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Improvement of signal significance of Ds± meson's signalvia using artificial neural network
The aim of the analysis is to improve the significance of the Ds ± meson signal in ALEPH data which is recorded at LEP in the Ds± → π± + φ where φ mesons are reconstructed from φ →K+ K- decay channel. The analysis covers two phases. In first phase, reconstruction of particles in the decay channel is performed and input variables are stored to be used in classification. This phase is the machine learning part of the analysis. The second phase is the selection of an optimum algorithm for classification of signal and background. Improvement of significance of Ds meson's signal is performed after selection of the optimum algorithm and the evaluation of coefficients for relevant input variables which are stored in first phase. Classification is performed with the Toolkit for Multivariate Analysis (TMVA) which operates under the ROOT data analysis framework. TMVA includes many classification algorithms; the Boosted Decision Tree method is chosen as the optimum classification method.
Reflector savings in calculation of the critical mass
The critical mass which is known as the smallest amount of fissile material required in any system of geometry for a sustainable fission chain reaction can be approximately calculated by using the steady-state one-group neutron diffusion equation. In the solution of the diffusion equation, it is important if the core is just bare or surrounded by a reflector material. In such analytical calculations, it is seen that the mass and size of the bare system decreases dramatically if there is reflector material. This thesis considers the application of Monte Carlo Method to hypothetical bare and reflected systems in spherical, cylindrical and rectangular coordinates, and compares its results with those of analytical solutions of neutron diffusion equation for bare and reflected systems in three basic geometries, respectively. We show that our numerical calculations for the size of the systems in these geometries by Monte Carlo Method are in very good agreement with those of the analytical solutions. Our method is very simple, understandable and applicable in any computer program language, and the results are in consistent with those of analytical ones.
Investigation of structural, optical and electrical properties of undoped and boron doped indium oxide films growth by spray prolysis technique
Indium oxide films with undoped and boron doped were produced by spray pyrolysis method at a substrate temperature of 380 °C on the glass substrate using boric acid (H3BO3) as the dopant source. The effects of doping concentration on the features of undoped and boron doped In2O3 films have been investigated. The XRD analyses indicate that all films are polycrystalline with cubic structure, which is the dominant peaks of the (222), (400), (440) and (622) reflection planes with lattice parameter, approximately 9-10 Å. When the structure doped with boron, a decrease in band gap energy occurs. This decrease continues up to 0.03 M of boron additives and tends to increase again above this value. As the boron concentration increases up to 0.03 M, the resistivity value decreases whereas the carrier concentration and Hall mobility values increase, which caused by the scattering of carriers that are severely weakened due to increased crystal quality.
A study on the dosimetric properties of polycarboxylate cement used in dental treatments
Zinc Polycarboxylate cement is one of the few dental materials that demonstrate true adhesion to tooth structure. The powder is primarily zinc oxide, and the liquid is polyacrylic acid or a copolymer of that acid. In this study, the dosimetry properties of Zinc Polycarboxylate cement using thermoluminescence (TL) were investigated and determined the effectiveness of its use as a good dosimeter. As a result, the sample shows a good TL properties with three main peaks found around 140 ℃, 220 ℃ and 330 ℃. It has a wide linear dose response between 144 𝐺𝑦 and 2.3 𝐾𝐺𝑦 and good reusability with eight cycles of measurement. Keywords: Thermoluminescence, Dosimetry Properties, Zinc Polycarboxylate
The growth and characterization of Sn doped Al/ZnS/p-Si structures
In this study, undoped and Sn (tin) doped ZnS (zinc sulfide) solutions were coated on glass and p-type Si (silicon) crystal using the sol-gel method. The Sn contribution amount changed between 0%-10%. The films are coated 15 layers on glass and 6 layers on crystal. Optical parameters such as thickness d, forbidden band gap Eg and refractive index n of the materials were investigated by using UV-vis-NIR measurements of thin films coated on glass. The crystal structure of the materials was determined with help of XRD spectrum. According to the results obtained, it was observed that the films grown on both glass and crystal crystallize as a cubic structure. Current-voltage I-V measurements of doped and undoped ZnS/p-Si structures were taken at room temperature in the dark, and diode properties of the samples were investigated with the help of these measurements. Diode parameters such as ideality factor n, barrier height ϕb and series resistance Rs were calculated using Thermionic emission (TE), Norde, Lien and Cheung-Cheung methods. In addition, capacitance-voltage C-V measurements of doped and undoped ZnS/p-Si in the frequency range of 10kHz-1.5MHz were taken and diode parameters were determined in detail by using these measurements. In addition, illuminated I-V measurements of doped and undoped ZnS/p-Si structures were determined under 100mW/cm2 illumination power in order to investigate photodiode characteristics of the samples.
Fabrication and characterization of composite electrodes for the hybrid / electric vehicles applications
In recent years, significant research effort has been made in the automobile industry to reduce gas emissions. In this respect, developing energy storage materials for electrical vehicles, such as fuel cells, lithium-ion batteries and supercapacitors received great attention. In this thesis, various electrodes, electrolytes and current collectors were produced to investigate their usability and performance in supercapacitor applications. Electrodeposition and thermal oxidation methods were used to coat metallic surfaces and obtain Ni, Sn and Cu-based modified electrodes. To test their performance, modified electrodes were cycled in non-aqueous (ionic liquid) and aqueous (neutral, alkaline and acidic) electrolytes. Metal oxide-based electrodes were grown via cathodic coating from an ionic liquid on a steel current collector. The chemical properties and morphology of the films were examined with respect to changes in the applied voltage. Asymmetric flexible supercapacitors were fabricated using the modified electrodes and nonwoven graphite (textile) electrodes. The corrosion/deterioration behavior of the stainless-steel current collector was studied by comparing the performance of annealed and untreated steel mesh electrodes after polarization in different electrolytes. These studies indicated that electrodes produced by inexpensive methods show remarkable potential for use in automobile applications
Examination of the performance of anechoic chambers and reverberation rooms at low frequencies
Determination of sound power level of the noise source is based on sound pressure and sound intensity measurements. ISO 3740 series standards are used in that purpose. Measurements are performed in anechoic chamber or hemi-anechoic chamber satisfying the free field condition and reverberation room obeying the free diffusivity condition. The lower frequency (cut-off frequency) for the measurement is directly related to the physical structure of the rooms. The inverse square law is examined in determining the cut-off frequency for anechoic and hemi-anechoic chambers. For reverberation rooms, on the other hand, diffusivity control that is the adjacent band value difference, standard deviation and reverberation time measurements are performed. Sound pressure level measurements of a sound source can be performed in a verified anechoic, hemi-anechoic and a reverberation rooms. In addition, absorption coefficient measurements can also be performed in the reverberation rooms. The aim of this thesis is to examine the performances of TUBITAK UME anechoic chamber built according to ISO 3745 standard and TUB¨ ˙ITAK UME reverberation room built according to ISO 3741 standard below their cut-off frequencies. Concurrently, the other aim of thesis is to compare the measurement surfaces describes in ISO 3744 and ISO 3746 standards for the anechoic chamber based on the sound power level, the level of uncertainty contribution due to the measurement surface, the level of uncertainty contribution due to the number of microphones and directivity indices.
