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In this study, photocatalytic degradation of 2,4 Dichlorophenoxyacetic acid (2,4D), one of the the most used pesticide, was investigated by TiO2 photocatalyst produced by sol-gel method. Three different parameters (Titanium isopropoxide (TIP) amount, HNO3 concentration and aging time) were investigated and modelled by applying Box Behnken Experimental Design method for optimum TiO2 synthesis. Photocatalyst production process was optimized by examining the 2,4D photocatalytic degradation rate of TiO2 photocatalysts produced under different process conditions. TiO2 samples, which were synthesized with the optimum conditions, were characterized by XRD (X-ray Diffraction), SEM (Scanning Electron Microscope), zeta potential, particle size analysis, and also compared with commercial Degussa P25 TiO2 photocatalyst. 2,4D photocatalytic degradation rate was determined as 0.0084 min-1 for the optimum condition 1 (TIP amount: 24.08 mL, HNO3 concentration: 3.53 M, aging time: 2.29 hours) and 0.0085 min-1 for the optimum condition 2 (TIP amount:10.33 mL, HNO3 concentration: 0 M and aging time: 19.51 hours). The amount of used acid was reduced to zero or the aging time was reduced to the lowest value (2.29 h) by optimizing the TiO2 production parameters via experimental design methodology, hence, a very high photocatalytic efficiency was obtained. [ABSTRACT FROM AUTHOR]

Adhesion it is known that the bond strength varies depending on the interaction of the material surfaces with each other and the surface morphology of the samples. Sufficient surface conditions are required to achieve good adhesion. It is important how the surface morphology, roughness values and free surface energy (SFE) values affect the bond strength and the relationships between these values. The aim of this study was to investigate the relationship between surface morphology, roughness values, contact angle and SFE values of hybrid etched surfaces with chemical etching, sandblasting and both sandblasting and chemical etching. Different surface morphologies were formed of the surfaces etched with different techniques. Contact angle values were determined by using different liquids on the surface of the samples with different surface morphologies. In addition, the surface morphology of the etched AA7075 samples was analyzed by scanning electron microscope (SEM) and 3D profilometer, and surface roughness values were determined.Different surface morphologies of the etched surfaces were formed by different techniques. The SFE values of the surfaces give us information about how wettable the surface is. For this reason, the surface roughness andn SFE values of AA7075 surfaces were compared and the mechanical and thermodynamic relations of the surfaces were revealed in the study. OWRK and Zisman methods were used in the calculations of SFE and it was seen that the values obtained from the two methods were consistent with each other. The highest SFE values were obtained on hybrid etched surfaces with sandblasting+0.5M NaOH and sandblasting+1M NaOH. Surface roughness values took different values in each surface treatment. As a result, it is seen that there is no direct relationship between surface roughness values and SFE. [ABSTRACT FROM AUTHOR]

In the study, the removal performance of arsenic and antimony by drinking water treatment sludge (DWTS) was investigated. DWTS-200 was produced by thermal modification of the DWTS at three different temperatures (200, 400 and 600℃). The maximum arsenic removal was obtained at 200℃ and 1 hour contact time. The surface area and pore volume of adsorbent were analyzed by BET method; phase compositions were determined by X-ray diffraction (XRD), surface morphologies and elemental analyses were performed by scanning electron microscope (SEM) and energy disperse X-ray spectroscopy (EDS). The results showed that adsorbent had a relatively high surface area (170 m2 g-1) and was predominantly amorphous. The predominant phases were iron, calcite, oxygen, and quartz. The breakthrough volumes were obtained as 6,000 L (133,000 BV) and 640 L (14,000 BV) for 40 μg As L-1 and 80 μg Sb L-1 inlet concentrations. In order to determine the kinetic parameters and predict the breakthrough curves for column design, Thomas and Yoon-nelson models were applied. The column experimental data were fitted well to each model. The maximum adsorption capacity was calculated by Thomas model as 6.53 mg Asg-1, 5.21 mg Sbg-1. Regeneration studies were also shown that DWTS-200 could be reused after regeneration. [ABSTRACT FROM AUTHOR]

Expanded polystyrene (EPS) trays are widely used for food packaging and serving because they are light and inexpensive. However, their use has been banned or restricted in many parts of the world due to its negative effects on the environment. In recent years, many studies have been carried out on the production of biodegradable foam trays. Although starch-based foam trays are promising in terms of being biodegradable and having sufficient mechanical resistance, the most important obstacle in their commercial use is that they are not sufficiently resistant to water. In this study, foam trays were produced by adding wheat fiber at a ratio of 7% of starch after wheat starch or mixture of wheatpotato starch was cross-linked with glyoxal. Foam trays were coated by using solutions of polylactic acid (PLA), polycaprolactone (PKL), and polymethyl methacrylate (PMMA). Scanning electron microscope images showed that coating materials formed a 30-40 µm thick layer on the surface of foam trays and making the surface of trays smoother. The average density of foam trays produced from wheat potato starch was 0.120±0.01 g/cm3, which was lower than that of trays produced from wheat starch (0.157±0.02 g/cm³ ). The coating of trays produced from wheat starch with PKL and PLA, and wheat-potato starch with PLA and PMMA did not change the density of trays. Foam trays coated with PLA and PMMA absorbed 12 and 18 times less water than control trays, respectively. The trays made of wheat-potato starch coated with PMMA absorbed only 2.3% of water after 300 minutes, showing that they could be particularly suitable for packaging foods with a high water content. Trays coated with PCL under simulated soil were found to break down on the day 42, and those coated with PLA on the day 84. It was determined that 12.2% of the initial tray weight of trays coated with PMMA remained intact on the 84th day. [ABSTRACT FROM AUTHOR]

