189 research outputs found
The diagnostic efficiency of ultrasound in characterization for thyroid nodules: How many criteria are required to predict malignancy?
No full textObjective: The purpose of this study was to define the criteria for use in differentiating benign and malignant nodules with the help of the receiver operating characteristic analysis and to increase the objective diagnostic accuracy of ultrasonography
İleri ekmeklik buğday hatlarının bazı agronomik ve kalite özelliklerinin belirlenmesi üzerine araştırmalar
No full textAraştırma Projesi -- Ege Üniversitesi, 2011Bornova ekolojik kosullarında 2009/2010 yetistirme döneminde tesadüf blokları deneme desenine göre 3 tekerrürlü olarak yürütülen bu arastırma, Ege Üniversitesi, Ziraat Fakültesi, Tarla Bitkileri Bölümü tarafından gelistirilen ekmeklik bugday durulmus hatlarının önemli agronomik ve ekmeklik kalite özelliklerinin belirlenmesi amacıyla yapılmıstır. Çalısmada bitki materyali olarak 17 ileri hat ve 3 standart çesit (Sagittario, Ziyabey-98 ve Basribey-95) kullanılmıstır. Çalısmada agronomik özellikler olarak tane verimi, basaklanma gün sayısı, bitki boyu, m2'de basak sayısı, basak uzunlugu, üst bogum uzunlugu, fertil kardes sayısı, basakta basakçık sayısı, basakta tane sayısı, basakta tane agırlıgı, bayrak yapak alanı, bayrak yapragı kın alanı ve hasat indeksi degerleri ölçümlenmistir. Kalite özelikleri olarak ise hektolitre agırlıgı, bin tane agırlıgı, nem oranı, kül miktarı, sedimantasyon degeri, protein miktarı, yas ve kuru gluten miktarı, gluten indeksi ve sertlik degerleri incelenmistir. Çalısma sonucunda agronomik ve kalite özellikleri ile tane verimi degerleri birlikte ele alındıgında standart çesitleri asan 7, 106, 108 ve 129 nolu hatların verimlerinin yüksek ve kalite düzeylerinin de yeterli olabilecegi anlasılmaktadır. Bu ileri hatlar tescil ettirilerek bölge bugday üreticilerinin kullanımlarına sunulabilecektir. Ayrıca agronomik ve kalite özellikleri bakımından üst sıralarda yer alan ileri hatların üstün oldukları özellikler bakımından bugday ıslah programında ebeveyn olarak degerlendirilebilecekleri de sonucuna varılmıstır.;Triticum aestivum L., bread wheat, genotype, yield, agronomical and quality traits.;Triticum aestivum L., ekmeklik bugday, genotip, verim, agronomik ve kalite özellikleri
A multiphase phase-field study of three-dimensional martensitic twinned microstructures at large strains
No full textA thermodynamically consistent multiphase phase-field approach for stress and temperature-induced martensitic phase transformation at the nanoscale and under large strains is developed. A total of N independent order parameters are considered for materials with N variants, where one of the order parameters describes A M transformations and the remaining N-1 independent order parameters describe the transformations between the variants. A non-contradictory gradient energy is used within the free energy of the system to account for the energies of the interfaces. In addition, a non-contradictory kinetic relationships for the rate of the order parameters versus thermodynamic driving forces is suggested. As a result, a system of consistent coupled Ginzburg-Landau equations for the order parameters are derived. The crystallographic solution for twins within twins is presented for the cubic to tetragonal transformations. A 3D complex twins within twins microstructure is simulated using the developed phase-field approach and a large-strain-based nonlinear finite element method. A comparative study between the crystallographic solution and the simulation result is presented.This is a pre-print of the article Basak, Anup, and Valery I. Levitas. "A multiphase phase-field study of three-dimensional martensitic twinned microstructures at large strains." arXiv preprint arXiv:2206.12576 (2022).
DOI: 10.48550/arXiv.2206.12576.
Copyright 2022 The Author(s).
Attribution 4.0 International (CC BY 4.0).
