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二十四节气中只有___________，既是节气又是节日，是踏青的好时候。 There is only___________in 24 solar terms, It's not only a solar term but also a festival. It's a good time for outing.
参考答案和解析
清明;冬至
更多 “二十四节气中只有___________，既是节气又是节日，是踏青的好时候。 There is only___________in 24 solar terms, It's not only a solar term but also a festival. It's a good time for outing.” 相关考题
考题
When people speak of solar energy, they only think of sun’s rays heating a home or ________ electricity from the sun.
A.deriveB.to deriveC.derivingD.of deriving.
考题
A mean sun is used as the reference for solar time for three reasons. Which reason is NOT a cause for use of a mean sun?A.The motion of the apparent sun is along the eclipticB.Measurement of time is along the celestial equatorC.The speed of the Earth's revolution is not constantD.There are variations in the Earth's rotational speed
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Better Solar Energy Systems:More Heat,More LightSolar photovoltaic（光电的）thermal energy systems , or PVTs , generate both heat and electricity , but _________ (51)now they haven't been very good at the heat-generating part compared to a stand-alone solar thermal collector. That ' s because they operate at low temperatures to cool crystalline silicon（晶体硅）solar cells, _______(52)lets the silicon generate more electricity but isn't a very efficient way to gather heat.That's a problem of economics.Good solar hot-water systems can harvest much more energy than asolar一electric system at a substantially lower _________(53).And it's also a space problem:photovoltaiccells can_________(54)up all the space on the roof,leaving little room for thermal applications.In a pair of studies,Joshua Pearce,an associate professor of materials science and engineering,has de- vised a_________(55)in the form of a better PVT made with a different kind of silicon.Most solar panels are made with crystalline silicon,but you can also make solar cells out of amorphous（非晶形的）silicon , commonly known________( 56 ) thin-film silicon. They don ' t create as much elec-tricity,but they are lighter,flexible,and cheaper. And,because they________(57)much less silicon,they have a greener footprint._________(58),thin-film silicon solar cells are vulnerable to some bad一news physics in the form of the Staebler-Wronski effect."That means that their efficiency drops when you_________(59)them to light一pretty much the worst possible effect for a solar cell,"Pearce explains,which is one of the__________(60)thin-film solar panels make up only a small fraction of the market.However,Pearce and his team found a_______(61)to engineer around the Staebler-Wronski effect by incorporating thin-film silicon in a new________(62)of PVT. You don't have to cool down thin-film sili- con to make it work.In fact,Pearce's group discovered that by heating it to solar-thermal operating tempera- tures,near the boiling_________(63)of water,they could make thicker cells that largely_________(64) the Staebler-Wronski effect.When they applied the thin-film silicon directly to a solar thermal energy collector, they also found that by baking the cell once a day,they_________(65)the solar cell's electrical efficiency by over 10 percent._________(57)A:retrieveB:requireC:mergeD:exchange
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Solar StormAt the end of October 2003,a sudden solar storm hit the earth.A solar storm refers to the large amounts of charged particles released into space_________(1)the solar energyincreases.The release of the energy_________(2)place along with the activity of the sunspots with a cycle of 11 years.This time,the_________(3)of the storm exceeded expectations.This_________(4)of intense solar storm was caused by the eruption of a solar flare （闪光）and the ejection（喷发）of the solar corona（日冠）on October28, 2003. Large amounts of charged particles moved 150, 000,000 kilometers through space toward the _________(5)in 19 hours. They could affect aircraft roaming（漫游）in space.The high-energy particles will_________(6)some of the parts of an aircraft.They may also cause it to fail.High-energy particles can threaten the safety of an aircraft at a high orbit.If an aircraft orbits at a lower orbit,it is_________(7)because it is under the protection of the earth's magnetic field.A solar storm not only affects aircraft but also is a_________(8)to the environment and humans.The aerosphere and magnetic field of the earth can_________(9)humans from ultraviolet radiation and X-rays. While most of the X-rays are absorbed after they enter the aerosphere（大气层）,still a few can_________(10) the ground.The geomagnetic storm caused by this round of solar storm reaches its highest level on the two_________(11)of the earth,which affects electricity supply of North America. Overexposure to_________(12)threatens the health of passengers on planes flying over the Polar Regions.If we fly in the sky during such a solar storm,it_________(13)we receive ten times the X-ray radiation.It's really damaging.Scientists say a solar eruption is like the sun sneezing,which will make the earth _________(14)a cold.Though this natural force is irresistible,scientists can still _________(15)its movement accurately by monitoring.Facing successive solar storms, humans can't drop their guard._________(13)A:recommends B:means C:proposes D:advises
