Master Degree / Yüksek Lisans Tezleri
Permanent URI for this collectionhttps://hdl.handle.net/11147/3008
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Master Thesis Production and Characterization of Water Soluble Cdsete Based Core/Shell Nanocrystals and Their Applications in Bioimaging(İzmir Institute of Technology, 2009) Özdemir, Seda; Özçelik, SerdarIn recent years, nanotechnology has become one of the most intensively studied fields. At the nanometer scale, materials have unique electrical, optical, magnetic and chemical properties. They can be used for a wide variety of applications such as electrooptical devices, tagging and medical applications. The goal of this study was to produce water-dispersible alloyed CdSexTe1-x semiconductor nanocrystals, which are suitable to interact with biomolecules. CdSexTe1-x nanocrystals were synthesized by a single step aqueous synthesis method. Monodisperse, CdSexTe1-x nanocrystals with zinc blende structure were obtained in water. Synthesized nanocrystals emit in the range from 528 nm to 620 nm. CdSexTe1-x nanocrystals have 17% photoluminescence quantum yield, after the CdS shell coating the photoluminescence quantum yield increased up to 22%. MTT test and Trypan Blue tests were used to evaluate the toxicity of CdSexTe1-x nanocrystals. MTT measurements reveal that the MCF7 cancer cells are not affected by the nanocrystals at any dosage and exposure condition, but lethal effects are determined at the concentration of 1.0ug/ml for the PC3 cells. The BEAS 2B cells are very sensitive to the nanocrystals and do not proliferate at concentration of 0.5ug/ml. Confocal microscopy studies show that the nanocrystals has ability to penetrate to the cytoplasm of cells.Master Thesis The Evolution and Change of Building Facades: a Research for Developing Alternative Composite Surface Materials(İzmir Institute of Technology, 2007) Çıkış, Dilaver Turgut; Günaydin, Hüsnü MuratCladding of buildings is an important and commonly applied activity area of building sector. As it is known major purpose of cladding is to separate the indoor environment from the outdoors in such a way that indoor environment conditions can be maintained at level suitable for the buildings intended use. Therefore from the functional point of view it can be defined as, the part of the building that is non load bearing exterior wall that must defend the interior spaces against invasion by water, wind, sun, light, heat and cold, and all the other forces of nature. Besides this it must also fulfill the aesthetic, economic and security consideration. The design of the building façade has become much more complicated with development of new methods of construction, the requirements for a highly controlled interior environments, stress on energy efficiency, advent of materials and new production methods. But it seems that available technologies on ordinary building sector relay on the analog production methods. Analog production process depends on technical drawings and the interpretation of drawings. The human interpretation is the basics of the systems. On the other hand, new design tools that introduced by computer aided design programs proposes new conceptions of space that beyond the limits of Cartesian understanding of form and construction. It is known that computer aided design and production methods are applied pervasively in numerous different sectors. Articulation of computer aided design and manufacturing processes with digitally driven assemblage methods is an important task that is expected to be solved by the building sector. Building envelope systems as being one of the most important building component from the points of both identity and utility of buildings, is has to be reconsidered as a part of the adaptation of whole construction sector. It is also a measure of responsibility on the part of architects. Besides material design, production processes, and connection details of the components with the other parts of the building are the other important dimensions of the envelope systems.Master Thesis Hiv-1 Regulatory Gene Dependent Expression of a Toxic Gene(İzmir Institute of Technology, 2006) Yeğin, Zeynep; Arslanoğlu, AlperFrom the first day it was discovered, HIV remains as one the major health threats of 21st century and the methods tried up to now focused on the short-term solutions which were efficient at blocking HIV replication, but also resulted with drugresistant strains, instead of methods which would completely eliminate HIV-infected cells from potential reservoirs. In this study, the design of a special DNA vector encoding a toxic protein to be expressed only in cells infected with HIV, thereby not damaging to healthy cells and the test of the efficacy of this vector in the cell culture conditions without using HIV infection was aimed. The toxic gene (suicide gene) presumed to create the desired