【判断题】
当产生火花放电后,再升高电压到一定值时,就会发生电晕放电
A. 对
B. 错
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答案
B
解析
暂无解析
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【判断题】
电除尘器在运行状态下,电场中的介质是烟气时的伏安特性称为空载伏安特性
A. 对
B. 错
【判断题】
释放电荷后的尘粒又靠残余电荷的静电力和分子吸引力相互聚集并且附着在阳极板的表面
A. 对
B. 错
【判断题】
电除尘器本体只包括阴极系统、阳极系统、槽形板系统、储排灰系统和管路系统
A. 对
B. 错
【判断题】
对极板振打力太大易引起二次扬尘并加速振打系统的机械损耗
A. 对
B. 错
【判断题】
高压硅整流变压器开路运行将产生高电压,危及设备和人身安全
A. 对
B. 错
【判断题】
硅整流变压器制造成高阻抗变压器,可提高回路阻抗电压,平滑波形,抑制谐波,减小铁损
A. 对
B. 错
【判断题】
阴、阳极采用不同的形状,目的是使它们之间产生不均匀电场
A. 对
B. 错
【判断题】
烟气温度低于露点时,造成高压部件绝缘降低,在低电压下就会产生严重的闪络
A. 对
B. 错
【判断题】
阴、阳极系统的所有螺栓、螺母除了应拧紧以外,还应点焊止转
A. 对
B. 错
【判断题】
从理论上讲,电晕线越细,其起晕电压越低
A. 对
B. 错
【判断题】
阻流板的作用是阻止烟气在电场中流速过快
A. 对
B. 错
【判断题】
控制火花放电可以采用火花频率控制或火花积分值控制的不同方式
A. 对
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【判断题】
电除尘器振打清灰周期越短,清灰效果越好,除尘效率越高
A. 对
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【判断题】
在电场灰斗中,一般保持1/2高度的储灰
A. 对
B. 错
【判断题】
阳极板一般采用周期振打,而阴极板一般采用连续振打
A. 对
B. 错
【判断题】
电除尘器的绝缘子加热恒温自动控制装置是为了保持绝缘支撑柱的干燥,避免因结露而产生闪络或拉弧短路
A. 对
B. 错
【判断题】
极板边缘应无锐边和毛刺,无局部放电现象
A. 对
B. 错
【判断题】
振打轴穿过侧板处应有良好的密封结构,否则会从外面大量漏风
A. 对
B. 错
【判断题】
在电除尘器的高压输入端有阻尼电阻,用以消除高频冲击振荡
A. 对
B. 错
【判断题】
电除尘器电场在负高压作用下的起晕功率比正高压高,而击穿电压又比正高压低
A. 对
B. 错
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高压硅整流变压器低压绕组外加设静电屏可提高绕组抗冲击的能力
A. 对
B. 错
【判断题】
在电除尘器顶部、大梁等均装有加热装置,其主要目的是为防结露
A. 对
B. 错
【判断题】
电除尘器的每次闪络,都将造成局部粉尘透过率减小
A. 对
B. 错
【判断题】
进行冷态伏安特性试验时,负电晕会产生臭氧,为消除臭氧对试验的影响,应启动引风机
A. 对
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【判断题】
收尘极板的有效高度(即除去上下两端夹持端板的收尘极高度)称为电场高度
A. 对
B. 错
【判断题】
电除尘器捕集下来的干灰经落灰管,一般直接落入灰沟
A. 对
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【判断题】
离心泵密封装置有填料密封,机械密封,迷宫式密封,浮动环密封
A. 对
B. 错
【判断题】
电除尘器的投运及停退与锅炉运行无关,只要锅炉运行可随时使之投入或停止
A. 对
B. 错
【判断题】
进入电除尘器本体内工作的人员,必须戴安全帽、防尘口罩、护目镜,穿绝缘鞋
A. 对
B. 错
【判断题】
启、停电除尘器、操作高压隔离开关时需穿绝缘鞋,戴绝缘手套
A. 对
B. 错
【判断题】
正常运行中高压硅整流变压器应无渗漏,油位、油温正常,油质合格,硅胶可变色
A. 对
B. 错
【判断题】
锅炉因检修而停炉,但电除尘器无检修工作时,应把高压隔离开关置于电场位置
A. 对
B. 错
【判断题】
瓷件保温箱内温度应比电除尘器室内烟气露点温度高20~30℃
A. 对
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电除尘器的工作电源应取自本单元机组的厂用电
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【判断题】
火力发电厂的能量转换过程为:燃料的化学能— 蒸汽热能— 机械能— 电能
A. 对
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除尘器漏风不仅增加引风机负担,还会影响锅炉的运行,但不影响除尘器效率
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运行中水泵电流表摆动,流量表摆动,说明该泵已发生汽化,但不严重
A. 对
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【判断题】
在电场灰斗中,一般保持1/3高度的储灰
A. 对
B. 错
【判断题】
当整流升压变压器出口限流电阻烧断时,表盘显示:一次电压很高,一次电流接近零,二次电压较低二次电流为零
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当整流升压变压器出口限流电阻烧断时,表盘显示:一次电压较低,一次电流接近零,二次电压(很高)二次电流为零
A. 对
B. 错
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What does the word “corrupt” in Para.4 mean?__________ ___
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What would be the best title of this passage?_____________ ___
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What is implied but not stated by the author is that ________. ___
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According to the passage, which of the following is NOT a disadvantage of part time education? _______________ ___
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Which of the following is NOT an advantage of distance learning? _________ ___
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Good distance learning program have the following characteristic EXCEPT______. ___
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What is the disadvantage of credit cards? _____________ ___
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