【单选题】辐射育种中应用最普遍的放射性 60 钴或 137 铯,它们产生的高能射线是()。
【简答题】a. (usu. before noun) not real or not made of natural things 人造的;人工的;假的
【简答题】A.Diet has nothing to do with health. B.The amount of food has something to do with health. C.Health depends on diet totally. D.Good food has nothing to do with health.
【简答题】a. (not before noun) wanting to do sth. 有...意向的;倾向于...的
【判断题】当测试三极管的正向特性时,集电极电源的“功耗限制电阻”旋钮应置于高阻挡。( )
【单选题】假设P0端口的方向寄存器用P0DIR表示,该寄存器有8位,每个位对应P0的8个管脚的输入/输出方向:对应位为0表示输入,1表示输出。那么要将P0的管脚1和5同时设置为输入的方法是?
A.
P0 = P0 | ((1<< 1) | (1<<5))
B.
P0 = P0 | ~((1<< 1) | (1<<5))
C.
P0 = P0 & ~((1<< 1) | (1<<5))
D.
P0 = P0 & ((1<< 1) | (1<<5))
【判断题】晶体管特性图示仪当测试三极管的正向特性时,集电极电源的“功耗限制电阻”旋钮应置于高阻挡。( )
【单选题】高精度的零件,一般在粗加工之后,精加工之前进行( ),减少或消除工件内应力。