Ultrasonic-assisted activated biomass (fishtail palm Caryota urens seeds) for the sequestration of copper ions from wastewater

Research on Chemical Intermediates - Caryota urens seeds are an agro-based material that can be used as an eco-friendly and low cost adsorbent for the removal of metal ions. In the present study,...     

Designing copper–zirconium based nanowires for improving yield strength and plasticity by configuring surface atoms

Epitaxial-Bain-Path and Uniaxial-Bain-Path studies reveal that a B2-CuZr nanowire with Zr atoms on the surface is energetically more stable compared to a B2-CuZr nanowire with Cu atoms on the surface. Nanowires of cross-sectional dimensions in the range of ~20–50 Å are considered. Such stability is also correlated with the initial state of stress in the nanowires. It is also demonstrated here that a more stable structure, i.e., B2-CuZr nanowire with Zr atoms at surface shows improved yield strength compared to B2-CuZr nanowire with Cu atoms at surface site, over range of temperature under both the tensile and the compressive loadings. Nearly 18% increase in the average yield strength under tensile loading and nearly 26% increase in the averaged yield strength under compressive loading are observed for nanowires with various cross-sectional dimensions and temperatures. It is also observed that the B2-CuZr nanowire with Cu atom at the surface site shows a decrease in failure/plastic strain with an increase in temperature. On the other hand, B2-CuZr nanowires with Zr at the surface site shows an improvement in failure/plastic strain, specially at higher temperature as compared to the B2-CuZr nanowires which are having Cu atoms at the surface site. Finally, a possible design methodology for an energetically stable nano-structure with improved thermo-mechanical properties via manipulating the surface atom configuration is proposed.     

Some invariant solutions for non-conformal perfect fluid plates in 5-flat form in general relativity

A set of six invariant solutions for non-conformal perfect fluid plates in 5-flat form is obtained using one-parametric Lie group of transformations. Out of the six solutions so obtained, three are in implicit form while the remaining three could be expressed explicitly. Each solution describes an accelerating fluid distribution and is new as far as authors are aware.     

κ-Minkowski spacetime and the star product realizations

We investigate a Lie algebra-type κ-deformed Minkowski spacetime with undeformed Lorentz algebra and mutually commutative vector-like Dirac derivatives. There are infinitely many realizations of κ-Minkowski space. The coproduct and the star product corresponding to each of them are found. An explicit connection between realizations and orderings is established and the relation between the coproduct and the star product, provided through an exponential map, is proved. Utilizing the properties of the natural realization, we construct a scalar field theory on κ-deformed Minkowski space and show that it is equivalent to the scalar, nonlocal, relativistically invariant field theory on the ordinary Minkowski space. This result is universal and does not depend on the realizations, i.e. the orderings, used.     

基于非线性材料二次谐波与混频特性非逻辑门运算的全光实现(英文)

Optics has already been proved as a successful candidate for conducting parallel logic, arithmetic and algebraic operations. Several all-optical data processors were proposed since last few decades. To implement these systems, different data encoding decoding techniques such as polarization encoding, tristate, quartenary state, multivalued state, symbolic substitution technique etc. have already been proposed. All these are done to use optics in a suitable platform. We propose here a new concept of encoding data by adopting frequencies variation technique for conducting a inversion operation successfully.     

Performance analysis of an integrated scheme in optical burst switching high-speed networks

A new integrated scheme based on resource-reservation and adaptive network flow routing to alleviate contention in optical burst switching networks is proposed. The objective of the proposed scheme is to reduce the overall burst loss in the network and at the same time to avoid the packet out-of-sequence arrival problem. Simulations are carried out to assess the feasibility of the proposed scheme. Its performance is compared with that of contention resolution schemes based on conventional routing. Through extensive simulations, it is shown that the proposed scheme not only provides significantly better burst loss performance than the basic equal proportion and hop-length based traffic routing algorithms, but also is void of any packet re-orderings.     

Terahertz optical asymmetric demultiplexer based tree-net architecture for all-optical conversion scheme from binary to its other 2n radix based form

To exploit the parallelism of optics in data processing,a suitable number system and an efficient encoding/decoding scheme for handling the data are very essential.In the field of optical computing and parallel information processing,several number systems like binary,quaternary,octal,hexadecimal,etc.have been used for different arithmetic and algebraic operations.Here,we have proposed an all-optical conversion scheme from its binary to its other 2n radix based form with the help of terahertz optical asymmetric demultiplexer (TOAD) based tree-net architecture.     

Liquid polyamorphism: Possible relation to the anomalous behaviour of water

We present evidence from experiments and computer simulations supporting the hypothesis that water displays polyamorphism, i.e., water separates into two distinct liquid phases. This concept of a new liquid-liquid phase transition is finding application to other liquids as well as water, such as silicon and silica. Specifically, we investigate, the relation between changes in dynamic and thermodynamic anomalies arising from the presence of the liquid-liquid critical point in (i) Two models of water, TIP5P and ST2, which display a first order liquid-liquid phase transition at low temperatures; (ii) the Jagla model, a spherically symmetric two-scale potential known to possess a liquid-liquid critical point, in which the competition between two liquid structures is generated by repulsive and attractive ramp interactions; and (iii) A Hamiltonian model of water where the idea of two length/energy scales is built in. This model also displays a first order liquid-liquid phase transition at low temperatures besides the first order liquid-gas phase transition at high temperatures. We find a correlation between the dynamic fragility crossover and the locus of specific heat maxima C_P^max (“Widom line”) emanating from the critical point. Our findings are consistent with a possible relation between the previously hypothesised liquid-liquid phase transition and the transition in the dynamics recently observed in neutron scattering experiments on confined water. More generally, we argue that this connection between C_P^max and the dynamic crossover is not limited to the case of water, a hydrogen bonded network liquid, but is a more general feature of crossing the Widom line, an extension of the first-order coexistence line in the supercritical region. Dedicated to Armin Bunde on the occasion of his 60th birthday.