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71.
Ad. Carnot 《Fresenius' Journal of Analytical Chemistry》1911,50(10):640-641
Ohne Zusammenfassung 相似文献
72.
In Bell experiments, one problem is to achieve high enough photodetection to ensure that there is no possibility of describing the results via a local hidden-variable model. Using the Clauser-Horne inequality and a two-photon nonmaximally entangled state, a photodetection efficiency higher than 0.67 is necessary. Here we discuss atom-photon Bell experiments. We show that, assuming perfect detection efficiency of the atom, it is possible to perform a loophole-free atom-photon Bell experiment whenever the photodetection efficiency exceeds 0.50. 相似文献
73.
We have experimentally studied the distribution of the spatial extent of modes and the crossover from essentially single-mode to distinctly multimode behavior inside a porous gallium phosphide random laser. This system serves as a paragon for random lasers due to its exemplary high index contrast. In the multimode regime, we observed mode competition. We have measured the distribution of spectral mode spacings in our emission spectra and found level repulsion that is well described by the Gaussian orthogonal ensemble of random-matrix theory. 相似文献
74.
This work is concerned with the study of steady flows of an incompressible viscoelastic fluid of Oldroyd type, with viscosity depending on the second invariant of the rate of deformation tensor in an exterior domain. We establish a result of existence and uniqueness of strong solutions for sufficiently small data and give estimates relating these solutions to those of the corresponding generalized Newtonian fluid. 相似文献
75.
Dr. Anton Lishchynskyi Dr. Fedor M. Miloserdov Dr. Eddy Martin Dr. Jordi Benet‐Buchholz Eduardo C. Escudero‐Adán Dr. Andrey I. Konovalov Dr. Vladimir V. Grushin 《Angewandte Chemie (International ed. in English)》2015,54(50):15289-15293
First evidence for the existence of free trifluoromethyl anion CF3? has been obtained. The 3D‐caged potassium cation in [K(crypt‐222)]+ is inaccessible to CF3?, thus rendering it uncoordinated (“naked”). Ionic [K(crypt‐222)]+ CF3? has been characterized by single‐crystal X‐ray diffraction, solution NMR spectroscopy, DFT calculations, and reactivity toward electrophiles. 相似文献
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Jeroen Rintjema Dr. Wusheng Guo Dr. Eddy Martin Eduardo C. Escudero‐Adán Prof. Dr. Arjan W. Kleij 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(30):10754-10762
The chemoselective coupling of oxetanes and carbon dioxide to afford functional, heterocyclic organic compounds known as six‐membered cyclic carbonates remains a challenging topic. Here, an effective method for their synthesis relying on the use of Al catalysis is described. The catalytic reactions can be carried out with excellent selectivity for the cyclic carbonate product tolerating various (functional) groups present in the 2‐ and 3‐position(s) of the oxetane ring. The presented methodology is the first general approach towards the formation of six‐membered cyclic carbonates (6MCCs) through oxetane/CO2 coupling chemistry. Apart from a series of substituted six‐membered cyclic carbonates, also the unprecedented room‐temperature coupling of oxetanes and CO2 is disclosed giving, depending on the structural features of the substrate, a variety of five‐ and six‐membered heterocyclic products. A mechanistic rationale is presented for their formation and support for the intermediary presence of a carbonic acid derivative is given. The presented functional carbonates may hold great promise as building blocks in organic synthesis and the development of new, biodegradable polymers. 相似文献
80.
Hung Truong Ngoc Ádám Adél Varga Gábor Dudás Csilla Kele Zoltán Sipos Pál Pálinkó István 《Structural chemistry》2017,28(2):475-478
Structural Chemistry - 2-Cyano-2-(hydroxyimino)dithioacetic acid was prepared starting from cyanoacetic acid methylester via 2-cyano-2-(hydroxyimino)acetic acid methylester. Before thionation, the... 相似文献