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- Chalcogenide glasses (3)
- Cosmic ray (3)
- Diurnal (2)
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- Photoconductivity (2)
- Semi-diurnal (2)
- 2212 phase (1)
- A-Si:H (1)
- Ab initio. (1)
- Activation energy of crystallization. (1)
- Activation energy of glass transition. (1)
- Admittance spectroscopy (1)
- Amorphous Thin films. (1)
- Anisotropy (1)
- Anisotropy and solar poloidal magnetic field. (1)
- Antireflection coatings (1)
- BPW34 (1)
- BSCCO (1)
- BSCCO superconductors (1)
- Bound states. (1)
- Breit equation (1)
- CIGS (1)
- Carbon nanotube (1)
- Chalcogenide Glasses (1)
- Chalcogenide-glasses; gamma-ray effects; visible-spectra (1)
- Chemical bath deposition technique; Bismuth oxy iodide; poultry protection and warming coating; solar control and antireflection coatings and solar cells. (1)
- Coevaporation (1)
- Composite materials (1)
- Conducting Polymers (1)
Articles 1 - 30 of 45
Full-Text Articles in Physics
A Solution To Symmetric Teleparallel Gravity, Muzaffer Adak, Özcan Sert
A Solution To Symmetric Teleparallel Gravity, Muzaffer Adak, Özcan Sert
Turkish Journal of Physics
Teleparallel gravity models, in which the curvature and the nonmetricity of spacetime are both set zero, are widely studied in the literature. We work a different teleparallel theory, in which the curvature and the torsion of spacetime are both constrained to zero, but the nonmetricity is nonzero. After reformulating the general relativity in this spacetime we find a solution and investigate its singularity structure.
Investigation Of The Intergrain Junctions Of Polycrystalline Htsc In Rotating Weak Ac Magnetic Fields, Ioseb R. Metskhvarishvili, Magda R. Metskhvarishvili, Luiza Khorbaladze, Mikheil Elizbarashvili, Zaur Miminoshvili, Larisa Nekrasova
Investigation Of The Intergrain Junctions Of Polycrystalline Htsc In Rotating Weak Ac Magnetic Fields, Ioseb R. Metskhvarishvili, Magda R. Metskhvarishvili, Luiza Khorbaladze, Mikheil Elizbarashvili, Zaur Miminoshvili, Larisa Nekrasova
Turkish Journal of Physics
YBa_2Cu_3O_y polycrystalline superconductor has been studied in weak rotating ac magnetic fields with existence of constant dc field. Measurements were carried out in various temperature intervals, and in various variable and constant fields. Results of our experiments are in good agreement with the isotropic model.
Determination Of Defect Distribution In A Ga-Rich Zno/Cds/Cu(In,Ga)Se_2 Solar Cell By Admittance Spectroscopy, Habi̇be Bayhan
Determination Of Defect Distribution In A Ga-Rich Zno/Cds/Cu(In,Ga)Se_2 Solar Cell By Admittance Spectroscopy, Habi̇be Bayhan
Turkish Journal of Physics
This article presents a study on the energy distribution of defects in efficient thin film ZnO/CdS/Cu(In,Ga)Se_2 heterojunction solar cell by the use of admittance spectroscopy. The capacitance spectra of the device has been analyzed using a model based on the existence of a homogeneous distribution of bulk acceptors in the absorber Cu(In,Ga)Se_2 layer. This model reveals an emission from a distribution of hole traps centered at an activation energy of about 300 meV with a defect density of 1.2 \times 10^{17} eV^{-1} cm^{-3}. The band gap of the absorber layer is estimated to be about 1.46 eV which corresponds to …
Magnetic Behaviour Of ``Lithiated'' Fe_2tio_5, M. A. Madare, S. V. Salvi
Magnetic Behaviour Of ``Lithiated'' Fe_2tio_5, M. A. Madare, S. V. Salvi
Turkish Journal of Physics
Fe_2TiO_5 shows a spin glass transition at 53 K and is mainly known for its semiconducting nature. A `LiAl' pair is incorporated in Fe_2TiO_5 by high temperature solid-state reaction. Fe_2TiO_5 + xLiAlH_4 \frac{1000 °C}{24 hrs in atmosphere} \to Fe_2Ti_{1-x} (LiAl)_xO_5 x < x The presence and quantity of ``LiAl'' is confirmed by Inductively Coupled Argon Plasma (IACP) technique. The crystalline geometry is determined by X- ray diffraction and Fourier Transform Infrared (FTIR) spectroscopy of powders. It remains orthorhombic pseudobrookite. Certain reflections of Fe_2TiO_5 are observed to enhance progressively with the content of ``LiAl''. The magnetic hysteresis parameters are observed to depend on the content of ``LiAl''. Initial susceptibility and permeability are measured as a function of temperature. The magnetic order is discussed and explained. It is concluded that the pseudobrookite possesses a `spinel like network', which is strengthened by incorporation of ``LiAl''. It produces a weak long-range ferrimagnetic order in place of short-range antiferromagnetic order. Possible applications are discussed in the text.
