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Wireless Personal Communications - The Invisible Internet Project (I2P) as a secure protocol uses robust mechanisms and strong algorithms to reinforce the security and the anonymity of the...  相似文献   
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A copper(II)‐catalysed approach to oxindoles, thio‐oxindoles, 3,4‐dihydro‐1H‐quinolin‐2‐ones, and 1,2,3,4‐tetrahydroquinolines via formal C?H, Ar?H coupling is described. In a new variant, copper(II) 2‐ethylhexanoate has been identified as an inexpensive and efficient catalyst for this transformation, which utilises atmospheric oxygen as the re‐oxidant.  相似文献   
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Wireless Networks - In Vehicular Ad-Hoc Networks, a link failure may occur due to non-optimal channel conditions, congestion or node mobility which causes data loss. Common proposed approaches try...  相似文献   
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Within the band gap of a semiconductor no electronic propagating states are allowed, but there exist evanescent states which govern charge transport such as tunneling. In this Letter, we address the issue of their spin dependence in III-V semiconductors. Taking into account the spin-orbit interaction, we treat the problem using a k . p 14 x 14 Hamiltonian that we numerically compute for GaAs. Our results show that the removed spin degeneracy in the band gap can lead to giant energy splittings and induces forbidden zones in space where evanescent states are suppressed.  相似文献   
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An asymmetrical ferromagnetic cobalt bilayer (18 nm Au/0.8 nm Co/2.2 nm Au/1.3 nm Co/1.5 nm Au) operates as a self-calibrated spin polarimeter with a high spin selectivity for free electrons injected at a few eV above the Fermi level. We present the analysis of transmitted currents as a function of the incident energy, based on a model of spin polarization dilution into the first gold layer and ballistic transport close to the vacuum level throughout the sample.  相似文献   
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Application of radical cross-dehydrogenative coupling (CDC) procedures to prepare a range of novel spirocyclic oxindoles and to a formal total synthesis of the vasopressin V2 receptor antagonist Satavaptan is reported. The key step involves a copper-mediated oxidative cyclisation of a simple linear anilide precursor to give the spirocyclic oxindole core. This synthetic approach was also used to prepare novel Satavaptan scaffolds and analogues.  相似文献   
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A practical and efficient entry to spirocyclic oxindoles from readily accessible anilide precursors, using only catalytic amounts of an inexpensive copper salt together with air as the sole re-oxidant, is described. In addition to providing access to a broad range of spiro-oxindole products, the utility of this method is demonstrated in a formal synthesis of the natural product, horsfiline.  相似文献   
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