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91.
A novel scheme for quantum communication having substantial applications in practical life is designed and analyzed. Specifically, we have proposed a hierarchical counterpart of the joint remote state preparation (JRSP) protocol, where two senders can jointly and remotely prepare a quantum state. One sender has the information regarding amplitude, while the other one has the phase information of a quantum state to be jointly prepared at the receiver’s port. However, there exists a hierarchy among the receivers, as far as powers to reconstruct the quantum state are concerned. A 5-qubit cluster state has been used here to perform the task. Further, it is established that the proposed scheme for hierarchical JRSP (HJRSP) is of enormous practical importance in critical situations involving defense and other sectors, where it is essential to ensure that an important decision/order that can severely affect a society or an organization is not taken by a single person, and once the order is issued, all the receivers do not possess an equal right to implement it. Further, the effect of different noise models (e.g., amplitude damping (AD), phase damping (PD), collective noise and Pauli noise models) on the HJRSP protocol proposed here is investigated. It is found that in AD and PD noise models a higher-power agent can reconstruct the quantum state to be remotely prepared with higher fidelity than that done by the lower-power agent(s). In contrast, the opposite may happen in the presence of collective noise models. We have also proposed a scheme for probabilistic HJRSP using a non-maximally entangled 5-qubit cluster state. 相似文献
92.
Anirban Chowdhury Akira KudoTakeshi Fujita Ming-Wei ChenTadafumi Adschiri 《The Journal of Supercritical Fluids》2011,58(1):136-141
Nano-TiO2 crystals showing visible light driven photocatalytic activity were synthesized by hydrothermal reaction in an ethanol-water mixture. The experiments were conducted to optimise the synthesis conditions for nano titania, in the range of temperature from 200 to 400 °C. X-ray diffraction depicted that the products obtained were anatase at 250 °C and above. For the products obtained at 250 °C, detailed analysis was conducted since it depicted high crystallinity with smallest particle sizes. Shape of the crystal was rounded rectangular with the size of 4 ± 1 nm to 7 ± 1 nm. The high-resolution transmission electron microscopy (HRTEM) revealed the existence of novel nano-twin structure in anatase grains and surface defects around the nanocrystals. Photocatalytic property was investigated for these undoped titania samples under UV and visible light. The nano twin structure, surface defects, and nano-meter size of the synthesized titania are believed to play a crucial role for the high catalytic activity. 相似文献
93.
The aim of this work is to investigate the effect of divalent cations on the structure and electrical properties of Ce0.85La0.1D0.05O2-δ (D = Ca, Sr and Ba) oxygen ion conductors. The X-Ray structural analysis confirms the presence of CeDO3 minor phase in addition to cubic fluorite phase of ceria in Sr2+ and Ba2+ added compositions. The lattice parameter of the compositions significantly depends on the ionic radius of dopants and the presence of D2+ ions in ceria lattice. The Ca2+ added composition shows the highest free oxygen vacancy concentration due to its lowest association energy and complete dissolution of Ca2+ ions into ceria lattice. The dopant-vacancy association energy and grain interior conductivity changes with the ionic radii of the divalent dopants. The grain boundary capacitance depends on dielectric constant, grain size and grain boundary thickness. The grain boundary conductivity shows 46% over total conductivity for Sr2+ added composition. The presence of CeDO3 phase and space charge layer promotes the grain boundary resistances and affects the ion dynamics. Schematic models are proposed to understand the ion migration in grain boundaries. The scavenging effect is found to be highest in Sr2+ ions added composition. The defect structures, the presence of CeDO3 phase and electrical properties are correlated with each other. 相似文献
94.
Dendrimers: Nano Molecular‐Platform: A Protocol to Write Energy Transmission Program Inside a Molecule for Bio‐Inspired Supramolecular Engineering (Adv. Funct. Mater. 10/2014)
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Subrata Ghosh Mrinal Dutta Satyajit Sahu Daisuke Fujita Anirban Bandyopadhyay 《Advanced functional materials》2014,24(10):1338-1338
95.
