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The spatial confinement effect on the laser-induced plasma parameters and surface modifications of iron (Fe) has been investigated. The Fe plasma has been generated under ultrahigh vacuum (UHV) condition by employing Nd: YAG (532 nm, 6 ns) laser at different laser irradiances ranging from 3.3 to 10 GWcm $^{-2}$. Two important Fe plasma parameters, i.e., electron temperature ranging from 13 to 27 eV and electron number density ranging from $1.92\times 10^{15}$ cm $^{-3}$ to $4.60\times 10^{15}$ cm $^{-3}$ , are evaluated by employing Langmuir probe (LP) as diagnostic technique. The probe was placed at a distance of 1 cm from target. Both plasma parameters are found to be influenced by laser irradiances and spatial confinement. They increase with the increase in laser irradiances both in the presence and absence of metallic blockers. However, it is revealed that the values of both plasma parameters are slightly higher in the presence of blocker as compared to blocker-free case. The percentage increase in electron temperature varies from 10% to 15%, whereas percentage increase in electron density varies from 11% to 25%. These percentage increase in the values of Fe plasma parameters exceeds the limits of experimental errors (±2). Therefore, the role of spatial confinement via metallic blocker for the enhancement of plasma parameters is confirmed and is attributed to the reflection of shockwaves from the blocker. The surface modifications of laser irradiated Fe have been explored by scanning electron microscopy (SEM). Various features, such as ripples, ridges, and cones, have been observed on the surfaces of ablated Fe. More pronounced, organized, and fine structures are grown on the Fe surface in the presence of blocker at lower irradiances than the blocker-free case due to spatial confinement effect. The growth of ripples is attributed to Kelvin–Helmholtz instabilities. PACS: 61.80.Ba, 52.50. −b, 52.50.Jm, 52.50.Lp, 52.35.Tc, 35 52.38., 52.38.Dx. [ABSTRACT FROM AUTHOR]

In order to enhance the characteristic performance of cellulose acetate (CA) membranes, a novel nanofiller synergy is adopted herein for desalination purpose. Activated zinc oxide and aero-silica synergy in seven different ratio based combinations were introduced into CA matrix adopting solution mixing technique. The functionalized nanofillers loading impact on membranes surface texture, crystalline structural difference, functional groups presence, thermal decomposition and phase transition temperatures were scrutinized. The sole membranes were practically employed to determine salts (NaCl and MgCl2) rejection tested by dead-end filtration system. Time dependent flux rate and fouling study were performed to decide the reuseability of nanocomposite membranes. The results validate a remarkable improvement by idiosyncratically synthesized nanocomposite membranes. [ABSTRACT FROM AUTHOR]