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1.
Improvement of matrix effects correction in X-ray fluorescence analysis through the optimum relation
A computer program for the optimization of relation for correction of matrix effects in Energy Dispersive X-Ray Fluorescence (EDXRF) analysis is described Program functioning and correction efficiency is studied experimentally in the case of silicate geological samples. 相似文献
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Sylviane Sabo Bruno Chaudret Danièle Gervais 《Journal of organometallic chemistry》1985,292(3):411-418
The possibility of making metal—metal bonded heterobimetallic species by metathesis of ruthenium dichlorides with anionic carbonylates is demonstrated by the isolation of MoRu(μ-Cl)(μ-CO)(CO)2(PPh3)2(η-C5H5) (1) and MnRuCl(μ-CO)2(CO)3(μ-dppm)2 (2), obtained by action of [Mo(CO)3(η-C5H5]? on RuCl2(PPh3)3 and of Mn(CO)5? on RuCl2(dppm)2, respectively. In contrast, reaction of Mn(CO)5? with RuCl2(PMe3)4 yielded an ionic species 3 containing the diruthenium cation Ru2Cl3(PMe3)6+. More interestingly, the action of Mn(CO)5? on RuCl2(PPh3)3 resulted in the formation of the unexpected complex MnRu(μ-PPh2)(CO)6(PPh3)2 (4) in which the phosphido group PPh2 bridges the two metals; this process is shown to involve a hydride intermediate, and elimination of a molecule of benzene, both identified in the reaction mixture. 相似文献
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Redox‐Active‐Ligand‐Mediated Formation of an Acyclic Trinuclear Ruthenium Complex with Bridging Nitrido Ligands 下载免费PDF全文
Dr. Bidraha Bagh Daniël L. J. Broere Dr. Maxime A. Siegler Dr. Ir. Jarl Ivar van der Vlugt 《Angewandte Chemie (International ed. in English)》2016,55(29):8381-8385
Coordination of a redox‐active pyridine aminophenol ligand to RuII followed by aerobic oxidation generates two diamagnetic RuIII species [ 1 a (cis) and 1 b (trans)] with ligand‐centered radicals. The reaction of 1 a / 1 b with excess NaN3 under inert atmosphere resulted in the formation of a rare bis(nitrido)‐bridged trinuclear ruthenium complex with two nonlinear asymmetrical Ru‐N‐Ru fragments. The spontaneous reduction of the ligand centered radical in the parent 1 a / 1 b supports the oxidation of a nitride (N3?) to half an equivalent of N2. The trinuclear omplex is reactive toward TEMPO‐H, tin hydrides, thiols, and dihydrogen. 相似文献
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The synthesis and spectroscopic studies of a convex bis-porphyrin based molecular tweezer are reported. The complexation of small bidentate ligands by metallated derivatives of the bis-porphyrin host were monitored through UV–visible and 1H NMR spectroscopy and yielded large association constants. 相似文献
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S. G. Dani 《印度理论与应用数学杂志》2010,41(1):241-250
We discuss some properties of nilpotent Lie groups and their application in proving the embedding theorem for infinitely divisible
probability measures on locally compact groups. 相似文献
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Eva C. Sonnenschein Marc Stierhof Stephan Goralczyk Floriane M. Vabre Leonie Pellissier Kine Østnes Hanssen Mercedes de la Cruz Caridad Díaz Peter de Witte Daniëlle Copmans Jeanette Hammer Andersen Espen Hansen Venke Kristoffersen José R. Tormo Rainer Ebel Bruce F. Milne Hai Deng Lone Gram Jioji N. Tabudravu 《Tetrahedron》2017,73(18):2633-2637
A new siderophore containing a 4,5-dihydroimidazole moiety was isolated from Pseudoalteromonas piscicida S2040 together with myxochelins A and B, alteramide A and its cycloaddition product, and bromo- and dibromoalterochromides. The structure of pseudochelin A was established by spectroscopic techniques including 2D NMR and MS/MS fragmentation data. In bioassays selected fractions of the crude extract of S2040 inhibited the opportunistic pathogen Pseudomonas aeruginosa. Pseudochelin A displayed siderophore activity in the chrome azurol S assay at concentrations higher than 50 μM, and showed weak activity against the fungus Aspergillus fumigatus, but did not display antibacterial, anti-inflammatory or anticonvulsant activity. 相似文献