某110kV变电站采用全户内布置,站内有两台主变压器,110kV采用中性点直接接地方

题型:单项选择题 案例分析题

问题:

某110kV变电站采用全户内布置,站内有两台主变压器,110kV采用中性点直接接地方式。变电站内仅设一座综合建筑物,建筑物长54m、宽20m、高18m,全站围墙长73m、宽40m。变电站平面布置如图所示,请回答下列问题。

该变电站110kV配电装置保护接地的接地电阻R应满足下列哪一项?并说明依据和理由()。(式中,I为计算用的流经接地装置的入地短路电流)

A.R≤2000/I

B.R≤250/I

C.R≤120/I

D.R≤50/I

考点:电气工程师(发输变电)接地接地题库
题型:单项选择题 案例分析题

-Who's that speaking?    

-Jane!    

-Jane! Oh yes. Sorry, I _______ recognize your voice.   [      ]

A. haven't

B. won't  

C. didn't

D. don't

题型:单项选择题 案例分析题

(化学-选修有机化学基础)

已知一个碳原子上连有两个羟基时,其结构极不稳定,易发生下列变化,生成较稳定物质:如:

A-F是六种有机化合物,它们之间的关系如下图,请根据要求回答:

(1)在一定条件下,经反应①后,生成C和D,C的分子式为______,反应①的类型为______.

(2)反应③的化学方程式为______.

(3)已知B的相对分子质量为162,其完全燃烧的产物中n(CO2):n (H2O)=2:1,则B的分子式为______.

(4)F是高分子光阻剂生产中的主要原料.F具有如下特点:①能跟FeCl3溶液发生显色反应;②能发生加聚反应;③苯环上的一氯代物只有两种.F在一定条件下发生加聚反应的化学方程式为______.

(5)化合物G是F的同分异构体,属于芳香族化合物,能发生银镜反应.G有______种结构,写出其中一种同分异构体的结构简式______.

题型:单项选择题 案例分析题

为了防止曲轴扭振过大,在曲轴的前端装有()。

A.减振器

B.防振块

C.耐磨块

D.消声器

题型:单项选择题 案例分析题

Speech, whether oral or written, is a used commodity. If we are to be heard, we must (1) our words from those (2) to us within families, peer groups, societal institutions, and political networks. Our utterances position us both in an immediate social dialogue (3) our addressee and, simultaneously, in a larger ideological one (4) by history and society. We speak as an individual and also, as a student or teacher, a husband or wife, a person of a particular discipline, social class, religion, race, or other socially constructed (5) . Thus, to varying degrees, all speaking is a (6) of others’ words and all writing is rewriting. As language (7) , we experience individual agency by infusing our own intentions (8) other people’s words, and this can be very hard.

(9) , schools, like into churches and courtrooms, are places (10) people speak words that are more important than they are. The words of a particular discipline, like those of "God the father" or of "the law," are being articulated by spokespeople for the given authority. The (11) of the addressed, the listener, is to acknowledge the words and their (12) . In Bakhtin’s (13) , "the authoritative word is located in a distanced zone, organically connected with a (14) that is felt to be hierarchally higher."

(15) , part of growing up in an ideological sense is becoming more "selective" about the words we appropriate and, (16) , pass on to others. In Bakhtin’s (17) , responsible people do not treat (18) as givens, they treat them as utterances, spoken by particular people located in specific ways in the social landscape. Becoming alive to the socio-ideological complexity of language use is (19) to becoming a more responsive language user and, potentially, a more playful one too, able to use a (20) of social voices, of perspectives, in articulating one’s own ideas.

Read the following text. Choose the best word(s) for each numbered blank and mark A, B, C or D on ANSWER SHEET 1.8()

A.out of

B.onto

C.away from

D.into

题型:单项选择题 案例分析题

“应付账款”账户的期初余额为8000元,本期贷方发生额为12000元,期末余额为6000元,则该账户的本期借方发生额为()元。

A.2000

B.4000

C.10000

D.14000

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