Posted with permission
Failure mechanisms in lithium silicon batteries
No full textLithium silicon (Li-Si) batteries offer more than ten times the theoretical specific capacity compared to current lithium ion battery technologies, by using a silicon anode. In practice however, the cycle life of Li-Si batteries is very limited. The large volume change of the silicon anode is known to be the main reason for this. Research on the volume changes during varying cell cycles and voltages is presented in this thesis and an experimental set up for a quasi in situ study of the SEI layer is suggested. Cycling tests with an amorphous silicon thin film of 220 nm deposited using magnetron sputtering on a copper foil current collector confirmed that the major cause of capacity loss is swelling of the silicon during lithiation, causing the silicon to detach from the current collector and resulting in significant capacity loss. Increasing the lower cut off voltage from 0 V to 0.2 V resulted in a slight improvement of cycle life. Silicon detachment also decreased as determined by SEM images. EFTEM and EDX mapping showed a clear split between a partially lithiated silicon layer on the surface and a pure silicon layer on the current collector side. It can be concluded that discharging Li-Si batteries to 0.2 V instead of 0 V is a promising method to reduce the swelling of silicon during lithiation.HREMQuantum NanoscienceApplied Science
Prenatal exposure to a non-steroidal anti-inflammatory drug or saline solution impairs sciatic nerve morphology: a stereological and histological study
No full textKaplan, Suleyman/0000-0003-1477-5002; AYYILDIZ, Mustafa/0000-0002-6594-3080; ulkay, muzaffer basak/0000-0002-0928-0462; Geuna, Stefano/0000-0002-6962-831X; Canan, Sinan/0000-0002-9864-1767WOS: 000260953300011PubMed: 18678241The toxic effect of non-steroidal anti-inflammatory drugs (NSAIDs) during development has been widely investigated. While it has been shown that these drugs impair central nervous development and compromise the neural activity, the effects of these substances on the development of peripheral nerves are still not clarified. In the present Study, sciatic nerves withdrawn from three experimental groups of 4-week-old rats, prenatally exposed to either saline solution, or cliclofenac sodium, and controls not exposed to any substance, were evaluated in terms of axon number, cross-sectional area of axon and myelin sheet thickness as well as of the ultrastructure of nerve fibers. Comparisons of stereological estimations among these three groups showed that axon number and mean axon cross-sectional area, but not average myelin sheet thickness, were significantly decreased in rats that were exposed to both diclofenac sodium and also to the saline solution, in comparison of the control group. Electron microscope analysis revealed, in both treated groups, deterioration of myelin sheaths that was more pronounced in rats that were exposed to cliclofenac sodium. Altogether, these findings show that the prenatal administration of both diclofenac sodium and saline solution impairs peripheral nervous system development, thus suggesting that this potential teratogenic effect should be also taken into consideration in the clinical use of these substances in pregnant patients. (C) 2008 ISDN. Published by Elsevier Ltd. All rights reserved
Making Better Batteries: Following Electrochemistry at the Nano Scale with Electron Microscopy
No full textWith the focus in automobile industry to switch from petroleum-based vehicles to all electric vehicles, the increasing demand on harvesting energy from renewable sources for a safer and greener future and the ever-increasing demand of the portable electronics systems, the need for better batteries is eminent. The ultimate aim of battery research is to develop a low cost, light and small battery that can deliver high-capacity and/or high power. Lithium and sodium batteries are the frontrunners in achieving this ultimate battery. A macro battery is composed of thousands of millions of nanoparticles. Thus, to prepare a better battery we must determine the respective effects of electrode nanoparticle size, shape, structure, grain–grain boundary, defects and doping on the battery performance. To do so electrode nanoparticles need to be probed at the nano-scale to find out the correlation between their morphology, structure and chemical properties and their evolution due to the battery charging-discharging with battery performance. In this thesis we have utilized the unique capability of electron microscope to resolve the microstructural and chemical information at the (sub)nanometer scale to probe the electrode nanoparticles for making better batteries
Reflections on methodology for assessing campus sustainability from a Turkish perspective
No full textAim: The author provides a critical reflection of the questionnaire discussed at the workshop “Methodology for assessing the campus sustainability from the perspective of multi-level antifragility” held on Friday 13 May at the WSB University in Wrocław. The author reflects from the background of his experience in Turkey. Design / Research methods: The author provides his own reflections and opinions, based on the discussions at the workshop. Conclusions / findings: It is very difficult to create a set of indicators making campus sustainability internationally comparable, as well as finding proper sources of information. A starting point in creating such indicators may be mistakes threatening organizational viability and external sustainability Originality / value of the article: The article provides critical feedback on an innovative approach towards research on campus sustainability. </jats:p
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