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31.
Low tropospheric wind measurement with Mie Doppler Lidar 总被引:3,自引:0,他引:3
A double edge Mie Doppler lidar at 1064 nm was developed in Hefei, China in 2005 for low tropospheric wind measurement. Intercomparison
experiments with a wind profiler and a wiresonde were held. Intercomparisons of concurrent lidar and other instrument observations
show good agreement with expected measurement accuracy. The examples of validated lidar wind profiles obtained during these
experiments as well as an example of continuous wind observations are presented. The instrument has demonstrated the capability
of atmospheric wind field measurement from 0.2 to 5 km altitude, achieving below 2 m/s accuracy with 1 min averaging and 21.2
m vertical resolution. 相似文献
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Choi WJ Moon HR Kim HO Yoo BN Lee JA Shin DH Jeong LS 《The Journal of organic chemistry》2004,69(7):2634-2636
The preparative and stereoselective synthesis (45-50% overall yields) of the target compound 17 has been accomplished from D-ribose. The bulky protecting groups such as TBDPS and Trityl enforced the facial selectivity during Grignard reaction to give the tertiary beta-allylic alcohol 16 as the sole product, which was oxidatively rearranged to the key molecule 17 in excellent yield. 相似文献
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A novel tandem one-pot method for the synthesis of α-aminomethylene-γ-butyrolactone derivatives has been developed through the regioselective epoxide opening reactions with the Blaise reaction intermediates, generated by the reaction of a Reformatsky reagent with nitriles. Formation of a modified Blaise reaction intermediate by the addition of a stoichiometric amount of n-BuLi followed by slow addition of epoxide is required for the good yield of γ-butyrolactones. 相似文献
40.
Jong Ho Lee Sung Bong Kim Chulhwan Park Bumseok Tae Sung Ok Han Seung Wook Kim 《Applied biochemistry and biotechnology》2010,161(1-8):365-371
In this study, transesterification and esterification were investigated in batch and continuous process using immobilized Candida rugosa and Rhizopus oryzae lipases. In the case of batch process, stepwise reaction method was investigated to prevent the lipase deactivation. Reaction conditions were as follows: temperature, 45 °C; agitation speed, 250 rpm; enzyme concentration, 20%; and water contents 10%. And then, conversion yield was 98.33% at 4 h. In the case of continuous process, circulation and long-term continuous system were investigated for development of efficient mass transfer system. Optimal reaction conditions were as follows: temperature, 45 °C; flow rate, 0.8 mL/min; and water contents, 10%. And then, conversion yield of biodiesel was 97.98% at 3 h. Especially, the maximum conversion yield using a mixture of immobilized lipases exceeded over 90% for 108 h in long-term continuous system under optimal reaction conditions (45 °C; flow rate, 0.8 mL/min; and water contents, 10%). These results should help in determining the best method for the biodiesel production and improving the design and operation of large scale by enzymatic systems. 相似文献