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661.
Morteza Fotouhi 《Mathematical Methods in the Applied Sciences》2007,30(10):1121-1134
The singular sources method is given to detect the shape of a thin infinitely cylindrical obstacle from a knowledge of the TM‐polarized scattered electromagnetic field in large distance. The basic idea is based on the singular behaviour of the scattered field of the incident point source on the cross‐section of the cylinder. We assume that the scatterer is a perfect conductor which is possibly coated by a material and investigate two models with different boundary conditions. Also we give a uniqueness proof for the shape reconstruction. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
662.
A new plasticized PVC uranyl‐selective electrode based on a bis(2‐hydroxyacetophenone)ethylenediimine (BHAED) carrier by the direct coating of the membrane ingredients on the surface of a graphite disk electrode is reported. The electrode displayed high selectivity for uranyl ion toward a number of inorganic ions. The influence of the membrane compositions and pH, the effect of lipophilic cationic and anionic additives and plasticizer on the response properties of the electrode were investigated. The electrode exhibited a Nernstian slope of + 29.3 ± 1.2 for the uranyl ion concentration in the range of 5.0 × 10?6 ?0.05 M with detection limits of approx. 2.0 μM. The potentiometric responses of the electrode are independent of pH over the range of 3.0–4.5 with satisfactory reproducibility. The sensor has response times of <5 s and can be used for at least 2 months without considerable divergence in potential. 相似文献
663.
Ali Khalaj Morteza Pirali Hogatollah Matloubi Reza Dowlatabadi 《Monatshefte für Chemie / Chemical Monthly》2001,39(12):747-752
Several novel N-(2,3-dihydro-2-oxo-5-phenyl-1H-1,4-benzodiazepin-3-yl)-2-carboxamides were prepared by acyl coupling of 2-aminobenzophenones with α-(benzotriazol-1-yl)-N-acylglycines followed by displacement of the benzotriazole ring with ammonia and cyclization of the resulting monoacyl aminals. In addition to high yields and shorter reaction sequences due to avoiding deprotection and acylation of the protected 3-amino-1,4-benzodiazepin-2-one intermediates, the present approach did not involve the use of toxic and odoriferous materials as is the case with other methods. 相似文献
664.
A new general solution in terms of two scalar potential functions for classical elastodynamics of x
3-convex domains is presented. Through the establishment and usage of a set of basic mathematical lemmas, a demonstration of
its connection to Kovalevshi–Iacovache–Somigliana elastodynamic solution, and thus its completeness, is realized with the
aid of the theory of repeated wave equations and Boggio’s theorem. With the time dependence of the potentials suppressed,
the new decomposition can, unlike Lamé’s, degenerate to a complete solution for elastostatic problems.
相似文献
665.
Amir Alaei Morteza Hasanzadeh Kafshgari Shahab Kashani Rahimi 《Heat and Mass Transfer》2013,49(2):285-290
New experimental results present the effects of low-frequency vibrations in a vertical heat pipe. The thermal resistance was investigated under different heat transfer rates, filling ratios and frequencies, increase of which improved the thermal performance. The vibrations were effective 33.83 % on the performance, and the best performance was estimated using the L16 array of Taguchi method, and it was achieved with the thermal resistance 0.064 K/W in the frequency 30 Hz. 相似文献
666.
Morteza Yavari 《理论物理通讯》2013,59(1):125-130
In this letter,we are going to use a geometrical approach to describe the free energy of DNA structures.The exact solutions of the equilibrium shape equations in a general WLC model for DNA forms by using the Feoli's formalism [A.Feoli,et al.,Nucl.Phys.B 705(2005) 577] are studied.Then,the free energy of transition between Band Z-DNA is calculated in this formalism. 相似文献
667.
