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排序方式: 共有235条查询结果,搜索用时 31 毫秒
1.
Yersak Thomas A. Hao Fang Kang Chansoon Salvador James R. Zhang Qinglin Malabet Hernando Jesus Gonzalez Cai Mei 《Journal of Solid State Electrochemistry》2022,26(3):709-718
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
2.
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
3.
4.
V.M. Prida V. VegaJ. García L. GonzálezW.O. Rosa A. FernándezB. Hernando 《Journal of magnetism and magnetic materials》2012
In this work, we highlight our recent progress in the synthesis and characterization of functional nanomaterials based on Fe–Pd ferromagnetic alloys by means of template-assisted deposition techniques employing highly ordered nanoporous alumina membranes, such as ordered arrays of nanowires and antidots thin films. Special attention is paid on their basic magnetic properties, such as coercivity, remanence and magnetic anisotropy, and their dependence on the microstructure and morphological parameters of the ordered arrays. 相似文献
5.
Hernando Quevedo 《General Relativity and Gravitation》2011,43(4):1141-1152
We present the Ernst potential and the line element of an exact solution of Einstein’s vacuum field equations that contains
as arbitrary parameters the total mass, the angular momentum, and the quadrupole moment of a rotating mass distribution. We
show that in the limiting case of slowly rotating and slightly deformed configuration, there exists a coordinate transformation
that relates the exact solution with the approximate Hartle solution. It is shown that this approximate solution can be smoothly
matched with an interior perfect fluid solution with physically reasonable properties. This opens the possibility of considering
the quadrupole moment as an additional physical degree of freedom that could be used to search for a realistic exact solution,
representing both the interior and exterior gravitational field generated by a self-gravitating axisymmetric distribution
of mass of perfect fluid in stationary rotation. 相似文献
6.
7.
Laura Parejo Dr. Mahdi Chaari Sara Santiago Dr. Gonzalo Guirado Prof. Francesc Teixidor Dr. Rosario Núñez Dr. Jordi Hernando 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(1):270-280
Icosahedral metallacarboranes are θ-shaped anionic molecules in which two icosahedra share one vertex that is a metal center. The most remarkable of these compounds is the anionic cobalt-based metallacarborane [Co(C2B9H11)2]−, whose oxidation-reduction processes occur via an outer sphere electron process. This, along with its low density negative charge, makes [Co(C2B9H11)2]− very appealing to participate in electron-transfer processes. In this work, [Co(C2B9H11)2]− is tethered to a perylenediimide dye to produce the first examples of switchable luminescent molecules and materials based on metallacarboranes. In particular, the electronic communication of [Co(C2B9H11)2]− with the appended chromophore unit in these compounds can be regulated upon application of redox stimuli, which allows the reversible modulation of the emitted fluorescence. As such, they behave as electrochemically-controlled fluorescent molecular switches in solution, which surpass the performance of previous systems based on conjugates of perylendiimides with ferrocene. Remarkably, they can form gels by treatment with appropriate mixtures of organic solvents, which result from the self-assembly of the cobaltabisdicarbollide-perylendiimide conjugates into 1D nanostructures. The interplay between dye π-stacking and metallacarborane electronic and steric interactions ultimately governs the supramolecular arrangement in these materials, which for one of the compounds prepared allows preserving the luminescent behavior in the gel state. 相似文献
8.
A. Uclés M. M. Ulaszewska M. D. Hernando M. J. Ramos S. Herrera E. García A. R. Fernández-Alba 《Analytical and bioanalytical chemistry》2013,405(18):5901-5914
This work introduces a liquid chromatography–electrospray ionization-hybrid quadrupole/time-of-flight mass spectrometry (LC-ESI-QTOF-MS)-based method for qualitative and quantitative analysis of poly(amidoamine) (PAMAM) dendrimers of generations 0 to 3 in an aqueous matrix. The multiple charging of PAMAM dendrimers generated by means of ESI has provided key advantages in dendrimer identification by assignation of charge state through high resolution of isotopic clusters. Isotopic distribution in function of abundance of isotopes 12C and 13C yielded valuable and complementarity data for confident characterization. A mass accuracy below 3.8 ppm for the most abundant isotopes (diagnostic ions) provided unambiguous identification of PAMAM dendrimers. Validation of the LC-ESI-QTOF-MS method and matrix effect evaluation enabled reliable and reproducible quantification. The validation parameters, limits of quantification in the range of 0.012 to 1.73 μM, depending on the generation, good linear range (R?>?0.996), repeatability (RSD?<?13.4 %), and reproducibility (RSD?<?10.9 %) demonstrated the suitability of the method for the quantification of dendrimers in aqueous matrices (water and wastewater). The added selectivity, achieved by multicharge phenomena, represents a clear advantage in screening aqueous mixtures due to the fact that the matrix had no significant effect on ionization, with what is evidenced by an absence of sensitivity loss in most generations of PAMAM dendrimers. Fig
Liquid chromatography–electrospray ionization-hybrid quadrupole/time of flight mass spectrometry (LC-ESI-QTOF-MS) based method for qualitative and quantitative analysis of PAMAM dendrimers in aqueous matrix 相似文献
9.
R. Coll L. Escoda J. Saurina J. L. Sánchez-Llamazares B. Hernando J. J. Suñol 《Journal of Thermal Analysis and Calorimetry》2010,99(3):905-909
Three magnetic shape memory alloys: Mn50Ni50−x
Sn
x
(x = 5, 7.5, and 10) were produced as bulk polycrystalline ingots by arc melting. The structural austenite–martensite transformation
was checked by calorimetry. The transformation temperatures decrease as increasing the Sn content. The same trend is found
in the entropy and enthalpy changes related to the transformation. The control of the valence electron by atom e/a determines the transformation temperatures range in this kind of alloys and it is possible to develop alloys that can be
candidates in applications as sensors and actuators. Furthermore, X-ray diffraction was performed to check the crystalline
structure at room temperature. 相似文献
10.
We investigate null and time-like geodesics in the Erez-Rosen space-time, that is, in the exterior gravitational field of a mass with quadrupole moment. By using the weak-field approximation of the Erez-Rosen metric, we find the solution of the equation for equatorial time-like geodesics and determine how they differ from the corresponding Schwarzschild geodesies. For the exact form of the Erez-Rosen metric, we only draw some qualitative conclusions about the influence of the quadrupole moment on the path of test particles and on the motion of photons. We derive the relativistic contribution of the quadrupole moment to the perihelion shift and to the precession of the ascending node. 相似文献