An attempt had been made to isolate and identify the low polar volatile constituents from Isodon excisa. The dried plants were heat extracted with ethanol and then extracted with petroleum ether. The constituents were...An attempt had been made to isolate and identify the low polar volatile constituents from Isodon excisa. The dried plants were heat extracted with ethanol and then extracted with petroleum ether. The constituents were isolated and analyzed by GC-MS and then we retrieved them on NIST08 mass spectrometry database to determine their structures. Finally, successful results were achieved, 111 compounds were obtained and identified. 105 of them were reported for the first time in lsodon excisa and 22 of them were first found in natural products. Thus, the main constituents of it were found to be Sitosterol （33.28%）, 3-Amino-4-pyrazolecarbonitrile （9.55%）展开更多
The present work studied fuel consumption through experiments on a diesel engine. In order to obtain lower BSFC （brake specific fuel consumption）, DME （dimethyl ether） is heated and introduced into air intake, tog...The present work studied fuel consumption through experiments on a diesel engine. In order to obtain lower BSFC （brake specific fuel consumption）, DME （dimethyl ether） is heated and introduced into air intake, together with fueling emulsified fuel to diesel engine. Results show that BSFC can decrease about 10% and diesel fuel consumption alone can decrease 18%. High saving rate of BSFC up to 10% is also acquired using ethanol instead of DME. To achieve high saving rate of BSFC, the heating temperature of about 1000 K is needed for DME operation, while the diesel engine exhaust temperature of about 750 K is suitable for ethanol. Hydrogen produced in DME or ethanol pyrolysis and the combustion characters of emulsified fuel are considered as main reasons for the excellent fuel saving. Besides, the technique adopted in the present work is extremely easy to be utilized, and may be firstly adopted on diesel engines for power plants, trains, and ships etc.展开更多
文摘An attempt had been made to isolate and identify the low polar volatile constituents from Isodon excisa. The dried plants were heat extracted with ethanol and then extracted with petroleum ether. The constituents were isolated and analyzed by GC-MS and then we retrieved them on NIST08 mass spectrometry database to determine their structures. Finally, successful results were achieved, 111 compounds were obtained and identified. 105 of them were reported for the first time in lsodon excisa and 22 of them were first found in natural products. Thus, the main constituents of it were found to be Sitosterol （33.28%）, 3-Amino-4-pyrazolecarbonitrile （9.55%）
文摘The present work studied fuel consumption through experiments on a diesel engine. In order to obtain lower BSFC （brake specific fuel consumption）, DME （dimethyl ether） is heated and introduced into air intake, together with fueling emulsified fuel to diesel engine. Results show that BSFC can decrease about 10% and diesel fuel consumption alone can decrease 18%. High saving rate of BSFC up to 10% is also acquired using ethanol instead of DME. To achieve high saving rate of BSFC, the heating temperature of about 1000 K is needed for DME operation, while the diesel engine exhaust temperature of about 750 K is suitable for ethanol. Hydrogen produced in DME or ethanol pyrolysis and the combustion characters of emulsified fuel are considered as main reasons for the excellent fuel saving. Besides, the technique adopted in the present work is extremely easy to be utilized, and may be firstly adopted on diesel engines for power plants, trains, and ships etc.
