A comparison of the dissolution of model compounds and the kerogen of Green River oil shale by oxidation with perchloric acid — A model for the kerogen of Green River oil shale

A stepwise degradation of a kerogen concentrate of Green River oil shale was effected by oxidation with perchloric acid of varying boiling point and concentration. Dissolution of the kerogen concentrate occurred between 160 and 170°C. Several model compounds were also oxidized with perchloric acid. The model compounds were polyethylene, graphite, nylon, and polyethylene oxide. The results indicated that the kerogen was similar to polyethylene oxide. The results of this study and previous work were used to present a model for the structure of the kerogen of Green River oil shale.     

Intangible assets as determinants of advanced manufacturingtechnology adoption in SME's: toward an evolutionary model

This paper investigates the relationship between intangible assets and further advanced manufacturing technology (AMT) adoption in 116 small manufacturing firms. Results indicate that the technical skills of blue-collar workers, the influence of customers and vendors, and strategic motivations focused on process improvement and customers are the strongest determinants of subsequent levels of adoption. Further, it is shown that strategic motivations moderate the relationships between technical skills and influences and further AMT adoption. Preliminary support for an evolutionary model is also found, leading to a revised conceptual framework     

Impact of cross-phase modulation for WDM systems over positive andnegative dispersion NZ-DSF and methods for its suppression

The impact of cross-phase modulation (XPM) is measured on positive and negative dispersion fibre. The exponential build-up of XPM over positive dispersion fibre indicates amplification due to modulation instability. Methods for suppressing XPM crosstalk are also demonstrated     

Timing jitter and pump-induced amplitude modulation in thecolliding-pulse mode-locked (CPM) laser

The timing jitter and spurious amplitude modulation of colliding-pulse mode-locked (CPM) lasers were measured. The absolute jitter (the jitter of the laser alone) varied between 5 and 10 ps RMS in a 50-500-Hz bandwidth. The smallest measured relative jitter (timing fluctuations between the CPM and a radio-frequency (RF) synthesizer synchronized to the CPM) was 1.8 ps RMS in a 2-Hz to 1-kHz bandwidth. Separate from the jitter, spurious modulation in the CW pump laser mixes with the CPM pulse train to produce a set of discrete amplitude-modulated sidebands in the power spectrum of the CPM output. The frequencies of these sidebands change with cavity length, and the sidebands can be eliminated by operating the pump laser in a single longitudinal mode     

News: Presidential "green chemistry" awards promote industrial pollution prevention

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