12 research outputs found
Optical properties of radially-polarised twisted light
We show that, in general, any type of radially-polarised paraxial twisted
optical mode carries only an axial total optical angular momentum (AM) where is the winding number and
is a constant. This mode, however, is shown to have zero spin angular momentum
(SAM), so it is endowed only with orbital angular momentum (OAM) and no SAM.
The helicity is found to be proportional to , hence radially-polarised
modes display chirality. When applied to a Laguerre-Gaussian (LG) mode our
treatment leads to a total helicity equal to , where
is the action constant. The factor , depends on
the sign, not the magnitude of and so the result holds for any
radially-polarised LG mode however large the magnitude of its winding number
is. The magnitude of the action constant and hence the
helicity are diminished for all such LG modes of large beam waist .Comment: 4 figure
Yaratıcı ve Eleştirel Düşünme Temelli Fen Laboratuarı Uygulamalarının Akademik Başarı ve Bilimsel Süreç Becerileri Üzerine Etkisi
A note on the Woods-Saxon potential
The wave Schrodinger and, to clarify one interesting point encountered in the
calculations, Klein-Gordon equations are solved exactly for a single neutron
moving in a central Woods-Saxon plus an additional potential that provides a
flexibility to construct the surface structure of the related nucleus. The
physics behind the solutions and the reliability of the results obtained are
discussed carefully with the consideration of other related works in the
literature. In addition, the exhaustive analysis of the results reveals the
fact that the usual Woods-Saxon potential cannot be solved analytically within
the framework of non-relativistic physics, unlike its exactly solvable
relativistic consideration
Two Electrons in a Quantum Dot: A Unified Approach
Low-lying energy levels of two interacting electrons confined in a
two-dimensional parabolic quantum dot in the presence of an external magnetic
field have been revised within the frame of a novel model. The present
formalism, which gives closed algebraic solutions for the specific values of
magnetic field and spatial confinement length, enables us to see explicitly
individual effects of the electron correlation.Comment: 14 page
The effect of creative and critical thinking based laboratory applications on creative and logical thinking abilities of prospective teachers
The purpose of this study was to examine the effect of creative and critical thinking based laboratory method on prospective primary teachers' creative and logical thinking abilities. This research was conducted with 90 prospective elementary school teachers who were enrolled in two classes of education faculty during the spring semester of the 2004-2005 academic year. Creative and critical thinking based laboratory applications were conducted in the experimental group, and traditional laboratory applications were conducted in the control group. As a result of the investigation, it was determined that the experimental group was more successful than the control group in terms of the logical thinking ability and creativity. Implications for science education at the teacher education level were discussed. Copyright (C) 2009 HKIEd APFSLT
Simple production experiment of poly (3-hydroxy butyrate) for science laboratories and its importance for science process skills of prospective teachers
WOS: 000272362000003Poly (3-hydroxybutyrate), PHB, is a biocompatible and biodegradable polymer accumulated in microorganism cells as a reserve material. PHB production in biotechnology laboratories has been carried out by using expensive instruments such as autoclave, a large thermostatted shaker, a freeze dryer, and an automatic refrigerated centrifuge. A very simple method of PHB production with Alcaligenes eutrophus for use in science teaching freshman laboratory is reported in this article. The study was conducted with 6 prospective elementary teachers. An ordinary glass 1 L jar, a 4L pressure cooker and thermostate for aquariums were used in fermentation process of the bacterium in nutrient solution containing table sugar as a substrate. In conclusion, the thermal and characterization data confirmed the PHB structure. Science Process Skills are investigated in this study. Qaulitative method was used to acquire data and analyze the science process skills experienced by the students in the experiment. The article discusses on development of some science process skills during the experimental process and gives suggestions for future use and research
The Observed Concept Errors About the "Resolution" Subject in the Daily Life Events of the Lycee Students
Bu araştırmanın amacı, 9., 10. ve 11. sınıf öğrencilerinin “çözünürlük” konusuna ilişkin kavram yanılgılarını tespit etmektir. Araştırmanın çalışma grubunu, Kdz. Ereğli ilçesinde kimya dersi öğretim programını uygulayan liselerde öğrenim gören toplam 300 öğrenci oluşturmaktadır. Elde edilen veriler istatistiksel olarak değerlendirilmiş ve “çözünürlük ” ile ilgili kavram yanılgıları sınıf düzeyleri göz önünde bulundurularak tespit edilmiş ve çapraz tablo analizi ile ortaya konmuştur. Öğrencilerin özellikle çözücü, çözünenin cinsi ve çözünme olayına etki eden faktörler gibi konularda kavram yanılgılarına sahip oldukları belirlenmiştir.The purpose of this study is determining the misconceptions of ninth, tenth and eleventh class students about the term: solubility. Three hundred high school students who received a chemical education in Kdz. Ereğli by the chemistry lessons program had been forming the working group of this research. The data collected were evaluated statistically and misconceptions regarding to solubility were determined by taking into consideration the level of classes. Misconceptions regarding to solubility were stated by cross-table analyses. It was determined that students had misconceptions especially related to solvent, dissolver type and factors effected to dissolving event
The effect of creative and critical thinking based laboratory applications on academic achievement and science process skills
Bu araştırmanın amacı, yaratıcı ve eleştirel düşünme temelli fen laboratuarı uygulamalarının sınıf öğretmeni adaylarının bilimsel süreç becerileri ve akademik başarı düzeylerine etkisini incelemektir. Bu araştırma, 2004-2005 akademik yılının ilkbahar döneminde, eğitim fakültesinin 2 farklı sınıfında bulunan 94 sınıf öğretmeni adayı ile gerçekleştirilmiştir. Deney grubunda, laboratuar uygulamaları, yaratıcı ve eleştirel düşünme temelli yapılırken, kontrol grubunda, geleneksel laboratuar uygulamaları gerçekleştirilmiştir. Bu çalışmanın sonucunda, deney grubundaki öğretmen adaylarının akademik başarı açısından, kontrol grubundaki öğretmen adaylarından anlamlı bir şekilde daha başarılı ve bilimsel süreç becerisi açısından da anlamlı bir şekilde daha gelişmiş oldukları belirlenmiştir. Çalışmadan elde edilen bulgular dikkate alınarak, fen eğitimi açısından, sonuçlar tartışılmıştır.The purpose of the study was to investigate the effect of creative and critical thinking based laboratory method on prospective primary teachers’ science process skills and academic achievement. This research was conducted with 94 prospective elementary teachers who were enrolled in two classes of education faculty in the spring semester of the 2004-2005 academic year. While the creative and critical thinking based laboratory applications were conducted in the experimental group, traditional laboratory applications were conducted in the control group. As a result of the investigation, it was determined that the experimental group was successful than the control group in terms of the science process skills and academic achievement. Implications for science education at the teacher education level were discussed
Köy Enstitüleri ve Lüleburgaz Kepirtepe Köy Enstitüsü tarihi
Ankara : İhsan Doğramacı Bilkent Üniversitesi İktisadi, İdari ve Sosyal Bilimler Fakültesi, Tarih Bölümü, 2014.This work is a student project of the The Department of History, Faculty of Economics, Administrative and Social Sciences, İhsan Doğramacı Bilkent University.by Yiğit, Aslı