium ratio method. $^{197}$Au and $^{98}$Mo isotopes were selected as dual monitors to determine the epithermal neutron spectrum shape factor in the irradiation sites of a 37 GBq $^{241}$Am-Be neutron source. The analytical grade rhenium(VII) oxide samples were diluted with Al$_{2}$O$_{3}$ powder to reduce neutron self-shielding effects, and they were put into 1-mm thick small cylindrical polytetrafluoroethylene (PTFE) boxes. Samples were irradiated in a $^{241}$Am-Be neutron source. The activation produced in the irradiated samples was measured in close-counting geometry on the …

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Higher-Order Differential Cross Section Calculation For The Associated Production Ofa W Boson And Jets In The Electron Decay Channel At A Center-Of-Mass Energy Of 13tev In Proton-Proton Collisions, Kadi̇r Öcalan Jan 2019

Higher-Order Differential Cross Section Calculation For The Associated Production Ofa W Boson And Jets In The Electron Decay Channel At A Center-Of-Mass Energy Of 13tev In Proton-Proton Collisions, Kadi̇r Öcalan

Turkish Journal of Physics

Higher-order cross sections for the production of a W boson in association with jets in the electron decay channel are presented in this study. Cross sections were calculated in a fully differential way using a computational framework based on proton-proton collisions at a center-of-mass energy of 13 TeV. The differential cross section predictions in the fiducial phase-space were compared at next-to-leading order (NLO) and next-to-NLO (NNLO) in perturbative quantum chromodynamics (pQCD). The differential results are reported for the variables including the jet multiplicity, the invariant mass of the W boson, transverse momentum, the jet rapidity, and the electron pseudorapidity that …

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Effect Of Low-Temperature Oxidation On The Properties Of Tivn/Vn Multilayer Coatings, Merve Ertaş Uslu, Özge Doğan, Leyla Çolakerol Arslan Jan 2019

Effect Of Low-Temperature Oxidation On The Properties Of Tivn/Vn Multilayer Coatings, Merve Ertaş Uslu, Özge Doğan, Leyla Çolakerol Arslan

Turkish Journal of Physics

An extensive study of the surface oxidation process on the properties of TiVN/VN multilayer coatings deposited by RF magnetron sputtering on Mg alloys was performed. TiVN/VN multilayer coatings with a total thickness of 660 nm and different layer numbers of 5, 11, and 33 were oxidized by annealing at 450K under partial oxygen pressure. Electronic, mechanical, and tribological properties of these coatings were characterized by X-ray photoelectron spectroscopy (XPS), scanning electron microscope, nanoindentation measurements, and scratch tester. The experimental results showed that the oxidation of TiVN/VN multilayer coatings leads to better performance in terms of surface roughness, hardness, and wear. …

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The Influence Of Crosslinking Temperature On The Spectroscopic, Thermal, And Mechanical Properties Of Poly(Vinyl Alcohol)/Zeolite Composites, Cenk Denktaş Jan 2019

The Influence Of Crosslinking Temperature On The Spectroscopic, Thermal, And Mechanical Properties Of Poly(Vinyl Alcohol)/Zeolite Composites, Cenk Denktaş

Turkish Journal of Physics

The aim of this study was to understand the effect of crosslinking temperature on the spectroscopic, thermal, and mechanical properties of poly(vinyl alcohol) (PVA)/zeolite composites. The PVA nanocomposite films were prepared using the solvent casting method with tartaric acid as the crosslinker. The changes in the structures of pure PVA film and powder clinoptilolite (CL) and nanocomposite films were analyzed by means of ATR-FTIR spectroscopy. The effect of both crosslinking temperature and CL on the composite films prepared by the addition of constant CL to the polymer matrix at different crosslinking temperatures (series II) and pure PVA films prepared with …

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The Effect Of Phenylboronic Acid-Based Self-Assembled Monolayers On Theperformance Of Organic Field-Effect Transistors (Ofets), Tuğbahan Yilmaz Aliç Jan 2019

The Effect Of Phenylboronic Acid-Based Self-Assembled Monolayers On Theperformance Of Organic Field-Effect Transistors (Ofets), Tuğbahan Yilmaz Aliç

Turkish Journal of Physics

The dielectric/semiconductor interface is one of the most important components strongly affecting the performance of organic field-effect transistors (OFETs). To improve OFET parameters, we applied a series of phenylboronic acid derivatives as self-assembly molecules between dielectric and organic semiconductor layers. Device performance parameters, especially threshold voltage, current on/off ratio, and subthreshold slope, were improved. To elucidate the mechanism, dielectric/semiconductor interfaces were analyzed using atomic force microscope and contact angle techniques.

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Thin-Shell Wormholes From Kiselev Black Holes, Peter Kuhfittig Jan 2019

Thin-Shell Wormholes From Kiselev Black Holes, Peter Kuhfittig

Turkish Journal of Physics

This paper discusses the theoretical construction of thin-shell wormholes from Kiselev black holes. We assume a barotropic equation of state for the exotic matter on the shell. While most of these wormholes are unstable to linearized radial perturbations, a limit argument is used to show that under certain conditions, stable solutions can be found.

