Acoustic Properties Of Polyurethane Composition Reinforced With Carbon Nano-tubes And Silicon Oxide Nano-powder

Tez (Yüksek Lisans) -- İstanbul Teknik Üniversitesi, Fen Bilimleri Enstitüsü, 2015Thesis (M.Sc.) -- İstanbul Technical University, Institute of Science and Technology, 2015Bu tez kapsamında gözenekli tipte (P-tip) ve küre şeklinde (S-tip) nano-silika tozlarının, karbon nanotüplerin ve bunların birbirleri ile karışımının poliüretan kompozisyonuna katılması ve oluşturulan köpük numunelerin akustik özellikleri incelenmiştir. Bu tez çalışmasında özellikle silisyum oksit nano tozları ve karbon nanotüpler ile güçlendirilmiş poliüretan kompozisyonunun akustik özellikleri araştırılmış olup, kütlece oranı % 2'yi geçmeyecek şekilde farklı oranlara sahip 40'dan fazla numunenin birbirleri ile kıyaslanarak en iyi akustik özelliklere  sahip olanları tespit edilmeye çalışılmıştır.  Tez kapsamında ses sönümleme kaybına ilaveten ses absorpsiyon katsayısı da araştırılmıştır. 40'a yakın farklı oranlarda numuneler üretilmiş ayrıca nano-silika ve karbon nanotüplerin birbirleri ile farklı oranlarda karıştırılması sağlanarak en iyi akustik özelliklere sahip malzemeye ulaşılmaya çalışılmıştır. Kütlece %1'e kadar farklı oranlarda karbon nanotüp eklenmiş numuneler içinde yapılmış deneylerde en iyi sonuca kütlece %0.2 karbon nanotüp eklenmiş poliüretan numunesinde ulaşılmıştır. Birbirleri ile yapılan kombinasyonlar içerisinde de kütlece %0.2 karbon nanotüp ve %1 p-tip nano-silika katılmış numunenin en iyi akustik değere sahip olduğu görülmüştür.In this thesis, in order to enhance acoustic properties of polyurethane foam, small amount of carbon-nanotubes and silicon oxide nanopowders were added to the polyol-isocyanate composition. In this thesis, acoustic properties of added small amount of carbon-nanotubes and silicon oxide nanopowders (S-type, P-Type) to the polyurethane composition were determined. By adding CNTs and/or nano-silica in the form of powder or liquid at different concentrations up to 2% within the PU composition to improve the sound absorption were investigated in the frequency range up to 6400 Hz. In this thesis, both CNTs and nano-silica (SiO2) particles were added with different quantities to the isocyante-polyol composition. The properties, especially the sound absorption, were studied for all the prepared samples and results were investigated to come up with the best nanocomposites that can be applied for sound absorption application at the desired operating frequency.   The results of sound transmission loss and absorption coefficient were determined and compared. As expected, it was found that most of samples were either good in STL or good in absorption. However, some combinations can achieve a balance of performance in both categories.Yüksek LisansM.Sc

THE EFFECT OF THE KODALY METHOD ON THE PRIMARY SCHOOL STUDENTS' ABILITY OF PLAYING THE VIOLIN

Bu araştırmanın amacı, Kodaly yönteminin ilköğretim öğrencilerinin keman çalma becerisi üzerindeki etkisini araştırmaktır. Ön test-son test kontrol gruplu yarı deneysel desenin kullanıldığı bu araştırmada, 2007-2008 öğretim yılı bahar döneminde İzmir ilinde özel bir ilköğretim okulu'nda daha önceden herhangi bir çalgı eğitimi almamış 3,4 ve 5. sınıflarda öğrenim gören öğrenciler içinden; tek ses tekrarlama becerisi, ezgi tekrarlama becerisi, ritim tekrarlama becerisi, şarkı söyleme becerisi, keman çalmaya yönelik fiziksel uygunluk ve isteklilik göz önünde alınarak seçilmiş 13 öğrenci üzerinde gerçekleştirilmiştir. Araştırma sırasında haftada bir saat olmak üzere, deney grubunda (n=7) Kodaly yöntemi ile genel müzik eğitimi, kontrol grubunda (n=6) ise geleneksel müzik öğretimi uygulanmış, ayrıca her iki gruptaki öğrencilere haftada bir saat keman dersi verilmiştir. Araştırma sırasında her iki gruba da aynı şarkılar ve konular öğretilmiştir. Araştırma verileri araştırmacı tarafından geliştirilen Keman Çalma Gözlem Formu ile toplanmıştır. Araştırma bulguları, Kodaly yönteminin alt boyutlarından olan "bedensel kurulum" ve "teknik boyut" üzerinde etkili olmadığı, "müzikal boyut" üzerinde ise anlamlı düzeyde etkili olduğu yönündedir.In this study, our aim is to determine Kodaly method's affect upon the ability of playing the violin of primary school students. Pretest-postest controlled group model has been used. From among 3rd, 4th and 5th classes, 13 students who were studying at college in İzmir during the spring semester of 2007-2008 academic year, and who had never before had the education of any instrument were chosen regarding their skill of mono vocal repetition, repetition of melody and rhythm, their ability of singing, and physical suitability for playing the violin and their willingness. During the research, for an hour a week, to the experimental group (n=7) general musical education was taught through Kodaly method, while for the control group (n=6) traditional teaching method was used. In addition, students in both group were taught to play the violin for an hour a week. During the research the same subjects and the same songs were taught to both groups. Research data were gathered by the Playing the Violin Observation Form Data which was developed by the researcher himself. The research findings show that Kodaly method does not have a meaningful effect on "Physical situation" and "Technical dimension",which are the subdimensions of playing violin, on the other hand has a meaningful effect on "Musical dimension"

