Dayan, Serkan; Yavuz, Sevtap Çaglar; Yavuz, Emre

Nanomaterials have been used in catalytic degradation of organic pollutants also act as catalysts in for many years. Due to excellent catalytic performances of metal-based nanoparticles, these materials have been used extensively in various hybrid catalyst synthesis. The main subject of this study, heterogeneous catalysis is a low cost and multi-purpose process for many pollutants. Catalytic degradation of organic pollutants such as; 2-nitrophenol, quinolin yellow and rhodamine B was investigated by using Ni, Co, Pd nanoparticles modified SiO2 based nanomaterials. The co-doping effect on the prepared nanomaterials has been investigated with different characterization methods in terms of structural and morphological features: scanning electron microscopy, UV/vis absorption spectroscopy, energy-dispersive X-ray spectroscopy and foruier-transform infrared spectroscopy. The highest catalytic reduction efficiencies (97.6% and 97.5%) for 2-nitrophenol and rhodamine B was obtained by Pd-PEG-AP@SiO2 respectively. The synthesized Co-PEG-AP@SiO2 illustrated higher catalytic reduction efficiency for quinolin yellow (70.1%) at the end of 60s. The prepared M-PEG-AP@SiO2 nanomaterial (M: Pd,Co,Ni) can be able to utilized degradation of organic contaminants effectively.

Özdokur, K. Volkan

In this study, metal nanoparticles decorated metal oxide electrode was fabricated via electrochemicaltechnique. Firstly, molybdenum/copper oxide was electrochemically deposited on the bare glassy carbonelectrode surface. Then palladium nanoparticles were modified on this oxide functionalized surface byconsecutive potential cycles. Resulting composite electrode was characterized with scanning electronmicroscopy. The proposed composite electrode was employed for electrocatalytic oxygen reduction inalkaline media. As compared to bare electrode, the resulting composite surface has tremendous effect onoxygen reduction in terms of accelerated peak current values.

Dalkılıç, Feriştah; Çabuk, Umut Can; Dagdeviren, Orhan

Global positioning system and other outdoor positioning mechanisms are already subject to comprehensiveresearch and development for almost half a century. Conversely, indoor positioning services became a hottopic in the last decade. Since GPS (and. other outdoor solutions) do not work reliably in most indoorenvironments, researchers and developers are working on accurate positioning solutions, especially tailoredfor indoor places. However; due to walls, furniture, people and other obstacles, absolute location estimationis very hard and expensive to achieve in indoor places. In addition, accuracy needs depend on the scenarioand application. In this study, we have studied the feasibility of room-level location detection in home andoffice environments. We have focused on examining the quality of room-wise detection accuracy of thefingerprinting method that is applied along with standard Wi-Fi radio infrastructure. We have conductedexperiments in a multi-storey office building made of concrete and aerated concrete bricks with manyrooms, in which it is significantly hard to accurately estimate the correct place of a thing, using radio signals.To the best of our knowledge, our paper is the first study that investigates the room-level accuracy of Wi-Fi fingerprinting-based indoor localization systems. We have found out that, it is possible to feasibly achieveroom-level detection with good accuracy, via a pre-calculated room-specific received signal strengthindicator threshold value.

Dilmen, Zülküf; Taşyurdu, Yasemin

In this study, { } Fibonacci sequence was defined over an arbitrary ring and its some properties are investigated.The terms of this sequence are derivated by Tridiagonal determinant of the matrix. It was shown that this sequence is periodic and their period is obtained. It was shown that the sequence obtained by reducing modulo coefficient and exponent of each Fibonacci sequence in arbitrary rings is periodic. It was seen that order of cyclic group generated with matrix = [] is equal to the period of this sequence where , are arbitrary elements of the ring. Also, the period of this sequence is compared with Wall number of Fibonacci sequence and it was shown that this period always was an even number

Osma, Etem; Karakoyun, Güven; Elveren, Müjgan

The aim of this research is to investigate mineral element concentration, shell, branch, leaf and soil samples of the scots pine plant (Pinus sylvestris L. var. hamata Steven) in five different localities one of which is upper centrum of Erzincan. Collected plant and soil samples were exposed to a pretreatment in laboratory, and then their mineral element concentrations were analysed through ICPOES device. The plant and soil datas obtained were statistically evaluated and the differences between localities were detected. Besides, the results obtained were also compared with limited values of plants and soils. Consequently, it was observed in the statistical evaluation that there were significant differences between the mineral element content of the soils and plants collected from the city center and control region

Büyüktümtürk, Fuat; Sahin, Mustafa; Oğuz, Yüksel

In this study, the semi-direct and mixed types of lighting for the interior illumination have been compared in terms of technical aspects. The contribution of these lighting's type choices to the interior illumination has been address. Two different environments were selected and only the type of illumination was changed while all other physical condition of environments remains same. The semi-direct and mixed types of lighting were used for illumination and luminance level for each environment were measured 90cm above from the ground at many different points. These values were noted on a piece of paper as a matrix. Then, these values were drawn into a 3D graphic in MATLAB workspace to compare with each other. Thus, it has been observed that the chosen type of lighting system in design stage reduces the energy demand needed by the illumination elements. Consequently in this study, relationship of interior lighting type and its illumination level distribution were compared with numerical measurements. And it was concluded that the choice of lighting type contributes to illumination system positively in terms of both ergonomically and economical aspect