关于流动边界层,下列说法不正确的是()。A、边界层沿厚度方向有急剧的速度变化 B、边界

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问题:

关于流动边界层,下列说法不正确的是()。

A、边界层沿厚度方向有急剧的速度变化

B、边界层外的外部流动区域,粘性影响可以忽略不计

C、边界层内粘性力和惯性力具有相同的数量级

D、在物体附近的边界层的流动区域,粘性影响可以忽略不计

考点:输油工考试输油工中级输油工中级题库
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Sarah lives in the country, and she loves playing in the river near her house. But her father gets a new job in a big city, so she moves there with her parents. 

Their new house has a garden, but the garden is very small. Sarah is not happy in the new house.

“Is there a river near here?” she asks her mother in the morning. Her mother answers, “No, there isn’t. But there is a nice park near here and there is a pool(水池) in it. Shall we go there this afternoon?” Sarah is happy.

After lunch, Sarah and her mother go to the park. Sarah wants to play near the pool, but there is a sign (标记) before it. Her mother reads it to her, “Warning (警告): This pool is dangerous. Twenty people fall into (掉进) it.” Sarah looks into the pool carefully, and says, “But I can’t see them.”

小题1:Sarah’s father works __________ now.    

A.in a big city

B.on a big farm

C.in the village

D.in a town小题2:In the new house, there is ________ but it’s __________.

A.a river; long

B.a garden; small

C.a park; big

D.a pool; clean小题3:Sarah goes to the park with her mother ___________.

A.in the morning

B.at noon

C.in the afternoon

D.in the evening小题4:Which of the following is NOT right?

A.Sarah’s family move to the big city.

B.Sarah is not happy in her new house.

C.In the park, there is a pool in it.

D.There are twenty people in the pool.

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Ⅱ类洞的邻面窝洞制备要点()

A.颊、舌壁洞形应扩展到外展隙

B.颊、舌壁微向咬合面方向聚合

C.颊、舌壁应顺釉柱方向稍外敞

D.颊、舌两侧的轴髓线角要圆钝

E.颊、舌两侧的龈线角清晰锐利

题型:单项选择题

___________catch the first train, he asks his mother to awake him up in the morning

A So as to        B In order to       C So that       D In order that

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病历摘要:某男,28岁,右眼红痛、视力下降三天,不伴有头痛,无恶心呕吐症状,在当地医院口服抗菌素与止痛药,症状无明显改善,曾自行应用过消炎类眼药水。否认眼外伤史与药物过敏史,家族中无类似病史。

你认为采用何种措施较为妥当?()提示:病者在裂隙灯下,角膜轻度水肿,角膜后KP阳性,前房可见明显闪辉,瞳孔极小,部份后粘连,结膜为睫状充血。血常规与尿常规无异常,胸片未见异常。

A.全身应用类固醇类激素

B.局部应用较强力类固醇类激素

C.强有力散瞳

D.口服一些维生素

E.口服大量抗菌素

F.口服一些止痛类药物

G.加强运动达到加速疾病痊愈

H.采用物理疗法

I.采用强有力免疫抑制剂

题型:单项选择题

芦荟具有一种特殊的CO2同化方式:夜间气孔开放,吸收CO2转化成苹果酸储存在液泡中;白天气孔关闭,液泡中的苹果酸分解释放CO2参与光合作用,如图一、图二。芥兰的CO2利用过程如图三,请据图回答问题:

在温室中,如果保持光照强度不变,需要进一步提芥兰的高光合速率,可采取的措施是()

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