Parametric study of EAA polymer thin film deposition on carbon substrates in a fluidized electrode bed reactor

Electrodeposition of ethylene-co-acrylic acid (EAA) polymer, as thin films on carbon particle substrates, was carried out in a fluidized electrode bed reactor. Feeder current, time of deposition, and flow rate of anolyte (i.e., bed expansion or bed porosity) were the key parameters investigated. The film characteristics were evaluated through SEM and FTIR analyses and the amounts determined by weighing. The effect of these parameters on the electrodeposition process is discussed, and optimum conditions for deposition are proposed. Also, a possible mechanism for electrodeposition, particularly for the EAA–carbon system, is discussed.     

Low complexity ordered successive interference cancelation detection algorithm for uplink MIMO SC-FDMA system

In mobile communication, the most exploratory technology of fifth generation is massive multiple input multiple output (MIMO). The minimum mean square error and zero forcing based linear detectors are used in multiuser detection for MIMO single-carrier frequency division multiple access (SC-FDMA). When the received signal is detected and regularization sequence is joined in the equalization of spectral null amplification, these schemes experience an error performance and the signal detection assesses an inversion of a matrix computation that grows into complexity. Ordered successive interference cancelation (OSIC) detection is considered for MIMO SC-FDMA, which uses a posteriori information to eradicate these problems in a realistic environment. To cancel the interference, sorting is preferred based on signal-to-noise ratio and log-likelihood ratio. The distinctiveness of the methodology is to predict the symbol with the lowest error probability. The proposed work is compared with the existing methods, and simulation results prove that the defined algorithm outperforms conventional detection methods and accomplishes better performance with lower complication.     

Involution codes: with application to DNA coded languages

For an involution θ : Σ^* → Σ^* over a finite alphabet Σ we consider involution codes: θ-infix, θ-comma-free, θ-k -codes and θ-subword-k-codes. These codes arise from questions on DNA strand design. We investigate conditions under which both X and X⁺ are same type of involution codes. General methods for generating such involution codes are given. The information capacity of these codes show to be optimized in most cases. A specific set of these codes was chosen for experimental testing and the results of these experiments are presented.     

Electroinitiated polymerization coatings through packed and fluidized bed electrodes

Our previous studies on electroinitiated polymerization for formation of coatings on metal surfaces have all been in stationary cell systems. The feasibility of using either a packed bed or a fluidized bed cell in electroinitiated polymerization is now demonstrated, the objective being to form polymeric coatings on metallic and metal-coated nonmetallic particles. The metallic particles that have been used are aluminum and stainless steel and the monomer-electrolyte system used is DAA-sulfuric acid. A comparison of current densities under various cathode potentials for the packed and fluidized bed systems is presented. The coatings obtained are analyzed through IR to establish the polymer functional groups. Additionally, both elemental analyses and thermal neutron activation analyses have been carried out to establish the compositions of the polymer coatings.     

SMA polymer thin film electrodeposition on carbon particles

Electrodeposition of styrene-co-maleic anhydride (SMA) polymer, as thin films on carbon particle substrates, was carried out in a fluidized electrode bed reactor (FEBR). Feeder current, time of deposition, flow rate of anolyte (i.e., bed expansion or bed porosity), concentration of SMA in the anolyte, and pH of the anolyte were the key parameters investigated. The film characteristics were evaluated through SEM and FTIR analyses, the amounts determined by weighing. The effect of these parameters on the electrodeposition process is discussed and optimum conditions for deposition are proposed. Also, a possible mechanism for electrodeposition, particularly for the SMA–carbon system, is discussed. Furthermore, where relevant, the parameters and mechanism are compared with those for our parallel work on the ethylene-co-acrylic acid (EAA)–carbon system.     

Electroreduction of lauronitrile and stearonitrile

Higher aliphatic amines are extensively used as wetting agents, corrosion inhibitors and as anti-dusting agents. An electrochemical method for preparing laurylamine and stearylamine from their corresponding nitriles using nickel black cathode has been standardised in our laboratories. Both these nitriles underwent smooth reduction in ethanolic sulphuric acid medium to give a yield of around 80% amine for a current efficiency of 40–50%. Galvanostatic polarisation measurements indicated that the reduction is smooth only at lower current densities.     

Structural Phase Transitions and Thermoelectric Properties of AgPb<Subscript>18</Subscript>SbTe<Subscript>20</Subscript> Under Compression

The high-figure-of-merit thermoelectric material AgPb₁₈SbTe₂₀ has been investigated by in situ angular-dispersive x-ray diffraction (XRD) and x-ray absorption fine-structure (XAFS) measurements up to 30 GPa. Resistivity and thermopower were measured with Bridgman-type opposed metal anvil cells. The results show that the ambient cubic ( Fm[`3] m ) \left( {Fm\overline{3} m} \right) structure transforms to orthorhombic (Pnma) at 6.4 GPa and then to the CsCl-type ( Pm[`3] m ) \left( {Pm\overline{3} m} \right) structure at 15 GPa. The ambient cubic ( Fm[`3] m ) \left( {Fm\overline{3} m} \right) phase is found to be recoverable on releasing the pressure. The thermoelectric power is found to increase with pressure for the cubic phase. The XAFS studies performed at the Pb L ₃-edge and Ag K-edge along with resistivity studies complement the XRD findings.