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Better Solar Energy Systems: More Heat, More LightSolar photovoltaic thermal energy systems,or PVTs,generate both heat and electricity,but until now they haven't been very good at the heat-generating part compared to a stand-alone solar thermal collector. That's because they operate at low temperatures to cool crystalline silicon solar cells,which lets the silicon generate more electricity but isn't a very efficient way to gather heat.That's a problem of economics. Good solar hot-water systems can harvest much more energy than a solar-electric system at a substantially lower cost. And it's also a space problem:photovol-taic cells can take up all the space on the roof,leaving little room for thermal applications.In a pair of studies,Joshua Pearce,an associate professor of materials science and engineer-ing,has devised a solution in the form of a better PVT made with a different kind of silicon.His research collaborators are Kunal Girotra from Thin Silicon in California and Michael Pathak and Stephen Harrison from Queen's University,Canada.Most solar panels are made with crystalline silicon,but you can also make solar cells out of amorphous silicon,commonly known as thin-film silicon.They don't create as much electricity, but they are lighter,flexible,and cheaper. And,because they require much less silicon,they have a greener footprint. Unfortunately,thin-film silicon solar cells are vulnerable to some bad-news physics in the form of the Staebler-Wronski effect."That means that their efficiency drops when you expose them to light-pretty much the worst possible effect for a solar cell,"Pearce explains,which is one of the reasons thin-film solar panels make up only a small fraction of the market.However,Pearce and his team found a way to engineer around the Staebler-Wronski effect by incorporating thin-film silicon in a new type of PVT. You don't have to cool down thin-film silicon to make it work.In fact,Pearce's group discovered that by heating it to solar-thermal operating temperatures,near the boiling point of water,they could make thicker cells that largely overcame the Staebler-Wronski effect. When they applied the thin-fulm silicon directly to a solar thermal en-ergy collector,they also found that by baking the cell once a day,they boosted the solar cell's e-lectrical efficiency by over 10 percent. One of the problems PVTs have is that______.A: their thermal applications are costlyB: they are too expensive to affordC: they occupy too much spaceD: it is hard to fix them on the roof
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California Gives Green Light to Space Solar PowerEnergy beamed down from space is one step closer to reality,now that California has given the green light to an agreement that would see the Pacific Gas and Electric Company buy 200 megawatts（兆瓦）of power beamed down from solar-power satellites beginning in 2016.But some major challenges will have to beovercome if the technology is to be used widely.A start-up company called Solaren is designing the satellites,which it says will use radio waves to beamenergy down to a receiving station on Earth.The attraction of collecting solar power in space is the almost uninterrupted sunshine available in geo- synchronous（与地球同步的）orbit. Earth-based solar cells , by contrast , can only collect sun light during day-time and when skies are clear.But space-based solar power must grapple（努力克服）with the high cost per kilogram of launching things in- to space,says Richard Schwartz of Purdue University in West Lafayette,Indiana."if you're talking about it being economically viable for power of the Earth,it's a tough go,"he says.Cal Boerman,Solaren's director of energy services,says the company designed its satellites with a view to keeping launch costs down."We knew we had to come up with a different,revolutionary design,"he says. A patent the company has won describes ways to reduce the system's weight,including using inflatable mir- rors to focus sunlight on solar cells,so a smaller number can collect the same amount of energy.But using mirrors introduces other challenges,including keeping the solar cells from overheating,says Schwartz."You have to take care of heat dissipation（散发）because you're now concentrating a lot of energy in one place,"he says.According to the company's patent,Solaren's solar cells will be connected to radia-tors to help keep them cool.Though Boerman says the company believes it can make space-based solar power work,it is not expec-ting to crowd out other forms of renewable energy.Laws in California and other states require increasing use of renewable energy in coming years,he points out."To meet those needs,we're going to need all types of renewable energy sources,"he says.Solaren is going to design 200 solar-power satellites.A:RightB:WrongC:Not mentioned
