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161.
An ultra-high speed, time-resolved particle image velocimetry (PIV) system is developed to measure velocity fields created
by explosive detonators. When initiated into a gas, the detonators generate blast waves that propagate outwards from the origin
of initiation at supersonic speeds. The PIV system consists of a custom eight-pulse Nd:YAG laser system and an ultra-high
speed camera system comprising four dual-frame CCD cameras optically combined to share a single optic axis. The system is
capable of sampling the flow field four times at up to 333 MHz or eight times at up to 8 MHz. System development is discussed,
and preliminary application to the complex flow behind the blast wave from an exploding bridge wire detonator is demonstrated. 相似文献
162.
Back Cover: Supramolecular Wiring of Benzo‐1,3‐chalcogenazoles through Programmed Chalcogen Bonding Interactions (Chem. Eur. J. 16/2016)
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163.
164.
Supramolecular Wiring of Benzo‐1,3‐chalcogenazoles through Programmed Chalcogen Bonding Interactions
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Dr. Adrian Kremer Dr. Andrea Fermi Nicolas Biot Prof. Johan Wouters Prof. Dr. Davide Bonifazi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(16):5665-5675
The high‐yielding synthesis of 2‐substituted benzo‐1,3‐tellurazoles and benzo‐1,3‐selenazoles through a dehydrative cyclization reaction has been reported, giving access to a large variety of benzo‐1,3‐chalcogenazoles. Exceptionally, these aromatic heterocycles proved to be very stable and thus very handy to form controlled solid‐state organizations in which wire‐like polymeric structures are formed through secondary N???Y bonding interactions (SBIs) engaging the chalcogen (Y=Se or Te) and nitrogen atoms. In particular, it has been shown that the recognition properties of the chalcogen centre at the solid state could be programmed by selectively barring one of its σ‐holes through a combination of electronic and steric effects exerted by the substituent at the 2‐position. As predicted by the electrostatic potential surfaces calculated by quantum chemical modelling, the pyridyl groups revealed to be the stronger chalcogen bonding acceptors, and thus the best ligand candidate for programming the molecular organization at the solid state. In contrast, the thiophenyl group is an unsuitable substituent for establishing SBIs in this molecular system as it gives rise to chalcogen–chalcogen repulsion. The weaker chalcogen donor properties of the Se analogues trigger the formation of feeble N???Se contacts, which are manifested in similar solid‐state polymers featuring longer nitrogen–chalcogen distances. 相似文献
165.
Theodore Flack Thibaut Constantin Sylvain Penasse Dr. Jérôme Dejeu Béatrice Gennaro Dr. Muriel Jourdan Aurélien Laguerre Marc Pirrotta Dr. David Monchaud Dr. Nicolas Spinelli Prof. Eric Defrancq 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(5):1760-1767
A water‐soluble template‐assembled synthetic G‐quartet (TASQ) based on the use of a macrocyclodecapeptide scaffold was designed to display stable intramolecular folds alone in solution. The preformation of the guanine quartet, demonstrated by NMR and CD investigations, results in enhanced peroxidase‐type biocatalytic activities and improved quadruplex‐interacting properties. Comparison of its DNAzyme‐boosting properties with the ones of previously published TASQ revealed that, nowadays, it is the best DNAzyme‐boosting agent. 相似文献
166.
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168.
Dimitris Arabadjis Constantin Papaodysseus Panayiotis Rousopoulos Michalis Panagopoulos 《Journal of Applied Mathematics and Computing》2010,34(1-2):81-100
In this paper two new theorems are proved in association with the problem of matching three dimensional solid bodies. Rigorous mathematical criteria are given in order to test if two such bodies actually match in a certain position. Since this problem finds important application to the actual problem of reassembling fragmented objects e.g. archaeological, special care is taken to account for small gaps between matching fragments and fuzziness of the matching parameters. 相似文献
169.
Kreibik Stefan Coman Virginia Mruoiu Constantin Mihilescu Gheorghe 《平面色谱法杂志一现代薄层色谱法》2001,14(4):246-251
JPC – Journal of Planar Chromatography – Modern TLC - Some of the physical properties of dielectric liquids are influenced by electric fields. Interesting results were obtained in this... 相似文献
170.
We present the results of a numerical investigation of percolation properties in a version of the classical Heisenberg model. In particular we study the percolation properties of the subsets of the lattice corresponding to equatorial strips of the target manifold
2. As shown by us several years ago, this is relevant for the existence of a massless phase of the model. Our investigation yields strong evidence that such a massless phase does indeed exits. It is further shown that this result implies lack of asymptotic freedom in the massive continuum limit. A heuristic estimate of the transition temperature is given which is consistent with the numerical data. 相似文献