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31.
İlke Taşçıoğlu Adem Tataroğlu Akif Özbay Şemsettin Altındal 《Radiation Physics and Chemistry》2010,79(4):457-461
The effect of γ-ray exposure on the metal–insulator–semiconductor (MIS) structures has been investigated using the electrical characteristics at room temperature. The MIS structures are irradiated with 60Co γ-ray source. The energy distribution of interface states was determined from the forward bias I–V characteristics by taking into account the bias dependence of the effective barrier height and ideality factor. The value of series resistance decreases with increasing dose. Experimental results confirmed that γ-ray irradiation have a significant effect on electrical characteristics of MIS structures. 相似文献
32.
Serap Beli Simon J. Coles Derya Davarc David B. Davies Michael B. Hursthouse Adem Kl 《Polyhedron》2007,26(18):5283-5292
Reaction of cyclophosphazene, N3P3Cl6 (1), with the sodium derivative of the fluorinated diol, 2,2,3,3,4,4-hexafluoropentane-1,5-diol (2), in THF solution at room temperature afforded five isolated products, whose structures have been characterised by X-ray crystallography and 1H, 19F and 31P NMR spectroscopy: the mono-spiro compound, N3P3Cl4(OCH2CF2CF2CF2CH2O) (3), its ansa isomer (4), a di-spiro derivative N3P3Cl2(OCH2CF2CF2CF2CH2O)2 (5), its spiro-ansa (6) isomer and the tri-spiro compound N3P3(OCH2CF2CF2CF2CH2O)3 (7). Quantitative 31P NMR measurements of the soluble portion of the reaction mixture show that in the reaction of (1) with the sodium derivative of the fluorinated pentanediol (2) there is a small preference for spiro compounds compared to ansa compounds (ratio ca. 1.3:1), similar to the analogous reaction of (1) with the sodium derivative of the fluorinated butanediol where there is a slightly greater proportion of spiro compared to ansa compounds (ratio ca. 1.5:1). The relative proportions of spiro and ansa compounds is likely to depend on the fine balance in stabilities of the different medium-sized rings in the fluorinated pentanediol (spiro, 8- and ansa, 10-membered rings) compared to the fluorinated butanediol (spiro, 7- and ansa, nine-membered rings) derivatives of cyclophosphazene. 相似文献
33.
Focusing properties of an acoustic lens based on a modified triangular sonic crystal slab whose columns are aligned on concentric
arcs of equal radial distance are investigated. Capability of focusing normally-incident plane waves is demonstrated by means
of Finite Element Method. Focusing mechanisms are discussed on the basis of band structures and equifrequency contours considering
a model where triangular lattice is elongated along ΓK direction. Focusing behavior of the proposed lens is argued to arise
from negative refractions at the air-lens interfaces accompanied by index guiding in its interiors. Wavelength-order confinement
in the transverse direction is observed. Double focusing is attributed to geometrical effects and contribution of self guiding
is discussed. Possibility of occurrence of birefraction at the input face of the lens together with positive refraction at
the output face is also discussed. 相似文献
34.
Chaudry Masood Khalique Abdullahi R. Adem 《Applied mathematics and computation》2010,216(10):2849-2496
In this paper, Lie group analysis is employed to derive some exact solutions of a generalized (3 + 1)-dimensional Kadomtsev-Petviashvili equation which describes the dynamics of solitons and nonlinear waves in plasmas and superfluids. 相似文献
35.
