Rate processes in proteins are often not adequately described by simple exponential kinetics. Instead of modeling the kinetics in the time domain, it can be advantageous to perform a numerical inversion leading to a rate distribution function f(lambda). The features observed in f(lambda) (number, positions, and shapes of peaks) can then be interpreted. We discuss different numerical techniques ...

the acetone sensitized photolysis of the title compound gave 2-(2- oxopropy1)-9,9- dimethyl bicyclo [3.3.l]nona-3-one. a bridgehead cyclopropane intermediate was then suggested for the formation of the photoproduct

Motivated by Yung and Miller's [199• suggestion that N20 is isotopically fractionated during UV photolysis in the stratosphere, we have studied the photolysis rates of the •4N•SN•60 and •SN•4N•60 structural isotopomers. In this study, we follow the concentrations of these compounds with FTIR spectroscopy during photolysis at 213 nm. When fitted to a Rayleigh fractionation model, the observation...

The photolysis of chlorine peroxide (ClOOCl) is a key chemical step in the depletion of polar stratospheric ozone. As such, precise measurements of the absorption cross sections for ClOOCl are required. In this paper we provide two critical pieces of laboratory data with which to constrain the rate of ozone depletion. First, we provide an optically pure ClOOCl spectrum in the photolytically imp...

Chemical signals generated at synapses are highly limited in both spatial range and time course, so that experiments studying such signals must measure and manipulate them in both these dimensions. We describe an optical system that combines confocal laser scanning microscopy, to measure such signals, with focal photolysis of caged compounds. This system can elevate neurotransmitter and second ...

This study presents the first modeling estimates of the potential effect of gasand particle-phase organic photolysis reactions on the formation and lifetime of secondary organic aerosols (SOAs). Typically only photolysis of smaller organic molecules (e.g., formaldehyde) for which explicit data exist is included in chemistry–climate models. Here, we specifically examine the photolysis of larger ...

Peroxyacetyl nitrate (PAN) vapor was photolyzedat 248 nmandthe N03 photoproduct wasdetected bylaser induced fluorescence. Thequantum yield fortheproduction of N03 was determined by comparison to N 205 photolysis data taken under identical experimental conditions. Contributions to the observed laser induced fluorescence were found to arise from excited state photoproducts such as N02* . The exci...

The UV-visible absorption spectrum of gaseous IONO 2 has been measured over the wavelength range 245–415 nm using the technique of laser photolysis with time-resolved UV-visible absorption spectroscopy. IONO 2 was produced in situ in the gas phase by laser flash photolysis of NO 2 /CF 3 I/N 2 mixtures. Post-flash spectra were deconvolved 5 to remove contributions to the observed absorption from...

The study of mitochondria and mitochondrial Ca2+ signalling in localised regions is hampered by the lack of tools that can uncouple the mitochondrial membrane potential (DeltaPsi(m)) in a spatially predefined manner. Although there are a number of existing mitochondrial uncouplers, these compounds are necessarily membrane permeant and therefore exert their actions in a spatially unselective man...