WoS İndeksli Yayınlar Koleksiyonu

Permanent URI for this collectionhttps://hdl.handle.net/20.500.14720/3

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0d, 1d, 2d, and 3d Soft and Hard Templates for Catalysis
(Elsevier Science Bv, 2017) Butun, Sultan; Demirci, Sahin; Yasar, Alper O.; Sagbas, Selin; Aktas, Nahit; Sahiner, Nurettin
[1,2,5]thiadiazolo[3,4-G]quinoxaline Acceptor-Based Donor-Acceptor Polymers: Effect of Strength and Size of Donors on the Band Gap
(Wiley, 2017) Gokce, Gurcan; Karabay, Baris; Cihaner, Atilla; Ozkut, Merve Icli
Electrochromic polymers based on [1,2,5]thiadiazolo[3,4-g]quinoxaline acceptor and thiophene, 3,4-ethylenedioxythiophene and 3,3-didecyl-3,4-proylenedioxythiophene donors, namely poly(6,7-diphenyl-4,9-di(thiophen-2-yl)-[1,2,5]thiadiazolo[3,4-g]quinoxaline) (P1), poly(4-(2,3-dihydrothieno[3,4-b][1,4]dioxin-5-yl)-9-(2,3-dihydrothieno[3,4-b][1,4]dioxin-7-yl)-6,7-diphenyl-[1,2,5]thiadiazolo[3,4-g]quinoxaline) (P2), and poly(4-(3,3-didecyl-3,4-dihydro-2H-thieno[3,4-b][1,4]dioxepin-6-yl)-9-(3,3-didecyl-3,4-dihydro-2H-thieno[3,4-b][1,4]dioxepin-8-yl)-6,7-diphenyl-[1,2,5]thiadiazolo[3,4-g]quinoxaline) (P3), respectively, were electrochemically and/or chemically synthesized and characterized. Electrochemical and optical properties of the polymers were then investigated. The results, which were obtained electrochemically and optically, indicate that the polymers bearing the same acceptor and different donor units have a band gap range of 0.59-1.24 eV depending on the strength and size of the donor units and band gap determination method. A significant finding in this study was the phenomenon that when the acceptor is physically huge, the general rule that a weak donor would have a high band gap whereas a strong donor would have low band gap can be broken due to the torsional angles/steric hindrances involved with physically large donor molecules. (c) 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017, 55, 3483-3493
1,3-Dipolar Cycloaddition Reactions of 1-Methyl Betaine With C70-A Theoretical Study
(Amer Scientific Publishers, 2009) Turker, Lemi; Gumus, Selcuk
In the present study, the molecular orbital properties of 1,3-dipolar cycloaddition products of 1-methyl-3-oxidopyridinium betaine with C-70 have been investigated theoretically at the level of PM3 (RHF) type semi empirical quantum chemical calculations and then single point DFT calculations were performed for the energies. The betaine acts as a 4 pi-component across its 2,6-positions and certain C=C bonds of C-70 act as 2 pi-component in the 1,3-dipolar cycloadditions considered presently. Various cycloadducts are structurally possible because C-70 structure possesses 8 different 2 pi-components, therefore 8 different pairs of reaction termini exist. The results indicate that, the cycloadducts (including regioisomers) formed with [6, 6]-type double bond are more stable and less endothermic than adducts formed with the [5, 6]-type with some exceptions. Some structural, spectral and physicochemical properties of these cycloadducts have also been studied.
2-[(2-Bromo-phen-yl)imino-meth-yl]-6-methyl-phenol
(int Union Crystallography, 2010) Karadag, Asli Tosyali; Atalay, Sehriman; Genc, Hasan
In the title compound, C14H12BrNO, is a Schiff base which adopts the phenol-imine tautomeric form in the solid state. The dihedral angle between the two aromatic rings is 34.26 (9)degrees and an intramolecular O-H center dot center dot center dot N hydrogen bond generates an S(6) ring.
