Plasmon band gap generated by intense ion acoustic waves

In the presence of an intense ion acoustic wave, the energy-momentum dispersion relation of plasmons is strongly modified to exhibit a band gap structure. The intensity of an ion acoustic wave might be measured from the band gap width. The plasmon band gap can be used to block the nonlinear cascading channel of Langmuir wave decayComment: 3 pages, 3 figures, published on Po

Joining of thirty three percent by weight random carbon fibre reinforced low density polyethylene using variable frequency microwave

[Abstract]: This paper extends the range of applications for Variable Frequency Microwave facilities (VFMF) (2 – 18 GHz) to joining thirty three percent by weight carbon fibre reinforced low density polyethylene composite [LDPE/CF (33%)]. With a given power level, the composite was exposed to various exposure times to microwave irradiation. The primer or coupling agent used was 5-minute two-part adhesive containing 100% liquid epoxy and 8% amine, ie Araldite. Bond strengths of the joints were lap shear tested and results were compared with those obtained using fixed frequency (2.45 GHz) microwave processing. The VFMF was operated under software control, which provided automatic data logging facilities. The maximum lap shear strength of joint was 230 N/cm2 using variable frequency microwave facility while that obtained by fixed frequency microwave configuration was only 150 N/cm2. The former was found to be 53% stronger than the latter

Backward Raman compression of x-rays in metals and warm dense matters

Experimentally observed decay rate of the long wavelength Langmuir wave in metals and dense plasmas is orders of magnitude larger than the prediction of the prevalent Landau damping theory. The discrepancy is explored, and the existence of a regime where the forward Raman scattering is stable and the backward Raman scattering is unstable is examined. The amplification of an x-ray pulse in this regime, via the backward Raman compression, is computationally demonstrated, and the optimal pulse duration and intensity is estimated.Comment: 4 pages, 3 figures, submitted to PR

A method of solving sets of nonlinear algebraic equations Progress report

Methods for solving nonlinear algebraic equations in computer programs for nuclear magnetic resonance spectroscop

Spectral statistics along sequences of irreducible representations

We discuss the nearest neighbor distribution of the eigenvalues for hermitian generators in the Lie algebra of a semisimple complex Lie Group along a sequence of irreducible representations. After the basic definitions a limit theorem for rays of irreducible representation is formulated. Then it is proved that only a certain kind of rescaling will give meaning full results in the general case. Finally, we give explicit formulas for the Lipkin operator in the case of SU(3).Comment: 14 pages, 1 figur

Thermal analysis comparison between two random glass fibre reinforced thermoplastic matrix composites bonded by adhesives using microwaves: preliminary results

[Abstract]: This paper compares the thermal analysis of two types of random glass fibre reinforced thermoplastic matrix composites joined by adhesives using microwave energy. Fixed frequency, 2.45 GHz, microwave facility is used to join thirty three percent by weight random glass fibre reinforced polystyrene composite [PS/GF (33%)] and thirty three percent by weight random glass fibre reinforced low density polyethylene composite [LDPE/GF (33%)]. The facility used is shown in Figure 1. With a given power level, the composites were exposed to various exposure times to microwave irradiation. The primer or coupling agent used was 5-minute two-part adhesive. The heat distribution of the samples of the two types of composites was analysed and compared. The relationship between the heat distribution and the lap shear strength of the samples was also compared and discussed