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The extended cubic B-spline algorithm for a modified regularized long wave equation

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Chinese Physics B 2013年第4期22卷 75-80页

作者： I.Dag D.Irk M.SarI faculty of Science and arts Department of Mathematics and Computer Sciences Eskis ehir Osmangazi niversitesi Eskis ehir Turkey faculty of Science and arts Department of Mathematics Pamukkale niversitesi Denizli Turkey

A collocation method based on an extended cubic B-spline function is introduced for the numerical solution of the modified regularized long wave equation. The accuracy of the method is illustrated by studying the single solitary wave propagation and the interaction of two solitary waves of the modified regularized long wave equation.

关键词： collocation methods solitary waves

Energy distributions of multiple backscattered photons in materials

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Nuclear Science and Techniques 2018年第2期29卷 68-73页

作者： Asuman Ayd?n Department of Physics Faculty of Arts and SciencesBal?kesir UniversityCagis Campus

Backscattering of gamma photons from a material is of fundamental importance in radiation shielding,industrial and medical applications, radiation dosimetry,and non-destructive testing. In Compton scattering, incident photons undergo multiple scatterings within the material(target) before exiting. Gamma photons continue to soften in energy as the number of scatterings increases in a thick target; in other words, the energy of gamma photons decreases as the scatterings increase in case of a thick target and results in the generation of singly and multiply scattered events. In this work, the energy distribution of backscattered gamma photons with backscattering intensity and energy probabilities were calculated by using the Monte Carlo method for metallic, biological, and shielding materials with various thicknesses of slab geometry. The materials under study were targeted with gamma photons of 0.279, 0.662, 1.250, and 2.100 Me V energies. In addition, the energy distributions of multiply scattered gamma photons were studied for materials with infinite *** results are presented and discussed in detail by comparing with other Monte Carlo calculations.

关键词： Monte Carlo simulation Gamma photon Backscattering energy distribution Backscattering probability Compton scattering

Amphibians and Reptiles of Luzon Island, Philippines: the Herpetofauna of Pantabangan-Carranglan Watershed, Nueva Ecija Province, Caraballo Mountain Range

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Asian Herpetological Research 2018年第4期9卷 201-223页

作者： Paul Henric P. GOJO CRUZ Leticia E.AFUANG Juan Carlos T. GONZALEZ William SM.GRUEZO faculty Department of Biological Sciences College of Arts and Sciences Central Luzon State University faculty Animal Biology Division Institute of Biological Sciences College of Arts and Sciences University of the Philippines Los Ba?os Adjunct faculty Graduate School University of the Philippines Los Ba?os

We present detailed species accounts for fifty-nine(59) species of amphibians and reptiles(17 frogs, 14 skinks, 3 agamids, 6 gekkonid lizards, 2 varanids, and 17 snakes) from Pantabangan-Carranglan Watershed, which lies within the Caraballo Mountain Range, whose biota is poorly-known. This was also the first extensive survey of herpetofauna within the watershed. Together with data from previous literature reviews, our records bring the total number of species of amphibians and reptiles for the Caraballo Mountain Range to 66. Forty-two(42) species from the area were Philippine endemics, with 25 species recorded only from Luzon faunal region. Seven species of herpetofauna are associated with unresolved taxonomic issues(new species and species complexes needing taxonomic partitioning, e.g. splitting of species groups). Two species recorded from the area were rarely represented in museum collections. Major distributional and elevational range extensions were recorded for several species. Comparison with Luzon’s other mountain ranges showed that the Caraballo Mountain Range is similar, in terms of species composition, to the northern Sierra Madre and Cordillera Mountain Ranges. The result of this survey showed the Caraballo Mountain Range and its mountains as a possible new center of herpetofaunal diversity and endemicity within Luzon. The importance of the Caraballo Mountain Range as an important biogeographic link merits further study.

