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111.
[Ba2(H2O)9][GeSe4] is suitable for the formation of novel M/14/16 anions [Mn6Ge4Se17]6- --discrete or linked in an as yet unprecedented porous network--with antiferromagnetically coupled Mn(II) centers and relatively small electronic excitation energies. 相似文献
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Wienkoop S Larrainzar E Niemann M Gonzalez EM Lehmann U Weckwerth W 《Journal of separation science》2006,29(18):2793-2801
Mass spectrometry (MS) has become a powerful tool for the quantitative analysis of complex protein samples. A high-throughput strategy for the comparative analysis of multiple protein samples with high complexity becomes more and more important. Two strategies, spectral count and peak intensity, for label-free MS analysis of prefractionated complex mixtures have been described recently to be useful for quantitation. Here we compare both strategies for rapid and quantitative 1-D shotgun LC/MS/MS analyses of highly complex protein mixtures using silica-based monolithic columns. First, we validated linearity and sensitivity of these methods by spiking varying amounts of an internal standard protein in a complex plant protein extract. Secondly, quantitative data of proteins of Medicago truncatula nodules were visualized with independent components analysis using data either obtained from spectral count or peak integration performed with commercial software. Spectral count showed apparent advantages over peak integration because several peptides per protein are automatically averaged, the linear dynamic range of quantitation increases in complex matrices and the number of quantified proteins surpasses the number of proteins using peak integration. Thus, for the need of rapid comparative analysis of highly complex protein samples, spectral count enables sample pattern recognition and identification of biomarkers in nongel based proteomic studies. 相似文献
114.
Stefanie Scholtyssek Rameshwar Adhikari Volker Seydewitz Goerg Hannes Michler Eric Baer Anne Hiltner 《Macromolecular Symposia》2010,294(1):33-44
Nanostructured polymers and ultra-thin polymer layers are used more and more in technical applications like nanotechnology and microelectronics. Therefore, it is really important to understand the size-scale dependent properties as bulk polymers become thinner and more two-dimensional. Here the morphology as well as the macroscopic and the microscopic deformation behaviour of multilayered films of polypropylene (PP) and polystyrene (PS) have been investigated. For investigation different microscopic techniques and tensile testing were used. The films were prepared by multilayer coextrusion, whereas the composition of PP and PS and the film thickness – and therefore the thickness of each layer – varied. The thinnest calculated thickness of a single layer was about 5 nm. It is shown that the PP/PS films consist usually of homogeneous layers with only few defects. As the composition of PP/PS deviates strongly from 50/50 or the films get thinner the number of defects increases and the layered system turns to irregular lamellar system. In macroscopic tensile tests the small PS layers affect the elongation at break enormously: Most of the samples are brittle. For the films with a composition of PP/PS 90/10 and the film PP/PS 70/30 with a film thickness of 25 µm an elongation at break of 66% and higher could be reached. Transmission electron microscopy on these samples shows that the layers are characterized by plastic yielding in local deformation zones. 相似文献
115.
In this work, the simulation of earings in cup drawing by means of a recently developed anisotropic combined hardening material model is discussed. The model represents a multiplicative formulation of anisotropic elastoplasticity in the finite strain regime with nonlinear kinematic and isotropic hardening. Plastic anisotropy is described by the use of second-order structure tensors as additional arguments in the representation of the yield function and the plastic flow rule. The evolution equations are integrated by a form of the exponential map that preserves the plastic volume and the symmetry of the internal variables. Finite element simulations of cylindrical cup drawing processes are performed by means of ABAQUS/Standard where the discussed material model has been implemented into a user-defined reduced integration solid-shell element. (© 2010 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
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The extraction of stoichiometric ternary K/Si/P, K/Ge/P, and K/Si/As solid mixtures with en/crypt‐222 afforded compounds with binary anions of the respective groups 14/15 elemental combination. Although the analysis of the products turned out to be extremely difficult owing to their intrinsically poor crystallinity and low solubility, we have evidence that one of them contains (SiP6H2)2– anions. Preliminary data from the two other compounds indicate the existence of the heavier Ge/P and Si/As variants as well. The combination of all analytical results, including X‐ray crystallography, energy‐dispersive X‐ray (EDX) spectroscopy, electrospray ionization mass spectrometry (ESI‐MS), and nuclear magnetic resonance (NMR) spectroscopy, point towards the named composition of the anions and their doubly protonated nature. By this, they represent the first binary Zintl anions of the Si/P and Si/As elemental combination and complement the recent endeavors to synthesize binary Zintl anions of the light(er) p‐block elements. We discuss our attempts to elucidate the clusters' identity and provide our results as the most probable interpretation of the data, additionally corroborated by quantum chemical analyses. 相似文献
118.
Conrad A. P. Goodwin Jing Su Thomas E. Albrecht‐Schmitt Anastasia V. Blake Enrique R. Batista Scott R. Daly Stefanie Dehnen William J. Evans Andrew J. Gaunt Stosh A. Kozimor Niels Lichtenberger Brian L. Scott Ping Yang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(34):12050-12050
119.
Niels Lichtenberger Werner Massa Stefanie Dehnen 《Angewandte Chemie (International ed. in English)》2019,58(10):3222-3226
We present the results from a reactivity study of the binary anion (TlBi3)2? towards Group 12 metal compounds MPh2 (M=Zn, Cd, Hg) to gain access to coordination compounds of polycyclic polypnictide molecules such as Bi73? or Bi113?. The coordination chemistry of these polybismuthide cages has been unprecedented to date, while it has been known for a long time for the lighter Group 15 anions Pn73? (Pn=P, As, Sb). The use of (TlBi3)2?, previously shown to release Tl under certain conditions in situ, resulted in the formation of the first heterometallic polyanion in which a nortricyclane‐type polybismuthide coordinates a transition‐metal atom, [(Bi7)Cd(Bi7)]4?. Reactions with the lighter Group 12 metal precursor yielded the uncommon ternary cluster [(Bi6)Zn3(TlBi5)]4?, most likely representing a reaction intermediate, and at the same time hinting at the formation of the nortricyclane‐shaped cage. Quantum‐chemical studies provide deeper insight into the stability trends of the [(E7)M(E7)]4? anion family and reveal a complex bonding situation in [(Bi6)Zn3(TlBi5)]4?, which features both localized and multi‐center bonding. 相似文献
120.