This research explores the thermal stability of ZrCrAlN material system. For this purpose fourteen different compositions of ZrCrAlN coatings were deposited onto tungsten carbide substrates by using reactive cathodic arc evaporation. These compositions were further annealed at 800oC, 900oC, 1000oC and 1100oC temperatures. EDS was employed to specify the compositions. The crystal structure of the coatings were analysed by XRD, and the hardness of these coatings was determined by Nanoindentation. The experimental findings reported a significant age hardening of Zr0.16Cr0.12Al0.72N and a delayed h-AlN formation in Zr0.07Cr0.40Al0.52N. ZrCrAlN was thus proved to be thermally stable. / Multifilms,A4:2 Growth and characterization of Multicomponent Nitrides by Magnetron Sputtering and Arc evaporation

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The n-type diamond has been shown to be very difficultly synthesized by CVD method. Nitrogen as a donor impurity shows a similar atom size of carbon for diamond lattice. However, nitrogen doped diamond reveals deep level and large carrier activation energy with much defects in diamond. The application of n-type diamond has less reported and the characteristic of nitrogen doped diamond seems varied due to different fabrication process. Our previous study of nitrogen doped diamond using mixture of N2 and argon gas synthesized by microwave CVD indicated that nitrogen atoms were precipitated in the grain boundaries of diamond crystallites. In this paper, it compared the synthesis of nitrogen doped diamond using the mixed gas of nitrogen/CH4/Ar and ammonia/CH4/Ar gases by microwave CVD method for different temperature, gas flow rate, pressure, and microwave power. The conductivities, carrier concentrations and mobility of the n-type doped diamond have been analyzed and discussed. The Hall measurement shows that the mixture of gas with Ar reveals different growth mechanism and carrier transportation properties in diamond. Nitrogen atoms of N2 were located in the grain boundaries and interfaces among diamond crystallites with the sp2 structure. Nitrogen atoms of NH3 are doped into the diamond crystallites.

The phase transformation of anodized Ti film has been studied. Although X-ray diffraction detected only the amorphous TiO2 phase, transmission electron microscopy analysis showed that TiO nanocrystallites less than 10 nm in size were also present, which was further supported by x-ray photoelectron spectroscopy analysis. Anatase was found to appear gradually by annealing the as-anodized specimen in air at 500¡V550 oC, which was accompanied by a simultaneous disappearance of TiO nanocrystallites. In contrast, only rutile is formed by annealing the Ti film at the same temperatures. The results indicate that TiO can induce the formation of anatase, which is explained by the close similarity between their structures. (Chapter 1) Anatase phase of TiO2 has been shown to have very good biocompability. It was frequently observed on Ti surfaces after anodizing and thermal annealing treatments. In this report the mechanisms of the Ti to TiO and the TiO to anatase phase transitions in anodizing and annealing treatments of Ti have been studied by transmission electron microscopy. Ti thin films of two strong textures were first grown on the (001)NaCl substrates. In addition to amorphous TiO2, the anodization treatment caused the formation of TiO with an orientation relationship of (11-20)Ti // (220)TiO with Ti. The subsequent thermal annealing treatment caused the TiO to anatase transition with an orientation relationship of {200}TiO //{200}A. Pure anatase film was prepared by this method. (Chapter 2)

Geopolymers (GPs) are a new class of inorganic polymers that have been considered as good candidate materials for many applications, including fire resistant and refractory panels, adhesives, and coatings, waste encapsulation material, etc. The aim of this study is to establish relationship between structural and mechanical properties of geopolymers with different chemical compositions. The metakaolin-based geopolymers were prepared by mechanically mixing metakaolin and alkaline silicate aqueous solutions to obtain samples with SiO2/Al2O3 molar ratio that ranges from 2.5 to 5, and Na/Al or K/Al atomic ratios equal to 1. Geopolymer samples were cured in a laboratory oven at 80°C and ambient pressure for different times in the sealed containers. Structural characterization of the samples with different chemical compositions was carried out using X-Ray Diffraction (XRD), Fourier Transform Infrared (FTIR) spectroscopy, Nuclear Magnetic-Resonance (NMR) spectroscopy and Scanning Electron Microscopy (SEM) with Energy Dispersive Spectroscopy (EDS). The mechanical characterization included Micro-indentation, Vickers indentation and fracture toughness measurement, as well as compressive testing. It was found that structure and mechanical properties of GPs depend on their chemical composition. The Na-GPs with ratio 3 have a highest compressive strength and Young‘s modulus of 39 MPa and 7.9 GPa, respectively. The results of mechanical testing are discussed in more detail in this thesis and linked to structural properties of processed geopolymers.

