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61.
The electrohydrodynamic instability of the interface between two liquids with different physical and electrical properties in plane Poiseuille flow is used to form monodisperse droplets in a square channel. The drop size and formation rate are controlled by simply controlling the flow rates and the amplitude of the electric field applied across the channel. 相似文献
62.
Şükriye Nihan Karuk Elmas Furkan Ozen Kenan Koran Ibrahim Yilmaz Ahmet Orhan Gorgulu Serkan Erdemir 《Journal of fluorescence》2017,27(2):463-471
Solvent free synthesis of 6,7-dihydroxy-3-(3-chlorophenyl) coumarin (CFHC) was designed and obtained by the interaction of 2-(2,4,5-trimethoxyphenyl)-1-(3-chlorophenyl)acrylonitrile with pyridinium hydrochloride in the presence of silica gel by using microwave irradiation. The characterization of CFHC was confirmed by FT-IR, 1H, 13C, 13C–APT and 2D HETCOR spectroscopy methods. The optical behavior of CFHC towards metal ions was investigated by UV-visible and fluorescence spectroscopy. CFHC showed “on–off” type fluorescence response towards Cu2+ with high selectivity in aqueous solution (CH3CN/H2O, 9/1, v/v). Once binding with Cu2+, CFHC-Cu2+ complex also displayed high selectivity for sulfide, resulting in “off–on” type sensing of sulfide anion. 相似文献
63.
Photophysical constants of three novel ruthenium dyes derived from tridentate pyridinediimine (pydim) ligands has been declared
and their photoluminescent properties were investigated in solvents of dichloromethane (DCM), tetrahydrofuran (THF) and ethanol
(EtOH) by UV-Visible absorption, emission and excitation spectra. The quantum yield, fluorescence decay time, molar extinction
coefficient and Stoke’s shift values of the novel ruthenium complexes were determined. The perfluoro compound (PFC) nonadecafluorodecanoic
acid which is also known as medical gas carrier has been used for the first time together with newly synthesized Ruthenium
complexes in ethyl alcohol. The utilities of oxygen sensing materials were investigated in EtOH in presence of chemically
and biochemically inert PFC. 相似文献
64.
Arif Sanli Ozlem Celebi Mehmet Eken Alev Oktay Sedat Aydin Emin Ayduran 《Journal of voice》2008,22(2):238-244
SUMMARY: Visualization of enlarged laryngeal lesions is the most important factor in choosing a surgical technique, especially for partial surgery. For this reason standard microlaryngoscopy, a computed tomography (CT) scan of the larynx, and 30 degrees telescopic microlaryngoscopy were compared during evaluation of the laryngeal ventricul and sub-glottic area. The histopatholgoical findings of the specimens collected under each modality were simultaneously compared. Comparison of the histopathological findings, which corresponded to inspection with the 30 degrees telescopic method, was more significant than with the use of standard microlaryngoscopy or the CT scan. The aim of the current study therefore was to determine the importance of the 30 degrees telescopic microlaryngoscopic method for the evaluation of the laryngeal ventricle and subglottic area. 相似文献
65.
Ozlem Yesiltas 《中国物理快报》2008,25(4):1172-1174
We show that a wide class of non-central potentials can be analysed via the improved picture of the Nikiforov- Uvarov method [Physica Scripta 75 (2007) 686]. It has been shown that using the alternative approach, polynomial solutions of three-dimensional separable non-central potential can be obtained. 相似文献
66.
We have achieved, for the first time to our knowledge, lasing in a new type of telluride-tungstate glass host doped with neodymium: Nd3+:(0.8)TeO2-(0.2)WO3. Lasing was obtained at 1065 nm with two samples containing 0.5 mol% and 1.0 mol% Nd2O3. During gain-switched operation, slope efficiencies of 12% and 10% were obtained with the 0.5 mol% and 1.0 mol% doped samples, respectively, at a pulse repetition rate of 1 kHz. Judd-Ofelt analysis was further employed to determine the emission cross section σe at 1065 nm from the absorption spectra and lifetime data. The emission cross section from the Judd-Ofelt analysis came to 3.23 ± 0.09 × 10−20 cm2, in reasonable agreement with the value of 2.0 ± 0.13 × 10−20 cm2 obtained from the analysis of laser threshold data. 相似文献
67.
G. Bilir G. Ozen J. Collins B. Di Bartolo 《Applied Physics A: Materials Science & Processing》2014,115(1):263-273
In this study we have synthesized Y2O3 (yttria) nanopowders with 1 % Nd3+ concentration by using a thermal decomposition method and investigated the effect of annealing temperature on the particle sizes and the effect of particle sizes on the spectroscopic properties of these systems. The particle sizes were effectively controlled by synthesis and annealing temperatures; the sizes were found to vary in the 15–290 nm range. The particle sizes and cubic phase of the yttria were determined by using XRD patterns and confirmed by SEM and TEM measurements. We note that the particle sizes increase by increasing the synthesis and annealing temperatures. Temperature dependence of the width and position of a selected spectral line were successfully fitted with the theoretical expressions. We studied thoroughly the behavior of the samples under pulsed excitation and give plausible explanations of the measured effects. 相似文献
68.
69.
In this study, polyindole (PIN)/TiO2 nanocomposites were synthesized with and without the presence of sodium dodecylsulfate, anionic surfactant, with two different PIN contents. The synthesized materials were subjected to various characterizations namely: particle size, apparent density, conductivity, dielectric constants, magnetic susceptibility, elemental analysis, Fourier transform infrared spectroscopy spectroscopy, thermogravimetric analysis, X-ray diffraction, scanning electron microscopy, and transmission electron microscopy. Characterization results revealed the successful preparations of PIN/TiO2 hybrid nanocomposites. Electrokinetic properties of all the materials were determined by zeta (ζ)-potential measurements in aqueous and nonqueous media. Effects of pH, temperature, presence of various electrolytes, and surfactants on electrokinetic properties of the materials were examined. 相似文献
70.
A thermoplastic stress and strain calculation is made to analyze the energy distribution around an energy source traveling in a prestretched panel. The technique of finite element is applied such that the motion of the energy source is discretized into a finite number of time increments. Remeshing of the grid pattern is carried out for every time increment.The energy source may represent a welding torch or laser beam with a high local intensity that causes the material to deform beyond its elastic limit and experience permanent damage by evaporation. This reduces the local stiffness and can lead to global instability. The failure analysis is based on the application of the strain energy density theory which is into the incremental theory of thermoplasticity. The specific example involves examining the experimental data of a 7075-T651 aluminum panel subjected to tensile loading. The energy source is assumed to have a finite radius and travels along the line of symmetry being normal to the direction of applied tension. The possible failure location is predicted for each time increment by analyzing the fluctuation of the local strain energy density field. A critical point corresponding to incipient fracture is found. The panel has a width of 45.72 cm and length of 55.88 cm. The prediction is consistent with the experimental observation. 相似文献