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991.
Luc Lambs Frédéric Brunet Jean‐Luc Probst 《Rapid communications in mass spectrometry : RCM》2009,23(16):2543-2550
The Garonne is the largest river in the south‐west of France, and its drainage basin stretches between the Pyrénées and the Massif Central mountains. Until now, no water stable isotope study has been performed on the whole Garonne river basin which is composed of different geological substrata, and where the water resources are limited during the dry summer period. This study focuses on the Garonne river and its tributaries from the Pyrénées foothill upstream to its confluence with the Lot River downstream. The aim of the study is to determine the origins of the surface waters using their chemical and stable isotopic compositions (18O, D and 13C), to better understand their circulation within the drainage basin and to assess the anthropogenic influences. The Garonne displays a specific 18O seasonal effect, and keeps its Pyrénean characteristics until its confluence with the Tarn River. The difference in the dissolved inorganic carbon (DIC) comes mainly from the change in lithology between the Pyrénées and the Massif Central mountains. Agriculture activity is only detected in the small tributaries. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
992.
Jean D'Almeida 《Archiv der Mathematik》1987,48(6):543-547
Sans résumé 相似文献
993.
Analytical and Bioanalytical Chemistry - 相似文献
994.
995.
Cristian Peptu Valeria Harabagiu Bogdan C. Simionescu Grazyna Adamus Marek Kowalczuk Jean‐Michel Nunzi 《Journal of polymer science. Part A, Polymer chemistry》2009,47(2):534-547
The synthesis of novel azofunctional oligoesters through bulk ring opening of ε‐caprolactone and D ,L ‐lactide (LA) at 100 and 130 °C, respectively, mediated by N‐ethyl‐N‐(2‐hydroxyethyl)‐4‐(4‐nitrophenylazo)aniline (Disperse Red 1) (DR1) is described. The synthetic procedure allows “clean” products because no catalysts were used in the reaction. Moreover, DR1 moiety is showed for the first time to promote the ring opening of cyclic esters. The molecular structure of the obtained oligoesters was established by NMR spectroscopy, MALDI ToF MS and electrospray ionization mass spectrometry (ESI MS). ESI‐MS/MS fragmentation experiments were used to demonstrate the nature of the chain end groups (hydroxyl and DR1). Intermolecular transesterification reactions were proved by mass spectrometry studies at least in the case of LA oligomerization. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 534–547, 2009 相似文献
996.
997.
A. Ragosine Chercheffsky F. Jean und L. Singer 《Fresenius' Journal of Analytical Chemistry》1902,41(1):45-47
Ohne Zusammenfassung 相似文献
998.
M. Pfrenger Mansfeld Fr. Franz Ludwig Adler D. J. de Jong Hean R. Biazzo Sc. Vigdorchik H. Kerr B. Margosches Jean R. Biazzo und Se. Vigdorcik 《Fresenius' Journal of Analytical Chemistry》1920,59(1):27-30
Ohne Zusammenfassung 相似文献
999.
1000.
Jean Thomas Issenhuth Samuel Dagorne Stphane Bellemin-Laponnaz 《Journal of molecular catalysis. A, Chemical》2008,286(1-2):6-10
The paper describes our preliminary studies on the use of PMHS as a functionalizable polymer and hydride source for the kinetic resolution of secondary alcohols via chiral Cu(I)-catalyzed dehydrogenative silylating process. The chiral phosphine that chelates the Cu metal center has little influence on the selectivity factor of the kinetic resolution. The use of a stereogenic silane appears to be a key requirement to reach enantiodifferentiation in such a process. 相似文献