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Nonlinear Frequency Conversion Of Light Inside A Microcavity, Emre Yüce Jan 2019

Nonlinear Frequency Conversion Of Light Inside A Microcavity, Emre Yüce

Turkish Journal of Physics

Changing the color of light in a small mode volume is essential for applications that require on-chip operation. Microcavities are profound structures given their property to confine light in a small mode volume. Here, I numerically investigate the frequency conversion of light in a microcavity and show that the frequency converted light intensity is distinguished from an open medium such as an optical fiber or a nonlinear crystal. I observe that the frequency converted light intensity increases with increased rate of change of the refractive index of the microcavity. Notably, this study shows that the intensity of the frequency converted …

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Method For Determination Of Water Hammer Conditions And Consequences Inpressurizers Of Nuclear Reactors, Vladimir Skalozubov, Oleg Chulkin, Denis Pirkovskiy, Igor Kozlov, Yuriy Komarov Jan 2019

Method For Determination Of Water Hammer Conditions And Consequences Inpressurizers Of Nuclear Reactors, Vladimir Skalozubov, Oleg Chulkin, Denis Pirkovskiy, Igor Kozlov, Yuriy Komarov

Turkish Journal of Physics

Results of known experimental and computed studies of conditions for water hammers (WHs) in reactor pressurizers are analyzed. It is found that when emergency opening of pilot-operated safety valves of the pressurizers of nuclear reactors happens, WHs can be generated on pressurizer elements, and amplitudes of hydrodynamic load pulses significantly override the limiting values. An original method for determination of the WH conditions and consequences in the case of emergency filling of the pressurizers of nuclear reactors is proposed. Unlike the traditional Joukowski formula, the presented method considers the key features and effects of the WH conditions and consequences in …

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Application Of The Fractional Oscillator Model To Describe Damped Vibrations, Sergo Rekhviashvili, Arsen Pskhu, Praveen Agarwal, Shilpi Jain Jan 2019

Application Of The Fractional Oscillator Model To Describe Damped Vibrations, Sergo Rekhviashvili, Arsen Pskhu, Praveen Agarwal, Shilpi Jain

Turkish Journal of Physics

We consider a model of damped vibrations based on fractional differentiation. The model given is completely consistent with the classical model of vibration with viscous damping. We find the relation between the order of fractional differentiation in the equation of motion and Q-factor of an oscillator. The proposed approach seems more appropriate for the physical nature of the described system. The experiment with a vibrating piezoelectric plate, performed as part of the study, showed good agreement with the model and confirmed that the fractional oscillator model can be used to describe strongly damped vibrations.

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Comparison Of Geometric And Drive-Induced Nonlinearities In Doubly Clamped,Thermoelastic Nanoelectromechanical Systems, Mehmet Seli̇m Hanay Jan 2019

Comparison Of Geometric And Drive-Induced Nonlinearities In Doubly Clamped,Thermoelastic Nanoelectromechanical Systems, Mehmet Seli̇m Hanay

Turkish Journal of Physics

The performance of resonant sensors based on nanoelectromechanical systems depends critically on the maximum amplitude of oscillation reached in the linear regime. The maximum linear amplitude is determined by nonlinear mechanisms that can originate from the material, geometric and transduction mechanism related factors. Here we compare the two competing effects, the geometric and drive-induced nonlinearities, for a commonly used device family, the thermoelastically driven, doubly clamped beams. We find that the geometric nonlinearity dominates for most of the device designs used in the literature, however the drive-induced nonlinearity becomes the determining factor for thicker beams with small electrode lengths.

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Determination Of Fluence Rate Distribution In A Multilayered Skin Tissue Model Byusing Monte Carlo Simulations, Hali̇l Arslan, Bahar Pehli̇vanöz Jan 2019

Determination Of Fluence Rate Distribution In A Multilayered Skin Tissue Model Byusing Monte Carlo Simulations, Hali̇l Arslan, Bahar Pehli̇vanöz

Turkish Journal of Physics

Information on light-tissue interaction is important for clinical applications of lasers. The Monte Carlo technique is one of the commonly used methods to simulate photon propagation and to describe energy absorption in biological tissues. In this study, fluence rate distributions of 633 nm and 830 nm light inside a multilayered skin tissue model have been investigated by using two different simulation software programs: GAMOS tissue optics plug-in and MCML. Results of the plug-in for the fluence rate distributions are in very good agreement with the ones from MCML for both of the wavelengths. This shows that GAMOS tissue optics plug-in …

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The Hirota-Satsuma Coupled Kdv Hierarchy On Noncommutative Phase-Space, Abdelali Saidi, Moulay Brahim Sedra Jan 2019

The Hirota-Satsuma Coupled Kdv Hierarchy On Noncommutative Phase-Space, Abdelali Saidi, Moulay Brahim Sedra

Turkish Journal of Physics

In the present contribution, the Hirota-Satsuma coupled KdV hierarchy on noncommutative phase-space is investigated using the noncommutative extension of Lax pair generating technique. In particular, the explicit representation of its associated Lax pair operators is constructed. It is shown that the obtained results for phase-space noncommutativity case reduce back to the standard commutative case when θ goes to ½.

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