“天宫一号”飞行器在太空工作期间必须有源源不断的电源供应。其供电原理是:白天太阳能帆板发电,将一部分电量直接供给天宫一号,另一部分电量储存在镍氢电池里,供黑夜时使用。下图为镍氢电池构造示意图(氢化物电极为储氢金属,可看做H2直接参加反应)。下列说法正确的是
A.充电时阴极区电解质溶液pH降低 |
B.充电时阳极反应为:Ni(OH)2-e-+OH-==NiOOH+H2O |
C.放电时NiOOH在电极上发生氧化反应 |
D.在使用过程中此电池要不断补充水 |
They use computers to keep the traffic _______ smoothly.
A.being run | B.run | C.to run | D.running |
If you leave the club, you will not be_____back in .
A.received | B.admitted | C.turned | D.moved |
What I need is_____ book that contains ______ABC of oil painting.
A.a; 不填 | B.the; 不填 | C.the; an | D.a ; the |
Jenny nearly missed the flight______ doing too much shopping.
A.as a result of | B.on top of | C.in front of | D.in need of |
The CDs are on sale! Buy one and you get ______ completely free.
A. | other | B. | others | C. | one | D. | ones |