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181.
Areli A. Molina‐Paredes Víctor M. Jimnez‐Prez Jesús A. Lara‐Cern Ivana Moggio Eduardo Arias Rosa Santilln Mario Snchez Alma Saucedo‐Yaez Blanca M. Muoz‐Flores 《应用有机金属化学》2019,33(1)
Five novel organoboron complexes were synthesized in just 15 min via microware irradiation, by one pot multicomponent reactions between diverse aryl aldehydes with benzoylhydrazide, or 4‐nitrobenzoylhidrazine and diphenyl boronic acid, in a 1:1:1 ratio in benzene. The products were characterized by 1H, 13C, 11B NMR, UV, IR, spectroscopy and high‐resolution mass spectrometry (HRMS). The molecular structure was also determined by single‐crystal X‐ray diffraction for two complexes, which showed the tetra‐coordination of the boron atoms giving rise to distorted tetrahedral molecular geometry with a strong intermolecular C‐H···π interactions. In spite of the low quantum yields exhibited by the series in solution, some complexes stained uniformly the silk fibroins emitting enough fluorescence to allow its characterization by confocal microscopy. Boron as chelate center of the five complexes resulted not to be toxic for B16F10 cells, these compounds are appropriate for their used in medical applications. 相似文献
182.
Molina Higgins Maria C. Radcliffe Nicholus A. Toro-González Miguel Rojas Jessika V. 《Journal of Radioanalytical and Nuclear Chemistry》2019,322(2):707-716
Journal of Radioanalytical and Nuclear Chemistry - Composites containing WO3 or HfO2 nanoparticles were prepared and investigated as alternative shielding materials. Their performance was assessed... 相似文献
183.
We analyze the numerical representability of total preorders defined on semitopological real algebras through continuous order-preserving
real-valued functions that are also additive and multiplicative. The results obtained are used to interpret important concepts
arising in Social Choice theory. 相似文献
184.
185.
C. Genest J. J. Quesada Molina J. A. Rodríguez Lallena C. Sempi 《Journal of multivariate analysis》1999,69(2):193
The notion of quasi-copula was introduced by C. Alsina, R. B. Nelsen, and B. Schweizer (Statist. Probab. Lett.(1993), 85–89) and was used by these authors and others to characterize operations on distribution functions that can or cannot be derived from operations on random variables. In this paper, the concept of quasi-copula is characterized in simpler operational terms and the result is used to show that absolutely continuous quasi-copulas are not necessarily copulas, thereby answering in the negative an open question of the above mentioned authors. 相似文献
186.
In this work the feasibility of using Mg2SiO4:Tb as a fiberoptic radioluminescent (RL) dosimetry probe for real-time dosimetry has been investigated for the first time. In particular, the stability of the RL signal after repeated use, the spectrum of the RL emission and the dose-rate response curve of a Mg2SiO4:Tb-based fiberoptic probe have been determined. The probe has been also used to obtain a percentage dose depth curve in a water phantom and its performance has been compared to that of a standard ion chamber. Besides, its absolute RL yield has been compared to that of an RL probe based on the commercial Al2O3:C phosphor. 相似文献
187.
A general analytical expression has been deduced for the I/E response of the square wave voltammetry corresponding to ion transfer processes in systems with two liquid/liquid polarized interfaces. This expression has been evaluated through the experimental study of a series of quaternary ammonium cations and metal chloro complex anions. We have found that systems with two liquid/liquid polarizable interfaces present the striking advantage that the difference between peak potentials of square wave voltammograms of cations and anions with similar standard ion transfer potential is much greater than in systems with a single polarizable one. 相似文献
188.
Luis A. Montero Jos Molina Jürgen Fabian 《International journal of quantum chemistry》2000,79(1):8-16
Multiple minima of water cluster hypersurfaces are explored to find thermodynamic properties by means of the corresponding partition functions of their canonical distributions. The combination of semiempirical quantum chemical procedures for calculating the cluster energies in local minima of supermolecules and the statistical thermodynamics approach for both the evaluation of macroscopic association energies and the possible reduction by average of absolute errors intrinsic to the parametrized Hamiltonian are shown to provide an appropriate model for comparison between experimental and theoretical results. The method can explicitly take into account environmental effects due to intermolecular interaction. Water trimer and tetramer association energies of ?10.9 and ?14.1 kJ/mol obtained from virial coefficient calculations compare very well to the values of ?10.5 and ?16.4 kJ/mol, respectively, found for the theoretical association energies in this paper. © 2000 John Wiley & Sons, Inc. Int J Quant Chem 79: 8–16, 2000 相似文献
189.
We characterize the exchange property for non-unital rings in terms of their local rings at elements,and we use this characterization to show that the exchange property is Morita invariant for idempotent rings.We also prove that every ring contains a greatest exchange idela(with respect to the inclusion). 相似文献
190.
A notion of generalized inverse extending that of Moore—Penrose inverse for continuous linear operators between Hilbert spaces and that of group inverse for elements of an associative algebra is defined in any Jordan triple system (J, P). An element a?J has a (unique) generalized inverse if and only if it is strongly regular, i.e., a?P(a)2J. A Jordan triple system J is strongly regular if and only if it is von Neumann regular and has no nonzero nilpotent elements. Generalized inverses have properties similar to those of the invertible elements in unital Jordan algebras. With a suitable notion of strong associativity, for a strongly regular element a?J with generalized inverse b the subtriple generated by {a, b} is strongly associative 相似文献