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WOS: 000395150600019, Rigid polyurethane (PU) foam is used as a thermal insulating and supporting material in domestic refrigerator/freezers and it is produced by reaction injection molding (RIM) process. There is a need to improve the thermal property of rigid PU foam but this is still a challenging problem. Accordingly, this work investigates the RIM process parameters to evaluate their effects on rigid PU foam's structure and hence property. It has been found that mold temperature is a key parameter whereas curing time has negligible effect on structure of PU foam. Cell size, strut thickness, and foam density have been found very critical in controlling the thermal and mechanical properties. Upper and lower values of 30 to 32 kg/m(3) density are critical to observe contribution of radiation and solid conductivity separately. Finally, PU foam with 160 mm average cell size, 16 mm strut thickness, below 10% open cell content, and 30 to 32 kg/m(3) density allow obtaining better thermal insulation without significant reducing in the compressive strength. The presented work provides a better understanding of processing-structure-property relationship to gain knowledge on producing highquality rigid PU foams with improved properties, ARCELIK A.S,. Company; Anadolu University under Turkish Ministry of Science, Industry and Technology SANTEZ program [0053.STZ.2013-1], The authors acknowledge with appreciation the ARCELIK A.S,. Company and Anadolu University partnership under Turkish Ministry of Science, Industry and Technology SANTEZ program (0053.STZ.2013-1) for financial support. ARCELIK A.S,. Company provided suitable conditions to carry out the experiments with RIM. Thanks are also to PU Lab of ARCELIK A.S,. Company team for help with sample preparation and characterization. Throughout this work, we had many useful discussions with Murat Erdem of Anadolu University.

Ultrason., Ferroelectr. Freq. Control;(UFFC) Soc. Inst. Electr. Electron. Eng. (IEEE), 2012 21st IEEE Int. Symp. on Applications of Ferroelectrics Held with 11th IEEE European Conf. on Applications of Polar Dielectrics and 4th IEEE Int. Symp on Piezoresponse Force Microscopy and Nanoscale Phenomena in Polar Materials, ISAF/ECAPD/PFM -- 9 July 2012 through 13 July 2012 -- Aveiro -- 93333, The solid solution between bismuth ferrite and lead titanate (xBiFeO 3-(1-x)PbTiO 3 or BFPT) possesses a morphotropic phase boundary (MPB) between the rhombohedral and tetragonal forms at x=0.7. It is of interest to investigate the influence of field-driven rhombohedral-tetragonal phase transitions across the MPB, to determine whether correctly oriented BFPT can provide both giant piezoelectric properties and significant magnetoelectric coupling. Here, we used the reactive templated grain growth (RTGG) technique to prepare crystallographically textured 0.6BiFeO 3-0.4PbTiO 3 (60:40 BFPT) ceramics. Both Aurivillius structure templates (Bi 4Ti 3O 12 and PbBi 4Ti 4O 15) and perovskite templates (BaTiO 3 and SrTiO 3) were used to prepare textured 60:40BFPT. Synchrotron radiation experiments were used to determine the degree of texture. A current data suggests that only BaTiO 3 templates survive the sintering process, and other candidate template materials reacted with the 60:40BFPT matrix at high temperature. In the case of SrTiO 3, this reaction results in a low Curie temperature (T c = 350 °C) due to the substitution of Sr 2+. Aurivillius templates resulted in high Curie temperatures (610 °C) and may be chemically suitable if they could be stabilized during the sintering process. However, the resulting ceramics show low remanent polarization (P r = 3 µc/cm 2), while SrTiO 3 and BaTiO 3 templated ceramics show higher remanent polarizations of 36 and 30 µc/cm 2, respectively. Because of their high chemical stability in this system, BaTiO 3 templates appear to be the best candidate for fabricating textured BFPT by the TGG method, displaying a high degree of crystallographic texture.