Adem Zengin Ugur Tamer Tuncer Caykara 《Journal of polymer science. Part A, Polymer chemistry》2013,51(16):3420-3428
A reversible addition‐fragmentation chain transfer (RAFT) agent was directly anchored onto superparamagnetic Fe3O4 nanoparticles (SPNPs) in a simple procedure using a ligand exchange reaction of 2‐[(dodecylsulfanylcarbonylthiolsulfanyl) propionic acid] (DCPA) with oleic acid initially present on the surface of Fe3O4 nanoparticles. The DCPA‐modified SPNPs were then used for the surface‐mediated RAFT polymerization of di(ethylene glycol) ethyl ether acrylate and (oligoethylene glycol) methyl ether acrylate to fabricate structurally well‐defined hybrid SPNPs with temperature‐responsive poly[di(ethylene glycol) ethyl ether acrylate‐co‐(oligoethylene glycol) methyl ether acrylate] shell and magnetic Fe3O4 core. Evidence of a well‐controlled surface‐mediated RAFT polymerization was gained from a linear increase of number‐average molecular weight with overall monomer conversions and relatively narrow polydispersity indices of the copolymers grown from the SPNPs. The resultant hybrid nanoparticles exhibited superparamagnetic property with a saturation magnetization of 55.1–19.4 emu/g and showed a temperature‐responsive phenomenon as the temperature changed between 25 and 40 °C. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013 , 51, 3420–3428 相似文献
36.
Xim Bokhimi Eduardo Muñoz José Luis Boldú Esbaide Adem Octavio Novaro Tessy López Fernando Rojas Ricardo Gómez Amado García-Ruiz 《Journal of Sol-Gel Science and Technology》2000,17(3):219-225
Sol-gel zirconia precursor, zirconium n-butoxide in ter-butanol, was irradiated with 1.3 MeV electrons to a dose of 330 KGy. Gelling was instantaneously produced when an aqueous solution of sulfuric, hydrochloric or acetic acid was added to the irradiated solution; no hydrolysis catalyst was required. Samples were characterized with X-ray powder diffraction, infrared spectroscopy, and electron paramagnetic resonance. The electron irradiation accelerated hydrolysis and condensation, which avoided the stabilization of the tetragonal phase via carboxyls, and decreased the capability of sulfate ions to stabilize it. These results suggest that the stabilization of the tetragonal phase of sol-gel zirconia via carboxyl and sulfate ions depends on their diffusion in the sol. 相似文献
37.
Three novel compounds (3–5) were synthesized from the reactions of non-geminal cis-2,4,6 diethylene glycol monobutyl ether substituted cyclotriphosphazene (2a) with ethylamine, hexylamine and dodecylamine. Compounds 3–5 were characterized by 31P NMR, MS and elemental analysis. The thermosensitive properties of compounds 3–5 were investigated. Compound 3 showed thermosensitive properties which might enable it to be used as a biomedical material. 相似文献
38.
A simple and fast flow injection fluorescence quenching method for the determination of iron in water has been developed.
Fluorimetric determination is based on the measurement of the quenching effect of iron on salicylic acid fluorescence. An
emission peak of salicylic acid in aqueous solution occurs at 409 nm with excitation at 299 nm. The carrier solution used
was 2 × 10−6 mol L−1 salicylic acid in 0.1 mol L−1 NH4+/NH3 buffer solution at pH 8.5. Linear calibration was obtained for 5–100 μg L−1 iron(III) and the relative standard deviation was 1.25 % (n = 5) for a 20 μL injection volume iron(III). The limit of detection
was 0.3 μg L−1 and the sampling rate was 60 h−1. The effect of interferences from various metals and anions commonly present in water was also studied. The method was successfully
applied to the determination of low levels of iron in real samples (river, sea, and spring waters). 相似文献
39.
40.
Gnül Yenilmez ifti Mahmut Durmu Elif enkuytu Adem Kl 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2009,74(4):881-886
This study dealt with the reactions of hexachlorocyclotriphosphazatriene, N3P3Cl6 (trimer) (1) with phenolphthalein (2) to give the phenolphthalein bridged compounds 3, 4 and 5. The phenolphthalein bridged cyclotriphosphazatriene derivatives are reported for the first time. The new compounds (3–5) are characterized by elemental analysis, mass spectrometry, UV–vis, FT-IR, 1H, 31P NMR and fluorescence spectroscopy. The more bridged phenolphthalein groups show the higher intensity of the absorption bands in the UV–vis spectra. Fluorescence spectrum of compound 3 shows a small band in the lower spectral range, while the spectra of compounds 4 and 5 show more intense and a band in higher spectral range. 相似文献