2-[(E)-2-Hy-droxy-5-(trifluoro-meth-oxy)benzyl-idene-amino]-4-methyl-phenol
(int Union Crystallography, 2011) Karadag, Asli Tosyali; Atalay, Sehriman; Genc, Hasan
The title compound, C15H12F3NO3, is a Schiff base which adopts the cis-quinoid form in the solid state. The dihedral angle between the least-squares planes of the benzene rings being 3.6 (1)degrees. The F atoms of the -CF3 group are disordered over two sets of sites with refined occupancies of 0.61 (5) and 0.39 (5). An intramolecular N-H center dot center dot center dot O hydrogen bond occurs. The crystal structure is stabilized by intermolecular O-H center dot center dot center dot O hydrogen bonds.
The 2011 Van Earthquake S and Resilience in the Urban Population
(Istanbul Univ, Fac Letters, dept Geography, 2022) Choi, Jae hun; Alaeddiginoglu, Faruk
About a decade after the 2011 earthquakes, can people say that the city of Van has recovered now? This study purposes to answer this question by presenting a method for measuring the shock and process of recovering from an earthquake in terms of resilience and to provide objective results indicating whether or not Van has recovered from the shock of the 2011 earthquakes using this method. This study presents a method for measuring resilience in terms of population and local economic resilience. This study proposes the following five variables for measuring resilience in terms of population: decline year, drop (the degree of decline than expected), rebound (the velocity of recovery from decline), resilience index, and slope change (of the population regression equation). By synthesizing the resilience measurement results up to the end of 2019, the population growth rate of the whole city has yet to return to pre-earthquake levels. When measuring the resilience indicators at the neighborhood level, the neighborhoods that Housing Development Administration of Turkiye (TOKI) had built and the neighborhoods around the city center show high resilience. The resilience indicators for neighborhoods near TOKI were low. The conclusion is that appropriate measures have not been taken from the perspective of the entire city of Van to overcome the effects of the 2011 earthquakes.
238u and 222rn Activity Concentrations and Total Radioactivity Levels in Lake Waters
(Springer, 2013) Zorer, O. Selcuk; Sahan, T.; Ceylan, H.; Dogru, M.; Sahin, S.
The concentrations and distributions of natural radioactivity, uranium and radon in lake waters from around Van, Turkey were investigated with an aim of evaluating the environmental radioactivity. Fourteen lake waters were collected from different six lakes around Van (Turkey) to determine U-238, Rn-222 and total alpha and total beta distributions in 2009. The total alpha and total beta activities were counted by using alpha/beta counter of the multi-detector low background system (PIC-MPC-9604) and the U-238 concentrations were determined by inductively coupled plasma-mass spectrometry (Thermo Scientific Element 2) and radon concentrations were measured with the solid state nuclear track detector technique. The activity concentrations ranging from ND to 0.039 Bq L-1 and from 0.026 to 3.728 Bq L-1 for total alpha and beta, respectively, and uranium concentrations ranging from 0.083 to 3.078 mu g L-1, and radon concentrations varying between 47.80 and 354.86 Bq m(-3) were observed in the lake waters.
3,5-Dibenzoyl
(int Union Crystallography, 2009) Sahin, Zarife Sibel; Isik, Samil; Sener, Ahmet; Tan, Meltem
In the crystal structure of the title compound, C26H27NO3, a one-dimensional network of C-H center dot center dot center dot O hydrogen bonds and pi-ring interactions is responsible for crystal stabilization. Intermolecular hydrogen bonds and C-H center dot center dot center dot pi interactions produce R-2(2)(10), R-4(4)(27) and R-4(4)(29) rings.
A 3-Db 90 Degrees Microstrip Hybrid Directional Coupler at 2.27 Ghz
(Elsevier Gmbh, 2023) Imeci, Mehmet Yusuf; Tutuncu, Bilal; Imecl, Sehabeddin Taha
A 90 degrees hybrid-coupler in the 2.27 GHz range, offering high performance despite its size of 115.64 mm2 (18.36 & lambda;g), is introduced. The main factor that distinguishes this proposed design, positively, is that the device demonstrates high fabrication tolerances due to its simplicity, and uncomplicated length dimensions. At the center of the structure are 9 metal squares, all of equal size and equidistant. It has been observed that the S-parameters remain relatively the same after increasing or decreasing the side lengths, substrate parameters, and the vertical separation dimensions. Based on these results, it has been shown that the design will provide a successful fabrication tolerance. According to the simulation results, the S-parameters are as follows: S11 = -24.01, S12 = -3.063, S13 = -3.063, and S14 = -23.47 (all in dB). The phase deviation is only 0.8 degrees. After the simulation studies, a prototype of the coupler was fabricated, and laboratory measurements were made. The simulated and measured results, have desirable agreement. Finally, a few similar studies presented in the literature are discussed with a comparative table, in terms of overall size, isolation, phase deviation, and structure complexity. Thus, the advantages of this presented structure, compared to these studies, have been revealed.
