更多"A nuclear reactor is protected by _"的相关试题:
[填空题]The first nuclear reactor to provide electricity to a national grid opened in England in ______.
[填空题]Control rods in a nuclear reactor are used to control the amount of energy generated in a nuclear reactor. They can also be used to shut the reactor or to change the fuel.
[填空题]Uranium has to be enriched if a nuclear reactor is built.
[简答题]Nuclear proliferation
[填空题]Nuclear technology was sold by a Pakistani nuclear scientist to Libya, North Korea and Pakistan.
[单项选择]The nuclear polyhedrosis virus helps control gypsy moth populations by killing the moth’s larvae. The virus is always present in the larvae, but only every sixth or seventh year does the virus seriously decimate the number of larvae, thereby drastically setting back the gypsy moth population. Scientists believe that the virus, ordinarily latent, is triggered only when the larvae experience biological stress.
If the scientists mentioned above are correct, it can be inferred that the decimation of gypsy moth larvae populations by the nuclear polyhedrosis virus would be most likely to be triggered by which of the following conditions
A. A shift from drought conditions to normal precipitation in areas infested by gypsy moths.
B. The escalating stress of defoliation sustained by trees at tacked by gypsy moths for the second consecutive year.
C. Predation on larvae of all kinds by parasitic wasps and flies.
D. Starvation of the gypsy moth larvae as a result of overpopulation.
E. (E) Spraying of areas infested by gypsy moths with laboratory-raised nuclear polyhedrosis virus.
[填空题]Under no circumstances will we use nuclear weapons first.
[单项选择]Nuclear weapons were first developed in the United States during the Second World War, to be used against Germany. However, by the time the first bombs were ready for use, the war with Germany had ended and, as a result, the decision was made to use the weapons against Japan instead. Hiroshima and Nagasaki have suffered the consequences of this decision to the present day.
The real reasons why bombs were dropped on two heavily-populated cities are not altogether clear. A number of people in 1944 and early 1945 argued that the use of nuclear weapons would be unnecessary, since American Intelligence was aware that some of the most powerful and influential people in Japan had already realized that the war was lost, and wanted to negotiate a Japanese surrender. It was also argued that, since Japan has few natural resources, a blockade by the American navy would force it to surrender within a few weeks, and the use of nuclear weapons would thus prove unnecessary. If a demonstration of
A. puzzled.
B. critical.
C. supportive.
D. objective.