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51.
Gharah N Chakraborty S Mukherjee AK Bhattacharyya R 《Chemical communications (Cambridge, England)》2004,(22):2630-2632
A combination of the newly synthesized and structurally characterized compound, [MoO(O2)2(saloxH)](saloxH2= salicylaldoxime) as catalyst, H2O2 as terminal oxidant and NaHCO3 as co-catalyst when stirred in CH3CN (10 cm3) at room temperature (rt) shows a very pronounced efficiency epoxidation of olefinic compounds, the method being green and economical. 相似文献
52.
R.?K.?Roy S.?K.?Mandal D.?Bhattacharyya A.?K.?PalEmail author 《The European Physical Journal B - Condensed Matter and Complex Systems》2003,34(1):25-31
Dielectric properties of silver/SiO2 nanocomposite thin films grown by high-pressure d.c. sputtering technique were studied by spectroscopic ellipsometry (300-800 nm). The dielectric behavior of the nanocomposite thin films largely depended on the particle size, its number density and the surrounding environments. The films showed semiconductor-like behavior up to a critical particle size and concentration, beyond which the films exhibited the typical surface plasmon resonance characteristics in their optical properties. The refractive index was also found to have a strong dependence on the particle size and its dispersion in the matrix. The results were found to be consistent with those obtained from UV-VIS optical absorbance data. Bruggeman effective medium theory was used to explain the experimental results.Received: 3 April 2002, Published online: 23 July 2003PACS:
78.67.-n Optical properties of nanoscale materials and structures
-
78.67.Bf Nanocrystals and nanoparticles 相似文献
53.
B. B. Bhattacharyya X. Li M. Pensky G. D. Richardson 《Annals of the Institute of Statistical Mathematics》2000,52(1):71-83
The limiting distribution of the normalized periodogram ordinate is used to test for unit roots in the first-order autoregressive model st= s-1,t+s,t-1- s-1,t-1+st. Moreover, for the sequence
n
= e
c/n
,
n
= e
d/n
of local Pitman-type alternatives, the limiting distribution of the normalized periodogram ordinate is shown to be a linear combination of two independent chi-square random variables whose coefficients depend on c and d. This result is used to tabulate the asymptotic power of a test for various values of c and d. A comparison is made between the periodogram test and a spatial domain test. 相似文献
54.
Reiter P Khoo TL Lauritsen T Lister CJ Seweryniak D Sonzogni AA Ahmad I Amzal N Bhattacharyya P Butler PA Carpenter MP Chewter AJ Cizewski JA Davids CN Ding KY Fotiades N Greene JP Greenlees PT Heinz A Henning WF Herzberg R Janssens RV Jones GD Kondev FG Korten W Leino M 《Physical review letters》2000,84(16):3542-3545
The entry distribution in angular momentum and excitation energy for the formation of 254No has been measured after the 208Pb(48Ca,2n) reaction at 215 and 219 MeV. This nucleus is populated up to spin 22Planck's over 2pi and excitation energy greater, similar6 MeV above the yrast line, with the half-maximum points of the energy distributions at approximately 5 MeV for spins between 12Planck's over 2pi and 22Planck's over 2pi. This suggests that the fission barrier is greater, similar5 MeV and that the shell-correction energy persists to high spin. 相似文献
55.
Debdulal Roy Martin Munz Sanjib Bhattacharyya P.J. Cumpson 《Applied Surface Science》2007,254(5):1394-1398
Well-defined nanostructures were written with quantum dots and magnetic nanoparticles on gold and mica surfaces using dip-pen nanolithography at room temperature. The structures with both the nanoparticles were characterised by in situ topography measurements, and the quantum dot structures were mapped by fluorescence mapping. It is demonstrated that structures of various kinds such as dots and lines can be prepared using such nanoparticles on suitably prepared surfaces. 相似文献
56.
In this paper, we apply an antiresonant reflecting layer concept in photonic crystal based waveguides. We have proposed a
thin core ARRPCW with linear waveguide carved in it and hence calculated the transmission spectra for various length of waveguide
and have shown that the longer waveguides in ARRPCW yields transmission with significantly high quality factor. Comparison
of the transmission characteristics of normal conventional planar ARROW-B waveguides & ARRPCW has also been reported. The
2D FDTD numerical modeling reveals improved transmission for various lengths of planar ARROW and ARRPCW with low losses in
long waveguides. Transmittance and quality factor are also calculated to confirm superior performance of the proposed design
of ARROW based photonic crystal waveguide. 相似文献
57.