CERN-ATLAS deneyinde S= 13 TeV kütle merkezi enerjisi verisiyle B+ mezon üretim tesir kesitinin ölçülmesi
The differential cross section of B+ meson is presented as a function of transverse momentum and pseudorapidity. It is determined from the channel B+ ->J/psi K+ and reconstructed with using ATLAS pp collision dataset, Run2 2015 data with integrated luminosity of 3.2 fb-1. Measurement is done for 8 intervals of transverse momentum pT and 4 intervals of rapidity |y| covering the range 9 GeV < pT< 120 GeV and |y|< 2.25. B+ / B- ratio is consistent with MC and 13 TeV / 7 TeV cross-section ratio is consistent with the theoretical expectations.
A study on the mass attenuation coefficients of different tissues for human body using finite element method
The values and so the estimation of the total mass attenuation coefficient is an important parameter for the interaction of radiation with tissue and in dosimetry for the medical applications in radiology and in oncology. The full mass attenuation coefficient is identified by both photon energy in addition to constituent elements of the materials. Presently, the human phantoms and computer simulation is the main preferred methods to achieve this task. In this study a novel model design by Finite Element Method (FEM) interactive environment in order to simulate and calculate the mass attenuation coefficients of gamma ray for several human organs. These organs include tissue, adipose tissue, blood, brain, bone, muscle, lung, skin and eye lens. Commonly used Gamma ray with several energies has been tested and these energy ranges are;60KeV, 80KeV, 150KeV, 400KeV, 500KeV, 600KeV, 1000KeV, 1250KeV, 1500KeV, and 2000KeV. The results have been compared with theoretical methods XCOM program and simulation program-based Monte Carlo model which are GEANT4 and FLUKA program as well as NIST. The proposed model results are very close to XCOM results and are very close to NIST values. These results are more accurate than FLUKA and GEANT4 simulation packages. Therefore, this method can be considered as a new method with high accuracy in the calculation of the mass attenuation coefficients of human tissues that can be relied upon with reliability.
Analysis of the microstructure and corrosion behaviour of electrodeposited Fe and Fe alloys
Corrosion is material deterioration owing to materials' interaction with their surroundings. When the surface of metals/alloys is converted to a stable form having its oxide, hydroxide or sulphide state, corrosion progression (the deterioration of the material) could be ceased. This process is called passivation which is the main point of this thesis. This thesis aimed to obtain an iron-based alloy coating that can be passive. As Zn is a passivable element, it was used with Fe for alloy coating in this research. Fe and Fe alloys (Fe-Zn, Fe-Mn, Fe-Mn-Zn) have been electrodeposited potentiostatically on AISI 4140 steel in aqueous and ionic liquid media for corrosion resistivity. Ionic liquids containing solely anions and cations (without solvent) have been employed as metals and alloys electrodeposition baths. The corrosion behavior of resulting films obtained in ionic liquid media was compared with that of the films electrodeposited from aqueous solutions. A scanning electron microscope, an energy dispersive spectrometer, X-Ray Diffraction and a Fourier Transform Infrared Spectrometer were used to characterize the surface morphologies, compositions, and structures of the synthesized coatings. The corrosion behavior of the alloy coatings was determined in NaCl solution by linear sweep voltammetry. Bulk steel material itself is oxidized at the potential window in which metals/alloys fabricated in this work oxidize in NaCl solution. Therefore, inert substrate (graphite and platinum) was coated by the metals/alloys and analyzed in terms of corrosion behavior. It was found that growth conditions have a considerable effect on the corrosion properties of coatings. Fe, Mn and Fe-Mn obtained from ionic liquid deposition bath could have pitting-like corrosion. Zn based coatings (pure Zn, Zn-Fe, Zn-Mn or Zn-Fe-Mn) electrodeposited from ionic liquid could have passivation behavior. Fe-Zn modified electrode obtained from aqueous solution has passivation. However, ternary Zn-Fe-Mn alloy electrodeposited from an aqueous solution cannot show passivation behavior.
Acoustical analysis and evaluation of some culture and art centers in Gaziantep
In recent years, room acoustics, one of the subcomponents of acoustics, has received great attention among researchers for its ability to specify good hearing conditions for each audience and to ensure high speech intelligibility and clear perception of music and its components in cultural or art centers and auditoriums. Therefore, acoustical conditions should be taken into account to prevent corresponding acoustical defects. The main objective of this thesis is to perform a general evaluation of the acoustical performance of some selected major culture and art centers in Gaziantep using objective parameters such as RT, EDT, BR, TR, Ts, C80, D50, STI, and Background Noise values. The selected centers are the Şehitkamil Culture Center, Şehitkamil Art Center, and Şehitkamil Wedding Hall. The objective acoustical performance of the audience area in culture and art centers depends on the measured parameter obtained by sound level meter or computer programs. The selected culture and art centers will be simulated and analyzed using the ODEON room acoustics software.
Acoustic properties of pistachio shell additive polyester resin
The discovery and production of numerous new environmentally friendly materials have been made possible by the technology's quickening pace of development. This prompts research into the use of polymer composites in the sector, which stands out for its benefits and keeps growing daily. When it comes to environmental protection, polymers made from recycled PET are a key component of these composites.In this context, the polymer composition enriched with pistachio shells will hold a significant place in the area. The mechanical and acoustical properties of polymers obtained by adding pistachio shell powder in specific ratios were examined. Sound absorbing, Tensile, bending and Izod-Charpy Impact strength tests were conducted sequentially on moulded composite specimens. Additional to the mechanical and acoustical test, SEM analyses were conducted to produce complex, high- magnification images of the surface topography of all samples prepared. The outcomes demonstrated that the prepared composite offered effective mid-frequency sound absorption, which can be used as membrane absorbers. Additionally, the mechanical properties of the pistachio shell filling are improved, lengthening the lifespan of the composite panel.