Carbohydrate metabolism after one year of using a gestodene containing monophasic oral contraceptive

Aim: To prospectively evaluate the effects of an oral contraceptive containing the progestin gestodene on carbohydrate metabolism in ordinary Turkish women Material / Method: Carbohydrate metabolism was prospectively evaluated in 53 normal women prior to and during their use of monophasic oral contraceptive containing the progestin gestodene plus ethinyl estradiol for one year. The women had a two hour oral glucose tolerance test using 75 gram glucose load, measuring serum glucose and insulin level, performed at the beginning of the contraceptive therapy and after one year. Results: The results demonstrate no significant changes in either of carbohydrate metabolic indices between the two tests.  Conclusion: The progestin containing contraceptive pill can be safely used in consideration of the carbohydrate metabolism

Investigation of The Relationship Between the Tactical Skills Used by Football Players and Their Maximum Performance Levels

This study was conducted to investigate the relationship between the tactical skills used by amateur and professional league football players and their excellent performance levels. A total of 906 licensed football players, including 671 male and 235 female athletes, who play at amateur and professional levels in football leagues, participated in the research. Three different forms were used as data collection tools: Personal Information Form, Tactical Skills in Sports and Excellent Performance in Sports Scale. According to the findings of the study, 25.9 of the football players participating in the study were female and 74.1% were male. While the mean age of female football players was 20.06±3.18, the average age of male football players was determined as 23.34±5.62. In the study, a significant difference was found between the sub-dimensions of tactical skills in sports and the total scores of male and female football players. Similarly, it has been observed that male athletes have higher scores than female athletes in excellent performance scores. According to the years of playing licensed football, there were significant differences in all sub-dimensions of the tactical skills of the football players, between the athletes who played football between 1-5 years and all other groups who played football for more years (

Long-term results of chronic achilles tendon ruptures repaired with V-Y tendon plasty and fascia turndown

Background: This study aimed to evaluate the long-term follow-up results of V-Y tendon plasty with fascia turndown, for repairing chronic Achilles tendon ruptures. Methods: Seventeen patients (12 males, 5 females), who were diagnosed with chronic Achilles tendon rupture and met the inclusion criteria, were included in the study. These patients received treatment by means of V-Y tendon plasty with fascia turndown from January 1995 to December 2001. Clinical outcomes of the patients were assessed by using isokinetic strength testing, questioning the patient regarding residual discomfort, pain, or swelling and having the ability to perform heel rises and using American Orthopaedic Foot & Ankle Society’s (AOFAS’s) Ankle-Hind Foot Scale score. Mean followup duration was 16 years (13-18 years). Results: Mean time from the injury to operative treatment was 7 months. Mean operative defect of Achilles tendon in neutral position after debridement was 6 cm. During the follow-up, the mean calf atrophy was 3.4 cm. The mean 30 degrees/s plantarflex and 120 degrees/s plantarflex peak torques were 89 and 45 Nm, respectively. The mean 30 degrees/s plantarflex peak torque deficiency was 16%. The mean 120 degrees/s plantarflex peak torque deficiency was 17%. The average peak torque deficiency was 17%. The pre- and postoperative mean AOFAS Ankle-Hindfoot Scale scores were 64 and 95, respectively. No patient had a rerupture. Superficial wound infection was treated with oral antibiotic therapy in 2 patients (11%). Conclusions: The V-Y tendon plasty with fascia turndown for repairing chronic Achilles tendon ruptures yielded results comparable with the literature regarding clinical outcomes. This method did not require synthetic materials for augmentation and was an economic alternative compared to other repair methods. Level of Evidence: Level III, retrospective comparative study

