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151.
In this study, nonlocal elasticity theory in conjunction with Gurtin–Murdoch elasticity theory is employed to investigate biaxial buckling and free vibration behavior of nanoplate made of functionally graded material (FGM) and resting on a visco-Pasternak standard linear solid-type of the foundation. The material characteristics of simply supported FGM nanoplates are assumed to be varied continuously as a power law function of the plate thickness. Hamilton’s principle is implemented to derive the non-classical governing equations of motion and related boundary conditions, which analytically solved to obtain the explicit closed-form expression for complex natural frequencies and buckling loads. Finally, attention is focused on considering the influences of various parameters on variation of damped natural frequency and buckling load ratio such as nonlocal parameter, surface effects, geometric parameters, power law index and properties of visco-Pasternak foundation and it is clearly demonstrated that these factors highly affect on vibration and buckling behavior. 相似文献
152.
Morteza Hosseini Freshteh Khaki Ehsan Shokri Hossein Khabbaz Mehdi Dadmehr Mohammad Reza Ganjali Mina Feizabadi Davood Ajloo 《Journal of fluorescence》2017,27(6):2059-2068
A novel sensitive method for detection of DNA methylation was developed with thioglycollic acid (TGA)-capped CdTe quantum dots (QDs) as fluorescence probes. Recognition of methylated DNA sites would be useful strategy due to the important roles of methylation in disease occurrence and developmental processes. DNA methylation occurs most often at cytosine-guanine sites (CpG dinucleotides) of gene promoters. The QDs significantly interacted with hybridized unmethylated and methylated DNA. The interaction of CpG rich methylated and unmethylated DNA hybrid with quantum dots as an optical probe has been investigated by fluorescence spectroscopy and electrophoresis assay. The fluorescence intensity of QDs was highly dependent to unmethylated and methylated DNA. Specific site of CpG islands of Adenomatous polyposis coli (APC), a well-studied tumor suppressor gene, was used as the detection target. Under optimum conditions, upon the addition of unmethylated dsDNA, the fluorescence intensity increased in linear range from 1.0?×?10??10 to 1.0?×?10??6M with detection limit of 6.2?×?10??11 M and on the other hand, the intensity of QDs showed no changes with addition of methylated dsDNA. We also demonstrated that the unmethylated and methylated DNA and QDs complexes showed different mobility in electrophoresis assay. This easy and reliable method could distinguish between methylated and unmethylated DNA sequences. 相似文献
153.
S. L. Chin H. L. Xu Q. Luo F. Théberge W. Liu J. F. Daigle Y. Kamali P. T. Simard J. Bernhardt S. A. Hosseini M. Sharifi G. Méjean A. Azarm C. Marceau O. Kosareva V. P. Kandidov N. Ak?zbek A. Becker G. Roy P. Mathieu J. R. Simard M. Chateauneuf J. Dubois 《Applied physics. B, Lasers and optics》2009,95(1):1-12
All matters in the path of filaments induced by an intense femtosecond laser pulse propagating in air could be fragmented
and result in the emission of characteristic fluorescence spectra from the excited fragments. The fluorescence spectra exhibit
specific signatures (fingerprints) that can be used for the identification of various substances including chemical and biological
species. In this paper, we present an overview of the recent progress in our laboratory concerning the “remote” sensing of
chemical and biological agents/pollutants in air using filamentation-induced nonlinear fluorescence techniques. 相似文献
154.
Ravi P. Agarwal Fatemah Mofarreh Rasool Shah Waewta Luangboon Kamsing Nonlaopon 《Entropy (Basel, Switzerland)》2021,23(8)
This research article is dedicated to solving fractional-order parabolic equations using an innovative analytical technique. The Adomian decomposition method is well supported by natural transform to establish closed form solutions for targeted problems. The procedure is simple, attractive and is preferred over other methods because it provides a closed form solution for the given problems. The solution graphs are plotted for both integer and fractional-order, which shows that the obtained results are in good contact with the exact solution of the problems. It is also observed that the solution of fractional-order problems are convergent to the solution of integer-order problem. In conclusion, the current technique is an accurate and straightforward approximate method that can be applied to solve other fractional-order partial differential equations. 相似文献
155.
