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255complex so much increases the density of rovibronic levels that all resolution of AlO-based vibrational level structure is lost in excited-state complex formation.I0 ConclusionThe results obtained thus far indicate that using an extrapolation of the techniques we have outlined here, it will be possible to (1) evaluate nontransition-metal M(C0)2 (x = 1,2) binding energies, (2) study long-lived metal oxide-carbon dioxide solvation complexes formed in metal-C02 complex oxidation, and (3) characterize the spectroscopy of M-CO and M-C02 complexes. We believe that these metal atom based solvation complexes present an opportunity to study the middle ground region extending in various degrees from weak binding van der Waals interactions to strong chemical bonding.The spectra in Figure 3 suggest that C02 complex formation or solvation presents only a small perturbation to the electronic spectrum of the metal oxide. Not only do these results indicate that we are dealing with relatively weak binding of the C 0 2 to the product metal oxide producing a highly perturbed metal oxide excited electronic state, but also, in conjunction with recent results obtained when the transition metals are entrained in CO and subsequently oxidized with O3 or N02,6 these results indicate that the spectra of MCO , M(CO),, and M-C02 complexes might be observed through a variety of spectroscopies in the vicinity of known atomic transitions for the metal atoms of interest.Picosecond optical pumpprobe spectroscopy was used to measure electronic energy relaxation in aggregates of pseudoisocyanine on 40-A-diameter colloidal silica particles. The adsorption of pseudoisocyanine on colloidal silica wds accompanied by the appearance of a sharp band at 569 nm, called the J-band, in the absorption spectrum. The J-band arises from an optical transition to a single-exciton state of aggregates absorbed on colloids. Nonexponential signals obtained from transient optical bleaching of the J-band are discussed in terms of a polariton model.

A selectable logarithmic/linear response active pixel sensor cell with reduced fixed-pattern-noise is proposed. It is composed of four dynamic threshold metal-semiconductor-oxide field-effect transistors (DTMOSs), which have inherently fewer characteristic fluctuations than conventional bulk counterparts. Therefore this proposed active pixel sensor cell is expected to reduce fixed-pattern-noise as compared with that of a device composed of bulk metal-oxide-semiconductor field effect transistors (MOSFETs) without any external noise reduction circuitry particularly in the logarithmic response mode. The effectiveness of the proposed sensor cell is partly experimentally verified using test devices that simulate the readout portion of the proposed sensor cell.

A novel operation scheme that realizes a combined linear-logarithmic response in conventional photodiode-type (PD) threetransistor (3-Tr) active pixel sensor (APS) cells is presented. It has been revealed that, by setting a reset transistor in weak inversion through properly selected bias voltages, conventional PD 3-Tr APS cells can be operated with a seamlessly combined linear-logarithmic response. A modification in the conventional APS cells that enhances their dynamic ranges in a linear response mode is also described.

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