In an age when waste today means a lack tomorrow, making use of every available resource becomes more and more important. As coal is being used in greater and greater amounts to produce electricity, larger amounts of ash, by-product of coal, are produced. When coal is burned in a boiler, two kinds of ash by-product are produced, a heavy bottom ash and a fine-as-powder fly ash that is filtered and captured by precipitators. About 10 to 15 percent of the coal by-product is bottom ash which is used like sand on icy city streets and highways and also on highways as paving material. It is the fly ash, however, that is receiving the greater amount of attention. Fly ash may be used as an additive to concrete in the construction of dams, bricks, and roads, and can replace up to 20 percent of the cement used in concrete. As a by-product of burned coal, fly ash requires no additional expenditure of energy to be produced, while cement production requires great amounts of energy.
In
A. Aluminum, silicon, and magnetic.
B. Additive.
C. Paving material.
D. Cement.
| Valentine’s Day is a festival of
romance and affection. The holiday is an interesting combination of pagan (异教徒的)
and Christian influences. Some of the day’s customs probably came from an
ancient Roman holiday caned Lupercalia, Which honored Juno (wife of Jupiter, the
goddess of women, marriage, and childbirth) and Pan (the God of nature). During
the Lupercalia festival, young women dropped poems bearing their names into a
large vase. Each young man picked a name from the vase to find his sweetheart
for that year. During the Middle Ages, church leaders wanted to relate this pagan holiday to Christianity, so they renamed it after a Christian saint and moved the holiday from February 15 to February 14, the feast day of St. Valentine. St. Valentine was a third-century Christian martyr, a young man who was imprisoned in Rome for r A. Valentine’s Day is only celebrated by adults B. Valentine’s Day is a religious as well as a secular (俗世的) holiday C. the customs of Valentine can be traced far back to an ancient Roman holiday D. it’s possible for someone to receive a gift on this particular day without knowing its sender [单选题]依据国家电网公司变电检测通用管理规定，检测班组现场工作结束并完成自验后，向（ ）报工作完结并介绍检测情况。
A.工作许可人 B.工作票签发人 C.工作负责人 D.当值运维人员 [多项选择]生产、经营、使用药品的单位( )
A. 应建立相应的管理制度，设置机构或配备人员。负责本单位药品不良反应情况的收集、报告和管理工作 B. 严格监测本单位生产、经营、使用的药品的不良反应发生情况 C. 一经发现可疑不良反应，需进行详细记录、调壹 D. 对严重、罕见或新的不良反应则须采取有效方式在15个工作日内快速报告 E. 对一般的药品不良反应每季度向所在地省级药品不良反应监测专业机构报告 [单项选择]可摘局部义齿制作中基托组织面不须做缓冲的部位是（）。
A. 上颌硬区 B. 上颌结节颊侧 C. 下颌舌隆凸 D. 内斜嵴 E. 磨牙后垫 [单选题]运输冷藏货物时以下说法错误的是_____。①乳制品应该冷冻运输;②装卸只能在夜间进行;③
装载冻牛油的货舱应用臭氧除臭 A. ②③ B. ①② C. ①③ D. ①②③ 我来回答: 提交
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