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Çalışmanın amacı, seramik bünyeler üzerine uygulamak üzere şeffaf sırların bor türevi atığının katkılanması ile daha ekonomik ve çevreci bir yöntem ile üretimidir. Bor türevi atığı katkılı şeffaf seramik sırları üretilmiş ve bu sırlar üretilen seramik bünyeler üzerine fritleme yapılmadan doğrudan uygulanmıştır. Değişken pişirme sıcaklığı (950 ºC-1150 ºC) ve atık katkı oranına (0-15 %ağ.) bağlı olarak XRD ve spektrofotometre kullanılarak sırların faz gelişimleri ve optik özellikleri incelenmiştir. 950 ºC’de üretilen sırlarda görülen adacık kusuru ve iğne deliği yüzey hataları 1150 ºC’de tüm sırların yapısının tamamen amorflaşması ile giderilmiştir ve atık katkılı sırların parlaklık değerleri artmıştır. Düşük sıcaklıklarda atık miktarı ile artan diopsit fazı parlaklık (60º) değerlerinde azalmaya ve beyazlık (L*) değerlerinde artışa sebep olmuştur. Özetle, 1150 ºC’de pişirim yapıldığında %5 atık katkılı sırın parlaklık ve beyazlık değerleri (56,6 ve 87,7) katkısız sıra (49,4 ve 85,3) kıyasla daha yüksektir. Üretilen düşük maliyetli ve çevre dostu bor atığı katkılı sırlar sanatsal seramik çalışmalarında kullanılabilir.

In this study, the effect of seashell utilization as a replacement for calcite on the surface features and optical properties of white ceramic glazes was investigated. As received seashells collected from Black Sea beaches of Samsun, Turkey and purified seashells at 700°C for 1 h were used as calcite replacement by 15 wt.%. Seashell powders were incorporated to white glaze compositions which are applied on the surface of different fired clay bodies such as red clay, chamotte, white and porcelain by dipping technique. Next, the glazed green bodies were sintered at 1100ºC for 8 h. Following to TG-DTA, heating microscope, XRD and optical analysis, the obtained results exhibited that as received seashell powder (SP-1) was composed of calcite (CaCO3), whereas purified seashell powder (SP-2) comprised aragonite (CaCO3) and calcium oxide (CaO). The iron (hematite) content in red clay and the impurities in seashells composition caused specks and crawlings on the surface of glazed red clay bodies and of some glazes containing seashell, respectively. In generally, the higher CaO content in SP-2 enhanced gloss (60°) values, and whiteness values of most glazed surfaces were closed to each other. The color of chamotte bodies increased redness-greenness values. The variations in optical parameters were mainly associated with the difference in body compositions. SP-1 contained glaze, applied on porcelain body, was selected as optimal because that had 33 gloss value, high whiteness (87) and no surface defect. Therefore, the utilization of as received seashells by 15 wt.% as calcite replacement allows eco-friendly and cost-effective production of white ceramic glazes without any additional heat treatment.

Seramik bünyeyi ince bir tabaka halinde kaplayan ve camsı yapı oluşturan sırlar, seramik yapıya koruyucu tabaka sağlaması ile birlikte sırın kimyasal bileşimine ve pişirim parametrelerine bağlı ürünün renk, parlaklık ve yüzey pürüzlülüğü gibi özelliklerini etkilemektedir. Seramik sırları için renk önemli bir faktördür. Sırların renklendirilmesi için pigmentlerden, metal oksitlerden veya doğal hammadde kaynaklarından yararlanılmaktadır. Günümüzde seramik teknolojisinin gelişimiyle birlikte doğal kaynak ve atık malzemelerin seramik ve seramik sır hammaddesi olarak kullanımı artmakta ve ticari sır üretiminin yanı sıra doğadan temin edilen malzemelerle alternatif sır kompozisyonları oluşturulmaktadır. Bu çalışmada Samsun ili Terme ilçesinde bulunan Simenit Gölü kıyısından temin edilen kumun şeffaf sır kompozisyonunda yeni bir renklendirici kaynağı olarak kullanımı araştırılmıştır. Simenit Gölü Kumu (SGK) öğütme işleminin ardından faz analizi için XRD ve kimyasal kompozisyonunun belirlenmesi için XRF analizlerine tabi tutulmuştur. Termal davranışlarının belirlenmesi için ısı mikroskobu ve TG/DTA analizleri gerçekleştirilen SGK farklı oranlarda şeffaf sır kompozisyonlarına ilave edilmiş ve seramik bünyelere uygulanmıştır. Farklı oranlarda SGK katkısı ile hazırlanan sırlı bünyelerin pişirimi sonrasında renk analizleri gerçekleştirilmiş ve sarıdan kızıl kahveye renk geçişi gözlemlenmiştir.

