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Effective Mass SchrSdinger Equation via Point Canonical Transformation

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Chinese Physics Letters 2010年第7期27卷 28-31页

作者： Altug arda Ramazan Sever Department of Physics Education Hacettepe University Ankara 06800 Turkey Department of Physics Middle East Technical University Ankara 06531 Turkey

Exact solutions of the effective radial Schrodinger equation are obtained for some inverse potentials by using the point canonical transformation. The energy eigenvalues and the corresponding wave functions are calcul... 详细信息

关键词： Uses Transformation

Exact Solutions of the Morse-like Potential,Step-Up and Step-Down Operators via Laplace Transform Approach

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Communications in Theoretical Physics 2012年第7期58卷 27-30页

作者： Altug arda Ramazan Sever Department of Physics Education Hacettepe University Department of Physics Middle East Technical University

We intend to realize the step-up and step-down operators of the potential V (x) = V1 e 2βx+V2 e βx. It is found that these operators satisfy the commutation relations for the SU(2) group. We find the eigenfunctions and the eigenvalues of the potential by using the Laplace transform approach to study the Lie algebra satisfied the ladder operators of the potential under consideration. Our results are similar to the ones obtained for the Morse potential (β→β).

关键词： exact solution laplace transform non-central potential Schrdinger equation

Approximate Solutions of Dirac Equation with Hyperbolic-Type Potential

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Communications in Theoretical Physics 2015年第9期64卷 269-273页

作者： Altug arda Ramazan Sever Department of Physics Education Hacettepe University Department of Physics Middle East Technical University

The energy eigenvalues of a Dirac particle for the hyperbolic-type potential field have been computed approximately. It is obtained a transcendental function of energy, F(E), by writing in terms of confluent Heun *** numerical values of energy are then obtained by fixing the zeros on "E-axis" for both complex functions Re[F(E)]and Im[F(E)].

关键词： hyperbolic-type potential Dirac equation approxima

Bound State Solutions of Schrodinger Equation for Generalized Morse Potential with Position-Dependent Mass

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Communications in Theoretical Physics 2011年第7期56卷 51-54页

作者： Altug arda Ramazan Sever Department of Physics Education Hacettepe University Department of Physics Middle East Technical University

The effective mass one-dimensional Schroedinger equation for the generalized Morse potential is solved by using Nikiforov-Uvarov method. Energy eigenvalues and corresponding eigenfunctions are computed analytically. The results are also reduced to the constant mass case. Energy eigenvalues are computed numerically for some diatomic molecules. They are in agreement with the ones obtained before.

关键词： position dependent mass Schr5dinger equation generalized morse potential Nikiforov-Uvarovmethod energy eigenvalues eigenfunctions

A New Segmentation Framework for Arabic Handwritten Text Using Machine Learning Techniques

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Computers, Materials & Continua 2021年第8期68卷 2727-2754页

作者： Saleem Ibraheem Saleem Adnan Mohsin Abdulazeez Zeynep orman Department of Information Technology Technical Informatics College of AkreDuhok Polytechnic UniversityDuhok42004Kurdistan RegionIraq Department of Computer Engineering Faculty of EngineeringIstanbul University-CerrahpasaIstanbul34320Turkey

The writer identification(WI)of handwritten Arabic text is now of great concern to intelligence agencies following the recent attacks perpetrated by known Middle East terrorist *** is also a useful instrument for the digitalization and attribution of old text to other authors of historic studies,including old national and religious *** this study,we proposed a new affective segmentation model by modifying an artificial neural network model and making it suitable for the binarization stage based on *** modified method is combined with a new effective rotation model to achieve an accurate segmentation through the analysis of the histogram of binary ***,propose a new framework for correct text rotation that will help us to establish a segmentation method that can facilitate the extraction of text from its *** projections and the radon transform are used and improved using machine learning based on a co-occurrence matrix to produce binary *** training stage involves taking a number of images for model *** images are selected randomly with different angles to generate four classes(0–90,90–180,180–270,and 270–360).The proposed segmentation approach achieves a high accuracy of 98.18%.The study ultimately provides two major contributions that are ranked from top to bottom according to the degree of *** proposed method can be further developed as a new application and used in the recognition of handwritten Arabic text from small documents regardless of logical combinations and sentence construction.

