416 research outputs found
Structure and thermal decomposition of mu-1,1-azido bridged dinuclear Fe(III) complexes
No full textErcan, ismail/0000-0001-6490-3792; Ercan, filiz/0000-0002-3533-0726;WOS: 000249792800009Fe(III) complexes were prepared by the reaction of two different ONNO type Schiff bases N,N'-bis (salicylidene)-1,3-propanediamine (LH2) and N,N'-bis (salicylidene)-2,2'-dimethyl-1,3-propane diamine (LDMH2) in N-3(-) containing medium. The X-ray diffraction studies revealed that the complexes are of dinuclear type connected with mu-1,1-azido bridges. It was observed from the thermogravimetric analyses of the complexes that the azide group decomposed around 200 degrees C with exothermic reaction. This exothermic decomposition did not affect the rest of the molecule. Following the decomposition of the azide group the remainder of the molecule decomposed with carbonization process. It was seen that the molecule decomposed into Fe2O3 above 650 degrees C in oxygen containing medium. [FeLDMN3](2) complex was found to have N4O2 distorted octahedral sphere with Fe...Fe distance of 3.414 angstrom
The Role of Public Relations on the Rise of Financial Performance in Business and Public Relations Perception
No full textBu çalışmanın amacı; işletmelerin halkla ilişkiler algısını ve halkla ilişkilere verdikleri önemi ortaya koymak ve halkla ilişkilerle ilgili faaliyetlerin finansal performanslarına etkisini ölçmektir. Bunun için, 115 işletmenin yöneticileri ile yapılan anket’ten elde edilen veriler, yapısal eşitlik modeli (YEM) ve ANOVA testi kullanılarak analiz edilmiştir.
Sonuçlara göre; yöneticiler halkla ilişkiler terimini genellikle müşteri ilişkileri yerine kullanmaktadır. Halkla ilişkilere verilen önemle işletmenin bilinirliği arasında pozitif ilişki bulunmaktadır. Çalışmanın bir diğer sonucu halkla ilişkilerin işletmelerin finansal performansını olumlu olarak etkilediğini öne sürmektedir.
Son olarak, bu çalışma politika yapıcılara ve işletme yöneticilerine paydaşlarıyla daha etkin bir iletişim kurabilmek için halkla ilişkilerin önemiyle ilgili önerilerde bulunmaktadır
Time-dependent changes in distribution of basic fibroblast growth factor immunoreactive cells in hippocampus after kainic acid injection in rat pups
No full textFive-day-old Wistar albino rats were injected with kainic acid (KA) or saline i.p. to investigate time-dependent alterations in morphology and number of basic fibroblast growth factor (bFGF) immunoreactive (-ir) astrocytes and neurons in hippocampus at 15, 30, and 90 days after the injections. Sections were stained with cresyl violet for morphological evaluation and bFGF immunohistochemistry was used for quantitative evaluation of bFGF-ir cell density. Fifteen days after KA injection, there was gliosis but no neuronal loss although disorganization in CA1, CA3, CA4 pyramidal layers and neuronal loss were evident 30 and 90 days after the injection. KA injected rats demonstrated significantly increased number of bFGF-ir astrocytes throughout the hippocampus and pyramidal neurons in CA2 after 15 days and decreased number of bFGF-ir cells after 30 and 90 days. The decrease in the number of bFGF-ir astroglia and neurons in long term after KA injection may indicate a decrease in the production of bFGF and/or number of bFGF-ir cells suggesting that protective effects of bFGF may be altered during epileptogenesis in hippocampus. (c) 2007 ISDN. Published by Elsevier Ltd. All rights reserved
Organic Waste as a Soundproofing Material: an Experimental Study
No full textKöse, Ercan/0000-0001-9814-6339; BAL KOCYIGIT, Filiz/0000-0003-4191-0724Using sound insulation materials that do not impair indoor air quality and do not emit carbon.Increasing the sound insulation capacity with combinations of different natural materials.To enable to increase the intensity of use thanks to its economical production. Objective The aim of the study is to develop new acoustic materials and panels that high sound transmission loss (STL), low carbon emissions, high sensitivity to human health, and also do not harm the indoor air quality. These materials are currently grown in Turkey and can be easily adopted in the industry. It has been comparatively analyzed that the developed materials can be alternatives to the synthetic materials on the market.Methods In the experiment box similar to Alpha Cabin, which was designed and developed before, the STL values were obtained by conducting experiments in the frequency range 500-8000 Hz. with many natural and synthetic materials. In the study, low carbon emission natural materials with a STL of more than 30 dB were selected.Simulation The experimentally measured samples were simulated in the acoustic module of the ANSYS program and compared with the results.Conclusion The main purpose of choosing cones and walnut shells grown in our country is to contribute to the amount of oxygen in the atmosphere and green areas by increasing the cultivation of pine and walnut trees. In the tests of the samples, it was determined that the highest STL was 63.27 dB in the concave and egg-shaped sample, and 62.41 dB in the concave walnut shell and egg form. It is envisaged that the materials we obtained can be used in the sound insulation of machines and devices that produce 85 dB and above sound harmful to human health according to ILO and WHO standards.Tarsus UniversityNo Statement Availabl
The Role of Physical, Human and Social Capital in Regional Financial Development Differences: An Analysis of Turkish Provinces