Heavy-ion fusion reactions at extreme sub-barrier energies
Recent years have witnessed an increase in interest in the study of fusion reactions at extreme sub-barrier energies, despite the fact that it is challenging to measure them due to their extremely small cross sections. Such reactions are essential to understand the creation of heavy elements in varied settings. In the present thesis work, the status of the field is reviewed involving all the related theoretical and experimental works carried out so far. The unexpected behavior seen in the steep falloff of measured cross-sections at low incident energies is explained in detail using new physics concepts related to the fusion process of atomic nuclei. Besides that, the framework of the sudden and adiabatic approaches using different potential structures especially shallow and deep potentials is discussed through the supersymmetric phase equivalent potential concept in quantum theory.
An invariant mass method for the energy calibration ofneutral pions
Data collected in the 1990's from the ALEPH experiment at the LEP collider still has potential to provide new or improved precision measurements in particle physics. In the ALEPH data neutral pions suffer from poor calibration. In this study, an energy calibration based on a global mass constraint is applied to neutral pions in order to further improve the quality of ALEPH data. The calibration is obtained by modifying photon energies with a scale such that the mean reconstructed mass is equal to the nominal pion mass. Since the reconstructed mass of neutral pions is observed to run with energy, individual scales are determined for 50 energy intervals independently for both simulated and real data. The calibration is also performed independently for four π 0 topologies. We show that this procedure improves pion energy resolution and the agreement between simulated and real data. This calibration is expected to lead to improved statistical significance in measurements of particle production and help to reduce systematic errors in those analyses.
Evaluation of outfield radiation dose in the treatment of breastcancer with hypo-fractionated radiation therapy usingthermoluminescence dosimetry
The aim of the study was to evaluate the outfield radiation dose in the treatment of breast cancer using hypofractionated radiation therapy with thermoluminescence dosimetry, specifically TLD-100 (LiF: Mg, Ti). To assess the variability in TLD responses, we employed the element correction factor (ECF) generation method. For measuring point doses in organs outside the treatment fields, we placed sixteen TLD- 100 chips in nine specific locations within the Rando phantom used for breast cancer radiation treatment (260 cGy x 16 = 41.6 Gy in 16 fractions). The TLDs were read using a Harshaw QS 3500 manual type reader connected to a PC, where we studied and analyzed the thermoluminescence signals. The results indicated that the highest received dose values were observed in the esophagus (≈3960 cGy) and trachea (≈3464 cGy). Furthermore, our findings demonstrate that TLD-100 chips are suitable for measuring point doses in hypofractionated radiotherapy for breast cancer.
Variation of multiplication factor with enrichment for an enriched-uranium reactor
The criticality of a nuclear power reactor is one of the most important factors to be considered in any nuclear world. Multiplication factor, k, sometimes called as survival factor f, is the crucial parameter for achieving the criticality. There are many factors affecting the criticality and in the calculation of k: The thermal fission factor (η), the resonance escape probability (p), and the thermal utilization factor (ƒ) are some of them. Implicitly, the Moderator (graphite) to Fuel ratio (NMF) and the uranium-235 enrichment percent are what all these factors depend on. In order to determine the effects of these various parameters and to illustrate the relationship between these implicit factors and their impact on nuclear reactor criticality a computational method is applied, and the uranium-235 enrichment from 0.7 percent (uranium percent in nature) to 5.0 percent by weight (the maximum allowable in LEU) are examined to calculate the multiplication factor with the corresponding size and volume of the system under investigation. The minimum enrichment for a range of NMF as well as the minimum NMF ratio for a range of enrichment has been considered for the criticality as an optimization problem. Results are presented in Tables and Graphs, and the optimum conditions for the criticality have been discussed. Key
Investigation of first-stage sintering kinetics of UO2, ThO2 and (Th,U)O2 pellets manufactured by internal gelation technique of sol-gel process
The sol-gel process which is among the methods used for the production of UO2, ThO2 and ThO2-UO2 mixed oxide fuel pellets allows a high degree of micro-homogeneity of uranium and thorium in the solution stage. The first aim of this study was to develop an alternative method to produce uranium, thorium and mixed thorium-uranium dioxide fuel pellets by using internal gelation technique of sol–gel process. The second aim was to investigate shrinkage behavior and first-stage sintering kinetics of pellets compacted in the Ar-%5 H2 atmosphere using dilatometer. Shrinkage curves of the UO2, ThO2, ThO2-10%UO2 and ThO2-5%UO2 pellets obtained from the dilatometer were used to determine the sintering mechanism, the diffusion coefficients and the activation energy.
Synthesis and investigation of thermoluminescence properties of rare earth (Dy) doped CaAL4O7
In this study the thermoluminescence (TL) properties of calcium aluminate (CaAl4O7) doped with rare earth ion, Dysprosium (Dy), have been investigated in detail. CaAl4O7:Dy phosphors were synthesized by using the sol-gel method. The glow curves of the samples were evaluated by using 90Sr-90Y (≈ 0.04 Gy/s) beta source for different dose levels between 0.2 Gy and 864 Gy and the kinetic parameters such as activation energy (Ea), and order of kinetics (b) were calculated by using peak shape method, heating rate method, and computer glow curve deconvolution method. The results of the experiments have shown that the sample has two general order glow peaks; P1 at 125oC and P2 at 160 oC. The peak at 125oC has a kinetic order of b=1.5 and activation energy Ea= 0.5 eV. The fading characteristics of the sample were also studied over a period time. The samples were irradiated and stored in a darkroom at room temperature. The results have shown that, the intensity of the main glow peak (P1) of CaAl4O7: Dy at the end of the planned storage times reduced typically 51 % of its original value.
Solution of Klein-Gordon equation in D-dimension and its application in physical systems
The analytic and approximate solution of KG-equation in arbitrary dimension D are calculated by using Asymptotic Iteration Method. The system of some important type of potentials like harmonic oscillator potential, the Go'ldman-Krivchenkov potential and some exponential-type potentials such as Morse and Woods-Saxon potentials have been studied in the D-dimension. The corresponding eigenvalues are obtained. In addition, the total normalized eigenvectors are obtained after calculating normalization constant for each type of potentials. Furthermore, it is shown that application of Asymptotic Iteration Method in KG-equation gives the eigenvector solution in terms of the Gauss hypergeometric or its special cases using the wavefunction generator.
