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311.
Michel Talagrand 《Mathematische Annalen》1979,240(2):97-102
Resumé On construit un groupe compact et une sous-mesure pathologique sur ce groupe dont la convolée avec la mesure de Haar n'est pas pathologique. 相似文献
312.
P. Franc J. Křemének Š. Piskoř W. Schäferlingová 《Czechoslovak Journal of Physics》1979,29(10):1084-1090
A multi-angle magnetic spectrograph for recording spectra of charged particles emitted in nuclear reactions has been built. The apparatus and the beam transport system are described and their parameters are discussed. 相似文献
313.
Gérard G. Emch 《Communications in Mathematical Physics》1976,49(3):191-215
The classical concept ofK-flow is generalized to cover situations encountered in non-equilibrium quantum statistical mechanics. The ergodic properties of generalizedK-flows are discussed. Several non-isomorphic examples are constructed, which differ already in the type (II1, III, and III1) of the factor on which they are defined. In particular, generalized factorK-flows with dynamical entropy either zero (singularK-flows) or infinite (special non-abelianK-flows) are constructed.On leave of absence from the Depts. of Mathematics and Physics, The University of Rochester, Rochester, N. Y. 14627, USA 相似文献
314.
I. Tserruya R. Schulé H. Schmidt-B?cking K. Bethge 《Zeitschrift für Physik A Hadrons and Nuclei》1976,89(1):233-241
TheK-shell ionization cross sections of Mn, Ni, Cu, Zn and Ge under32S bombardment have been measured in the energy range from 5 to 48 MeV. The cross sections are compared with available theories based on a direct Coulomb ionization mechanism and with the predictions of theK-vacancy sharing process. This last process can reasonably account for the measured cross sections at high bombarding energies. The energy shifts of theK
- andK
-lines and theK
/K
-intensity ratios have also been measured. This information is used to deduce the defect configuration of the atoms. The mechanisms responsible for the multiple vacancy production are discussed. 相似文献
315.
Kanemichi Muraoka Miharu Eguchi Osamu Ishitani Francois Chevire Kazuhiko Maeda 《Journal of Energy Chemistry》2021,(4):176-182
Hybrid materials constructed from a visible-light-absorbing semiconductor and a functional metal complex have attracted attention as efficient photocatalysts for CO2 reduction with high selectivity to a desired product.In this work,defect fluorite-type Ln-Ta oxynitrides LnTaOxNy(Ln=Nd,Sm,Gd,Tb,Dy and Ho)were examined as the semiconductor component in a hybrid photocatalyst system combined with known Ag nanoparticle promoter and binuclear ruthenium(Ⅱ)complex(RuRu’).Among the LnTaOxNy examined,TbTaOxNy gave the highest performance for CO2 reduction under visible light(k>400 nm),with a Ru Ru0-based turnover number of 18 and high selectivity to formate(>99%).Physicochemical analyses indicated that high crystallinity and more negative conduction band potential of Ln Ta OxNywith the absence of Ln-4 f states in the band gap structure contributed to higher activity of the hybrid photocatalyst. 相似文献
316.
Quentin Coquerel Claire Legendre Jacinthe Frangieh Stephan De Waard Jrme Montnach Leos Cmarko Joseph Khoury Charifat Said Hassane Dimitri Brard Benjamin Siegler Ziad Fajloun Harold De Pomyers Kamel Mabrouk Norbert Weiss Daniel Henrion Pascal Richomme Csar Mattei Michel De Waard Anne-Marie Le Ray Christian Legros 《Molecules (Basel, Switzerland)》2022,27(13)
Voltage-gated Na+ (NaV) channels are significant therapeutic targets for the treatment of cardiac and neurological disorders, thus promoting the search for novel NaV channel ligands. With the objective of discovering new blockers of NaV channel ligands, we screened an In-House vegetal alkaloid library using fluorescence cell-based assays. We screened 62 isoquinoline alkaloids (IA) for their ability to decrease the FRET signal of voltage sensor probes (VSP), which were induced by the activation of NaV channels with batrachotoxin (BTX) in GH3b6 cells. This led to the selection of five IA: liriodenine, oxostephanine, thalmiculine, protopine, and bebeerine, inhibiting the BTX-induced VSP signal with micromolar IC50. These five alkaloids were then assayed using the Na+ fluorescent probe ANG-2 and the patch-clamp technique. Only oxostephanine and liriodenine were able to inhibit the BTX-induced ANG-2 signal in HEK293-hNaV1.3 cells. Indeed, liriodenine and oxostephanine decreased the effects of BTX on Na+ currents elicited by the hNaV1.3 channel, suggesting that conformation change induced by BTX binding could induce a bias in fluorescent assays. However, among the five IA selected in the VSP assay, only bebeerine exhibited strong inhibitory effects against Na+ currents elicited by the hNav1.2 and hNav1.6 channels, with IC50 values below 10 µM. So far, bebeerine is the first BBIQ to have been reported to block NaV channels, with promising therapeutical applications. 相似文献
317.