Magnesium alloys; It is widely used in metallic biomaterials with its low toxic effect and biodegradability. Although these alloys help the formation of new tissues in the body, they provide great advantages over other metallic biomaterials due to their ability to dissolve from the body after the area of use has healed. However, due to their low corrosion resistance, they cause it to dissolve in the body before the treatment process is completed. This is the major disadvantage that limits the use of magnesium alloys. Various surface modification methods are applied to magnesium alloys in order to eliminate this disadvantage. Micro Arc Oxidation (MAO) method, which can provide a coating resistant to wear and corrosion, is one of the surface modification methods applied to improve the surface properties of magnesium alloys. In this study; Composite oxide coatings with Ag nanoparticle and Hydroxyapatite were grown by MAO method. Morphological properties of the coatings were determined by Scanning electron microscope and X-Ray Diffraction instruments. The antibacterial properties of Ag nanoparticle and HA doped composite oxide layer which were grown by MAO method and the biodegradability of the coated/uncoated materials in the blood plasma were investigated. As a result of the experiments, the development of bacterial activity in the sample coated by MAO was prevented by adding Ag nanoparticle and Hydroxyapatite to the electrolite solution. In addition, the biodegradation rate has been reduced by surface treatment on AZ91 Mg Alloy. As a result of the soaking test in blood plasma, it was determined that AZ91 Mg alloy protects itself against dissolution with a rate of approximately 89%. [ABSTRACT FROM AUTHOR]

In this study, sodium alginate/poly (vinyl alcohol)/clinoptilolite composite membrane was obtained for the separation of dimethylformamide/water mixture by pervaporation method. Cross-linked membranes were characterized by Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), thermal gravimetric analysis (TGA) and scanning electron microscope (SEM) instruments. Although the flux value (3.266 kg/m2 h) was found to be high, the desired result for selectivity could not be achieved. The activation energy for the 20% by weight DMF solution was measured as 3,720 kcal/mol. The effect of zeolite addition on membrane performance was investigated. [ABSTRACT FROM AUTHOR]

In this study, the effect of gas cementation, tempering and deep cryogenic treatment with different holding times (24, 36, 48 hours at -196 °C) on the corrosion behavior of cementation steel in 3,5% NaCl environment was investigated. The corrosion tests of the samples classified in five different groups were examined with the Electrochemical Impedance Spectroscopy (EIS) method, the degradation of the metal surface was visually investigated with the Scanning Electron Microscope (SEM), and the chemical composition of the surface was determined by Energy Dispersive X-ray Spectroscopy (EDS). The findings show that cementation, tempering and cryogenic treatment applications reduce the corrosion rate of cementation steel. It has been demonstrated by electrochemical and surface imaging methods that the N3 sample, which applied deep cryogenic treatment with 24 hours holding time after cementation, is much less corroded in 3,5% NaCl environment than other samples. [ABSTRACT FROM AUTHOR]

Objective: The purpose of this study is to evaluate the bond strength of different repair systems by using composite resin and ceramic cementation repair methods to zirconia-based ceramics. Material and Method: All-ceramic blocks (IPS Empress II; Ivoclar Vivadent, Schaan, Liechtenstein) sized 4.00 mm in length, 5.4 mm in width, and 3.00 mm in height were fabricated by dental laboratory as thirty specimens. CAD/CAM zirconia blocks (n =40) (Prozir; SeramDent, Turkey) sized 5.00 mm in length, 5.4 mm in width and 13.0 mm in height by CEREC System were fabricated from fully sintered Y-TZP core. Zirconia specimens were randomly divided into seven groups for the following different intraoral repair systems(Clearfil, Cimara Zircon, Bisco) and a control group. Every ten specimens were repaired as same sized. Control group was fabricated by conventional firing as unbroken solid zirconia ceramic samples. Each specimen underwent 5000 cycles of thermocycling. The SBSt (Shear bond strength test) was performed by loading force on the repaired piece to record load-to-failure. Failure mode was evaluated using a digital microscope and SEM. SBSt data were analyzed using one-way ANOVA and Tukey’s HSD test. Results: Clearfil and Cimara Zircon systems significantly increased the bond strength for composite resin method when compared with the Bisco system (respectively p <0.001, p =0.001). All-ceramic method significantly increased the bond strength when compared with the composite resin in Bisco system (p <0.001). Conclusion: Although the composite restoration method is effective for repair, the all-ceramic/zirconia repair method can be an option for repairing layered zirconia restorations. [ABSTRACT FROM AUTHOR]

In this study, additive manufacturing technique was preferred to produce Wolfram (W), Silicon (Si), and Molybdenum (Mo) doped Co-Cr biomedical alloy. In biomedical applications, the alloy consisting of Wolfram (W), Silicon (Si), Molybdenum (Mo), Chromium (Cr), and Cobalt (Co) elements as known for its high wear and good corrosion resistance. Two group of Co-Cr-Mo alloys were produced using the Selective Laser Melting (SLM) method, one of the additive manufacturing manufacturing techniques. One of the produced samples was then subjected to a secondary heat treatment process. The microstructures of the produced alloys were investigated using X-Ray diffractometry (XRD), Energy dispersive X-Ray analysis (EDX) and scanning electron microscope (SEM). Then, the mechanical properties of the alloys were analyzed by electrochemical corrosion test, microhardness test and Archimedes principle density measurement were the final tests. The data obtained as a result of the analyzes showed that a homogeneous microstructured Co-Cr-Mo alloy was produced by the additive manufacturing production technique. In addition, heat treatment caused serious changes on the microstructure and mechanical properties of the material. The most important of these changes was the reduction of the grains forming the alloy, resulting in an increase in the microhardness value of the alloy. [ABSTRACT FROM AUTHOR]

In this study, the CuO thin films were deposited on glass substrates at different substrate temperatures (350, 400, 450, and 500 C) by the ultrasonic spray pyrolysis (USP) method and then annealed at 525 C. In X-ray diffraction (XRD) analysis, the peak intensity was not found in thin films at 350 C substrate temperature and as-grown conditions. Two distinct peaks were observed at 36 and 39 in the XRD patterns of other films. These peaks are characteristic peaks of the monoclinic crystal structure of CuO. Atomic force microscopy (AFM) and scanning electron microscope (SEM) images of the produced thin films were examined. The surfaces of thin films are not smooth. After annealing, grain agglomerations were formed. The optical properties of the CuO thin films were analyzed by ultraviolet-visible region (UV-Vis) measurements. Forbidden band gap values (Eg) were calculated from Tauc graphs for as-grown and annealed samples. It has been observed that the structural, morphological, and optical properties of CuO thin films produced by the USP method can be controlled by the substrate temperature. [ABSTRACT FROM AUTHOR]

