Ayse Aroguz - Academia.edu (original) (raw)

Papers by Ayse Aroguz

Derived from chitin, chitosan is a unique biopolymer that exhibits, beside biocompatibility and b... more Derived from chitin, chitosan is a unique biopolymer that exhibits, beside biocompatibility and biodegradability, outstanding adsorption properties. The layer-by-layer (LBL) deposition technique is based on the alternated adsorption of materials bearing complementary charged or functional groups, in aqueous medium. As a consequence of the polycationic nature of chitosan, chitosan-based films can be used as sensors, drug delivery systems and in tissue engineering. The goal of work was to obtain innovative nano-composites beads based on hitosan, alginate and iron-oxide prepared using LBL deposition method, as magnetic adsorbents used for the separation of dyes from solutions and suspensions.Hitozan je jedinstveni biopolimer koji, pored biokompatibilnosti i biodegradabilnosti, pokazuje i odlična adsorpciona svojstva. Sloj po sloj tehnika (layer-by-layer, (LBL)) se zasniva na naizmeničnoj adsorpciji materijala sa komplementarno naelektrisanim ili funkcionalnim grupama, u vodenoj sredini...

Aim of this research was synthesis of chitosan/bentonite nanocomposite beads for colored wastewat... more Aim of this research was synthesis of chitosan/bentonite nanocomposite beads for colored wastewater treatment by adsorption. Influence of preparation procedure on the morphology, adsorption and thermal properties has been studied. It was proved that procedure method affects morphology, as well as enthalpy of absorbed water evaporation, which depends on the molarity of NaOH, and does not affect glass transition temperature. Chitosan adsorption capacity was improved by addition of modified bentonite, which is desirable in colored wastewater treatment.Cilj ovog istraživanja je bila sinteza hitozan/bentonit nanokompozitnih granula za prečišćavanje obojenih otpadnih voda metodom adsorpcije. Proučavan je uticaj postupka pripreme na morfologiju, kao i na adsorpciona i toplotna svojstva nanokompozitnih biopolimera. Dokazano je da način pripreme hibridnih granula utiče na morfologiju, kao i na entalpiju isparavanja adsorbovane vode čija vrednost zavisi od molarnosti NaOH, a ne utiče na tempe...

International Journal of Materials Engineering, 2020

In this study, the adsorption capacity of modified halloysite was systematically investigated wit... more In this study, the adsorption capacity of modified halloysite was systematically investigated with respect to temperature in a batch process. The halloysite mineral used in this work was alumina silicate mineral containing similarly structural layers. Halloysite mineral was obtained from Biga Peninsula, Western Anatolia. The characteristic properties of the modified halloysite were analyzed using X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR). The modification process of the halloysite was achieved using a Cetyltrimethylammonium bromide (CTAB) aqueous solution. Methyl orange was used as a model dye to find out the adsorptive percentage capacity of the modified halloysite. It was found that the adsorptive capacity of clay was increased by increasing the contact time and decreasing with temperature. The thermodynamic parameters as Gibbs Free Energy (ΔGo), Enthalpy (ΔHo), Entropy (ΔSo) changes were calculated and the results showed that adsorption is exother...

The Journal of medical research, 2017

Attribution-Noncommercial 3.0 Unported License http://creativecommons.org/licenses/by-nc/3.0/), p... more Attribution-Noncommercial 3.0 Unported License http://creativecommons.org/licenses/by-nc/3.0/), permitting all non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited. Investigation of the Presence of Different Animal Species within Processed Meat and Meat Products using PCR Procedures and Development of Risk Models based on Consumer Health By Harun Cerit & Ayse Z. Aroguz Istanbul University

Adsorption Science & Technology, 2018

Protection of Metals and Physical Chemistry of Surfaces, 2020

Pure and Applied Chemistry, 2019

The main purpose of academic studies is to be beneficial to humanity. Women in science are active... more The main purpose of academic studies is to be beneficial to humanity. Women in science are active contributors to academic research. Talented young women should be encouraged to pursue careers in academic science, in spite of long hours and low pay, because their contributions are valuable. This paper has been designed to explain the position of women in an academic organization and some situations faced by female academics as well as some of my academic experience.

International Journal of Polymeric Materials and Polymeric Biomaterials, 2015

ACS Symposium Series, 2010

Chemical Industry, 2014

Due to their biodegradable and nontoxic nature, biopolymer composites are often used as remarkabl... more Due to their biodegradable and nontoxic nature, biopolymer composites are often used as remarkable adsorbents in treatment of wastewater. In this study chitosan/bentonite composite beads were obtained by addition of clay into the polymer using solution process. Before the composite preparation, bentonite was modified with surfactant cetyltrimethyl ammonium bromide (CTAB). The morphology of beads was examined by scanning electron microscopy (SEM). Thermal properties of the composite beads were studied by simultaneous thermogravimetry coupled with differential scanning calorimetry (SDT) and differential scanning calorimetry (DSC). TG results showed that the complex decomposition mechanism of the composites depends on the preparation procedure. It was observed that the concentration of NaOH used for composites precipitation affects the final structure of beads. The influence of preparation procedure on the glass transition temperature Tg of chitosan/bentonite samples was not found (Tg ...

