Based on the quantum hydrodynamics theory, a proposed model for quantum dust acoustic waves (QDAWs) is presented including the dust size distribution (DSD) effect. A quantum version of Zakharov–Kuznetsov equation is derived adequate for describing QDAWs. Two different DSD functions are applied. The relevance of the wave velocity, amplitude, and width to the DSD is investigated numerically. The quantum effect changes only the soliton width. A brief conclusion is presented to the current findings and their relevance to astrophysics data is also discussed.

No abstract

The theory of the Raman sidesoattering instability in an inhomogeneous plasma is revisited. The growth rate is found from the eigesivalue of a second order ordinary differential equation in the Fourier domain. Under certain, rather easily satisfied constraints, the normalized growth rate depends on a single parameter involving laser str ongth, gradient scale length and resonant density. ABSTRACT SECURITY CLASSIFICATION

No abstract

In this study, polyvinyl alcohol (PVA) film was treated with low-cost microwave oven oxygen plasma. A number of several types of microscopies, including scanning electron microscopy, atomic force microscopy, X-ray photoelectron spectroscopy (XPS), contact angle and work of adhesion, were utilized in order to investigate the impact that the plasma had on the PVA film. After plasma treatment, it was discovered that the contact angle had decreased from 39° ± 0.4 to 20.8° ± 0.2, which suggests that the surface property had changed to a hydrophilic state due to increased hydroxyl groups (C=O, O=C–O) according to our finding from the results of XPS. The increase in surface roughness was observed. Recent research suggests that the properties of PVA can be modified by adjusting the degree of oxidation, which could lead to new improvements in applications based on PVA. This could pave the way for food packaging, air-conditioner panels, and coating applications.