2 results
Search Results
Now showing 1 - 2 of 2
- ItemEnantiomer-selective magnetization of conglomerates for quantitative chiral separation(Berlin : Springer Nature, 2019) Ye, X.; Cui, J.; Li, B.; Li, N.; Wang, R.; Yan, Z.; Tan, J.; Zhang, J.; Wan, X.Selective crystallization represents one of the most economical and convenient methods to provide large-scale optically pure chiral compounds. Although significant development has been achieved since Pasteur’s separation of sodium ammonium tartrate in 1848, this method is still fundamentally low efficient (low transformation ratio or high labor). Herein, we describe an enantiomer-selective-magnetization strategy for quantitatively separating the crystals of conglomerates by using a kind of magnetic nano-splitters. These nano-splitters would be selectively wrapped into the S-crystals, leading to the formation of the crystals with different physical properties from that of R-crystals. As a result of efficient separation under magnetic field, high purity chiral compounds (99.2 ee% for R-crystals, 95.0 ee% for S-crystals) can be obtained in a simple one-step crystallization process with a high separation yield (95.1%). Moreover, the nano-splitters show expandability and excellent recyclability. We foresee their great potential in developing chiral separation methods used on different scales. © 2019, The Author(s).
- ItemX-ray nanodiffraction on a single SiGe quantum dot inside a functioning field-effect transistor(Washington, DC : American Chemical Society, 2011) Hrauda, N.; Zhang, J.; Wintersberger, E.; Etzelstorfer, T.; Mandl, B.; Stangl, J.; Carbone, D.; Holý, V.; Jovanović, V.; Biasotto, C.; Nanver, L.K.; Moers, J.; Grützmacher, D.; Bauer, G.For advanced electronic, optoelectronic, or mechanical nanoscale devices a detailed understanding of their structural properties and in particular the strain state within their active region is of utmost importance. We demonstrate that X-ray nanodiffraction represents an excellent tool to investigate the internal structure of such devices in a nondestructive way by using a focused synchotron X-ray beam with a diameter of 400 nm. We show results on the strain fields in and around a single SiGe island, which serves as stressor for the Si-channel in a fully functioning Si-metal-oxide semiconductor field-effect transistor.