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71.
Guang‐Ri Xu Xin‐hua Qi Fengxia Yang Jae‐Joon Lee Ming‐Lu Xu Yu‐Ping Zhang Sunghyun Kim 《Electroanalysis》2009,21(22):2486-2490
A glassy carbon electrode having two polymer layers has been applied to selectively detect epinephrine. The inner layer formed by electropolymerization of macrocyclic nickel complex functioned as an electrocatalyst for epinephrine oxidation and the outer layer composed of hydrolyzed polyurethane γ‐benzyl L ‐glutamate as a screening layer. Differential pulse voltammetry showed almost 100% recovery of epinephrine even in 100‐fold excess of interferents. When applied to a dual glassy carbon electrode as an amperometric detector in flow injection analysis, a linear response over 0.1 μM and 10 μM was obtained. Recovery tested for 5‐fold diluted human urine samples was 97.5%. 相似文献
72.
In this paper we study the controllability of series connections of arbitrarily many linear systems. As the main result, we completely determine the controllability and the possible controllability indices of a system obtained by a special series connection of arbitrarily many linear systems. 相似文献
73.
D. D. Ri V. G. Mansurov A. Yu. Nikitin A. K. Gutakovskii K. S. Zhuravlev P. Tronc 《JETP Letters》2005,81(2):62-65
The photoluminescence (PL) of GaN quantum dots in an AlN matrix is studied. It is found that the maximum of the PL line does not shift when the laser excitation power varies. The transient PL spectra indicate that the quenching kinetics is nonexponential and the quenching law depends on the spectral range. The experimental data are explained in the framework of a model taking into account the strong built-in electric field in wurtzite structures and the transport of charge carriers between them. 相似文献
74.
Edward Furman Ri?ardas Zitikis 《Journal of Mathematical Analysis and Applications》2008,348(2):971-976
The gamma function and its various modifications such as the (upper) incomplete, regularized and inverted-regularized incomplete gamma functions are of importance in both theory and applications. In this note we observe an ‘if and only if ’ relationship between a certain axiom of insurance risk management and a monotonicity property of the composition of regularized and inverted-regularized incomplete gamma functions, assuming that the risks follow gamma distributions. We derive the monotonicity property by utilizing the above noted relationship and a probabilistic technique. The aforementioned insurance axiom, called consistent no-undercut, is explained in detail and related to several techniques of analysis. 相似文献
75.
We describe a wave-front displacement system using a novel configuration of a pair of wedge prisms. The wave-front propagation, through the displacement system, is analyzed using the exact ray trace. The main advantage, of this configuration, is that the shearing (direction and magnitude) is constant from the displacement system to the image plane. The direction of the shearing depends on the relative orientation of the prisms. The magnitude of the shearing is proportional to the distance between prisms. The proportionality constant depends on the wedge angle and the material of fabrication of the prisms, and it gives the sensitivity to the displacement of the system. The deviation of the shearing due to the difference between the wedge angles is larger than that the produced by the oblique incidence of the wave-front. The experimental results confirm the theoretical data. 相似文献
76.
A facile method for solid‐phase organic synthesis of 1‐substituted‐4‐vinyl‐1,2,3‐triazoles from polystyrene‐supported but‐3‐ynyl selenide has been developed. This sequential [3+2] cycloaddition and oxidation–elimination reactions could be carried out under mild reaction conditions with straightforward operation and good yield and purity of the products, and broad scope of substrates, and could be applied in this reaction system in generation of a small library of title compounds. 相似文献
77.
<正>A novel polyamide containing xanthene structure and trifluoromethylphenoxy pendent was prepared from 9,9-bis[4-(4- aminophenoxy)phenyl]xanthene,a novel diamine with 2-(4-trifluoromethylphenoxy)terephthaloyl chloride,by the low temperature polycondensation.This new polyamide with the inherent viscosity of 0.95 dL/g was amorphous and readily soluble in polar solvents such as DMAc,m-cresol,etc.This polyamide showed the glass transition temperature(T_g) of 236℃,decomposition temperature (Td) at 5%weight loss of 455℃and char yield of 56%at 800℃in N_2.Transparent,flexible,and tough film of the polymer cast from DMAc solution exhibited tensile strength of 93 MPa,elongation at break of 14%,initial moduli of 2.2 GPa.The electric properties such as the dielectric constant of 3.03(1 MHz) and surface resistance(2.78×10~(14)Ω),and the moisture uptake of 1.36% were also described. 相似文献
78.
