New polymer electrolyte for electrochemical application

A solid polymer electrolyte consisting of poly vinylpyrrolidone (PVP) and potassium iodide (KI) were developed, characterized for possible application in dye sensitized solar cell (DSSC) as an electrolyte. Complex impedance spectroscopy revealed the enhancement in electrical conductivity (σ) by salt doping and a conductivity maximum was obtained at 30 wt% KI concentration. Dielectric phenomena also support the σ data. Fourier transform infrared spectroscopy (FTIR) confirmed the composite nature of polymer electrolyte film. Using maximum electrical conductivity film we have fabricated a DSSC which shows 0.14% efficiency at 1 sun condition.     

Compositional and configurational sequence determination of methacrylonitrile–vinylidene chloride copolymers by nuclear magnetic resonance spectroscopy

Methacrylonitrile–vinylidene chloride (M/V) copolymers of different composition were prepared by bulk polymerization using benzoyl peroxide as an initiator under nitrogen atmosphere in a sealed tube. The copolymer composition was determined from quantitative ¹³C[¹H] NMR spectra. The reactivity ratios for M/V copolymers obtained from a linear Kelen–Tudos method and nonlinear error‐in‐variables method are r_M = 2.47 ± 0.14, r_V = 0.40 ± 0.02, and r_M = 2.43, r_V = 0.39, respectively. The complete spectral assignment in term of compositional and conformational sequences of these copolymers were done with the help of distortionless enhancement by polarization transfer, two‐dimensional heteronuclear single‐quantum coherence spectroscopy. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 96: 1865–1874, 2005     

Amphiphilic chitosan/acrylic acid/thiourea based semi-interpenetrating hydrogel: Solvothermal synthesis and evaluation for controlled release of organophosphate pesticide,triazophos

The current study reports the solvothermal synthesis of amphiphilic chitosan-based semi-interpenetrating (CAT-SIPH) hydrogel for controlled release of an organophosphate pesticide, triazophos. CAT-SIPH is prepared from natural backbone polymer chitosan (CS) and monomer, acrylic acid (AA) employing initiator (K₂S₂O₈), and cross-linker, thiourea (CSN₂H₄) using solvothermal technique under 7 Psi pressure in an autoclave. The polymerization reaction variables like reaction time, the volume of solvent, concentration of initiator, cross-linker, and monomer are optimized to get the best product yield in terms of percentage grafting. The optimized conditions for solvothermal polymerization reaction carried out for 60 min are solvent volume (10 ml), concentrations of acrylic acid (0.2 mol/L), K₂S₂O₈ (0.45 × 10⁻²mol/L) and thiourea (1.75 × 10⁻⁴ mol/L). The swelling behavior of CAT-SIPH hydrogel synthesized under optimized conditions is studied in the terms of swelling ratio. CAT-SIPH is characterized by Fourier transform infrared spectra (FT-IR), ^IHNMR, thermal analysis (TA), Zeta potential, and scanning electron microscopy (SEM). The potential of cross-linked hydrogel CAT-SIPH for controlled release of an organophosphate pesticide, Triazophos on to sandy loam soil is assessed. The experimental investigations proved that synthesized hydrogel can be effectively employed as a pesticide carrier for controlled release on to loamy soil as the maximum release (53%) is observed even after 25 days at pH 6 and value get lowered under acidic and basic conditions. The present investigation demonstrated the potential of chitosan-based CAT-SIPH hydrogel as a pH-responsive release vehicle for agrochemicals onto the soil matrix and offers a potential solution for the prevention of surface and groundwater contamination.     

An unsupervised defect detection model for a dry carbon fiber textile

Journal of Intelligent Manufacturing - Inspection of dry carbon textiles is a key step to ensure quality in aerospace manufacturing. Due to the rarity and variety of defects, collecting a...     

Reflection and transmission between an orthotropic thermoelastic half-space and an initially stressed orthotropic rotating thermoelastic diffusive half-space

Abstract

The purpose of present investigation is to study the reflection and transmission phenomena at the plane interface between an orthotropic thermoelastic half-space and an initially stressed orthotropic thermoelastic rotating half-space with diffusion. The enuciation is applied to generalized thermoelasticity based on Lord-Shulman theory. The amplitude and energy ratios of the reflected and transmitted waves are derived and the numerical computations have been carried out with the help of MATLAB programing. The effects of initial stress, rotation and diffusion parameters on the amplitude ratios are depicted graphically. It has been verified that at each angle of incidence, there is no dissipation of energy at the interface during reflection and transmission phenomena. Moreover, the effect of anisotropy is also depicted on the velocities of various reflected and transmitted waves. The velocities of these waves are found to depend on the angle of propagation in an orthotropic medium. This dependence of velocities on the direction of propagation is shown graphically.