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81.
82.
A novel optical burst switching (OBS) high speed network architecture has been proposed. To verify its feasibility and evaluate its performance, just-enough-time (JET) signaling has been considered as a high performance protocol. In the proposed architecture, to avoid burst losses, firstly, a short-prior- confirmation-packet (SPCP) is sent over the control channel that simulates the events that the actual packet will experience. Once SPCP detects a drop at any of the intermediate nodes, the actual packet is not sent but the process repeats. In order to increase network utilization, cost effectiveness and to overcome some limitations of conventional OBS, inherent codes (e.g., orthogonal optical codes (OOC)), which are codified only in intensity, has been used. Through simulations, it shows that a decrease in burst loss probability, cost effectiveness and a gain in processing time are obtained when optical label processing is used as compared with electronic processing. 相似文献
83.
84.
Hanna TA Ghosh AK Ibarra C Zakharov LN Rheingold AL Watson WH 《Inorganic chemistry》2004,43(24):7567-7569
Molybdenum monooxo compoundsMoO(OAr)4-nCln (n=0-2, Ar=2,6-Me2C6H3 or 2,6-i-Pr2C6H3) have been synthesized starting from the dioxo precursor MoO2Cl2. The complexes are characterized spectroscopically and by X-ray diffraction. The formation mechanism likely involves phenol precoordination followed by addition across the Mo=O bond. 相似文献
85.
Novel enediynyl amino acids and peptides 3 and 5-8 were synthesized and their thermal reactivity towards Bergman cyclization studied and compared with the earlier reported amino acid 4, which demonstrated, for the first time, the effect of H-bonding and electrostatic interactions in lowering the activation energy of Bergman cyclization. 相似文献
86.
87.
A novel azophenol-quinazoline dyad 1 has been designed, synthesized and demonstrated as an efficient reversible multichannel pH indicator through distinct signalling in aqueous media. Owing to the competence between highly fluorescent quinazoline moiety and a well known fluorescence quencher diazo group, dyad 1 is moderately fluorescent in nature. Under acidic conditions 1 displays diverse fluorogenic changes (blue emission at pH 4.25; green at pH 1.80) while under basic condition (pH 11.80) chromogenic changes were observed. 相似文献
88.
Alvaro M Atienzar P de la Cruz P Delgado JL Troiani V Garcia H Langa F Palkar A Echegoyen L 《Journal of the American Chemical Society》2006,128(20):6626-6635
A soluble, functionalized Py-SWNT has been synthesized and characterized by solution (1)H and (13)C NMR, FT-Raman, and electron microscopy. Experimental data indicate that Py-SWNT has short tubes with pentyl esters at the tips and pyridyl isoxazolino units along the walls. The synthesis of Py-SWNT is based on a 1,3-dipolar cycloaddition of a nitrile oxide on the SWNT walls, similar to 1,3-dipolar cycloadditions that are common for fullerene functionalization. The resulting Py-SWNT forms a complex with a zinc porphyrin (ZnPor) in a way similar to that reported for pyridyl-functionalized [60]-fullerenes. Formation of this metal-ligand complex was firmly established by a detailed electrochemical study. However, in contrast to the behavior observed for the ZnPor/Py-C(60) complex, photochemical excitation of the complex between ZnPor/Py-SWNT does not lead to electron transfer with the generation of charge-separated states. Fluorescence and laser flash studies indicate that the main process is energy transfer from the singlet ZnPor excited state to the Py-SWNT with observation of emission from Py-SWNT. Triplet ZnPor excited-state quenching by Py-SWNT is only observed in polar solvents such as DMF, but not in benzonitrile. 相似文献
89.
Amit S. Nagare Arpan Manna Pramod D. Sonawane Anil Kumar 《Journal of Physical Organic Chemistry》2015,28(11):665-673
Prevailing classification of salts based on their effect in solubility and stability of proteins in aqueous solution predicts that tetraalkylammonium salts, guanidinium chloride (GnCl), LiClO4 act as salting‐in (S/I) and LiCl, NaCl act as salting‐out (S/O) in aqueous conditions. In the same context the behaviour of GnCl, LiClO4 and LiCl are contradictory in polar solvents like ethylene glycol and formamide. In these solvents, expected salt effect shows just opposite nature from their usual expectation. However, in the aqueous solution salts like tetraalkylammonium halide (R4NX, R = alkyl group, X = Br group) behave like salting‐in salts. The physicochemical origin of the salting in effect of R4NX type of salts has been discussed elaborately in the present work. The role of cations in terms of substitution of various alkyl groups on R4NX has been systematically presented here on the basis of experimental kinetic and thermodynamic studies. The abnormal behaviour of R4NX salts in aqueous solution has also been explained by the Setschenov equation (ks) and Δμsolvation values, which highlights their individual nature out of common properties of R4NX. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
90.
Gyanaranjan Prusty Amit K. Guria Indranil Mondal Anirban Dutta Dr. Ujjwal Pal Dr. Narayan Pradhan 《Angewandte Chemie (International ed. in English)》2016,55(8):2705-2708
A generic modular synthetic strategy for the fabrication of a series of binary‐ternary group II‐VI and group I‐III‐VI coupled semiconductor nano‐heterostructures is reported. Using Ag2Se nanocrystals first as a catalyst and then as sacrificial seeds, four dual semiconductor heterostructures were designed with similar shapes: CdSe‐AgInSe2, CdSe‐AgGaSe2, ZnSe‐AgInSe2, and ZnSe‐AgGaSe2. Among these, dispersive type‐II heterostructures are further explored for photocatalytic hydrogen evolution from water and these are observed to be superior catalysts than the binary or ternary semi‐conductors. Details of the chemistry of this modular synthesis have been studied and the photophysical processes involved in catalysis are investigated. 相似文献