36th FEBS Congress of the Biochemistry for Tomorrows Medicine -- JUN 25-30, 2011 -- Torino, ITALY, WOS: 000292333102459, …, Federat Soc Biochem & Mol Biol

10th International Conference and Exhibition of the European-Ceramic-Society -- JUN 19, 2007 -- Berlin, GERMANY, WOS: 000283987400041, Homogeneous precipitation of hydroxides was investigated as an alternative method to synthesize Fe-doped aluminum oxide (alpha-Al2-2xFe2xO3) particles over which carbon nanotubes (CNTs) were grown via a catalytic chemical vapor deposition (CCVD) method. Performance of the homogeneously precipitated particles for CNT growth was quantitatively compared with that of the combustion-synthesized particles. The main advantage of the homogeneous precipitation of hydroxides and subsequent calcination process against to the combustion synthesis and other commonly practiced chemical routes is the ability to tailor the Fe-doped Al2O3 precursor powder characteristics such as size and specific surface area (SSA) without requiring any milling step and also to control the phase composition of the oxide powder with high Fe content, and subsequently the quality and quantity of CNTs during CCVD process. The particle size of the precipitated and calcined alpha-Al2-2xFe2xO3 powders varies between similar to 50 and 400 nm for 5-10 cat.% Fe-containing systems. The monodispersed particle size distribution and optimum phase composition of the homogeneously precipitated powders, particularly for a 10 cat.% Fe content in the starting oxide, and their much higher SSA than similar materials prepared by other chemical routes lead to production of high amounts of good quality CNTs., European Ceram Soc

Scientific and Technological Research Council of Turkey, 5th International Symposium on Nitrides -- 3 April 2006 through 5 April 2006 -- Eskisehir -- 71251, In this study, textured ?-SiAlON ceramic was produced by templated grain growth process. In order to enhance the alignment of the seeds, gated tape casting arrangement was utilized. Y-Ce codoped seeds were synthesized to induce the preferred orientation. For the production of the seeds, Ce3+ was used as a sintering additive due to its well-known effect on the formation of elongated ?-SiAlON grains. In addition, Y3+ was used to stabilize Ce3+ in ?-SiAlON structure. Gated tape casting arrangement was also used to enhance the alignment of the seeds in the green tape. After the lamination and sintering, preferentially aligned ?-SiAlON grains were observed by the microstructural investigation. In addition, XRD results obtained from the planes parallel and perpendicular to the casting direction indicated the alignment of grains in ?-SiAlON ceramics. Hardness measurements also confirmed that the alignment of the grains results in 8% increase in hardness value of the plane perpendicular to the casting direction with respect to that of the parallel one.

8th Conference of the European-Ceramic-Society -- JUN 29-JUL 03, 2003 -- Istanbul, TURKEY, WOS: 000223059700285, Synthesis of nanosized SnO2 ceramic particles via homogeneous precipitation was investigated as a function of processing parameters such as initial concentration and calcination temperature. Hydrous tin oxide was precipitated from 0.01-1 M SnCl4-urea aqueous solutions by decomposition of urea at similar to90degreesC. SnO2 particles with a specific surface area as high as 25.3 m(2)/g were synthesized. The crystallite size of tin oxide increased with increasing initial concentration. Calcinations resulted in crystal growth and agglomeration and subsequently, reduction in the effective surface area of tin oxide powders., Turkish Ceram Soc, European Ceram Soc

21st IEEE ISAF, held Jointly with 11th ECAPD and 4th Conference on PFM and Nanoscale Phenomena in Polar Materials -- JUL 09-13, 2012 -- Univ Aveiro, Aveiro, PORTUGAL, WOS: 000313016400097, The solid solution between bismuth ferrite and lead titanate (xBiFeO(3)-(1-x)PbTiO3 or BFPT) possesses a morphotropic phase boundary (MPB) between the rhombohedral and tetragonal forms at x=0.7. It is of interest to investigate the influence of field-driven rhombohedral-tetragonal phase transitions across the MPB, to determine whether correctly oriented BFPT can provide both giant piezoelectric properties and significant magnetoelectric coupling. Here, we used the reactive templated grain growth (RTGG) technique to prepare crystallographically textured 0.6BiFeO(3)-0.4PbTiO(3) (60: 40 BFPT) ceramics. Both Aurivillius structure templates (Bi4Ti3O12 and PbBi4Ti4O15) and perovskite templates (BaTiO3 and SrTiO3) were used to prepare textured 60:40BFPT. Synchrotron radiation experiments were used to determine the degree of texture. A current data suggests that only BaTiO3 templates survive the sintering process, and other candidate template materials reacted with the 60: 40BFPT matrix at high temperature. In the case of SrTiO3, this reaction results in a low Curie temperature (T-c = 350 degrees C) due to the substitution of Sr2+. Aurivillius templates resulted in high Curie temperatures (610 degrees C) and may be chemically suitable if they could be stabilized during the sintering process. However, the resulting ceramics show low remanent polarization (P-r = 3 mu c/cm(2)), while SrTiO3 and BaTiO3 templated ceramics show higher remanent polarizations of 36 and 30 mu c/cm(2), respectively. Because of their high chemical stability in this system, BaTiO3 templates appear to be the best candidate for fabricating textured BFPT by the TGG method, displaying a high degree of crystallographic texture., IEEE, IEEE, Ultrason, Ferroelect & Frequency Control (UFFC) Soc

