Effect of PVAc dispersal into PVA-NH4SCN polymer electrolyte

The present paper deals with ion transport studies on a new proton conducting composite polymer electrolyte — (PVA_x:NH₄SCN)_y:PVAc system. Complexation and morphology of the composite electrolyte films are discussed on the basis of X-ray diffraction and differential scanning calorimetry data. Coulometry and transient ionic current measurements revealed charge transport through protons. The maximum ion conductivity was found to be 7.4·10⁻⁴ S·cm⁻¹ for the composition: x=0.15, y=0.12. The observed conductivity behaviour is correlated to the morphology of the films. The temperature dependence of the electrical conductivity exhibits Arrhenius characteristics in two different temperature ranges separated by a plateau region related to morphological changes occurring in the electrolyte.     

On some generalized Sister Celine's polynomials

Certain generalizations of Sister Celine's polynomials are given which include most of the known polynomials as their special cases. Besides, generating functions and integral representations of these generalized polynomials are derived and a relation between generalized Laguerre polynomials and generalized Bateman's polynomials is established.     

Static and dynamic behavior of concrete and granite in tension with damage

A series of dynamic and static tensile-splitting experiments were performed on concrete and granite specimens to investigate the effect of induced damage on their tensile strength. These experiments were performed as part of a larger effort investigating the penetration process into the two materials. The strain rate each specimen was subjected to remained constant for these experiments, while the level of induced damage was increased. Damage was induced into the specimens through repeated drop-weight impacts and quantified using a statistical technique. The dynamic splitting experiments were performed using a split Hopkinson pressure bar (SHPB), while the static splitting experiments were conducted per the ASTM standard procedures D3967 and C496. As part of the investigation, photoelastic dynamic tensile-splitting experiments were also performed to establish the validity of using static relations for the determination of dynamic tensile strength. The experiments showed that the static splitting strength was highly dependent on the orientation of the induced damage with regard to the applied loading; however the dynamic tensile strength decreased with increasing damage with no apparent dependency on the random damage orientation. Photoelastic experiments have shown that the mechanism of failure changes for the dynamically tested damaged specimens, reducing their dependence on damage orientation.     

Temperature anisotropy induced magnetic drift wave instability

It is shown that magnetic drift waves are unstable in the presence of electron temperature anisotropy. Saturation by a quasilinear process which reduces the anisotropy is discussed.     

Thermodynamic perturbation theory for the (12-6-n) fluids

A perturbation method in which attractive forces are taken as perturbation of the repulsive (reference) forces is applied to calculate the thermodynamic properties of (12-6-n) fluids in terms of the properties of hard-sphere fluid. The numerical values of the thermodynamic properties (free energy per particle, compressibility and excess internal energy) for a range of temperature and density are given for (12-6-8) fluids. Further, two perturbation schemes are adopted to evaluate the total radial distribution function using the EXP version of the optimized cluster theory (OCT). The numerical results are reliable as reported at two states (T* = 1·036,ρ* = 0·65 andT* = 0·719ρ* = 0·85) for the (12-6-8) fluid and the Lennard-Jones (12-6) fluid as well.