Tribological behaviour of polymer nanocomposities containing tungsten based nanoparticles

Thesis (Master)--Izmir Institute of Technology, Materials Science and Engineering, Izmir, 2007Includes bibliographical references (leaves: 81-83)Text in English; Abstract: Turkish and Englishxii, 83 leavesThe use of nanostructured fillers in epoxy systems has a significant role on the development of thermosetting composites. Recent investigations on inorganic nanoparticles filled polymer composites reveal their significant potential in producing materials with low friction and/or high wear resistance. In the present study, epoxy nanocomposites and fiber reinforced polymer (FRP) composites were prepared with the addition of tungsten based nanostructured particles which are produced by mechanical alloying. The effects of the nanostructured additives on the tribological, mechanical and thermal properties of composite laminates and nanocomposites were investigated. Composite laminates with and without filler were manufactured by using hand lay-up technique and cured under compression. It was found that tungsten based particle loading has no significant effect on the flexural properties of the nanocomposites and the composite laminates, and the tensile properties of the nanocomposites. It was found that while the addition of 3 wt. % of nanoparticles increases the hardness values, it significantly improves the wear resistance of nanocomposites. Furthermore, the significant improvement on the wear resistance was observed with the addition of 3 wt. % W-SiC-C (24h mechanical milling) powder onto the surface of fiber reinforced epoxy. The worn surfaces were examined with scanning electron microscopy (SEM) and the results revealed that wear mechanisms are altered due to the presence of nanoparticles in the matrix. Differential scanning calorimetry (DSC) results showed that nanoparticles have no significant effect on glass transition temperatures (Tg) of nanocomposites. Incorporation of nanoparticles increased the thermo mechanical properties of nanocomposites and composite laminates; including the storage and loss modulus and Tg

Scale, Patriotism and Fun: Crossing the Last Frontier of Fantasy

According to the rhetoric of a debate that erupted in Germany in 1933 under the leadership of Hermann Broch and was brought to a raging boil in America by Clement Greenberg in 1939, the California Sphinx is a prime example of kitsch

Milli Saraylar Sempozyumu 3.Basın Toplantısı

Taha Toros Arşivi, Dosya No: 120-Saraylarİstanbul Kalkınma Ajansı (TR10/14/YEN/0033) İstanbul Development Agency (TR10/14/YEN/0033)"Milli Saraylar Sempozyumu" Yürütme Komitesi Başkanı Prof. Dr. Metin Sözen'le yapılan söyleşiMilli Saraylarımı

Haptic's suitability to constructivist learning environment: aspects of teachers and teacher candidates

Until today many technologies are used in constructivist learning environments. As for this study, it is tried to reveal haptic's suitability to constructivist education environments together with aspects of 6 teachers and 21 teacher candidates. Semi-structured interview and qualitative methods are used for this study. In this study, it is revealed that haptic is suitable to constructivist learning environments by providing active, cognizing, exploring and meaningful learning. Showing the scene on the computer to the class with projector and using work sheets in the application were presented as solution to the problems. © 2009

A framework proposal for the design of video-assisted online learning environments for programming teaching

It is observed that in the wake of developments in digital technologies, the role of shareholders in the learning-teaching process changed and a transition from the classical face-to-face communication into online learning communication occurred. This transition also led to a change the knowledge and behaviours expected from indivudals. In this context, they are expected to acquire several skills considered as the skills of the 21st century, among which are critical and analytical thinking. Recent studies suggest that programming teaching is influential on these skills. However, programming teaching refers to a process which is structuraly difficult and complex. Thus, we need novel methods and techniques regarding programming teaching. Considering that particulalrly online learning environments have begun to be a crucial part of the learning-teaching process recently, it is believed that assisting onlne learning environments with learning videos in which audiovisual symbol systems are used together may play a crucial role in developing the programming skill that is abstract and unclear intuitively. From this point of view, this study aims to propose a framework related to desgning video-assisted online learning environments for programming teaching. To achieve this goal, the design-based research has been conducted. The research has been conducted through the participation of 48 (F: 27, M: 21) registered undergraduate students and of 4 instructors (F: 1, M: 3) of the Department of Computer Education and Instructional Technology based in the Faculty of Education at a state university located in the east of Turkey. Observation forms, reflective student diaries, the focus group interview, interview, and graded scoring key were used as data collection tools. As a result of the research, a framework has been proposed in the context of "content", "visual design", "interaction" and "practicability" related to the design of video-assisted online learning environments for "cognitive", "affective", "methodological" and "environmental" problems. Suggestions were presented within the framework of the results obtained from the study and the experiences of the researcher

Hybridization between Indian catfish, ♀Heteropneustes fossilis (Bloch) and Asian catfish, Clarias batrachus ♂ (Linn.)

