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【简答题】
Priscilla Ouchida’s energy-efficient” house turned out to be a horrible dream. When she and her engineer husband married a few years ago, they built a $ 100 000, three-bedroom home in California. Tightly sealed to prevent air leaks, the house was equipped with small double-paned(双层玻璃的)windows and several other energy-saving features. Problems began as soon as the couple moved in, however. Priscilla’s eyes burned. Her throat was constantly dry. She suffered from headaches and could hardly sleep. It was as though she had suddenly developed a strange illness. Experts finally traced the cause of her illness. The level of formaldehyde(甲醛)gas in her kitchen was twice the maximum allowed by federal standards for chemical workers. The source of the gas? Her new kitchen cabinets and wall-to-wall carpeting. The Ouchidas are victims of indoor air pollution, which is not given sufficient attention party because of the nation’s drive to save energy. The problem itself isn’t new. “The indoor environment was dirty long before energy conservation came along,” says Moschandreas, a pollution scientist at Geomet Technologies in Maryland. “Energy conservation has tended to accentuate the situation in some cases.” The problem appears to be more troublesome in newly constructed homes rather than old ones. Back in the days when energy was cheap, home builders didn’t worry much about unsealed cracks. Because of such leaks, the air in an average home was replaced by fresh outdoor air about once an hour. As a result, the pollutants generated in most households seldom built up to dangerous levels.
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举一反三
【单选题】派中的()和()选择了追随。
A.
民革、
B.
青年党、民盟
C.
青年党、
D.
民革、民盟
【多选题】每1ml乙二胺四醋酸二钠滴定液(0.05mol/L)相当于葡萄糖酸钙22.42mg( )
A.
葡萄糖酸钙是被测物质,乙二胺四醋酸二钠是滴定剂
B.
是滴定度的含义
C.
可以用符号T 表示,是用于计算的
D.
可以表示为22.42mg/ml
【单选题】乙二胺四醋酸二钠滴定液(0.05mol/L)配制及标定过程中不使用下列哪种试剂( )。
A.
氧化锌
B.
氨试液
C.
荧光黄
D.
铬黑T
E.
稀盐酸
【简答题】乳酸钙片(规格为0.5g)的含量测定方法:精密称取本品10片,重量为6.0320g,研细,精密称取片粉0.3587g,按药典规定进行测定,消耗乙二胺四醋酸二钠滴定液(0.0501 mol/L)18.92mL。每1mL乙二胺四醋酸二钠滴定液(0.05mol/L)相当于15.40mg的 C6H106·5H2O。计算乳酸钙含量占标示量的百分率。
【单选题】职业道德范畴是反映职业道德现象的特性、方面和关系的基本概念,以下不属于社会主义职业道德范畴的是( )。
A.
职业理想
B.
职业荣誉
C.
职业习惯
D.
职业幸福
【简答题】低压电器按操作方式分为 和自动两种操作方式 。
【单选题】职业道德范畴是反映职业道德现象的特性、方面和关系的基本概念,以下不属于社会主义职业道德范畴的是( )。
A.
职业幸福
B.
职业理想
C.
职业习惯
D.
职业荣誉
【单选题】对行驶速度为( )km/h的车辆实施紧急制动,可验证安全带是否起作用
A.
10~25
B.
20~35
C.
30~45
【简答题】低压电器按操作方式分为( )电器和( )电器
【简答题】精密称取本品细粉0.1279g ,置锥形瓶中 ,加稀盐酸 3ml,加热至微沸使溶解 ,加水 100ml与甲基红指示液 1 滴 ,滴加氢氧化钾试液至显黄色,继 续 多 加 10ml,再加钙黄绿素指 示 剂 少 量 ,用 乙 二 胺 四 醋 酸 二 钠 滴 定 液 (0.05mol/L)滴 定 至 溶 液 黄 绿 色 荧 光 消 失 而 显 橙 色 。每 lml乙 二 胺 四 醋 酸二 钠滴 定液(0...
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