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31.
The 1,6,7,12,13,18‐hexaazatrinaphthylene (HATN) complex [(Et2Zn)3(μ3‐HATN)] was synthesized and characterized by IR spectroscopy, UV/Vis spectroscopy, elemental analysis and ESI‐MS spectrometry. Attempts to prepare ZnCl2 complexes of HATN leads only to the mononuclear [(Cl2Zn)(HATN)] derivative, characterized by X‐ray diffraction, IR‐ and UV/Vis‐spectroscopy as well as ESI‐MS spectrometry. The bright red 2,2′‐bipyridine (bipy) complex [(Et2Zn)(bipy)] ( 1 ) was synthesized and characterized by X‐ray diffraction and NMR spectroscopy. The UV/Vis‐spectra of the HATN‐complexes show absorptions in regions of far longer wavelengths than the corresponding 2,2′‐bipyridine or 1,10‐phenantroline complexes. Consequently the π*‐LUMO of HATN ( 5 ) is lower in energy than the π*‐LUMO of 2,2′‐bipyridine ( 2 ) or 1,10‐phenanthroline (phen). 相似文献
32.
The neutral molecules nitrosoformaldehyde ( 1a ), 1-nitrosoacetaldehyde ( 1b ), and 2,2,2-trifluoro-1-nitrosoacetaldehyde ( 1c ) have been generated and detected by neutralization-reionization mass spectrometry (NR-MS). 相似文献
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Detlev W. Hoffmann 《manuscripta mathematica》1994,85(1):109-118
Summary LetF be a field with a non-trivial valuation υ:F→ℝ∪{+∞}. To any power series in one variable overF one can associate a Newton polygon with respect to this valuation. LetN
1 andN
2 be polygons which arise as Newton polygons of power series overF. We determine the set of polygonsN with the property that there exist power seriesf
i
with respective Newton polygonN
i
,i=1,2, such that the productf
1
f
2 has Newton polygonN.
Supported by a grant from the DFG
This article was processed by the author using the LATEX style filepljour1 from Springer-Verlag. 相似文献
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In this work, a microfluidic free-flow electrophoresis device with a novel approach for preventing gas bubbles from entering the separation area is presented. This is achieved by integrating partitioning bars to reduce the channel depth between electrode channels and separation chamber in order to obtain electrical contact and simultaneously prevent bubbles from entering the separation area. The three-layer sandwich chip features a reusable carrier plate with integrated ports for fluidic connection combined with a softlithographically cast microfluidic PDMS layer and a sealing glass slide. This design allows for a straightforward and rapid chip prototyping process. The performance of the device is demonstrated by free-flow zone electrophoretic separations of fluorescent dye mixtures as well as by the separation of labeled amines and amino acids with separation voltages up to 297 V. 相似文献
38.
Short R Carta M Bezzu CG Fritsch D Kariuki BM McKeown NB 《Chemical communications (Cambridge, England)》2011,47(24):6822-6824
Microporous polymers derived from the 1,2- and 1,4-regioisomers of di(3',4'-dihydroxyphenyl)tetraphenylbenzene have very different properties with the former being composed predominantly of cyclic oligomers whereas the latter is of high molar mass suitable for the formation of robust solvent-cast films of high gas permeability. 相似文献
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