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21.
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Doezé RH Maltman BA Egan CL Ulijn RV Flitsch SL 《Angewandte Chemie (International ed. in English)》2004,43(24):3138-3141
23.
Beatrice Severino 《Tetrahedron》2009,65(1):206-1637
In this paper, we describe the synthesis of conformationally constrained dipeptide mimetic derivatives. Microwave flash heating was used in several synthetic steps providing the opportunity to perform the reactions in dramatically shortened time as well as to increase the obtained yields. The efficiency of the methodology makes it useful in order to prepare other dipeptides containing the 4-amino-tetrahydro-2-benzazepin-3-one motif. 相似文献
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Aneta Slodczyk Philippe Colomban Daniel Lamago Marie-Helene Limage François Romain Stephanie Willemin Beatrice Sala 《Ionics》2008,14(3):215-222
H+-containing lanthanide-doped perovskites A(Ba, Sr etc.)B(Zr, Ce, Ti etc.)O3 are potential ceramic membranes for fuel cell and medium temperature water electrolysis (300–800 °C). The comparison studies
of the hydrated and non-hydrated Yb-doped BaZrO3 and SrZrO3 were performed by thermal expansion, medium–high temperature neutron and room-temperature high-pressure Raman scattering.
Neutron diffraction and elastic/quasi-elastic studies carried out for BaZrO3 ceramic show the presence of the protons, their successive diffusion above ∼600 °C, and then their departure above 750 °C
(under vacuum). Phase transitions and their modification by proton insertion are discussed. A high-pressure Raman study of
SrZrO3 performed at room temperature in the diamond anvil cell reveals the presence of two pressure-induced phase transitions at
about 5 and 22 GPa and confirms that proton insertion modifies the phase transition sequences.
Paper presented at the 11th EuroConference on the Science and Technology of Ionics, Batz-sur-Mer, Sept. 9–15, 2007. 相似文献
26.
Olga Bortolini Beatrice Russo Giovanni Sindona Amedeo Tocci 《Tetrahedron letters》2007,48(40):7125-7128
1,3-Dipolar cycloadditions of nitrones with alkenes afforded the corresponding isoxazolidines in ionic liquids in the presence of Er(OTf)3. The ionic liquid and the catalyst are recycled up to five times without any specific treatment or loss of activity. Extension of the procedure to the synthesis of isoxazolidinyl nucleosides has been investigated. 相似文献
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The presumably "small molecule structure" of the organopalladium complex rac-PdCl(C(6)H(3)-4-OMe-CHMeNH(2))(py) crystallizes with 16 molecules in the asymmetric unit, a highly unusual situation according to the CSD database. The symmetrically independent residues differ with respect to soft conformational degrees of freedom. Packing in the acetonitrile solvate of the same compound is unexceptional. 相似文献
29.
Liliana Mititelu-Tartau Maria Bogdan Daniela Angelica Pricop Beatrice Rozalina Buca Ana-Maria Pauna Lorena Anda Dijmarescu Ana-Maria Pelin Liliana Lacramioara Pavel Gratiela Eliza Popa 《Molecules (Basel, Switzerland)》2021,26(13)
This paper is focused on the in vivo release and biocompatibility evaluation in rats of some novel systems entrapping zinc chloride in lipid vesicles. The particles were prepared by zinc chloride immobilization inside lipid vesicles made using phosphatidylcholine, stabilized with 0.5% chitosan solution, and dialyzed for 10 h to achieve a neutral pH. The submicrometric systems were physico-chemically characterized. White Wistar rats, assigned into four groups of six animals each, were treated orally with a single dose, as follows: Group I (control): deionized water 0.3 mL/100 g body weight; Group II (Zn): 2 mg/kg body weight (kbw) zinc chloride; Group III (LV-Zn): 2 mg/kbw zinc chloride in vesicles; Group IV (LVC-Zn): 2 mg/kbw zinc chloride in vesicles stabilized with chitosan. Haematological, biochemical, and immune parameters were assessed after 24 h and 7 days, and then liver fragments were collected for histopathological examination. The use of zinc submicrometric particles—especially those stabilized with chitosan—showed a delayed zinc release in rats. No substantial changes to blood parameters, plasma biochemical tests, serum complement activity, or peripheral neutrophils phagocytic capacity were noted; moreover, the tested substances did not induce liver architectural disturbances. The obtained systems provided a delayed release of zinc, and showed good biocompatibility in rats. 相似文献
30.
The idea that the pomeron has partonic structure similar to any other hadron has been given strong support by recent measurements of the diffractive structure function at HERA. We present a detailed theoretical analysis of the diffractive structure function under the assumption that the diffractive cross section can be factorized into a pomeron emission factor and the deep inelastic scattering cross section of the pomeron. We pay particular attention to the kinematic correlations implied by this picture, and suggest the measurement of an angular correlation which should provide a first test of the whole picture. We also present two simple phenomenological models for the quark and gluon structure of the pomeron, which are consistent with various theoretical ideas and which give equally good fits to recent measurements by the H1 collaboration, when combined with the pomeron emission factor of Donnachie and Landshoff. We predict that a large fraction of diffractive deep inelastic events will contain charm, and discuss how improved data will be able to distinguish the models. 相似文献