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1.
Peter Schmitt 《Geometriae Dedicata》1986,21(2):123-144
Summary For every k2 and r1 there exists a set of k prototiles that admits exactly r distinct tilings. All the tilings obtained are periodic. 相似文献
2.
Frédérique-Marie Rattis Josette Péguet-Navarro Pascal Courtellemont Gérard Redziniak Daniel Schmitt 《Photochemistry and photobiology》1995,62(5):914-916
Abstract— -Urocanic acid (UCA) represents the major ultraviolet B (UVB, 290–320 nm)-absorbing component of the skin. Trans-UCA is naturally produced in the stratum corneum and converts to the cis isomer upon UVB irradiation. In this study, we examined the effect of purified cis -UCA (about 99% of cis isomer) on the human Langerhans cell (LC) allostimulatory function by using the mixed epidermal cell-lymphocyte reaction (MELR). We found that addition of increasing amounts (6.5–400 μg/mL) of purified cis-UCA or (rara-UCA did not modify the T-cell response supported by enriched LC (eLC: 8–25% LC) as well as purified LC (pLC: 70–90% LC) suspensions. Because cis-UCA had no effect on the allostimulatory function of untreated LC, we investigated whether this compound could modify T-cell proliferation induced by UVB-irradiated LC. The UVB exposure of eLC or pLC to 100 J/m2 significantly inhibited the capacity of both suspensions to mount a T-cell response. However, addition of cis- UCA did not potentiate this UVB-induced immunosuppression. The eLC or pLC were then incubated with cis-UCA for 18 h at 37°C and washed before adding to allogeneic T cells. The obtained proliferative response was similar to that induced by control LC incubated in medium alone, demonstrating that pretreatment with cis -UCA did not alter human LC function. In conclusion, these results strongly suggest that cis-UCA has no direct effect on human LC antigen-presenting function. 相似文献
3.
4.
Acrylonitrole can be grafted in the bulk of PTFE films provided the monomer is allowed to diffuse into the grafted zones. For a given radiation dose, the amount of grafting is higher the lower the dose-rate. Even higher grafting efficiencies are reached under conditions of discontinuous irradiations, the reacting mixture being stored in the dark in a thermostat between successive irradiations. The grafting yield is higher the higher the storage temperature. The bulk grafting involves a progressive swelling of the grafted polyacrylonitrile branches by acrylonitrile monomer via a dipole-dipole association of the -CN groups of the monomer with the -CN groups in the polymer. 相似文献
5.
The elements are separated from iron by solvent-extraction. Cr, V and Mn are separated by ion-exchange chromatography with a strong acidic cation-exchanger. The elements are determined by 14 MeV-neutron activation analysis using γ-spectroscopy. The method is suitable for a concentration range of 0.05 to 5%. 相似文献
6.
7.
Karl Pays Caroline Mabille Véronique Schmitt Fernando Leal-Calderon J´erôme Bibette 《Journal of Dispersion Science and Technology》2013,34(1-3):175-186
This paper aims to review the various degradation pathays of emulsions. Aging of emulsions may proceed through three distinct microscopic mechanisms: diffusion or permeation, dewetting, and coalescence, each one being associated with a very characteristic growth scenario. We show within this context how double emulsions are a unique tool to complete the basic understanding of emulsion metastability. 相似文献
8.
Multimode pumped continuous-wave solid-state Raman laser 总被引:6,自引:0,他引:6
Grabtchikov AS Lisinetskii VA Orlovich VA Schmitt M Maksimenka R Kiefer W 《Optics letters》2004,29(21):2524-2526
We demonstrate the continuous-wave operation of a solid-state Raman laser containing a barium nitrate crystal as the Raman medium. The Raman laser, which has a singly resonant cavity, is pumped by multimode radiation. The Raman oscillation threshold is reached at approximately 2 W of pump power. As much as 500 kW/cm2 of Stokes power density at 60-kW/cm2 pump power density is obtained in the cavity. 相似文献
9.
F. G. Schmitt P. Chainais 《The European Physical Journal B - Condensed Matter and Complex Systems》2007,58(2):149-158
We reformulate various versions of infinitely divisible cascades proposed in the literature using stochastic equations. This
approach sheds a new light on the differences and common points of several formulations that have been recently provided by
several teams. In particular, we focus on the simplification occurring when the infinitely divisible noise at the heart of
such model is stable: an independently scattered random measure becomes a stable stochastic integral. In the last section
we discuss the D-dimensional generalization. 相似文献
10.
Owing to their mesoscopic length scales, colloidal suspensions provide ideal model systems suitable for addressing many problems in the field of statistical physics. Exemplarily, we highlight the versatile nature of such systems by discussing experiments with stochastic resonance and a practical realization of a recently proposed ratchet cellular automaton. 相似文献