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91.
Zhang LangTing Duan YaJuan Crespo Daniel Pineda Eloi Wang YunJiang Pelletier Jean-Marc Qiao JiChao 《中国科学:物理学 力学 天文学(英文版)》2021,64(9):1-10
Spatial frequency shift(SFS) microscopy with evanescent wave illumination shows intriguing advantages, including large field of view(FOV), high speed, and good modularity. However, a missing band in the spatial frequency domain hampers the SFS superresolution microscopy from achieving resolution better than 3 folds of the Abbe diffraction limit. Here, we propose a novel tunable large-SFS microscopy, making the resolution improvement of a linear system no longer restricted by the detection numerical aperture(NA). The complete wide-range detection in the spatial frequency domain is realized by tuning the illumination spatial frequency actively and broadly through an angle modulation between the azimuthal propagating directions of two evanescent waves. The vertical spatial frequency is tuned via a sectional saturation effect, and the reconstructed depth information can be added to the lateral superresolution mask for 3D imaging. A lateral resolution of λ/9, and a vertical localization precision of ~λ/200(detection objective NA = 0.9) are realized with a gallium phosphide(GaP) waveguide. Its unlimited resolution enhancing capability is demonstrated by introducing a designed metamaterial chip with an unusual large refractive index. Besides the great resolution enhancement, this method shows better anti-noise capability than classical structured illumination microscopy without SFS tunability. This method is chip-compatible and can potentially provide a massproducible illumination chip module achieving the fast, large-FOV, and deep-subwavelength 3D nanoscopy. 相似文献
92.
Shafia Shafiq Ronok Zahan Samina Yesmin Alam Khan Md. Sabbir Mahmud Md Abu Reza Sarah M. Albogami Mohammed Alorabi Michel De Waard Hebatallah M. Saad Jean-Marc Sabatier Tarannum Naz Gaber El-Saber Batiha 《Molecules (Basel, Switzerland)》2022,27(20)
Litsea glutinosa (L. glutinosa) is considered an evidence-based medicinal plant for the treatment of cancer, the leading cause of death worldwide. In our study, the in vitro antioxidant and in vivo anticancer properties of an essential ethno-medicinal plant, L. glutinosa, were examined using non-toxic doses and a phytochemical analysis was executed using gas-chromatography–mass-spectrometry. The in vitro antioxidant study of the L. glutinosa methanolic extract (LGBME) revealed a concentration-dependent antioxidant property. The bark extract showed promising antioxidant effects in the 2,2-diphenyl-1-picryl-hydrazyl (DPPH) assay. The strongest antioxidant activity was demonstrated at the maximum concentration (50 µg/mL). The IC50 values of the LGBME and BHT were 5.51 and 5.01 µg/mL, respectively. At the same concentration, the total antioxidant capacity of the LGBME was 0.161 µg/mL and the ferric reducing antioxidant power assay result of the LGBME was 1.783 µg/mL. In the cytotoxicity study, the LD50 of the LGBME and gallic acid were 24.93 µg/mL and 7.23 µg/mL, respectively. In the in vivo anticancer-activity studies, the LGBME, particularly at a dose of 150 mg/kg/bw, showed significant cell-growth inhibition, decreased tumor weight, increased mean survival rate, and upregulated the reduced hematological parameters in EAC (Ehrlich’s ascites carcinoma)-induced Swiss albino mice. The highest cell-growth inhibition, 85.76%, was observed with the dose of 150 mg/kg/bw. Furthermore, the upregulation of pro-apoptotic genes (p53, Bax) and the downregulation of anti-apoptotic Bcl-2 were observed. In conclusion, LGBME extract has several bioactive phytoconstituents, which confirms the antioxidant and anticancer properties of L. glutinosa. 相似文献
93.
Sorption thermodynamics of CO2, CH4, and their mixtures in the ITQ-1 zeolite as revealed by molecular simulations 总被引:1,自引:0,他引:1
Leyssale JM Papadopoulos GK Theodorou DN 《The journal of physical chemistry. B》2006,110(45):22742-22753
The thermodynamic properties and siting of carbon dioxide and methane sorbed in the siliceous form of zeolite MCM-22, ITQ-1, were studied by means of grand canonical Monte Carlo simulation. ITQ-1 comprises two independent pore systems of different geometry. It was found to be CO(2)-selective toward CO(2)/CH(4) gas mixtures, its equilibrium selectivity being distinctly higher in its sinusoidal channel pore system than in the large cavity system over a wide range of pressures starting from the Henry law regime, at the three temperatures considered. A maximum in selectivity is observed at low temperature, high pressure, and methane-rich gas-phase composition. 相似文献
94.
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97.
Dieter Seebach Jean-Marc Lapierre Wilfried Jaworek Paul Seiler 《Helvetica chimica acta》1993,76(1):459-475
The aldol adducts 1a – 13a of R,R-2(tertbutyl)-6-methyl-1,3-dioxan-4-one (from 3-hydroxybutanoic acid) to aldehydes, single diastereoisomers obtained as described previously, are acetylated or benzoylated to the corresponding esters 1b – 5b and 6c – 13c , respectively, which in turn are reduced with LiAlH4 to the title compounds 14 – 24 . The enantiomerically pure triols thus available may be useful as chiral building blocks, as auxiliaries for enantioselective reactions, and as center pieces for chiral dendrimers. 相似文献
98.
Jean-Marc Belley Michel Virgilio 《Journal of Mathematical Analysis and Applications》2005,306(2):646-662
Conditions are obtained for the Duffing equation with delay and state dependent impulses to admit a periodic solution. 相似文献
99.
100.
Jean-Marc Greneche 《Hyperfine Interactions》1998,111(1-4):261-268
We report first on the essential contributions of Mössbauer spectrometry to investigate iron-based metallic glasses. In addition to the analysis of the distributions of hyperfine data in terms of Fe coordination and neighbours, Mössbauer spectrometry is able to estimate the magnetic anisotropy from the magnetic texture, which can be correlated to the solidification process. After an overview of the different physical properties of the amorphous metallic alloys we also present their most advanced applications. 相似文献