Showing papers by "Ahi Evran University published in 2007"
TL;DR: The authors' aliphatic sulfonamides have highest powerful antibacterial activity for Gram-negative bacteria than Gram-positive bacteria and antib bacterial activity decreases as the length of the carbon chain increases.
136 citations
TL;DR: In this paper, methyl parathion is used as an organophosphate insecticide that has been used in agriculture and domestic for several years, and after 4 weeks of exposure, glomerular atrophy and vascular dilatation were observed in the kidney tissues.
101 citations
TL;DR: In this paper, the frequency dependence of capacitance and conductance of SiO2/n-Si metal-insulator-semiconductor (MOS) structures with thermal growth oxide layer has been investigated taking into account the effect of the series resistance and interface states.
Abstract: Au/SiO2/n-Si metal–insulator-semiconductor (MOS) structures with thermal growth oxide layer have been fabricated. The frequency dependence of capacitance–voltage (C–V) and conductance–voltage (G/ω–V) characteristics of these structures have been investigated taking into account the effect of the series resistance and interface states. The C–V and G/ω–V measurements have been carried out in the frequency range of 1 kHz–1 MHz at room temperature. The frequency dispersion in capacitance and conductance can be interpreted in terms of the interface states density (Nss) and series resistance values (Rs). The interface states can follow the ac signal and yield an excess capacitance especially at low frequencies. The values of measured C and G/ω decrease in depletion region with increasing frequencies especially in low frequencies due to a continuous density distribution of interface states. The C–V plots exhibit anomalous peaks due to the Nss and Rs effect. It has been experimentally found that the peak positions in the C–V plot shift towards positive voltages and the peak value of the capacitance decreases with increasing frequency. The effect of series resistance on the capacitance is found appreciable at high frequencies due to the interface state capacitance decreasing with increasing frequency. In addition, the high-frequency capacitance (Cm) and conductance (Gm/ω) values measured under both reverse and forward bias were corrected for the effect of series resistance to obtain the real diode capacitance. Experimental results show that the locations of interface states between Si/SiO2 and series resistance have a significant effect on electrical characteristics of MOS structures.
36 citations
TL;DR: In this paper, two types of Schottky diodes with and without thermal growth oxide layer, were fabricated to investigate whether or not the thermal-growth oxide layer is effective on some electrical parameters such as ideality factor n, barrier height Φ B, series resistance R s and interface state density N ss.
Abstract: Two types of Schottky diodes with and without thermal-growth oxide layer, were fabricated to investigate whether or not the thermal-growth oxide layer is effective on some electrical parameters such as ideality factor n , barrier height Φ B , series resistance R s and interface state density N ss . The current–voltage ( I – V ) characteristics were measured for these two diodes at 150 K and room temperature (300 K). Electrical parameters of these two diodes were calculated and compared at two temperatures. At the temperatures of 150 and 300 K, Φ B , n , and R s for diode without oxide layer ranged from 0.50 to 0.81 eV, 4.12 to 1.54, and 481 to 156 Ω respectively. The Φ B , n , and R s for diode with thermal-growth oxide layer have ranged from 0.54 to 0.87 eV, 6.83 to 1.66, and 503 to 281 Ω, respectively. For two diodes, the temperature dependence energy density distribution profiles of interface state were obtained from forward bias I – V measurements by taking into account the bias dependence of effective barrier height Φ e and R s of the devices and the value of N ss in diode without oxide layer is almost one order of magnitude larger than the diode with oxide layer.
32 citations
TL;DR: A new species of Spermophilus is reported, distributed in the Taurus Mountains in southern Anatolia, Turkey, with Morphometrics, coat coloration, a brush-shaped tail, and a NFa value of 72 are diagnostic characters that distinguish S. torosensis sp.
Abstract: We report a new species of Spermophilus ( Rodentia: Sciuridae), here designated as S. torosensis sp. nov., distributed in the Taurus Mountains in southern Anatolia, Turkey. A total of 161 specimens of the genus Spermophilus from Turkey and Iran were analyzed for their morphological, morphometric, and karyological characteristics. Uni- and multi-variate statistical analyses of morphologic data for 95 adult specimens yielded 4 distinct groups. Taxonomic evaluations classified the specimens into 4 species Spermophilus citellus , S. xanthopymnus , S. fulvus and S. torosensis sp. nov. Morphometrics, coat coloration, a brush-shaped tail, and a NFa value of 72 are diagnostic characters that distinguish S. torosensis sp. nov. from the other species. In Turkey, S. torosensis sp. nov. was found in 6 locations. The karyotype of S. fulvus also is described for the first time as 2n= 36, NFa= 70 and NFa= 66; new karyotypic data is reported for S. xanthoprymnus from Iran and Turkey.
29 citations
TL;DR: Morphology, anatomy, hair properties and chromosome number and morphology of this species were analysed and chromosome number was counted as 2n = 14.
Abstract: Salvia blepharoclaena is an endemic species belonging to the family Lamiaceae. In this study, morphology, anatomy, hair properties and chromosome number and morphology of this species were analysed. Chromosome number of Salvia blepharoclaena was counted as 2n = 14.