In this study, an electrochemical sensor based on carbon nanotube immobilized with diester-functionalized calix[4]arene (CNT-Calix-DE) was developed to determine the ondansetron content in pharmaceutical preparations. During the sensor preparation stage, the glassy carbon electrode surface was modified with CNT-Calix-DE. The surface morphology, electrochemical characterization and analytical performance of the sensor were examined using scanning electron microscope (SEM), electrochemical impedance spectroscopy (EIS) and differential pulse anodic stripping voltammetry (DPASV). Under optimal experimental conditions, the developed sensor showed a linear response to ondansetron in the concentration range of 1.0-10.0 M. Analytical applicability of the sensor was investigated by determination of ondansetron in pharmaceutical preparations. [ABSTRACT FROM AUTHOR]

In this study, the effects of the addition of chia and flaxseed gel as egg white replacers on the rheological properties of pancake batter and some quality properties of pancake samples were investigated. Chia and flaxseed gel were used in two different proportions (50%, 100%) as egg white replacers. It has been revealed that the flow behavior properties of pancake batters can be explained by the power law model (R2=0.987-0.998) and the samples exhibited shear-thinning behavior. The use of chia and flaxseed gel increased the elastic (Gˈ) and viscous modulus (G") values. It was determined that the protein content decreased with increased ratio of chia and flaxseed gel (P <0.05). By examining the scanning electron microscope images, porosity of the samples decreased with the increase of chia and flaxseed gel, and the samples showed a more layered and fragile structure with the increase of chia seed gel. [ABSTRACT FROM AUTHOR]

In this study, it is aimed to produce nanofibers via electrospinning method using a polymer solution doped with β-arbutin, which is known as an agent reducing skin blemishes. For this purpose, β-arbutin was added to the polyamide 6/formic acid solution with chosen concentrations as 2%, 5%, and 10% (w/v). After preliminary electrospinning process, scanning electron microscope (SEM) analysis was performed to determine the optimum spinning parameters. The SEM images presented that nanofibers with uniform morphology were obtained with the 2% (w/v) β-arbutin concentration. Three different voltages were applied for 2% (w/v) β-arbutin added solution and the best morphology was obtained by 30 kV voltages. According to the statistical analysis performed, it was seen that the mean diameters of nanofibers varied due to the β-arbutin concentration. In this study, it has been demonstrated that the thin and light nanofiber textile surfaces containing skin blemishes reducing agent can be produced via electrospinning method to be used as a cosmetic textile product. [ABSTRACT FROM AUTHOR]

Magnetite (Fe3O4), Humic Acid (HA) and Silver (Ag) are materials with important properties. Synthesizing a single material which will have all the properties of these materials can provide significant advantages for some application areas. In this study, synthesized Fe3O4@HA@Ag was doped into poly(vinyl pyrrolidone) (PVP), in weight ratios of 5%, 7.5% and 10%, and nanofiber production was carried out by electrospinning method. Structural properties of nanofiber structures were investigated by X-ray Diffraction (XRD), morphological properties by Scanning Electron Microscope (SEM), spectroscopic and thermal characterizations by Fourier transform infrared (FTIR) and Thermogravimetric Analysis (TGA). When the analysis results of nanofibers were evaluated, it was determined that Fe3O4@HA@Ag doped PVP nanofibers were successfully produced. [ABSTRACT FROM AUTHOR]

In the study, the micromorphology of labellum in samples belonging to 10 different Ophrys taxa was examined by Scanning Electron Microscopy (SEM) method and the results were presented in comparative tables. While the samples were collected from the field, they were taken to 70% alcohol, some of them were dried according to the herbarium rules and identified. The labellum samples extracted from alcohol were dissected under the stereomicroscope with scalpel and needles and placed directly into the iron apparatus of the SEM device with double-sided adhesive tapes. These samples, whose alcohol was completely evaporated by waiting for one night, were examined directly with Scanning Electron Microscope (SEM) and labellum microphotographs were taken. According to our findings, it was determined that the speculum structures are very different from each other, and the shape and distribution of the hair / papilla in the basal, median and lateral regions differ from species to species.It was also determined that the apex region differs in O. fusca, O. lutea, O. speculum, O. mammosa, O. pseudomammosa, O. heldreichii, O. umbilicata, and O. holoserica species. In summary; It was concluded that the labellum speculum and apex structure of the 1st degree and the basal, median and lateral region surface characteristics of the 2nd degree differ widely between the species. [ABSTRACT FROM AUTHOR]

Bimetallic or layered materials are an important group of advanced engineering materials, which are the materials where the physical, mechanical and thermal properties of the core particle can be improved. Therefore, in this study, the fabrication of silver-plated copper bimetallic particles was investigated by electroless coating method. Moreover, in this study, the effect of the amount of ion trapping / reducing agent in the electroless coating method on the physical properties of the bimetallic particles obtained as a result of the coating was investigated. Morphology, microstructure and silver layer thickness of the silver coated copper particles were characterized by scanning electron microscope (SEM) and Xray diffraction. SEM investigations revealed the presence of a silver coating layer on copper particles in the range of 0.873 - 2.3 μm. This result showed that the silver coating layer can be successfully synthesized on copper particles by using the electroless coating method. Thus, low cost of copper and high thermal conductivity and oxidation resistance of silver are combined in a single metal particle. [ABSTRACT FROM AUTHOR]

In the study, Spray pyrolysis technic was used to grow Ag-doped CdO thin films on Indium Tin Oxide (ITO) substrates. Temperatures of ITO substrates were fixed at 400⁰C. The structural and morphological properties of the thin films were investigated by X-Ray Diffraction (XRD) and Scanning Electron Microscope (SEM) devices. According to XRD results, the thin films have polycrystalline cubic structure and the average crystal sizes of thin films with Ag dopant are around 23 nm. According to Scanning Electron Microscope (SEM) images, changing of Ag dopant ratio does not effects surface morphology of samples significantly. [ABSTRACT FROM AUTHOR]

