Investigation of wear strength of blast furnace slag blended polymer materials

Having symmetrical and balanced material properties, polymer matrix composites are increasingly becoming popular due to easiness of construction and are use in the production of aerospace and automotive structures. In the study, we developed polymer composites based on epoxy resins, containing up to 40 wt.% of blast furnace slag and determined their pin-on-disc dynamic friction, wear, Shore hardness and surface roughness values. Wear tests were performed using a pin-on-disc under dry friction conditions, at the loads of 5, 10, 15 and 30 N, using slip velocity of 0.3 m/s and along distance of 500 m. The hardness and wear resistance values increased with the increase in the content of blast furnace slag. Showing the relationship between wear rate and hardness, an equation with parameters dependent on load was provided. There was an increase in the dynamic friction with an increase in the surface roughness. In addition, dynamic friction was an increasing function of the wear rate. The wear surfaces of the polymer composites were analyzed using scanning electron microscopy. It was observed that the wear rate of the epoxy composites and pure epoxy samples ranged from 19.85 to 171.42 mm /N m. 3TÜBİTAK / 114M15

Novel functional copolymers based on glycidyl methacrylate: Synthesis, Characterization, and Polymerization kinetics

A new methacrylate monomer 2-(4-nitrophenyl)-2-oxoethyl-2-methacrylate (NFM) was synthesized and its radical copolymerization with glycidyl methacrylate (GMA) was studied in 1,4-dioxane solution at 65 C using 2,2 0 -azobisisobutyronitrile as an initiator. The synthesized monomer and copolymers were characterized by FTIR, 1 H and 13 C-NMR spectroscopy. The analysis of reactivity ratios revealed that NFM is less reactive than GMA, and copolymers formed are statistically in nature. Thermogravimetric analysis of the polymers reveals that the thermal stability of the copolymers increases with an increasing in the mole fraction of NFM in the copolymers. Glass transition temperatures of the copolymers decreased with an increasing of NFM molar fraction in copolymers. In addition, according to the results obtained from the contact angle and zeta potential measurements the hydrophobic character of the polymer decreases (it means surface free energy increases) and its zeta potential becomes more negative with increase of NFM ratio in the copolymer. Polymers with carbonyl functional groups have been particularly interesting because of their use as photoresists.AKÜ-BAPK / 14-FENED-0

Determination of equilibrium, kinetic and thermodynamic parameters of Acid Red 88 adsorption onto montmorillonitic clay

The aim of this study is to evaluate adsorption kinetics, isotherms and thermodynamic parameters of anionic textile dye (Acid Red 88) onto montmorillonitic clay from aqueous solutions. The parameters of pH, initial dye concentrations, temperature, and the adsorbent dosage were investigated experimentally. Four kinetic models including pseudo-second order, pseudo-n order, Bangham’s equation and double exponential equation (DEE) were selected to follow the adsorption process. The dynamic data were fitted the DEE well and also followed the pseudo-n th order model. The adsorption data obtained were well described by the Langmuir isotherm model. The maximum adsorption capacity was found to be 588 mg/g at 20 o C. Thermodynamic parameters such as activation energy (E a ), Gibbs free energy (ΔG 0 ), enthalpy (ΔH 0 ) and entropy (ΔS 0 ) were also evaluated. The negative value of change in Gibbs free energy indicates that adsorption of AR88 on montmorillonitic clay is spontaneous. The anionic dye molecules can be adsorbed on montmorillonitic clay particles, even when their surface charge (or zeta potential) is negative. Interactions leading to adsorption of anionic dyes (AR88) onto the clay may cause from the following mechanisms: hydrogen bonding, electrostatic interaction, hydrophobic interaction, anion exchange and dye-dye interactions. The results show that montmorillonitic clay could be employed as low-cost material for the removal of acid dyes from textile effluents. thTÜBİTAK / 109Y16

Investigation on the Accuracy of Existing Qibla Directions of the Mosques from Different Periods: A Case Study in Çorum City, Turkey

The main goal of this study is to introduce two different approaches (i.e. based on spherical trigonometric formula and using sun qibla time) that can be used to determine the qibla directions of the existing mosques were oriented with sufficient accuracy according to Islamic criteria. In order to do this, eight mosques which were constructed in different periods, 14th, 16th, 17th and 21st centuries in Çorum City, Turkey, were handled. The existing qibla directions of each mosque were calculated with spherical trigonometric formula and compared with the precisely calculated real qibla directions. The existing qibla directions of the same mosques were once more compared with the real qibla directions which were determined by using the qibla time calculated based on the location and the time of the measurement. The results show that the qibla directions of the recently built mosques were oriented to Kâ’ba with higher accuracy while the earlier with more deviations. However, the results show that all the deviations were at acceptable levels in terms of Islamic criteria

