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Aarnts MP Wilms MP Peelen K Fraanje J Goubitz K Hartl F Stufkens DJ Baerends EJ Vlcek A 《Inorganic chemistry》1996,35(19):5468-5477
Ru(SnPh(3))(2)(CO)(2)(iPr-DAB) was synthesized and characterized by UV-vis, IR, (1)H NMR, (13)C NMR, (119)Sn NMR, and mass (FAB(+)) spectroscopies and by single-crystal X-ray diffraction, which proved the presence of a nearly linear Sn-Ru-Sn unit. Crystals of Ru(SnPh(3))(2)(CO)(2)(iPr-DAB).3.5C(6)H(6) form in the triclinic space group P&onemacr; in a unit cell of dimensions a = 11.662(6) ?, b = 13.902(3) ?, c = 19.643(2) ?, alpha = 71.24(2) degrees, beta = 86.91(4) degrees, gamma = 77.89(3) degrees, and V = 2946(3) ?(3). One-electron reduction of Ru(SnPh(3))(2)(CO)(2)(iPr-DAB) produces the stable radical-anion [Ru(SnPh(3))(2)(CO)(2)(iPr-DAB)](*-) that was characterized by IR, and UV-vis spectroelectrochemistry. Its EPR spectrum shows a signal at g = 1.9960 with well resolved Sn, Ru, and iPr-DAB (H, N) hyperfine couplings. DFT-MO calculations on the model compound Ru(SnH(3))(2)(CO)(2)(H-DAB) reveal that the HOMO is mainly of sigma(Sn-Ru-Sn) character mixed strongly with the lowest pi orbital of the H-DAB ligand. The LUMO (SOMO in the reduced complex) should be viewed as predominantly pi(H-DAB) with an admixture of the sigma(Sn-Ru-Sn) orbital. Accordingly, the lowest-energy absorption band of the neutral species will mainly belong to the sigma(Sn-Ru-Sn)-->pi(iPr-DAB) charge transfer transition. The intrinsic strength of the Ru-Sn bond and the delocalized character of the three-center four-electron Sn-Ru-Sn sigma-bond account for the inherent stability of the radical anion. 相似文献
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F. Asinger H. Offermanns A. Saus C. Dudeck D. Neuray E. Wilms 《Monatshefte für Chemie / Chemical Monthly》1973,104(1):118-136
Zusammenfassung Die Darstellung einigerMannichbasen (3 a-f) bzw.Mannich-basen-hydrochloride (2 a-f) und zahlreicher s-Triazin-Derivate (4 a-d, 5 a–m, 6 a–w, 7 a–e, 8 a–d, und9 a–l) auf Basis des unsubstituierten Thiomorpholins (1 a) sowie C-mono-[2-Methylthiomorpholin (1 b) und 2-Äthylthiomorpholin (1 c)] und C-dialkylierter Thiomorpholine [2-Methyl-3-äthylthiomorpholin (1 d)] wird beschrieben.
HerrE. Wilms dankt der Deutschen Texaco AG. für die Gewährung eines Stipendiums herzlichst. 相似文献
Concomitant action of elementary sulfur and gaseous ammonia upon ketones, LXXIX: On the reactivity of alkyl substituted thiomorpholines, I
The preparation of someMannichbases (3 a-f) andMannich base hydrochlorides (2 a-f), resp., and numerous s-triazine derivatives (4 a-d, 5 a–m, 6 a–w, 7 a–e, 8 a–d, and9 a–l) based upon unsubstituted thiomorpholine (1 a) as well as C-mono-[2-methylthiomorpholine (1 b) and 2-ethylthio-morpholine (1 c)] and C-dialkylated thiomorpholines [2-methyl-3-ethylthiomorpholine (1 d)] is described.
HerrE. Wilms dankt der Deutschen Texaco AG. für die Gewährung eines Stipendiums herzlichst. 相似文献
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Knowledge of residence time is a critical aspect in developing control and material diversion strategies for continuous manufacturing processes in pharmaceutica... 相似文献
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Natalie Hell Peter Beiersdorfer Gregory V. Brown Megan E. Eckart Richard L. Kelley Caroline A. Kilbourne Maurice A. Leutenegger Thomas E. Lockard F. Scott Porter Jörn Wilms 《X射线光谱测定》2020,49(1):218-233
X-ray astronomy and ground-based atomic physics have a long history of fruitful collaboration: Sound understanding of the underlying atomic physics is the key to reliable interpretation of the spectra from celestial sources; conversely, astronomical spectra have been used to benchmark and advance atomic physics. This interplay is about to become even more important as we enter a new era of high-resolution X-ray astrophysics with large effective collection area. Although high-resolution observations with the gratings on the Chandra and XMM-Newton observatories continue to drive new science, upcoming planned and proposed missions will open up new discovery space in the near future that is currently challenging to access: high-resolution spectroscopy on extended sources, in the Fe K band, and on short time scales. This review summarizes open questions in these areas and the design parameters for the Hitomi, XRISM, Athena, and Arcus observatories. The expected high quality of spectra taken with these observatories puts new constraints on the accuracy of atomic reference data required to take full advantage of the diagnostic potential of these spectra. 相似文献
6.
Exact numerical calculations have been performed on a system of N piezoelectric particles with a random distribution of particle size. The calculations are based on an orientational method as given by Melcher abd Shiren.6 The model explains all essential properties observed for such a system. 相似文献
7.
We consider one-dimensional wave propagation in a thermoelastically coupled half space. The boundary conditions involve an application of a non-zero temperature or temperature gradient. The strain, temperature, stress and particle velocity are obtained and compared when both time and distance are large. The ratios of the temperature to the strain, the stress to the strain, and the particle velocity to the strain are found to be the same for all the six cases considered. 相似文献
8.
Summary An HPLC-method for the measurement of blood Cyclosporin A levels (CyA) of renal allograft transplanted patients within 9min
is described. After a simple protein precipitation of the blood the supernatant is transferred to an HPLC-system. The short
time of analysis is obtained by a step gradient elution technique and a precolumn separation of the fractions of interest
followed by a backflush regeneration step of the precolumn. The analysis of the fraction of interest takes place on a column
with high resolution power as long as the precolumn is regenerated. CyA is monitored by UV-absorption at 206nm. Detection
of 20 to 2000ng/ml CyA allows the use of the method for patient monitoring and for research purposes.
Presented at the 15th International Symposium on Chromatography, Nürnberg, October 1984 相似文献
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