New Phases Of Ybacugeo Superconductors Identified From X-Ray Diffraction And Infra-Red Absorption Measurements, Ahmed Abo-Arais, Mohamad Ahmad Taher Dawoud
New Phases Of Ybacugeo Superconductors Identified From X-Ray Diffraction And Infra-Red Absorption Measurements, Ahmed Abo-Arais, Mohamad Ahmad Taher Dawoud
Turkish Journal of Physics
X-ray powder diffraction patterns and infra-red absorption spectra have been evaluated and analysed for the Y_1 Ba_2 Cu_3 O_{7-\delta} - Ge_x compound samples prepared by the solid state reaction with x values ranging from 0.0 to 1.13. All samples show bulk superconductivity above liquid nitrogen temperature using the levitation test (Meissner effect). Samples with Ge content up to x = 0.2 have offset T_c between 83K and 92K while the sample with x = 1.13 shows semiconducting behavior above 100K. As a result of the solid state interaction between YBCO and Ge, new phases are observed and determined, mainly three …
Design And Preparation Of Antireflection Films On Glass Substrate, Muhammad Hammad Asghar, Muhammad Bilal Khan, Shahzad Naseem, Zubair Ahmad Khan
Design And Preparation Of Antireflection Films On Glass Substrate, Muhammad Hammad Asghar, Muhammad Bilal Khan, Shahzad Naseem, Zubair Ahmad Khan
Turkish Journal of Physics
Antireflection coatings (ARC) have been modeled and prepared experimentally for optical and electro-optical applications in the visible spectrum (0.4--0.7 \mu m) to reduce reflections from the surface of glass. Reflection of BK7 bare glass substrate varies from 3.5 to 6.0% over the desired spectrum. This value is reduced reasonably by integrating multilayer thin films, based on dielectric materials, behaving as ARC. Three different three-layer configurations are deposited on glass substrate. The reflection profiles of theoretical and experimental curves are compared and analyzed to demonstrate the use of these multilayered structures. The physical parameters and deposition conditions of the three configurations …
Cosmic Ray Diurnal Anisotropy Related To Solar Activity, Rajesh K. Mishra, Rekha Agarwal Mishra
Cosmic Ray Diurnal Anisotropy Related To Solar Activity, Rajesh K. Mishra, Rekha Agarwal Mishra
Turkish Journal of Physics
The occurrence of a large number high amplitude event (HAE) of cosmic ray diurnal anisotropy during 1981--1994 has been examined as a function of solar activity. The high amplitude days with the time of maximum in the corotational/azimuthal direction do not indicate any significant correlation with solar activity. Our observations suggest that the direction of the anisotropy of HAE events contribute significantly to the long-term behaviour of the diurnal anisotropy. The occurrence of HAE is dominant during sunspot maximum as well as sunspot minimum.