Echinoderes dujardinii Claparède, 1863 (Kinorhyncha, Cyclorhagida): a new record for the kinorhynch fauna of Turkey

Meiobenthic samplings conducted in the framework of a meiobenthos project in the subtidal coastal waters of Sinop Bay, Southern Black Sea revealed the first report of the kinorhynch Echinoderes dujardinii for the marine fauna of Turkey.Depto. de Biodiversidad, Ecología y EvoluciónFac. de Ciencias BiológicasTRUEpu

Effect of mineral admixture type on rheological properties of polymeric self-consolidating mortar

Polimer matrisli kompozitler, simetrik ve dengeli malzeme özelliklerine sahip olmaları, üretim ve kullanım kolaylıklarından dolayı inşaat, hava-uzay yapıları ve otomobil yapıları için popülerlik kazanmaktadır. Günümüzde yeni kullanım alanı oluşturan polimerik malzemelerden birisi de epoksi esaslı kendiliğinden yerleşen harçlardır. Bu harçlar, inşaat sektöründe başta yüzey kaplamaları olmak üzere bina güçlendirmelerinde yaygın bir şekilde kullanılmaktadır. Bu malzemelerin yüzeye uygulanmasında hem yüksek olan maliyetlerinin azaltılması hem de dayanımlarının arttırılması amacıyla atık halde bulunan ve büyük ölçüde çevre kirliliği oluşturan malzemelerin filler olarak kullanımı araştırılmaktadır. Bu çalışmada yüksek fırın cürufu, uçucu kül, silis dumanı, kireçtaşı tozu ve doğal kum kullanılarak üretilen epoksi esaslı kendiliğinden yerleşen harçların viskozite, yayılma çapı ve katılaşma gibi reolojik özellikleri belirlenerek karakterize edilmiştir. Elde edilen deney sonuçlarına göre yüzey alanı yüksek olan mineral katkıların kullanım oranının artmasıyla polimer esaslı harçların işlenebilirliklerini azaltmıştır.Polymer matrix composites are gaining popularity for construction, air-space structures and automobile constructions due to their symmetrical and balanced material properties and their ease of production and use. One of the polymeric materials that make up the new application area is epoxy based self-consolidating mortar. These mortars are widely used in the construction industry, especially in surface coatings in building constructions. Both to reduce the high costs and to increase the strengths of these materials applied to the surface, i t i s bei ng i nvesti gated t he use of t he waste materi al s as a filler which cause environmental pollution. In this study, the rheological properties such as viscosity, spreading diameter and setting of epoxy based selfcompacting mortars produced by using blast furnace slag, fly ash, silica fume, limestone dust and natural sand have been characterized. According to the results of the experiment, the use of mineral admixtures wit h high surface area has been decreased the workability of polymer-based mortars.TÜBİTAK / 114M11

Farklı mineral katkıların epoksi zemin kaplama malzemesinin ıslanmazlığına ve yüzey enerjisine etkisi

Bu çalışmada epoksi esaslı zemin kaplama malzemesinin ıslanmazlık ve yüzey enerjisi üzerine mineral katkı türü ve miktarının etkisi incelenmiştir. Mineral katkı olarak üç farklı atık ürün (uçucu kül, silis dumanı ve yüksek fırın cürufu) ile kireçtaşı kullanılmıştır. Üretilen her bir katkılı ve katkısız epoksi malzemesinin ıslanmazlık özelliğinin belirlenmesinde, damla yayınım (sessile drop) yöntemi kullanılarak su ile temas açıları ölçülmüştür. Epoksi malzemelerin yüzey enerjisi hesaplamaları için ise 3 polar sıvı su, etilen glikol ve formamid ile 1 apolar sıvı diiodometan kullanılarak temas açıları ölçülmüş ve sonra bu temas açısı verilerine göre Fowkes yaklaşımı kullanılarak yüzey enerjileri hesaplanmıştır. Elde edilen sonuçlara göre, mineral katkılar az ya da çok epoksinin ıslanmazlık özelliğini düşürmekte ve buna uygun olarak yüzey enerjisini artırmaktadır. Katkı türleri içerisinde epoksinin ıslanmazlık ve yüzey enerjisi özelliklerine en az etki edenin uçucu kül ve en çok etki edenin ise kireçtaşı olduğu belirlenmiştir.In this study, the effect of type and amount of mineral additives on non-wettability and surface free energy of epoxy based floor coating material have been examined. Three different types of waste products (fly ash, fume silica and blast furnace slag) and limestone were used as mineral additive. Contact angle with water of each produced epoxy material with and without additive were measured by using sessile drop method to determine the hydrophobicity of the materials. For surface energy calculations of epoxy materials, their contact angles first were measured by using three polar (water, ethylene glycol and formamide) and one apolar (diiodomethane) liquid and their surface energies were then calculated according to these contact angles data by using Fowkes approach. Test results show that mineral additives have more or less decreased the hydrophobicity and increased surface energy. It was also determined that in additives fly ash has minimum and limestone has maximum effect on hydrophobicity and surface energy properties of epoxy.TÜBİTAK / 114M15

