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61.
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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64.
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
65.
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
66.
Experimental results for the measurements of hydrodynamic permeability, electroosmotic velocity and streaming potential of water and dioxane—water (DH2O) mixtures (10, 20, 30 and 40% by mass of dioxane) using a pyrex sintered disc (G2) impregnated with cellulose acetate at 30°C and at voltages up to 40 V are reported. The data have been analysed in the light of non-equilibrium thermodynamics. Onsager's reciprocity relation for all compositions of aqueous—dioxane has been found to hold true. It has been found that the concentration dependence of the phenomenological coefficients conform to the Spiegler's frictional model. Efficiencies of electrokinetic energy conversion, i.e. electroosmosis and streaming potential, have been determined and the results are in accordance with the theory of non-equilibrium thermodynamics. The maximum value of the efficiency of energy conversion for both the modes has been found to be independent of the input force. Membrane characteristics such as pore radius and number of pores have been determined, whereas the membrane—permeant interface is characterised in term of the zeta potential. 相似文献
67.
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
68.
Nisha Bansal Sarvesh Kumar Deepti Pratap Saif Ahmad Khan R.S. Chauhan 《辐射效应与固体损伤》2013,168(10):855-861
The present study is carried out for the investigation of energetic ion beam mixing in the Bi/Ge system, induced by electronic excitation. The system Ge/Bi/C was deposited on Si substrate at room temperature in the high vacuum deposition system and irradiated using Au ions of 120?MeV at the fluences 1?×?1013, 5?×?1013 and 1?×?1014?ions/cm2. The top layer of carbon was deposited as the protecting layer to avoid oxidation. The swift heavy ions (SHI)-induced interface mixing was studied by Rutherford backscattering spectroscopy (RBS) for depth profiles and compositions, grazing incidence X-ray diffraction (GIXRD) for phase identification and atomic force microscopy (AFM) for surface roughness. We have calculated the mixing rate, mixing efficiency and inter-diffusion coefficient for the Bi/Ge system. We observed that the thickness of the mixed region increased with increasing fluence. In the GIXRD pattern, no new crystalline phase formation was observed after irradiation, the mixed region may be in an amorphous form. The mixing effect is explained in the framework of the thermal spike model. 相似文献
69.
Marcela R. Beltrán Fernando Buendía Zamudio Vikas Chauhan Prasenjit Sen Haopeng Wang Yeon Jae Ko Kit Bowen 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2013,67(3):1-8
We present an analysis of Na-He collisional profiles at high density and very low temperature in a unified line shape semi-classical theory which contains the impact as well the quasistatic limits. Clearly understanding the variation of shape of the two fine-structure components of the 3s?3p line with increasing helium density allows us to understand experimental spectra of a Na atom attached to He nanodroplets. We compare our collisional approach to path integral Monte Carlo calculations using the same ab initio Na-He molecular potentials. 相似文献
70.
Renu Bala Poonam Kumari Sumit Sood Harshita Phougat Anil Kumar Karan Singh 《Journal of heterocyclic chemistry》2019,56(6):1787-1793
The conversion of aldehydes into carboxylic acids using oxidizing agents is a common protocol in transformation chemistry. An efficient oxidation strategy of transformation of pyrazole‐4‐aldehydes to the corresponding acids using vanadium catalysts in the presence of 30% H2O2 as an oxidant is described. The catalytic technology was successfully applied to a range of various 4‐formylpyrazoles, and plausible mechanism is also discussed. 相似文献