YERE BAĞLILIĞIN VE KENT KİMLİĞİNİN BİR MEKÂN ÜZERİNDEN İNCELENMESİ: İSRAİLEVLERİ (DİKMEN YAPI KOOPERATİFİ) ÖRNEĞİ

Bu çalışmada, kullanıcıların İsrailevlerini (Dikmen Yapı Kooperatifi) tercih etme nedenleri, yaşadıkları mekâna ve kent kimliğine yönelik bağlılık ve tutumlarının belirlenmesi amaçlanmıştır. Bu sebeple, araştırmanın amacına uygun olarak ‘Yere Bağlılık Ölçeği’ ve ‘Kent Kimliği Ölçeği’ kullanılarak kullanıcıların bağlılık ve tutumları belirlenmiştir. Yapılan anket sonucu İsrailevlerinde (Dikmen Yapı Kooperatifi) yaşayan 47 konut kullanıcısından elde edilen veriler istatistiksel yöntemlerle değerlendirilmiş ve bulgular kısmında sistematik bir sırayla ele alınmıştır. Sonuç olarak, yere bağlılık düzeylerinin ve kent kimliği tutumlarının bir mekân üzerinden incelendiği bu çalışmada mekânı deneyimleyen kullanıcıların yere bağlılık düzeyleri ve kent kimliği tutumları arasında pozitif ve anlamlı bir ilişki olduğu ortaya çıkmıştır. Bu, mekânın sadece fiziksel bir yapı olmadığını, aynı zamanda kent yaşamının bir parçası olduğu görülmüştür. Aynı zamanda mekân tasarımında kullanıcıların rolünün büyük önem taşıdığı tespit edilmiştir

Investigation of Architect and Non-Architect Participants’ Perceptual Evaluations on Different Period Mosque Facades

In architecture, perception based studies about building facades have become more popular. In recent studies, mostly residential buildings and business center type of buildings had been selected as target buildings. The lack of study of the perception of the facades of religious structures has created the basic motivation for this work. In the current study, the facade features of (Seljuk period, Ottoman period and Republic period) some important mosques from different periods were evaluated according to the adjective pairs of complexity, preference and impressiveness variables. Also, whether or not the general views of the mosques represent Islamic religion and their level of arousing curiosity were questioned. For this purpose, in the study, a total of 16 mosques were used. The results obtained from the participants as architect and non-architect are given. It is seen that the participant architects show a statistically more negative approach compared to those who are non-architects in the perceptual evaluations of the facades of the mosques for complexity variable. On the other hand, there was no statistically significant difference between the participants' evaluations of preference and impressiveness variables (at p <0.05 level)

Formaldehyde Emission in Different Positions of Wood-Based Boards Used in Interior Architecture

This research focused on determining the effects on the formaldehyde emission (FE) of the middle and edge parts of two different wood-based boards (WBBs) consisting of medium density fiberboard (MDF) and particleboard (PB), which are widely used in interior architecture. Samples with the thicknesses of 18 mm were analyzed for FE at a temperature of 20 °C and 65% relative moisture content for 1, 2 and 3 hours after manufacture. In the PB samples, the highest value values of FE (0.4119 ppm) was determined in the samples obtained from the center while the lowest emission values (0.0875) was observed in the samples obtained from the edge. In the MDF samples, the highest value of FE (0.3012 ppm) was determined in the samples from the center while the lowest emission values (0.1807 ppm) was observed in the samples from the edge. The PBs have a higher environmental impact (0.2497 ppm) than the MDFs (0.2454 ppm). For distances to minimum values (0.10 ppm), while the furthest value was 311% for the central samples of PB, the closest value was -12.5% for the edge samples of PB

Chemical and biological profiles of essential oil from different parts of Myrtus communis L. subsp. communis from Turkey

The present study reports chemical composition, antidiabetic, anti-inflammatory and antioxidant potential of essential oils from leaves and twigs of Myrtus communis L. subsp. communis from Turkey. Essential oils were obtained separately from leaves and twigs of Myrtus communis subsp. communis (MC) by hydrodistillation using a Clevenger-type apparatus. Chemical compositions were determined using GC/MS. Antidiabetic, anti-inflammatory and antioxidant activities of essential oils were tested by α-amylase inhibitory, 5-lipoxygenase inhibitory and DPPH/ABTS radical scavenging methods, respectively. The major compounds of essential oil of Myrtus communis subsp. communis leaves (MCLEO) were α-pinene (35.6%), 1,8-cineole (28.3%), linalool (10.5%), and limonene (8.2%), while the major constituents of essential oil of Myrtus communis subsp. communis twigs (MCTEO) were α-pinene (30.7%), 1,8-cineole (23.5%), p-cymene (13.3%) and limonene (11.9%). MCLEO and MCTEO showed good and moderate radical scavenging activity with IC50  values of 124.40 µg/mL and 390.10 µg/mL for ABTS radical, respectively. MCLEO and MCTEO exhibited significant radical scavenging activity with IC50 values of 34.13 µg/mL and 28.15 µg/mL for DPPH radical, respectively. Also, MCLEO and MCTEO displayed strong and good antidiabetic activity with IC50 values of 29.94 µg/mL and 159.80 µg/mL against α-amylase enzyme, respectively. Finally, MCLEO and MCTEO showed good anti-inflammatory activity with IC50 values 86.10 µg/ mL and 96.55 µg/mL against 5-lipoxygenase enzyme, respectively. From the present study it can be concluded that essential oils, especially MCLEO, possess good antidiabetic, anti- inflammatory and antioxidant activities. Also, this is the first study on chemical composition of MCTEO from Turkey, as well as on α-amylase inhibitory and 5-lipoxygenase inhibitory activities of MCLEO and MCTEO