关键词： Writer identification handwritten Arabic biometric systems artificial neural network segmentation skew detection model

Zircon Zr isotope fractionation during crustal anatexis

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Science China Earth Sciences 2024年第8期67卷 2495-2506页

作者： Erlin ZHU Qiongxia XIA Zhaoya LI Renxu CHEN James VAN orman School of Earth and Space Sciences University of Science and Technology of ChinaHefei 230026China State Key Laboratory of Lithospheric and Environmental Coevolution Hefei 230026China Frontiers Science Center for Planetary Exploration and Emerging Technologies University of Science and Technology of ChinaHefei 230026China Department of Earth Environmental and Planetary SciencesCase Western Reserve UniversityCleveland OH 44106USA

Zirconium is one of high field strength elements but its isotope behavior during geochemical processes is still uncertain because of the limited *** Zr isotopes in magmatic rocks are often used to trace the evolution of magmas through fractional crystallization,it is intriguing how highly heterogeneous Zr isotopes were produced by the growth of zircon during crustal *** address this issue by in-situ zircon Zr isotope analyses of migmatites from two high-temperature metamorphic terranes in the South Lhasa zone and the North Dabie zone,respectively,in *** results show highly variable δ^(94)Zr values from-0.30‰ to +0.81‰ and from-0.58‰ to +0.49‰,*** addition to the relict zircon of magmatic origin,two types of newly-grown zircons were identified in terms of their occurrences,trace elements and δ^(94)Zr *** peritectic zircon,mainly occurring in the in-situ leucosomes,exhibits the highest Nb-Ta-Hf-U contents and variably higher δ^(94)Zr values than those of the relict *** anatectic zircon,mainly occurring in the leucocratic veins,shows higher Nb-Ta-Hf-U contents than and similar δ^(94)Zr values to those of the relict *** calculations demonstrate that the variable Zr isotope compositions of newly-grown zircons would result from decoupled release of Zr from zircon and non-zircon *** Zr supply of the peritectic zircon is mainly derived from the decomposition of Zr-bearing minerals in the in-situ anatectic melt(the non-zircon effect),whereas the Zr supply of the anatectic zircon is mainly from the dissolution of pre-existing zircons in the evolved melt(the zircon effect).The significant Zr isotope variations in the migmatites well illustrate the generation,migration and accumulation of the anatectic melts during the partial ***,Zr isotopes can be used as a powerful means for distinguishing between the peritectic and anatectic zircons during crustal anatexis.

关键词： Zr isotopes Zircon effect Non-zircon effect Migmatite Crustal anatexis

Enteral glutamine pretreatment does not decrease plasma endotoxin level induced by ischemia-reperfusion injury in rats

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World Journal of Gastroenterology 2008年第3期14卷 463-468页

作者： arda Demirkan Erkin Orazakunov Berna Sava■ M Ayhan Kuzu Mehmet Melli Department of Emergency Medicine Ankara University School of Medicine S1hhiye Ankara Turkey Department of General Surgery Ankara University School of Medicine S1hhiye Ankara Turkey Department of Pathology Ankara University School of Medicine S1hhiye Ankara Turkey

AIM:To investigate whether oral glutamine pretreatment prevents impairment of intestinal mucosal integrity during ischemia-reperfusion (I/R) in rats. METHODS: The study was performed as two series with 40 rats in each. Each series of animals was divided into four groups. The first group was used as a control. Animals in the second group were only pretreated with oral glutamine, 1 g/kg for 4 d. The third group received a normal diet, and underwent intestinal I/R, while the fourth group was pretreated with oral glutamine in the same way, and underwent intestinal I/R. Intestinal mucosal permeability to 51Cr-labeled EDTA was measured in urine in the first series of animals. In the second series, histopathological changes in intestinal tissue and plasma endotoxin levels were evaluated. RESULTS: Intestinal I/R produced a significant increase in intestinal permeability, plasma endotoxin level and worsened histopathological alterations. After intestinal I/R, permeability was significantly lower in glutamine- treated rats compared to those which received a normal diet. However, no significant change was observed in plasma endotoxin levels or histopathological findings. CONCLUSION: Although glutamine pretreatment seems to be protective of intestinal integrity, upon I/R injury, such an effect was not observable in the histopathological changes or plasma endotoxin level.