Modeling Global Solar Radiation For A Tropical Location: Onne, Nigeria, Louis E. Akpabio, Sunday O. Udo, Sunday E. Etuk
Modeling Global Solar Radiation For A Tropical Location: Onne, Nigeria, Louis E. Akpabio, Sunday O. Udo, Sunday E. Etuk
Turkish Journal of Physics
Monthly average daily values of clearness index and relative sunshine over a period of sixteen years, using quadratic form of the Angstrom-Prescott model have been developed to estimate global solar radiation at Onne (Lat. 4° 46' N, Long. 7° 10' E), a tropical location. The predictive efficiencies of the models are also compared with those developed for the Nigerian environment, and those which are believed to be applicable globally. The applicability of the developed equations was tested in terms of mean percentage error (MPE), mean bias error (MBE) and root mean square error (RMSE).
A Study On Breit Interaction Through Heavy Mesons Spectra, L. I. Abou-Salem, M. S. M. Nour El-Din, M. M. Moussa
A Study On Breit Interaction Through Heavy Mesons Spectra, L. I. Abou-Salem, M. S. M. Nour El-Din, M. M. Moussa
Turkish Journal of Physics
In the present work the adequacy of the complete Breit interaction terms in describing the strong interaction can be tested through studying c\bar{c} and b\bar{b} spectra. Breit equation is solved using the complete Breit interaction form. The Breit equation can be transformed into three categories of differential equations according to the spectroscopic signature of the different states. The resonance masses of c\bar{c} and b\bar{b} states are calculated to order \alpha^4. One can see a good agreement between our results and the corresponding experimental data in all considered states.
Study Of Pseudorapidity Distributions Of Shower Particles Emitted In Interactions Of Nuclei With Emulsion At 4.1- 4.5 A Gev/C, Sakina Fakhraddin
Study Of Pseudorapidity Distributions Of Shower Particles Emitted In Interactions Of Nuclei With Emulsion At 4.1- 4.5 A Gev/C, Sakina Fakhraddin
Turkish Journal of Physics
The pseudorapidity distributions of shower particles in interactions of 4.5 A GeV/c ^{12}C, ^{16}O, ^{28}Si and ^{22}Ne at 4.1 A GeV/c with emulsion have been presented. The dependence of these distributions on the target nuclei (AgBr and CNO) have been investigated. The energy density for ^{24}Mg--Pb interactions is calculated using the Bjorken model.
Microstructure Characterization Of Znfe_{2-X}M_{X}O_{4} (M = Bi, Y And X = 0.1, 0.2) Ferrites By The Rietveld Refinement, Mansour Al-Haj
Microstructure Characterization Of Znfe_{2-X}M_{X}O_{4} (M = Bi, Y And X = 0.1, 0.2) Ferrites By The Rietveld Refinement, Mansour Al-Haj
Turkish Journal of Physics
The microstructure of the ferrites was analyzed by the Reitveld refinement method. The Bi-containing ferrites revealed a decrease in the lattice parameter as the Bi^{3+} concentration is increased, due to the distortion of the ferrite lattice. There was a minor distortion in the ZnFe_{1.9}Y_{0.1}O_4 ferrite lattice. A minor yttrium oxide phase coexisted with the ZnFe_{1.8}Y_{0.2}O_4 spinel phase.