According to the subjects covered, oil painting canvas are one of the most important movable cultural heritage that provide information about the art, style, social life, belief and history of the period. In this study, it was aimed to clean the dirt due to various reasons on oil canvas by using biopolymeric hydrogels. Hydrogels have many advantages in that they don't contain toxic substances and can be prepared with a fast and easy technique. The dirt on the canvas paintings that are historical artifacts were cleaned without damaging the building with the hydrogels prepared. Hydrogel structure was prepared as a cleaning material with plentiful and readily available alginates and natural gums biopolymers. The canvases aged by chemical methods were contaminated with dust, ash and soot to test the cleaning processes. As a result of the application of the hydrogel materials used on polluted and aged canvases, the results were analyzed with different microscopic and spectroscopic methods. The characterization of the materials was carried out using analysis methods as optical microscope, Scanning Electron Microscope (SEM) and Fourier Transform Infrared Spectrophotometer (FT-IR). [ABSTRACT FROM AUTHOR]

Conjugated linoleic acid (CLA) is a functional compound that has many positive effects on human health. However, its low oxidation stability and water-solubility properties limit the use of this component in foods. In this study, the effects of different ratios of skimmed milk powder and maltodextrin on microencapsulation yield and microencapsulation efficiency were investigated in the microencapsulation of an oil-rich in CLA by spray drying. Microencapsulation yield and microencapsulation efficiency were determined in the range of 21.35-42.92% and 16.32-73.91%, respectively. According to the data obtained, the optimum coating material ratio was determined as a mixture containing 70% skimmed milk powder and 30% maltodextrin. In addition, the molecular, morphological, and thermal properties of the capsules obtained at this point were characterized using Fourier transform infrared spectroscopy (FTIR), scanning electron microscope (SEM), and thermogravimetric analysis (TGA). [ABSTRACT FROM AUTHOR]

This research covers investigation of mode-I fracture toughness of the recycled waste mussel shell particles reinforced epoxy composites. Vacuum assisted resin infusion molding (VARIM) method was applied to produce composites. The aim of the research is to use recycled waste shells to reduce production cost and to prevent environmental pollution. VARIM was applied to produce fiber reinforced composite. Therefore, as reinforcement particles mussel shell, and as particle reinforced composite production method VARIM are both two new points of the research. Mode-I fracture toughness experiments conducted according to ASTM D 5045 standards with single-edge-notch bending specimens for six repeats. According to mode-I tests, the fracture toughness of the mussel shell particle reinforced epoxy composites is 2.44 MPa∙m1/2. The failure region from one of the tested specimen was investigated by scanning electron microscope (SEM) in the next section of the paper. After the test results are given by diagrams, they are discussed according to other particle-reinforced composites to show the new material place in the literature by means of fracture toughness. [ABSTRACT FROM AUTHOR]

In this study, CH3NH3PbI3-xClx perovskite thin films were deposited on glass substrates by the ultrasonic spray pyrolysis method. The effect of substrate temperature on the structural, morphological and optical properties of perovskite films was investigated using an Xray diffraction (XRD) device, scanning electron microscope (SEM), atomic force microscope (AFM), and Uv-Vis spectrophotometer. When the X-ray diffraction spectra were observed, it was determined that all films were formed in the tetragonal perovskite lattice structure, but it was observed that different undesirable crystal structures were formed in thin films with 75 °C and 100 °C substrate temperatures. Although no post-annealing process was applied to the films, it was determined that the films coated at 125 ° C substrate temperature were in the form of perovskite that has CH3NH3PbI3-xClx structure, which are exactly compatible with the literature. The crystal sizes of thin films were determined by using XRD spectrum data and Debye-Scherrer formula. The highest crystal size was obtained as 743 Å for the thin film deposited at a substrate temperature of 125 °C. When the SEM images were examined, it was determined that the film surfaces were homogeneously coated at only 125 °C substrate temperature and that there were very little voids between the crystal particles. The surface roughness of the films was examined by atomic force microscopy system, and the smoothest surface roughness was obtained in the thin film deposited at 125 °C substrate temperature with 41.32 nm. Optical absorption studies were carried out by using a Uv-Vis spectrophotometer operated at room temperature. It was observed that as the substrate temperature applied while coating the films increased, the forbidden bandgap of the film increased from 1.20 eV to 1.56 eV, which is also compatible with the theoretical analysis. [ABSTRACT FROM AUTHOR]

In this study, the effect of gas pressure on the shape and size of AM60 magnesium alloy powder produced by the gas atomization method has been experimentally investigated. The experiments were carried out at a constant temperature of 820°C with a 2 mm nozzle diameter and 4 different gas pressures (5, 15, 25, 35 bar). Argon gas was used to atomize the melt. In order to determine the shape of the AM60 powder produced, scanning electron microscope (SEM), XRD, XRF and SEM-EDX analysis were used to determine the phases formed in the internal structures of the powders and the% ratios of these phases, and laser measuring device was used for the powder size analysis. Hardness tests were performed to determine the mechanical properties of the powders produced. The general appearance of the AM60 alloy powders produced was ligament, acicular, droplet, flake and spherical in shape, but due to the increase of gas pressure, the shape of the powders changed mostly towards flake and spherical. It was determined that the finest powder was formed at 820°C, 35 bar gas pressure at 2 mm nozzle diameter and the powder was generally complex. [ABSTRACT FROM AUTHOR]

Nowadays, higher performance expectations from turbines and internal combustion engines, rapid extinction of fossil fuels, global warming and increasingly tighter emission standards worldwide are the biggest problem of engine manufacturers. The most important solution approach for this problem is the coating of metallic parts of turbine blades and/or combustion chamber with a thermal barrier coating material having low thermal conductivity. This solution leads to significant improvements in engine performance and efficiency. On the other hand, rare element doped new generation ceramic thermal barrier coating material materials having low thermal conductivity have attracted considerable attention in recent years. In this study, the metallic bond layers have coated on the metallic substrates by using high-speed oxy-fuel spraying method and then La2Zr2O7 based ceramic top layers have coated as double layered by using atmospheric plasma spraying method. In the scanning electron microscope analyses, it was found that the thicknesses of the ceramic top layers ranging from 375 to 480 μm and the porosity values were among 10.2 and 12.5%. Moreover, the interfaces between the layers were continuous and there was no metallographically problem. Therefore, it is understood that, La2Zr2O7 based ceramics were successfully coated. In addition, X-ray diffraction analysis revealed that there was no phase transformation or chemical degradation after atmospheric plasma spray process. [ABSTRACT FROM AUTHOR]

