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- Diosgenin is the hydrolyzed material of dioscin and the precursor substance of several important endogenous steroids. 摘要薯蓣皂甙元是薯蓣皂甙的水解产物，它是许多重要甾体激素的前体物质。
- Analysis showed a negative correlation of mass concentration between NO2 and O3 and confirmed that NO2 is important precursor substance of O3 . O3与NO2呈现负相关性,验证了NO2是生成O3的重要前体污染物。
- It's known that: YE is a new international condiment derived from natural edible yeast, as well as the nutritional delicious precursor substance rich in nucleotides, inosinic acid, guanylic acid, etc. 据悉：YE是源自天然食用酵母的国际新型调味料，含有丰富的核苷酸、肌苷酸、鸟甘酸等营养型美味前体物质。
- The emery is a hard metallic substance. 金刚砂是非常坚硬的金属物质。
- Barium sulfate is a radiopaque substance. 钡硫酸盐是一种辐射光不能穿透的物质。
- Musk is a kind of strong-smelling substance. 麝香是一种有强烈气味的物质。
- Graphite is a soft black substance. 石墨是一种软而黑的物质。
- The precursor of the modern car was a horseless carriage with a petrol engine. 现代汽车的前身是不用马拉的，装有汽油发动机的车子。
- This substance is soluble in alcohol. 这种物质能够溶解在酒精中。
- Her account was in substance correct. 她的账目基本上是对的。
- Ammonia is a chemical substance. 氨是种化学物质。
- The substance is irritable to sensitive skin. 这种物质对敏感的皮肤有刺激性。
- An inert substance used to dilute. 稀释剂一种惰性物质
- The question was never discussed in substance. 这问题实际上从来没有讨论过。
- Gelatin is a clear tasteless substance. 明胶是一种透明无味的物质。
- This substance is extracted from seaweed. 这种物质是从海藻中提取的。
- This substance must be treated with acid. 这材料得用酸来处理。
- They maintained that ghosts had no substance. 他们认为鬼魂不是实物。
- A substance believed to maintain life indefinitely. 长生不老药被认为可以使生命无限的物质
- Thefirst telephone was the precursor of modern communications networks. 最早出现的电话是现代通讯网的雏型。
