On the basis porous carbon , the reactive sintering silicon carbide ceramics were prepared by ihrigizing reaction.以此为基础, 进一步通过渗硅反应,制成反应烧结碳化硅陶瓷.The effect of the sintering temperature on the degrease performance is obviou...
He is vacuuming a rug in the sitting room.他在起居室里用吸尘器打扫地毯.L am vacuuming the floor now and have several shirts to iron.我正在用真空吸尘器清理地板,还有好几件衬衫要熨.But a wide - open floor adds only a few seconds the vacuuming chore.但是,广泛的开放式购...
Here the Nile broadens out between the huge granite boulders.尼罗河在此处变宽，从两块花岗岩巨石间穿过。The Aswan Dam helps to control the River Nile in Egypt.阿斯旺水坝有助于控制埃及的尼罗河.Explorers traced the Nile River to its several headstreams in Cent...
Limpets, snails and octopuses are mollusks.帽贝 、 蜗牛和章鱼都是软体动物.I think I’ll try the snails for lunch—I’m feeling adventurous today.我想我午餐要尝一下蜗牛——我今天很想冒险。The snails are no larger than one centimetre across.这些蜗牛体宽不超过1厘米。These ...