The title reaction was studied in a crossed-beam experiment, in which the ground-state methyl products were probed using a time-sliced velocity-imaging technique. By taking images over the energy range of chemical significance, from the threshold to about 15 kcal mol(-1), the reactive excitation function as well as the dependences of product angular distributions and of the energy disposal on initial collision energies were determined. All experimental data are consistent with the picture that the ground-state reaction of O((3)P)+CH(4) proceeds via a direct abstraction rebound-type mechanism with a narrow cone of acceptance. Deeper insights into the underlying mechanism and the key feature of the potential-energy surface are elucidated by comparing the results with the corresponding observables in the analogous Cl+CH(4) reaction.

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The possibility of a spectrally tunable solar-like light source is drawing attention with the development of LEDs. We researched the market of high-power, monochromatic LEDs and established a database with 103 kinds of LED by a new model. We used the database to match the solar spectrum in the wavelength range 380-780 nm. The optimal combination maximising the fit to the solar spectral curve was obtained. The trade-off relationship between the selection of LEDs and the fit was investigated in detail. The results show that the optimal combination contains 34 types of LED with a maximum correlation index R 2 of 88.67%. The value of R 2 reduces to 85.06% when the number of LED types is reduced to 20, but the R 2 value decreases sharply if the number of LED types is decreased to 16, with a R 2 of 79.97%.

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