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131.
A. Majumder 《Acta Physica Hungarica A》2006,27(1):97-104
Two-particle correlations within a single jet produced in deeply inelastic scattering (DIS) off a large nucleus as well as in heavy-ion collisions are studied. This is performed within the framework of the medium modified dihadron fragmentation functions. The modification occurs due to gluon bremsstrahlung induced by multiple scattering. The modified fragmentation functions for dihadrons are found to follow closely that of single hadrons leading to a weak nuclear suppression of their ratios as
measured by HERMES in DIS experiments. Meanwhile, a moderate medium enhancement of the near-side correlation of two high-pT hadrons is found in central heavy-ion collisions, partially due to trigger bias caused by the competition between parton energy loss and the initial Cronin effect. 相似文献
132.
A. Majumder 《The European Physical Journal C - Particles and Fields》2005,43(1-4):259-262
Two particle correlations within a single jet produced in deeply inelastic scattering (DIS) off a large nucleus as well as in heavy-ion collisions are explored. These are performed within the framework of the medium modified dihadron fragmentation functions. The modification occurs due to gluon bremsstrahlung induced by multiple scattering. The modified fragmentation functions for dihadrons are found to follow closely that of single hadrons leading to a weak nuclear suppression of their ratios as measured by HERMES in DIS experiments. Meanwhile, a moderate medium enhancement of the near-side correlation of two high pT hadrons is found in central heavy-ion collisions, partially due to trigger bias caused by the competition between parton energy loss and the initial Cronin effect.Arrival of the final proofs: 21 March 2005PACS:
12.38.Mh, 11.10.Wx 相似文献
133.
Majumder U Rangnekar A Gothelf KV Reif JH LaBean TH 《Journal of the American Chemical Society》2011,133(11):3843-3845
DNA is a useful material for nanoscale construction. Due to highly specific Watson-Crick base pairing, the DNA sequences can be designed to form small tiles or origami. Adjacent helices in such nanostructures are connected via Holliday junction-like crossovers. DNA tiles can have sticky ends which can then be programmed to form large one-dimensional and two-dimensional periodic lattices. Recently, a three-dimensional DNA lattice has also been constructed. Here we report the design and construction of a novel DNA cross tile, called the double-decker tile. Its arms are symmetric and have four double helices each. Using its sticky ends, large two-dimensional square lattices have been constructed which are on the order of tens of micrometers. Furthermore, it is proposed that the sticky ends of the double-decker tile can be programmed to form a three-dimensional periodic lattice with large cavities that could be used as a scaffold for precise positioning of molecules in space. 相似文献
134.
Rhone TD Majumder D Dennis BS Hirjibehedin C Dujovne I Groshaus JG Gallais Y Jain JK Mandal SS Pinczuk A Pfeiffer L West K 《Physical review letters》2011,106(9):096803
Even though composite fermions in the fractional quantum Hall liquid are well established, it is not yet known up to what energies they remain intact. We probe the high-energy spectrum of the 1/3 liquid directly by resonant inelastic light scattering, and report the observation of a large number of new collective modes. Supported by our theoretical calculations, we associate these with transitions across two or more composite fermions levels. The formation of quasiparticle levels up to high energies is direct evidence for the robustness of topological order in the fractional quantum Hall effect. 相似文献
135.
Das S Badani PM Sharma P Vatsa RK Das D Majumder A Das AK 《Rapid communications in mass spectrometry : RCM》2011,25(8):1028-1036
Using time‐of‐flight mass spectrometry (TOFMS), laser‐induced photochemistry of ethyl bromide clusters has been investigated at three different wavelengths (viz. 266, 355 and 532 nm) utilizing nanosecond laser pulses of ~5 × 109 W/cm2. An interesting finding of the present work is the observation of multiply charged atomic ions of carbon and bromine at 355 and 532 nm, arising from the Coulomb explosion of (C2H5Br)n clusters. At 266 nm, however, the (C2H5Br)n clusters were found to exhibit the usual multiphoton dissociation/ionization behaviour. The TOFMS studies are complemented by measuring the total charge density of the ionized volume at 266, 355 and 532 nm, using the parallel plate method, and the charge densities were found to be ~2 × 109, 6 × 109 and 2 × 1011 charges/cm3, respectively. The significantly higher charge density and the presence of energetic, multiply charged atomic ions at 532 nm are explained by the higher ponderomotive energy of the 532 nm photon, coupled with the Coulomb stability of the residual multiply charged ethyl bromide clusters generated upon laser irradiation, due to their larger effective cluster size at 532 nm than at 355 and 266 nm. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
136.
Ghosh S Nayek P Roy SK Gangopadhyay R Rahaman Molla M Majumder TP 《The European physical journal. E, Soft matter》2011,34(4):35-6
A detailed comparative study of the dielectric and electro-optical properties of a ferroelectric liquid crystal (FLC) and
FLC after having doped with conducting polymer Poly (3,4-ethylenedioxythiophene) (PEDOT) nanotubes is done. The electro-optic
study reveals a lower electrical response time, rotational viscosity and spontaneous polarization in the FLC/PEDOT nanocomposite
system. By fitting the capacitance with voltage in a Preisach model, four dipolar species in both FLC and composites system
have been obtained. The orientation of the four dipolar species in the composites system is such that the effective dipole
moment in the transverse direction of the FLC molecule is less than that in FLC compound. 相似文献
137.