Composition Dependence Of Photoconductivity In Amorphous Thin Films Of Se_{.80-X}Te_{.20}Ge_X, Deepak Kumar, Santosh Kumar
Composition Dependence Of Photoconductivity In Amorphous Thin Films Of Se_{.80-X}Te_{.20}Ge_X, Deepak Kumar, Santosh Kumar
Turkish Journal of Physics
The present paper reports the dependence on composition of photoconductivity in vacuum evaporated thin films of amorphous Se_{.80-x}Te_{.20}Ge_x (x = .05, .10, .15 and .20). Temperature dependence of conductivity in dark as well as in presence of light show that conduction is through a thermally activated process in both cases. The activation energy is found to decrease with increase in light intensity, indicating shift of the Fermi level with intensity. A correlation between activation energy and the pre-exponential factor is observed in all the compositions, which could be fitted to the Meyer-Neldel rule. Measurements on the dependence of photoconductivity on …
Low Frequency Dispersion In Non-Conducting Contacts In Humidity, Altaf Husain, S. Shakeel Ahmed
Low Frequency Dispersion In Non-Conducting Contacts In Humidity, Altaf Husain, S. Shakeel Ahmed
Turkish Journal of Physics
To develop an enhanced understanding of an aspect of the charge transport mechanism in systems composed of solid-solid insulating contacts, the dynamic dielectric response of sand grains and of silica-silica rod contacts was investigated at dry and at 97% relative humidity (RH), in the frequency range 10^{-2} to10^5 Hz. In dry atmosphere no appreciable amount of conductivity is observed, while in humidity the response follows a strongly dispersive behaviour. Sharp rise in capacitance gives a clear evidence for the storage of charge in the transport process. Collectively, the conductance of the sand grains increases super-linearly with the number of contacts …
Optical Characterization Of Chemical Bath Deposited Bismuth Oxyiodide (Bioi) Thin Films, F. I. Ezema
Optical Characterization Of Chemical Bath Deposited Bismuth Oxyiodide (Bioi) Thin Films, F. I. Ezema
Turkish Journal of Physics
Thin films of Bismuth oxyiodide (BiOI) were deposited, using chemical bath deposition techniques. The films were characterized using energy dispersive x-ray fluorescence (EDXRF) and Fourier transform infrared (FTIR) spectroscopy for chemical composition, and a spectrophotometer for the analysis of spectral absorbance / transmittance / reflectance. Deposited film thickness ranged between 0.115 and 0.140 \mu m. The optical properties deduced from the spectral absorbance / transmittance / reflectance include the maximum values of the refractive index n that ranged between 2.62 and 2.64, the extinction coefficient k ranged between 25.84 \times 10^{-3} and 42.92 \times 10^{-3} while the Optical conductivity \sigma …
Electrical And Structural Properties Of Ex-Situ Annealed Superconducting Bi_2sr_2cacu_2o_8 Thin Films Obtained By Coevaporation Of Components, Necdet Baştürk
Electrical And Structural Properties Of Ex-Situ Annealed Superconducting Bi_2sr_2cacu_2o_8 Thin Films Obtained By Coevaporation Of Components, Necdet Baştürk
Turkish Journal of Physics
Bi_2Sr_2CaCu_2O_8 system superconducting thin films were obtained by synchronized deposition of Bi, Cu, CaF_2 and SrF_2 components onto cleaved MgO (100) single crystal substrates after annealing in the temperature range 600--840 °C. The films were annealed in H_2O and O_2, then dry O_2 atmosphere for the removal of fluorine from the structure and to attain superconducting properties. X-ray powder diffraction patterns were used to characterize the obtained film structure. The films were observed to grow along c-axis perpendicular to the substrate surface with the identified reflection on the (00l, l = 6, 8, 10...) planes. The films having the critical …
Dielectric Relaxation In Glassy Se_{100 - X} Sb_X, N. Choudhary, A. Kumar
Dielectric Relaxation In Glassy Se_{100 - X} Sb_X, N. Choudhary, A. Kumar
Turkish Journal of Physics
Frequency and temperature dependence of dielectric constant \varepsilon' and dielectric loss \varepsilon'' are studied in glassy Se_{1-x} Sb_x (x = 0, 0.02, 0.04, 0.06, 0.08 and 0.10) in the frequency range from 1--10 kHz and in the temperature range 290 K to 360 K. The experimental results indicate that no dielectric dispersion exist in glassy Se in the operating range of frequencies. However, when Sb concentration increases in Se_{1-x} Sb_x (x = 0.02, 0.04, 0.06, 0.08 and 0.10) dielectric dispersion starts in the upper frequency and temperature range. The values of \varepsilon' and \varepsilon'', as functions of temperature and frequency, …
Electron-Deuteron Tensor Polarization And D-State Probability, A. K. A. Azzam, M. A. Fawzy, E. M. Hassan, A. M. Yasser
Electron-Deuteron Tensor Polarization And D-State Probability, A. K. A. Azzam, M. A. Fawzy, E. M. Hassan, A. M. Yasser
Turkish Journal of Physics
Electron-deuteron tensor polarization T_{21}(q) is calculated for thirty-three N-N local potential models. New relations have been found between the peak value of T_{21}(q) and some of the deuteron properties. An experimental value of deuteron D-state probability P_D = 5.9861\% \pm 0.2687\% is deduced.
