介绍了丙二酰氧基硼氢化钾的制备及其原位与烯烃的选择性硼氢化.The preparation of potassium malonyloxyborohydride in situ and its selective hydroboration alkene are described.叙述了丙二酰氧基硼氢化钠的制备及其原位与烯烃的选择性硼氢化反应.The preparation of sodium malonyloxyborohydrid...
要确定事态演变的明确结果,并不容易.It is not easy to establish the exact sequence of events.他论证说,生物是由于一些小的遗传变异的积累而逐渐演变的.He argued that organisms evolve gradually by accumulating small hereditary changes.每项发展都是而且将来也是逐渐演变的.Each development...