Computational modelling of highly mis-matched alloys of GaNAsP and GaNAsBi as a laser gain material
The aim of this thesis work is to model and investigate the electronic band structure and current density of highly mismatched alloys of GaNAsP and GaNAsBi. To reveal the importance of these highly mismatched alloys we provide a comparison of GaNAsP and GaNAsBi with their nitrogen free N-counterpart. The GaP-based dilute nitride direct bandgap material Ga(NAsP) is gaining importance for the monolithic integration of laser diodes on Si microprocessors. The major advantage of this newly proposed novel laser material system is the small lattice mismatch between GaP and Si. However, from first gain measurements it is found that Ga(NAsP)/GaP material system has high threshold current at room temperature. Therefore, we present a comprehensive theoretical analysis of band alignment and threshold current in dilute nitride direct bandgap Ga(NAsP)/GaP/AlGaP QWs on silicon substrates using model calculations. The comparison of our calculated results with that of the experimental data indicates that the Auger effect involving CHCC process can be considered as the dominant non-radiative loss mechanism at 300K. It has just recently reported that highly mismatched semiconductor alloys of GaAs(1-x)Bi(x) has also several novel electronic properties, including a rapid reduction in energy gap with increasing x and also a strong increase in spin-orbit-splitting energy with increasing Bi composition. We, therefore to understand the origins of the rapid reduction in energy gap and its consequences, study and compare band gap and critical thickness of GaNAsBi. The results indicate that GaNAsBi material can be used in optoelectronic applications in the long wavelength region.
Gaziantep şehrinin Şahinbey, Nurdağı ve İslahiye ilçelerinin topraklarında doğal radyoaktif seviyelerinin belirlenmesi
The aim of this thesis is determine of the level of natural radioactivity in 61 soil samples taken from different regions of Islahiye, Nurdagı and Sahinbey districts of Gaziantep city. 238U, 232Th and 40K radioactivity concentrations of radionuclides in soil samples taken from these district were measured by using a well type NaI(TI) detectors connected to multichannel analyzer (MCA). The results of the natural radioactivity of the region that have been evaluated according to specific criteria. Average specific activities of 238U, 232Th and 40K in soil samples taken from İslahiye, Nurdağı and Şahinbey districts in Gaziantep city were found to be 39.18 ± 21.52 Bq/kg, 44.30±20.81 Bq/kg and 325.54±42.13 Bq/kg, respectively. The average 40K activity values were found to be slightly lower than international average effective value given by UNESCEAR 2000 report. Key words: İslahiye, Nurdağı, Şahinbey, Gamma Spectroscopy, NaI(TI) detector.
A novel approach for heavy quarkonium spectra
In this work, we attempt to investigate heavy quark systems ( and ) in the non-relativistic framework using phenomenological inter-quark potentials. For this reason, we have developed a powerful and flexible theoretical formalism, within the frame of the Schrödinger equation, to use for the analysis of heavy quarkonium systems involving exactly solvable energy-dependent potentials, together with quasi-/conditionally-solvable and non-solvable interaction potentials. Our first application to exactly solvable systems has clarified that energy dependent term in the potential leads to saturation of the spectra and degree of saturation is governed by the magnitude of perturbation. Second application to quasi-exactly solvable potentials, which is the Coulomb plus linear potential with a quadratic term, has justified the success of the present formalism due to its wide range of applicability, considering the comparison of the findings obtained by the present approach with those of experimental results and the other theoretical predictions in the related literature. Finally, the application of this new technique to also non-solvable systems involving Cornell potential has shed some light on the questions concerning with the limitations of the traditional perturbation techniques.
Liquid drop model and alpha decay in nuclear structure study
Six different liquid drop model (LDM) formulas (LDM1, LDM2, LDM3, LDM4, LDM5 and LDM6) were analyzed to describe nuclear binding energy for 3252 nuclei which were classified into four groups; deformation group which contain six sets, decay mode group which contain two sets, spin group which contain six sets and final group which contain all nuclei. LDM6 was firstly formed and used in this study to represent nuclear binding energy. We determined the coefficients of all LDM formulas by using nonlinear regression method. Moreover we calculated root mean square (RMS) for all nuclei groups by using all LDM formulas. Comparison of experimental data of binding energy with calculations was also studied for all LDM formulas. It is shown in this study that by adding shell correction and shell effect terms to all LDM formulas RMS is being smaller. A systematic study on alpha decay half-lives using five different semi-empirical formulas for even-even, even-odd, odd-even and odd-odd nuclei was also done in this thesis. Calculated half-lives were carefully compared with measured ones for 459 different isotopes. Key words: Liquid drop model, binding energy, shell correction, shell effect, alpha decay, half-life, nonlinear regression.
The investigation of variation of TL dose response curve of natural calcite after annealing at different temperatures
The thermoluminescence (TL) studies of calcite mineral have resulted in the development of a wider range of applications in ceramic industry field. The TL glow curve shapes of minerals changes as a result of crystal purity, radiation dose, and thermal history previous the irradiation. In this study, the TL dose response of natural calcite samples of unannealed and annealed at different temperatures has been studied. The calcite samples that were collected from Elazığ-Ağın city in Turkey exhibit two main TL peaks following β-irradiation. The samples were annealed at 600, 700, 800, 900, 1000 oC from 15 minutes to 240 minutes and then they were irradiated at room temperature with a point beta source for different time durations to study TL dose response curve. It was observed that the annealings at 900 and 1000oC have high prononuced effects on the dose response curve of natural calcite.
Development of new thermoluminescent dosimeters for neutron measurements
The main purpose of the proposed study is the investigation of the possibility to be used as neutron dosimeters with the analysis of the dependence on thermoluminescent radiation dose by synthesizing the borates which is doped metal ions and were development of materials until obtaining the best thermoluminescent neutron dosimeters. Borate anion group-containing materials such as LiB3O5, Li2B4O7, BaB4O7, CaB4O7 and MgB4O7 were produced for to be used as neutron dosimeters by solid-state synthesis method and after the synthesizing process compounds which include borate anion group were be doped with metal ions by high temperature solid state method. Afterwards, for thermoluminescence measurement of doped materials with the aim of the characterization of dosimetric materials X-ray powder diffraction (XRD), Thermal (DTA, TGA), Scanning Electron Microscope (SEM) and Fourier Transform Infrared Spectroscopy (FTIR) analyses are done. As a result of this analyses, the thermoluminescence measurements of materials are taken. XRD patterns of the synthesized compounds have demonstrated compliance with borate peak in JCPDS card. FT-IR spectra results did not yield different band structure in compounds. Thermoluminescent measurement results show that neutron radiation-sensitive borate compound are produced. Thermal analysis of the neutron-sensitive compounds were performed. According to the results of this analysis borate compounds are thermally stable. In all borate compunds, 0.5Dy% doped CaB4O7 yielded highest thermoluminescence response. Doping with Dy, MgB4O7 compounds shows increased thermoluminescence response for neutron radiation. Using different concentrations of Dy, Ag, Cu, Eu, Mg and Gd dopants into Li2B4O7 gave good results of neutron-radiation sensitivity. In this study, borate compounds that result after neutron irradiation were compared with TLD-600/TLD-700 neutron dosimeters. Accordingly, the compounds exhibit an ideal fit for all conditions required for a neutron dosimeter. The work carried out under this thesis has reached the objectives.