Anirban Guha Ronald M. Barron Ram Balachandar 《Journal of Materials Processing Technology》2011,211(4):610-618
In this paper, we have experimentally, numerically and theoretically investigated the water jet cleaning process. Very high speed water jets (∼80-200 m/s) are typically used in such cleaning operations. These jets diffuse in the surrounding atmosphere by the process of air entrainment and this contributes to the spreading of the jet and subsequent decay of pressure. Estimation of this pressure decay and subsequent placement of the cleaning object is of paramount importance in manufacturing and material processing industries. Also, the pressure distribution on the cleaning surface needs to be assessed in order to understand and optimize the material removal process. In an industrial setting, an experimental study is performed to formulate the pressure characteristics. It has been shown that the decay of stagnation pressure along the axial direction is linear. It also revealed that no cleaning is possible at radial locations greater than 1.68D from the centerline. Numerical simulations are performed to capture the process of air entrainment in the jet and the subsequent pressure characteristics. The simulation results are found to correctly predict the experimental data. Moreover, a theoretical model for evaluating the optimal and critical stand-off distances has also been derived. Our results indicate that the optimal stand-off distance in cleaning operations is ∼5D and the jet looses its cleaning ability at axial distances greater than ∼26D. 相似文献
96.
Recent literature on walking robots deals predominantly with multi-degrees-of-freedom leg mechanisms and machines capable of adopting several gaits.This paper explores the other end of the spectrum suggesting mechanisms derived from a four bar coupler curve for a one degree of freedom walking robot.Simulation of the walk indicates that body of the robot is able to move with low variation in velocity.The best strategy for changing the gait to enable the robot to walk over obstacles and the effect of change i... 相似文献
97.
The L-3-phenyl-2-(3-phenyl-ureido)-propionic acid (LH) and cadmium, manganese complexes of L, [ML2(H2O)2]n has syn–syn conformation around urea group whereas in a dinuclear sodium complex of L [NaL(H2O)3]2 the urea part adopts an anti–syn conformation. 相似文献
98.
Anirban Chakraborty James C. Earthman 《Metallurgical and Materials Transactions A》1998,29(3):957-964
Creep constrained grain boundary cavitation in a fully lamellar (FL) form of a titanium aluminide intermetallic alloy has
been studied using finite element (FE) techniques. Two different forms of FL models were considered. Cavitation was modeled
in the presence of grain boundary sliding (GBS) for the case of straight former γ grain boundaries. Models of cavitation without GBS were also performed for a FL microstructure with serrated former γ grain boundaries. The effect of cavitating facet interaction on rupture life has been studied. A comparison between the FL
forms and a dualphase equiaxed microstructure having the same phase ratio (α
2/γ) was also made to examine the relative susceptibility of these microstructures to high-temperature damage. It has been observed
that the overall effect of interaction between cavitating facets increases the rupture time significantly when these facets
are on adjacent grains. However, in the presence of GBS, cavitation on the facet with narrower separation effectively reduces
the cavity growth rate on the facet with wider separation.
This article is based on a presentation made in the symposium “Fundamentals of Gamma Titanium Aluminides,” presented at the
TMS Annual Meeting, February 10–12, 1997, Orlando, Florida, under the auspices of the ASM/MSD Flow & Fracture and Phase Transformations
Committees. 相似文献
99.
100.
The present paper outlines an experimental study to investigate the effects of cutting parameters on finish and power consumption
by employing Taguchi techniques. The high speed machining of AISI 1045 using coated carbide tools was investigated. A combined
technique using orthogonal array and analysis of variance was employed to investigate the contribution and effects of cutting
speed, feed rate and depth of cut on three surface roughness parameters and power consumption. The results showed a significant
effect of cutting speed on the surface roughness and power consumption, while the other parameters did not substantially affect
the responses. Thereafter, optimal cutting parameters were obtained. 相似文献