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141.
Mohd-Ghazali Normah Estellé Patrice Halelfadl Salma Maré Thierry Siong Tng Choon Abidin Ummikalsom 《Journal of Thermal Analysis and Calorimetry》2019,136(2):937-941
Journal of Thermal Analysis and Calorimetry - The method of evaluating the magnetocaloric effect (MCE) and heat capacity of various magnetic samples from calorimetric experiments are presented.... 相似文献
142.
Patrice Cacciani 《Journal of Molecular Spectroscopy》2004,225(1):62-65
A tunable and narrowband vacuum ultraviolet laser system near λ=107.5 nm is used to record Doppler-free molecular beam spectra of the E1Π-X1Σ+ (0,0) band for three isotopomers of carbon monoxide. The Q branches of the E-X (0,0) bands in 12C16O, 13C16O, and 13C18O are fully resolved in this study, performed at a resolution of 0.02 cm−1 (FWHM). The newly obtained data are included in a comprehensive fitting routine with previous data to yield optimized molecular constants for the upper level. 相似文献
143.
Patrice de Meester Shirley S. C. Chu Misa V. Jovanovic Edward R. Biehl 《Journal of heterocyclic chemistry》1986,23(4):1131-1133
The X-ray crystal structure of 5-methyl-5,10-dihydrophenarsazine, C13H12NAs, has been determined. The crystals are orthorhombic, space group P212121, a = 8.511(4), b = 5.690(1), c = 23.535(9) Å, V = 1139.7(1.0)A3, and Z = 4. Least-squares refinement converged to R = 0.049 and Rw = 0.045. The central ring is in a boat conformation and the 5-methyl group is in the axial position with respect to the central ring. The folding angle between the planes of the two benzo rings is 154.1(4)°. 相似文献
144.
145.
Rousset N Keminon E Eléouet S Le Néel T Auget JL Vonarx V Carré J Lajat Y Patrice T 《Journal of photochemistry and photobiology. B, Biology》2000,56(2-3):118-131
Photodynamic therapy (PDT) with Photofrin has already been authorized for certain applications in Japan, the USA and France, and powerful second-generation sensitizers such as meta-(tetrahydroxyphenyl) chlorin (m-THPC) are now being considered for approval. Although sensitizers are likely to localize within the cytoplasm or the plasma membrane, nuclear membrane can be damaged at an early stage of photodynamic reaction, resulting in DNA lesions. Thus, it is of critical importance to assess the safety of m-THPC-PDT, which would be used mainly against early well-differentiated cancers. In this context, m-THPC toxicity and phototoxicity were studied by a colorimetric MTT assay on C6 cells to determine the LD50 (2.5 microg/ml m-THPC for 10 J/cm2 irradiation and 1 microg/ml for 25 J/cm2 irradiation) and PDT doses inducing around 25% cell death. Single-cell electrophoresis (a Comet assay with Tail Moment calculation) was used to evaluate DNA damage and repair in murine glioblastoma C6 cells after LD25 or higher doses for assays of PDT. These results were correlated with m-THPC nuclear distribution by confocal microspectrofluorimetry. m-THPC failed to induce significant changes in the Tail Moment of C6 cells in the absence of light, whereas m-THPC-PDT induced DNA damage immediately after irradiation. The Tail Moment increase was not linear (curve slope being 43 for 0-1 microg/ml m-THPC and 117 for 1-3 microg/ml), but the mean value increased with the light dose (0, 10 or 25 J/cm2) and incubation time (every hour from 1 to 4 h) for an incubation with m-THPC 1 microg/ml. However, cultured murine glioblastoma cells were capable of significant DNA repair after 4 h, and no residual DNA damage was evident after 24-h post-treatment incubation at 37 degrees C. An increase in the light dose appeared to be less genotoxic than an increase in the m-THPC dose for similar toxicities. Our results indicate that m-THPC PDT appears to be a safe treatment since DNA repair seemed to not be impaired and DNA damage occurred only with lethal PDT doses. However, the Comet assay cannot give us the certainty that no mutation, photoadducts or oxidative damage have been developed so this point would be verified with another mutagenicity assay. 相似文献
146.