A study on corrosion characteristics of AA2024 under different conditions
In this work the corrosion characteristics of bare aluminum based alloy (AA2024) and zinc coated AA2024 are studied in the aqueous solution having three different pH (2, 7 and 12). Apart from the traditional methods of aluminum coating (chromate conversion coating and zincating), this thesis suggests an alternative way to coat aluminum with a metal. A novel ionic liquid consisting of only cations and anions electrolyte is used for this purpose. AA2024 alloy in a deep eutectic solvent (DES) having zinc ions cannot be coated by zinc by applying anodic potential directly due to the typical characteristic of aluminium alloy which has Al2O3 thin layer occurring naturally on the aluminium surface. To electrodeposit zinc on aluminium alloy, an extreme anodic voltage (+1.65) is firstly applied for removing Al2O3 layer in Ethaline and then the cathodic potential (-1.5 V) is immediately applied in order to deposit zinc in-situ on newly prepared aluminium alloy surface which does not have Al2O3 anymore. Galvanised AA2024 displays the characteristic of an amorphous structure observed by SEM and XRD. Bare AA2024 has pitting corrosion at high potential in three aqueous medium use in this work (10 mM HCl, 0.5 M NaCl, 10 mM KOH). Zinc coated AA2024 has passivation behaviour in alkaline and acidic media. Corrosion resistance of zinc coated AA2024 alloy is almost as high as that of bare AA2024 in three different media. The work reported in this thesis presents that zinc coated AA2024 has more than six times higher corrosion resistance than bare Al2024 in alkaline medium (pH = 12).
Synthesis and thermoluminescence characteristics of rare earth doped nanophosphors
In this study we have investigated the thermoluminescence (TL) properties of Sr-doped magnesium tetraborate (MBO) and KCl doped zinc borate (ZnB2O4) nano phosphors, which were synthesized by using the high temperature solid-state and solution combustion method. The glow curves of the samples were evaluated by using 90Sr-90Y (≈ 0.04 Gy/s) beta source for different dose levels between 0.2 Gy and 288 Gy and the kinetic parameters such as activation energy (Ea), and order of kinetics (b) were calculated by using different methods. The experimental results for Sr-doped MBO nano phosphor indicated that it has main glow peak with highest intensity at approximately 200 °C with good linearity of the dose–response up to 570 Gy. On the other hand the experimental results for KCl doped ZnB2O4 nano phosphor has shown that it has a broad glow curve structure, which consists of nine glow peaks. The fading characteristics of the samples were also studied over a period time. The samples were irradiated and stored in a darkroom at room temperature. At the end of the planned storage times the normalized TL area, of Sr-doped MBO reduced typically 50% and KCl doped ZnB2O4 reduced 70% of its original value. Keywords: Thermoluminescence, dosimeter, kinetic parameter, MgB4O7:Sr, ZnB2O4:KCl, solid-state reaction method, solution combustion method, nanoparticle
The investigation of the effects of pre-irradiation annealing procedures on thermoluminescence dosimetric properties of different natural samples
Many thermoluminescence properties of dosimetric minerals may be affected by external effects and environmental condition. Annealing is one of the most known external effects and has different process. As a result of annealing process, the defect distribution of a specimen can be altered and thereby its sensitivity changes. In spite of fact that standard annealing procedures exist for the dosimetric purposes of the synthetic materials, these can be different for natural minerals. As the thermoluminescence properties of different natural minerals are unequal, different thermoluminescence properties are observed for the same natural minerals collected in the different region of the world. Therefore, annealing may alter the thermoluminescence properties of each natural minerals, differently. This thesis reveals that how the thermoluminescence properties of different natural minerals are affected by different pre-irradiation annealing processes. The origins of natural minerals used in this thesis were different and obtained from the different regions of Turkey. The thermoluminescence properties of four different natural minerals which are calcite minerals in sand used in making roasted chickpea, fluorapatite minerals in tooth enamel, plagioclase minerals in basaltic rocks and biogenic minerals in seashell have been studied under different thermal treatments.
Neutron halo and related structure in light nuclei
The works appeared recently dealing with exotic halo nuclei have displayed striking variations in nuclear shell structures and revealed the emergence of novel magic numbers unlike the stable nuclei. One of the significant reasons for these variations is the effect of tensor forces on nuclear structures, which has been reviewed in this report. Also, with the consideration of three-body nuclear forces, the known dramatic peculiarity over the oxygen isotopes has been debated to clarify why is the heaviest bound oxygen isotope. Finally, we focus at loosely bound neutron states within the frame of light halo nuclei to grasp why the weak binding plays a crucial role in observing the change in energies of lowest states. Keywords: Exotic nuclei, neutron-halo nuclei, , nuclear tensor force, three-body interaction force, binding energy
Investigation of thermoluminescence (TL) retrospective dosimetric properties of silicon carbide (sic) used in industry applications
During a nuclear accident or violent terror attack the dose measurement was not easily done at this moment because the data is not available to decide correct value of dose in the contaminated area. One of the alternative solution is by using retrospective dosimetry as a tool of accidental dosimetry for dose estimation. And many objects of the contaminated area are applicable as retrospective dosimeters. Although many electronic devices today are based on pure silicon substrates, a number of other substrates are used in various applications. SiC has been found to be widely useful as a substrate and wide band gap semiconductor in, high-temperature, high-frequency, and high-power electronic devices, as well as in short wavelength, radiation resistant optoelectronic devices. The aim of this study was to discuss the thermoluminescence (TL) properties of silicon carbide (SiC) used in industry applications for retrospective dosimetry purposes. Basic TL properties of these materials (e.g. dose response, heating rate, fading effect and reproducibility) have also been investigated.
Evaluation of the accuracy and efficiency of the in vivo dosimetry systems for whole brain cancer patients
In external beam radiotherapy quality assurance is carried out on the individual components of the treatment chain. The patient simulating device, planning system and linear accelerators are tested regularly according to set protocols developed by national and international organizations. In-vivo dosimetry measures the dose to the target volume through indirect measures therefore the most likely method for picking up errors which might occur earlier in the chain. In vivo dosimetry, using diodes or thermoluminescent dosimeters (TLDs) is performed in many radiotherapy departments to verify the dose delivered during treatment. In vivo dosimetry is applied to evaluate the delivered dose to critical organs or in complex geometries where the dose is hard to predict from the treatment. The aim of this study was to verily the response of TLDs type (LiF) use in radiotherapy, using Thermoluminescence detectors to establish calibration procedure for TLDs and to evaluate admission dose obtained by the treatment planning system with measured dose.