关键词： Caraballo mountain range diversity ecology habitat herpetofauna

Mechanical, electrical, and thermal properties of the directionally solidified Bi–Zn–Al ternary eutectic alloy

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International Journal of Minerals,Metallurgy and Materials 2014年第10期21卷 999-1008页

作者： M.Sahin E.adrli Department of Electronics and Automation Technical Vocational School of Sciences Nigde University Department of Physics Faculty of Arts and Sciences Nigde University

A Bi-2.0Zn-0.2A1 （wt%） ternary eutectic alloy was prepared using a vacuum melting furnace and a casting furnace. The samples were directionally solidified upwards at a constant growth rate （V= 18.4 μm/s） under different temperature gradients （G = 1.15-3.44 K/mm） and at a constant temperature gradient （G = 2.66 K/mm） under different growth rates （V= 8.3-500 μm/s） in a Bridgman-type directional so- lidification furnace. The dependence ofmicrostructure parameter （2） on the solidification parameters （G and V） and that of the microhardness （Hv） on the microstructure and solidification parameters were investigated. The resistivity （ρ） measurements of the studied alloy were per- formed using the standard four-point-probe method, and the temperature coefficient of resistivity （α） was calculated from the ρ-Tcurve. The enthalpy （AH） and the specific heat （Cp） values were determined by differential scanning calorimetry analysis. In addition, the thermal conductivities of samples, obtained using the Wiedemann-Franz and Smith-Palmer equations, were compared with the experimental results. The results revealed that, the thermal conductivity values obtained using the Wiedemarm-Franz and Smith-Palmer equations for the Bi-2.0Zn-0.2Al （wt%） alloy are in the range of 5.2-6.5 W/Km and 15.2-16.4 W/Km, respectively.

关键词： ternary eutectic alloys directional solidification microhardness electrical resistivity thermal conductivity

SYNTHESIS,CHARACTERIZATION,THERMAL DEGRADATION AND ELECTROCHEMICAL PROPERTIES OF OLIGO-4-m-TOLYLAZOMETHINEPHENOL

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Chinese Journal of Polymer Science 2006年第6期24卷 647-656页

作者： smet Kaya Yasin Bayrakli Department of Chemistry Faculty of Sciences and Artsanakkale Onsekiz Mart UniversityTR-17020 anakkaleTurkey

The oxidative polycondensation reaction conditions of 4-m-tolylazomethinephenol （4-TAMP） in the presence of air O2 and NaOCl as oxidants were studied in an aqueous alkaline medium between 50 and 90℃. The structures of the obtained monomer and oligomer were confirmed by FT-IR, UV-Vis, ^1H- and ^13C-NMR and elemental analysis techniques. The physical characterization was made by TG-DTA, size exclusion chromatography （SEC） and solubility tests. At the optimum reaction conditions, the yield of oligo-4-m-tolylazomethinephenol （O-4-TAMP） was found to be 62.50% （for air O2 oxidant） and 90.0% （for NaOCl oxidant）, respectively. According to the SEC analysis, the number-average molecular weight （Mn）, weight-average molecular weight （Mw） and polydispersity index （PDI） values of O-4-TAMP were found to be 2310, 2610 g tool 1 and 1. 13, respectively, using air O2, and 1390, 1710 g mol^-1 and 1.23, using NaOCl, respectively. According to TG-DTA analyses, O-4-TAMP was more stable than 4-TAMP against thermal decomposition. The weight losses of 4-TAMP and O-4-TAMP were found to be 68% and 58% at 1000℃. Electrical conductivity of the O-4-TAMP was measured, showing that the polymer is a typical semiconductor. Electrochemically, the highest occupied molecular orbital （HOMO）, the lowest unoccupied molecular orbital （LUMO） and electrochemical energy gaps （E＇g） for 4-TAMP are -5.96, -3.22 and 2.74 eV, respectively. The HOMO, LUMO and （E＇g） for O-4-TAMP are -5.78, -3.44 and 2.34 eV, respectively. According to UV-Vis measurements, optical band gaps （Eg） of 4-TAMP and O-4-TAMP were found to be 3.45 and 3. 1 0 eV, respectively.

关键词： Air O2 NaOCl Oligo-4-m-tolylazomethinephenol Oxidative polycondensation Thermal analysis Band gap Conductivity

Alternating-current losses in two-layer superconducting cables consisting of second-generation superconductors coated by U-shaped ferromagnetic materials

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Chinese Physics B 2013年第12期22卷 509-513页

作者： Ahmet Cicek Fedai Inanir Fedor Gmry Department of Physics Faculty of Arts and Sciences Mehmet Akif Ersoy University Department of Physics Faculty of Arts and Sciences Recep Tayyip Erdog an University Institute of Electrical Engineering Slovak Academy of Sciences Du'bravska' Cesta 9 842 39 Bratislava Slovakia

