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31.
This work describes the synthesis of mixed oxide film of vanadium and ruthenium by pulsed deposition technique on multiwall carbon nanotubes and the decoration of gold nanoparticles on the mixed film. A ternary electrocatalyst has been developed for the electrochemical oxidation of hydrazine by combining two metal oxide mixtures with Au nanoparticles. Surface morphology and chemical composition of the electrode have been examined with SEM, EDX, HRTEM, EIS, and XRD. The peak current of hydrazine increased 9 times at the AuNPs/(VOx-RuOx)/CNT/GCE compared to the bare GCE, and the peak potential shifted to negative 848 mV. Linear sweep voltammetry (LSV) and amperometric techniques revealed that the AuNPs/(VOx-RuOx)/CNT/GCE displays linear concentration range 2.5–10000 µM (LSV) and the concentration range 0.03–100 µM (amperometry). The limit of detection (LOD) is 0.5 μM and 0.1 μM at (S/N = 3) for LSV and amperometric technique, respectively. The results obtained show a good RSD% of 2.1%–3.2% and reasonable recovery of 97%–108% of hydrazine detection. 相似文献
32.
Using the heavy quark approximation, we have studied the nonleptonic decay mode Λ
b
→Λ
c
a
1. We have included nonfactorizable contributions as well as factorizable ones in our analysis. The estimated branching ratio
for this process is (1.4±0.1)% and the asymmetry parameter α found to be −0.8. 相似文献
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Thirumurugan A Li W Cheetham AK 《Dalton transactions (Cambridge, England : 2003)》2012,41(14):4126-4134
Six inorganic-organic bismuth 2,6-pyridinedicarboxylate (pdc) compounds, [Bi(2,6-pdc)(3)]·3(dma), 1, [Bi(2,6-pdc)(3)]·3(dma)·2(H(2)O), 2, [Bi(2,6-pdc)(2)(dmf)]·(dma), 3, Bi(2,6-pdc)(2,6-pdcme)(MeOH), 4, [LiBi(2,6-pdc)(3)(H(2)O)]·2(dma), 5, and Li(5)Bi(2,6-pdc)(4)(H(2)O)(2), 6 (where dma = dimethyl ammonium cation, dmf = dimethylformamide and 2,6-pdcme = 6-methyl-oxycarbonyl pyridine 2-carboxylate) have been synthesized under solvothermal conditions and their structures determined by single crystal X-ray diffraction. Compounds 1-4 have molecular structures whereas compounds 5 and 6 form one- and three-dimensional frameworks, respectively. Compounds 1 and 2, both having similar monomeric bismuth coordination units, which are connected non-covalently into a (4,4)-connected square lattice by H-bonding interactions through dma cations. Compounds 3 and 4, both have a similar dimeric bismuth coordination unit. In 3, the dimers are connected into a one-dimensional chain by H-bonding interactions through dma cations. In the partially esterified and neutral 4, there was no such H-bonding interactions due to the absence of any dma cations. Compounds 5 and 6 have a similar monomeric bismuth coordination unit to that seen in 1 and 2. In 5, the monomers are connected through lithium cations into one-dimensional chains, which further interact non-covalently by H-bonding interactions through dma cations. In the lithium-rich 6, the monomers are connected by the lithium cations and 2,6-pdc anions into a three dimensional structure with intramolecular H-bonding interactions involving the water molecules. The non-porous 5 and 6 exhibit a reasonable amount of H(2) and CO(2) sorptions, respectively. Tb(3+)- and Eu(3+)-doped and co-doped 4 and 5 emit characteristic sensitized green/red/yellow-orange luminescence. 相似文献
35.
Recent observation and theoretical investigations have led to the significance of electrostatic ion cyclotron (EIC) waves
in the electrodynamics of acceleration process. The instability is one of the fundamental of a current carrying magnetized
plasma. The EIC instability has the lowest threshold current among the current driven instabilities. On the basis of local
analysis where inhomogeneities like the magnetic shear and the finite width current channel, have been ignored which is prevalent
in the magnetospheric environment. On the basis of non-local analysis interesting modification has been incorporated by the
inclusion of magnetic shear. In this paper we provide an analytical approach for the non-local treatment of current driven
electrostatic waves in presence of parallel electric field. The growth rate is significantly influenced by the field aligned
electron drift. The presence of electric field enhances the growth of EIC waves while magnetic shear stabilizes the system. 相似文献
36.
Single crystals of PbRe2O6 were obtained from a stoichiometric mixture of PbO and ReO3 at 500°C. The structure was determined by Patterson methods from X-ray four-circle diffractometer data using 2 270 (392 unique) reflections; RW(F) = 0.036. PbRe2O6 crystallizes in the trigonal space group R3m with a = 10.359(6) Å, c = 11.092(6) Å and Z = 9. The compound is isotypic with the trigonal modification of PbNb2O6 and contains an Re2O10 unit. Unlike other compounds containing this species, there is no metal-metal bonding. 相似文献
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