2nd International Conference on Electrophoretic Deposition -- MAY 29-JUN 02, 2005 -- Castelvecchio Pascoli, ITALY, WOS: 000238128200022, Electrophoretic deposition technique is a versatile coating method. With this method not only flat surfaces but also curved or rough surfaces can be coated in various thicknesses. In this study, BaTiO3 nanocrystals were synthesized with a novel nonaqueous method. In a simple one pot reaction process, the metallic barium is directly dissolved in benzyl alcohol at slightly elevated temperatures. After the addition of titanium isopropoxide and subsequent solvothermal treatment nearly spherical BaTiO3 nanocrystals typically 5 nm in diameter were obtained. The stability of the suspension in ethanol and nanocrystalline particle size distribution was measured by Malvern Nano-ZS. The BaTiO3 suspensions were directly used in an electrophoretic deposition process without any additional operation. Pt plated alumina was used as substrate. Various voltages were applied by altering the cathode to anode distance as well as deposition time for optimal process control. Because of the ethanol adsorbed on the surface of the nanoparticles, application of high voltages was possible without causing hydrolysis. The deposited surface coatings were dried in air atmosphere and sintered at different temperatures. SEM, EDX and XRD analysis were employed for the investigation of the coating., Engn Conf Int, Electrochem Soc, Amer Ceram Soc, European Ceram Soc, Inst Mat Minerals & Min, London, German Mat Soc

Küfler, çeşitli hava hareketleri ile iç ortamlara sporlarını kolaylıkla taşıyabilirler ve gerekli ortam şartları sağlandığında taşındıkları ortamda hızlı bir şekilde çoğalarak yayılış gösterir. Küflere ait olan sporların etrafa yayılması ile de çeşitli ikincil hastalıkların oluşması için uygun ortam sağlanmış olur. Özellikle hastane, okul, toplu taşıma alanları gibi halka açık yerlerde kişiden kişiye de hastalıkların bulaşmasını kolaylaştırır. Söz konusu mikroorganizma grubunun, iç ortam havasındaki sayısının azaltılması ve daha temiz bir ortam oluşturulması için çeşitli biyomalzemelerin, biyoplastiklerin, boyaların, metal ve cam araç-gereçlerin yapımı artmış durumdadır. Bu çalışmada çinko oksit ve/veya gümüş ile zenginleştirilmiş formlarından oluşan 10 adet özel tasarlanmış nanopartikülün, Türkiye'nin 5 farklı yenidoğan ünitesi iç havasından elde edilmiş olan toplam 39 farklı küf türüne karşı antifungal aktivitesi incelenmiştir. Kuyucuk testi, agar dilüsyon testi, minimum inhibe edici konsantrasyonun belirlenmesi yöntemleri kullanılarak antifungal aktivite incelenmiştir ve etkin dozların etki mekanizmalarının belirlenmesi üzerine uygulama gerçekleştirilmiştir. Sonuç olarak, incelenen nanopartiküllerin test mikroorganizmaları üzerinde farklı seviyelerde antifungal etki özelliğine sahip oldukları ve bu etkinin gümüş katkısı ile değişken sonuçlar sergilediği belirlenmiştir.Anahtar Sözcükler: Çinko oksit, Gümüş, İç hava, Küf, Nanopartikül Microfungi can easily carry their spores to indoor environments thanks to various air movements. The microorganisms in question rapidly proliferate and spread in the environment where they are transported when the necessary environmental conditions are provided. As the spores of the microfungi spread out, a suitable environment paves the way for the arising of various secondary diseases. Especially in public places such as hospitals, schools and public transportation areas, it makes the transmission of diseases from person to person easier. The production of various biomaterials, bioplastics, paints, metal and glass equipment has been increased to reduce the number of this microorganism group in indoor air and to create a cleaner environment. In this study, the antifungal activity of 10 different specially designed nanoparticles based from zinc oxide and enriched with silver against was performed against to 39 different microfungus species isolated from indoor air of 5different newborn units of Turkey. The antifungal activity was investigated by using agar well diffusion, agar dilution, and minimum inhibitory concentration methods and focused on determination of activity mechanisms of effective doses. As a result, we exhibited that test nanoparticles have antifungal activity on different levels and silver doped forms showed variable effects.Key words: Zinc oxide, Silver, Airborne, Microfungi, Nanoparticle 65

