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51.
Dr. Weinan Xing Dr. Shengming Yin Dr. Wenguang Tu Dr. Guanyu Liu Dr. Shuyang Wu Dr. Haojing Wang Prof. Markus Kraft Dr. Guangyu Wu Prof. Rong Xu 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(3):1187-1191
A simple solvent ligation effect was successfully used to disrupt the growth of a model compound, Fe[(OH)(O3P(CH2)2CO2H)]⋅H2O (MIL-37), into an extended 2D structure by replacing water with dimethylformamide (DMF) as the solvent during the synthesis. Owing to the lack of −OH group, which provides the corner-sharing (binding) oxygen atoms for the octahedra, an amorphous and porous structure is formed. When Fe3+ is partially replaced by Ni2+, the amorphous structure remains and the resultant binary metal catalyst displays excellent photocatalytic oxygen evolution activity with almost 100 % yield achieved under visible light irradiation using [Ru(bpy)3]2+ as the photosensitizer. This study opens up new possibilities of using the simple solvent effect to synthesize high surface area metal phosphonates for catalytic and other applications. 相似文献
52.
Weinan Xing Shengming Yin Wenguang Tu Guanyu Liu Shuyang Wu Haojing Wang Markus Kraft Guangyu Wu Rong Xu 《Angewandte Chemie (International ed. in English)》2020,59(3):1171-1175
A simple solvent ligation effect was successfully used to disrupt the growth of a model compound, Fe[(OH)(O3P(CH2)2CO2H)]?H2O (MIL‐37), into an extended 2D structure by replacing water with dimethylformamide (DMF) as the solvent during the synthesis. Owing to the lack of ?OH group, which provides the corner‐sharing (binding) oxygen atoms for the octahedra, an amorphous and porous structure is formed. When Fe3+ is partially replaced by Ni2+, the amorphous structure remains and the resultant binary metal catalyst displays excellent photocatalytic oxygen evolution activity with almost 100 % yield achieved under visible light irradiation using [Ru(bpy)3]2+ as the photosensitizer. This study opens up new possibilities of using the simple solvent effect to synthesize high surface area metal phosphonates for catalytic and other applications. 相似文献
53.
Nicolas Armanino Julie Charpentier Felix Flachsmann Andreas Goeke Marc Liniger Philip Kraft 《Angewandte Chemie (International ed. in English)》2020,59(38):16310-16344
This review is the sequel to the 2000 report on the recent advances in the chemistry of odorants and it summarizes the developments in fragrance chemistry over the past 20 years. Following the olfactory spectrum set out in that report, trendsetting so‐called captive odorants (patent‐protected ingredients unavailable to the market) are presented according to the main odor families: “fruity”, “marine”, “green”, “floral”, “spicy”, “woody”, “amber”, and “musky”. The design of odorants, their chemical synthesis, and their use in modern perfumery are illustrated with prominent examples. Featured are new fruity odorants that provide signature in the top note, as well as precursor technology. In the green domain, focus is on leafy notes and green pear. New benzodioxepines and benzodioxoles have modernized the marine family and required a revision of the existing olfactophore models. The replacement of Lilial and Lyral kept the industry busy in the floral domain with a plethora of new “muguets”. There was continued activity in the domain of rose odorants, especially in the area of rose ketones. Biotechnology became significant, for example, with Clearwood and Ambrofix, and the principal odorants of vetiver oil in the woody family have been found. Fourth and fifth families of musk odorants were also discovered and populated. Thus, new avenues for further explorations into fragrance chemistry have been opened. 相似文献
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This paper relates recursive utility in continuous time to its discrete-time origins and provides an alternative to the approach presented in Duffie and Epstein (Econometrica 60:353–394, 1992), who define recursive utility in continuous time via backward stochastic differential equations (stochastic differential utility). We show that the notion of Gâteaux differentiability of certainty equivalents used in their paper has to be replaced by a different concept. Our approach allows us to address the important issue of normalization of aggregators in non-Brownian settings. We show that normalization is always feasible if the certainty equivalent of the aggregator is of the expected utility type. Conversely, we prove that in general Lévy frameworks this is essentially also necessary, i.e. aggregators that are not of the expected utility type cannot be normalized in general. Besides, for these settings we clarify the relationship of our approach to stochastic differential utility and, finally, establish dynamic programming results. 相似文献
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Kraft P Bajgrowicz JA Denis C Fráter G 《Angewandte Chemie (International ed. in English)》2000,39(17):2963
The cover picture shows, on the lip of Oncidium tigrinum La Llave et Lex., the superposition of beta-ionone and a tailor-made bicyclo[6.4.0]dodecene. The structural similarity of the two molecules accounts for their close odors. beta-Ionone is present in the scent of the depicted tropical orchid at the unusually high level of 14.5 %. An overview of the olfactory spectrum is shown in the background. More on scents and their molecules can be found in the review of P. Kraft et al. on p. 2980 ff. 相似文献
59.
A CD(3) group close in space to (but many bonds distant from) a carbon atom A causes a substituent effect on the chemical shift of C(A) that is algebraically smaller than the effect of a CH(3) group, in agreement with the notion of shorter C-D relative to C-H bonds. Hence, the deuterium isotope effect of CD(3) upon delta(C(A)) is shielding when the substituent effect is deshielding, and vice versa. 相似文献
60.