偏钛酸钡(BaTiOx)因其显著地“压电效应”而广泛的应用于超声波发生装置中。已

题型:选择题

问题:

偏钛酸钡(BaTiOx)因其显著地“压电效应”而广泛的应用于超声波发生装置中。已知偏钛酸钡中钛元素的化合价为+4价,则其化学式中x的数值为[ ]

A. 1      

B. 2    

C. 3      

D. 4

考点:化合价的求法
题型:选择题

阅读理解

     Mrs. White was very fat. She weighed (重) 100 kilos, so she went to see a doctor. The doctor said,

"You need a diet (节食), Mrs. White, and I have a good way here." He gave Mrs. White a small book

and said, "Read this carefully and eat the things on page 11 every day. Then come back and see me in

two weeks."

     Mrs. White came again two weeks later, but she wasn't thinner. She was fatter than before. The

doctor was surprised and asked, "Are you eating the things on page 11 of the small book?" "Yes,

doctor." she answered.

     The next day the doctor visited Mrs. White during her dinner. He was very surprised at what he

saw. "Mrs. White,"  he said, "why are you eating potatoes and bread? They aren't in your diet."

"Doctor," Mrs. White answered, "I follow my diet at lunchtime. But this is my dinner."

1.Why did Mrs. White go to see a doctor?

A.Because she had a bad cold.

B.Because she felt terrible.

C.Because the doctor was her friend.

D.Because she wanted to be thinner.

2.The doctor asked her to _______.

A.eat more food

B.eat less food

C.eat nothing

D.eat healthy food

3.After two weeks,Mrs. White became _______.

A.fatter

B.thinner

C.healthier

D.stronger

4.Why was the doctor surprised when he visited Mrs. White during her dinner?

A.Because she eat nothing.

B.Because she was eating meat.

C.Because she was eating potatoes and bread.

D.Because she wasn't in.

5.What's the meaning of "I follow my diet at lunchtime. But this is my dinner."?

A.She always followed the diet.

B.She didn't follow the diet.

C.She didn't like the diet.

D.She only followed the diet at lunchtime, and she didn't follow the diet at dinner.

题型:选择题

每种东西都有它固定的颜色,有些是天然的,有些是人为的,但看惯了之后,就成了人类对颜色的概念。有人曾做过一个有趣的实验,利用无害的人工色素将各种食物染成奇怪的颜色,然后拿给一群小孩吃,当这群小孩吃下染成蓝色的马铃薯后,都觉得怪怪的,并出现肠胃不适或拉肚子症状。这说明[ ]

①打破约定俗成的东西是没有现实意义的

②一切事物的存在和发展都是有条件的

③人的认识与客观事物存在不可解决的矛盾

④打破约定俗成的东西不是件容易的事情

A、①②

B、②④

C、②③

D、③④

题型:选择题

肾移植患者感染最常见的病毒是()

A.HFRSV

B.HCMV

C.HIV

D.HPV

E.HSV

题型:选择题

毛细胞白血病 ()

A.酸性磷酸染色强阳性

B.糖原染色积分值增高

C.非特异性酯酶染色强阳性,酶活性可被氟化钠抑制

D.骨髓铁染色细胞内、外铁增加,有较多环形铁粒幼细胞

E.过氧化物酶染色阳性

题型:选择题

以下哪些设备可以不采用间接接触防护?()

A.处在伸臂范围以外墙上的架空线绝缘子支撑物和与其连接的金属部件(架空线金具)

B.采用双重绝缘或加强绝缘的电气设备

C.电气设备的外露可导电部分因其尺寸小或因其位置不会与人的身体的一部分有效接触,且与保护导体连接可靠时

D.触及不到钢筋的钢筋混凝土电杆

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