KOROGLU, LEVENT/0000-0003-4696-1459 WOS: 000524268500001 In this study, the investigation of the optical properties and microstructural development of matte glaze compositions prepared with the addition of seashells was aimed. The seashells obtained from Black Sea beaches of Samsun, Turkey were characterized using XRF, XRD, FTIR, TG-DTA techniques, and heating microscope. The calcite-aragonite polymorphic transition was provided by heat treatment of seashell powders at 700 degrees C for 1 hour and then, aragonite-based seashell powders were incorporated to matte glaze compositions up to 30 wt%. Firstly, four different types of fired body specimens (red clay, chamotte, white, and porcelain) were produced at 800oC for 7 hour. Secondly, the prepared glazes were applied on surface of all fired bodies and then, all bodies were sintered at 1100oC for 8 hour. Finally, coloring parameters and microstructural features of seashell added glazes were determined. The addition of seashells to glaze composition by 10 and 20 wt% resulted in higher transparency. The matte glaze was formed with increment of seashell content to 30 wt%. The more reduced fluidity of the glaze caused nonhomogenous matte appearance. As a result, it is possible to produce transparent glazes in eco-friendly and cost-effective way by addition of seashells into glaze composition in 20 wt%. 2209-A Scientific Research Project of The Scientific and Technological Research Council of Turkey (TUBITAK)Turkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK) [1919B011802514] This work was supported by 2209-A Scientific Research Project of The Scientific and Technological Research Council of Turkey (TUBITAK) [1919B011802514].

Tam Metin / Full Text Kemik doku iskelelerinin tasarımı gelişen teknoloji ve üretim metodları ile değişmekte ve gelişmektedir. Tasarım ihtiyaçlarından bir tanesi olan dejeneratif hastalıklar sonucu ortaya çıkan osteoporoz nedeni ile kemik dokusu deformasyonu ve kaybı gibi kemik patolojileri, yaşamın kalitesini ve yaşam standartlarını olumsuz etkilemektedir. Bu nedenle kemik rejenerasyonu için üç boyutlu biyoaktif kemik doku iskelelerinin geliştirilmesi, doku mühendisliği alanında büyük önem kazanmıştır. Kemik doku yapısının başarılı bir biçimde taklit edilebilmesinde kemik doku mühendisliği uygulamaları için tasarlanan biyomalzemelerde polimerler ve biyoaktif seramikler kullanılmaktadırlar. Hidroksiapatit (HA) ve biyoaktif camlar ile üretilmiş kemik doku iskeleleri yüksek biyouyumluluğa ve kemik dokusuna bağlanma özelliğine sahip olduğundan dolayı kemik rejenerasyonu için klinik potansiyele sahiptir. Ancak kemik dokusuna benzer gözenekli olarak tasarlanan HA ve biyoaktif cam kemik doku iskelelerin mekanik özellikleri özellikle yük taşıyan uygulamalar için uygun değildir. Mekanik özellikleri iyileştirmek amacıyla seramik, metal, polimer ve cam gibi ikincil fazların ilavesiyle HA bazlı kompozitler üretilmektedir. Kemik iskelesi üretiminde baskı prensipleri ve malzeme seçimine göre stereolitografi, toz tabakalı füzyon, malzeme ekstrüzyonu, binder jetleme ve üç boyutlu (3B) yazıcı ile şekillendirme gibi çeşitli yöntemler uygulanmaktadır. Geleneksel yöntemler; gözenek boyutu, geometrisi ve birbirine bağlılığı üzerinde sınırlı kontrol imkânı sunmaktadır. Ancak 3B yazıcı teknolojileri geliştikçe, kemik mikro mimarisini kontrol edilebilme becerisinde ilerlemeler kaydedilmiştir. The design of the bone scaffolds changes and develops with the developing technology and production methods. Degenerative diseases which are one of the design needs like osteoporosis, result in bone pathologies such as, degeneration and loss of bone tissue, adversely affecting quality of life and living standards. Therefore, the development of three-dimensional bioactive bone tissue scaffolds for bone regeneration come into prominence in tissue engineering. Polymers and bioactive ceramics are used as biomaterials designed for bone tissue engineering applications that bone tissue structure can be successfully imitated. Bone tissue scaffolds produced with hydroxyapatite (HA) and bioactive glasses have a clinical potential for bone regeneration due to their high biocompatibility and binding properties to bone tissue. However, the mechanical properties of HA and bioactive glass bone tissue scaffolds, which are designed to be porous like bone tissue, are not particularly suitable for load bearing applications. HA based composites are produced by adding secondary phases such as ceramic, metal, polymer, and glass to improve the mechanical properties. A variety of manufacturing methods such as stereolithography, powder layered fusion material extrusion, binder jetting and three-dimensional (3D) printing are applied to fabricate bone tissue scaffolds according to the printing principles and selection of materials. Conventional methods offer limited control over pore size, geometry, and interdependence for this production. However, 3D printing technologies have evolved, progress has been recorded in the ability to control bone micro-architecture

