二级相变是指在相变时两相化学势相等,其一阶偏微熵也相等,而二阶偏微熵不等,因此二级相

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问题:

二级相变是指在相变时两相化学势相等,其一阶偏微熵也相等,而二阶偏微熵不等,因此二级相变()

A.有相变潜热,无体积的不连续性,有居里点

B.无相变潜热,有体积的不连续性,有居里点

C.无相变潜热,无体积的不连续性,无居里点

D.无相变潜热,无体积的不连续性,有居里点

考点:材料科学基础材料科学基础题库
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国家赔偿法规定,行政赔偿请求人请求行政赔偿的时效为2年,是从( )之日起算。

A.行政机关作出侵权行为

B.受害人知道侵权行为

C.侵权行为被确认为违法

D.受害人知道有赔偿请求权

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在天气、土壤、水域、生物受到严重污染的城市,工矿区以及河流与沿海地带多为各种环境性疾病的发病区。当代城市的“三废”污染与支气管炎、肺气肿、肺癌、食道癌、肠癌、胃癌和心血管疾病的发病率有着密切的关系。 这段话主要支持了这样一种观点( )。

A.沿海地带多为环境性疾病的发病区

B.环境污染严重地威胁着人类的健康

C.支气管炎是由“三废”污染引起的

D.食道癌、肠癌、胃癌和心血管病的发病率与城市的“三废”污染有着密切的关系

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外汇管制是一国政府通过()对国际结算和外汇买卖实现限制来平衡()和维持()的一种制度。

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当锅炉负荷突然()时,汽包水位先下降后上升。

A.增大

B.减小

C.不变

题型:单项选择题

Drug use is rising dramatically among the nation’s youth after a decade of decline. From 1993 to 1994, marijuana use among young people (1) from 12 to 17 jumped 50 percent. One in five high school seniors (2) marijuana daily. Monitoring the Future, which (3) student drug use annually, reports that negative attitudes about drugs have declined for the fourth year in a row. (4) young people see great risk in using drugs. Mood-altering pharmaceutical drugs are (5) new popularity among young people. Ritalin, (6) as a diet pill in the 1970s and now used to (7) hyperactive children, has become a (8) drug on college campuses. A central nervous system (9) , Ritalin can cause strokes, hypertension, and seizures. Rohypnol, produced in Europe as a (10) tranquilizer, lowers inhibitions and suppresses short-term memory, which has led to some women being raped by men they are going out with. (11) taken with alcohol, its effects are greatly (12) . Rock singer Kurt Cobain collapsed from an (13) of Rohypnol and champagne a month before he committed (14) in 1994. In Florida and Texas, Rohypnol has become widely abused among teens, who see the drug as a less expensive (15) for marijuana and LSD. Alcohol and tobacco use is increasing among teenagers, (16) younger adolescents. Each year, more than one million teens become regular smokers, (17) they cannot legally purchase tobacco. By 12th grade, one in three students smokes. In 1995, one in five 14-year-olds reported smoking regularly, a 33 percent jump (18) 1991. Drinking among 14-year-olds climbed 50 percent from 1992 to 1994, and all teens reported substantial increases in (19) drinking. In 1995, one in five 10th graders reported having been drunk in the past 30 days. Two-thirds of high school seniors say they know a (20) with a drinking problem.

4()

A.More

B.Many

C.Fewer

D.Few

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