Ülkemizin önemli ihracat kalemlerinden birisi olan seramik sağlık gereçleri sektörü, 2018 yılı verilerine göre 210,1 milyon $'lık ihracat hacmiyle yerli üretimin ekonomiye olan katma değerini ortaya koymaktadır. Evimizde mutfakta, banyoda ve tuvalette kullandığımız lavabo, hela taşı, klozet gibi seramik sağlık gereçleri sektörü ürünleri ile okullar, iş yerleri, alış-veriş merkezleri gibi ortak kullanım alanlarında da etkileşim içinde oluruz. Genellikle beyaz renkte olan bu ürünler estetik açıdan parlak ve düzgün yüzeylere sahip olması, ürünlerin kolay temizlenebilir olması ve aynı zamanda da gerekli hijyen koşullarını yerine getirebilmeleri için sırlama işlemine tabii tutulurlar. Seramik sağlık gereçleri ürünlerinin sırlarından beklenen bu özelliklerin sağlanabilmesi için sır reçetelerine farklı katkı malzemeleri eklenmektedir. Fakat, bu yardımcı ajan malzemelerin sır reçetesi ile uyumsuzluğu iğne deliği, çatlama, pullanma, toplanma, matlaşma ve lekelenme gibi hatalara neden olabilmektedir. Çinko oksit, sır reçetesi içerisinde ergime sıcaklığını düşürmektedir aynı zamanda sırın yüzey özelliklerini de olumlu yönde etkilemektedir. Bu tez çalışmasında da standart seramik sağlık gereçleri sır reçetesine ağırlıkça farklı oranlarda tasarlanmış çinko oksit esaslı partiküller eklenerek, seramik sağlık gereçleri sırlarında kullanılabilirliği incelenmiştir. Tasarlanmış çinko oksit esaslı partiküllerin eklendiği sır reçetelerinin ısıl genleşme katsayıları, sinterleme ve ergime sıcaklıkları analiz edilerek sır-bünye uyumu değerlendirilmiştir. Ayrıca son üründeki pürüzlülük ve renk ölçümleri de tamamlanarak tasarlanmış çinko oksit esaslı partiküllerin ürünlerin yüzey özelliklerine olan etkisi incelenmiştir. Yapılan bu çalışmada tasarlanmış çinko oksit esaslı partiküllerin seramik sağlık gereçleri sırlarında kullanılabilir olduğu sonucuna varılmıştır. Ceramic sanitaryware sector, which is one of the important export components of our country, shows the added value of domestic production to the economy with its export volume of $210,1 million according to 2018 data. We interact with ceramic sanitary ware products, such as sinks, squatting pans, toilets which we use in the kitchen, bathroom and toilet, and in common areas such as schools, workplaces and shopping centers. These products, which are usually in white color, are subjected to glazing in order to have aesthetically bright and smooth surfaces, to be easy to clean the products and to fulfill the necessary hygiene conditions. Different additives are added to glaze recipes in order to provide these properties expected from the glazes of ceramic sanitaryware products. However, incompatibility of these agent materials with the glaze recipe can cause errors such as pinhole, cracking, peeling, crawling, dulling and staining. Zinc oxide reduces the melting temperature in the glaze recipe and has a positive effect on the surface properties of the glaze. In this thesis, designed zinc oxide based particles in different proportions by weight were added to the standard ceramic sanitaryware glaze recipe and its usability in ceramic sanitaryware glazes was investigated. Thermal expansion coefficients, sintering and melting temperatures of glaze recipes in which designed zinc oxide based particles were added were analyzed and glaze-body compatibility was evaluated. In addition, the roughness and color measurements of the final product have been completed and the effect of the designed zinc oxide based particles on the surface properties of the products has been examined. In this study, it is concluded that designed zinc oxide based particles can be used in ceramic sanitary ware glazes. 72