| Scraps of food could soon be helping
power your home, thanks to an ultra-cheap bacteria-driven battery. Its
developers hope that instead of feeding the dog or making garden compost(混合肥料)
,organic household waste could top up your home’s electricity. Although such "microbial fuel cells" (MFCs)have been developed in the past, they have always proved extremely inefficient and expensive. Now Chris Melhuish and technologists at the University of the West of England(UWE)in Bristol have come up with a simplified MFC that costs as little as ￡10 to make. Right now, their fuel cell runs only on sugar cubes, since these produce almost no waste when broken down, but they aim to move on to carrot power. "It has to be able to use raw materials, rather than giving it a refined fuel," says Melhuish. Inside the Walkman-sized battery, A. The MFC is not a kind of new-developed fuel. B. The MFC was not spread used in the past partly because of its high cost. C. The MFC was proved to be able to power domestic appliance. D. The previous MFC can produce eight times as much power as the current organic battery. [判断题]四显示自动闭塞区段,通过信号机显示一个绿色灯光——准许列车按规定速度运行,表示运行前方至少有二个闭塞分区空闲。( )
A.正确 B.错误 [不定项选择题]共用题干
The Drink Your Body Needs Most
1 Our bodies are estimated to be about 60% to 70% water.Blood is mostly water,and our muscles,lungs,and brain all contain a lot of water.Water is needed to regulate body temperature and to provide the means for nutrients（滋养物）to travel to all our organs. Water also transports oxygen to our cells,removes waste,and protects our joints and organs. 2 We lose water through urination（排尿）,respiration（呼吸）,and by sweating. If you are very active,you lose more water than if you do not take much exercise.Symptoms of mild dehydration（脱水）include chronic pains in joints and muscles , lower back pain, headaches, and constipation（便秘）.A strong smell to your urine , along with a yellow color indicates that you are not getting enough water.Thirst is an obvious sign of dehydration and in fact,you need water long before you feel thirsty. 3 A good rule of thumb（好的做法）is to take your body weight in pounds and divide that number in half. That gives you the number of ounces（盎司）of water per day that you need.For example,if you weigh 160 pounds,you should drink at least 80 ounces of water per day.If you exercise you should drink another 8-ounce glass of water for every 20 minutes you are active.If you drink coffee or alcohol,you should add at least an equal amount of water.When you are traveling on an airpiane,it is good to have 8 ounces of water for every hour you are on board the plane. 4 It may be difficult to drink enough water on a busy day.Be sure you have water handy at all times by keeping a bottle for water with you when you are working,traveling,or exercising.If you get bored with plain water,add a bit of lemon for a touch of flavor.There are some brands of flavored water available,but some of them have sugar or artificial sweeteners that you don't need. The amount of water your body needs per day is closely related________. A.in your body B.without water C.before long D.for a change E.on a busy day F.to your weight [多选题]对服务质量问题的处罚,坚持( )的原则。
A.实事求是 B.惩前毖后 C.治病救人 D.依法依规 [单选题]电力系统发生接地故障时产生的零序分量相当于（）。
A.3n次（其中n为正整数 B.3n+1次（其中n为正整数 C.3n-1次（其中n为正整数） D.上述三种以外 [单选题]消防救援队伍领导干部经济责任审计按照（ ）等次，对领导干部履行经济责任情况确定评价结果。
A.好、较好、一般、差 B.优秀、良好、合格、差 C.优秀、称职、不称职 D.优秀、良好、不称职 我来回答: 提交
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