The investigation of thermoluminescence intensity-dose response relation of the tooth enamel at different annealing temperatures
Thermoluminescence (TL) is the natural light phenomenon emitted from an insulator or wide band gap semiconductor after absorbing some energy from an external radiation source when it is stimulated by thermal excitation. Tooth enamel is the hardest part of tooth and protects the dentine. In terms of its weight, it consists of 95% inorganic minerals, 1% organic minerals, and 3% water. Fluorapatite Ca5F(PO4)3 is an important mineral in tooth enamel. Due to the fact that the effective atomic number of fluorapatite is nearly the same with human calcified tissues, it is a candidate of important thermoluminescence dosimeter (TLD) material. In this thesis, thermoluminescence (TL) intensity-dose response relation of fluorapatite mineral in tooth enamel under the different annealing temperatures were investigated and then analyzed its thermoluminescence glow curve peaks with a computer programs. This study reveals that the fluorapatite mineral extracted from tooth enamel shows TL properties. Annealing of the sample at different temperatures affects the TL output- dose response relation. A good linearity in dose response is observed in the samples annealed at 400 oC and 700 oC. And also, dose variation differently changes the trap positions at different annealing temperature.
Acoustical analysis and evaluation of cultural centers at Gaziantep University
Gaziantep, one of the oldest cultural centers in the Southeastern Anatolia Region, is located on the historical Silk Road. The main objective of this thesis is the analysis of current acoustical performance of Gaziantep University Auditorium and Atatürk Cultural Center which are the most important centers of these cultural activities to carry out. Despite the fact that both salons are used as multipurpose halls, there are no variable panels (or any acoustic solution) in volume. In this context, the assessments were made on the basis of subjective and subjective parameters based on room acoustics. The measurements of the obtained acoustic parameters were compared with the results obtained in the ODEON acoustic analysis program for accuracy. The results were analyzed on the basis of the room acoustic criterion of multipurpose halls, and some suggestions were made to improve the acoustical performance of both halls.
Investigation of thermoluminescence response of TLD-600 and TLD-700 dosimeters to neutron+gamma and beta radiations
In this study some of the thermoluminescent properties such as glow curve structure, relative thermoluminescence sensitivity, dose response linearity of lithium fluoride thermoluminescent dosimeters TLD-600 (6LiF: Ti, Mg) and TLD-700 (7LiF: Ti, Mg) were investigated after irradiation 252Cf neutron+gamma and90Sr-90Y beta sources at room temperature and then with obtained results were compared. The kinetic parameters of TL glow peaks namely the order of kinetics (b), activation energy (Ea) and the frequency factor (s) of these dosimeters have also been obtained using the computerized glow curve deconvolution (CGCD) program. In addition, the effect of heating rate on the TL glow curves of dosimeters has been investigated. They were found that the maximum TL glow peak intensities and the total area under the glow curves of both dosimetries are decreasing with increasing heating rate. There is no good agreement with the kinetic parameters calculated by CGCD program for both radiation sources.
Investigation of thermoluminescence properties of natural calcite (CaCO3) from Iraq
Thermoluminescnce characteristics for natural calcite sample has been investigated in this study after irradiated by beta source for dose level from 2.4 Gy to 2.3 kGy. Computer glow curves deconvolution (CGCD) and Peak shape (PS) methods are used to estimate E (activation energy), s (attempt-to-escape frequency factor) and b (kinetic order). Calcite sample which used in this study where collected from DOHUK city – north of Iraq show two peaks follow Beta irradiation for dose levels which were applied in this study, peak 1 at 189 0C and peak 2 at 280 0C. Benefits of studying dose response and fading are to measure irradiation dosimetry and archeological dating. Calcite sample was irradiated and stored in dark box at room temperature and read out, after three weeks peak 1 completely disappeared, after 1 hour of stored peak 1 down to half of original intensity value, this means that this sample loses radiation fairly quickly.
Experimental performance investigation of electrical energy production system by using vertical barrel of two and five blades from wind energy in Gaziantep condition
Vertical-axis wind turbines (VAWTs) possess several advantages over the conventional horizontal-axis type. Savonius turbines are drag-based routers which operate due to a pressure difference between the advancing and retreating blades. These turbines are simpler in design, less expensive to install, non-dependent of wind direction, and more efficient at lower wind speeds. This makes it suitable for generating electricity in many countries. This work is a study of the performance of the Savonius rotor which contains two and five blades made from barrels of oil under the normal weather conditions of the Turkish city of Gaziantep. This rotor has the best self-starting at low wind speed, under any load generator. Where begins rotation of 20 RPM at 2 m/s wind velocity. We also find the maximum power coefficient at the tip speed ratio and the amount of voltages generated by the generator at different wind speeds to both types and know which one has the best performance. Key Words: Vertical axis wind turbine, savonius, electric power, voltage.
Calculation of critical mass for fission chain reaction
Neutrons at certain energies colliding with fissile nuclei may cause them to undergo fission reaction by splitting into fragments at different masses. Since new neutrons are produced at the end of each fission reaction, a certain amount of fissile material in any type of nuclear reactor core is required for a sustainable chain reaction by these neutrons. It is necessary to determine the amount of mass required for a sustainable fission chain reaction since the procedure is completely random for neutrons to strike target nuclei. It is known that the critical mass is the smallest amount of fissile material needed for such a sustainable nuclear chain reaction in any system of geometry. It is obvious that the critical mass of a fissionable material depends upon its nuclear properties such as its fission cross-section, density, shape, enrichment, purity, etc. In this study, the solutions of the steady-state one group diffusion equation are firstly analytically obtained and then compared with numerical results of the Monte Carlo Method coded to calculate the critical mass for three basic geometries. The survival fraction value, f_s (which is also called as the multiplication factor, k) is calculated for the criticality condition for these geometries and the results are tabulated for each one. Our numerical calculations by Monte Carlo Method show that the minimum critical mass is obtained in the case of spherical shape of fuel element for which the analytical solutions are also in aggrement.
Modelling of novel bismide alloys for optoelectronic devices
The purpose of this thesis work is to investigate the electronic band structures of InAsBi/InAs, InPBi/InP, InSbBi/InSb and GaAsBiN/GaAs III-V materials by means of using model calculations. When bismuth and nitrogen atoms are incorporated into a III-V binary host semiconductor, bismuth and nitrogen impurity atoms occupy at localized energy levels which lies inside or close to the valence and conduction band, respectively. These localized impurity states interact with the extended valence and conduction band states of host alloy. This interaction causes a splitting in each of these band states of the light hole, heavy-hole, split-off band and conduction subbands into subbands of E+ and E- energy levels. The incorporation of dilute bismides and nitrides into host materials cause a reduction in band gap with increasing bismuth and nitrogen concentration, an increase in spin-orbit splitting energy with increasing bismuth concentration. These major modifications in band structure tends to eliminate or suppress optical loss mechanism, such as Auger recombination and Intervalence band absorption. Our theoretical analysis is based on the conduction band anti-crossing, C-BAC, model for incorporation of dilute nitrides and the valence band anti-crossing, VBAC, model for incorporation of dilute bismides to model the restructuring of valence and conduction bands.
