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某C20混凝土施工配合比为：水：139kg/m3水泥：385kg/m3砂：588kg/m3石：1328kg/m3拟省去水泥配零工作量，根据每罐配三袋水泥（150kg）计，相应地用水量和骨料用量是多少?
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Japanese Car Keeps Watch for Drunk Drivers A concept car developed by Japanese company Nissan has a breathalyzer-like detection system and other instruments that could help keep drunk or over tired drivers off the road. The car’s sensors check odors inside the car and monitor a driver’s sweat for traces of alcohol. An in-car computer system can issue an alert or even lock up the ignition system if the driver seems over-the-limit. The air odor sensors are fixed firmly and deeply in the driver and passenger seats, while a detector in the gear-shift knob measures perspiration from the driver’s palm. Other carmakers have developed similar detection systems. For example, Sweden’s Volvo has developed a breathalyzer attached to a car’s seat belt that drivers must blow into before the engine will start. Nissan’s new concept vehicle also includes a dashboard-mounted camera that tracks a drivers alertness by monitoring their eyes. It will sound an alarm and issue a spoken warning in Japanese or English if it judges that the driver needs to pull over and rest. The car technology is still in development, but general manager Kazuhiro Doi says the combination of different detection systems should improve the overall effectiveness of the technology. "For example, if the gear-shift sensor was bypassed by a passenger using it instead of the driver, the facial recognition system would still be used," Doi says. Nissan has no specific timetable for marketing the system, but aims to use technology to cut the number of fatalities involving its vehicles to half 1995 levels by 2015. The car’s seat belt can also tighten if drowsiness is detected, while an external camera checks that the car is keeping to its lane properly. However, Doi admits that some of the technology, such as the alcohol odor sensor, should be improved. "If you drink one beer, it’s going to register, so we need to study what’s the appropriate level for the system to activate," he says. In the UK, some research groups are using similar advanced techniques to understand driver behavior and the effectiveness of different road designs. Which of the following statements is NOT true of the Japanese concept care
A Sunshade for the Planet Even with the best will in the world, reducing our carbon emissions is not going to prevent global wanning. It has become clear that even if we take the strongest measures to control emissions, the uncertainties in our climate models still leave open the possibility of extreme warming and rises in sea level. At the same time, resistance by governments and special interest groups makes it quite possible that the actions suggested by climate scientists might not be implemented soon enough. Fortunately, if the worst comes to the worst, scientists still have a few tricks up their sleeves. For the most part they have strongly resisted discussing these options for fear of inviting a sense of complacency that might thwart efforts to tackle the root of the problem. Until now, that is, a growing number of researchers are taking a fresh look at large-scale "geo-engineering" projects that might be used to counteract global wanning. "I use the analogy of methadone," says Stephen Schneider, a climate researcher at Stanford University in California who was among the first to draw attention to global warming. "If you have a heroin addict, the correct treatment is hospitalization and a long rehab. But if they absolutely refuse, methadone is better than heroin. " Basically the idea is to apply "sunscreen" to the whole planet. One astronomer has come up with a radical plan to cool Earth; launch trillions of feather-light discs into space, where they would form a vast cloud that would block the sun’s rays. It’s controversial, but recent studies suggest there are ways to deflect just enough of the sunlight reaching the Earth’s surface to counteract the warming produced by the greenhouse effect. Global climate models show that blocking just 1.8 per cent of the incident energy in the sun’s rays would cancel out the warming effects produced by a doubling of greenhouse gases in the atmosphere. That could be crucial, because even the most severe emissions-control measures being proposed would leave us with a doubling of carbon dioxide by the end of this century, and that would last for at least a century more. What does Stephen Schneider say about a heroin addict and methadone
Sport or Spectacle Muhammad Ali is probably the most famous sports figure on earth: he is recognized on every continent and by all generations. The diagnosis of his illness (51) Parlonson’s disease after his retirement fuelled the debate about the dangers of boxing and criticism (52) the sport. That, plus his outspoken opposition (53) women’s boxing, made people wonder how he would react when one of his daughters decided to take (54) the sport. His presence at Laila’s first professional fight, (55) _, seemed to broadcast her father’s support. Of course Muhammnad Ali wanted to watch his daughter fight. The ring announcer introduced him as the "the greatest" and as he sat down at the ringside the crowd chanted. Twenty-one-year-old Laila’s debut fight was a huge success and there was as much publicity for the fight (56) her father’s fights once attracted. (57) , Laila’s opponent was much weaker than she was and the fight lasted just 31 seconds. Since then, Laila has won most of her fights by knocking out her opponent. "She knows (58) she’s doing, all fight, "said one referee about her. "She knows about moving well. You can see some of her dad’s moves." Laila Ali would rather not compare herself (59) her father. She prefers to make her own (60) . Her father supports her decision to enter the sport but he has not spared her the details of what can happen. Laila realizes that her father wants her to understand the (61) possible scenario to see (62) she still wants to go forward with it. She knows she’s going to get hit hard at times, that she may get a broken nose or a swollen face, but at least she is prepared for it. Laila’s decision to start boxing (63) her father’s struggle with the symptoms of Parkinson’s disease has of course sparked a mixture of debate and (64) . But Laila is a feisty and determined individual and it is that as much as her famous last name that has made her a magnet for worldwide media attention. Of course, the (65) on the boxing scene of a woman with her family history attracts even more questions about whether women’s boxing is sport or spectacle．
A Sunshade for the Planet Even with the best will in the world, reducing our carbon emissions is not going to prevent global wanning. It has become clear that even if we take the strongest measures to control emissions, the uncertainties in our climate models still leave open the possibility of extreme warming and rises in sea level. At the same time, resistance by governments and special interest groups makes it quite possible that the actions suggested by climate scientists might not be implemented soon enough. Fortunately, if the worst comes to the worst, scientists still have a few tricks up their sleeves. For the most part they have strongly resisted discussing these options for fear of inviting a sense of complacency that might thwart efforts to tackle the root of the problem. Until now, that is, a growing number of researchers are taking a fresh look at large-scale "geo-engineering" projects that might be used to counteract global wanning. "I use the analogy of methadone," says Stephen Schneider, a climate researcher at Stanford University in California who was among the first to draw attention to global warming. "If you have a heroin addict, the correct treatment is hospitalization and a long rehab. But if they absolutely refuse, methadone is better than heroin. " Basically the idea is to apply "sunscreen" to the whole planet. One astronomer has come up with a radical plan to cool Earth; launch trillions of feather-light discs into space, where they would form a vast cloud that would block the sun’s rays. It’s controversial, but recent studies suggest there are ways to deflect just enough of the sunlight reaching the Earth’s surface to counteract the warming produced by the greenhouse effect. Global climate models show that blocking just 1.8 per cent of the incident energy in the sun’s rays would cancel out the warming effects produced by a doubling of greenhouse gases in the atmosphere. That could be crucial, because even the most severe emissions-control measures being proposed would leave us with a doubling of carbon dioxide by the end of this century, and that would last for at least a century more. Scientists resist talking about their options because they don’t want people to______.
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