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This project involved adapting a Geo Metro to run on natural gas using fuel-injection technology. The stock electronic control unit and catalytic converter were used. The subcompact vehicle was equipped with a light-weight storage tank, a single-stage regulator, and a natural gas fuel injector which replaced the gasoline injector in the throttle body. The vehicle was tested for emissions using the U.S. Federal Test Procedure. The results indicate that we are close to meeting our objectives of developing a low-cost, environmentally friendly vehicle that runs on natural gas and that has a good driving range. The combined-cycle driving range was 498 km (309 mi). Tailpipe emissions at 10,000 km (6,200 mi) are presented for carbon monoxide, oxides of nitrogen, and non-methane hydrocarbons. In addition, data are presented on non-methane organic gas emissions based on hydrocarbon speciation tests, maximum incremental reactivities, and reactivity adjustment factors.

Some special features of cloud-to-ground (CG) lightning discharges in the verge of Qinghai-Tibetan Plateau have been found by using the data from wide-band slow antenna system with 1μs time resolution. It has been found that (CG) lightning usually follows intracloud (IC) discharges. K-changes during the IC discharge part initiate from negative charge region and propagate downward to the lower positive charge region with an average speed of 1.5×107 m/s. The radiation waveforms of return stoke begin with a slow front which last for about 9.4 μs to about half of the field peak amplitude, and the zero-to-peak rise time was 10.9μs for negative first return strokes.