Investigation of thermoluminescence properties of calcite mineral conducted by bacterial calcium carbonate (CaCO3) precipitation in organic soil
The object of this study is investigation of thermoluminescence (TL) properties which are dose response, heating rate, reproducibility and fading of calcite mineral conducted by bacterial calcium carbonate (CaCO3) precipitation in organic soil. The TL glow curves of the irradiated samples by using beta source 90Sr-90Y (≈ 0.04 Gy/s) were obtained for different dose levels between 2.4 Gy and 6.9 kGy. Trap parameters such as trap depth (Ea) and kinetic order (b) were obtained by using computerized glow curve deconvolution (CGCD) method, also the peak integral (n) was evaluated from TL signal by choose a specific dose at with 1oC/s heating rate β. The results for calcite show a clear TL glow curve with four main peaks located around 90, 140, 210 and 240 oC and good TL properties with good reproducibility, wide linear dose response and good fading. A good linearity behavior observed for the dose–response between 140 Gy and 2.3 kGy for the peaks 210 oC and 240 oC. The dosimetric peaks located between 200 and 250 oC are not affected by the storage time. The kinetic parameters of traps are calculated for two main peaks which located around 88 and 208 oC, the trap depth varies between 0.74 - 0.82 eV and 0.83 - 0.88 eV, kinetic order (b) varies between 1.24 -1.5 and 1.4 -1.5, respectively.
On the prompt fission neutron energy distributions
Prompt fission neutron energy spectrum (PFNS) from spontaneous fission of 240Pu (sf) and 242Pu (sf) is calculated and compared quantitatively with the experimentally measured data. Calculations were done with three different methods; the first method is based on neutron's average center of mass kinetic energy, for the second fission fragment excitation energy distribution was used, and for the third method standardization of 252Cf (sf) was preferred. In each method aim is to calculate nuclear temperature parameters of light and heavy fission fragments. The last method has also been used in this thesis to calculate several crucial parameters of some well-known fissile nuclei, such as neutron average center of mass energy, excitation energy and multiplicity. We have shown that all calculations well describes the observed data.
Effect of temperature on photovoltaic panel efficiency
Today, the needs of societies are mostly provided by technology and the new generation technology has entered every part of our lives. New generation technology has created a high level of energy requirement. Many energy sources have started to be depleted rapidly and today's society has turned to search for renewable energy sources. The sun is the basis of all energy sources, and many solar energy systems especially photovoltaic panels have been developed. Photovoltaic panels are the system that converts light from the sun into direct electrical energy. In the photovoltaic panel system, there is a high amount of energy losses during the conversion of the incoming light to electricity. In this study, the negative effect of temperature on photovoltaic panels was investigated and in order to eliminate this effect, behind the panel was applied with water cooling method. Power comparison is carried out between normal solar panel and water cooled solar panel. It was shown that the output power in the water-cooled system is higher than the normal panel. Key word : Photovoltaics, Cell Efficiency, Solar system, Cell temperature
The investigation of thermoluminescence properties ofdental ceramics
Dental ceramics taken from humans who are potentially exposed to radiation, are commonly used as retrospective dosimetry for quick and reliable dose estimations due to nuclear power plants that are close to settlement of people. Nowadays most people have a dental restoration for the compulsory health problem and aesthetic beauty. Moreover dental restorations are usually applied to the front teeth, it can be considered that the radiation directly interact with the material. Therefore, dental ceramics could be potentially used for retrospective dosimetry purposes since allows a quick and reliable dose assessment in case of nuclear accident or bad use of a nuclear attack. Therefore, dental ceramics that used in restoration of human teeth as an accident dosimetry by thermally stimulated luminescence method have been investigated in this study. Glass ceramic, lithium disilicate glass ceramic and feldspathic dental ceramic which used in this study were obtained from Vivadent ivoclar, Sweden and Turkey, respectively. The aim of the study is to investigate the thermoluminescence dose response, the effects of heating rates on the thermoluminescence characteristics, the stability of the dental ceramics with respect to the cycle of measurement and also fading properties of dental ceramics. Finally we compared the samples with respect to their TL characteristic properties to choose the most suitable dosimetric ceramic.
Tactile, embedded, audible sensation system for blind people
ABSTRACT TACTILE, EMBEDDED, AUDIBLE SENSATION SYSTEM FOR BLIND PEOPLE KARAOĞLAN, Kemal M.Sc. in Physical Engineering Supervisor: Prof. Dr. Zihni ÖZTÜRK April 2019 59 pages It is not possible for visually impaired individuals to move around without getting support from another person when they go out of their houses and perceive their surroundings. He gets help to get to where he is going in the city and in all settlements, he does not know which street, street, building or institution he is when he comes to a door or entrance, when he comes to a street. For this reason, the visually impaired individual is guiding another person, which limits the individual life opportunities of the visually impaired individual. For this purpose, dots called the sensitive line, which are developed for this purpose, are not sufficient but only allow the visually impaired person to follow a line and realize that the end of the line is at the end of the line. You can not find out where you are walking, where you will be at the end of your walk, where you end up, and where the junction is. For this reason, he needs a support or knowledge again.This thesis study examines a system that allows the visually impaired individuals to use and perceive the place to go. It consists of a cane, wireless glasses and earphone, a movable cane carried by the user, and an informative unit which can be placed on the surface, buried in the pavement walkway and used indoors and outdoors Key Words: Audible eye, Sensitive lines, Voice relief lines, Voice access, Visual impairment orientation
A study on the computerized tomographic x-Ray radiation on duration and Ramsay scale of sedation
the effect of CT
Structure, composition and corrosion studies of Zn, Cu, Sn and their alloys electrodeposited from a deep eutectic solvent
In this thesis, platinum and steel were coated with metals (Cu, Zn and Sn), binary alloys (Cu-Zn, Cu-Sn and Zn-Sn) and a triple alloy (Cu-Zn-Sn) by electrochemical method. The corrosion behaviour of these films were investigated in 3.5% NaCl solution. Chlorine chloride-ethylene glycol based ionic liquid was used for electrodeposition of metals and alloys. The plating process was carried out on platinum and steel by a three electrode system by applying constant potential. As metals/alloys were electrodeposited potentiostatically, chronoamperometric graphs of deposition were obtained. The resulting coated samples were analyzed by SEM, XRD/EDAX and optical microscope. Potentiodynamic polarization (Tafel Plot) was applied to understand the corrosion mechanism of uncoated and coated samples in 3.5% NaCl. Corrosion current of Zn is lower than the other two metals and among these three metals zinc has passivation behaviour. Corrosion behaviours of binary alloys (Cu-Zn, Cu-Sn and Zn-Sn) and ternary Cu-Zn-Sn were examined. Generally, corrosion resistivity of binary alloys on Pt is higher than that of metals on Pt. It could be said that Zn dominates corrosion current of alloys deposited from a deep eutectic solvent. Corrosion resistivity of binary alloys on steel is close to each other. Corrosion current density of binary alloys on Pt is approximately 10 times more resistive than bare steel. The polarisation curve of the ternary alloy of Corrosion resistivity of ternary alloy (Cu-Zn-Sn) on Pt is eight times greater than bare steel. Alloys could be electrodeposited on steel to prevent corrosion.
