Photoreduction of CHCl in Aqueous SPEEK/HCO Solutions Involving Free Radicals.

Exposure of sulfonated poly(ether etherketone), SPEEK, in aqueous solutions to 350 nm photons induced reduction of CHCl to CHCl and chloride ions in the presence of HCOH/HCO buffers or poly(vinyl alcohol), PVA. The kinetics of the SPEEK-sensitized photoreaction was characterized by quantum yields of halide ion formation, ϕ(Cl), evaluated from in situ determinations of [Cl]. Particularly efficient reductions took place when formate buffers served as H atom donors in the absence of air and with excess CHCl.

Radical Chain Reduction of CCl Initiated by Illumination of SPEEK Solutions.

Efficient reduction of CCl took place upon exposure to 350-nm photons of aqueous solutions containing sulfonated poly(ether etherketone) (SPEEK) as a sensitizer and either poly(vinyl alcohol) (PVA) or HCOH/HCO buffer. The photoreaction formed chloride ions whose concentration increased linearly with time in solutions free of O, whereas slower reductions occurred in the presence of air. Utilization of formate buffer as the H-atom donor yielded photoreactions at least 10 times faster than those in the presence of PVA and generated CHCl as another reaction product.

Photogeneration of H2O2 in Water-Swollen SPEEK/PVA Polymer Films.

Efficient reduction of O2 took place via illumination with 350 nm photons of cross-linked films containing a blend of sulfonated poly(ether etherketone) and poly(vinyl alcohol) in contact with air-saturated aqueous solutions. Swelling of the solid macromolecular matrices in H2O enabled O2 diffusion into the films and also continuous extraction of the photogenerated H2O2, which was the basis for a method that allowed quantification of the product. Peroxide formed with similar efficiencies in films containing sulfonated polyketones prepared from different precursors and the initial photochemical process was found to be the rate-determining step.

Photogeneration of H2O2 in SPEEK/PVA aqueous polymer solutions.

Photolysis of air-saturated aqueous solutions containing sulphonated poly(ether etherketone) and poly(vinyl alcohol) results in the generation of hydrogen peroxide. Consumption of oxygen and H2O2 formation are initially concurrent processes with a quantum yield of peroxide generation of 0.02 in stirred or unstirred solutions within the range of 7 ≤ pH ≤ 9.

Sulfonated poly(ether ether ketone)/poly(vinyl alcohol) sensitizing system for solution photogeneration of small Ag, Au, and Cu crystallites.

Illumination of air-free aqueous solutions containing sulfonated poly(ether ether ketone) and poly(vinyl alcohol) with 350 nm light results in benzophenone ketyl radicals of the polyketone. The polymer radicals form with a quantum yield 0.02 and decay with a second-order rate constant 6 orders of magnitude lower than that of typical alpha-hydroxy radicals.

Polymer-initiated photogeneration of silver nanoparticles in SPEEK/PVA films: direct metal photopatterning.

Cross-linking of sulfonated poly(ether-ether)ketone-poly(vinyl alcohol) (SPEEK-PVA) materials yields flexible polymer films, possessing high light-sensitivity and ion-exchange capabilities. Adsorbed Ag+ ions are photoreduced in the film under illumination (lambda = 350 nm), leading to metal nanoparticle formation in places where the film has been exposed to the light. Nanoparticles form via reduction of Ag+ by the polymeric alcohol radicals, generated in the system as a result of photochemical H-abstraction from PVA molecules by the excited carbonyl triplet state of SPEEK.

Attitudes toward people with disabilities and judgments of employment potential.

The relationship between employers' expressed attitudes toward people with disabilities and their impressions of the employment potential of female job applicants was investigated. 120 subjects viewed videotapes of a simulated interview situation which included either an able-bodied applicant, one on crutches, or one in a wheelchair. The dependent measures included a scale for employment characteristics and management potential and the Attitudes Toward Disabled Persons Scale.

Metabolic effects of liquid protein.

In the first experiment, the liquid protein product (LP) tested would not support growth in rats when fed at the 8% protein level in an otherwise nutritionally adequate diet. The product was composed of an imbalanced mixture of amino acids which could not be used optimally for protein synthesis and which resulted in appetite depression. Total plasma nonessential amino acids increased significantly in the rats receiving LP, while total plasma essential amino acids were not significantly different.