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- A hard mineral coating that forms on the inside surface of boilers, kettles, and other containers in which water is repeatedly heated. 锅垢在锅、壶和其它盛水器皿中经反复加热后在容器内壁形成的硬矿物质层
- An extremely hard mineral, aluminum oxide, Al2O3, sometimes containing iron, magnesia, or silica, that occurs in gem varieties such as ruby and sapphire and in a common black, brown, or blue form used chiefly in abrasives. 刚玉一种极为坚硬的矿物，氧化铝，Al2O3，有时含铁、氧化镁或硅土，存在于各种宝石中，如红宝石、蓝宝石，并且在磨蚀剂中以普通的黑色、棕色或蓝色形式出现
- A very hard mineral composed of silica,SiO2,found worldwide in many different types of rocks,including sandstone and granite. Varieties of quartz include agate,chalcedony,chert,flint,opal,and rock crystal. 石英由硅石组成的一种非常坚硬的矿物质，SiO2，广布世界各地，存在于许多不同种类的岩石中，包括沙岩和花岗岩。石英种类包括玛瑙、玉髓、黑矽石、燧石、蛋白石及水晶
- A very hard mineral composed of silica, SiO2, found worldwide in many different types of rocks, including sandstone and granite.Varieties of quartz include agate, chalcedony, chert, flint, opal, and rock crystal. 石英由硅石组成的一种非常坚硬的矿物质，SiO2，广布世界各地，存在于许多不同种类的岩石中，包括沙岩和花岗岩。石英种类包括玛瑙、玉髓、黑矽石、燧石、蛋白石及水晶
- A very hard mineral composed of silica, SiO2, found worldwide in many different types of rocks, including sandstone and granite. Varieties of quartz include agate, chalcedony, chert, flint, opal, and rock crystal. 石英由硅石组成的一种非常坚硬的矿物质，SiO2，广布世界各地，存在于许多不同种类的岩石中，包括沙岩和花岗岩。石英种类包括玛瑙、玉髓、黑矽石、燧石、蛋白石及水晶
- very hard mineral used as an abrasive. 一种极为坚硬的矿物，用作研磨剂。
- It is hard to sleep without a cooler in this room. 没有空气调节器，在这间屋里很难入睡。
- Applied technical specification for hard mineral wool board 硬质矿棉板应用技术规程
- John felt it hard to rig out his family. 约翰感到难以为一家大小置备衣着。
- The hard core in the party make all the decisions. 这个党的核心成员决定一切。
- Hard copy is computer output on paper, printing or graphics. 硬拷贝是出现在纸上、印刷上或图表上的电脑输出。
- I scrubbed hard at the stain to see if I could get it off. 我使劲擦这个污迹，看能不能将它去掉。
- It's natural to slack2 off towards the end of a hard day's work. 一天紧张工作快结束的时候有些放松是自然的。
- He pushed hard on the brake pedal to avoid a collision. 他使劲踩下煞车踏板以避免撞车。
- One can not learn a language well unless one works hard. 学好一种语言非下苦功不可。
- Let's collect the sap before its consolidation into a hard mass. 让我们在树液坚固成团之前将之收集起来。
- He owes his opulence to work hard. 他的财富乃辛勤工作得来。
- She was trying hard to disgorge a fish bone. 她拚命想把鱼刺吐出来。
- Main influ-encing factors on rock abrasiveness are the sturdiness of rock mass and contentof hard minerals,and the coefficient of rock abrasiveness is a function of thespecific energy consumption in drilling and the content of hard minerals. 影响岩石磨蚀性的主要因素是岩石的整体坚固程度和硬矿物含量。
- The emery is a hard metallic substance. 金刚砂是非常坚硬的金属物质。