Ganjehi L Marchiano R Coulouvrat F Thomas JL 《The Journal of the Acoustical Society of America》2008,124(1):57-71
The influence of the planetary boundary layer on the sonic boom received at the ground level is known since the 1960s to be of major importance. Sonic boom propagation in a turbulent medium is characterized by an increase of the mean rise time and a huge variability. An experiment is conducted at a 1:100,000 scale in water to investigate ultrasonic shock wave interaction with a single heterogeneity. The experiment shows a very good scaling with sonic boom, concerning the size of the heterogeneities, the wave amplitude, and the rise time of the incident wave. The wave front folding associated with local focusing, and its link to the increase of the rise time, are evidenced by the experiment. The observed amplification of the peak pressure (by a factor up to 2), and increase of the rise time (by up to about one magnitude order), are in qualitative agreement with sonic boom observations. A nonlinear parabolic model is compared favorably to the experiment on axis, though the paraxial approximation turns out less precise off axis. Simulations are finally used to discriminate between nonlinear and linear propagations, showing nonlinearities affect mostly the higher harmonics that are in the audible range for sonic booms. 相似文献
318.
Abstract Three new homologous series of mesogens containing three rings in the main structure and a lateral aromatic branch have been synthesized. When the lateral aromatic branch is attached to the middle ring, monotropic phases are observed, and there is a strong tendency to form the smectic C phase. When the lateral aromatic branch is attached to an outer ring, the compounds possess purely enantiotropic nematic phases. The terminal alkoxy chain in the outer ring which has a lateral aromatic substituent can be replaced by a rigid group without disturbing the large nematic range. Selective introduction of a particular substitutent may be useful for the construction of devices possessing desirable characteristics such as non-linear optical properties. 相似文献
319.
J. Pérez M. Vandevyver H. Strzelecka M. Verber C. Jallabert A. Barraud 《Liquid crystals》2013,40(6):1627-1634
Abstract Langmuir-Blodgett films of a discotic mesogenic pyrylium tetrafluoroborate salt (1) have been investigated from the point of view of their in-plane anisotropy, i.e. considering the average molecular orientation with respect to the dipping direction. The molecules are found to stand on edge with their flat polycyclic core more or less perpendicular to the dipping direction. Mixing 1 with N(C4H9)4 + TCNQ? in the spreading solvent leads to a different behaviour of the monolayer at the air-water interface, involving the formation of the Pyrylium-TCNQ salt. In contrast to the films of pure 1, these films do not exhibit any in-plane anisotropy after deposition on a solid substrate. The temperature dependance of the molecular anisotropy of both films has also been investigated. The results are presented and discussed in the framework of their mesomorphic properties together with the influence of the anion associated with Pyrylium. 相似文献
320.
J. Lub Corresponding author V. Recaj L. Puig P. Forcén C. Luengo 《Liquid crystals》2013,40(12):1627-1637
The synthesis and photopolymerization of various liquid crystalline dioxetanes is described. The effects of the spacer length, structure of the mesogenic group and oxetane group on the liquid crystalline properties, polymerization behaviour and optical properties (birefringence) of the oriented and crosslinked network formed in photo-polymerization are discussed. Thermally stable films with birefringence values up to 0.13 can be formed from these materials. The dioxetanes show significantly lower polymerization shrinkage than do structurally related diacrylates. 相似文献