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51.
Prof. Dr. Axel Reich 《Monatshefte für Mathematik》1982,93(1):33-37
A characterisation of all real Δ≠0 is given, such that $$\overline {f(\sigma + i\Delta \mathbb{N})} = \overline {f(\sigma + i\mathbb{R})} $$ holds for all Dirichlet seriesf(s)=Σa n n ?s and all σ greater than the abscissa of absolute convergence off. For only countably many Δ relation (*) is not valid. By using transcendental results it is shown, that (*) holds in the special case, Δ=1. 相似文献
52.
The thiotungstate [Et4N]2[OW(WS4)2], [Et4N]2.1, containing the linear [[S2W(VI)(mu-S)2]2W(IV)=O] core, was prepared from [Et4N]2[WS4] in the presence of the sulfide scavenger Cd2+. Addition of 1,2-bis(o-diphenylphosphinophenyl)ethane (diphosphine) and Cu+ or Ag+ to solutions of 1 in MeCN/DMF led to coordination of the (diphosphine)Cu/Ag fragments to the terminal sulfido ligands of 1, yielding novel linear pentanuclear, heterometallic clusters [mu-[OW(IV)(DMF)(W(VI)S4)2][M(diphosphine)]2], 2 (M = Cu) and 3 (M = Ag). Along with 2, the trinuclear cluster [[mu-(W(VI)S4)[Cu(diphosphine)(2)]], 4, was also obtained. The molecular and crystal structures of [Et4N]2.1, 2.MeCN, 3.MeCN, and 4.2MeCN.CH2Cl2 have been determined. 相似文献
53.
Axel Schulz Thomas M. Klap tke
T. Stanley Cameron
P. K. Bakshi 《Journal of organometallic chemistry》1994,480(1-2):191-194The oxidation of Cp2NbCl2 with pure WF6 in SO2 solution yielded the cationic metallocene species [Cp2NbCl2]+[WF6]− essentially in quantitative yield. The same reaction carried out in the presence of either equimolar amounts or a two-fold excess of HCN led to the preparation of the new niobocenium salt [Cp2NbCl2]4+[WF6]2− which was studied by single crystal X-ray diffraction. This compound represents the first example of a structurally characterized metallocene-WF6− complex, and crystallizes in the tetragonal system: space group, P41212(No. 92), a = 11.083(8) Å, c = 48.285 (9) Å; Z = 8; R = 0.0759, RW = 0.0841. ab]Die Oxidation von Cp2NbCl2 mit reinem WF6 führt in SO2-Lösung zur Synthese von [Cp2NbCl2 ]+[WF6]− in nahezu quantitativer Ausbeute. Die analoge Reaktion führt unter Anwesenheit der äquimolaren Menge oder eines zweifachen Überschusses an HCN zur Ausbildung des Niobocenium-Komplexsalzes [Cp2NbCl2]4+ [WF6]2−[WCl6]2−, von dem eine Röntgenstrukturanalyse angefertigt wurde. Diese Verbindung repräsentiert den ersten structurell charakterisierten Vertreter eines Metallocen-WF6−-Komplexes und kristallisiert im tetragonalen System: Raumgruppe P41212 (Nr. 92), a = 11.083(8) Å, c = 48.285(9) Å; Z = 8; R = 0.0759, RW = 0.0841. kw]Niobium; X-ray diffraction; Oxidation; Metallocenes 相似文献
54.
Fabian Gerson Axel Lamprecht Markus Scholz Heinz Troxler Dieter Lenoir 《Helvetica chimica acta》1996,79(1):307-318
The radical anions of 5H-dibenzo[a,d]cycloheptene ( 9 ), 5 H-dibenzo[c,f][1,2]diazepine ( 10 ), 5,6-dihydrodibenzo[a,e]cyclooctene ( 11 ), 5,6-dihydrodibenzo[c,g][1,2]diazocine ( 12 ), and (E)-2,2,5,5-tetramethyl-3,4-diphenylhex-3-ene ( 13 ) were characterized by ESR and ENDOR spectroscopy. Their hyperfine data were compared with those previously reported for radical anions also containing the stilbene or the azobenzene π-system. Whereas the π-spin distribution in the radical anions of the stilbene series is only moderately sensitive to deviations of the π-system from planarity, the radical anions of the azobenzene series respond to steric strain by shifting the π-spin population from the benzene rings to the azo group. This finding is impressively demonstrated by the similar hyperfine data for 9 · ? and 11 · ? which contrast with the strongly highly hindered 13 · ?. A. plausible interpretation is readily provided by the electron affinities of the constituent π-moieties in stilbene and azobenzene. While those of benzene and ethene are both comparatively low, the azo group has a considerably higher electron affinity. 相似文献
55.
Marcia Araque-Marin Fabio Bellot Noronha Mickel Capron Franck Dumeignil Michle Friend Egon Heuson Ivaldo Itabaiana Jr. Louise Jalowiecki-Duhamel Benjamin Katryniok Axel Lfberg Sbastien Paul Robert Wojcieszak 《Molecules (Basel, Switzerland)》2022,27(12)
The development of the future French and European bioeconomies will involve developing new green chemical processes in which catalytic transformations are key. The VAALBIO team (valorization of alkanes and biomass) of the UCCS laboratory (Unité de Catalyse et Chimie du Solide) are working on various catalytic processes, either developing new catalysts and/or designing the whole catalytic processes. Our research is focused on both the fundamental and applied aspects of the processes. Through this review paper, we demonstrate the main topics developed by our team focusing mostly on oxygen- and hydrogen-related processes as well as on green hydrogen production and hybrid catalysis. The social impacts of the bioeconomy are also discussed applying the concept of the institutional compass. 相似文献
56.
57.
Prof. Dr. Axel G. Griesbeck Dr. Johannes Uhlig Dr. Thomas Sottmann Dr. Lhoussaine Belkoura Prof. Dr. Reinhard Strey 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(50):16161-16165
Pluronic F‐127 hydrogels are highly efficient microenvironments for photochemical reactions, as demonstrated for singlet oxygen reactions of monoalkenes. Nonpolar substrates are localized in the nanosized polymer compartment, which can be visualized by neutron scattering. The efficiency of 1O2 reactions is strongly increased for tiglate derivatives and the regioselectivity of the ene reaction of trisubstituted alkenes is completely switched in comparison with solution phase and inverted in comparison with intrazeolite photo‐oxygenations. 相似文献
58.
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60.
Prof. Dr. Axel Schulz Dr. Alexander Villinger 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(6):2032-2038
Pure, solvent‐free Zn(N3)2 was prepared by reaction of diethyl zinc and hydrazoic acid in aprotic solvents. The single‐crystal structure determination, along with the comprehensive characterization of α‐Zn(N3)2 and two metastable polymorphs, could be achieved for the first time. Since these data disagree in large parts with the known, previously reported values, all previous syntheses of Zn(N3)2, and for comparison Zn(N3)2?2.5 H2O and Zn(OH)N3 were reinvestigated, indicating that some of the earlier work has to be revised. 相似文献