题型:阅读选择 题类: 难易度:普通
湖南省长沙市雅礼中学2024届炎德英才联考英语模拟试卷二(音频暂未更新)
Scientists have made a "breakthrough" in handling nuclear fusion(核聚变). The US Department of Energy officially announced the milestone in fusion energy research.
For the first time, researchers created a nuclear fusion reaction that produced more energy than they put into the process. The experiment, conducted at Lawrence Livermore National Laboratory in California, generated 3.15 megajoules of energy, more than the 2.05 megajoules put into creating it.
Nuclear fusion works by forcing together two atoms—most often hydrogen—to make a heavier one—like helium(氦). This explosive process releases massive amounts of energy, the Department of Energy explains. Fusion is the opposite of fission(裂变), the reaction that powers nuclear reactors used commercially today.
Fusion occurs naturally in the heart of the Sun and the stars, providing these cosmic(宇宙的) objects with fuel. Since the 1950s, scientists have been trying to reproduce it on Earth inorder to make use of the so-called clean, cheap, and almost limitless electricity. According to the International Atomic Energy Agency, fusion generates four times more energy per kilogram than the fission used to power nuclear plants, and nearly 4 million times more energy than burning oil or coal. What's more, unlike fossil fuels, fusion doesn't release carbon dioxide—the greenhouse gas that's the main driver of climate change — into the atmosphere. And unlike nuclear fission, fusion doesn't create long-lived radioactive waste, according to the Department of Energy. But so far, nuclear fusion hasn't solved our energy problems on a grand scale.
The recent announcement is a huge step forward in nuclear fusion energy, but applying the technology at commercial scale is likely still years away. Chanda Prescod Weinstein, a theoretical physicist, pointed out that the process the Department of Energy uses requires tritium(氚), a rare and radioactive isotope(同位素) of hydrogen."It may yet convey important information that is ultimately transformative. We don't know yet,"Prescod Weinstein tweeted. Investors, including Amazon founder Jeff Bezos, have poured billions into the clean energy field trying to make fusion commercially workable, and the recent announcement is likely to continue that trend.
Recently, a primary school in Jiangsu, brought out a new policy(政策) about homework. Students should stop doing homework at 9 pm, even if they haven't finished all of it. They don't need to make it up the next day. This is to make sure that students have enough sleep time. Do you think it's a good idea?
Yes Kids should get about 10 hours of sleep every day. The best time to sleep is between 9:00pm to 9:30 pm. This is because we kids are at the peak(高峰期) of our physical growth. The time between 10 pm to 1 am is especially important for our growth. At the same time, not having enough sleep will make us feel tired. For example, once I slept late, I would feel sleepy and upset the next morning. Yu Haozhe,15 |
No Even if we don't study after 9 pm, many teenagers will not go to bed. They may play games or watch TV. Also, finishing homework is our main task as students. If you don't do homework, how can you improve yourself? So I want to say that our study should not be limited by time. We should improve our study efficiency(效率)according to our own situation. Lin Sinuo,15 |
A. looks like B. near C. because D. spaceship E. costs F. light G. takes |
The moon is our nearest neighbour in space. It is the earth's satellite (卫星) and men have visited it already. It is smaller than the earth. Plants can't grow on the moon {#blank#}1{#/blank#} there is no air or water on it.
The moon doesn't have its own light. It shines back the {#blank#}2{#/blank#} of the sun. When the sun is shining on the side of the moon which faces us, it {#blank#}3{#/blank#} a great ball. We can't see the other side of the moon, because that side never faces the earth.
In fact, the moon isn't as {#blank#}4{#/blank#} as it looks. It is three hundred and eighty thousand kilometres away from the earth. Of course, we can fly to the moon in a {#blank#}5{#/blank#}. A spaceship flies very, very fast, and it flies at about eleven kilometres a second, so it only {#blank#}6{#/blank#} more than three days to get there by spaceship.
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