【单选题】下列关于加油油气回收系统描述不正确的是()。
A.
油气分离接头是用来分离油气和液体汽油通路的转换接头
C.
同轴皮管将油路与气路设在一条皮管,内管为气路,外管为油路
D.
拉断阀用来防止车辆将加油机拉倒,不能重复使用
【简答题】Lucy, Mary, Tom and Tony are good friends. They are in Class 4, Grade 1. Tom’s favourite subject is maths. Lucy’s favourite subject is English. Mary’s favourite subject is Chinese. Tony likes P.E. bes...
【简答题】阅读理解。 Lucy, Mary, Tom and Tony are good friends. They are in Class 4, Grade 1. Tom's favourite subject is maths. Lucy's favourite subject is English. Mary's favourite subject is Chinese. Tony likes P....
【单选题】有关单稳态触发器的描述不正确的是?
C.
单稳态触发器在外界触发信号作用下,能从稳态→暂稳态,维持一段时间后自动返回稳态
D.
单稳态触发器的暂稳态维持的时间长短取决于电路内部参数
【简答题】高效液相色谱法外标法测定头孢氨苄的含量。取含量为 99.8% 的头孢氨苄对照品 20.40mg 配成溶液,取该溶液 10μl 进样,测定峰面积,面积的平均值为 300000 ; 另取头孢唑啉钠供试品 20.02mg ,同法处理并测定,测得峰面积平均值为 290000 ,求供试品的含量。
【单选题】(C) 信息匹配。阅读5段描述和5条相关的信息,将这些描述和相应的信息匹配起来,并把与信息对应的字母填写在括号内。 The following information shows a list of job descriptions. Decide which person does the job. ( 下面是各人对自己工作内容的说明 , 请将这些说明与相应的人匹配。 ) ( ) 67. ...
A.
I receive cash from customers and pay out money.
B.
I prepare food for customers.
C.
I take customer’s order and bring food and drinks to them.
D.
I put off fire and try to save people’s lives.
E.
I take care of the patients and help them recover.
【简答题】随着焊接速度的变快,焊缝会变___(宽/窄),余高会___(增大/减小)。