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排序方式: 共有321条查询结果,搜索用时 31 毫秒
311.
Christelle Marminon 《Tetrahedron》2007,63(3):735-739
The benzylation of 4,7-dimethoxy-1H-indole (5) followed by an oxidative demethylation led to 1-benzyl-1H-indole-4,7-dione (2) with a 73% overall yield. From the commercially available 7-nitro-1H-indazole (7), a three-step pathway was developed to access 1-benzyl-1H-indazole-4,7-dione (3). Two of these steps were investigated in order to improve the process. The direct synthesis of 1-benzyl-1H-benzotriazole-4,7-dione (4), through a 1,3-dipolar cycloaddition between benzyl azide and para-benzoquinone (13), was also studied. The simplicity of the methodologies described offers wide perspectives in obtaining 1-alkylated indole-, indazole- and benzotriazole-4,7-diones. 相似文献
312.
Third-harmonic generation in slow-light chalcogenide glass photonic crystal waveguides 总被引:1,自引:0,他引:1
Monat C Spurny M Grillet C O'Faolain L Krauss TF Eggleton BJ Bulla D Madden S Luther-Davies B 《Optics letters》2011,36(15):2818-2820
We demonstrate third-harmonic generation (THG) in a dispersion-engineered slow-light photonic crystal waveguide fabricated in AMTIR-1 chalcogenide glass. Owing to the relatively low loss and low dispersion in the slow-light (c/30) regime, combined with the high nonlinear figure of merit of the material (~2), we obtain a relatively large conversion efficiency (1.4×10(-8)/W(2)), which is 30× higher than in comparable silicon waveguides, and observe a uniform visible light pattern along the waveguide. These results widen the number of applications underpinned by THG in slow-light platforms, such as the direct observation of the spatial evolution of the propagating mode. 相似文献
313.
Andrew D. Wiersum Estelle Soubeyrand‐Lenoir Dr. Qingyuan Yang Dr. Beatrice Moulin Vincent Guillerm Dr. Mouna Ben Yahia Dr. Sandrine Bourrelly Dr. Alexandre Vimont Dr. Stuart Miller Dr. Christelle Vagner Prof. Marco Daturi Dr. Guillaume Clet Dr. Christian Serre Dr. Guillaume Maurin Dr. Philip L. Llewellyn 《化学:亚洲杂志》2011,6(12):3270-3280
In addition to its high thermal stability, repetitive hydration/dehydration tests have revealed that the porous zirconium terephthalate UiO‐66 switches reversibly between its dehydroxylated and hydroxylated versions. The structure of its dehydroxylated form has thus been elucidated by coupling molecular simulations and X‐ray powder diffraction data. Infrared measurements have shown that relatively weak acid sites are available while microcalorimetry combined with Monte Carlo simulations emphasize moderate interactions between the UiO‐66 surface and a wide range of guest molecules including CH4, CO, and CO2. These properties, in conjunction with its significant adsorption capacity, make UiO‐66 of interest for its further evaluation for CO2 recovery in industrial applications. This global approach suggests a strategy for the evaluation of metal–organic frameworks for gas‐based applications. 相似文献
314.
Christelle TD Hussainb H Dongo E Julius OE Hussain J 《Natural product communications》2011,6(8):1135-1136
Cordia platythyrsa Baker is known for its medicinal value. This paper deals with a phytochemical investigation of this species, from which cordioxime (1), a new dioxime y-lactam has been isolated. Its structure was determined by comprehensive analyses of its 1H and 13C NMR, COSY, HMQC, and HMBC spectroscopic, and HREIMS data. The remaining two known compounds were identified as beta-sitosterol, and beta-sitosterol glucopyranoside. 相似文献
315.
Blanchard PY Alévêque O Boisard S Gautier C El-Ghayoury A Le Derf F Breton T Levillain E 《Physical chemistry chemical physics : PCCP》2011,13(6):2118-2120
The elaboration of mixed self-assembled monolayers (SAMs) of tetrathiafulvalene derivatives allows the modulation of intermolecular interactions and provides evidence of segregated distribution of redox centers. 相似文献
316.
Agnès Le Roux Odile Bellenguez-Morineau Christelle Guéret Damien Prot 《The Journal of the Operational Research Society》2015,66(10):1730-1741
This article deals with a new scheduling problem that arises in the organization of one-to-one meetings in parallel. We first introduce applications of one-to-one meeting scheduling problems. Then, we give an overview of the relevant complexity results. We then prove several complexity results for different versions of the problem. 相似文献
317.
Bog U Smith CL Lee MW Tomljenovic-Hanic S Grillet C Monat C O'Faolain L Karnutsch C Krauss TF McPhedran RC Eggleton BJ 《Optics letters》2008,33(19):2206-2208
We demonstrate postprocessed microfluidic double-heterostructure cavities in silicon-based photonic crystal slab waveguides. The cavity structure is realized by selective fluid infiltration of air holes using a glass microtip, resulting in a local change of the average refractive index of the photonic crystal. The microcavities are probed by evanescent coupling from a silica nanowire. An intrinsic quality factor of 57,000 has been derived from our measurements, representing what we believe to be the largest value observed in microfluidic photonic crystal cavities to date. 相似文献
318.
Haitao Cao Nahed Moutalbi Christelle Harnois Rui Hu Jinshan Li Lian Zhou Jacques G. Noudem 《Physica C: Superconductivity and its Applications》2010,470(1):68-74
Mono-domain YBa2Cu3O7?x (Y123) bulk superconductors have been processed using seeded infiltration growth technique (SIG). The combination of melt infiltrated liquid source (Ba3Cu5O8) into the Y2BaCuO5 (Y211) pre-form and the nucleation of Y123 domain from SmBa2Cu3O7 crystal seed has been investigated. The different configurations of SIG process were compared in this study. In addition, the effect of the starting Y211 particles size has been studied. The results reveal that, the Y211 particle size and different configurations strongly influence the properties of the final bulk superconductor sample. 相似文献
319.
Christelle N’Ta Ambeu Rémy Le Guével Anne Corlu Janat Akhanovna Mamyrbekova Jean-Pierre Bazureau 《Molecular diversity》2018,22(3):685-708
A series of 16 new ethyl \(\upbeta \)-amino benzimidazole acrylate derivatives 12(a–p) with a (2E)-s-cis/trans conformation and bearing two points of diversity was designed and synthesized by using a multi-step strategy (reductive amination, deprotection in acidic media and transamination) in moderate to good yields from ethyl 3-dimethylamino-2-(1H-benzimidazol-2-yl)acrylate (5) and monosubstituted N-Boc diamines (7a,7b) as starting building blocks. Products 12 were evaluated for their in vitro cytotoxic potential against six selected human cell lines (Huh7-D12, Caco2, MDA-MB231, HCT116, PC3 and NCI-H727). Compounds 12a, 12e and 12l exhibited selective and micromolar antitumor activities against Huh7-D12 and Caco2 cell lines. 相似文献
320.
Christelle Miola‐Delaite Erwan Colomb Eric Pollet Thierry Hamaide 《Macromolecular Symposia》2000,153(1):275-286