沥青混凝土摊铺,摊铺机必须缓慢、均匀、连续不间断地进行摊铺,摊铺速度宜为()m/mi

题型:单项选择题

问题:

沥青混凝土摊铺,摊铺机必须缓慢、均匀、连续不间断地进行摊铺,摊铺速度宜为()m/min。

A.2~6

B.4~8

C.8~12

D.10~20

考点:施工员施工员专业管理实务施工员专业管理实务题库
题型:单项选择题

下列关于生长曲线的叙述哪项不正确()

A.生长曲线是以时间为横坐标,培养物中的细菌数的对数为纵坐标,绘制而成的一条曲线

B.生长曲线可分为4期,即迟缓期、对数期、稳定期及衰亡期

C.生长曲线对研究工作及生产实践有指导意义

D.典型生长曲线可根据细菌在体内的生长特点而绘制

E.细菌在体内的生长曲线与其在培养基中的生长曲线有差异

题型:单项选择题

为了验证Cu、Zn、Fe的金属活动性顺序,甲、乙、丙三位同学进行下列探究,请你一起参与他们的活动:

提出假设:对于如何选择化学试剂问题,他们各抒己见.

(1)甲同学认为,应选的试剂是:Zn、FeCl2、Cu;

(2)乙同学认为,应选的试剂是:ZnCl2、Fe、CuSO4

(3)丙同学认为,只要分别将Cu、Zn、Fe投入稀盐酸中,根据它们产生的不同现象,同样也可以验证它们的金属活动性顺序.

你认为,他们选择试剂的方案中,可行的有______.(填以下序号)

A.甲同学       B.乙同学       C.丙同学

查阅资料:(1)不同的金属,活动性是不同的;有的金属能与酸起置换反应,有的则不能.(2)在相同条件下,金属活动性越强,与酸反应的速度越快.

实验探究:他们各自按自己选择的试剂进行探究.

(1)甲同学发现,把Zn、Cu分别投入FeCl2溶液中,只有______的表面才有黑色固体析出.

(2)乙同学发现,把Fe分别投入ZnCl2和CuSO4溶液中,只有在______溶液中Fe的表面才有固体析出.

(3)丙同学将Cu、Zn、Fe分别投入稀盐酸中,也得出同样的结论.你认为丙观察到的现象是:Cu的表面______(有、没有)气泡产生;丙同学所说的不同现象是指______.

实验结论:他们充分交流后,发现得出的结论相同,即Cu、Zn、Fe的金属活动性由强到弱的顺序是______.

题型:单项选择题

MOST recently, my world has been shaken by the death of a teacher at my school. He was Dr Allan Woolley and he was only 52. Suddenly he took his own life, which remains a mystery.

That morning, everyone sensed that something wasn't right. During our lessons, an announcement was made that an assembly (集会) was scheduled for morning break, which was only done in emergencies.

Once morning break came, the entire school gathered in the main hall. As our headmaster marched out to announce the "momentous (重大的) news", it felt like the air around us trembled . Many students broke down in tears, and the reaction afterward was intensely powerful and unifying .  

The headmaster said that students were allowed to miss lessons and have a free period to collect themselves if they found the news too distressing (悲伤的). Many students went outside and shared memories of Dr Woolley to control theirselves.

Dr Woolley taught me chemistry two years ago, but up until his death he still taught many of my close friends. Many of my friends were so shocked that they still couldn't believe the person that they had owed (欠) some homework to was now dead.

It was heart-warming to spend time with teachers that morning and get to know more about them. Despite the time of sadness, I feel that every cloud has a silver lining. Although Dr Woolley's death is something nobody wanted to see, we must move on.

小题1:What did the students feel at the news of his teacher’s death?

A.unhappy   B shocked    C.surprised    D.silent

小题2:What does the underlined word “collect” in Paragraph4 mean?

A.bring something together

B.calm down

C.increase in amount

D.get and keep小题3:Which of the following is NOT true according to the passage?

A.The real cause of Dr Woolley’s death is known to us.

B.Many students didn’t prepare themselves for the bad news so that they felt very sad.

C.It takes the whole school some time to recover from the dispressing news.

D.Dr Woolley’s death allows students to understand teachers better.小题4:It can be inferred from the underlined sentences in the last paregraph that______.

A.Dr Woolley’s death made students sad.

B.There is still some comfort and hope in trouble

C.Dr Woolley’s death disappointed students greatly

D.We should forget the fact to study better.小题5:The best title for the passage should be_______.

A.Our School Faces a Tragedy

B.Dr Woolley—A Great Teacher

C.The Living Live For the Death

D.Lesson From the Death.

题型:单项选择题

以下与淡白舌最无关的主证是

A.阴虚
B.气血亏虚
C.亡阳
D.阳虚
E.寒实

题型:单项选择题

导电液体在通电时发生分解的现象称为()

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