Rahmat Sadeghi Rahim Hosseini 《Colloids and surfaces. A, Physicochemical and engineering aspects》2009,348(1-3):177-185
The volumetric, compressibility and electrical conductivity properties of sodium n-heptyl sulfonate (C7SO3Na) in pure water and in aqueous poly(ethylene glycol) (PEG) solutions were determined at different temperatures below and above the micellar composition range. At each temperature, the infinite dilution apparent molar volumes of the monomer and micellar state of C7SO3Na in aqueous PEG solutions respectively are smaller and larger than those in pure water. However, the values of the infinite dilution apparent molar isentropic compressibility of both monomer and micellar states of C7SO3Na in aqueous PEG solutions are larger than those in pure water. Thermodynamic parameters of micellization of investigated surfactant in water and in aqueous solutions of PEG at different temperatures were estimated and it was found that the micelle formation process is endothermic and therefore, this process must be driven by entropy increase. The calculated Gibbs free energies of micellization for aqueous PEG solutions are more negative than those for pure water and become more negative by increasing temperature. The variation of the critical micelle concentration (CMC) of C7SO3Na in water and in aqueous PEG solutions with temperature was obtained and a comparison between the CMC of C7SO3Na obtained from different thermodynamic properties was also made. 相似文献
156.
The design, synthesis, and characterization of the 10 linear and bent acentric ligands 1 – 10 (tectons) based on the differentiation of two divergently disposed coordinating poles is reported. The nature of the two poles and their distance are varied by the use of different linear spacers. For these molecules, a monodentate coordinating site, i.e., a pyridine ring, and a tridentate coordinating site, i.e., a pyridine moiety bearing at the 2 and 6 positions either two thioether groups or two dimethylamino units (PySMe and PyN(Me2)2 type, resp.), a terpyridine, or a pyridine ring bearing two optically pure dihydrooxazole units, are combined. 相似文献
157.
M.R. Ganjali B. Veismohammadi M. Hosseini P. Norouzi 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2009,74(2):575-578
A novel fluorescent chemosensor 2-(5-(dimethylamino)naphthalen-1-ylsulfonyl)-N-phenylhydrazinecarbothioamide (L) has been synthesized, which revealed an emission of 530 nm and when excited at 360 nm. The fluorescent probe undergoes a fluorescent emission intensity quenching upon binding to terbium ions in MeCN solution. The fluorescence quenching of L is attributed to the 1:1 complex formation between L and Tb(III) which has been utilized as the basis for the selective detection of Tb(III). The linear response range covers a concentration range of Tb(III) from 4.0 × 10−7 to 1.0 × 10−5 M and the detection limit is 1.4 × 10−7 M. The association constant of the 1:1 complex formation for L–Tb+3 was calculated to be 6.01 × 106 M−1, and the fluorescent probe exhibits high selectivity over other common metal ions mono-, di-, and trivalent cations indicate good selectivity for Tb(III) ions over a large number of interfering cations. 相似文献
158.
A. R. Moghadassi S. Masoud Hosseini D. Henneke A. Elkamel 《Journal of Thermal Analysis and Calorimetry》2009,96(1):81-84
Thermal conductivity is an important parameter in the field of nanofluid heat transfer. This article presents a novel model
for the prediction of the effective thermal conductivity of nanofluids based on dimensionless groups. The model expresses
the thermal conductivity of a nanofluid as a function of the thermal conductivity of the solid and liquid, their volume fractions,
particle size and interfacial shell properties. According to this model, thermal conductivity changes nonlinearly with nanoparticle
loading. The results are in good agreement with the experimental data of alumina-water and alumina-ethylene glycol based nanofluids. 相似文献
159.
M. Hosseini 《Journal of Mathematical Analysis and Applications》2009,357(1):314-1217
Let A and B be two Banach function algebras on locally compact Hausdorff spaces X and Y, respectively. Let T be a multiplicatively range-preserving map from A onto B in the sense that (TfTg)(Y)=(fg)(X) for all f,g∈A. We define equivalence relations on appropriate subsets and of X and Y, respectively, and show that T induces a homeomorphism between the quotient spaces of and by these equivalence relations. In particular, if all points in the Choquet boundaries of A and B are strong boundary points, then and are equal to the Choquet boundaries of A and B, respectively, and moreover, there exist a continuous function h on the Choquet boundary of B taking its values in {−1,1} and a homeomorphism φ from the Choquet boundary of B onto the Choquet boundary of A such that Tf(y)=h(y)f(φ(y)) for all f∈A and y in the Choquet boundary of B. For certain Banach function algebras A and B on compact Hausdorff spaces X and Y, respectively, we can weaken the surjectivity assumption and give a representation for maps belonging 2-locally to the family of all multiplicatively range-preserving maps from A onto B. 相似文献
160.
In this paper the category, C\mathcal{C} with respect to a certain class D\mathcal{D} of subobjects of C\mathcal{C} is formed and the universality of monomorphisms of ${\overset{\lower0.5em\hbox{${\overset{\lower0.5em\hbox{ is investigated. The main result characterizes ${\overset{\lower0.5em\hbox{${\overset{\lower0.5em\hbox{-universality of monos, in terms of C\mathcal{C}-universality of monos and the existence of local C\mathcal{C}-implications. 相似文献