500,000 Years of Environmental History in Eastern Anatolia: the Paleovan Drilling Project
(Copernicus Gesellschaft Mbh, 2012) Litt, Thomas; Anselmetti, Flavio; Baumgarten, Henrike; Beer, Juerg; Cagatay, Namik; Cukur, Deniz; Wonik, Thomas
International Continental Scientific Drilling Program (ICDP) drilled a complete succession of the lacustrine sediment sequence deposited during the last similar to 500,000 years in Lake Van, Eastern Anatolia (Turkey). Based on a detailed seismic site survey, two sites at a water depth of up to 360 m were drilled in summer 2010, and cores were retrieved from sub-lake-floor depths of 140 m (Northern Basin) and 220 m (Ahlat Ridge). To obtain a complete sedimentary section, the two sites were multiple-cored in order to investigate the paleoclimate history of a sensitive semi-arid region between the Black, Caspian, and Mediterranean seas. Further scientific goals of the PALEOVAN project are the reconstruction of earthquake activity, as well as the temporal, spatial, and compositional evolution of volcanism as reflected in the deposition of tephra layers. The sediments host organic matter from different sources and hence composition, which will be unravelled using biomarkers. Pathways for migration of continental and mantle-derived noble gases will be analyzed in pore waters. Preliminary 40Ar/39Ar single crystal dating of tephra layers and pollen analyses suggest that the Ahlat Ridge record encompasses more than half a million years of paleoclimate and volcanic/geodynamic history, providing the longest continental record in the entire Near East to date.
8-Ohdg Levels in Patients With Allergic Rhiniti
(Yerkure Tanitim & Yayincilik Hizmetleri A S, 2011) Onbasi, Kevser; Noyan, Tevfik; Cebi, Aysegl; Kiroglu, Faruk
Objective: Respiratory allergies like allergic rhinitis and allergic asthma are more frequently observed worldwide. Chronic inflammation in the respiratory tract is observed in these diseases. Oxidative stress contributes to this inflammation in the respiratory airways. 8-OHdG is a marker of oxidative stress. The aim of our study was to investigate the 8-OHdG levels in patients with respiratory allergy. Material and Methods: 23 patients with allergy consisting of 11 men and 12 women and 23 healthy controls were enrolled to the study. Results: 8-OHdG levels were found to be higher in allergic patients in comparison to healthy controls but it was not statistically significant. Conclusion: The reason for not significantly high levels of 8-OHdG levels as a marker of oxidative stress in respiratory allergy may attribute to the factor that the inflammation in respiratory allergy is less intensive in comparison to the inflammation in atopic dermatitis.
Aas Determination of Some Trace Heavy Metals in Lake Van Water After Preconcentration by Complexation With Surface Functional Groups on Activated Carbon
(Parlar Scientific Publications (p S P), 2005) Kiliçel, F; Gökalp, F
The adsorption of some trace heavy metals on a granulated, pure and activated carbon (Riedel-de Haen, 18002) was characterized assuming that it takes place by formation of complexes with functional groups, present in the activated carbon. The concentrations were determined for each element in aqueous suspension at constant acidity. An atomic absorption spectrometric method for the determination of the trace heavy metals (Zn, Pb, Cd, Cr, Ni, Cu, Co, Bi, Mn) in Lake Van water and that of the rivers flowing into the lake has been developed after adsorption of their diethyldithiocarbamate (DEDTC) complexes on activated carbon. Complexes were adsorbed on the adsorbent at pH 3.2 +/- 0.1. Trace heavy metal ions were elueted with 20 ml of 1 M HNO3 and determined by flame atomic absorption spectrometry (FAAS). Under optimum conditions, the trace heavy metal ions in aqueous samples were concentrated about 50-fold by column treatment and recovery rates of the investigated metals were in the range 79-106%.