Multiple Scale And Hamilton-Jacobi Analysis Of Extended Mathieu Equation, Özlem Yeşi̇ltaş, Mehmet Şi̇mşek
Multiple Scale And Hamilton-Jacobi Analysis Of Extended Mathieu Equation, Özlem Yeşi̇ltaş, Mehmet Şi̇mşek
Turkish Journal of Physics
In this study, we use perturbation approximations and semiclassical methods to investigate the boundary solutions of non-linear vibrating systems. The extended Mathieu Equation, related to the perturbed Van der Pol oscillator with periodic coefficients, is solved using multiple time scales. Then, using the Von Zeipel Method, which is based on the Hamilton-Jacobi theory, stability conditions are presented. It is shown that the stability boundaries are the same with those obtained by both methods.
Quantization Of Reparametrized Systems Using The Wkb Method, Khaled I. Nawafleh, Eqab M. Rabei, Humam B. Ghassib
Quantization Of Reparametrized Systems Using The Wkb Method, Khaled I. Nawafleh, Eqab M. Rabei, Humam B. Ghassib
Turkish Journal of Physics
The quantization of reparametrized systems is discussed using the WKB approximation. The Hamilton-Jacobi function, the equations of motion and the wave function---which the conditions constrain in the semiclassical limit---are determined. The success of this approach is then demonstrated for two applications. The first is an illustrative example of nonrelativistic dynamics. The second is the well-known motion of a relativistic particle in an external electromagnetic field.
Mössbauer, Infrared And X-Ray Studies For Ni_{0.5}Zn_{0.5}Cr_Xfe_{2-X}O_4 Ferrites, Mohamed Amer, S. Ata-Allah, T. Meaz, S. Aboul-Enein, M. Abd-El-Hamid
Mössbauer, Infrared And X-Ray Studies For Ni_{0.5}Zn_{0.5}Cr_Xfe_{2-X}O_4 Ferrites, Mohamed Amer, S. Ata-Allah, T. Meaz, S. Aboul-Enein, M. Abd-El-Hamid
Turkish Journal of Physics
Spinel ferrites of the system Ni_{0.5}Zn_{0.5}Cr_xFe_{2-x}O_4, 0 \le x \le 1, have been studied via Mössbauer, IR and X-ray spectra. Mössbauer spectra of the samples showed broad six-line patterns and a central paramagnetic phase. The spectra have been analyzed to two magnetic patterns, A and B, and two quadrupole doublets, C_A and C_B. The patterns A and C_A are assigned to Fe^{3+} ions at the tetrahedral A-sites and the patterns B and C_B to Fe^{3+} and Fe^{2+} ions at the octahedral B-sites. The deduced hyperfine interaction parameters; the isomer shifts, quadrupole splitting, outermost line widths, hyperfine magnetic fields and bulk …
Influence Of Solar Activity On Low Amplitude Cosmic Ray Diurnal Anisotropy, Rajesh K. Mishra, Rekha Agarwal Mishra
Influence Of Solar Activity On Low Amplitude Cosmic Ray Diurnal Anisotropy, Rajesh K. Mishra, Rekha Agarwal Mishra
Turkish Journal of Physics
A detailed study has been conducted on the occurrence of a large number of low amplitude events (LAE) of cosmic ray (CR) diurnal anisotropy during 1981--1994 as a function of solar activity. The low amplitude days with the time of maximum in the corotational/azimuthal direction do not indicate any significant correlation with solar activity. Our observations suggest that the direction of the anisotropy of LAE events contribute significantly to the long-term behaviour of the CR diurnal anisotropy. The occurrence of LAE is dominant during solar activity minimum years.
