问题 判断题

焊接不锈钢及耐热钢的溶剂牌号是气剂201。

答案

参考答案:

单项选择题

阅读下面短文,回答以下问题。
海豚是怎样发出声呐信号的这个问题长期以来一直困扰着科学家。生物学家克兰弗德和物理学家阿罗安经过共同努力,用一个新奇的计算机模拟系统得出一个比较确实的答案。阿罗安说:“以前没有人尝试过模拟声音在海豚肌体组织个的传播,我们开辟了一个崭新领域:模拟生物声学。”
为什么海豚声呐问题长期无人解出阿罗安说:“以前的研究没有结果是因为科学家们在研究时,从真海豚身上一块我们称之为近区一因为这部位离声源很近一的部位着手。他们听到了繁杂的信号和许多干扰,而要想再将声源还原到海豚头像上找出声源就十分困难了,而我们的电脑模拟图像是解决这个问题的最佳工具。”
他继续解释:“主要的问题是,海豚怎样发出脉冲和脉冲怎样集成定向波”阿罗安和克兰弗德的模拟图像把这两个问题都解答出来了。“我们发观了有力的证据证明声波的源头在海豚鼻孔上两三厘米处。这个地方克兰弗德称之为MLDB——猴唇形背囊——它就在海豚出气孔下面的第一个大气囊的正下方。”
海豚呼吸时,空气由出气孔进入鼻孔。当空气离开呼吸系统时,喉部的压力使一小部分气体上升,挤入鼻孔顶部附近的唇形部位(猴唇)。当气体通过这两片“唇”时,两片“唇”就发生颤动。两片“唇”拍击,就产生了脉冲。海豚将空气贮存在两片“唇”上部的一个气囊里,然后将这部分气体循环使用,反复这个过程。这样,当海豚要发出一系列脉冲声,就不用每次都再回到水面上吸气。
阿罗安说:“当这两片唇闭合时,声波就被震入海豚的肌体组织,震入鼻疣(前额凸起部位),然后直接进入水里。”
(佚名《海豚与声呐》)

文中“这个问题”是指:

A.海豚声呐的问题。

B.排除繁杂的信号和干扰。

C.找出海豚发声的声源。

D.将声源还原到海豚头像上。

单项选择题

Fate has not been kind to the western grey whale. Its numbers have dwindled to 130 or so, leaving it “critically endangered” in the eyes of the International Union for the Conservation of Nature. Fishing-nets, speeding ships, pollution and coastal development threaten the few that remain. Most recently, drilling for oil and gas in their main summer feeding grounds, near Sakhalin island off Russia’s Pacific coast, has brought fresh risks for the luckless creatures. Yet the rush to develop Sakhalin’s offshore fields may yet be the saviour of the species.

When drilling was first discussed in the 1990s, there were muted complaints. When a consortium called Sakhalin. Energy, led by Royal Dutch Shell, announced plans to build an oil platform and lay pipelines in the only bay where the whales were known to congregate, these protests proliferated.

In response, the consortium established an independent panel to advise it on how best to protect the whales and promised to fund its work. It subsequently agreed to change the route of the pipeline at the panel’s suggestion, although it refused to move the platform, as other critics had demanded. It also agreed either to follow the panel’s recommendations in future or to explain publicly why it was rejecting them.

The platforms and pipelines are now complete. Sakhalin Energy exported its first cargo of liquefied natural gas last week. The project, says Shell, is an engineering triumph and a commercial success despite all the controversy.

But has it been a success for the whales Sakhalin Energy says their number seems to be growing by 2.5% a year, although Ian Craig, the firm’s boss, admits that the cause might be greater scrutiny rather than population growth. The scientists on the panel still seem worried. They complain that the firm has not always provided the information they need to assess the threat to the whales. It also has not always followed advice, the scientists’ advice about how noisy construction might scare the animals away, for example, or the speed that boats should travel to minimize the risk of hitting the whales. The scientists warn that the loss of just a few fertile females would be enough to tip the population into irrevocable decline. Last summer, there seemed to be far fewer whales around than normal.

On the other hand, the panel knows this only because Sakhalin Energy funds lots of research on the whales. As a result, it has discovered that they have a wider range than originally thought, which might explain why so few of them showed up off Sakhalin island last year.

Therefore, it is hard to escape the conclusion that, for creatures with a lot as sorry as the western grey whale, a nearby oil project is something of a blessing.

Sakhalin Energy supports the panel’s work()

A. unconditionally

B. enthusiastically

C. half heartedly

D. earnestly