effect was placed under the transcriptional control of HIV promoter LTR and so that the expression of the toxic gene was made dependent upon the tat regulator gene of HIV. In order to prevent leaky gene expression stemming from the basal gene expression from LTR even if it was not induced by Tat, and thereby having potential to damage healthy cells, the prerequisite cis-acting DNA sequences were cloned downstream of the toxic gene. So that, the transcripts produced could retain in the nucleus and would require the function of a second regulator protein 'Rev' which is a molecular chaperone for being transmitted into the cytoplasm. If the efficiency of this model prooved, a full-protective suicide vector will have been designed and this vector may be suggested to be tested in gene therapy trials of HIV infection in the future.Master Thesis Comparative Adsorption Studies of Heavy Metal Ions on Chitin and Chitosan Biopolymers(İzmir Institute of Technology, 2007) Keleşoğlu, Serkan; Polat, Hürriyet; Polat, HürriyetIn this study comparative adsorption studies of heavy metal ions (Cu2+, Pb2+,Cd2+, Ni2+) on chitin and chitosan biopolymers were performed to investigate the uptake performances. For this purpose chitosan was prepared from chitin in controlled experimental conditions and then these biopolymers were characterized with Elemental Analysis, Viscosity, FT-IR, Potentiometric Titration, XRD, SEM, Zeta Potential,Particle Size Distribution and TGA/DTA measurements. Batch adsorption experiments were performed at eight different initial heavy metal ion concentrations (10, 25, 50, 100, 250, 500, 750, 1000 m/L), two different temperatures (298.15 K and 328.15 K), time period ranging from 5 minutes to 1 day and pH of solutions ranging from 1 to 7. The results indicated that the uptake performence of chitin and chitosan biopolymer significantly changed with pH, adsorbent dosage,concentration and temperature. In general, chitosan biopolymer demonstrated greater fixation abbility for heavy metal ions than chitin. However the fixation trend of heavy metal ions on chitin and chitosan biopolymers was the same (Cu2+ > Pb2+ > Cd2+ > Ni2+). Moreover Irwing-Williams Series support the dominancy of the binding mechanism for Cu2+, Cd2+ and Ni2+ ions on both biopolymers. Adsorption of heavy metal ions on both chitin and chitosan biopolymers followed pseudo second order kinetics with the rate constant indicating faster adsorption on chitin for Cu2+ and Pb2+ ions and faster adsorption on chitosan for Cd2+ and Ni2+ ions.Both of the Freundlich and Langmuir adsorption isotherms seem to adequately represent the adsorption data obtained in this study. The positive value of enthalpy change (Ho) and negative value of free energy change (Go) shows the adsorption process is endothermic and spontaneous. Moreover obtained positive entropy changes (So) show that an increase in randomness, is associating the adsorption of metal ions onto chitin and chitosan biopolymers.Master Thesis Hydrothermal Synthesis of Solid State Materials and Crystallography(İzmir Institute of Technology, 2004) Özmen, Bahar; Eanes, MehtapThe structure solution of the new polyoxovanadate compound([V16O31(OH)7]Cl· 15H2O), has been done by the SHELX crystal solution software. The compound was synthesized solvothermally at 170 0C in the Northwestern University. The compound crystallizes in the space group C2/c of the monoclinic system with eight formula units in a cell of dimensions a = 18.070 (2) Å, b = 17.414 (2) Å, c = 15.1154 (18) Å, â= 97.696 (2)°, V= 4713.8 (10) Å3 (T = 153 K). The structure is composed of vanadium-oxygen clusters encapsulating Cl¯ anion. Each of the V centers has square pyramidal geometry coordinated by five O atoms. The 16 (VO5) units are fused together through common edges to form (V16O38) cage with Cl¯ anion in the middle. The single crystals of the [Ni(en)3(VO3)2] compound was synthesized by hydrothermal method. [Ni(en)3(VO3)2] compound is in the crystal system of hexagonal and in the space group P61. The unit cell parameters are a = 8.9940 (13) Å, b = 8.9940 (13) Å, c = 34.001 (7) Å and á = 90 0, â = 90 0, ã = 120 0. The structure is composed of VO4 tetrahedras which are joined with others by sharing corners into infinite chains running along the c axis. The complex cation [Ni(en)3]2+ are located between the chains The chain in the compound has a repetitive sequence of 12-nuclear corner-sharing tetrahedras. The compound was synthesized at 160 0C for 3 days in the steel reaction autoclaves which have PTFE (Polytetrafluoroethylene) cups in them.Master Thesis Characterization and Genetic Mapping of Health Related Traits in Tomato(İzmir Institute of Technology, 2005) Rusçuklu, Dane; Doğanlar, SamiTomato is consumed in the daily diet and has a diverse nutritional content including antioxidants, lycopene, vitamin C and phenolics. However, the content of these compounds in