Ahi Evran University

About: Ahi Evran University is a education organization based out in Kırşehir, Turkey. It is known for research contribution in the topics: Density functional theory & Ab initio. The organization has 842 authors who have published 2270 publications receiving 21904 citations.

The electronic and elasticity properties of new half-metallic chalcogenides Cu3TMCh4 (TM = Cr, Fe and Ch = S, Se, Te): an ab initio study

Abstract: The ternary copper-based chalcogenides Cu3TMCh4 (TM = Cr, Fe and Ch = S, Se, Te), which have simple cubic (SC) crystal structure and conform to P4¯3m space group with 215 space number, have been in...

Physical characterization of high methoxyl pectin and sunflower oil wax emulsions: A low-field 1 H NMR relaxometry study.

Abstract: Pectin-wax-based emulsion systems could be used to form edible films and coatings with desired water permeability characteristics. Pectin is often used in food industry due to its gelling and viscosity increasing properties. Physical properties of pectin are highly dependent on its esterification degree. Waxes are commonly used as edible coatings to enhance the water barrier properties of food products. This study focuses on preparing emulsions with sunflower oil wax (SFW) and high methoxyl pectin (HMP) at different concentrations for any possible edible film or coating formulations. Sunflower oil (SFO) was added as the dispersed oil phase to these emulsions. Characterization of the emulsions was performed by using particle size, rheology, and time domain nuclear magnetic resonance (NMR) relaxometry measurements. Effects of HMP concentration and the presence of SFO in the emulsion formulations were explored. Mean particle size values were recorded between 1 and 3 µm. Rheology measurements showed that increasing HMP concentrations and presence of SFO in emulsions resulted in more pseudoplastic behavior. NMR transverse relaxation times (T2 ) were measured to detect the differences between the emulsions. Relaxation spectrum analysis was also conducted for a detailed understanding of the transverse relaxations. Addition of SFO and higher HMP concentrations decreased the T 2 values of the emulsion systems (P < 0.05). However, T2 decreasing effect of SFO was compensated at 10% (w/w) HMP concentration showing that SFO was well dispersed in this particular emulsion formulation. Changes in the rheological behavior and relaxation times provided insight on the formation and stability of the emulsions. PRACTICAL APPLICATION: Findings of this study can be utilized and integrated to produce edible films and coatings with different water permeability characteristics. This study showed that NMR relaxometry parameters were also effective in monitoring and determining the physical characteristics of the pectin-wax-based emulsion systems as other conventional techniques including rheology and particle size measurements. Our NMR relaxometry findings were in correlation with the flow behavior and particle size results of the investigated emulsion systems.

Developing and Validating a Comprehensive Scale to Measure Perceived Barriers to Technology Integration

Abstract: The purpose of this study was to develop a comprehensive and a generic scale to measure perceived barriers to technology integration. To this end, 511 pre-service teachers for the factor structure of the scale were performed. Findings showed that the scale has 51 items and 14 factors explained 63.17% of total variance. CFA results confirmed the structure of the scale. Furthermore, convergent and divergent validity were examined, and results show that the scale has construct validity. The reliability of the scale was calculated by Cronbach’s alpha co-efficiency and composite coefficient of fourteen factors show that the scale is reliable. It is thought that this instrument will be a practical guide for all pre-service teachers, teachers, teacher educators, instructors in “Supporting Technology Integration” from the field of instruction, learning, teaching, curriculum development, learning environments, teacher education, educational technology, educational developments, measurement and evaluation, and educational statistics which are appropriate to the scope of the journal, and may help to get a contribution and high quality studies.

A DFT study on stability and electronic structure of AlN nanotubes

Abstract: Structural, energetic, electronic, reactivity and stability properties of armchair (3,3), (4,4), (5,5), (6,6), (7,7), (8,8), (9,9) and (10,10) aluminum nitride nanotubes (AlNNTs) with different diameter have been probed using density functional theory (DFT) in terms of Moreover, the chemical reactivity characteristics of AlNNTs have performed via some of the quantum molecular descriptors. Our results also indicate that the increasing diameter of AlNNTs gives rise to notable changes in the electronic structure of the AlNNTs. Moreover, results for UV/vis spectra of AlNNTs indicate that the maximum wavelength absorption lie in the range 188−194 nm. The number Al-N bonds and segregation phenomena of Al and N atoms in the AlNNTs have been investigated to better understand the stability of AlNNTs. Besides, the energy gap and chemical hardness enhance with increase diameter of AlNNTs, thus resulting in a rise in the stability, while the AlNNTs with smaller can be considered as a candidate for the adsorption of gas molecules and drugs for nano-electronic applications.

Examining the Association Between Executive Functions and Developmental Domains of Low-Income Children in the United States and Turkey.

Abstract: This study examined the relations between executive functions and developmental domains of preschool children from low-income families through an intercultural perspective in the U.S. and Turkey. A total of 471 children and their primary caregivers participated in the Turkey part of the study, while 286 children and their parents engaged in U.S. sample. Regression analyses revealed that fine motor, problem solving, and executive functions of children between two contexts were significantly different from each other. In the U.S., executive functions predicted communication, problem solving, and fine motor development, whereas in the Turkish sample, executive functions did not predict domain scores. Child gender predicted four of five developmental outcomes in the U.S., whereas maternal education predicted two of five outcomes in Turkey. In addition, invariance testing demonstrated that predictors to outcomes were not significantly different between the two countries. Country differences from the first set of outcomes were explained in the context of the research sites, children's socialization, and cultural expectations surrounding child development. This study raises questions about relations between executive functions and developmental domains for future research.