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51.
Sunil K. Singhal Veeresh Kumar K. Stalin Amit Choudhary Satish Teotia Gade B. Reddy Rakesh B. Mathur Surinder P. Singh Renu Pasricha 《Particle & Particle Systems Characterization》2013,30(5):445-452
Synergetic cooperation of individual components of the nanocomposites (NCs) is responsible for their novel properties that lead to various technological applications. A simple chemical process depicting the deposition of functionalized gold nanoparticles on the surface of boron nitride nanosheets (BNNSs) in solution is reported. The structure, chemical composition, and optical properties of nanosheets are systematically studied. The deposition of Au nanoparticles on BNNS (BNNSAu) results in plasmonic band modulation, thus altering the optoelectronic properties of BNNSs. The intense surface plasmon absorption band of BNNSAu is narrowed and red‐shifted relative to the absorption band of as synthesized monometallic BNNSs. The observations reflect the strong interfacial interaction between BNNS and Au nanoparticles. This approach constitutes a basis for a simple process leading to the preparation of functionalized BNNSs and their utilization as nanoscale templates for assembly and integration with other nanoscale materials for futuristic optoelectronic devices. 相似文献
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Renu Tripathi G.S. Pati M. Messall K. Salit M.S. Shahriar 《Optics Communications》2006,266(2):604-608
We report on experimental observation of electromagnetically induced transparency and slow-light (vg ≈ c/607) in atomic sodium vapor, as a potential medium for a recently proposed experiment on slow-light enhanced relative rotation sensing [Shahriar et al. Phys. Rev. Lett. (submitted for publication), http://arxiv.org/abs/quant-ph/0505192.]. We have performed an interferometric measurement of the index variation associated with a two-photon resonance to estimate the dispersion characteristics of the medium that are relevant to the slow-light based rotation sensing scheme. We also show that the presence of counter-propagating pump beams in an optical Sagnac loop produces a backward optical phase conjugation beam that can generate spurious signals, which may complicate the measurement of small rotations in the slow-light enhanced gyroscope. We identify techniques for overcoming this constraint. Conclusions reached from the results presented here will pave the way for designing and carrying out an experiment that will demonstrate the slow-light induced enhancement of rotation sensing. 相似文献
54.
Reactions of copper(I) halides (Cl, Br, I) with 1‐methyl‐1, 3‐imidazoline‐2‐thione (mimzSH) in 1 : 2 molar ratio yielded sulfur‐bridged dinuclear [Cu2X2(μ‐S‐mimzSH)2(η1‐S‐mimzSH)2] (X = I, 1 , Br, 2 ; Cl, 3 ) complexes. Copper(I) iodide with 1,3‐imidazoline‐2‐thione (imzSH2) and Ph3P in 1 : 1 : 1 molar ratio has also formed a sulfur‐bridged dinuclear [Cu2I2(μ‐S‐imzSH2)2(PPh3)2] ( 4 ) complex. The central Cu(μ‐S)2Cu cores form parallelograms with unequal Cu–S bond distances {2.324(2), 2.454(3) Å} ( 1 ); {2.3118(6), 2.5098(6) Å} ( 2 ); {2.3075(4), 2.5218(4) Å} ( 3 ); {2.3711(8), 2.4473(8) Å} ( 4 ). The Cu···Cu separations, 2.759–2.877Å in complexes 1 – 3 are much shorter than 3.3446Å in complex 4 . The weak intermolecular interactions {H2CH···S# ( 2 ); CH···Cl# ( 3 ); NH···I# ( 4 )} between dimeric units in complexes 2 – 4 lead to the formation of linear 1D polymers. 相似文献
55.
Summary The formation of near square planar mixed ligand CuII complexes with diethyldithiocarbamate (dtc) as one of the ligands and 8-hydroxyquinolinate (Hy) or salicylaldehydate (Sal) as the second ligand by exchange reactions, has been detected by e.p.r. spectroscopy. The concentrations of the mixed ligand complexes in the reaction mixtures are small compared to those of the reactants. Six different tests were used to identify the m1=3/2,63Cu hyperfine transition of the near square planar complexes, based upon the relative concentrations of the different CuII species in the reaction mixture, ligand hyperfine structures, the minium linewidths observed in a temperature dependent study and the isotropic g0 estimated from the e.p.r. spectra in solution. 相似文献
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It is shown by Rao and Rao that certain geometric properties characterize the line graph of a BIB design with parameters b, v, r, k, 1, provided r - 2k + 1 < 0. If r = k + 1, and , a characterization of the line graph of a finite affine plane is obtained. If r - 2k + 1 = 0, the only possible value for k is 2 and consequently r = k + 1 resulting in the case of the line graph of a finite affine plane. It is shown here that if r = k + 1 and k = 2, there are exactly seven other non-isomorphic graphs with those properties which are not the line graph of a finite affine plane and these are the only cubic graphs on twelve vertices with no quadrilaterals. 相似文献
58.
Synthesis of 3-(′, 1′-dimethylallyl)herniarin and 3-(′, 1′-dimethylallyl)desmothosyherniarin has been carried out by a versatile route. 相似文献
59.
Aamodt K Abelev B Quintana AA Adamová D Adare AM Aggarwal MM Rinella GA Agocs AG Salazar SA Ahammed Z Masoodi AA Ahmad N Ahn SU Akindinov A Aleksandrov D Alessandro B Molina RA Alici A Alkin A Aviña EA Alt T Altini V Altinpinar S Altsybeev I Andrei C Andronic A Anguelov V Anson C Antičić T Antinori F Antonioli P Aphecetche L Appelshäuser H Arbor N Arcelli S Arend A Armesto N Arnaldi R Aronsson T Arsene IC Asryan A Augustinus A Averbeck R Awes TC Aystö J Azmi MD Bach M Badalà A Baek YW 《Physical review letters》2010,105(25):252301
The first measurement of the charged-particle multiplicity density at midrapidity in Pb-Pb collisions at a center-of-mass energy per nucleon pair √ S NN = 2.76 TeV is presented. For an event sample corresponding to the most central 5% of the hadronic cross section, the pseudorapidity density of primary charged particles at midrapidity is 1584 ± 4(stat) ± 76(syst), which corresponds to 8.3 ± 0.4(syst) per participating nucleon pair. This represents an increase of about a factor 1.9 relative to pp collisions at similar collision energies, and about a factor 2.2 to central Au-Au collisions at √ S NN = 2.76 TeV. This measurement provides the first experimental constraint for models of nucleus-nucleus collisions at LHC energies. 相似文献
60.
Aamodt K Abelev B Quintana AA Adamová D Adare AM Aggarwal MM Rinella GA Agocs AG Salazar SA Ahammed Z Masoodi AA Ahmad N Ahn SU Akindinov A Aleksandrov D Alessandro B Molina RA Alici A Alkin A Aviña EA Alt T Altini V Altinpinar S Altsybeev I Andrei C Andronic A Anguelov V Anson C Antičić T Antinori F Antonioli P Aphecetche L Appelshäuser H Arbor N Arcelli S Arend A Armesto N Arnaldi R Aronsson T Arsene IC Asryan A Augustinus A Averbeck R Awes TC Aystö J Azmi MD Bach M Badalà A Baek YW 《Physical review letters》2010,105(25):252302
We report the first measurement of charged particle elliptic flow in Pb-Pb collisions at sqrt[S(NN)] =2.76 TeV with the ALICE detector at the CERN Large Hadron Collider. The measurement is performed in the central pseudorapidity region (|η|<0.8) and transverse momentum range 0.2
相似文献