The present study aims to investigate the composition of historical plasters to get information about their material characteristics and their technology. Plaster samples were obtained from four Ankara Citadel houses built in late Ottoman period. In order to determine the raw material characteristics and mineralogical properties of plasters / chemical analyses, optical observation of cross sections, petrographic analyses of thin sections, elemental analyses by ICP-OES, X-ray powder diffraction analyses for the determination of mineral phases, thermogravimetric analyses and FTIR analyses were carried out. Interpretation of all the analytical examination was used to understand the composition and unique character of plaster samples studied. Observation of thin sections revealed more plaster layers than those observed in cross sections. Up to twelve layers could be observed with different colours, such as blue, red, yellow, green, white and brown. Generally, thicknesses of white plaster layers were found to be thicker than the others. In two samples, two black boundaries between plaster layers were identified which could be an indication of the use of asphalt for isolation purposes, like dampness proofing or heat insulation. Soluble salt contents of the plaster samples were in the range 3.04%-9.22%, with an average being 6.62%. The anions identified were Cl-, SO42-. In few samples, PO43-, NO2- and NO3- were found. Binder was found to be lime and gypsum. The amount of binder in terms of total calcium oxide, CaO, was found to be in the range of 33.5-43.6%, with an average being 37.9%. Amount of aggregate was about 62.1% as average. The main minerals identified in plaster samples were calcite and gypsum. Gypsum might be added to increase the strength of the plaster. Beside calcite and gypsum, quartz and pozzolanic activity related mineral, Opal-A, were found in some of the samples. In red plaster layers hematite mineral was also identified. Other colour effective elements were found to be Fe, Sb, Mn, Cu, Cr and Ni. Presence of organic additives was observed but clear identification was not established.

This thesis covers the synthesis and the characterization of sodium lanthanide oxide phosphates, rare earth added strontium pyrophosphates and the Rietveld structural analysis of rare earth orthoborates. Solid state and microwave-assisted synthesis method was employed for the synthesis of desired materials. The formation of the produced phases was confirmed by X-ray Diffraction (XRD), Infrared FT-IR, Raman, Scanning Electron Microscopy (SEM) methods. By using Rietveld Refinement method, structural analysis of rare earth orthoborates were done and three dimensional crystal structures were found. In the first part of the thesis, some new sodium lanthanide oxide phosphates were synthesized by solid state reaction method from Ln2O3 (where Ln= La, Nd, Sm, Gd, Dy, Ho, Er, Yb), Na2CO3, NH4H2PO4 at 1100 oC. Na2LaOPO4, Na2NdOPO4, and Na2SmOPO4 produced with the space group is Pmm2. With the help of the same procedure new orthorhombic Na2DyOPO4, Na2HoOPO4, Na2ErOPO4, and Na2YbOPO4 were synthesized for the first time in the literature at 1100 oC with the same space group Pmm2. v In the second part of the thesis, Sr2P2O7 - ZrP2O7 solid solution was obtained by the solid state reaction and they were characterized for the first time in literature and subjected to thermoluminescence measurements showing Sr2P2O7 has glow curve around 100 oC. Then CuO and some rare earth oxides (Y2O3, La2O3, CeO2, Pr6O11, Nd2O3, Sm2O3, Eu2O3, Gd2O3, Tb2O3, Dy2O3, Ho2O3, Er2O3, Tm2O3, Yb2O3, Lu2O3) 0.5-15% (by weight) were added to pure Sr2P2O7. After structural determinations by XRD, thermoluminescence studies showed two glow peaks of Pr, Ho, and Nd along with Cu-added samples, one of them is always at around 90 oC and the other TLthermoluminescence- peak around 180, 275, and 285 oC, respectively. This study showed that rare earth added Sr2P2O7 materials can be promising material for dosimetric applications. In the third part of this work, time saving microwave-assisted synthesis method was applied to produce pure LnBO3 (Ln=La, Nd, Dy, Ho) by using urea and sucrose as a microwave active organic additive. For LaBO3 and NdBO3, space group found as Pnma and for DyBO3 and HoBO3 powders crystallized in hexagonal unit cell with P-6c2 space group. All microwave-assisted products have particle sizes lower than 1 micrometer. In the final part of this study, pure LnBO3 (Ln=Y, La, Nd, Sm, Eu, Gd, Dy, Ho, Er, Tm, Yb, Lu) powder samples were produced by using solid state reactions of Ln2O3 and H3BO3 (ratio=1:2) heated at 900 oC for 10 hours and 1000 oC for 5 hours. The crystallographic studies conducted with rietveld structural refinement and unit cell parameters, background functions, profile parameters, zero shift, atomic positions, and unisotropic thermal parameters were refined. LaBO3 and NdBO3 were solved based on Pnma orthorhombic structure while the crystal structure of YBO3, DyBO3 and HoBO3 were monoclinic C2/c. SmBO3 showed triclinic P-1 structure.