The effect of particle size and phosphorous content in biomineralization media on in vitro bioactivity of monticellite based ceramic powders was investigated. Monticellite based ceramic powder was synthesized at 800 °C for 4 h using boron derivative waste. Monticellite based ceramic powder, comprising monticellite, akermanite, diopside, calcium magnesium borate and zeolite LTA crystalline phases, was crushed and then ball-milled for optimized time to obtain lowest average particle size and the narrowest particle size distribution. In vitro bioactivity of both coarse (d10: 0.5 μm, d50: 3.0 μm, d90: 42 μm) and fine (d10: 0.5 μm, d50: 1.4 μm, d90: 4.8 μm) wafers was determined by incubation in Lactated Ringer's Solution and Human Blood Plasma for 1, 3, 5, 7, 14, 21 and 28 days at 36.5 ± 0.5 °C. The obtained results exhibited that calcite (CaCO3) layer after immersion in Lactated Ringer's Solution and bone-like apatite layer after immersion in Human Blood Plasma were formed on the surface of coarse and fine wafers. The presence of phosphorus in biomineralization media is necessary for apatite formation. The increment of surface roughness favors homogeneous nucleation, and fasten nucleation and growth kinetics of precipitation. As a result, the bioactive characteristic of monticellite based ceramic powder could be governed by the particle size. Resumen: Se investigó el efecto del tamaño de partícula y el contenido de fósforo en los medios de biomineralización sobre la bioactividad in vitro de polvos cerámicos a base de monticellita. El polvo cerámico a base de monticellita se sintetizó a 800 °C durante 4 h utilizando residuos de derivados de boro. El polvo cerámico a base de monticellita, que comprende monticellita, akermanita, diópsido, borato de calcio y magnesio y fases cristalinas de zeolita LTA se trituró, y luego se molió con bola durante un tiempo optimizado para obtener el tamaño de partícula promedio más bajo y la distribución de tamaño de partícula más estrecha. La bioactividad in vitro de obleas gruesas (d10: 0.5 μm, d50: 3.0 μm, d90: 42 μm) y finas (d10: 0.5 μm, d50: 1.4 μm, d90: 4.8 μm) se determinó mediante incubación en solución de Ringer lactato y plasma sanguíneo humano durante 1, 3, 5, 7, 14, 21 y 28 días a 36,5 ± 0,5 °C. Los resultados obtenidos mostraron que la capa de calcita (CaCO3) después de la inmersión en la solución de Ringer lactato y la capa de apatita similar a un hueso después de la inmersión en plasma sanguíneo humano se formaron en la superficie de obleas gruesas y finas. La presencia de fósforo en los medios de biomineralización es necesaria para la formación de apatita. El incremento de la rugosidad de la superficie favorece la nucleación homogénea y fija la cinética de nucleación y crecimiento de la precipitación. Como resultado, la característica bioactiva del polvo cerámico a base de monticellita podría estar gobernada por el tamaño de partícula.

