某新建2×300MW燃煤发电厂,高压厂用电系统标称电压为6kV,其中性点为高电阻接地

题型:单项选择题 案例分析题

问题:

某新建2×300MW燃煤发电厂,高压厂用电系统标称电压为6kV,其中性点为高电阻接地。每台机组设两台高压厂用无励磁调压双卷变压器,容量为35MVA,阻抗值为10.5%,6.3kV单母线接线,设A段、B段。6kV电统电缆选为ZRYJV226/6kV三芯电缆

注:1.表中导体尺寸中h为宽度,b为厚度。2.表中当导体为四条时,平放、竖放第2、3条间距皆为50mm。3.相同截面的铜导体载流量为表中铝导体载流量的1.27倍。请根据上述条件计算下列各题(保留两位小数)。

清在下列选项中选择最经济合理的6.3kV段母线导体组合,并说明理由()。

A.100×10矩形铜导体二条平放

B.100×8矩形铝导体三条竖放

C.100×6.3矩形铜导体三条平放

D.100×10矩形铝导体三条竖放

考点:电气工程师(发输变电)发电厂和变电所用电发电厂和变电所用电题库
题型:单项选择题 案例分析题

女,39岁,洗澡时发现左乳包块,无痛。 3年前因肺结核住院治疗。体检:左 * * 外上象限略高于右 * * 外上象限,皮肤稍皱褶,局部可扪及直径为1.5cm大小肿块,质硬,表面不甚光滑,边界欠清,可活动,左腋下可扪及肿大淋巴结。胸透示陈旧性结核灶

如果为了进一步明确诊断,应采取下列哪项检查

A. * * 钼靶摄片

B.肿块切除活检

C.CT

D.B超

E.放射性核素扫描检查

题型:单项选择题 案例分析题

根据首字母及中文填写正确的单词(共10小题;每小题0.5分,满分5分)

1. I could see a tall f_______ over there, but when I came near, I found it wasn’t a person.

2. After a few days’ stay in hospital, Mr. Green r_______  from his illness. 

3. In China, young children are usually taught to r_______ the old people.

4. He is a f_______ as an artist, but a success as an art teacher.

5. After g_____________ from university, he worked as a newspaper reporter.

6. The students are making p__________ for the coming mid- examination.    

7. Attention should be paid to m_______ good use of English newspapers rather than selling materials to students.

8. I am trying to lose weight because I’m so a________ of my body.

9. The children had an a_______ about what game to play, but they reached an agreement in the end.

10. He is so shy that he often feels e____________ about making speeches in public.

题型:单项选择题 案例分析题

《传染病防治法》规定的甲类传染病是指

A.鼠疫、霍乱

B.鼠疫、传染性非典型肺炎

C.霍乱、传染性非典型肺炎

D.传染性非典型肺炎、人感染高致病性禽流感

E.流行性出血热、艾滋病

题型:单项选择题 案例分析题

男,25岁,突然剧烈头痛、呕吐3h入院。有偏头痛史8年。体检:神志清楚,颈抵抗,凯尔尼格(Kernig)征阳性。四肢肌力正常。

不正确的治疗是()

A.卧床休息

B.静滴20%甘露醇

C.应用止血药

D.抗血栓治疗

E.尼莫地平

题型:单项选择题 案例分析题

胶合板的层数可以是双数,也可以是单数,可根据工程情况选用不同的品种。

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