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排序方式: 共有140条查询结果,搜索用时 15 毫秒
21.
Beyrul Canbaz Cem Onem Fatma Aydogmus K. Gediz Akdeniz 《Chaos, solitons, and fractals》2012,45(2):188-191
Recently we have investigated the role of the coupling constant in the evolution of the two dimensional spinor-type instantons (Thirring Instantons [1]) in phase space [2] via Heisenberg ansatz. In this paper we study the stability of bifurcation points of the Thirring Instanton’s behaviours in phase space. 相似文献
22.
The practical application of adsorbents with the desired separation properties depends not only upon the adsorption characteristics of the material but also upon the mechanical properties of the packed bed. The packed bed, the vessel surrounding the bed and any internal structure that supports the bed are subjected to both static and cyclic loads during an adsorption process. In order to properly design the vessel and its internal structure, the bulk mechanical properties (most particularly the elastic properties) of the adsorbent bed must be known. The primary focus of this study was to determine the elastic properties of adsorbent beds packed with activated alumina, synthetic molecular sieve 13X or natural zeolite clinoptilolite. The bulk modulus of elasticity was found to be a linear function of applied stress for each of these materials in a range of stresses lower than the bulk crush strength. The Poisson’s ratio for the packed bed was also deduced from these results. 相似文献
23.
M. Cem Güçlü 《Progress in Particle and Nuclear Physics》2009,62(2):498-502
At LHC energies, the Lorentz factor will be 3400 for Pb+Pb collisions, and the electromagnetic interactions will play important roles. The cross sections for the electromagnetic particle productions are very large and cannot be ignored for the lifetimes of the beams and background. In this article, we are going to study some of the electromagnetic processes at the RHIC and the LHC and show the cross section calculations of the electron-positron pair production with the giant dipole resonance of the ions. 相似文献
24.
25.
Karanth N. Subbulakshmi Badiadka Narayana Hemmige S. Yathirajan Mehmet Akkurt
mer elik Cem Cüneyt Ersanl Christopher Glidewell 《Acta Crystallographica. Section C, Structural Chemistry》2015,71(8):742-751
Syntheses and structures are described for some alkylidene‐substituted dihydrooxazolones and dihydroimidazoles derived from simple acylglycines. A second, triclinic, polymorph of 4‐benzylidene‐2‐(4‐methylphenyl)‐1,3‐oxazol‐5(4H)‐one, C17H13NO2, (I), has been identified and the structure of 2‐methyl‐4‐[(thiophen‐2‐yl)methylidene]‐1,3‐oxazol‐5(4H)‐one, C9H7NO2S, (II), has been rerefined taking into account the orientational disorder of the thienyl group in each of the two independent molecules. The reactions of phenylhydrazine with 2‐phenyl‐4‐[(thiophen‐2‐yl)methylidene]‐1,3‐oxazol‐5(4H)‐one or 2‐(4‐methylphenyl)‐4‐[(thiophen‐2‐yl)methylidene]‐1,3‐oxazol‐5(4H)‐one yield, respectively, 3‐anilino‐2‐phenyl‐5‐[(thiophen‐2‐yl)methylidene]‐3,5‐dihydro‐4H‐imidazol‐4‐one, C10H15N3OS, (III), and 3‐anilino‐2‐(4‐methylphenyl)‐5‐[(thiophen‐2‐yl)methylidene]‐3,5‐dihydro‐4H‐imidazol‐4‐one, C21H17N3OS, (IV), which both exhibit orientational disorder in their thienyl groups. The reactions of 2‐phenyl‐4‐[(thiophen‐2‐yl)methylidene]‐1,3‐oxazol‐5(4H)‐one with hydrazine hydrate or with water yield, respectively, N‐[3‐hydrazinyl‐3‐oxo‐1‐(thiophen‐2‐yl)prop‐1‐en‐2‐yl]benzamide and 2‐(benzoylamino)‐3‐(thiophen‐2‐yl)prop‐2‐enoic acid, which in turn react, respectively, with thiophene‐2‐carbaldehyde to form 2‐phenyl‐5‐[(thiophen‐2‐yl)methylidene]‐3‐{[(E)‐(thiophen‐2‐yl)methylidene]amino}‐3,5‐dihydro‐4H‐imidazol‐4‐one, C19H13N3OS2, (V), which exhibits orientational disorder in only one of its thienyl groups, and with methanol to give methyl (2Z)‐2‐(benzoylamino)‐3‐(thiophen‐2‐yl)prop‐2‐enoate, C15H13NO3S, (VI). There are no direction‐specific intermolecular interactions in the crystal structure of the triclinic polymorph of (I), but the molecules of (II) are linked by two independent C—H...O hydrogen bonds to form C22(14) chains. Compounds (III) and (IV) both form centrosymmetric R22(10) dimers built from N—H...O hydrogen bonds, while compound (V) forms a centrosymmetric R22(10) dimer built from C—H...O hydrogen bonds. In the structure of compound (VI), a combination of N—H...O and C—H...π(arene) hydrogen bonds links the molecules into sheets. Comparisons are made with some similar compounds. 相似文献
26.