East-West And Radial Anisotropy In Cosmic Ray Modulation, Rekha Agarwal Mishra, Rajesh K. Mishra
East-West And Radial Anisotropy In Cosmic Ray Modulation, Rekha Agarwal Mishra, Rajesh K. Mishra
Turkish Journal of Physics
The cosmic ray (CR) data observed with the Deep River neutron monitoring station has been harmonically analyzed for the period 1964--95 to obtain the diurnal and semi-diurnal components of cosmic ray intensity on geomagnetically 60 quiet days. The annual diurnal anisotropy vectors have been resolved into two components: one along the 12-Hr direction, the radial anisotropy component; and the other along 18-Hr direction, east-west anisotropy component. It is observed that when the polarity of solar poloidal magnetic field (SPMF) in northern hemisphere (NH) is positive, the radial anisotropy component increases; whereas, the east-west anisotropy component decreases. This results in shifting …
Calorimetric Studies On Se_{0.68}Ge_{0.22}M_{0.10} (M = Cd, In, Pb) Chalcogenide Glasses, N. Mehta, P. Agarwal, A. Kumar
Calorimetric Studies On Se_{0.68}Ge_{0.22}M_{0.10} (M = Cd, In, Pb) Chalcogenide Glasses, N. Mehta, P. Agarwal, A. Kumar
Turkish Journal of Physics
Differential scanning calorimetry (DSC) is performed at different heating rates under non-isothermal conditions to calculate the activation energy of crystallization E_c for chalcogenide glasses Se_{0.68}Ge_{0.22}M_{0.10} (M = Cd, In and Pb) using the well known Kissinger's relation, Matusita-Sakka theory and the method of Augis-Bennett. The overall mean bond energy of these glassy alloys has been evaluated using theory of Tichy and Ticha. A good correlation has been found between E_c and . This indicates that the overall mean bond energy plays an important role in the thermal crystallization of chalcogenide glasses.
Dirac Sextic Oscillator In The Constant Magnetic Field, Ramazan Koç, Mehmet Koca
Dirac Sextic Oscillator In The Constant Magnetic Field, Ramazan Koç, Mehmet Koca
Turkish Journal of Physics
We introduce a Dirac equation which reproduces the usual radial sextic oscillator potential in the non-relativistic limit. We determine its energy spectrum in the presence of the magnetic field. It is shown that the equation is solved in the context of quasi-exactly-solvable problems. The equation possesses hidden sl_2-algebra and the destroyed symmetry of the equation can be recovered for specific values of the magnetic field which leads to exact determination of the eigenvalues.
Features Of Daily Variation In Cosmic Ray Intensity During High/Low Amplitude Events, Rajesh K. Mishra, Rekha Agarwal Mishra
Features Of Daily Variation In Cosmic Ray Intensity During High/Low Amplitude Events, Rajesh K. Mishra, Rekha Agarwal Mishra
Turkish Journal of Physics
A detailed study has been conducted on the long-term changes in the diurnal, semi-diurnal and tri-diurnal anisotropy of cosmic rays in terms of the high/low amplitude anisotropic wave train events (HAE/LAE) during the period 1981--94 using the neutron monitor data from the Deep River neutron monitoring station. In all, 38 HAE and 28 LAE cases have been studied. An inter-comparison of the first three harmonics during these events has been made so as to understand the basic reason causing the occurrence of these types of events. It has been observed that the phase of diurnal anisotropy shifts towards earlier hours …
Standard Ubv Observations At The Çanakkale University Observatory (Çuo), Hi̇cran Bakiş, Volkan Bakiş, Osman Demi̇rcan, Edwin Budding
Standard Ubv Observations At The Çanakkale University Observatory (Çuo), Hi̇cran Bakiş, Volkan Bakiş, Osman Demi̇rcan, Edwin Budding
Turkish Journal of Physics
By using standard and comparison star observations carried out at different times of the year, at Çanakkale Onsekiz Mart University Observatory, we obtained the atmospheric extinction coefficients at the observatory. We also obtained transformation coefficients and zero-point constants for the transformation to the standard Johnson UBV system, of observations in the local system carried out with the SSP5A photometer and T40 telescope. The transmission curves and the mean wavelengths of the UBV filters as measured in the laboratory appear not much different from those of the standard Johnson system and found inside the transmission curve of the standard mean atmosphere.