Davide Beneventi Sabrine Alila Sami Boufi Didier Chaussy Patrice Nortier 《Cellulose (London, England)》2006,13(6):725-734
Polypyrrole was polymerized on the surface of cellulose fibres using a sequence of fibre impregnation in FeCl3 solutions, thickening and re-dispersion in a pyrrole solution. ζ-Potential and adsorption isotherms of the FeCl3-cellulose systems showed that the adsorption of iron III was associated with the formation of free Fe3+ cations in the impregnation liquor. Moreover, under the test conditions applied, the amount of adsorbed iron III was not sufficient to promote the polymerization of a adequate amount of pyrrole on the fibre surface. Optimization of the polymerization reaction required that the FeCl3 concentration in the impregnation liquor be increased to approximately 1 mol/l with a subsequent decrease of pH to approximately1.8. Based on scanning electron (SEM) micrographs and the low cellulose polymerization degree measured after pyrrole polymerization, we concluded that the decrease in the electric resistance of bulky polypyrrole/cellulose compounds was associated with a not negligible degradation of the cellulose fibres due to acid hydrolysis and the subsequent impossibility to prepare hand sheets with modified fibres due to the insufficient strength of the wet fibre network. The results of this investigation bring into question the use of FeCl3-pyrrole-cellulose systems for the elaboration of conducting paper sheets with good and stable mechanical properties. 相似文献
147.
Jana Sopkov‐de Oliveira Santos Pierre Verhaeghe Jean‐Franois Lohier Pascal Rathelot Patrice Vanelle Sylvain Rault 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(11):o643-o645
The crystal structures of closely related quinoline compounds substituted at the 2‐position by a vinyl group, either including a Cl atom [2‐(1‐chloro‐2‐methylprop‐1‐enyl)‐8‐nitroquinoline, C13H11ClN2O2, (I)] or not [2‐(2‐methylprop‐1‐enyl)‐8‐nitroquinoline, C13H12N2O2, (II)], show an important deviation of the vinyl group from coplanarity with the quinoline ring system if the Cl atom is present. The nitro group is perpendicular [in (II)] or nearly so [in (I)] to the quinoline ring system. In (II), all non‐H atoms except the nitro O atoms are located on a crystallographic mirror plane. 相似文献
148.
We give a detailed proof, under slightly weaker conditions on the objective function, that a modified Frank-Wolfe algorithm based on Wolfe's away step strategy can achieve geometric convergence, provided a strict complementarity assumption holds.Research supported by FCAC (Québec) and NSERC (Canada). 相似文献
149.
Patrice Le Calvez 《Communications in Mathematical Physics》1986,106(3):383-394
For each number between the lower and the upper rotation number of the Birkhoff attractor of a dissipative monotone twist map, there is a periodic or quasi-periodic orbit with rotation number . 相似文献
150.
Anne Giordani Patrice Morlière Mojgan Djavaheri-Mergny René Santus 《Photochemistry and photobiology》1998,68(3):309-313
The aconitase activity of the cytoplasmic iron regulatory protein-1 of NCTC 2544 keratinocytes is effectively inhibited by physiological doses of UVA. The time course of the photoinactivation is biphasic. A fast step is first observed corresponding to about 50% inactivation after exposure to 5 J/cm2of UVA followed by a much slower photoinactivation at higher doses. The water-soluble antioxidant N-acetylcysteine only partially inhibits the pho-toinduced inactivation of the cytoplasmic aconitase function, whereas the lipophilic vitamin E, the iron chelator, desferrioxamine and the superoxide dismutase inhibitor, diethyldithiocarbamate do not protect at all. As a consequence, reactive oxygen species such as O2-, H2O2 and lipid peroxides and hydroperoxides seem to play a rather minor role in the inactivation induced by the UVA pho-tooxidative stress although an oxidative stress produced by O2- H2O2 is known to inhibit reversibly and effectively cytoplasmic aconitase activity in mammalian cells. 相似文献