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41.
Journal of Solid State Electrochemistry - In this study, hot pressing was evaluated as a method of cell fabrication to increase the energy density of next-generation all-solid-state batteries with...  相似文献   
42.
We study isometric embeddings of a Euclidean space or a Heisenberg group into a higher dimensional Heisenberg group, where both the source and target space are equipped with an arbitrary left-invariant homogeneous distance that is not necessarily sub-Riemannian. We show that if all infinite geodesics in the target are straight lines, then such an embedding must be a homogeneous homomorphism. We discuss a necessary and certain sufficient conditions for the target space to have this ‘geodesic linearity property’, and we provide various examples.  相似文献   
43.
Music of the spheres : Infinite coordination polymerization of Zn2+ ions and a multitopic ligand produces metal–organic micro‐ and nanospheres that can be used as functional matrices. The spheres can encapsulate combinations of active substances, such as organic dyes, magnetic nanoparticles, or luminescent quantum dots (see image), which results in spheres that are luminescent in the blue, green, and red regions of the spectrum.

  相似文献   

44.
Horseradish peroxidase (HRP) has been immobilized on the surface of functionalized nanocrystalline diamond (NCD) thin films. The structure of the modified NCD surface as well as the electrochemical behavior of the whole system was characterized by impedance spectroscopy and cyclic voltammetry. The proximity of HRP heme groups to the NCD surface allowed direct electron transfer between them, resulting in two separated one-electron-transfer peaks at 0.05 V and 0.29 V vs Ag/AgCl, corresponding to the cathodic and anodic process, respectively. The heterogeneous electron-transfer constant for both processes was calculated to be 0.066 s(-1), the charge-transfer coefficient alpha = 0.49, and the immobilized enzymatic layer about 2.10(-10) mol/cm2. The modified NCD electrode was used as a third-generation biosensor for hydrogen peroxide determination showing a linear response in the 0.1-45 mM H2O2 range, at +0.05 V vs Ag/AgCl.  相似文献   
45.
In this note we characterize the one-generated subdirectly irreducible MV-algebras and use this characterization to prove that a quasivariety of MV-algebras has the relative congruence extension property if and only if it is a variety.  相似文献   
46.
We discuss the problem of motion of test particles in a monopolequadrupole gravitational field and compare the results presented in different publications.  相似文献   
47.
Nous étudions les champs tensoriels de type électromagnétique, qui sont des champs de type (1, 1) satisfaisant une condition polynomique avec des coefficients functions.  相似文献   
48.
The kinetics and mechanism of the reaction of complexation of chromium(III) with 2-acetyl-cyclohexanone has been investigated spectrophotometrically in aqueous solution at 50°C and ionic strength 0.5 mol dm?3 NaClO4. The equilibrium constants of the complex have been determined. The mechanism proposed to account for the kinetic data involves a double reversible pathway where both Cr3+ and Cr(OH)2+ react with the enol tautomer of the ligand with rate constants of 9.6 × 10?3 dm3 mol?1 s?1, and 3.69 × 10?2 dm3 mol?1 s?1, respectively. Some discussions are made on the basis of Eigen-Wilkins theory considering the effect of solvent exchange on the complex formation.  相似文献   
49.
5-Hydroxy-L-tryptophan 4 with potassium cyanate gives 5-(5-hydroxy-3-indolylmethyl)hydantoin 5 or Nb-carbamoyl-5-hydroxy-L-tryptophan 6 depending on the reaction conditions. Reaction of 4 with methyl iso-cyanate in acetone provides 5-hydroxy-Nb-methylcarbamoyl-L-tryptophan 7 . Treatment of 4 with ethyl, propyl and isopropyl isocyanates in acetone gives rise to the formation of the corresponding 2-[(3-alkyl-4,4-dimethyl-2-oxo)-1,3-diazetidinyl]-3-(5-hydroxy-3-indolyl)propionic acids 8–10 .  相似文献   
50.
Using the formalism of geometrothermodynamics, we investigate the geometric properties of the equilibrium manifold for diverse thermodynamic systems. Starting from Legendre invariant metrics of the phase manifold, we derive thermodynamic metrics for the equilibrium manifold whose curvature becomes singular at those points where phase transitions of first and second order occur. We conclude that the thermodynamic curvature of the equilibrium manifold, as defined in geometrothermodynamics, can be used as a measure of thermodynamic interaction in diverse systems with two and three thermodynamic degrees of freedom.  相似文献   
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