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81.
A new higher order theory based analytical solution to the static analysis of general cross-ply plates is presented. The boundary-discontinuous generalized double Fourier series approach is used to solve highly coupled linear partial differential equations with the mixed type simply supported boundary conditions prescribed on the edges. The present results will provide data for the unsolved boundary conditions and provide benchmark comparisons for early design stages and verifications of numerical results such as finite element and boundary element. Analytical results are compared with finite element counterparts using commercially available software under uniformly distributed load. Present results are in good agreement with the finite element counterparts. The effects of important parameters such as lamination scheme, material property, thickness effects as well as their interactions are investigated in detail. 相似文献
82.
Dr. Sinan Wang Dr. David E. Korenchan Paola M. Perez Dr. Céline Taglang Dr. Thomas R. Hayes Dr. Renuka Sriram Dr. Robert Bok Andrew S. Hong Yunkou Wu Henry Li Prof. Zhen Wang Prof. John Kurhanewicz Prof. David M. Wilson Prof. Robert R. Flavell 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(51):11842-11846
Alterations in Zn2+ concentration are seen in normal tissues and in disease states, and for this reason imaging of Zn2+ is an area of active investigation. Herein, enriched [1-13C]cysteine and [1-13C2]iminodiacetic acid were developed as Zn2+-specific imaging probes using hyperpolarized 13C magnetic resonance spectroscopy. [1-13C]cysteine was used to accurately quantify Zn2+ in complex biological mixtures. These sensors can be employed to detect Zn2+ via imaging mechanisms including changes in 13C chemical shift, resonance linewidth, or T1. 相似文献
83.
Sinan M Panda M Ghosh A Dhara K Fanwick PE Chattopadhyay DJ Goswami S 《Journal of the American Chemical Society》2008,130(15):5185-5193
An efficient synthesis of a family of heteroaromatic triazinium compounds, [2a]X-[2g]X (X = Cl, ClO4, NO3, and HSO4), from 2-(arylazo)pyridines via proton-catalyzed heterocyclization is described. Characterization of the compounds is made by different spectroscopic, electrochemical techniques, as well as single-crystal structure determination of the triflate salt of a representative compound, [2a]CF3SO3. The bond parameters indicate that the tricyclo compound, 2a(+), is planar and aromatic with a N-N bond length of 1.275(6) A. These exhibited fluorescence with an emission maximum in the range of 540-535 nm with moderate quantum yields. The triazinium salts can be reduced in two successive one-electron steps as probed by cyclic voltammetry and coulometry. The paramagnetic radical intermediate 2a(*) is distinguished by a sharp and intense EPR spectrum. Fluorescence spectroscopy, circular dichroism, cyclic voltammetry, viscosity measurements, together with DNA melting studies have been used to characterize the binding of 2a(+) with calf thymus DNA. The emission quenching of the compound by [Fe(CN)6](4-) decreased when bound to DNA. As determined by a MTT assay, 2a(+) exhibited significant cytotoxicity at a higher concentration range of 1 mg/mL to 1 microg/mL; however, the % survival ratio increased with dilution. Cellular uptake studies of the referenced compound were followed by FACS analysis. 相似文献
84.
Sinan Ünver 《manuscripta mathematica》2016,149(3-4):405-441
In this paper we compute the values of the p-adic multiple polylogarithms of depth two at roots of unity. Our method is to solve the fundamental differential equation satisfied by the crystalline frobenius morphism using rigid analytic methods. The main result could be thought of as a computation in the p-adic theory of higher cyclotomy. We expect the result to be useful in proving non-vanishing results since it gives quite explicit formulas. 相似文献
85.
Keskin SS Aslan N Bayrakçeken F 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2007,67(3-4):762-766
X-ray, ultraviolet, and visible light induced photophysical changes of coumarin-540A in ethanol have been studied by the joint applications of X-ray, ultraviolet, and visible spectroscopy. Some impurities were found by X-ray fluorescence measurements. During the high power optical pumping, coumarin showed photochemical changes. Photoproduct emission spectra characteristics showed that photoproduct molecules can also be used as a laser dye at a different emission frequency in the ultraviolet region. 相似文献
86.
Sinan Ünver 《Journal of Number Theory》2011,131(8):1530-1546
In this paper, we study the Bloch group B2(F2[ε]) over the ring of dual numbers of the algebraic closure of the field with p elements, for a prime p?5. We show that a slight modification of Kontsevich?s -logarithm defines a function on B2(F2[ε]). Using this function and the characteristic p version of the additive dilogarithm function that we previously defined, we determine the structure of the infinitesimal part of B2(F2[ε]) completely. This enables us to define invariants on the group of deformations of Aomoto dilogarithms and determine its structure. This final result might be viewed as the analog of Hilbert?s third problem in characteristic p. 相似文献
87.
In 1990 Hilger defined the Time Scale Calculus which is the unification of discrete and continuous analysis in his PhD. In 2005 Yantir and Ufuktepe showed delta derivative with Mathematica[5]. In this study we give many computations of Time Scale Calculus with Mathematica such as the numerical and symbolic computation of forward jump operator and delta derivative for a particular time scale, graphs of functions, and definite integral on a time scale. We also improve and extent the Time Scale package for symbolics computations. 相似文献
88.
89.
A low-cost adsorbent and environmentally friendly adsorbent from Carpobrotus edulis plant was used for the removal of NO(3)(-), H(2)PO(4)(-), Pb(2+) and Cd(2+) ions from single, binary and multi-component systems. The efficiency of the adsorbent was studied using batch adsorption technique under different experimental conditions by varying parameters such as pH, initial concentration and contact time. In single component systems, the dried C. edulis has the highest affinity for Pb(2+), followed by NO(3)(-), Cd(2+) and H(2)PO(4)(-), with adsorption capacities of 175mg/g, 125mg/g, 28mg/g and 26mg/g, respectively. These results showed that the adsorption of NO(3)(-) and H(2)PO(4)(-) ions from single and binary component systems can be successfully described by Langmuir and Freundlich isotherms. Freundlich adsorption model, showed the best fit to the single and binary experimental adsorption data. These results also indicated that the adsorption yield of Pb(2+) ion was reduced by the presence of Cd(2+) ion in binary metal mixture. The competitive adsorption of NO(3)(-), H(2)PO(4)(-), Pb(2+) and Cd(2+) ions on dried C. edulis plant shows that NO(3)(-) and H(2)PO(4)(-) anions are able to adsorb on different free binding sites and Pb(2+) and Cd(2+) cations are able to adsorb on the same active sites of C. edulis particles. The dried C. edulis was found to be efficient in removing nitrate, phosphate, cadmium and lead from aqueous solution as compared to other adsorbents already used for the removal of these ions. 相似文献
90.
A comprehensive library of N- or 1-substituted indoles was formed by conjugate additions of indoline with Michael acceptors followed by an oxidation step. Using N-substituted indoles as key Michael donors, the synthesis of 1,3-disubstituted indoles was also accomplished. 相似文献