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Advances in scientific understanding often do not
build directly or smoothly in response to the data that
are amassed , and in retrospect , after a major revision
of theory , it may seem strange that a crucial hypothesis
( 5 ) was long overlooked . A case in point is the discovery
of a means by which the nuclei of atoms can be split .
Between 1934 , when a group of Italian physicists
including Enrico Fermi first bombarded uranium with
neutrons , and 1939 , when exiled Austrian physicist
(10 ) Lise Meitner provided the crucial theoretical
connection , scientists compiled increasing evidence
that nuclear fission had been achieved . without
however , recognizing what they were witnessing
Earlier , even before the neutron and proton
(15 ) composition of atomic nuclei had been experimentally
demonstrated , some theoretical physicists had
produced calculations indicating that in principle it
should be possible to break atoms apart . But the
neutron-bombardment experiments were not aimed at
( 20 ) achsieving such a result , and researchers were not even
receptive to the possibility that it might happen in that
context . A common view was that a neutron’s breaking
apart a uranium nucleus would be analogous to a
pebble , thrown through a window , causing a house
( 25 ) to collapse
In Berlin , Meitner pursued research related to that
of the Italians , discovering a puzzling group of
radioactive substances produced by neutron
jbombardment of uranium . Fermi and others achieved
( 30 ) numerous similar results . These products remained
unidentified partly because precise chemical analyses
were hampered by the minute quantities of the
substances produced and the dangers of working with
highly radioactive matterials , but more significantly
( 35 ) because of the expectation that they would all be
elements close to uranium in nuclear composition.
In 1938 Meitner escaped from Nazi Germany and
undertook related research in Sweden , but her research
partner Otto Hahn kept her informed of his continuing
( 40 ) experimentation . Late in that year he wrote to her of a
surprising result : one of the substances resulting from
the neutron bombardment of uranium had been
conclusively identified as barium , an element whose
structure would have made it impossible to produce
( 45 ) through any mechanism he envisaged as being
involved in the experiments . Hahn even remarked
that , despite the clear chemical evidence of what had
occurred , it went against all previous experiences of
nuclear physics , but he also noted that together the
( 50 ) number of protons and neutrons in the nuclei of
barium and technetium , the accompanying product
of the experiment , added up to the number of such
particles that compose a uranium nucleus
It was Meitner who finally recognized the
( 55 ) significance of the data in relation to underlying
theoretical considerations : the researchers had actually
been splitting uranium atoms . Coining the term
“nuclear fission , she quickly submitted her
conclusion for publication in a paper coauthored with
( 60 ) physicist Otto Frisch . When scientists in Europe and
North America rushed to corroborate the findings .
it became clear that the relevant evidence had been
present for some time , lacking mainly the right
conceptual link .
Given the information in the passage , which one of the following , if true , would have been most likely reduce the amount of time it took for physicists to realize that atoms were being split ?
答案:B

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Reading Comprehension

老师E感觉也对呀,用uranium一直出不来,说不定换种别的就出来了

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