Amit Kumar Kundu Santanu Majumder Ashis Biswas Subhamoy Bhowmick Chandranath Pal Abhijit Mukherjee 《International journal of environmental analytical chemistry》2018,98(5):440-452
Regular monitoring of arsenic (As) in groundwater is crucial from public health perspectives as millions of people are suffering due to use of contaminated aquifer water for drinking purposes. The routine analyses, especially in developing nations, are mostly done in localised government/non-government laboratories with limited resources, having the target of analysing large number of samples in each run. Thus apart from analytical sensitivity, cost-effectiveness of the method and eco-friendliness of the experimental operation are key surreptitious factors. This demands optimisation of total As measurement methods and finding a method that gives ‘optimum benefit’ considering all these factors together. The present study therefore evaluates four common As (total) measurement methods [iodometric-colorimetric method, silver diethyl dithiocarbamate method, molybdenum blue method and hydride generation atomic absorption spectrophotometric (HG-AAS) method] practised in the Bengal Delta Plain, in view of their analytical sensitivity, related environmental hazard and experimental costs. It was found that the HG-AAS method is analytically more sensitive, whereas the iodometric-colorimetric method and the molybdenum blue method are better choices in terms of eco-friendliness and cost-effectiveness, respectively. However, when all three factors (analytical reliability, environmental hazard and cost) are considered simultaneously, the molybdenum blue method was found to be placed first in the ‘optimum performance rank’ list. It was also found that both environmental hazard and cost play a more crucial role than analytical reliability, although this is case specific and would differ from place to place around the globe. Finally based on the results, we have hypothesised a water testing strategy for developing countries such as India where the molybdenum blue method can be adapted as a screening method and later the HG-AAS method can be used to precisely identify the groundwater samples with As concentration below the WHO drinking water guideline value of 10 μg/L. 相似文献
138.
Observation of trapped light induced by Dwarf Dirac-cone in out-of-plane condition for photonic crystals 下载免费PDF全文
Existence of out-of-plane conical dispersion for a triangular photonic crystal lattice is reported. It is observed that conical dispersion is maintained for a number of out-of-plane wave vectors(k_z). We study a case where Dirac like linear dispersion exists but the photonic density of states is not vanishing, called Dwarf Dirac cone(DDC) which does not support localized modes. We demonstrate the trapping of such modes by introducing defects in the crystal. Interestingly, we find by k-point sampling as well as by tuning trapped frequency that such a conical dispersion has an inherent light confining property and it is governed by neither of the known wave confining mechanisms like total internal reflection, band gap guidance. Our study reveals that such a conical dispersion in a non-vanishing photonic density of states induces unexpected intense trapping of light compared with those at other points in the continuum. Such studies provoke fabrication of new devices with exciting properties and new functionalities. 相似文献
139.
Malabika Nayak Samit Majumder Pascale Lemoine Sasankasekhar Mohanta 《Journal of chemical crystallography》2008,38(12):937-942
Abstract The synthesis, characterization, and structure of a cyano-bridged two-dimensional supramolecule, [CuII(trans-chxn)2]3[CoIII(CN)6]2·2H2O (1; chxn = 1,2-diaminocyclohexane), have been described. The title compound crystallizes in the triclinic Pī space group with the unit cell parameters: a = 9.141(5) ?, b = 12.406(5) ?, c = 15.064(5) ?, α = 95.190(5)°, β = 94.460(5)°, γ = 109.510(5)°, V = 1593.0(12) ?3, and Z = 1. The compound contains two crystallographically different copper(II) and cobalt(III) centers. Each of the two copper(II)
ions is hexacoordinated by two diamines and two bridging cyanides. Two trans cyanides of one type of hexacyanometalate link one type of copper(II) center to result in one-dimensional chain, while two
pairs of trans cyanides of the second type of hexacyanometalate link both the types of copper(II) ions to result in the second dimension.
There are extensive hydrogen bonding interactions within the two-dimensional cyano-bridged sheet involving the solvated water
molecule, amine groups, and cyanide nitrogens.
Index Abstract Synthesis, characterization, and structure of a cyano-bridged two-dimensional CuIICoIII coordination polymer derived from trans-1,2-diaminocyclohexane as blocking ligand
Malabika Nayak, Samit Majumder, Pascale Lemoine, and Sasankasekhar Mohanta*
The synthesis, characterization, and structure of a cyano-bridged two-dimensional supramolecule, [CuII(trans-chxn)2]3[CoIII(CN)6]2 · 2H2O (chxn = 1,2-diaminocyclohexane), have been described.
相似文献
140.
Majumder U Cox JM Johnson HW Rainier JD 《Chemistry (Weinheim an der Bergstrasse, Germany)》2006,12(6):1736-1746
Gambierol, a representative of the marine ladder toxin family, consists of eight ether rings, 18 stereocenters, and two challenging pyranyl rings having methyl groups that are in a 1,3-diaxial orientation to one another. Herein we describe the generation of gambierol's A-C and F-H ring systems and demonstrate the versatility of the glycosyl anhydride, enol ether-olefin RCM strategy to fused polycyclic ethers. This work has both enabled us to generate sufficient quantities of the gambierol precursors and has enabled us to better understand the chemical transformations that were key to these efforts. Fundamental work included efforts to C-glycosides and C-ketosides, Claisen rearrangements, and enol ether-olefin RCM reactions. 相似文献