25 citations
13 citations
TL;DR: In this article, the two-dimensional electron gas (2DEG) transport properties of two-step growth undoped Al0.25Ga0.75N/GaN heterostructures with semi-insulating buffer, grown by MOCVD, were investigated in a temperature range of 20-350 K.
Abstract: The two-dimensional electron gas (2DEG) transport properties of two-step growth undoped Al0.25Ga0.75N/GaN heterostructures with semi-insulating buffer, grown by MOCVD, were investigated in a temperature range of 20–350 K. Using the quantitative mobility spectrum analysis (QMSA) method, it was shown that significant parallel conduction does not occur in worked structures. In-plain growth axis strains are calculated using the total polarization-induced charge density taken as the sheet carrier density measured from the Hall effect. It was found that the calculated strain values are in good agreement with those reported. Influences of the two-step growth parameters such as growth ramp time, the annealing temperature of the GaN nucleation layer on the mobility, and density of the 2DEG are also discussed.
8 citations
TL;DR: In this article, resistivity and Hall effect measurements on n-type undoped Ga-rich InxGa1−xN (0.06≤x≤0.135) alloys were carried out as a function of temperature.
Abstract: Resistivity and Hall effect measurements on n-type undoped Ga-rich InxGa1−xN (0.06≤x≤0.135) alloys grown by metal-organic vapour phase epitaxy (MOVPE) technique are carried out as a function of temperature (15–350 K). Within the experimental error, the electron concentration in InxGa1−xN alloys is independent of temperature while the resistivity decreases as the temperature increases. Therefore, InxGa1−xN (0.06≤x≤0.135) alloys are considered in the metallic phase near the Mott transition. It has been shown that the temperature-dependent metallic conductivity can be well explained by the Mott model that takes into account electron–electron interactions and weak localization effects.
6 citations
02 Dec 2007
TL;DR: Mustafa Necati Sepetcioglu'nun yazdigi Karsilastirmali Turk Destanlari adli eseri tarih egitimi acisindan incelenmistir as discussed by the authors.
Abstract: Bu calismada, Mustafa Necati Sepetcioglu'nun yazdigi Karsilastirmali Turk Destanlari adli eseri tarih egitimi acisindan incelenmistir. Destan kavraminin anlami uzerinde kavramsal bir tartisma ile baslayan kitap, uc ana bolumden olusmustur. Birinci bolumde, kadim milletlerde yaradilis sorunsalina deginen destanlar, sira ile kisa ozetleri yapildiktan sonra karsilastirilmistir. Ikinci bolumde yapma destanlar cesitli acilardan karsilastirilmis, ucuncu bolumde ise Turk destanlarinin bir siniflamasi yapilmistir. Sepetcioglu, destanlarin degerini ortaya koyarken, milliligini ve destani yaratan milletin ozelliklerini temsil etmesini olcut almistir. Bunun yaninda gerekceli bir degerlendirmeye ozen gostermistir. Eserin, her uc bolumde de destanlari ele alis ve degerlendiris bakimindan tarih egitimine katki sagladigi soylenebilir.
3 citations
31 Aug 2007
TL;DR: The karyotypes of three vespertilionid bat species from Turkey were examined and the M. brandtii karyotype of was studied for the first time for Turkey.
Abstract: The karyotypes of three vespertilionid bat species from Turkey were examined. The karyotypes of these species were found as 2n=44, NF=54 and NFa=50 for Myotis myotis; 2n=42, NF=50, and NFa=46 for Myotis bechsteinii; 2n=44, NF=54, and NFa=50 for Myotis brand- tii. The M. brandtii karyotype of was studied for the first time for Turkey. Further details on the karyotype of M. bechsteinii, which had been described previously, are given.
TL;DR: In this paper, the structural and electronic properties of MgAuSn in the cubic AlLiSi structure have been studied using density functional theory within the local density approximation, and a linear response approach to density-functional theory is used to calculate the phonon spectrum and density of states for Mg AuSn.
Abstract: The structural and electronic properties of MgAuSn in the cubic AlLiSi structure have been studied, using density functional theory within the local density approximation. The calculated lattice constant for MgAuSn is found to be in good agreement with its experimental value. Our calculated electronic structure is also compared in detail with a recent tight-binding. A linear-response approach to density-functional theory is used to calculate the phonon spectrum and density of states for MgAuSn.
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TL;DR: Some fundamental solutions of radial type for a class of iterated elliptic singular equations including the iterated Euler equation are given in this paper, where the radial type is used to solve the Euler problem.
Abstract: Some fundamental solutions of radial type for a class of iterated elliptic singular equations including the iterated Euler equation are given.
01 May 2007
TL;DR: Some fundamental solutions of radial type for a class of iterated elliptic singular equations including the iterated Euler equation are given in this paper, where the radial type is used to solve the Euler problem.
Abstract: Some fundamental solutions of radial type for a class of iterated elliptic singular equations including the iterated Euler equation are given.