Ab Initio Calculation of Physical Properties of Sodium Chloride
(Amer Scientific Publishers, 2013) Dogan, Emel Kilit; Secuk, Nurullah; Erdinc, Bahattin; Soyalp, Fethi; Akkus, Harun
We have calculated the structural, electronic, optical, dynamical, and thermodynamical properties of sodium chloride crystal using the density functional theory within the generalized gradient approximation. The calculated results for each physical property are presented and compared with available experimental data and previous theoretical data. There are controversial reports in the literature on the electronic band structure of sodium chloride. We especially present data and comments about this controversial subject.
Ab Initio Study of Li2cata2o7 Compound: Electronic and Optical Properties for Three Phases
(Tubitak Scientific & Technological Research Council Turkey, 2019) Aycibin, Murat
The Li2CaTa2O7 compound belongs to the Ruddlesden-Popper family of layered perovskites. First principle approximation was used to investigate the electronic band structure and optical properties of the compound for three phases. Independent of the studied compound's structural type, Li2CaTa2O7 has semiconductor behavior and direct transition. In addition, the forbidden energy band gap of the compound decreases with rising temperature, as expected. Furthermore, the 3d orbital of Ca contributes to the conduction band due to the crystal field effect. Moreover, the optical response of the chosen axes of the compound to incoming electromagnetic rays varies with phase transition.
Ab-Initio Calculations of Physical Properties of Alkali Chloride Xcl (X = K, Rb and Li) Under Pressure
(Elsevier, 2015) Erdinc, Bahattin; Secuk, Mehmet Nurullah; Aycibin, Murat; Gulebagan, Sinem Erden; Dogan, Emel Kilit; Akkus, Harun
Structural properties, electronic band structure, real and imaginary parts of complex dielectric function of alkali chloride XCl (K, Rb and Li) compounds were investigated under various pressures using first principles calculations. Moreover, Gibbs free energies were also calculated at those pressures. Calculated results of the Gibbs free energy show that LiCl does not show any structural phase transition. However, structural phase transitions of KCl and RbCl occur from NaCl (B1) to CsCl (B2) at 4.5 and 1.7 GPa pressures, respectively. The electronic band gaps under pressure were also calculated. The calculated physical properties of these compounds are compared with the previous theoretical and experimental results and a good agreement was observed. (c) 2015 The Authors. Published by Elsevier B. V. This is an open access article under the CC BY-NC-ND license.
Absorption Ratio of Treatment Couch and Effect on Surface and Build-Up Region Doses
(Elsevier Science Bv, 2018) Tugrul, Taylan
Aim: In this study, at different fields, energies and gantry angles, treatment couch and rails dose absorption ratio and treatment couch effect on surface and build-up region doses were examined. Background: It is assumed that radiation attenuation is minimal because the carbon fiber couches have low density and it is not generally accounted for during treatment planning. Consequently, it leads to a major dosimetric mistake. Materials and methods: Solid water phantom was used for relative dose measurement. The measurements were done using a Farmer ion chamber with 0.6 cc volume and a parallel plane ion chamber starting from surface with 1 mm depth intervals at 10 x 10 cm(2) field, SSD 100 cm. Measurements were taken for situations where the beams intersect the couch and couch rails. Results: Dose absorption ratio of carbon fiber couch obtained at gantry angle of 180 was 1.52%, 0.69%, 0.33% and 0.25% at different field sizes for 6 MV. For 15 MV, this ratio was 0.95%, 0.27%, 0.20% and 0.05%. The absorption ratio is between 3.4% and 1.22% when the beams intersect with couch rails. The couch effect increased surface dose from 14% to 70% for 6 MV and from 11.34% to 53.03% for 15 MV. Conclusions: The results showed that the carbon fiber couch increased surface dose during posterior irradiation. Therefore, the skin -sparing effect of the high energy beams was decreased. If the effect of couch is not considered, it may cause significant differences at dose which reaches the patient and may cause tissue problems such as erythema. (C) 2017 Greater Poland Cancer Centre. Published by Elsevier Sp. z o.o. All rights reserved.
