Spectral splits of neutrinos as a BCS-BEC crossover type phenomenon

We show that the spectral split of a neutrino ensemble which initially consists of electron type neutrinos, is analogous to the BCS-BEC crossover already observed in ultra cold atomic gas experiments. Such a neutrino ensemble mimics the deleptonization burst of a core collapse supernova. Although these two phenomena belong to very different domains of physics, the propagation of neutrinos from highly interacting inner regions of the supernova to the vacuum is reminiscent of the evolution of Cooper pairs between weak and strong interaction regimes during the crossover. The Hamiltonians and the corresponding many-body states undergo very similar transformations if one replaces the pair quasispin of the latter with the neutrino isospin of the former.Comment: 9 pages, 5 figure

Mechanics of milling 48-2-2 gamma titanium aluminide

Accurate and fast prediction of cutting forces is important in high-performance cutting in the aerospace industry. Gamma titanium aluminide (gamma-TiAl) is a material of choice for aerospace and automotive applications due to its superior thermo-mechanical properties. Nevertheless, it is a difficult to machine material. This article presents the prediction of cutting forces for Ti-48Al-2Cr-2Nb (48-2-2) gamma-TiAl in milling process using orthogonal to oblique transformation technique. The novelty of this paper lies in reporting the orthogonal database of 48-2-2 gamma-TiAl. Fundamental cutting parameters such as shear stress, friction angle and shear angle are calculated based on experimental measurements. Friction coefficients are identified for two different coating conditions which are AlTiN, and AlCrN on carbide tools. Predicted results are validated with the experimental cutting forces during end milling and ball-end milling operations for different cutting conditions. The simulated results showed good agreement with the experimental results, which confirms the validity of the force modelWOS:000568177300002Scopus - Affiliation ID: 60105072Science Citation Index ExpandedQ2ArticleUluslararası işbirliği ile yapılan - EVETAğustos2020YÖK - 2019-2

Waterpipe (narghile) smoking among medical and non-medical university students in Turkey

Objectives. This investigation was performed in order to determine the prevalence rate of waterpipe smoking in students of Erciyes University and the effects of some socio-demographic factors

Effect of fly ash on rebars bond strength in the expanded clay aggregate lightweight concrete [Wp?yw popio?u lotnego na wi?zanie pr?tów zbrojeniowych w betonie lekkim z kruszywem z ekspandowanej gliny]

[No abstract available

The role of motivation between perceived teacher support and student engagement in science class

This study aimed to investigate the relationships among the middle school students’ perceptions of science teacher support, students’ motivation and students’ engagement in learning science. Student motivation was addressed with task value and academic self-concept while student engagement included aspects of agentic, behavioural, emotional and cognitive engagement. In the study, survey method was used and the data were collected though previously validated self-report questionnaires. Valid data were obtained from 1006 middle school students enrolled in one of the nine public schools in Turkey. The path analysis revealed that perceived science teacher’s support positively predicted students’ task value and academic self-concept in science. Furthermore, students who reported high levels of task value and academic self-concept showed higher levels of engagement in science. Accordingly, it seems important for science teachers to listen to the students, behave fairly and help them to solve their problems in order to motivate them for learning science and increase their engagement in science class. © 2018, © 2018 Informa UK Limited, trading as Taylor & Francis Group