Success has been achieved in intergeneric hybridization between two air breathing catfishes by crossing Indian catfish, Heteropneustes fossilis (Bloch) and Asian catfish, Clarias batrachus (Linn.) by in vitro fertilization technique. Four experimental trials were attempted and the highest fertilization (55.44%) and hatching (50.49%) rates were observed in the experiment IV. After 90 days of rearing, the growth rate of hybrids (65.3 ± 0.78 mm) was found to be higher than H. fossilis (55.2 ± 3.76 mm) and less than the C. batrachus (75.7 ± 0.9 mm). The survival rate of hybrids (24.75%) was observed to be less than H. fossilis (75.70%) and C. batrachus (73.13%). The karyological examination revealed that the hybrids possessed intermediate chromosomes (2n=53) between H. fossilis (2n=56) and C. batrachus (2n=50).  Morphologically, the hybrids resembled one of the parent’s C. batrachus and the dorsal fin was found almost in confluent with the tail fin.Keywords: Heteropneustes fossilis, Clarias batrachus, intergeneric hybridization, chromosomes, in vitro fertilizationAfrican Journal of Biotechnology Vol. 12(9), pp. 976-98

Usability of testing apparatuses about renewable energy resources in constructivist class environment

Students construct their own knowledge based on their experiences which take part in the basis of constructivism. For that reason, curriculums which are prepared according to constructivist approach should contain activities and materials to enable students to learn through exploring. In this study, it is tried to be determined the efficiency of a testing apparatus which enable students to learn renewable energy resources, energy cycle, hydrolysis of water events through exploring in education environments in the direction of teacher candidates. In conclusion, it is anticipated that in addition to its mentioned features, technology product apparatus will broaden the horizons of students in how to benefit from natural resources without damaging the environment with using technology. © 2009

Stochastic Integrals

Stochastické integrály Bakalářská práce - David Karal Abstrakt Tato práce se zabývá studiem Wienerova procesu a stochastických integrálů. V práci jsou definovány základní objekty stochastické analýzy a je ukázána existence Wienerova procesu a jeho vlastnosti. Tento proces je pak použit ke konstrukci Itôova stochastického integrálu. Itôův stochastický integrál je nejdříve definován pro jednoduché procesy a následně rozšířen pro Ft-progresivně měřitelné procesy. Potom je tento integrál zobecněn na stochastický integrál podle libovolného spoji- tého martingalu. V závěru práce je definován Stratonovičův integrál a je zkoumán jeho vztah s Itôovým integrálem. 1Stochastic Integrals David Karal Abstrakt In this thesis we study the Wiener process and stochastic integrals. The thesis defines the basic objects of stochastic analysis and the existence of the Wiener process and some of its properties are shown. This process is then used to con- struct the Itô stochastic integral, where the Wiener process acts as an integrator. The Itô stochastic integral is first defined for simple processes and subsequently extended to mathcalFt-progressively measurable processes. Then, the integral is generalized to stochastic integral driven by any continuous martingale. In the end of the thesis, the Stratonovich integral is defined and its relationship with the Itô integral is investigated. 1Department of Probability and Mathematical StatisticsKatedra pravděpodobnosti a matematické statistikyFaculty of Mathematics and PhysicsMatematicko-fyzikální fakult

QUIMBOL UMA POSSIBILIDADE PARA A EDUCAÇÃO FÍSICA ESCOLAR

Na noite do dia 30 de março de 2017 foi realizado com acadêmicos da 7ª fase do curso de Educação Física no Componente Curricular Esportes Complementares na Escola vivências práticas na modalidade Quimbol esporte esse surgido na cidade de Piracicaba São Paulo através das ideias do Professor Joaquim Bueno de Camargo