WOS: 000370283300006, PubMed ID: 26589596, Background: Despite improvement in operative techniques and antibiotic therapy, septic complications still occur in open fractures. We developed silver ion containing ceramic nano powder for implant coating to provide not only biocompatibility but also antibacterial activity to the orthopaedic implants. Questions/ purposes: We hypothesised silver ion doped calcium phosphate based ceramic nano-powder coated titanium nails may prevents bacterial colonisation and infection in open fractures as compared with uncoated nails. Methods: 33 rabbits divided into three groups. In the first group uncoated, in the second group hydroxyapatite coated, and in the third group silver doped hydroxyapatite coated titanium nails were inserted left femurs of animals from knee regions with retrograde fashion. Before implantation of nails 50 mu l solution containing 10(6) CFU/ml methicillin resistance Staphylococcus aureus (MRSA) injected intramedullary canal. Rabbits were monitored for 10 weeks. Blood was taken from rabbits before surgery and on 2nd, 6th and 10th weeks. Blood was analysed for biochemical parameters, blood count, C-reactive protein and silver levels. At the end of the 10 weeks animals were sacrificed and rods were extracted in a sterile fashion. Swab cultures were taken from intramedullary canal. Bacteria on titanium rods were counted. Liver, heart, spleen, kidney and central nervous tissues samples were taken for determining silver levels. Histopathological evaluation of bone surrounding implants was also performed. Results: No significant difference was detected between the groups from hematologic, biochemical, and toxicological aspect. Microbiological results showed that less bacterial growth was detected with the use of silver doped ceramic coated implants compared to the other two groups (p = 0.003). Accumulation of silver was not detected. No cellular inflammation was observed around the silver coated prostheses. No toxic effect of silver on bone cells was seen. Conclusion: Silver ion doped calcium phosphate based ceramic nano powder coating to orthopaedic implants may prevents bacterial colonisation and infection in open fractures compared with those for implants without any coating

WOS: 000360215600025, PubMed ID: 26306474, In this study, the antibacterial, cytotoxic, and angiogenic activities of silver doped calcium phosphate-based inorganic powder (ABT or PAG) were systematically investigated. ABT powders containing varying silver content were fabricated using a wet chemical manufacturing method. Antibacterial efficiencies of the ABT powders were investigated using a standard test with indicator bacteria and yeast. The cytotoxic effects of ABT on three different fibroblast cells and human umbilical vein endothelial cells (HUVECs) were assessed using MTT assay. ABT powder exhibits concentration-related cytotoxicity characteristics. Apoptotic activity, attachment capability, and wound healing effects were examined on fibroblasts. The angiogenic activity of ABT was investigated by tube formation assay in HUVECs; 10 mu g ml(-1) and 100 mu g ml(-1) concentrations of the highest metal ion content of ABT did not disrupt the tube formation of HUVECs. All these tests showed that ABT does not compromise the survival of the cells and might impose regeneration ability to various cell types. These results indicate that silver doped calcium phosphate-based inorganic powder with an optimal silver content has good potential for developing new biomaterials for implant applications., Anadolu University, Commission of Scientific Research Projects [050210, 080246]; Scientific and Technological Research Council of Turkey [TUBITAK-108M177]; Republic of Turkey-Ministry of Industry [SAN-TEZ 0086.STZ.2007-1], The authors are grateful to Anadolu University, Commission of Scientific Research Projects (Projects 050210 and 080246), Scientific and Technological Research Council of Turkey (TUBITAK-108M177), Republic of Turkey-Ministry of Industry (SAN-TEZ 0086.STZ.2007-1) for financial support. The authors also sincerely thank Caitrin Crudden (Karolinska Institute, Department of Oncology-Pathology, Cancer Center Karolinska) for proofreading of manuscript.