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1.
C. Mahr 《Fresenius' Journal of Analytical Chemistry》1940,120(1-2):6-9
Ohne Zusammenfassung 相似文献
2.
C. Mahr H. Bergmann P. Zuman J. Sunkel K. -J. Range K. -H. König W. Schermann G. Manecke A. Sippel E. Best K. Hartl J. Volke H. Kübler P. Moritz H. H. Pfeiffer E. Knickmann H. Lüken 《Colloid and polymer science》1967,218(2):158-171
Ohne Zusammenfassung 相似文献
3.
Basic Metals. LXIV. Lewis-basic Bis(trimethylphosphine)cobalt Complexes with Indenyl and Trifluormethylcyclopentadienyl as Ligands The half-sandwich type compounds C9H7Co(PMe3)2 ( 1 ) and (C5H4CF3)Co(PMe3)2 ( 6 ) are prepared from CoCl(PMe3)3 and C9H7Li or TlC5H4CF3, respectively. They behave like metal bases and react with HBF4, CH3I (or CF3SO3CH3), I2, and CH3COCl by oxidative addition to give the cationic complexes [C9H7CoX(PMe3)2]+ and [(C5H4CF3)CoX(PMe3)2]+ (X ? H, CH3, I, COCH3) which are isolated as the PF6 salts ( 2–5 and 7–10 ). The 1HNMR and the IR spectra of the compounds 1–10 are discussed, also in comparison to those of the corresponding cyclopentadienylcobalt complexes. 相似文献
4.
5.
Werner H Schwab P Bleuel E Mahr N Windmüller B Wolf J 《Chemistry (Weinheim an der Bergstrasse, Germany)》2000,6(24):4461-4470
A series of carbenerhodium(I) complexes of the general composition [(eta5-C5H5)Rh(=CRR')(L)] (2a-2i) with R = R'= aryl and L = SbiPr3 or PR3 has been prepared from the square-planar precursors trans-[RhCl(=CRR')(L)2] and NaC5H5 in excellent yields. Reaction of the triisopropylsibane derivative 2a. which contains a rather labile Rh-Sb bond, with CO, PMe3, and CNR (R = Me, CH2Ph, tBu) leads to the displacement of the SbiPr3 ligand and affords the substitution products [(eta5-C5H5)Rh(=CPh2)(L)] (3-7). In contrast, treatment of the triisopropylphosphane compound 2c with CO and CNtBu leads to the cleavage of the Rh=CPh2 bond and gives besides [(eta5-C5H5)Rh(PiPr3)(L)] (10, 12) by metal-assisted C-C coupling diphenylketene Ph2C=C=O (11) or the corresponding imine Ph2C=C=NtBu (13). While the reaction of 2a, c with C2H4 yields [(eta5-C5H5)Rh(C2H4)(L)] (14, 15) and the trisubstituted olefin Ph2C=CHCH3 (16), treatment of 2a, c with RN3 leads to the cleavage of both the Rh-EiPr3 and Rh=CPh2 bonds and gives the chelate complexes [(eta5-C5H5)Rh(kappa2-RNNNNR)] (19, 20). The substitution products 3 (L=CO) and 4 (L= PMe3) react with an equimolar amount of sulfur or selenium by addition of the chalcogen to the Rh=CPh2 bond to generate the complexes [(eta5-C5H5)Rh(kappa2-ECPh2)(L)] (21-24) with thio- or selenobenzophenone as ligand. Similarly, treatment of 3 with CuCl affords the unusual 1:2 adduct [(eta5-C5H5)(CO)Rh(mu-CPh2)(CuCl)2] (25), which reacts with NaC5H5 to form [(eta5-C5H5)(CO)Rh(muCPh2)Cu(eta5-C5H5)] (26). The molecular structures of 3 and 22 have been determined by X-ray crystallography. 相似文献
6.
C. Pertusi R. E. Essery P. Mougnaud F. H. Zschacke G. Batchelder V. W. Meloche R. H. Carter und C. Mahr 《Fresenius' Journal of Analytical Chemistry》1932,88(1-2):55-58
Ohne Zusammenfassung 相似文献
7.
C. Mahr und Hertha Ohle 《Fresenius' Journal of Analytical Chemistry》1938,115(7-8):254-257
Ohne Zusammenfassung 相似文献
8.
Beeke Gerken Christoph Mahr Jakob Stahl Tim Grieb Marco Schowalter Florian F. Krause Thorsten Mehrtens Lutz Mädler Andreas Rosenauer 《Particle & Particle Systems Characterization》2023,40(9):2300048
Hetero-contacts are interfaces between different materials at the nanoscale leading to novel functional properties. In hetero-aggregates, primary particles of at least two different materials are mixed at primary particle or cluster level. Double flame spray pyrolysis (DFSP) is a versatile technique for the controlled synthesis of such materials. Characterization of hetero-aggregates by scanning transmission electron microscopy (STEM) requires acquisition and evaluation of many aggregate images in order to derive statistically significant results. Usually, STEM energy dispersive X-ray spectroscopy (EDXS) is used to acquire elemental maps providing the material distribution of the primary particles within hetero-aggregates. However, the acquisition of a single EDXS map takes up to several minutes. For this reason, determination of material types of primary particles from the intensity in high-angle annular dark field STEM images alone is desirable. These images can be acquired within a couple of seconds. In the present work, a method is suggested which allows for achieving this objective. It can be applied to distinguish materials with a significant difference in their atomic number and hence sufficient material contrast in the STEM images. 相似文献
9.
G. Stork und C. Mahr 《Fresenius' Journal of Analytical Chemistry》1966,222(4):363-369
Zusammenfassung Zur röntgenfluorescenzanalytischen Bestimmung eines Elementes in beliebigen Materialien kann die Additionsmethode erfolgreich benutzt werden. Sie ist jedoch nicht für eine Gesamtanalyse anwendbar. Für diesen Zweck wurde eine abgeänderte Arbeitsweise entwickelt: zunächst wird das Additionsverfahren durchgeführt; aus dem Ergebnis werden zwei Eichpräparate (Boraxschmelzen) berechnet, die dann mit der Boraxschmelze der Probe verglichen werden, um deren Zusammensetzung zu erhalten.
I. Mitt.: Mahr, C., u. G. Stork [1].
Wir danken der Deutschen Forschungsgemeinschaft für die Unterstützung dieser Arbeiten. 相似文献
Summary In X-ray fluorescence analysis the addition method is a useful procedure for the determination of one component of various substances. It is not applicable to total analysis. Therefore a variant of this procedure is described: first, the addition method is carried out; the result of this procedure is used to calculate two calibration samples (borax melts); the comparison of these two samples with the borax melt of the material to be analysed yields the composition of the substance.
I. Mitt.: Mahr, C., u. G. Stork [1].
Wir danken der Deutschen Forschungsgemeinschaft für die Unterstützung dieser Arbeiten. 相似文献
10.
The current distribution on microstrip stub antennas is calculated with the appropriate Green's functions via an integral equation, which is solved with the moment method. As expansion functions for the current cubic spline functions are used. The calculated data are used for the design of a microstrip array with Chebyshev characteristics. 相似文献