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排序方式: 共有889条查询结果,搜索用时 31 毫秒
861.
R.P. Drake F.W. Doss R.G. McClarren M.L. Adams N. Amato D. Bingham C.C. Chou C. DiStefano K. Fidkowski B. Fryxell T.I. Gombosi M.J. Grosskopf J.P. Holloway B. van der Holst C.M. Huntington S. Karni C.M. Krauland C.C. Kuranz E. Larsen B. van Leer B. Mallick D. Marion W. Martin J.E. Morel E.S. Myra V. Nair K.G. Powell L. Rauchwerger P. Roe E. Rutter I.V. Sokolov Q. Stout B.R. Torralva G. Toth K. Thornton A.J. Visco 《High Energy Density Physics》2011,7(3):130-140
862.
863.
Lara M Dayou F Launay JM Bergeat A Hickson KM Naulin C Costes M 《Physical chemistry chemical physics : PCCP》2011,13(18):8127-8130
The integral cross section of the S((1)D(2)) + H(2)(j = 0) → SH + H reaction has been measured for the first time at collision energies from 0.820 down to 0.078 kJ mol(-1) in a high-resolution crossed beam experiment. The excitation function obtained exhibits a non-monotonic variation with collision energy and compares well with the results of high-level quantum calculations. In particular, the structures observed in the lower energy part, where only a few partial waves contribute, can be described in terms of the sequential opening of individual channels, consistent with the theoretical calculations. 相似文献
864.
Alves G Morel L El-Ghozzi M Avignant D Legeret B Nauton L Cisnetti F Gautier A 《Chemical communications (Cambridge, England)》2011,47(27):7830-7832
A platinum Chugaev complex was synthesised and fully characterized by multinuclear NMR spectroscopy and X-ray crystallography. This cis bis acyclic diamino carbene complex acts as a cytotoxic compound and behaves as a cisplatin equivalent by interacting with supercoiled DNA and thiols. Stability of the ligand is also discussed. 相似文献
865.
In this article, we study three aspects of mean field games (MFG). The first one is the case when the dynamics of each player depend on the strategies of the other players. The second one concerns the modeling of “noise” in discrete space models and the formulation of the Master Equation in this case. Finally, we show how MFG reduce to agent based models when the intertemporal preference rate goes to infinity, i.e. when the anticipation of the players vanishes. 相似文献
866.
S. Sapino M. E. Carlotti R. Cavalli E. Ugazio G. Berlier L. Gastaldi S. Morel 《Journal of inclusion phenomena and macrocyclic chemistry》2013,75(1-2):69-76
Gamma-oryzanol (GO), a mixture of ferulic acid esters, has recently attracted a great interest as natural antioxidant extracted from rice-bran oil, usually employed to stabilize food and pharmaceutical raw materials, moreover as sunscreen in cosmetic formulations. Its usefulness, however, is limited by its fast degradation. A recently proposed approach to increase the stability and effectiveness of antioxidants is based on the inclusion in supramolecular structures (nanoparticles, cyclodextrins, liposomes, etc.). In this work we studied the inclusion of GO in β-cyclodextrin-based nanosponges which in the last few years have been chosen for their ability to encapsulate a great variety of substances to decrease their side-effects and to protect them from degradation. The inclusion complex was prepared in 1:1 w/w ratio and characterized by DSC, XRPD and membrane diffusion runs. The photodegradation of GO upon either UVA or UVB irradiation was found to be slowed down by inclusion in nanosponges. The antioxidant effectiveness of the inclusion complex was also assessed and in vitro experiments on porcine ear skin revealed a certain accumulation of GO also when entrapped in the host structure. 相似文献
867.
Maria Eugenia Carlotti Simona Sapino Elena Ugazio Marina Gallarate Silvia Morel 《Journal of Dispersion Science and Technology》2013,34(4):465-471
This article investigates the possibility of producing solid lipid nanoparticles (SLN) as protective vehicle of resveratrol, an antioxidant characterized by a fast trans-cis isomerization. SLN aqueous dispersions were produced by hot melt homogenization technique and characterized. It was found that the presence of tetradecyl-γ-cyclodextrin in SLN formulation induced an improvement of nanoparticle characteristics. Moreover, a significant reduction in resveratrol photodegradation was noted when the molecule was entrapped in SLN which became more pronounced in the presence of tetradecyl-γ-cyclodextrin. A notable in vitro porcine skin accumulation and an increased antioxidative efficacy were observed by entrapping resveratrol in nanoparticles. 相似文献
868.
The dilution of series of oil-in-water microemulsions, formulated with Aerosol-OT as surfactant, water, isopropyl myristate as oil and varying amounts of butanol as cosurfactant, was studied. An infinite dilution could be obtained only adding water containing surfactant; the minimum amount of Aerosol-OT required was determined. The behaviour of the microemulsions upon dilution was related to the presence of nixed micelles in the aqueous phase. 相似文献
869.
The synthesis of 9-Methoxy-1-methyl-1H,6H-pyrazolo[4,3-c]carbazole is reported in four steps from 6-nitroindazole. Palladium acetate mediated cyclization gave only the “bent” tetracyclic derivative. 相似文献
870.
Jean Guillon Pascal Sonnet Jean-Pierre Malval Stéphane Massip Isabelle Gosse Jean-Michel Léger 《Supramolecular chemistry》2013,25(5):437-451
The preparation of new 25,27-bis(alkyloxy)calix[4]arenes-crown-6 in the cone, partial-cone and 1,3-alternate conformation is reported. We have also investigated the alkylation of the cone monoalkylated calix[4]arene-crown-6 achieved using Cs 2 CO 3 . This reaction afforded a mixture of cone and partial-cone calix[4]arenes-crown-6 having an alkyl chain anti or syn to the polyether ring. Conformations have been probed using 1 H, 13 C, 2D-NMR and NOESY analysis, and using X-ray crystallography. Extraction experiments using a two-phase solvent method involving cesium picrate were performed for these newly synthesized conformers. They reveal and confirm the strong preference for the 1,3-alternate conformers. The affinity of 1,3-alternate calixarenes for Cs + has been assessed by complexation measurements (log g ) using a spectrophotometric technique. No significant Cs + extraction difference was observed in relation to the nature of the alkyl chains on the aromatic rings. 1 H NMR studies of the 1,3-alternate calixarene Cs + complexes confirms the cation's spacial position between the two aromatic rings, due to cation- ~ interactions. 相似文献