An Investigation on Potential Use of Ice Thermal Energy Storage System as Energy Source for Heat Pumps

It has been crystalclear to everyone that ice storage systems provide significant advantages inreducing cooling costs, balancing energy supply and demand profiles, andshaving peak loads. As the main purpose of ice storage systems is for coolingpurposes, separate heating systems, such as furnaces, heat pumps, electricalheaters, etc., are required for buildings with heating demands. This workoffers to use an ice storage system in the heat pump as the energy source.Comprehensive thermodynamic and economic analyses are conducted to assess theproposed system. The proposed system is implemented in an office building inIstanbul, Turkey. Thermodynamic studies indicate that while the overallenergetic and exergetic coefficient of performance (COP) values for the icestorage integrated air conditioning (AC) are calculated to be 4.57 and 2.04,respectively, they are 3.99 and 2.12 for the ice storage integrated heat pump.While the yearly operating cost for the traditional AC is 1.9 million TL, it is0.5 million for the ice storage integrated AC. The annual natural gasconsumption cost for heating is 295,000 TL, and 375,000 TL for the ice storageintegrated heat pump. The payback period of the ice storage integrated AC andheat pump system is observed to be 4.5 years. It may provide almost 8 millionTL savings at the end of 10 years. At the end of the present study, it isreached that the ice storage system has a promising potential to use in heatpumps as a low-temperature energy source. Also, it provides a moreenvironmentally friendly heating operation as it does not require fossil fuelsby removing the furnaces or provides higher COP for heat pumps.&nbsp; &nbsp;&nbsp;</p

Pedodonti Hastalarinin Ebeveynlerinin Periodontal Sağliğa Ilişkin Bilgi Ve Tutumlarinin Değerlendirilmesi

Aim: Family is the most important environment wherechildren acquire knowledge, attitudes, and habitsrelated to oral health. The aim of this study was toevaluate the knowledge and attitudes of parentstoward periodontal health and diseases, and therelationship of their knowledge and attitudes withdemographic data.Materials and Methods: 500 parents, referred forthe treatment of their children were included in thestudy. The knowledge and attitudes of the parentswere assessed using a self-administered and structuredquestionnaire. Data were analyzed by chi-squaretest, with the level of significance set at p0.05.Results: 33.0% parents and 33.6% children brushedtheir teeth twice or more daily. 17% parents and 8.6%children used dental floss/interdental brush, and 77%parents visited a dentist only when they experienceddental complaints. Most parents incorrectly definedthe meaning of dental plaque and did not know itsrole in the etiology of gingival diseases. 47.4% ofthem were aware that bleeding gums indicated thepresence of periodontal disease, while only 11.8%knew that one of the main reasons of tooth loss wasperiodontal disease. It was also evident that the useof dental floss significantly increased with an increasein income level (p0.05), and the knowledge andattitude of the parents regarding periodontal healthsignificantly increased with the educational level(p0.05).Conclusion: The knowledge and attitude of theparents regarding periodontal health were poor. Thus,an improvement in the knowledge and awarenessamong the parents can prevent or reduce the severityof possible periodontal problems in their children.Amaç: Aile, çocukların ağız sağlığı ile ilgili alışkanlık,bilgi ve tutumlarında etkisi olan en önemli ortamdır. Buçalışmanın amacı, ebeveynlerin periodontal sağlık vehastalığa yönelik bilgi ve tutumlarını değerlendirmekve bilgi ve tutumlarının demografik verilerle ilişkisiniaraştırmaktı.Gereç ve Yöntem: Çocuklarının tedavisi için başvuran500 ebeveyn çalışmaya dahil edilmiştir.Ebeveynlerin bilgi ve tutumları, yapılandırılmış biranket kullanılarak değerlendirilmiştir. Veriler ki-karetesti ile analiz edilmiş, anlamlılık düzeyi p0.05 olarakbelirlenmiştir.Bulgular: Ebeveynlerin %33.0?ı ve çocukların %33.6?sı dişlerini günde iki veya daha fazla fırçalamaktadır.Ebeveynlerin %17?si ve çocukların %8.6?sıdiş ipi/arayüz fırçası kullandığını ve %77'si dental şikayetleribulunması durumunda diş hekimini ziyaret ettiğinibelirtmiştir. Ebeveynlerin çoğunluğu dental plağıyanlış tanımlamış ve diş eti hastalıklarının etiyolojisindeki rolüne doğru cevap vermemiştir. %47.4'üdişeti kanamasının periodontal hastalığı işaret ettiğinive %11.8'i diş kaybının ana nedenlerinden birinin deperiodontal hastalık olduğunu bildiğini belirtmiştir.Ayrıca diş ipi kullanımının gelir düzeyi arttıkça anlamlışekilde arttığı (p0.05) ve ebeveynlerin periodontalsağlık konusundaki bilgi ve tutumlarının eğitim düzeyiile anlamlı olarak arttığı da gözlenmiştir (p0.05).Sonuç: Ebeveynlerin periodontal sağlık konusundakibilgi ve tutumu zayıf bulunmuştur. Bu nedenle,ebeveynlerin bilgi ve farkındalıklarında bir gelişme,çocuklarında olası birçok periodontal sorununciddiyetini önleyebilir veya azaltabilir

Türkiye'de kurulan ilk pişmaniye imalathanesi ; İpek Pişmaniye

Ankara : İhsan Doğramacı Bilkent Üniversitesi İktisadi, İdari ve Sosyal Bilimler Fakültesi, Tarih Bölümü, 2013.This work is a student project of the The Department of History, Faculty of Economics, Administrative and Social Sciences, İhsan Doğramacı Bilkent University.by Ayşegül Avcı.Avcı, Ayşegül. HIST 200-19AVCI HIST 200-19/9 2012-1

Mechanical and Biocompatibility Properties of Calcium Phosphate Bioceramics Derived from Salmon Fish Bone Wastes.

Natural calcium phosphates derived from fish wastes are a promising material for biomedical application. However, their sintered ceramics are not fully characterized in terms of mechanical and biological properties. In this study, natural calcium phosphate was synthesized through a thermal calcination process from salmon fish bone wastes. The salmon-derived calcium phosphates (sCaP) were sintered at different temperatures to obtain natural calcium phosphate bioceramics and then were investigated in terms of their microstructure, mechanical properties and biocompatibility. In particular, this work is concerned with the effects of grain size on the relative density and microhardness of the sCaP bioceramics. Ca/P ratio of the sintered sCaP ranged from 1.73 to 1.52 when the sintering temperature was raised from 1000 to 1300 degrees C. The crystal phase of all the sCaP bioceramics obtained was biphasic and composed of hydroxyapatite (HA) and tricalcium phosphate (TCP). The density and microhardness of the sCaP bioceramics increased in the temperature interval 1000-1100 degrees C, while at temperatures higher than 1100 degrees C, these properties were not significantly altered. The highest compressive strength of 116 MPa was recorded for the samples sintered at 1100 degrees C. In vitro biocompatibility was also examined in the behavior of osteosarcoma (Saos-2) cells, indicating that the sCaP bioceramics had no cytotoxicity effect. Salmon-derived biphasic calcium phosphates (BCP) have the potential to contribute to the development of bone substituted materials