【简答题】有一个电炉,炉丝长50m,炉丝用镍铬丝,若炉丝电阻为5Ω,问这根炉丝的截面积是多大?(镍铬丝的电阻率取1.1×10 -6 Ω·m)
【单选题】钢结构是由钢材制作的结构,包括钢框架结构、钢网架结构和钢网壳结构、大跨交叉梁系结构,其最大缺点是( )。
【单选题】35 The writer cites the Duomo in the last paragraph as an example to illustrate that
A.
there is a tight link between church and society.
B.
all churches are magnificent.
C.
old churches are very popular.
D.
high-rise churches are impressive.
【单选题】某管线输送含蜡原油,首站将所输原油进行80℃热处理,因为输送过程中管道中原油沿途温降,经过某中间站加热炉又将原油加热到50℃,结果将使原油()。
【单选题】According to Paragraph 2, you must be well informed of weather conditions when hiking there because______.
A.
the weather there is bad
B.
the canyon is too long
C.
the flood there is dangerous
【单选题】45 The writer cites the Duomo in the last paragraph as an example to illustrate that
A.
there is a tight link between church and society.
B.
all churches are magnificent.
C.
old churches are very popular.
D.
high—rise churches are impressive.
【单选题】含蜡原油的最佳热处理温度是:必须将原油加热到使原油中的石蜡和胶质一沥青质(),其处理结果是原油的凝点、粘度都要下降。
【单选题】含蜡原油热处理的内在因素是蜡和胶质,其处理的外部条件则是()等。
【单选题】有“中华古代道教建筑的露天博物馆”之誉的是( )。