Abstrackt Pictorial Images in the Teaching of Shaman
(Anadolu Univ, 2011) Kiran, Hasan
Images could be regarded as internalized sensations. They stand for the state where outputs of the earth react in human sensitivity. One can visualise the image of an object in its absence and create its visual illustration. Artist can express shamanistic messages through myths in the form of symbols. Since shaman's world conserve its natural and unique mystery ever, artists tend to employ it in their works. Particularly shaman's unique, creative and natural dance, his inner trance state, ecstasic instrument playing, rich imagination, experiences and esoteric sayings arouse artists's interest. All these aspects could be utilized as essential elements in the world of imagery.
Academic and Non-Academic Staff's Psychological Contract in Turkey
(Wiley, 2008) Aydin, Inayet; Yilmaz, Kursad; Memduhoglu, Hasan Basri; Oguz, Ebru; Gungor, Sabri
Studies of psychological contract as part of organisation-individual agreements have become important in recent years. This study determines views, about the psychological contract, of academic and non-academic staff and managers in faculties of education in Turkey. A total of 442 employees at 11 state universities in Turkey were included in the research. 'Psychological Contract Inventory' and 'Psychological Contract Measures', designed by Rousseau were utilised during the development process of the data-gathering tool. After the adaptation work, the scale consisted of 68 items under three sections and seven subscales. The results showed that academic staff and executives considered that their university carried out its obligations towards the staff at a 'moderate' level, whereas the non-academic staff considered it 'insufficient'. The academic and the non-academic staff considered that the employees carried out their tasks at a 'maximum' level, whereas the executives considered it 'moderate'.
Accessibility Analysis of Urban Green Space: the Case of Erbil City
(Konya Technical Univ, Fac Architecture & design, 2023) Kemec, Serkan; Abdalkarim, Salar Hassan
Urban green areas are open spaces in urban areas that are mainly covered by vegetation. They can be public or private urban green spaces that include parks, community gardens, forests, and nature reserves. Parks are an important component of urban quality of life if they are well designed and accessible. Accessible parks contribute to physical activity among urban residents. Therefore, the objective of the study was to identify the most significant main accessibility factors that discourage the use of public urban green areas, and examine the extent to which they influence the use of green areas in residential areas of the city of Erbil. This study was conducted in 2017 and 2020 to measure the accessibility of green spaces using network analysis with GIS for Erbil city. The present study represents the first known investigation regarding the accessibility of public green spaces within the city of Erbil. The results show that for community parks, 68% of the population has access with a travel time of 5 minutes, 99% of the population has access with a travel time of 10 minutes, and 100% of the population has access with a travel time of 15 minutes. For district parks, 70% of the population had access with 5 minute drive time. With 10-minute drive time, 96% of the population had access and 100% of the population had access with 15-minute drive time. For neighborhood parks, the results show that 43% of the population had access with 5-minute walk and, 71% of the population had access with 10-minute walk. At 15-minute walk time, 80% of Erbil residents had access to neighborhood parks. Mini parks were accessed by 22% of the population with a 5 minute walk and they were accessed by 52% of the population with a 10 minute walk. With a 15 minute walk, mini parks were accessible to 70% of the population.
Accumulation and Distribution of Iron, Zinc and Manganese Ions in Pumpkin (Cucurbita Spp.) and Gourd (Lagenaria Siceraria) Accessions Subjected To Drought Stress
(Cukurova Univ, Fac Agriculture, 2012) Yasar, F.; Uzal, O.; Kose, S.
The aim of this study was to observe the distribution of ions in different organs of pumpkin and gourd accessions commonly grown in Turkey, in order to better assess drought stress-tolerance mechanisms. Seedlings of 38 accessions of pumpkin (Cucurbita spp.) and gourd (Lagenaria siceraria) were cultured in cups containing Hoagland's nutrient solution in a controlled climate chamber. To simulate drought stress, 15% polyethylene glycol (PEG6000), equivalent to -0.60 Mpa of osmotic potential, was added to the nutrient solution. Following its application, the accumulation and distribution of iron (Fe), zinc (Zn), and manganese (Mn) ions in the roots, shoots, and leaves of the seedlings were observed using atomic absorption spectrometry (AAS) flame photometry. Ion accumulation increased in plants subjected to drought stress in comparison to the control plants. The greatest increase occurred in the leaves.

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