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71.
Influences of uniaxial elongation along the [11] direction of triangular and [10] direction of square sonic crystals under the constraint of conserved unit cell area are investigated by examining band structures and equi-frequency contours. Lowest-lying band gap of the triangular lattice observed at high filling fractions diminishes for negative elongation (compression), whereas another band gap develops at lower frequencies whose width reaches appreciable values for moderate elongation. The band gap of the square lattice, which appears at high filling fractions, is modified slightly with elongation. Frequency ranges of the bands, and thus the group velocities along the high-symmetry directions, vary with elongation which may be useful in applications like slow sound propagation. Elongation is observed to modify the equi-frequency contours significantly through reducing the lattice symmetry. The most prominent impact is the transformation of closed contours into open ones, whereas the rest are stretched either along or normal to the elongation axis of the 1st Brillouin Zone. This observation is utilized to implement wide-band all-angle self-collimation and superprism effect, which are demonstrated through Finite-Element computations. 相似文献
72.
In this study first we consider the singular integrals as generalized functions in two dimensions and then we solve the non-homogeneous wave equation with convolutional term by using the generalized functions as boundary conditions. 相似文献
73.
74.
Khadijo Rashid Adem Chaudry Masood Khalique 《Nonlinear Analysis: Real World Applications》2012,13(4):1692-1702
This paper obtains solutions to the Zakharov-Kuznetsov modified equal width equation with power law nonlinearity. The Lie symmetry approach and the simplest equation method are used to obtain these solutions. Moreover, conservation laws are derived for the underlying equation by employing two approaches: the new conservation theorem and the multiplier method. 相似文献
75.
Eçik ET Beşli S Çiftçi GY Davies DB Kılıç A Yuksel F 《Dalton transactions (Cambridge, England : 2003)》2012,41(22):6715-6725
Nucleophilic substitution reactions of N(3)P(3)Cl(4)[O(CH(2))(2)NCH(3)], (1) with the sodium salts of mono- and di-functional alcohols [methanol (2), phenol (3), tetraethyleneglycol (4) and 1,3-propanediol (5)] were carried out in order to investigate a possible directing effect of the spiro O-moiety on the formation of mono-substituted (2a, 3a), non-geminal di-substituted (2c, 3c) and ansa (4a, 5a) derivatives. Compounds isolated from the reactions were characterized by elemental analysis, mass spectrometry, (1)H and (31)P NMR spectroscopy and X-ray crystallographic analysis showed that the substituent OR in compounds (2a, 3a and 2c, 3c) and the ansa-ring in compounds (4a, 5a) formed cis to the P-O moiety of the exocyclic [O(CH(2))(2)NCH(3)] spiro ring. The formation of products (2a-d, 3a-d, 4a, 5a and 5b) was quantified from the (31)P NMR spectra of the reaction mixtures, which showed an overwhelming preference for derivatives (2a, 3a, 2c, 3c, 4a, 5a) with the substituent cis to the P-O moiety of the exocyclic spiro ring (2a, 3a, 2c, 3c, 4a, 5a), except for reaction with 1,3-propanediol where the six-membered ring spiro derivative (5b) was about three times more abundant than the eight-membered ring ansa-derivative (5a). Overwhelming formation of products with the substituent cis to the exocyclic P-O moiety is proof that the cation-assisted mechanism is responsible for the stereo-selectivity in the reactions with alkoxides. 相似文献
76.
Ali H. Al-Marzouqi Ayser Solieman Ihsan Shehadi Abdu Adem 《Journal of inclusion phenomena and macrocyclic chemistry》2008,60(1-2):85-93
Econazole (C18H15Cl3N2O) is one of the common antifungal agents whose poor aqueous solubility restricts its use for the treatment of oropharyngeal
candidiasis, which is the first symptom of HIV infection. Therefore, the aim of the current study was to investigate the effect
of different preparation methods (i.e. kneading, coevaporation, sealed-heating, and supercritical carbon dioxide (SC CO2)) for obtaining solid inclusion complexes between β-cyclodextrin and econazole. The physico-chemical properties of the different products were characterized by differential
scanning calorimetry (DSC), Fourier transform infrared spectroscopy (FTIR) and powder X-ray diffractometry (PXRD). For the
complexes prepared by the SC CO2 method, the effects of temperature and pressure have also been investigated and related to the solubility of econazole in
SC CO2. Results suggested the validity of the SC CO2 method for preparing solid complexes between cyclodextrins and econazole, avoiding the use of organic solvents and problems
of their complete removal. Moreover, temperature played a major role in promoting drug-carrier interactions, whereas pressure
had limited effects. 相似文献
77.
Saliha Begeç Sümeyya Alataş Adem Kılıç 《Phosphorus, sulfur, and silicon and the related elements》2013,188(7):1531-1537
Abstract In this work, the reactions of diphenylphosphinic chloride, (C6H5)2P(O)Cl, 1, with the sodium salts of sterically hindered phenol derivatives (2a-2j) were investigated. Novel alkyl-substituted aryl diphenyl phosphinate esters (C6H5)2P(O)OAr (3-12) were obtained from these reactions. Satisfactory analytical and spectroscopic results were obtained for all the new compounds. GRAPHICAL ABSTRACT 相似文献
78.
Abdullahi Rashid Adem Chaudry Masood Khalique Anjan Biswas 《Mathematical Methods in the Applied Sciences》2011,34(5):532-543
This paper studies the solution of the Kadomtsev–Petviasvili equation with power law nonlinearity in 1+3 dimensions. The Lie symmetry approach as well as the extended tanh‐function and G′/G methods are used to carry out the analysis. Subsequently, the soliton solution is obtained for this equation with power law nonlinearity. Both topological as well as non‐topological solitons are obtained for this equation. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
79.
80.
Uğur Tamer İsmail H. Boyacı Erhan Temur Adem Zengin İlker Dincer Yalçın Elerman 《Journal of nanoparticle research》2011,13(8):3167-3176
The preparation and application of rod-shaped core–shell structured Fe3O4–Au nanoparticles for immunomagnetic separation and sensing were described for the first time with this study. To synthesize
magnetic gold nanorod particles, the seed-mediated synthetic method was carried out and the resulting nanoparticles were characterized
with transmission electron microscopy (TEM), ultraviolet visible spectroscopy (UV–Vis), energy-dispersive X-ray (EDX), and
X-ray diffraction (XRD). Magnetic properties of the nanoparticles were also examined. Characterization of the magnetic gold
nanorod particles has proven that the resulting nanoparticles were composed of Fe3O4 core and the gold shell. The rod-shaped gold-coated iron nanoparticles have an average diameter of 16 ± 2 nm and an average
length of about 50 ± 5 nm (corresponding aspect ratio of 3). The saturation magnetization value for the magnetic gold nanorod
particles was found to be 37 emu/g at 300 K. Rapid and room temperature reaction synthesis of magnetic gold nanorod particles
and subsequent surface modification with E. coli antibodies provide immunomagnetic separation and SERS application. The analytical performance of the SERS-based homogenous
sandwich immunoassay system with respect to linear range, detection limit, and response time is also presented. 相似文献