In this study, a new route was proposed for electrochemical synthesizing of TiO2 doped diamond-like carbon (DLC) nanocomposite film. To obtain TiO2 doped DLC nanocomposite film, firstly, titanium metal was dissolved in hydrogen peroxide (H2O2). Then, the obtained solution and methanol were mixed with the volume ratio of 1:200 and electrolyzed in a two-electrode cell. The obtained film was characterized by scanning electron microscope (SEM), Raman spectroscopy, X-ray photoelectron spectroscopy and X-ray diffraction. SEM image showed homogeneous and porous film. Raman spectroscopy indicated that TiO2 doping leads to sp3 hybridized carbon bonds. XPS analysis confirm TiO2 doping and sp3 bonds. In the XRD spectrum, the observed peaks attributed to hexagonal carbon structure. The obtained results show that DLC nanocomposite film containing high amounts of sp3 bonds can be successfully produced by the electrochemical method. [ABSTRACT FROM AUTHOR]

The snake skin is made of a elastic inner layer and a durable and inelastic outer surface. Snakes shed the whole outer layer, which is also known as the stratum corneum, several times a year. This layer, which is also known as shed snake skin, is used in folkloric medicine, cosmetics, and pharmacological studies. The objective of this study is to compare the morphological characteristics of stratum corneum layers of two different snake species living in the same habitat with a scanning electron microscopy and to show that this method can be used in taxonomy. A total of 6 "shed snake skin" consisting of three of Dolichophis jugularis and three of Malpolon insignitus were included in the study. We determined that there were morphological differences between "shed snake skin" of two different species, which were examined by scanning electron microscope. In light of the study results, we conclude that the "shed snake skin" might be used in the taxonomy as an alternative method. [ABSTRACT FROM AUTHOR]

In this study, one binary Al-25n alloys and eleven ternary aluminum-zinc-titanium alloys, Al-25Zn-0.01Ti, Al-25Zn-0.03Ti, Al-25Zn-0.04Ti, Al-25Zn-0.05Ti, Al-25Zn-0.075Ti, Al-25Zn-0.1Ti, Al-25Zn-0.2Ti, Al-25Zn-0.4Ti, Al-25Zn-0.6Ti, Al-25Zn-0.8Ti and Al-25Zn-1Ti, were produced by permanent mold casting method. Structural, mechanical, and corrosion properties of the tested alloys were investigated. Structural investigations were carried out with scanning electron microscope (SEM) and X-ray diffraction (XRD) studies. Mechanical properties of the alloys were determined with the Brinell hardness and tensile tests. Corrosion tests were carried out with electrochemical test setup in accordance with ASTM G5 standard. Al-25Zn and Al-25Zn-Ti alloys were composed of α and η phases as the main matrix, and it was observed that Al3Ti phase began to precipitate in the microstructure when the titanium content exceeded 0.01%. In addition, the size of dendrites or grains of the Al-25Zn-Ti alloys was found to be much smaller than that of binary alloy. The hardness, yield strength, and tensile strength values of the Al-25Zn alloy significantly increased with the 0.01%Ti addition, but when Ti content exceeded 0.01%, these values decreased with increasing titanium content. It was observed that titanium addition had a negative effect on the corrosion properties of the Al-25Zn alloy. The change on the mechanical and corrosion properties of the Al-25Zn alloy due to the titanium addition in different ratios have been explained based on the structural properties of the alloys. [ABSTRACT FROM AUTHOR]

In this work, rice husk and burned rice husk were used as low cost adsorbents to remove a cationic dye, Basic Yellow 51(BY51), from aqueous solution by adsorption. Characterization of rice husk and burned rice husk was carried out with Scanning Electron Microscope and Fourier Transform Infrared Spectroscopy. The effects of operational parameters on the efficiency of dye removal including initial dye concentration, contact time, pH, and temperature were investigated. All series experiments were carried out in batch mode. Equilibrium data were analyzed using Langmuir and Freundlich isotherm models and monolayer adsorption capacity was calculated. Kinetic data were studied using pseudo first order and pseudo second order kinetic models and dye removal was found to follow the pseudo second order kinetic model closely. Thermodynamic parameters such as enthalpy change (H°), entropy change (S°) and free energy change (G°) were also investigated. Free energy change showed that adsorption of Basic Yellow 51 was spontaneous at all studied temperatures for rice husk and burned rice husk. It is proposed that rice husk and burned rice husk may be suitable as adsorbents for removal of cationic dyes from aqueous solution. [ABSTRACT FROM AUTHOR]

In this study, pollen morphology of some endemic species belonging to Scrophulariaceae family and their distribution limited to Erzincan was studied by using Scanning Electron Microscope (SEM). Pollen sizes, pollen types, pollen patterns, polen ornaments and apertures tructures of Scrophularia erzincanica, Scrophularia fatmae, Verbascum leiocarpum, Verbascum ozturkii were investigated. In both Scrophularia species pollen size is medium and polen types tricolpat. Although pollen form of two species is close to each other, Scrophularia erzincanica was found to be subprolate and in Scrophularia fatmae it was perprolate. Ornamentations were determined as verrucat and reticulat respectively. In the study of Verbascum species; In the two types studied, it was found that the pollen size was medium-sized, the pollen shape was spherodial in Verbascum leiocarpum, the subprolate was Verbascum ozturkii, the polen types were tricolpate and their ornamentations were reticulate. When the findings of the studied species are evaluated, it is thought that polen morphologies in Scrophularia speciesare not enough to be used in the differentiation of taxa, and Verbascum species shows differences in polen type and it can be used in distinguishing taxa in this context. [ABSTRACT FROM AUTHOR]

Pisolithus arrhizus (Scop.) Rauschert (Basidiomycetes) type is an ectomycorrhizal fungi found in the soil that surrounds many species of eucalyptus and pine trees. In this study, it was aimed to determine the inhibitory effect of Titanium (TiO2) nanoparticle (NP) prepared by using Pisolithus arrhizus ethanol extract on different pathogenic microorganisms. In the study, NP's synthesized using hydrothermal method was characterized by UV-vis spectrometer (UV-vis) and scanning electron microscope (SEM). The antimicrobial activity of these prepared and characterized NP's, have been investigated by using disk diffusion method on test pathogens of Staphylococcus aureus, Bacillus subtilis, Escherichia coli, Candida albicans and Streptococcus mutans. While NPs have a weak inhibitory effect on pathogens (7.5-9.3 mm), the maximum inhibition (9.3 mm) is shown against S. mutans. Whereas antifungal effect against C. albicans have not been found. [ABSTRACT FROM AUTHOR]