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Better Solar Energy Systems: More Heat, More LightSolar photovoltaic thermal energy systems,or PVTs,generate both heat and electricity,but until now they haven't been very good at the heat-generating part compared to a stand-alone solar thermal collector. That's because they operate at low temperatures to cool crystalline silicon solar cells,which lets the silicon generate more electricity but isn't a very efficient way to gather heat.That's a problem of economics. Good solar hot-water systems can harvest much more energy than a solar-electric system at a substantially lower cost. And it's also a space problem:photovol-taic cells can take up all the space on the roof,leaving little room for thermal applications.In a pair of studies,Joshua Pearce,an associate professor of materials science and engineer-ing,has devised a solution in the form of a better PVT made with a different kind of silicon.His research collaborators are Kunal Girotra from Thin Silicon in California and Michael Pathak and Stephen Harrison from Queen's University,Canada.Most solar panels are made with crystalline silicon,but you can also make solar cells out of amorphous silicon,commonly known as thin-film silicon.They don't create as much electricity, but they are lighter,flexible,and cheaper. And,because they require much less silicon,they have a greener footprint. Unfortunately,thin-film silicon solar cells are vulnerable to some bad-news physics in the form of the Staebler-Wronski effect."That means that their efficiency drops when you expose them to light-pretty much the worst possible effect for a solar cell,"Pearce explains,which is one of the reasons thin-film solar panels make up only a small fraction of the market.However,Pearce and his team found a way to engineer around the Staebler-Wronski effect by incorporating thin-film silicon in a new type of PVT. You don't have to cool down thin-film silicon to make it work.In fact,Pearce's group discovered that by heating it to solar-thermal operating temperatures,near the boiling point of water,they could make thicker cells that largely overcame the Staebler-Wronski effect. When they applied the thin-fulm silicon directly to a solar thermal en-ergy collector,they also found that by baking the cell once a day,they boosted the solar cell's e-lectrical efficiency by over 10 percent. Which of the following is NOT mentioned as an advantage of thin-film silicon solar cells?A:.They are electrically efficient.B: They are less expensive.C:.They are flexible.D: They are environment friendly.
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Better Solar Energy Systems: More Heat, More LightSolar photovoltaic thermal energy systems,or PVTs,generate both heat and electricity,but until now they haven't been very good at the heat-generating part compared to a stand-alone solar thermal collector. That's because they operate at low temperatures to cool crystalline silicon solar cells,which lets the silicon generate more electricity but isn't a very efficient way to gather heat.That's a problem of economics. Good solar hot-water systems can harvest much more energy than a solar-electric system at a substantially lower cost. And it's also a space problem:photovol-taic cells can take up all the space on the roof,leaving little room for thermal applications.In a pair of studies,Joshua Pearce,an associate professor of materials science and engineer-ing,has devised a solution in the form of a better PVT made with a different kind of silicon.His research collaborators are Kunal Girotra from Thin Silicon in California and Michael Pathak and Stephen Harrison from Queen's University,Canada.Most solar panels are made with crystalline silicon,but you can also make solar cells out of amorphous silicon,commonly known as thin-film silicon.They don't create as much electricity, but they are lighter,flexible,and cheaper. And,because they require much less silicon,they have a greener footprint. Unfortunately,thin-film silicon solar cells are vulnerable to some bad-news physics in the form of the Staebler-Wronski effect."That means that their efficiency drops when you expose them to light-pretty much the worst possible effect for a solar cell,"Pearce explains,which is one of the reasons thin-film solar panels make up only a small fraction of the market.However,Pearce and his team found a way to engineer around the Staebler-Wronski effect by incorporating thin-film silicon in a new type of PVT. You don't have to cool down thin-film silicon to make it work.In fact,Pearce's group discovered that by heating it to solar-thermal operating temperatures,near the boiling point of water,they could make thicker cells that largely overcame the Staebler-Wronski effect. When they applied the thin-fulm silicon directly to a solar thermal en-ergy collector,they also found that by baking the cell once a day,they boosted the solar cell's e-lectrical efficiency by over 10 percent. PVTs are not efficient in______.A:.creating electricityB: cooling silicon solar cellsC: generating heatD: powering solar thermal collectors
