说明兆欧表的用途和使用方法。_爱下问搜题

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问题问答题简答题

说明兆欧表的用途和使用方法。

答案

参考答案：

兆欧表是测量电气设备绝缘电阻的仪表，它主要由手摇发电机和测试表头两部分组成，常用兆欧表的电压有500、1000、2500V三种规格。对于测额定电压在500V以下的电气设备的绝缘电阻，用500V或1000V兆欧表；对于额定电压在1000V以上的电器的绝缘电阻，用1000V或2500V兆欧表。兆欧表的接线柱有三个：L表示线；E表示地；G表示“保护环”。测电缆的芯线与外壳的电阻时，L与芯线相连，E与外壳相连，G与表面绝缘相连，以排除表面泄漏电流对测量结果的影响。

阅读理解

阅读理解。

Sarah lives in the country, and she loves playing in the river near her house. But her father gets a job

in a big city, and he moves there with his family.

Their new house has a garden, but the garden is very small. Sarah isn’t happy. "Is there a river near

here?" she asks her mother on the first morning. Her mother answers, “No, there isn’t, but there is a nice

park near here and there is a pool in it. We are going there this afternoon.” Sarah is happy now.

After lunch, Sarah and her mother go to the park. Sarah wants to walk near the pool, but there is a

sign(标志) before it. Her mother reads it to her, "Warning(警告): This pool is dangerous. 367 people

fell(跌倒) into it." Sarah looks into the pool carefully , and she says, "But I can’t see them."

1. Sarah likes playing _______ very much.

A. in the park

B. in the garden

C. in the river

2. Sarah’s father works _______.

A. in the country

B. in a big city

C. in a small city

3. There is _______ near Sarah’s new house.

A. a park

B. a garden

C. a zoo

4. Sarah goes to the park with _______.

A. her father

B. her mother

C. her teacher

5. Why can’t Sarah see the people in the pool?

A. Sarah’s mother doesn’t let her see.

B. She is too young.

C. There are no people in the pool.

多项选择题

金昌冶炼厂位于铜陵县境内，拟实施技术改造及污染治理工程。铜陵县地形兼有沿江平原与皖南山区之特点，地势南高北低，东部分低山丘陵。技改内容包括：熔炼系统——采用顶吹浸没式喷枪熔炼技术淘汰现有密闭鼓风炉；制酸系统——改造原有单转单吸制酸系统为双转双吸制酸工艺；火法精炼系统——淘汰1台50t固定式阳极反射炉，新建2台200t回转式阳极炉，并以液化气替代重油作还原剂；新增污酸处理站，改造现有污水处理工艺。设计规模为年产电解铜8万t(含铜99.95%)，硫酸32.71万t，粗铜8万，阳级铜10万t。技改后冶炼工艺包括备料配料——火法粗炼(顶吹浸没熔炼、沉淀炉分离、转炉吹炼)——火法精炼(回转式阳极炉)——电解精炼——熔炼炉、转炉烟气制酸。
项目排水进入章家洲小汊江，砷、重金属满足Ⅱ类水质标准，酚超Ⅳ类标准；小汊江汇入长江铜陵段，该段水质基本满足Ⅱ类水质标准，但按渔业水质标准要求，铜浓度超过0.01ms/L，超Ⅲ类水质渔业标准。评价区内SO₂和城区TSP均有超标，空气中重金属浓度未超标。现有熔炼系统SO₂无组织排放较严重。厂界噪声昼间和夜间均有超标现象。评价区土壤中Cu、Zn、Cd含量超过《土壤环境质量标准》二级标准；稻谷样品中，Cu、Pb、As含量超标。
根据以上内容，回答以下问题。

铜冶炼项目环评中应关注( )。

A．无组织排放污染问题

B．制酸系统运行稳定性

C．砷污染

D．卫生防护距离的确定