【单选题】What is aim of lamination in dry outer film of PCB production process?
A.
To remove some contaminants on the copper surface, increasing surface roughness of copper
B.
To create photo resist layer on outer layer for pattern creation
C.
To transfer the original film image onto a photo sensitive plate by light irradiation
D.
To make sure the vias connecting different inner layers smooth and bare,make it easier for Panel plating.
【单选题】What is aim of pattern plating in outer layer of PCB production process?
A.
To remove some contaminants on the copper surface, increasing surface roughness of copper
B.
To transfer the original film image onto a photo sensitive plate by light irradiation
C.
To protect copper from corrosion
D.
To increase copper thickness after the procedure of developing
【单选题】下列说法正确的是
A.
在氧化还原反应中,若两个电对的标准电极电势 值相差越大,则反应进行得越快。
C.
某物质的电极电势代数值越小,说明它的还原性越强
D.
标准电极电势值越大则电对中氧化型物质的氧化能力越强
【简答题】电动放风阀属于阀口式空气阀, 它由( )与 ( ) 两部分组成。
【判断题】在氧化还原反应中,两电对的标准电极电势值相差越大,反应进行得越快。
【简答题】妇产科腹部手术时备皮范围上自____________,两侧至____________,下达____________。外阴和阴道手术时备皮范围上至____________,下至____________,包括腹股沟、外阴和大腿上1/3。
【简答题】妇产科手术中腹部手术与外阴、阴道手术患者术前备皮范围?
【判断题】在签订保险合同时,保险代理所知晓的事情都视保险人已知( )
【判断题】在氧化还原反应中,若两个电对的标准电极电势值相差越大,则反应进行得越快。