Purpose: In this study, it was aimed to immobilize urease from Canavalia ensiformis onto modified Florisil (magnesium silicate) by covalently and to characterize immobilized urease and also to investigate reusability of immobilized urease in a batch type bioreactor.Materials and Methods: Florisil was activated with 3-aminopropyltriethoxysilane and then modified with glutaraldehyde. Urease was covalently immobilized onto modified support. Images of support and immobilized urease were examined on a scanning electron microscope. The optimum pH and temperature, kinetic parameters (Km, Vmax, kcat/Km) and storage stabilities at 4°C and room temperature of free and immobilized ureases were determined. Reusability of immobilized urease was investigated in a batch type bioreactor.Results: Free and immobilized ureases showed their maximum activities at pHs 7.0 and 6.5, and at temperatures 50 and 60°C, respectively. The Km value of immobilized urease increased 2.2 fold compared to free urease. The catalytic efficiency of immobilized urease was about 0.1% of the free urease. Free urease completely lost its activity at the end of 5 days stored at 4°C and room temperature; however, immobilized urease did not lose its activity at the end of 19 days at the same conditions. Immobilized urease maintained 50% of its initial activity at the end of 10 reuses in batch type bioreactor.Conclusion: Although urease activity significantly decreased upon covalent immobilization onto modified Florisil. However, high storage stability and reusability of immobilized urease makes it potentially useful immobilized form. [ABSTRACT FROM AUTHOR]

3-Dimensional (3D) printable polymeric structures have lower mechanical properties than parts produced by existing conventional methods. It is still a challenge to obtain high elongation and more ductile on 3D polymeric structures even though photocurable resin cross linked with among polymer chains during UV-irridation and applied post-heat treatment steps. Filler materials as reinforcement agents such as silica, alumina, zirconia and multi-walled carbon nanotube, graphene, etc. were used to enhance its mechanical properties in the past decades. In this study, montmorillonite nanoclays including amine and silane functional group, which provides high dispersibility and homogeneity in photocurable resin, are added and mixed into acyrlate based photocurable resin with four different (pure, 0.25%, 0.5% and 1%) concentration. By using a 3D laser stereolithography printer, test samples are produced and characterized by tensile test, dynamic mechanical analyzer (DMA) and scanning electron microscope (SEM). As a result, it has been observed that by increasing the concentration of nanoclay, 3D polymeric structures gradually enhances its mechanical strength compared to pure polymer structures. Due to the agglomeration observed on %1 nanoclay concentration, their mechanical strength is lower than that of 0.5% nanoclay. Also, thermal stability gradually decreases with increasing nanoclay concentration due to its insulating properties. [ABSTRACT FROM AUTHOR]

In this study, Ni-Co alloy coatings were prepared on the steel substrates with electrodeposition method from a sulphate baths using power supply. The effect of Co content in electrolyte on the composition, phase structure and surface morphology of alloy coating were investigated. The prepared coatings were characterized using X-ray diffraction (XRD) and scanning electron microscope (SEM). According to the results, Co concentration in the electrolyte affects the properties of the Ni-Co alloy coating layer. There is a serious increase of Co content deposited Ni-Co alloy coating when the Co concentration is increased in the electrolyte. The both FCC and HCP crystal structures of Ni-Co alloy coating layer began to transformin into HCP structure with increasing amount of Co content. At the same time, a change in the surface morphology was observed with an increase in Co ratio in the alloy coating layer and a more granular structure was formed. [ABSTRACT FROM AUTHOR]

Undoped and Erbium (Er) doped zinc oxide (ZnO) films were prepared on p-Si substrates by sol gel method using spin coating technique. The effect of Er dopant on the structural, morphological and optical properties of ZnO film was investigated by X-ray diffractometer, scanning electron microscope (SEM) and UV-vis spectrophotometer, respectively. From X-ray diffraction (XRD) spectra, the films were crystallized in hexagonal wurtzite structure in zincite phase. The structural parameters such as grain size, dislocation density, lattice parameters, strain and stress were calculated. From the SEM images, it is seen that the film surfaces are well-coated, uniform, without cracks and pores. ImageJ program was used to investigate the average particle size, grain boundaries and the surface of the films. The optical properties were studied by diffuse reflectance spectra measured by UV-vis spectrophotometer and the optical band gap values were determined by differential reflectance and Kubelka-Munk theory. In both methods, it was determined the optical band gap value of ZnO film increases or decreases irregularly with the Er content. It was observed that the optical band gap of the 0.4% Er doped ZnO film was larger than the other films. [ABSTRACT FROM AUTHOR]

In this study, the effect on the efficiency of CdS/CdTe solar cell with MoO3 buffer layer was examined. Two sample was grown as Cam/FTO/SnO2/CdS/CdTe/Au and Cam/FTO/SnO2/CdS/CdTe/MoO3/Au. MoO3 layer was deposited as a buffer layer between CdTe and metal electrode in the back contact of CdTe solar cell. Solar cells were grown on glass/fluorine tin oxide substrate by Sputtering system. The morphological properties of CdS/CdTe solar cell structure with MoO3 buffer layer have been evaluated by means of scanning electron microscope (SEM) and atomic force microscopy (AFM) measurements. In addition, the cell device was fabricated to obtain electrical output parameters of both the traditional CdTe-based cell and CdTe cell with MoO3 buffer layer. The current‒voltage measurements were carried out at room temperature under both dark and air mass 1.5 global radiations. The energy conversion efficiency value has been obtained for traditional cell and the cell with MoO3 buffer layer as 8.93% and 10.31% 1 Sun, respectively. It was observed that the integration of MoO3 layer into CdTe-based solar cell increased cell efficiency by 15.45%. [ABSTRACT FROM AUTHOR]

