Spin-polarized electronic density of states in amorphous iron

The spin-polarized electronicd-band density of states in amorphous iron are reported using recursion method. The magnetic moment of amorphous iron is found to be almost as high as BCC iron. This lends support to the view expressed by Kemény et al. that the extrapolation of experimental results obtained on samples containing less than 2% impurities to deduce the magnetic moment of pure amorphous iron may not be justified.     

Effect of a buffer layer, composition and annealing on the performance of a bulk heterojunction polythiophene/fullerene composite photovoltaic device

Post-annealing of P3HT/C₆₀-based plastic solar cells, composite ratio and, incorporation of a buffer layers at the ITO–polymer/fullerene composite interface and the polymer/fullerene composite–Al interface have shown significant improvement in the performance of the photovoltaic device, both in terms of open-circuit voltage and short-circuit current. The annealing temperature, time duration and P3HT/C₆₀ composite ratios have been optimized for the best performance of typical ITO/PEDOT:PSS/P3HT:C₆₀/LiF/Al solar cell. The C₆₀ content is very crucial because it improves the photocurrent in the beginning but after a certain value it leads to decrease in absorption, thereby decreasing the photocurrent.     

Numerical simulation of magnetic interactions in polycrystalline YFeO3

The magnetic behavior of polycrystalline yttrium orthoferrite was studied from the experimental and theoretical points of view. Magnetization measurements up to 170 kOe were carried out on a single-phase YFeO₃ sample synthesized from heterobimetallic alkoxides. The complex interplay between weak-ferromagnetic and antiferromagnetic interactions, observed in the experimental M(H) curves, was successfully simulated by locally minimizing the magnetic energy of two interacting Fe sublattices. The resulting values of exchange field (H_E=5590 kOe), anisotropy field (H_A=0.5 kOe) and Dzyaloshinsky–Moriya antisymmetric field (H_D=149 kOe) are in good agreement with previous reports on this system.     

Nearly scale invariant spectrum of gravitational radiation from global phase transitions

Using a large N sigma model approximation we explicitly calculate the power spectrum of gravitational waves arising from a global phase transition in the early Universe and we confirm that it is scale invariant, implying an observation of such a spectrum may not be a unique feature of inflation. Moreover, the predicted amplitude can be over 3 orders of magnitude larger than the naive dimensional estimate, implying that even a transition that occurs after inflation may dominate in cosmic microwave background polarization or other gravity wave signals.     

<Emphasis Type="Italic">Trans-</Emphasis>dichlorodioxobis(triphenylphosphate)molybdenum(VI), MoO<Subscript>2</Subscript>Cl<Subscript>2</Subscript>[OP(OPh)<Subscript>3</Subscript>]<Subscript>2</Subscript>

Abstract  The molecular structure of trans-dichlorodioxobis(triphenylphosphate) molybdenum(VI), MoO₂Cl₂[OP(OPh)₃]₂ has been determined. Crystal data: Monoclinic, Pn, a = 11.767(2), b = 10.341(2), c = 15.682(3) ?, β = 92.27(3)°, V = 1906.8(7) ?⁻³, Z = 2. Trans-dichlorodioxobis(triphenylphosphate)molybdenum(VI) was obtained by the reaction of molybdenum oxide, HCl and triphenylphosphate and was characterized by elemental analysis, IR, and ¹H-NMR spectroscopy. Index Abstract   Trans-dichlorodioxobis(triphenylphosphate)molybdenum(VI), MoO₂Cl₂[OP(OPh)₃]₂ V. Huch¹, R. Kumar², S. Mathur¹, R. Ratnani² The immediate environment around Mo is distorted octahedral with two cis-oxygen atoms and two trans-chlorine atoms along with two triphenylphosphate moieties.      

Enhanced luminance of MEH-PPV based PLEDs using single walled carbon nanotube composite as an electron transporting layer

An efficient electron transporting layer (ETL) based on single walled carbon nanotube (SWCNT) composites has been developed for poly [2-methoxy-5-(2′-ethyl-hexyloxy)-1,4-phenylene vinylene] (MEH-PPV) based orange polymer light emitting diodes (PLEDs) and its effect on the performance of PLEDs has been examined. It is observed that with increase in SWCNT concentration, in ETL, the luminance and luminous efficiency of the PLEDs increase (about 5 times increase in luminance is observed at 5% w/w SWCNT concentration). The SWCNTs present in the MEH-PPV ETL boost the mobility of electrons injected from the cathode towards the emissive layer by establishing highly conducting percolation paths. This balances the concentration of holes and electrons in the emissive layer, which leads to enhanced emission from the PLEDs.     

Increasing the luminous efficiency of an MEH-PPV based PLED using salmon DNA and single walled carbon nanotube

The combined effect of a salmon deoxyribonucleic acid (DNA)-based electron blocking layer and a single walled carbon nanotube (SWCNT) composite-based electron transport layer on the performance of a poly[2-methoxy-5-(2′-ethyl-hexyloxy)-1,4-phenylene vinylene] (MEH-PPV) polymer light emitting diode (PLED) has been examined. The SWCNT network in the composite layer improves electron injection from cathode and the DNA blocks these high mobility electrons at the electron blocking layer-polymer interface, leading to high luminance from the device. The luminous efficiency of the PLED is increased ∼20 times compared to that of a PLED using only MEH-PPV.     

SiO2@Fe2O3 core-shell nanoparticles for covalent immobilization and release of sparfloxacin drug

Silica-coated Fe(2)O(3) nanoparticles were synthesized as carriers for the covalent immobilization and release of antimicrobial drug sparfloxacin (SPFX). SPFX-loaded nanoparticles exhibited time-dependent drug release, with no measurable in vitro cytotoxicity, making the drug@nanoparticle conjugates potentially relevant for nanomedicine applications.     

A Sr(II)-Zr(IV)-Cd(II) Alkoxide Cluster: Synthesis and X-Ray Structure of [{Cd(OPri)3}Sr{Zr2(OPri)9}]2

New heterotrimetallic alkoxide [{Cd(OPrⁱ)₃}Sr{Zr₂(OPrⁱ)₉}]₂ (1) is obtained quantitatively in an anion-exchange reaction involving well-characterised iodide heterobimetallic alkoxide ICd{Zr₂(OPrⁱ)₉} and the alkali metal reagent KSr(OPrⁱ)₃. The formation of 1 is accompanied with an exchange of metals (Cd(II) and Sr(II)) between the constituting fragments (‘Cd{Zr₂(OPrⁱ)₉}⁺’ and ‘Sr(OPrⁱ)₃ ^?’) and the chelating Zr₂(OPrⁱ)₉ ^? anion, in 1, coordinates to Sr²⁺ in contrast to the precursor ICdZr₂(OPrⁱ)₉ where it is bound to Cd²⁺. The heterotrimetallic nature of 1 is unambiguously established by multinuclear (¹H, ¹³C and ¹¹³Cd) NMR spectral data and a single crystal X-ray diffraction analysis.     

Spectrophotometric Studies of V(V) Complexes of N-Methylaminothioformyl-N′-phenylhydroxylamine

The violet-colored complexes of V(V) and N-methylaminothio-formyl-N′-phenylhydroxylamine are extractable into chloroform. The spectrophotometric studies have shown that 1:3 and 1:4 (metal:ligand) complexes predominate in the acidity range 6.5–9 N and 9.5–10.5 N HCl, respectively. The values of stability constants, stepwise and overall, have been calculated by following extended Leden and Yatsimirskii methods. The analytical suitability of the reagent for the microdetermination of vanadium has also been investigated.