Alternating-current losses in a two-layer superconducting cable, each layer being composed of 15 closely-spaced rectangular wires made up of second-generation superconductors when the ends of wires are coated by either a non-magnetic or strong ferromagnetic material having a U profile is numerically investigated. Computations are carried out through the finite-element method. The alternating-current losses do not increase significantly if the relative permeability of the coating is increased three orders of magnitude, provided that the current amplitude is less than half of the critical current in a superconducting wire. However, the losses are much higher for ferromagnetic coating if the amplitude of the applied current oscillating at 50 Hz is close to the critical current. The ferromagnetic coating is seen to accumulate the magnetic field lines normally on its surfaces, while the field lines are parallel to the long axes of the wires, leading to more significant flux penetration in the coated regions. This facilitates a uniform low-loss current flow in the uncoated regions of the wires. In contrast, coating with a non-magnetic material gives rise to a considerably smaller current flow in the uncoated regions, whereas the low-loss flow is maintained in the coated regions. Moreover, the current flows in opposite directions in the coated and uncoated regions, where the direction in each region is converse for the two materials.

关键词： second-generation superconductor two-layer cable ferromagnetic coating U profile alternating-current losses

SYNTHESIS AND CHARACTERIZATION OF A NEW DYESTUFF POLYMER SOLUBLE IN ALKALINE AQUEOUS MEDIA

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Chinese Journal of Polymer Science 2013年第12期31卷 1632-1646页

作者： Ismet Kaya Aysel Ayd n Kevser Temizkan Canakkale Onsekiz Mart University Faculty of Sciences and ArtsDepartment of ChemistryPolymer Synthesis and Analysis Laboratory

Novel dyestuff polymers were successfully obtained through oxidative polymerization technique. The synthesized Schiff base and its polymer were soluble in alkaline＇aqueous medium and they have various colors in different solutions. Also, it can be said that the synthesized compounds are suitable as coloring agent （dyestuff） for textile applications. Fluorescence properties of the compounds were determined in DMF with different concentrations （mg/L）. Poly-tris（4- aminophenyl）methanol （P-TAPM） has quite high emission and excitation intensity values. Optical and electrochemical band gaps of the polymers were lower than those of the monomers indicating the more conjugated structure of the polymers. The oxidized states of the novel dyestuff compounds were examined by cyclic voltammetry （CV） technique. The solid state conductivity measurements showed that the synthesized polymers were semiconductors when exposed to the iodine vapour their conductivities could be increased. P-TAPM had the highest undoped conductivity. Thermal characterizations of the synthesized compounds were carried out by TG-DTA and DSC methods.

关键词： Dyestuff polymers Thermal properties Fluorescence Oxidative polymerization.

Annual effective dose values from^137Cs activity concentrations in soils of Manisa,Turkey

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Nuclear Science and Techniques 2018年第7期29卷 164-170页

作者： Sermin Cam Kaynar Department of Physics Faculty of Sciences and ArtsManisaCelal Bayar University45140 ManisaTurkey

In this study,the activity concentrations of the fallout radionuclide ^(137(Cs in 150 soil samples collected from 13 districts of Manisa Province were determined using a gamma ray spectrometer with a Na I(Tl) *** health risks to people resulting from external exposure were evaluated by estimating the outdoor absorbed gamma dose rate and annual effective dose rate(outdoor and indoor).The activity concentration of ^(137)Cs varied from 3.6 ± 2.0 to 124.1 ± 11.0 Bq kg^(-1),with an average value of43.3 Bq kg^(-1).The average values of the outdoor absorbed gamma dose rate and annual effective dose(outdoor plus indoor) were found to be 1.3 n Gy h^(-1),and 8.0 μSv y^(-1),(6.38 + 1.59 μSv y^(-1)),*** results were compared with internationally recommended values.

关键词： 137Cs 平均价值有效剂量土壤样品土耳其 gamma 放射性核种健康风险

Hamiltonian Formulation of Singular Lagrangians on Time Scales

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Chinese Physics Letters 2008年第5期25卷 1720-1723页

作者： JARAD Fahd BALEANU Dumitru MARAABA Abdeljawad Thabet Department of Mathematics and Computer Science Faculty of Arts and Sciences Cankaya University-06530 Ankara Turkey

The Hamiltonian formulation of Lagrangian on time scale is investigated and the equivalence of Hamilton and Euler-Lagrange equations is obtained. The role of Lagrange multipliers is discussed.

关键词： supernova explosion proto-neutron star shock wave