One of the biggest problems in industrial plants is wear that directly affects equipment life. In integrated plants such as blast furnaces, many types of wear are encountered, one of which is erosive wear. Slurry erosion is one of the effective types of erosive wear. During the transfer of the slag into the liquid medium, the transport equipment is exposed to slurry erosion. The high amount of erosion seriously shortens the life of the equipment where the transportation is carried out and increases the maintenance-repair costs. In this study, blast furnace slag was used in the slurry erosive wear test system and the abrasivity of the St 37-2 reference standard pipe material, Hardox 400 and W2C-NiCrBSi coating materials was investigated. The slag was sieved to an average particle size of 505 µm and slurry containing 10%, 20% and 30% by weight of slag was prepared. The experiments were carried out at 2 m/s and 4 m/s peripheral speed values at the partical normal impact angle (90°). It has been determined by these experimental studies that the abrasivity of the slag prepared at a certain grain size is directly related to the concentration and the rotation speed (material conveyance speed) and that the wear is also increased by increasing the concentration and rotation speed. The wear values of the materials used as specimens are determined from high to low respectively as St 37-2, Hardox 400 and W2C-NiCrBSi coating material. In addition, the morphological structures of the worn surfaces were examined using SEM(Scanning Electron Microscope) in order to understand the wear mechanisms. [ABSTRACT FROM AUTHOR]

In this study, rigid polyurethane foam composites (SPKK's) containing egg shell powder (YKT) with different ratio were synthesized. YKT was characterized by using X-ray diffactometer (XRD), X-ray fluorescence spectrometer (XRF) and Fourier transform infrared spectrophotometer (FTIR). The surface morphology, closed cell ratio and density, thermal conductivity, and compressive strength of the foams were examined/measured/determined by scanning electron microscope (SEM), gas displacement pycnometer, heat flow meter, and universal test machine, respectively. Limiting oxygen index (LOI) and cone calorimetry were used to evaluate the fire performance of the foams. The effects of YKT amount on the average cell size, closed cell ratio, thermal conductivity, density, compressive strength and fire behavior of the foams were investigated. When compared with rigid polyurethane foam without additive (SPK), while the mean cell size and thermal conductivity values of the obtained SPKKs showed a decrease, closed cell content and density values of them increased. With SPKK containing 7% YKT, the thermal conductivity was reduced by about 8%. The compressive strength values for the SPKKs at low YKT ratios were higher than that of SPK, and the strength decreased with the further increase in the amount of additives. LOI values were improved slightly with the addition of YKT. When YKT loading was %25, the LOI value of SPKK, which is %19.7 for SPK, increased to %20.4. Cone calorimetry results showed that fire performance index values of composites are better than that of SPK. [ABSTRACT FROM AUTHOR]

Shortening the processing time and increasing the efficiency have been a need in machining at all times. In addition to continuous developments in materials of cutting tools provided by the search every passing day, coating the surfaces of the existing cutting tools has been evaluated as more economical and more efficient solution. Studies deal with coating of cutting tools was started in the 1970s and coated tools were recognized as an important development in machining. Titanium carbide (TiC), titanium nitride (TiN), titanium carbonitride (TiCN), cubic boron nitride (CBN), chromium nitride (CrN) and aluminum oxide (Al2O3) are among the most widely used coating materials. Coating studies focused on especially high-speed steel and sintered carbide cutting tools as they have wide application area. In traditional coatings, are coated in the form of layers. As a result of occurring high temperatures during metal cutting, the different thermal expansions take place between the layers. Different expansions cause micro-cracks and this reduces the coating life. As a result of efforts to prevent the formation of these cracks, functional graded coatings (FGC) has been developed. In the study, high speed steel substrate material was coated as functionally graded with titanium carbonitride (TiCN) and titanium-boron carbonitride (TiBCN) coating materials. Coatings were made by magnetic sputtering method. Scanning electron microscope (SEM) images were taken and linear analyses, were realized for characterization of the coatings. [ABSTRACT FROM AUTHOR]

Strength, durability and sustainability of concrete depend on many factors. Porosity is the one of the most important factor which is affect concrete quality directly. Researchers have been using various methods to reach information relating to the porosity of cementitious systems. The most used of these methods is Mercury Intrusion Porosimetry (MIP). The last decade using of image analysis techniques have been increasing rapidly due to develop the computer technology. Pore structure, amount of void, void dimensions and porosity distribution in material can be investigated by image analysis methods. One of these techniques owing to investigate is "Computer Tomography" (CT) technique. Internal structure analysis of the cementitious systems can be performed, and voids of micron dimensions can be appeared by CT. In this study, how use the CT method to analysis of the porosity and place of CT at concrete science was explained. However, various comparisons were done between MIP and Scanning Electron Microscope to CT. [ABSTRACT FROM AUTHOR]

In this study, the morphology of the venom apparatus of species of Polistes gallicus (Linneaus,1767), Polistes nimpha (Christ,1791) and Vespula germanica (Fabricius,1793) were examined by Scanning Electron Microscope (SEM) (LEO 440) at 20 kV and compared the structure of the venom apparatus of the species. Samples were collected from different areas and brought to laboratory in appropriate circumtances. The venom apparatus (glands) of wasps and needles were removed under the stereomicroscope. Samples of tissues from the wasps were prepared to the method of electron microscopy. At the venom apparatus of Polistes gallicus (L.), it was observed that: The poison sac was in a muscular structure and round shape, the poison sting needles were curved at basal and sharply pointed, the palps were shorter than the sting, there were short dense hairs on apex of the palps. At the venom apparatus of Polistes nimpha (Christ), it was noticed that the poison sac was muscular, in an oval shape and lengthwise, the tip of poison sting was curled on apex towards ventral, the palps were shorter than the sting, the terminal of palps was covered with long and heavy feathers. At the venom apparatus of Vespula germanica (Fab.), it was found that the poison sac structure was muscular, in oval and circle shaped, the apex of the sting was stubby, the palps covered with long and fully feathers from basal to apex were longer than the sting. It is considered that morphological variation in terms of taxonomy is very important. [ABSTRACT FROM AUTHOR]

