The carbon is electrophilic centre.碳是亲电的中心.It will become deepen to the students'recognization in mechanism of Aryl electrophilic substitution.这些问题的讨论将深化学生对芳烃亲电取代反应机理的认识.The rate constants of radical and electrophil...
Some soldiers went on furlough for two weeks.有些士兵休假两周.I was at home on furlough.我正休假在家。I have a furlough every three years.我每三年休假一次.This could mean a massive furlough of government workers.这可能意味着大量的政府工作人员要暂时下岗。...
The bullhorn acacia is not a tree of the dark windless depths of the tropical rain - forest.牛角相思树不喜欢在阴暗不透风茂密的热带林区中生长.The bullhorn acacia has serious competition.牛角相思树面临着严峻的挑战.He lives at 9, Acacia Gardens.他住在金合欢街9号。Park ...
The police cordoned everything off.警察将一切都封锁了。Police cordoned off part of the city centre.警察封锁了市中心的部分地区。Police cordoned off the road and diverted commuter traffic.警察封锁了道路并分流交通....
对切花品质的评价受主、客观因素的影响,而且评价标准也是可变的.Quality evaluation of cut flower is affected by subjective and objective factors.而Y2O3既可作为施主, 又可起受主作用.Y 2 O 3 acts not only as a donor, but also as an acceptor.受主 - 一种用来在半导体中形成空穴的元素, 比如硼 、 ...