tomato cultivars could be higher. There are two ways of increasing the nutritional quality of tomato. One of them is a transgenic way which is still questioned and is not approved in many countries. The other way is molecular breeding which is based on introgression of wild genes into cultivated tomatoes via the combination of classical breeding with molecular marker analysis. This method lets us obtain nontransgenic tomatoes with increased nutritional quality. In this project a population that was obtained from a cross between wild type L.pimpinellifolium and cultivated tomato L.esculentum was used. This population includes 145 inbred backcross lines (IBLs). It was expected that some individuals of this population had increased nutritional quality derived from the wild parent. In order to test this hypothesis, antioxidant activity of each line was measured. The method used to measure antioxidant activity was based on spectrophotometric measurement which gave mol Trolox equivalent antioxidant activity. It was observed that the IBLs were phenotypically close to L.esculentum and that some individuals did have higher antioxidant activity than the cultivated parent. The population was also mapped with molecular markers and 31 possible QTLs which control antioxidants in tomato were found. The source of alleles associated with increased antioxidant characters was usually L.pimpinellifolium. This result confirmed that wild type tomatoes can be a resource for increasing nutritional quality of tomatoes.Master Thesis Architecture of Societies in Multicultural Region: the Case of Vernacular Architecture at Datça Peninsula(İzmir Institute of Technology, 2005) Kaya, Can; Ergül, M. EmreMediterranean Basin is one of the oldest settlement areas in the world with its 9000 years of history. The interaction between societies, which got even stronger with the organized trade routes in the area, is the most characteristic property of the Mediterranean Basin. The Aegean and Mediterranean shores of Anatolia witnessed the shared lives of Turkish-Muslims, Greek-Orthodox, and even the Italians for more than 500 years. That's why it is possible to call this area, as "interference zone" or "transition region".One of the areas that is located on Anatolia's interference zone is Datça Peninsula. This thesis is conducted over the vernacular building stock that was built in the peninsula from the 19th century to mid 20th century. The settlements of Çeşme District and Yaka Village, are comprehended in this thesis. One roomed living units are named as main units. Main units and its fireplaces were examined. The tables, that show the size and location of the fireplace, were constituted. Analysises were done over these tables. The aim is to document the building stock in this area and to analyse on the fireplace. Consequently, it was discovered that the main units have clues belonging to Turkish Room, such as seki üstü / seki altı. It was also understood that the fireplace is the pre-condition of identifying the unit as living space.Master Thesis Isolation of Haloalkaliphilic Microorganisms From Leather Industry(İzmir Institute of Technology, 2004) Çoban, Hatice Sevgi; Yenidünya, A.FazilHaloalkalophiles are extremophilic microorganisms that are adapted to saline and alkaline conditions. Different species of them have been isolated so far from soda lakes and soil samples. Haloalkalophilic microorganisms have significant adaptive mechanisms to avoid denaturing effect of salts and to balance their interior pH. Extracellular enzymes that are produced by these halophilic and alkalophilic microorganism are applicable for industrial purposes. Therefore isolation of these organisms from their habitats and study on genotypic characterization constitute initial steps for furter biotechnological studies. In this study, processing steps of leather factories and their wastewater were chosen for sampling. In order to isolate target microorganisms Horikoshi-I medium including 12% NaCl was used. After isolation microorganisms were purified. Phenotypic tests were applied (Gram staining, catalase and oxidase behaviors, spore observation by phase contrast microscope, sensitivity to antibiotics and extracellular enzyme screenings). For genotypic characterization, genomic DNA was isolated and 16S-ITS rDNA region was amplified. Differentiation was achieved according to Restriction Fragment Length Polymorphism (RFLP) method by using Hae III and Taq I endonucleases. Isolates, which represented the different RFLP patterns, were chosen for building up the haplotype groups. As a result of the study seven different RFLP haplotypes were identified.Moreover, 16S ribosomal DNA partial sequencing was also performed on some of the strains in. These haloalkalophilic microorganisms and their enzymes could be used in different biotechnological studies in the future for various industrial applications.