The influence of volume fraction of martensite and new ferrite on the tensile behaviour of dual-phase steel containing 0,0981% C, 1,653% Mn, 0,54% Si and 0,69% Ni has been studied. After intercritical annealing at 715, 725 and 752°C, the specimens were cooled in water, oil and furnace. The formation of carbide was not observed in the optical microscope investigation even at furnace cooling rate. The results showed that after annealing at the same intercritical temperature, the highest volume fraction of martensite was obtained by water cooling among all cooling conditions. By increasing the martensite content, both yield and tensile strengths increased while uniform elongation was decreasing. It was observed that at constant volume fraction of martensite, new ferrite content was varied by using controlled cooling from intercritical annealing temperatures. The presence of new ferrite caused a decrease in strength and increase in ductility. Scanning electron microscope investigations of fracture surface showed that the specimens with new ferrite had higher densities of microvoids in the necked region and exhibited completely ductile type of fracture. In contary, it was also observed that the specimens with no new ferrite had lower densities of microvoids and exhibited mixed type of fracture which comprises both cleavage and ductile fracture together. [ABSTRACT FROM AUTHOR]

The ceramic tile industry is being progressively moving its worldwide production toward new material with improved aesthetic and technical properties, e.g. glazed porcelain tiles that are able to successfully compete with ornamental stones and other building products. Porcelain tiles hanks to their superior properties such as whiteness, mechanical and frost resistance, low water absorption etc. attracted the attention of ceramic tile producers, causing the researches in this area to start in 80's. Today the porcelain tiles are divided into three main groups; natural, polished and glazed porcelain tiles. Porcelain tiles usually posses water absorption of less than 0.5% but in many cases it is less than 0.01%, excellent wear resistance and high breaking strength which make them high-tech products. Moreover easily cleanable and anti-slip surfaces widen their applications both in business and home residences. They can be produced in either way; glazed or unglazed, coloured with traditional stains and fired at 1200-1220 °C for 40-80 min. Porcelain tile is a highly vitrified ceramic material produced from a body formulated by mixtures of clay, quartz and sodium-potassium feldspar in which vitrification indicates a high degree of melting on firing which confers low porosity and high glass content. Feldspar minerals are essential components in igneous, metamorphic and sedimentary rocks, amongst the numerous rocks in which they are present. Feldspar minerals are essential components in igneous rocks as granite, which contains up to 50% or 70% of alkaline feldspar. Granite, however is rarely used for its feldspathic content. Rather a whole range of rocks geologically connected to granite is preferred. In this study, microgranite samples were collected from a large ceramic production region in Karaköy located in the Southeast part of Bilecik province in Turkey (NW Turkey). Due to its high alkaline (Na2O + K2O ≈ 8.0-8.5) and low Fe2O3, TiO2 content, it is likely to consider microgranite as a fluxing agent for porcelain tile bodies. The XRD pattern taken from the as-received microgranite raw material revealed the fact that the samples consisted of quartz (SiO2), albite, sanidine, muscovite and kaolinite minerals, which was supported from mineralogical point of view by DTA-TG analysis's results as well. In the first part of the experimental study, both as-received and 270 min. attrition milled microgranite samples were added into the glazed porcelain body in the following proportions 8%, 12%, 16%, 20% meanwhile albite was removed from the standard body formulation. Following the wet ball milling of standard body and studied porcelain bodies, some test samples were prepared according to standard test procedure. The prepared samples were then taken to fast firing process in roller kilns under industrial conditions of 1200 °C and 49 min. Prior to firing process slip properties of density (g/l), flow rate (s) and sieve residue (+63μ) were measured. Following this, the properties of fired body samples such as bulk density, shrinkage (%), water absorption (%), dry and fired strength and colour measurements expressed as L, a and b were measured as well. When compared with standard body, the results showed that the increase in microgranite amount decreased the water absorption and increased shrinkage and fired strength.… [ABSTRACT FROM AUTHOR]

In this research. Cyclotella comta from Bacillariophyta division (in samples which received from surroundings Tokat-Turkey) have been cultured in culture medium and investigated in scanning electron microscope (SEM). At study have been detailed C. comta in point of ultrastructurel. In analysis of micrograph have been observed that frustule has different morphological structure [ABSTRACT FROM AUTHOR]

In this study, diaza-crown ether and phosphaze-crown ethers have been investigated in scanning electron microscope (SEM) and compared to their electron micrographs. In analysis of micrograph have been observed that compounds has different morphological structure [ABSTRACT FROM AUTHOR]

In this research, Nitzschia palea from Bacillariophyta division (in samples which received from surroundings Tokat-Turkey) have been cultured in culture medium and investigated in scanning electron microscope (SEM). In analysis of micrograph have been observed that polar nodule has different morphological structure. [ABSTRACT FROM AUTHOR]

In this study, cyclic oxidation tests were conducted on C-276 Ni alloy samples both at low (T<1000 °C) and high temperatures (T>1000 °C) in stagnant air environments. After the tests, planar and cross-sectional structural features of the scales as well as the chemical compositions of the metallic and oxide regions were investigated using a scanning electron microscope equipped with a backscattered electron detector and a x-ray energy dispersive spectrometer (EDS). Results of the point, line and area EDS analyses were used to explain the oxidation behavior of the alloy. Both relatively higher weight gains and volatilization of Molybdenum (Mo) were observed for the samples oxidized at temperatures above 1000 °C. Results suggested that Mo volatilization might be responsible for the scale spallation observed for the samples oxidized at higher temperatures. [ABSTRACT FROM AUTHOR]

In this work. Alumix 431 (AI7xxx) powder was pressed cold (room temperature) and warm (80°C) and its static and dynamic mechanical properties were investigated. Experiments were performed in two stages. In the first stage, cylindrical samples (Φ15 mm, h=15 mm) were pressed warm and cold under 300-500 MPa pressure with 50 MPa intervals and sintering conditions that give optimum density were determined by sintering under three different sintering medium. In the second stage, tensile and fatigue samples that give the same density with this determined sintering condition were produced and these tests were conducted. In order to obtain the same density with cold and warm pressing in tensile and fatigue samples, 230 and 180 MPa pressure, respectively, was used. Since they have the same density, tensile and fatigue test results that were pressed cold and warm were equal. In addition, microstructures and morphologies of samples were investigated with Light and Scanning Electron Microscope. [ABSTRACT FROM AUTHOR]