Different kinds of nanoparticles are widely used in optoelectronic and photovoltaic applications to harvest light to increase efficiency of devices. ETS-10, which is a synthetic microporous material consisting of &ndash / Ti-O-Ti-O-Ti- wires that run in the crystal in a and b directions, has been of interest in such applications due to its unique properties. In the current study, the synthesis conditions of ETS-10 were investigated in order to obtain pure ETS-10 crystals with the desired morphology. For this purpose, ETS-10 crystals were synthesized using different molar compositions. The effects of several synthesis parameters on the obtained products were investigated. Furthermore, ETS-10 thin films were prepared on ITO glass substrates using secondary growth of ETS-10 for the first time. The orientation of the -Ti-O-Ti-O-Ti- wires inside ETS-10 were explored by preparing several ETS-10 films on the ITO glass substrates using secondary growth of ETS-10 multilayers with a partial a(b)-out-of-plane preferred crystal orientation. This orientation can be desirable for the advanced applications of ETS-10 films. Afterwards, silver nanoparticle modified ETS-10 crystals were prepared and characterized in detail to understand the interaction of silver nanoparticles with the synthesized ETS-10 crystals. For this purpose, ETS-10 in the as-prepared and silver nanoparticle containing forms have been characterized using, XRD, ICP-OES, SEM, HR-TEM, N2 Adsorption, XPS, and UV/VIS spectroscopy. In order to investigate the optical properties of the silver modified ETS-10, transmittance-reflectance measurements were carried out. In general, it is believed that all steps necessary for the preparation of ETS-10 films and preliminary steps for investigating ETS-10 for future photovoltaic applications were determined.

In industrial wastewater, there are usually many kinds of organics and heavy metals and can cause damage on human health and environment without well treatment. Printed Circuit Board (PCB) industrial wastewater is a typical example due to the complicated manufacture processes and the use of specific chemicals. In this study, the PCB industrial wastewater is collected and then treated by the combination of Fenton method and Ferrite Process (or called Fenton-Ferrite Process, FFP). Moreover, the recycling possibility of sludge generated from FFP is also studied. Through this study, the treatment procedure of wastewater containing organics heavy metals is established and the direction of sludge reuse is also provided. To realize the characteristic of PCB industrial wastewater, the wastewater from some PCB factory in southern Taiwan was firstly collected and analyzed to identify the pollution concentrations and then treated by FFP. The experimental results showed that the optimum parameters of Fenton method in FFP were pH = 2, [Fe2+]= 500 mg/L, [H2O2]= 3000 mg/L, reaction time= 60 min and batch dosing, and the residual COD and TOC were 84.9 mg/L and 58.3 mg/L under the COD regulation standard 120 mg/L. Meanwhile, the proper conditions of Ferrite Process in FFP were pH= 10, reaction temperature= 80¢J, reaction time= 40 min, aeration rate= 3 L/min/L wastewater, Fe/Cu molar ratio= 10 and three-stage reaction. Under that circumstance, the residual [Cu2+] in wastewater was 0.18 mg/L and the Toxicity Characteristic Leaching Procedure (TCLP) test of sludge from FFP was 4.58 far below the effluent standard 3 mg/L and TCLP standard 15 mg/L. The properties of sludge were further investigated by X-Ray Diffractometer (XRD), Scanning Electron Microscope (SEM) and Superconducting Quantum Interference Device (SQUID). The pattern of XRD indicated that the major structures were Fe3O4 and CuFe2O4; the figure of SEM showed that the surface of sludge was composed of many round particles and the distribution of particle size was from 50 nm-100 nm; the magnetic property analyzed by SQUID showed that the saturation moment was 62.85 emu/g. In the research of sludge applied in catalytic incineration, the o-xylene conversion was 97 % by sludge but only 31 % by quartz sand at 400 ¢J. Moreover, in the 72 hr-decay test of catalyst, the results clearly indicated that the performance did not obviously decline and there were no any byproducts but CO2. Therefore, the investigation revealed that the sludge had great potential in catalytic reaction. The catalytic performance of various ferrospinels generated from different manufactured conditions was also studied. Through the screening of catalysts, the order of various ferrospinels activity was Cu-ferrite > Mn-ferrite > ferrite ¡Ü Zn-ferrite and the most effective Cu-ferrite was manufactured at pH= 9 and T= 90 ¢J. After 72 hr test, the decay of catalyst was not also found. In the examination of Cu-ferrite physical property, the XRD pattern showed that the structure was CuFe2O4; the figure of SEM illustrated that there was no difference between the surface of fresh and used catalyst; the magnetic property measured by SQUID showed that the saturation moment was 30.89 emu/g.

Magnetische Formgedächtnsilegierungen haben die besondere Fähigkeit, sich im äußeren Magnetfeld zu verformen. Dies geschieht aufgrund von Zwillingsgrenzenbewegung in der martensitischen Tieftemperaturphase. Da der Effekt bislang an Einkristallen untersucht wurde, ist es das Ziel dieser Arbeit, den Effekt an polykristallinen Proben nachzuweisen. Dafür wurden Proben nach dem Prinzip der gerichteten Erstarrung präpariert. Deren Kristallstruktur wurde durch geeignete Zusammensetzung und Wärmebehandlung einphasig eingestellt. Mechanisches Training und weitere Wärmebehandlungen ermöglichten schließlich die Demonstration der magnetischen Dehnung von ca. 1 % an polykristallinen Proben. Durch zusätzliche Einkopplung akustischer Wellen konnte die Dehnung auf 2,2 % gesteigert werden.