Synthesis of Cu–Cr diketo,sublimable, eutectic composite complex,rod crystals from LDH as suitable MOCVD precursor of CuCr2O4 catalysts upon ceramic preforms for N2O decomposition

Metal-acteylacetonates are important sublimable metal-organic precursors for metal-oxide thin film formation over solid preforms by MOCVD (Metal Organic Chemical Vapour Deposition) technique. Mixed-metal-acetylacetonates (MMAA) are suitable starting materials for mixed metal nano-oxidic thin film formation through such facile routes. Layered Double Hydroxides (LDH) of suitable metal ion combination can perform as appropriate starting base for neutralisation by enol form of 2,4-pentanedione or acteylacetonate tautomer ligands to obtain such MMAA. In this paper synthesis of composite crystals of Cu(II)/Cr(III) acetylacetonates (CCAA) is reported by the reaction of Cu–Cr-LDH with acetylacetone. The products were characterized by various different techniques. The surface area and pore volume analysis of the crystals showed the formation of nanopores in the compound. TEM analysis confirmed that the inner core of the nanoporous crystals of Cu(acac)₂ was covered by coating of poorly crystallised Cr(acac)₃ and they together form the composite crystals, and they together form the composite crystals. Due to eutectic mixture formation the melting point of CCAA lies in between the melting points of individual components Cu(acac)₂ and Cr(acac)₃ and shows sublimability, a property important for the formation of MOCVD films. The composite was used for CuCr₂O₄ spinel mixed oxide films formation over solid ceramic honeycomb monolithic substrates. Application prospects of the route in the field of catalysis is high as it can directly combine the benefits of mixed metal oxide catalysis and structured supports without the involvement of a third component. In this work the performance of such a catalytic device has been tested for low temperature decomposition of high Global Warming Potential (GWP) gas N₂O to N₂ and O₂.     

Optimization of alkaline protease production by Bacillus sp. using taguchi methodology

Optimization of alkaline protease production parameters by Bacillus sp. was investigated using Taguchi methodology. The pH of the medium was observed to be the most significant factor among all selected optimization parameters at an individual level. The combinatorial influence of least significant factors, inoculum level and salt solution concentration (at the individual level), resulted in an interacting severity index of 76%, suggesting their interactive role in the regulation of protease production in this microbial species. Protease production could be improved more than 100% with Taguchi’s optimized conditions of the medium composition by this microorganism.     

Preparation of 125I-Lanreotide and its biodistribution in murine model of melanoma

Lanreotide, a somatostatin analogue, was radioiodinated with ¹²⁵I to explore the possibility of using ¹²³I labeled lanreotide as a diagnostic radiopharmaceutical for tumors overexpressing somatostatin (SST) receptors. Radioiodination was carried out with ¹²⁵I using chloramine T as the oxidant. The labeling yield was >90%. Characterization of ¹²⁵I-Lanreotide was carried out by paper electrophoresis as well as HPLC. ¹²⁵I-Lanreotide was purified by chromatography using a C18 Sep-Pak column. Radiochemical purity of the purified ¹²⁵I-Lanreotide thus obtained was >99%. Significant tumor uptake of ¹²⁵I-Lanreotide was observed in C57BL/6 mice bearing melanoma.     

Mössbauer Study of La1−x Ca x Mn1−y 57Fe y O3 with x=0,0.25; y=0.01

Temperature dependent Mössbauer measurements are done on the samples of La_1–x Ca _x Mn_1–y ⁵⁷Fe _y O₃ with x=0 and 0.25, and y=0.01. With decreasing temperature, the specimen with x=0.25 shows a paramagnetic to ferromagnetic transition around 175 K. In the specimen x=0.0, the temperature dependence of both the center shift () and the recoilless fraction (f) can be fitted very well with the Debye theory with a _D=320±50 K. But for the specimens with x=0.25, f and show distinct deviations from the Debye behavior in the temperature range in which the resistivity shows a sharp decrease. Dips observed in both the f and around the transition temperature suggest that the Jahn–Teller distortion observed in these systems is dynamic in nature.     

Synthesis and studies on dichloro iodo triphenylphosphine oxide nickel(III)

A new compound of nickel(III), [Ni(OPPh₃)Cl₂I] has been prepared by the action of nitrosyl chloride or chlorine gas on [Ni(PPh₃)₂I₂]. Various physical studies of the compound are reported.     

Absorption spectra of Cu2+ in shattuckite and plancheite

Optical and EPR measurements are carried out on shattuckite, a copper bearing silicate. The EPR spectrum observed at 120 K reveales hyperfine structure for parallel and perpendicular components. The measured values are g6 = 2.402, g⊥ = 2.038, A6 = 112 × 10^-4 cm^-1 and A⊥ = 49.5 × 10^-4 cm^-1 and they indicate a tetragonal distortion for the Cu²⁺ion. Further, the constants P and K are evaluated and found to be 0.014 cm^-1 and 0.0112 respectively. The bands observed at 8160, 13330 and 16125 cm^-1 are assigned to the electronic states of Cu²⁺, in a crystal field subjected to tetragonal (C_4V) distortion. The crystal field parameters evaluated are Dq = -1333, Ds = -1565 and Dt = -380 cm^-1. Correlating the EPR and optical data, the orbital reduction factors are calculated as k6 = 0.89 and k⊥ = 0.59. It is confirmed from EPR and optical studies that the Cu²⁺ion in shattuckite is sited in an elongated octahedron. Similar studies are carried out for plancheite. The observed optical absorption spectrum of plancheite is attributed to Cu²⁺ sited in an elongated octahedron and tetragonal field parameters are evaluated.     

Switching surfaces inN-person differential games

Switching surfaces inN-person differential games are essentially similar to those encountered in optimal control and two-person, zero-sum differential games. The differences between the Nash noncooperative solution and the saddle-point solution are reflected in the dispersal surfaces. These are discussed through classification and construction procedures for switching surfaces. A simple example of a two-person, nonzero-sum game is considered. A complete solution of this game will be presented in a companion paper (Ref. 1).     

Radiative decays,photoproduction and total cross section of theψ particles

It is pointed out that the coupling characterizing theψ-γ vertex must change substantially between the limits,ψ on mass-shell which occurs inψ→e ⁺ e ⁻ and photon on mass-shell which is relevant in radiative decays likeψ→ππγ, ψ→ηγ and photoproduction ofψ. This has the consequence that the value ofψN total cross section must be larger than what is inferred from the use of naive vector dominance in photoproduction.