Carlos Rodríguez-Abreu Margarita Sanchez-Domínguez Bojan Šarac Marija Bešter Rogač Rekha Goswami Shrestha Lok Kumar Shrestha Dharmesh Varade Goutam Ghosh Vinod K. Aswal 《Colloid and polymer science》2010,288(8):923-935
Mixtures of a hydrophobic triblock copolymer (L121, PEO5PPO68PEO5) and a hydrophobic anionic surfactant (AOT, Sodium bis(2-ethylhexyl)sulfosuccinate), each alone forming turbid vesicular
solutions in water, aggregate to produce a thermodynamically stable, transparent and isotropic solution. Mixed AOT/L121 aggregates
could be confirmed by fluorescence, surface tension, differential scanning calorimetry (DSC) and isothermal titration calorimetry
(ITC). In an isotropic region, where mixed aggregates are formed, there is a synergistic interaction between monomers of AOT
and L121 in the mixture. In addition, Small Angle Neutron Scattering (SANS) experiments provided evidence that mixed aggregates
have the shape of either spheres (with a certain polydispersity) or very short ellipsoids (axial ratio below 2), confirming
a transition from giant multilamellar vesicles to small aggregates upon mixing the two hydrophobic amphiphiles. Upon dilution,
the morphology changes to disk-like. From an examination of the results of all the methods the peculiar behavior of the mixed
AOT/L121 system is explained. 相似文献
79.
Martín Egozcue Luis Fuentes García Wing-Keung Wong Ričardas Zitikis 《Central European Journal of Mathematics》2011,9(6):1288-1297
We show that Grüss-type probabilistic inequalities for covariances can be considerably sharpened when the underlying random
variables are quadrant dependent in expectation (QDE). The herein established covariance bounds not only sharpen the classical
Grüss inequality but also improve upon recently derived Grüss-type bounds under the assumption of quadrant dependency (QD),
which is stronger than QDE. We illustrate our general results with examples based on specially devised bivariate distributions
that are QDE but not QD. Such results play important roles in decision making under uncertainty, and particularly in areas
such as economics, finance, and insurance. 相似文献
80.
Mainali L Raguz M Camenisch TG Hyde JS Subczynski WK 《Journal of magnetic resonance (San Diego, Calif. : 1997)》2011,212(1):86-94
Saturation-recovery (SR) EPR at W-band (94 GHz) to obtain profiles of the membrane fluidity and profiles of the oxygen transport parameter is demonstrated for lens lipid membranes using phosphatidylcholine (n-PC), stearic acid (n-SASL), and cholesterol analog (ASL and CSL) spin labels, and compared with results obtained in parallel experiments at X-band (9.4 GHz). Membranes were derived from the total lipids extracted from 2-year-old porcine lens cortex and nucleus. Two findings are especially significant. First, measurements of the spin-lattice relaxation times T1 for n-PCs allowed T1 profiles across the membrane to be obtained. These profiles reflect local membrane properties differently than profiles of the order parameter. Profiles obtained at W-band are, however, shifted to longer T1 values compared to those obtained at X-band. Second, using cholesterol analog spin labels and relaxation agents (hydrophobic oxygen and water-soluble NiEDDA), the cholesterol bilayer domain was discriminated in membranes made from lipids of the lens nucleus. However, membranes made from cortical lipids show a single homogeneous environment. Profiles of the oxygen transport parameter obtained from W-band measurements are practically identical to those obtained from X-band measurements, and are very similar to those obtained earlier at X-band for membranes made of 2-year-old bovine cortical and nuclear lens lipids (M. Raguz, J. Widomska, J. Dillon, E.R. Gaillard, W.K. Subczynski, Biochim. Biophys. Acta 1788 (2009) 2380-2388). Results demonstrate that SR EPR at W-band has the potential to be a powerful tool for studying samples of small volume, ~30 nL, compared with the sample volume of ~3 μL at X-band. 相似文献