Bhattacharyya S Fan L Vo L Labadie J 《Combinatorial chemistry & high throughput screening》2000,3(2):117-124
Amine libraries and their derivatives are important targets for high throughput synthesis because of their versatility as medicinal agents and agrochemicals. As a part of our efforts towards automated chemical library synthesis, a titanium(IV) isopropoxide mediated solution phase reductive amination protocol was successfully translated to automation on the Trident(TM) library synthesizer of Argonaut Technologies. An array of 24 secondary amines was prepared in high yield and purity from 4 primary amines and 6 carbonyl compounds. These secondary amines were further utilized in a split synthesis to generate libraries of ureas, amides and sulfonamides in solution phase on the Trident(TM). The automated runs included 192 reactions to synthesize 96 ureas in duplicate and 96 reactions to synthesize 48 amides and 48 sulfonamides. A number of polymer-assisted solution phase protocols were employed for parallel work-up and purification of the products in each step. 相似文献
58.
Excellent Performance of Few‐Layer Borocarbonitrides as Anode Materials in Lithium‐Ion Batteries
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Borocarbonitrides (BxCyNz) with a graphene‐like structure exhibit a remarkable high lithium cyclability and current rate capability. The electrochemical performance of the BxCyNz materials, synthesized by using a simple solid‐state synthesis route based on urea, was strongly dependent on the composition and surface area. Among the three compositions studied, the carbon‐rich compound B0.15C0.73N0.12 with the highest surface area showed an exceptional stability (over 100 cycles) and rate capability over widely varying current density values (0.05–1 A g?1). B0.15C0.73N0.12 has a very high specific capacity of 710 mA h g?1 at 0.05 A g?1. With the inclusion of a suitable additive in the electrolyte, the specific capacity improved drastically, recording an impressive value of nearly 900 mA h g?1 at 0.05 A g?1. It is believed that the solid–electrolyte interphase (SEI) layer at the interface of BxCyNz and electrolyte also plays a crucial role in the performance of the BxCyNz . 相似文献
59.
Christian Balischewski Dr. Biswajit Bhattacharyya Dr. Eric Sperlich Dr. Christina Günter Alkit Beqiraj Prof. Dr. Tillmann Klamroth Dr. Karsten Behrens Stefan Mies Alexandra Kelling Susanne Lubahn Lea Holtzheimer Anne Nitschke Prof. Dr. Andreas Taubert 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(64):e202201068
Fifteen N-butylpyridinium salts – five monometallic [C4Py]2[MBr4] and ten bimetallic [C4Py]2[M0.5aM0.5bBr4] (M=Co, Cu, Mn, Ni, Zn) – were synthesized, and their structures and thermal and electrochemical properties were studied. All the compounds are ionic liquids (ILs) with melting points between 64 and 101 °C. Powder and single-crystal X-ray diffraction show that all ILs are isostructural. The electrochemical stability windows of the ILs are between 2 and 3 V. The conductivities at room temperature are between 10−5 and 10−6 S cm−1. At elevated temperatures, the conductivities reach up to 10−4 S cm−1 at 70 °C. The structures and properties of the current bromide-based ILs were also compared with those of previous examples using chloride ligands, which illustrated differences and similarities between the two groups of ILs. 相似文献
60.
The thermal instability of a horizontal layer of micropolar fluid which loses heat throughout its volume at a constant rate has been considered. The influence of the various micropolar fluid parameters on the onset of convection have been analysed. It is found that heat source and heat sink have the same destabilising effect in micropolar fluid. It is observed that the horizontal dimension of the cells remains insensitive to the changes in the micropolar fluid parameters and also to the heat source parameterQ except forQ values near zero, where the change is drastic. Further, it is observed that though the vertical component of velocity and the curl of microrotation do not vanish anywhere between the two boundaries forQ=0, they vanish at a point nearer to the lower boundary even for a small change in theQ value. 相似文献