The Research of Sleep Disorders and Their Effects on Quality of Life in Patients with Chronic Renal Failure and Renal Transplant

Objective End stage renal insufficiency (ESRI) is defined as the irreversible loss of renal functions. In its treatment is used hemodialisis, peritoneal dialisis or renal transplantation. Sleep disorders cause excesive daytime sleepiness, mental problems, dysfunction in general health and functions; and therefore affect the quality of life in patients with ESRI. In this study is evaluated the relationship between sleep quality and the qulity of life in patients with hemodialisis, peritoneal dialisis and renal transplantation. Materials and Methods A total of 117 patients being treated in Uludağ University Faculty of Medicine Dialisis Unit between years 2011-2012 were enrolled. Pittsburg Sleep Quality Index (PSQI) were used to determine sleep quality of patients, and Epworth Sleepiness Scale (EUS) and Rolls Royce Quality of Life Scale were used. Results In PSQI, poor sleep quality was observed in 81.5% of patients with hemodialisis, which was 80.8% in patients with renal transplantation and 82% in patients with peritoneal dialisis. In Rolls-Royce Quality of life scale, general health, physical symptoms and activities were higher in patients with renal transplantation, and sleep disorders were higher in patients with hemodialisis. Conclusion Chronic renal insufficiency is a very common condition. Sleep disorders in these patients may affect self-care and show a negative influence on the quality of life. Fort his reason, sleep disorders should be questioned and treated in these chronically ill patients with ESRI

Spironolactone and colitis: Increased mortality in rodents and in humans

Background: Crohn's disease causes intestinal inflammation leading to intestinal fibrosis. Spironolactone is an antifibrotic medication commonly used in heart failure to reduce mortality. We examined whether spironolactone is antifibrotic in the context of intestinal inflammation. Methods: In vitro, spironolactone repressed fibrogenesis in transforming growth factor beta (TGF‐β)‐stimulated human colonic myofibroblasts. However, spironolactone therapy significantly increased mortality in two rodent models of inflammation‐induced intestinal fibrosis, suggesting spironolactone could be harmful during intestinal inflammation. Since inflammatory bowel disease (IBD) patients rarely receive spironolactone therapy, we examined whether spironolactone use was associated with mortality in a common cause of inflammatory colitis, Clostridium difficile infection (CDI). Results: Spironolactone use during CDI infection was associated with increased mortality in a retrospective cohort of 4008 inpatients (15.9% vs. 9.1%, n = 390 deaths, P < 0.0001). In patients without liver disease, the adjusted odds ratio (OR) for inpatient mortality associated with 80 mg spironolactone was 1.99 (95% confidence interval [CI]: 1.51–2.63) In contrast to the main effect of spironolactone mortality, multivariate modeling revealed a protective interaction between liver disease and spironolactone dose. The adjusted OR for mortality after CDI was 1.96 (95% CI: 1.50–2.55) for patients without liver disease on spironolactone vs. 1.28 (95% CI: 0.82–2.00) for patients with liver disease on spironolactone when compared to a reference group without liver disease or spironolactone use. Conclusions: We propose that discontinuation of spironolactone in patients without liver disease during CDI could reduce hospital mortality by 2‐fold, potentially reducing mortality from CDI by 35,000 patients annually across Europe and the U.S. (Inflamm Bowel Dis 2011;)Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/92045/1/21929_ftp.pd

Sectoral analysis of Nevşehir economy

Çalışmanın analiz birimini Nevşehir ili, çalışma konusunu ise ilin mevcut ekonomik yapısı oluşturmaktadır. Çalışma hazırlanırken ikincil verilerden yararlanılmıştır. Çalışmanın amacı Nevşehir’in ekonomik yapısının mevcut durumunu sektörler itibari ile incelemektir. Çalışmada sanayi, tarım ve turizm sektörleri bazı istatistiki göstergeler ile incelenmektedir. Nevşehir’in ekonomik gelişiminin incelenme sinin amacı, sektörlerin durumunu, karşılaştığı sorunları belirlemek, sorunlara çözüm önermek ve bölgede gelecekte yapılacak plan ve yatırımlara yön göstermektir.In this study, the main analysis unit is Nevsehir and the main subject is the economic structure in Nevsehir. The purpose of this study is to evaluate the current situation of economic structure in Nevsehir. To urism, agriculture and manufacturing sectors of the economy were examined in terms of some statistical indicators and secondary data was used. By examining the history of economic development in Nevsehir, it has been aimed to investigate the current problems of sectors faced in order to provide solutions to them and to lead the future planning and investment activities which will be carried out in the region