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61.
Zhenghai Yang Chao He Srinivas Doddipatla Vladislav S. Krasnoukhov Prof. Valeriy N. Azyazov Prof. Alexander M. Mebel Prof. Ralf I. Kaiser 《Chemphyschem》2020,21(17):1898-1904
The methylgermylene species (HGeCH3; X1A′) has been synthesized via the bimolecular gas phase reaction of ground state methylidyne radicals (CH) with germane (GeH4) under single collision conditions in crossed molecular beams experiments. Augmented by electronic structure calculations, this elementary reaction was found to proceed through barrierless insertion of the methylidyne radical in one of the four germanium-hydrogen bonds on the doublet potential energy surface yielding the germylmethyl (CH2GeH3; X2A′) collision complex. This insertion is followed by a hydrogen shift from germanium to carbon and unimolecular decomposition of the methylgermyl (GeH2CH3; X2A′) intermediate by atomic hydrogen elimination leading to singlet methylgermylene (HGeCH3; X1A′). Our investigation provides a glimpse at the largely unknown reaction dynamics and isomerization processes of the carbon-germanium system, which are quite distinct from those of the isovalent carbon system thus providing insights into the intriguing chemical bonding of organo germanium species on the most fundamental, microscopic level. 相似文献
62.
We have undertaken the molecular imprinting of Leu5-enkephalin, and derivatives related to this endogenous neuropeptide, in highly cross-linked methacrylic acid/ethylene dimethacrylate copolymers. The underivatized enkephalin peptide yielded polymers with poor recognition abilities, since the imprinting of this compound had to be performed using dimethyl sulfoxide, which was found to interfere with the imprint inducement, as the solvent of polymerisation. In order to circumvent this problem, the amino- and carboxy-protected derivatives Boc-Leu5-enkephalin and Leu5-enkephalin anilide, which are soluble in apolar solvents, were investigated as alternative imprint molecules. Both compounds led to polymers which are highly specific for the imprint species. The anilide derivative was shown to be a good substitute for the free peptide since the resultant polymers showed efficient recognition of the parent enkephalin structure. 相似文献
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The quantum group IGL
q
(N), the inhomogenization of GL
q
(N), is formulated with
-matrices. Theq-deformed universal enveloping algebra is constructed as the algebra of regular functionals in this formulation and contains the partial derivatives of the covariant differential calculus on the quantum space. 相似文献
68.
Menzel D Fastl H Graf R Hellbrück J 《The Journal of the Acoustical Society of America》2008,123(5):2477-2479
This experiment investigates the effect of images of differently colored sports cars on the loudness of a simultaneously perceived car sound. Still images of a sports car, colored in red, light green, blue, and dark green, were displayed to subjects during a magnitude estimation task. The sound of an accelerating sports car was used as a stimulus. Statistical analysis suggests that the color of the visual stimulus may have a small influence on loudness judgments. The observed loudness differences are generally equivalent to a change in sound level of about 1 dB, with maximum individual differences of up to 3 dB. 相似文献
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