A novel Zn(II) ions imprinted poly (2-hydroxyethyl Methacrylate-N-methacryloyl-(L)-histidine methyl ester) poly(HEMAH) surface plasmon resonance (SPR) nanosensor were designed for detection of Zn(II) ions in aqueous solution and artificial plasma providing a low cost, rapid and reliable results compared to other techniques such as atomic absorption spectroscopy, inductively coupled plasma-mass spectrometer, X-ray fluorescence with synchrotron radiation. Zn(II) ions imprinted nanofilm on the SPR chip surface was synthesized by bulk polymerization. Characterization of Zn(II) ions imprinted nanosensor was performed by contact angle measurement, atomic force microscopy (AFM), ellipsometry and Fourier transform infrared spectroscopy-attenuated total reflection (FTIR-ATR). Designed nanosensor was applied for selective detection of Zn(II) ions in aqueous solution within the range of 0.5–1.0?µg/mL. The limit of detection (LOD) and limit of quantification (LOQ) were calculated as 0.19 and 0.64?ng/mL, respectively. Association kinetics analysis, Scatchard, Langmuir, Freundlich, Langmuir–Freundlich, Tempkin and Dubinin-Radushkevich isotherms were analyzed to the experimental data in order to identify the adsorption behavior. The selectivity of the SPR nanosensor was examined by using competitive metal ions such as Cd(II), Cu(II), Pb(II), and Fe(II). To evaluate the imprinting effect of Zn(II) ions imprinted (MIP) and non-imprinted (NIP) nanosensor was also prepared as the control. Repeatability of the response signal was tested by four times adsorption–desorption–regeneration cycle. 相似文献
27.
A similarity analysis was performed to investigate the laminar boundary-layer flow in the presence of a transverse magnetic
field over a down-pointing and spinning cone with mixed thermal boundary conditions. Boundary layer velocity and temperature
profiles were determined numerically for various values of the magnetic and spin parameters and the Prandtl number. The spin
of the cone compresses the velocity profiles towards the surface by inducing an upward flow and decreases the surface temperature.
The magnetic field suppresses the velocity profiles and increases the surface temperature. A transformation relating the similarity
solutions of the boundary-layer velocity and temperature profiles associated with different values of the mixed thermal boundary
condition parameter was obtained. 相似文献
28.
Bozkir Cem Deniz Caglar Kundakcioglu O. Erhun Henry Andrea C. 《Journal of Global Optimization》2022,83(3):565-584
Journal of Global Optimization - In this study, we consider a health network that faces uncertain supply disruptions in the form of regional, nationwide, or worldwide drug shortages. Each hospital... 相似文献
29.
Murat Celtek Sedat Sengul Unal Domekeli Cem Canan 《The European Physical Journal B - Condensed Matter and Complex Systems》2016,89(3):65
In this study, the temperature effects on the structural evolution of theZr70Pd30 binary alloy in the glassy and liquid states werestudied using the molecular dynamics simulations based on the many-body type tight-bindingpotential. We considered the following properties in detail: the temperature dependence ofthe volume, the partial and total pair distribution functions and the simulated glasstransition temperature. The effects of the cooling rates on the glass transitiontemperature were examined. The Wendt-Abraham parameter was calculated to determine theglass transition temperature of Zr70Pd30 glassy alloy. The pair analysis technique ofHoneycutt-Andersen was applied to define local atomic arrangements produced from moleculardynamics simulations. The results show that the icosahedral ordering in glassy state hasbeen composed during quenching period, and the simulated glass transition temperature andthe total pair distribution functions are in good agreement with the experimental data. 相似文献
30.
Many studies suggest strong hydrophilicity of plasma treated polyester surfaces. However, no studies have been reported on
the influence of plasma on the antibacterial activity of polyethylene terephthalate. First samples were padded with triclosan
as antibacterial agent with different concentrations. Second samples were treated by oxygen plasma with different operating
frequency and treating time, respectively. Afterwards, plasma treated samples were padded with triclosan in same conditions.
The results revealed that the antibacterial activity slighlty increased after treating with triclosan. SEM images and FTIR
spectra showed that horizontal channels were brought about on the fiber surface and then better surface roughness and wettability
were obtained by plasma. Fibers were fully coated with triclosan after plasma and the antibacterial activity increased with
increasing operating frequency and reaction time. Finally, the samples treated with triclosan after plasma gave acceptable
results and showed the best antibacterial activity for Staphylococcus aureus and Escherichia coli. 相似文献