A transversely isotropic material in the sense of Green is considered. A complete solution in terms of retarded potential
functions for the wave equations in transversely isotropic media is presented. In this paper we reduce the number of potential
functions to only one, and we discuss the required conditions. As a special case, the torsionless and rotationally symmetric
configuration with respect to the axis of symmetry of the material is discussed. The limiting case of elastostatics is cited,
where the solution is reduced to the Lekhnitskii–Hu–Nowacki solution. The solution is simplified for the special case of isotropy.
In this way, a new series of potential functions (to the best knowledge of the author) for the elastodynamics problem of isotropic
materials is presented This solution is reduced to a special case of the Cauchy–Kovalevski–Somigliana solution, if the displacements
satisfy specific conditions. Finally, Boggio's Theorem is generalized for transversely isotropic media which may be of interest
to the reader beyond the present application.
Dedicated to Morton E. Gurtin 相似文献
668.
Evaluation of liposomal delivery of antisense oligonucleotide by capillary electrophoresis with laser-induced fluorescence detection 总被引:1,自引:0,他引:1
Two widely used commercial cationic liposome formulations, Lipofectamine and Escort, were evaluated for drug delivery efficacy with capillary electrophoresis coupled with laser-induced fluorescence detection using a fluorescein conjugated 2'-O-methyl-phosphorothioate (Me-PS) antisense oligonucleotide and the HeLa cell line. Binding constants were estimated by monitoring changes in the electrophoretic mobility of the oligonucleotide with the liposome solution in the running buffer. From these changes in mobility, the binding constants for Lipofectamine and Escort liposomes with Me-PS oligomer were estimated to be 1139 and 590 M(-1), respectively. Additionally, intracellular concentrations and gene expression were quantified for the liposome formulations. 相似文献
669.
Mohammad Kazemi Ashtiani Mojgan Zandi Parvin Shokrollahi Morteza Ehsani Hossein Baharvand 《先进技术聚合物》2020,31(4):741-748
Therapeutic contact lenses have attracted significant attention during the last decades. In this study, we used chitosan‐conjugated poly(2‐hydroxyethyl methacrylate) (PHEMA) for contact lens application. We aimed to increase affinity of anionic drugs, which are used in treatment of eye diseases. In this regard, we evaluated delivery of the small molecule anionic drug, ascorbic acid from the chitosan‐conjugated PHEMA. Chitosan immobilization improves drug loading efficiency and induces sustained release of ascorbic acid. The chitosan modified hydrogel also reduces the biofouling of tear fluid components. Our results showed that surface modification by chitosan inhibits protein and bacterial deposition on the contact lens. Protein absorption analysis revealed that neat PHEMA adsorbed tear proteins at a density of 28.4 ± 4.4 μg/cm2, whereas the chitosan‐conjugated hydrogel adsorbed tear proteins at a density of 18.5 ± 1.8 μg/cm2. Moreover, the neat PHEMA bacterial adhesion had a mean CFU value of 273 ± 27. However, a significant decrease in the number of bacterial colonies was observed in the chitosan group with a CFU value of 9 ± 6. 相似文献
670.
Chen Tan Michelle C. Lee Mohammad Arshadi Morteza Azizi Alireza Abbaspourrad 《Angewandte Chemie (International ed. in English)》2020,59(24):9506-9513
Processing metal–organic frameworks (MOFs) into hierarchical macroscopic materials can greatly extend their practical applications. However, current strategies suffer from severe aggregation of MOFs and limited tuning of the hierarchical porous network. Now, a strategy is presented that can simultaneously tune the MOF loading, composition, spatial distribution, and confinement within various bio‐originated macroscopic supports, as well as control the accessibility, robustness, and formability of the support itself. This method enables the good dispersion of individual MOF nanoparticles on a spiderweb‐like network within each macrovoid even at high loadings (up to 86 wt %), ensuring the foam pores are highly accessible for excellent adsorption and catalytic capacity. Additionally, this approach allows the direct pre‐incorporation of other functional components into the framework. This strategy provides precise control over the properties of both the hierarchical support and MOF. 相似文献