题干

.某研究性学习小组为了探究镁粉与溴水反应的机理,做了如下四种实验:①将镁粉投入到冷水中,未观察到明显现象;②将镁粉投入到溴水中,观察到只是开始时产生极少量的气泡,但溴水会慢慢退色;③将镁粉投入到液溴中,未观察到明显现象;④向含有足量镁粉的液溴中滴加几滴水,观察到溴的红棕色很快退去。下列关于镁粉与溴水的反应机理的叙述中正确的是

A:镁粉只直接与溴水中的溴反应

B:镁粉只与溴水中的酸反应

C:产生极少量的气泡是由于镁粉与水反应得到的

D:镁粉在水的催化下与溴发生反应

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D

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    The technique can lead to new ways to produce medicines, the researchers from the universities of Istanbul and Hawaii hope.

    As part of an effort to improve treatments for life-threatening illnesses, a team of scientists have created rabbits that glow(发光) in the dark.

    Their efforts produced two rabbits out of a litter of eight that went from being a normal, fluffy white to glowing green in the dark. The rabbits were born at the University of Istanbul as part of a collaboration(合作) between scientists from universities in Turkey and Hawaii.

    The rabbits glow to show that a genetic manipulation technique can work efficiently, though the specific color is more cosmetic than scientific. "The green is not important at all – it's just a marker to show the experiment can be done successfully," said University of Hawaii associate professor Stefan Moisyadi.

    To produce the glowing effect, researchers injected jellyfish DNA into a mother rabbit's embryos. Those altered embryos(胚胎). Those altered embryos were then inserted back into the mother. Similar experiments have resulted in glowing cockroaches and cats.

    Eventually, the researchers hope the technique can lead to new ways to produce medicines, Moisyadi said. “The final goal is to develop animals that act as barrier reactive to produce beneficial molecules in their milk that can be cheaply extracted, especially in countries that can't afford big pharma plants that make drugs, that usually cost $1bn to build, and be able to produce their own protein-based medication in animals," Moisyadi said.

    The rabbits are expected to have the same life span as their non-glowing counterparts(副本), but Moisyadi said he understands people can object to this kind of experimentation involving live animals.

    "To the people against, I say: think about, what are the benefits and what are the injuries?" Moisyadi said. "And if the benefits outweigh the injuries, let's go with the benefits."

    Moisyadi, a native of Turkey who is now with the University of Hawaii, started developing the project in 2006, and researchers are now waiting to see if pregnant sheep produce similar results.