Some Physical Properties Of \Gamma Irradiated Ge_X(As_2te_3)_{100 - X} Chalcogenide System, Afaf Abdel-Aal, Bahiga Abdel-Hameed Mansour, Hoda Mohamed Eissa
Some Physical Properties Of \Gamma Irradiated Ge_X(As_2te_3)_{100 - X} Chalcogenide System, Afaf Abdel-Aal, Bahiga Abdel-Hameed Mansour, Hoda Mohamed Eissa
Turkish Journal of Physics
The effect of \gamma -radiation on the electrical conductivity, switching, and optical properties of the chalcogenide amorphous system Ge_x(As_2Te_3)_{100 - x} (where x = 0,1,5,10 atm %) have been studied. The results show that the radiation causes a shift of the optical gap,as well as a change in the electrical activation energy and the threshold voltage. As the \gamma -doses increase, the values of the allowed indirect optical energy gap E_{opt} for the different compositions decreases and the tail energy width increases.
Kinetic Parameters Of Glass Transition In Glassy Se_{1 - X}Sb_X Alloys, R. S. Tiwari, N. Mehta, R. K. Shukla, A. Kumar
Kinetic Parameters Of Glass Transition In Glassy Se_{1 - X}Sb_X Alloys, R. S. Tiwari, N. Mehta, R. K. Shukla, A. Kumar
Turkish Journal of Physics
Differential Scanning Calorimetry (DSC) is performed at different heating rates under non-isothermal conditions to study the glass transition kinetics of glassy Se_{1 - x}Sb_x (x = 0.02, 0.04, 0.06, 0.08 and 0.10) alloys. The activation energy of glass transition E_t has been calculated using the two different non-isothermal methods. One of the two methods is based on the theory of glass transition kinetics and structural relaxation as developed by Moynihan and other workers, while the other relation is well-known Kissinger's relation. The results show that the values of E_t determined from both the methods are in good agreement with one …
Photoconductivity Of Selenium And Sulphur Doped A-Si:H Thin Films, Sanjeev Kumar Sharma, Himanshu Gupta, Rajendra Kumar, Ram Mohan Mehra
Photoconductivity Of Selenium And Sulphur Doped A-Si:H Thin Films, Sanjeev Kumar Sharma, Himanshu Gupta, Rajendra Kumar, Ram Mohan Mehra
Turkish Journal of Physics
This paper presents a study of photoconductivity of S- and Se-doped a-Si:H as a function of composition and temperature. Temperature dependence of photoconductivity of the films was measured under the illumination of white light at 100~mW/cm^2. The room temperature photoconductivity for the same doping concentration of 10^{-4} (to develop H_2Se/SiH_4 and H_2S/SiH_4) is found to be higher in Se-doped -- than S-doped -- a-Si:H film due to a low defect density. From the measurement of intensity dependence of photoconductivity, it is found that the addition of Se and S changes the recombination mechanism from monomolecular, for low-doped films, to bimolecular …
Air Moisture Sensing Properties Of Zncr_2o_4--K_2cro_4 Composites, Neşe Kavasoğlu, Murat Bayhan
Air Moisture Sensing Properties Of Zncr_2o_4--K_2cro_4 Composites, Neşe Kavasoğlu, Murat Bayhan
Turkish Journal of Physics
Crystalline structure, surface morphology and the response to air moisture of ceramic system of composition ZnCr_2O_4 - K_rCrO_4 formed by solid state reaction at elevated temperatures were investigated. The fired ceramic body, which proved to be mainly constructed from about 1 \mu m sized ZnCr_2O_4 spinel grains, was found to be porous. The humidity sensing behaviour of the sensors reveals that the electrical conduction is protonic and is controlled through the thin layers of water adsorbed on the surface of the grains, with charge transfer to the electrodes. Only the material containing 20\% K_2CrO_4 in ZnCr_2O_4 exhibited an exponential behaviour …