Investigation of the effects of beta rays on phosphorescent materials
The aim of this thesis is to investigate the effects of beta radiation on phosphorescent materials. Nowadays phosphorescent materials are used to get the production of more efficient beta voltaic nuclear batteries. They convert the kinetic energy of particles to fluorescence by using phosphor material and then to convert electricity via photovoltaic cell. We have researched the effects of beta particles by analyzing the parameters such as range and generation rate for different type of phosphorescent materials that are used in nuclear batteries. These parameters effectively improve the output performance and energy conversion efficiency in nuclear batteries.
Design and production of a portable solar test device to test, the characteristic values and the classification of solar panels
The electric output performance of crystalline silicon and thin film PV modules are generally measured under standard test conditions (STC), ensuring a relatively independent comparison and output evaluation of different solar PV modules. STC is an industry-wide standard to indicate the performance of PV modules and specifies a cell temperature of 25°C and an irradiance of 1000 watt/m2 with an air mass 1.5 (AM 1.5). These correspond to the irradiance and spectrum of sunlight incident on a clear day upon a sun-facing 37 degrees tilted surface with the sun at an angle of 41.81 degrees above the horizon. This condition approximately represents solar noon near the spring and autumn equinoxes in the continental United States with surface of the cell aimed directly at the sun. However, these conditions are rarely encountered in the real-world. In this study, DC voltmeter and DC ammeter has been used which has RS485 communication protocol. Open circuit voltage (Voc) , short circuit current (Isc), maximum voltage under load (Vmp) and maximum current under load (Imp) of different power solar panels have been measured after that compared with label values. Additionally, Open circuit voltage (Voc) , short circuit current (Isc), maximum voltage under load (Vmp) and maximum current under load (Imp) values have been transferred to touchable Liquid crystal display (LCD) with the aid of RS485 protocol for user benefit. With aid of this portable test device also can measure personal solar panel power as small scale project and detect defect modules of in photovoltaic farm as large project. Key Words: PV Modules, Testing Measurement and Classification System for the PV Panels
Investigation of factors influencing the efficiency of nuclear batteries
In this thesis, the conversion of the kinetic energy of beta particles emitted from a radioactive isotope to electricity is investigated by using the direct and indirect conversion methods. In the experimental part, analysis of the effects of low-activity radiation from Pm147 and Sr90 beta sources, two different phosphors and graphene on Si photovoltaic cell is performed. Phosphor layers with different mass thicknesses are prepared from ZnS:CuCl and SrAl2O4:Eu2+,Dy3+ phosphor powders. The electrical performances of direct and indirect nuclear battery models are analyzed by measuring short-circuit current and open-circuit voltage. Furthermore, the time-dependent variation of the short-circuit current during the beta irradiation is researched. The most efficient battery model is determined as Pm147/SrAl2O4:Eu2+,Dy3+/PV cell. In the theoretical part, betavoltaic battery designs are modeled using the p-n homojunctions, p-n heterojunctions, and Ni63, Pm147 beta sources by considering the parameters affecting the efficiency. A theoretical investigation of the electrical performances has been carried out on Si, GaP, GaN, GaP-Si, and GaN-Si betavoltaic batteries. In addition, the effects of doping concentration and junction depth on the maximum power are examined. The heterojunction photovoltaic cells are preferred to increase the collection efficiency and the power in the betavoltaic battery according to our calculations. By optimizing the doping concentration and junction depth, high-efficient heterojunction betavoltaic batteries are achieved.
Measurement of the inclusive production of the d*0 (2007) meson in hadronic z decays with the aleph detector at the lep collider
A measurement of the inclusive production rate of the charmed D*0 (2007) meson in hadronic Z decays is performed using data from the ALEPH detector at the LEP collider. A total of 3,239,746 hadronic events are selected from data recorded by ALEPH from the 1991 to 1995 running periods. Decays of D*0 D0pi0 are reconstructed for x_E >= 0.3 where x_E = E_D*0 / Ebeam. The average D*0 multiplicity per hadronic event is evaluated to be: =0.289 +- 0.031 +- 0.067 +- 0.009 where the first error is statistical and the second is systematic. The third error is from the extrapolation to x_E = 0. The rates and differential cross-sections are compared with Monte Carlo model predictions. The signal significance is improved explicitly by applying machine learning algorithms based on Multi Variate classification methods of artificial intelligence applications.
The investigation of the effects of velocity dependent potential in the solution of wave equation
ABSTRACT THE INVESTIGATION OF THE EFFECTS OF VELOCITY DEPENDENT POTENTIAL IN THE SOLUTION OF WAVE EQUATION BERK ATEŞ, Yıldız Ph.D in Engineering Physics Supervisor: Prof. Dr. Eser OLĞAR February 2020 88 pages In this thesis, the effect of the velocity-dependent potential is taken into consideration in order to obtain the solution of Schrödinger equation (SE) for different physical potentials. By choosing form factors as three different cases such as ε(r)=γρ_0,ε(r)=γr and ε(r)=γr^2, the velocity-dependent potential is determined and the energy eigenvalues and eigenfunction are obtained for any quantum numbers n and l. During all calculations, the well-known method Nikiforov-Uvarov (NU) method is used. It is seen that by taking γ=0, the obtained results are reduced to results of velocity-independent potential case which are in good agreement with those of in literature. The variations of energy eigenvalues are tabulated and graphed with respect to quantum numbers n and l. Key Words: Velocity-Dependent Potentials, Analytical Solution, Numerical Solution, Nikiforov-Uvarov Method.