Separation of NCA 88Zr from proton irradiated natY target: a novel approach using low cost bio-sorbent potato peel charcoal

Separation of no-carrier-added (NCA) ⁸⁸Zr from natural yttrium target irradiated with proton beam has been studied using nature-resourced material, potato peel, which is a commonly available domestic waste. Here, an attempt has been undertaken to exploit natural resource as separating agent. Good separation of NCA ⁸⁸Zr from bulk Yttrium target could be achieved at 0.01 M HCl concentration, when extraction was carried out using 20 mg potato peel charcoal—a natural bio-sorbent. ⁸⁸Zr was extracted in the solid phase leaving behind bulk Y in the aqueous phase.

     

Recent developments in multiphysics computational models of physiological flows

A mini-symposium on computational modeling of fluid–structure interactions and other multiphysics in physiological flows was held at the 11th World Congress on Computational Mechanics in July 2014 in Barcelona, Spain. This special issue of Theoretical and Computational Fluid Dynamics contains papers from among the participants of the mini-symposium. The present paper provides an overview of the mini-symposium and the special issue.     

Similarity solution and lie symmetry for a coupled nonlinear system

The Lie point symmetries of a set of coupled nonlinear partial differential equations are considered. The system is an extended version of the usual nonlinear Schrödinger equation. In the similarity variable deduced from the symmetry analysis, the system is equivalent to the Painlevé III in Ince's classification. By starting from a solution of the Painlevé equation, one can reproduce various classes of solutions of the original PDEs. Such solutions include both rational and progressive types or a combination of the two.     

Electronic structure of the calcium monohydroxide radical

Effective valence shell Hamiltonian H(v) calculations are used to map out three-dimensional potential energy surfaces for the 12 lowest electronic states of the CaOH radical. Excitation energies and spectroscopic constants are compared with experiment and prior computations where available, but many previously unavailable data are provided, including excited state dipole moments and oscillator strengths. Particular attention is paid to clarify the nature of nonlinear and quasilinear excited states, Renner-Teller couplings, and state mixings. The F (2)Pi and G (2)Pi (6 (2)A(') and 8 (2)A(')) states are both found to possess nonlinear local minima, due to an avoided crossing. Attention is also focused on the characteristics of basis sets necessary in high-accuracy calculations for the CaOH radical.     

Versatility of 2,6-diacetylpyridine (dap) hydrazones in stabilizing uncommon coordination geometries of Mn(II): synthesis, spectroscopic, magnetic and structural characterization

Five seven- or eight-coordinate manganese complexes of hydrazone ligands have been prepared. Three seven-coordinate neutral Mn(II) complexes: [Mn(dapA2)]n (1), [Mn(dapB2)(H2O)2] (2), [Mn(dapS2)(H2O)2] (3) have been synthesized from the bis-Schiff bases of 2,6-diacetylpyridine: dap(AH)2, dap(BH)2 and dap(SH)2 (AH = anthraniloyl hydrazide, BH = benzoyl hydrazide, SH = salicyloyl hydrazide), respectively. Two eight-coordinate Mn(II) complexes: [Mn(dapS)2] (4) and [Mn(dapB)2].3H2O (5) have been synthesized from the mono-Schiff bases dapBH and dapSH, respectively. The complexes have been characterized by elemental analyses and by IR, UV-Vis., FAB mass, EI mass and EPR spectroscopy. The molecular structures of 1, 3.DMF and 4.DMF have been determined by single-crystal X-ray diffraction. The mono-Schiff bases are monoanionic and the bis-Schiff bases are dianionic. The octa-coordinated mono-Schiff base complex 4 adopts a dodecahedral geometry, while the hepta-coordinated bis-Schiff base complex 1 forms a one-dimensional linear polymeric chain. A weak antiferromagnetic exchange interaction (J=-0.15 cm(-1)) between the Mn(II) ions in is attributed to weak Mn...Mn interaction through the PhNH(2) moiety of the ligand, as indicated by extended-Hückel molecular orbital calculations. A good simulation of the EPR spectrum of a frozen solution (DMSO at 4 K) of compound 1 was obtained with g=2.0, D=0.1 cm(-1), E=0.01 cm(-1). The EPR spectrum of a powdered sample of compound 1 shows a large broadening of the signal, due in part, to the important zero-field splitting of the hepta-coordinated Mn(II) ion.     

Computing the number of ways of representing primes by a norm form

Formulae for the number of different integral solutions ofa ²+b²+c²+d²+ac+bd=p are given wherep is a prime and the solution satisfies certain natural congruence conditions. Similar formulae are given for the case of the quadratic forma ²+b²+2c²+2d²+ac+bd.     

Binariness and rational choice

The concept of numerical representability of preferences together with maximality is at the heart of the concept of rationality embodied in classical optimization models. The difficulty of representing social preferences arises from inherent intransitivities thrown up by democratic voting procedures and by non-binary choice rules which need to be adopted to cope with these intransitivities. An alternative (weaker) concept of representability is developed and it is shown that this concept can partially accommodate intransitivity and non-binariness. ‘Weak transitivity’ and ‘weak binaries’ conditions are provided and it is shown that these conditions are necessary and sufficient for ‘weak representability’. While the weak transitivity condition would be violated by social aggregation procedures, the non-binary functions used by social choice theorists do indeed satisfy the condition of ‘weak binariness’.     

Synthesis and Crystal Structure of a Complex of Palladium(II) with 2-Hydroxyimino-3-(2-hydrazonopyridyl)-butane

Abstract  

Schiff-base condensation of an equimolar proportion of diacetyl-monoxime and 2-hydrazino pyridine in methanol gives rise to 2-hydroxyimino-3-(2-hydrazonopyridyl)-butane (HL). The ligand has been characterised by FT-IR, ¹H NMR and UV–Vis spectra. Reaction of 1:1 stoichiometric proportion of HL with Na₂[PdCl₄] in methanol affords a mononuclear palladium(II) compound, [PdLCl]·H₂O (1). The compound is characterised by C, H and N analyses, FT-IR, conductivity measurement, UV–Vis spectra, thermal analysis and magnetic susceptibility measurement. The X-ray crystal structure of the title compound (1) has been determined. The compound crystalises in the triclinic space group P[`1] Poverline{1} with a = 7.3033(3), b = 9.4139(4), c = 9.4445(5) ?, α = 79.789(3), β = 68.285(2), γ = 77.978(3)o, V = 586.42(5) ?³ and Z = 2. Pd(II) is in ‘N₃Cl’ coordination chromophore. The geometry around Pd(II) is square-planar. The compound is essentially diamagnetic.     

Large capacity optical router based on arrayed waveguide gratings and optical loop buffer

This paper presents optical packet switch architecture with large buffering capacity for the contention resolution of the packets. The main feature of the architecture is no requirement of Demux/Mux and splitter/combiner which are used in most of the other loop buffer based switch architectures. Therefore physical loss of the architecture is very less, and switch performance is not limited by the physical degradation of the signal. In the buffer, TWCs/SOAs are replaced by Tunable Fiber Bragg Gratings (TFBGs). The use of TFBGs inside the buffer is a novel approach towards buffering structure. The architecture presented here can be modeled as output queue buffer scheme. This paper investigates the advantages of the proposed architecture over the earlier architecture. The performance of the architecture in terms of physical layer parameters (loss analysis, power analysis and noise analysis), packaging volume and optical cost is done.