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The kinetic energy distribution of ground state muonic hydrogen atoms mu-p(1S) is determined from time-of-flight spectra measured at 4, 16, and 64 hPa H2 room-temperature gas. A 0.9 keV-component is discovered and attributed to radiationless deexcitation of long-lived mu-p(2S) atoms in collisions with H2 molecules. The analysis reveals a relative population of about 1%, and a pressure-dependent lifetime (e.g. (30.4 +21.4 -9.7) ns at 64 hPa) of the long-lived mu-p(2S) population, equivalent to a 2S-quench rate in mu-p(2S) + H2 collisions of (4.4 +2.1 -1.8) 10^11 s^-1 at liquid hydrogen density., Comment: 4 pages, 2 figures, accepted for publication in Physical Review Letters

Functional nanoparticles and polyelectrolytes were deposited over cotton fabrics using the electrostatic self-assembly (ESA) techniques. Silver, gold, platinum, palladium, nanoparticles as well as Individual nanolayers of poly(sodium 4-styrene sulfonate) (PSS) and poly(allylamine hydrochloride) (PAH) were deposited over cationized cotton woven fabrics. Textile fabrics offer unique challenges to the deposition of nanolayers because of their unique cross section as well as the chemical heterogeneity of their surface. Cationic cotton substrates were produced via epoxy functionalization of cellulose using 2,3- epoxypropyltrimethylammonium chloride. In order to validate the presence and composition of the self-assembled structure, X-ray photoelectron spectroscopy (XPS) and Transmission Electron Microscopy (TEM) were used. Quartz Crystal Microbalance was used to probe the degree of cationization of the cellulosic substrates as well. [ABSTRACT FROM AUTHOR]

In this the final year of the project the formation and evaluation of zwitterionic crosslinking of cellulosic fabric was accomplished. Wrinkle recovery performance was enhanced by sequential carboxymethylation and cationization of cotton fabric, indicating that ionic crosslinking between polymer chains had been achieved without added crosslinking material. Wet wrinkle recovery angles were greater than untreated fabric while tensile strength and elongation at break increased, in sharp contrast to conventional DMDHEU treatments that reduce these two fabric properties significantly. Work was begun on the use of covalently ionized cotton to develop exhaustible, durable flame retardant fabrics. [ABSTRACT FROM AUTHOR]

The deposition of functional polyelectrolytes over cotton fabrics using the electrostatic self-assembly (ESA) method is reported. Individual nanolayers of poly(sodium 4-styrene sulfonate) (PSS) and poly(allylamine hydrochloride) (PAH) were deposited over cationized cotton woven fabrics. Textile fabrics offer unique challenges to the deposition of nanolayers because of their unique cross section as well as the chemical heterogeneity of their surface. Cationic cotton substrates were produced via epoxy functionalization of cellulose using 2,3- epoxypropyltrimethylammonium chloride. X-ray photoelectron spectroscopy (XPS) and Transmission Electron Microscopy (TEM) were used to validate the presence of a selfassembled structure. TEM images indicated conformal and uniform coating of the cotton fibers and XPS spectroscopy data was in quantitative agreement with previous published data for the deposition of PSS and PAH over synthetic planar substrates. [ABSTRACT FROM AUTHOR]