关键词： Endotoxin Glutamine Intestinal permeability Ischemia-reperfusion injury

Influence of zinc sulfate intake on acute ethanol-induced liver injury in rats

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World Journal of Gastroenterology 2006年第27期12卷 4345-4351页

作者： Sema Bolkent Pelin arda-Pirincci Sehnaz Bolkent Refiye Ya.ardag Sevim Tunali Sukriye Yildirim Department of Medical Biology Cerrahpasa Faculty of MedicineIstanbul UniversityCerrahpasa 34098IstanbulTurkey Department of Biology Faculty of ScienceIstanbul UniversityVezneciler 34459IstanbulTurkey Department of Chemistry Faculty of EngineeringIstanbul UniversityAvcilar 34850IstanbulTurkey

AIM： To investigate the role of metallothionein and proliferating cell nuclear antigen （PCNA） on the morphological and biochemical effects of zinc sulfate in ethanol-induced liver injury. METHODS： Wistar albino rats were divided into four groups. Group Ⅰ ; intact rats, group Ⅱ, control rats given only zinc, group ITl; animals given absolute ethanol, group Ⅳ; rats given zinc and absolute ethanol. Ethanol-induced injury was produced by the 1 mL of absolute ethanol, administrated by garage technique to each rat. Animals received 100 mg/kg per day zinc sulfate for 3 d 2 h prior to the administration of absolute ethanol. RESULTS： Increases in metallothionein immunoreactivity in control rats given only zinc and rats given zinc and ethanol were observed. PCNA immunohistochemistry showed that the number of PCNA-positive hepatocytes was increased significantly in the livers of rats administered ethanol ＋ zinc sulfate. Acute ethanol exposure caused degenerative morphological changes in the liver. Blood glutathione levels decreased, serum alkaline phosphatase and aspartate transaminase activities increased in the ethanol group when compared to the control group. Liver glutathione levels were reduced, but lipid peroxidation increased in the livers of the group administered ethanol as compared to the other groups. Administration of zinc sulfate in the ethanol group caused a significant decrease in degenerative changes, lipid peroxidation, and alkaline phosphatase and aspartate transaminase activities, but an increase in liver glutathione. CONCLUSION： Zinc sulfate has a protective effect on ethanol-induced liver injury. In addition, cell proliferation may be related to the increase in metallothionein immunoreactivity in the livers of rats administered ethanol ＋ zinc sulfate.

关键词： Liver Ethanol Zinc sulfate Metallothionein Proliferating cell nuclear antigen Rat

EXPERIMENTAL INVESTIGATION OF THE DURABILITY OF LOAD BEARING TIMBER-GLASS COMPOSITES UNDER THE EFFECTS OF ACCELERATED AGING

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Journal of Green Building 2019年第2期14卷 45-59页

作者： Halet Almila.arda Buyuktaskin Mehmet Serkan Yatagan Gulseren Erol Soyoz Leyla Tanacan Morvarid Dilmaghani Department of Architecture Faculty of ArchitectureIstanbul Technical UniversityTaskisla CampusTaksim34437 IstanbulTurkey

Although timber was used extensively as a structural material for traditional buildings in Turkey in the past, usage of structural timber decreased significantly over time and timber has been largely replaced by other materials. As timber is a natural, durable and sustainable material, it would be desirable to re-introduce timber structural elements to contemporary construction in a form that is appealing to industry. Timber-glass composite structural elements are potentially a good candidate for this purpose. To that end, a series of tests were conducted on load-bearing timber-glass composites in order to understand the long-term structural performance of the composite material under atmospheric conditions;to decrease the recurring cost of repair and maintenance;and to minimize the exhaustion of raw materials and energy. In this paper, the first part of this experimental work is presented, which focuses on the durability of timber-glass composite under the effects of accelerated aging, carried out on small-sized timber-glass composite specimens. Accelerated aging effects were observed under wetting-drying, freezing-thawing, UV effects, resistance to acids and high temperature. The mechanical strength of the timber-glass composite specimens before and after the effect of accelerated aging was measured by adhesion and shear strength tests and a comparative analysis of the results was carried out. The results of the experiments indicate that timber-glass composite is suitable to be used under protection from environmental conditions.

关键词： load bearing timber-glass composites adhesion test shear test durability test aging