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131.
P.V. Chliapnikov S.A. Gumenyuk A.M. Rubin O.G. Tchikilev A.P. Vorobjev E. de Wolf D.P. Johnson P. Peeters F. Verbeure F. Grard V.P. Henri P. Herquet J. Laurent J. Schlesinger R. Windmolders G. Ciapetti W. Dunwoodie Y. Goldschmidt-Clermont D.C. Watkins 《Nuclear Physics B》1976,105(3):510-526
The reaction K+p→Δ++(1236)+ anything is studied at beam momenta 8.2 and 16 GeV/c and compared with other Δ++ producing reactions. We find that the low-mass Δ++π? enhancement affects the shapes of Δ++ inclusive distributions. The triple-Regge formula is found to be consistent with the data. Dual properties of this formula are successfully tested. 相似文献
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134.
The response of a mesoscopic superconducting disk to perpendicular magnetic fields is studied by using the multiple-small-tunnel-junction method, in which transport properties of several small tunnel junctions attached to the disk are measured simultaneously. This allows us to make the first experimental distinction between the giant vortex states and multivortex states. Moreover, we experimentally find a magnetic-field induced rearrangement and combination of vortices. The experimental results are well reproduced in numerical results based on the nonlinear Ginzburg-Landau theory. 相似文献
135.
Angel Dago Morales Hctor Novoa de Armas Norbert M. Blaton Oswald M. Peeters Camiel J. De Ranter Heidy Mrquez Ramn Poms Hernndez 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(8):1042-1043
The title compound, C9H11NO3S, has crystallographic mirror symmetry, occurs in the thiocarbamate form and is stabilized in an s‐cisoid,s‐transoid conformation with respect to the C—N—C group. There are two intramolecular hydrogen bonds, one between the H atom of the N—H group and the O atom of the furan ring, and the other between the H atom of the secondary carbon of the isopropyl group and the S atom. The packing of the molecules is assumed to be dictated by van der Waals interactions. 相似文献
136.
Julio Duque Hctor Novoa de Armas Ramn Poms Hernndez Margarita Surez Navarro Estael Ochoa Rodríguez Esperanza Salfrn Yamila Verdecia Reyes Norbert. M Blaton Oswald M. Peeters Camiel J. De Ranter 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(11):1346-1347
In the title compound, C28H38N4O6, the 4‐aryl substituent occupies a pseudo‐axial position approximately orthogonal to the plane of the dihydropyridine ring [88.1 (3)°]. The dihydropyridine ring adopts a flattened boat conformation. The H atom on the pyridine N atom is involved in a bifurcated intramolecular hydrogen bond, the acceptors being the N atoms of the two piperidylmethyl groups [N?N 2.629 (4) and 2.695 (4) Å]. 相似文献
137.
Small gold clusters Au m (m????16) were analyzed step by step using the density functional theory at B3LYP level with a Lanl2DZ pseudopotential to understand the rules governing the structures obtained for the most stable clusters. After a characterization by means of the NBO population analysis and spin densities, the particular electronic structure of such species was confronted to their structural parameters and stability. It appears that the most stable structures can be described in an original way through resonance structures resulting from an analysis of Au m clusters into dimeric Au2 subunits. These are arranged so as to promote: 1. A good overlap between bonding ?? and anti-bonding ??* areas belonging to different Au2 units. 2. A cyclic flow of electrons over the whole cluster. This model uses relatively simple chemical concepts in order to justify most of the structures already found in the literature as well as to establish a new approach explaining the structural transition from two- to three-dimensional configurations. 相似文献
138.
J. Alenus A. Ethirajan F. Horemans A. Weustenraed P. Csipai J. Gruber M. Peeters T. J. Cleij P. Wagner 《Analytical and bioanalytical chemistry》2013,405(20):6479-6487
Molecularly imprinted polymers (MIPs) are synthetic receptors that are able to specifically bind their target molecules in complex samples, making them a versatile tool in biosensor technology. The combination of MIPs as a recognition element with quartz crystal microbalances (QCM-D with dissipation monitoring) gives a straightforward and sensitive device, which can simultaneously measure frequency and dissipation changes. In this work, bulk-polymerized l-nicotine MIPs were used to test the feasibility of l-nicotine detection in saliva and urine samples. First, l-nicotine-spiked saliva and urine were measured after dilution in demineralized water and 0.1× phosphate-buffered saline solution for proof-of-concept purposes. l-nicotine could indeed be detected specifically in the biologically relevant micromolar concentration range. After successfully testing on spiked samples, saliva was analyzed, which was collected during chewing of either nicotine tablets with different concentrations or of smokeless tobacco. The MIPs in combination with QCM-D were able to distinguish clearly between these samples: This proves the functioning of the concept with saliva, which mediates the oral uptake of nicotine as an alternative to the consumption of cigarettes. Figure
Schematics of the sample-preparation procedure for l-nicotine spiked saliva- and urine samples with various concentration levels 相似文献
139.
140.
M. Tadi V. Mlinar F.M. Peeters 《Physica E: Low-dimensional Systems and Nanostructures》2005,26(1-4):212
Exciton states in self-assembled InP/In0.49Ga0.51P quantum dots subject to magnetic fields up to 50 T are calculated. Strain and band mixing are explicitly taken into account in the single-particle models of the electronic structure, while an exact diagonalization approach is adopted to compute the exciton states. Reasonably good agreement with magneto-photoluminescence measurements on InP self-assembled quantum dots is found. As a result of the polarization and angular momentum sensitive selection rules, the exciton ground state is dark. For in-plane polarized light, the magnetic field barely affects the exciton spatial localization, and consequently the exciton oscillator strength for recombination increases only slightly with increasing field. For z polarized light, a sharp increase of the oscillator strength beyond 30 T is found which is attributed to the enhanced s character of the relevant portion of the exciton wave function. 相似文献