Journal of Applied Polymer Science, 2000

The miscibility of the binary and ternary blends of poly(2,6-dimethyl-1,4-phenylene oxide), bromi... more The miscibility of the binary and ternary blends of poly(2,6-dimethyl-1,4-phenylene oxide), brominated polystyrene, and polystyrene was investigated using a differential scanning calorimeter. The morphology of these blends was characterized by scanning electron microscopy. These studies revealed a close relation between the blend structure and its mechanical properties. The compatibilizing effect of poly(2,6-dimethyl-1,4-phenylene oxide) on the miscibility of the polystyrene/brominated polystyrene blends was examined. It was found that poly(2,6-dimethyl-1,4-phenylene oxide), which was miscible with polystyrene and partially miscible with brominated polystyrene, compatibilizes these two immiscible polymers if its contention exceeds 33 wt %. Upon the addition of poly(2,6-dimethyl-1,4-phenylene oxide) to the immiscible blends of polystyrene/brominated polystyrene, we observed a change in the morphology of the mixtures. An improvement in the mechanical properties was noticed.

International Journal of Biological Macromolecules, 2013

European Polymer Journal, 2007

Applied Biochemistry and Biotechnology, 2014

Supercritical fluids(SCFs) offer the possibility for obtaining and designing of new environmental... more Supercritical fluids(SCFs) offer the possibility for obtaining and designing of new environmentally friendly and sustainable products with special characteristics. Recently, SCFs have been applied for polymer processing,polymer extraction and purification, preparation of optical materials, supercritical blending of additives into polymers,as a foaming agent for microcellular materials, impregnation, fractionation, purification and formation of powdered polymers. This review is focused on some applications of supercritical fluids with special emphasis on their properties of supercritical fluids in water and carbon-dioxide green industrial chemical processes

Contemporary Materials, 2016

The use of synthetic chemical dyes in various industries, including plastics, paper manufacturing... more The use of synthetic chemical dyes in various industries, including plastics, paper manufacturing, cloth dyeing, printing and leather treatment, has increased considerably over the last years, resulting in the release of dye-containing effluents into the aquatic and soil ecosystems. There are many techniques to remove the waste after dying process (coagulation, chemical precipitation, reverse osmosis, extraction, filtration, biological treatment and adsorption). The releasing of dyes from many industrial plants is environmentally hazardous. The most important goal for the waste water purification is to find the low-cost adsorbents with high selectivity and long life. In our study, an effort has been made to prepare efficient composite materials for dyes removal from aqueous solution based on medium molecular weights deacetylated chitin i.e. poly(D-glucosamine) and a bio-degradable nontoxic anionic polysaccharide sodium alginate filled with magnetite nanoparticles. Alginate composite...

Contemporary Materials, 2017

In the case of irradiation of polymeric materials, the progress in oxidative degradation depends ... more In the case of irradiation of polymeric materials, the progress in oxidative degradation depends on absorbed dose, dose rate, exposure environment, energy of irradiation, chemistry of material, and previous state of ageing. It is known that the main effect of the interactions between gamma rays and rubber macromolecules is the formation of free radicals, whose further evolution can cause crosslinking with increase in the crosslinking density or chain scission. Chlorosulfonated polyethylene is specifically recommended for sheeting of cables in nuclear energetic plants. Elastomers based on this network precursor are resistant to wear and repeated deformation and have excellent irradiation resistance. The goal of the current work was to study the effects of γ-ray radiation for elastomers based on chlorosulfonated polyethylene in combination with nitrile rubber. The reinforcing filler was nano-silica. The irradiation was performed in the Co60 radiation sterilization unit. The level of a...

STED JOURNAL, 2019

Recently, controlled drug release systems have been garnering a lot of attention, due to more tar... more Recently, controlled drug release systems have been garnering a lot of attention, due to more targeted and effective approach for delivering drugs to a specific tissue. Because of a specific structure and natural abundance, clays are being added to those systems in order to increase its efficiency and minimize costs. In this study, controlled release kinetics of the drug active substance 5-Fluorouracil was studied, using halloysite clay/polymer drug carriers. For this purpose, the halloysite clay was initially modified with cetyltrimethyl ammonium bromide (CTAB). Drug carriers were prepared by adding modified halloysite clays in the mixtures of polyvinyl alcohol (PVA) and sodium alginate. Firstly, the swelling behaviour of the prepared substances was studied in buffer solutions at different pH. The drug release kinetics from the drug carriers, loaded with 5- Fluorouracil, was observed under a UV-spectrophotometer at 266 nm. Release profiles of the active substance were obtained by s...