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排序方式: 共有148条查询结果,搜索用时 15 毫秒
1.
The synthesis and properties of perchlorobi-9-fluorenylidene, a highly twisted ethylene, are reported. It is a diamagnetic chlorocarbon. 相似文献
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Ballester P Costa A Castilla AM Deyà PM Frontera A Gomila RM Hunter CA 《Chemistry (Weinheim an der Bergstrasse, Germany)》2005,11(7):2196-2206
Three isomeric zinc bisporphyrins have been prepared by covalently linking together two aminoporphyrins with an isophthalic acid derivative. The porphyrins differ in the substitution pattern on the meso phenyl groups, that is, ortho, meta, or para. Titrations carried out by UV-visible and 1H NMR spectroscopy have been used to map out the stabilities and the stoichiometries of the complexes formed with 1,4-diazabicyclo[2.2.2]octane (DABCO) in chloroform. The ortho- and meta-substituted bisporphyrins form 1:1 intramolecular sandwich complexes. The para-substituted bisporphyrin cannot adopt the cofacial conformation required for this type of complex and forms a higher order 2:2 intermolecular assembly, which is stable over a wide range of DABCO concentrations. 相似文献
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We present a method to implement ultrafast two-qubit gates valid for the ultrastrong coupling and deep strong coupling regimes of light-matter interaction, considering state-of-the-art circuit quantum electrodynamics technology. Our proposal includes a suitable qubit architecture and is based on a four-step sequential displacement of the intracavity field, operating at a time proportional to the inverse of the resonator frequency. Through ab?initio calculations, we show that these quantum gates can be performed at subnanosecond time scales while keeping a fidelity above 99%. 相似文献
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The oxidation of 2,3,5,6-tetrachloro--phenylenediamine with Cl2 or Br2 in CCl4 containing I2 affords unusual quinoniminium salts displaying remarkable chemical behaviour. 相似文献
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Fantuzzi G Pengo P Gomila R Ballester P Hunter CA Pasquato L Scrimin P 《Chemical communications (Cambridge, England)》2003,(8):1004-1005
N-Methylimidazole-functionalized gold nanoparticles behave as multivalent ligands for porphyrin arrays with an increase in binding strength of up to three order of magnitude with respect to a monovalent system. 相似文献
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The main objective of this paper is to study and describe the hypercentre of a finite group associated with saturated formations, in terms of some subgroup embedding properties related to permutability. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
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Ballester P Capó M Costa A Deyà PM Frontera A Gomila R 《Molecules (Basel, Switzerland)》2004,9(5):278-286
A dinuclear self-assembled cationic macrocycle based on Pt(II)-N(pyridine) coordinative bonds and having competitive triflate anions, as metal counterions, is used in the construction of [2]rotaxane and [2]pseudorotaxane architectures assisted by hydrogen bonding. The kinetic lability of the Pt(II)-N(pyridine) coordinative bond controls the dynamics of the [2]rotaxane. 相似文献