No full textThe Role of Physical, Human and Social Capital in Regional Financial Development Differences: An Analysis of Turkish Provinces Ercan Dulgeroglu , Sibel Bali Eryigit , Kadir Y. Eryigit and Filiz Gaygusuz Abstract With the undeniable importance of the financial markets in the economy, the factors stimulating financial development have started to be researched, particularly in recent times in a more intensive way. Starting from this point, the driving force of this study is both to contribute to international literature in this field and to fill a gap in the literature related to Turkey. The main purpose of this study is to explain the causes of regional financial development differences on the basis of capital accumulation. In order to answer the question ‘What is the effect and degree of importance of physical, human and social capital on the differences in regional financial development?’, in this study some indexes for financial development and each type of capital accumulation will be calculated using kernel principle components analysis and depending on the annual data of 81 provinces covering the period 2005 – 2009. As an index, the capital measurements can be seen in a comprehensive form allowing for more accurate measurement and evaluation of both the capital accumulation and financial development. By using the calculated indexes, then, financial development differences are evaluated with spatial panel data methods developed by Elhorst (2003). In this context, to our knowledge, this study is the first to take into account the effects of each type of capital on financial development in a model simultaneously. Keywords: Financial development, physical capital, human capital, social capital, spatial panel data analysis,
Heat Treatment Effects on the Structural and Electrical Properties of Thermally Deposited Agin<sub>5</Sub>s<sub>8< Thin Films
No full textErcan, filiz/0000-0002-3533-0726; Qasrawi, Atef Fayez/0000-0001-8193-6975; Kayed, Tarek/0000-0003-3482-4166The heat treatment effects on structural and electrical properties of thermally deposited AgIn5S8 thin films have been investigated. By increasing the annealing temperature of the sample from 450 to 500 K, we observed a change in the crystallization direction from (420) to (311). Further annealing of the AgIn5S8 films at 550, 600 and 650 K resulted in larger grain size in the (311) preferred direction. The room temperature electrical resistivity, Hall coefficient and Hall mobility were significantly influenced by higher annealing temperatures. Three impurity levels at 230, 150, and 78 meV were detected for samples annealed at 350 K. The electrical resistivity decreased by four orders of magnitude when the sample annealing temperature was raised from 350 to 450 K. The temperature dependent electrical resistivity and carrier concentration of the thin film samples were studied in the temperature ranges of 25-300 K and 140-300 K, respectively. A degenerate-nondegenerate semiconductor transition at approximately 180 was observed for samples annealed at 450 and 500 K. Similar type of transition was observed at 240 K for samples annealed at 600 and 650 K. (C) 2011 Elsevier Ltd. All rights reserved
Simulation based optimization for world line card production system
No full textApak, Sinan (Arel Author), Ercan, Sami (Arel Author)Simulation based decision support system is one of the most commonly used tools to examine complex production systems. The simulation approach provides process modules which can be adjusted with certain parameters by using data relatively easily obtainable in production process. World Line Card production system simulation is developed to evaluate the optimality of existing production line via using discrete event simulation model with variety of alternative proposals. The current production system is analysed by a simulation model emphasizing the bottlenecks and the poorly utilized production line. Our analysis identified some improvements and efficient solutions for the existing system
Modal properties of parallel plate waveguide partially loaded with double negative materials
No full textPekmezci, Ayşegül (Dogus Author) -- Topuz, Ercan (Dogus Author)Properties of eigen-solutions in parallel plate waveguides partially loaded with Lorentz type Double Negative Materials (DNG), modelled by lossless/lossy, identical/non-identical electric, magnetic parameters are presented. Modal cut-off phenomena associated with surface waves, transitions between evanescent/propagating, forward/backward waves and their dependence on frequency, filling factor and dispersive material parameters are investigated. Novel conditions are given for the existence of surface waves and for the emergence of complex eigenvalues in the absence of losses, and supported with numerical results of exact frequency domain analysis
Finite difference time domain formulation for epsilon-negative medium using wave equation
No full textPekmezci, Ayşegül (Dogus Author) -- Topuz, Ercan (Dogus Author)A novel approach utilizing one-dimensional (1D) wave equation based finite difference time domain (FDTD) formulations for Lorentz-type Epsilon-Negative (ENG) medium is developed. To demonstrate the validity and accuracy of the formulation, reflection of a plane wave normally incident at free spaceENG interface is compared with the analytical solution. Moreover, propagation characteristics of Lorentz-type ENG medium is investigated using the FDTD formulations both for wave equation and Maxwell's curl equations in 1D case. Comparisons of memory and computational time requirements of both formulations are given
Effect of aging on the distribution of basic fibroblast growth factor immunoreactive cells in the rat hippocampus
No full textHippocampal formation is extremely sensitive to the aging process and appears to be one of the first regions to show structural and physiological changes with advancing age. Basic fibroblast growth factor (bFGF) plays an important role in the stimulation of mitogenesis in glial cells, the support of neuronal survival and the promotion of neurite outgrowth in vitro. In the present study, the effect of aging on the distribution of bFGF immunoreactive (bFGF-ir) cells was investigated. The protein product of bFGF was visualized immunohistochemically in the dorsal hippocampus of Wistar albino rats. bFGF-ir astrocytes in different subfields of hippocampus and neurons in CA2 field were quantified to determine whether changes in immunoreactivity were correlated with advancing age. Aging was accompanied by a decrease in bFGF-ir cell density in subfields of hippocampus. We concluded that aging was associated with a reduction in bFGF-ir cell density that may reflect a decreased expression of bFGF in the rat hippocampus. (C) 2004 Elsevier Inc. All rights reserved
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