Gunpowder was used in China as far back as the 11 th century.远在公元11世纪,中国已使用火药.A smell of gunpowder penetrated the woods.森林中弥漫着火药味.Gunpowder was introduced into Europe during the first half of the 14 th century.在14世纪上半叶,火...
由二苯并-1,3-二氧杂 - 环辛烷 -2- 羧酸经两步反应制得, 总收率70%.It was prepared by the reaction of 12 H - dibenzo [ d , g ] [ 1,3 ] dioxocin - 6 - carboxylic acid with acetoxime....
The flat tall and slender head lamp headlamp is glowering likely.扁平细长的大灯像在怒目而视.Correct defective components that could hinder proper headlamp alignment.修正故障组件会干扰头灯正确校正.Yesterday, I had to change a headlamp bulb on my car...