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101.
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Roberts Austen C. Gaab Walther Dürr Siegert Uehling und Steinbart 《Fresenius' Journal of Analytical Chemistry》1894,33(1):716-717
Ohne Zusammenfassung 相似文献
104.
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106.
Walther Dyck 《Mathematische Annalen》1880,17(4):510-516
Ohne Zusammenfassung 相似文献
107.
Walther Hempel 《Fresenius' Journal of Analytical Chemistry》1881,20(1):499-502
Ohne Zusammenfassung 相似文献
108.
Müllner M Yuan J Weiss S Walther A Förtsch M Drechsler M Müller AH 《Journal of the American Chemical Society》2010,132(46):16587-16592
We report the preparation of water-soluble organo-silica hybrid nanotubes templated by core-shell-corona structured triblock terpolymer cylindrical polymer brushes (CPBs). The CPBs consist of a polymethacrylate backbone, a poly(tert-butyl acrylate) (PtBA) core, a poly(3-(trimethoxysilyl)propyl acrylate) (PAPTS) shell, and a poly(oligo(ethylene glycol) methacrylate) (POEGMA) corona. They were prepared via the "grafting from" strategy by the combination of two living/controlled polymerization techniques: anionic polymerization for the backbone and atom transfer radical polymerization (ATRP) for the triblock terpolymer side chains. The monomers tBA, APTS, and OEGMA were consecutively grown from the pendant ATRP initiating groups along the backbone to spatially organize the silica precursor, the trimethoxysilyl groups, into a tubular manner. The synthesized core-shell-corona structured CPBs then served as a unimolecular cylindrical template for the in situ fabrication of water-soluble organo-silica hybrid nanotubes via base-catalyzed condensation of the PAPTS shell block. The formed tubular nanostructures were characterized by transmission electron microscopy (TEM), cryogenic TEM, and atomic force microscopy. 相似文献
109.
Markus Walther Bernd M. Fischer Alex Ortner Andreas Bitzer Andreas Thoman Hanspeter Helm 《Analytical and bioanalytical chemistry》2010,397(3):1009-1017
Over the past decade, terahertz spectroscopy has evolved into a versatile tool for chemically selective sensing and imaging
applications. In particular, the potential to coherently generate and detect short, and hence, broadband terahertz pulses
led to the development of efficient and compact spectrometers for this interesting part of the electromagnetic spectrum, where
common packaging materials are transparent and many chemical compounds show characteristic absorptions. Although early proof-of-principle
demonstrations have shown the great potential of terahertz spectroscopy for sensing and imaging, the technology still often
lacks the required sensitivity and suffers from its intrinsically poor spatial resolution. In this review we discuss the current
potential of terahertz pulse spectroscopy and highlight recent technological advances geared towards both enhancing spectral
sensitivity and increasing spatial resolution. 相似文献
110.
Mata S Cortijo V Caminati W Alonso JL Sanz ME López JC Blanco S 《The journal of physical chemistry. A》2010,114(43):11393-11398
The Fourier transform microwave spectra of the hydrated forms of the tautomeric pair 2-pyridinone/2-hydroxypyridine (2PO/2HP) have been investigated in a supersonic expansion. Three hydrated species, 2PO-H?O, 2HP-H?O, and 2PO-(H?O)?, have been observed in the rotational spectrum. Each molecular complex was confidently identified by the features of the 1?N quadrupole hyperfine structure of the rotational transitions. The presence of water affects the tautomeric equilibrium -N═C(OH)- ? -NH-C(═O)-, which is shifted to the enol form for the bare molecules 2PO/2HP but to the keto tautomer for the hydrated forms. 相似文献