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Better Solar Energy Systems: More Heat, More LightSolar photovoltaic thermal energy systems,or PVTs,generate both heat and electricity,but until now they haven't been very good at the heat-generating part compared to a stand-alone solar thermal collector. That's because they operate at low temperatures to cool crystalline silicon solar cells,which lets the silicon generate more electricity but isn't a very efficient way to gather heat.That's a problem of economics. Good solar hot-water systems can harvest much more energy than a solar-electric system at a substantially lower cost. And it's also a space problem:photovol-taic cells can take up all the space on the roof,leaving little room for thermal applications.In a pair of studies,Joshua Pearce,an associate professor of materials science and engineer-ing,has devised a solution in the form of a better PVT made with a different kind of silicon.His research collaborators are Kunal Girotra from Thin Silicon in California and Michael Pathak and Stephen Harrison from Queen's University,Canada.Most solar panels are made with crystalline silicon,but you can also make solar cells out of amorphous silicon,commonly known as thin-film silicon.They don't create as much electricity, but they are lighter,flexible,and cheaper. And,because they require much less silicon,they have a greener footprint. Unfortunately,thin-film silicon solar cells are vulnerable to some bad-news physics in the form of the Staebler-Wronski effect."That means that their efficiency drops when you expose them to light-pretty much the worst possible effect for a solar cell,"Pearce explains,which is one of the reasons thin-film solar panels make up only a small fraction of the market.However,Pearce and his team found a way to engineer around the Staebler-Wronski effect by incorporating thin-film silicon in a new type of PVT. You don't have to cool down thin-film silicon to make it work.In fact,Pearce's group discovered that by heating it to solar-thermal operating temperatures,near the boiling point of water,they could make thicker cells that largely overcame the Staebler-Wronski effect. When they applied the thin-fulm silicon directly to a solar thermal en-ergy collector,they also found that by baking the cell once a day,they boosted the solar cell's e-lectrical efficiency by over 10 percent. Which of the following statrnents is true?A: Thin-film silicon's electrical efficiency improves when heated up.B: New techniques have been developed to produce thin-film silicon.C: Thin-film silicon works efficiently at low temperature.D: A new material enlarging the Staebler-WronsKi effect has been created.
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California Gives Green Light to Space Solar PowerEnergy beamed down from space is one step closer to reality,now that California has given the green light to an agreement that would see the Pacific Gas and Electric Company buy 200 megawatts（兆瓦）of power beamed down from solar-power satellites beginning in 2016.But some major challenges will have to beovercome if the technology is to be used widely.A start-up company called Solaren is designing the satellites,which it says will use radio waves to beamenergy down to a receiving station on Earth.The attraction of collecting solar power in space is the almost uninterrupted sunshine available in geo- synchronous（与地球同步的）orbit. Earth-based solar cells , by contrast , can only collect sun light during day-time and when skies are clear.But space-based solar power must grapple（努力克服）with the high cost per kilogram of launching things in- to space,says Richard Schwartz of Purdue University in West Lafayette,Indiana."if you're talking about it being economically viable for power of the Earth,it's a tough go,"he says.Cal Boerman,Solaren's director of energy services,says the company designed its satellites with a view to keeping launch costs down."We knew we had to come up with a different,revolutionary design,"he says. A patent the company has won describes ways to reduce the system's weight,including using inflatable mir- rors to focus sunlight on solar cells,so a smaller number can collect the same amount of energy.But using mirrors introduces other challenges,including keeping the solar cells from overheating,says Schwartz."You have to take care of heat dissipation（散发）because you're now concentrating a lot of energy in one place,"he says.According to the company's patent,Solaren's solar cells will be connected to radia-tors to help keep them cool.Though Boerman says the company believes it can make space-based solar power work,it is not expec-ting to crowd out other forms of renewable energy.Laws in California and other states require increasing use of renewable energy in coming years,he points out."To meet those needs,we're going to need all types of renewable energy sources,"he says.Space-based solar cells could collect solar power only when skies are clear.A:RightB:WrongC:Not mentioned
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Google's Solar Energy Gambit（策略）Google is making its largest investment yet in clean energy,setting up a $280 million fund to finance home solar rooftop（屋顶）installations.The search giant announced today it was teaming up with the Silicon Valley's Solar City一a company chaired by Paypal co-founder and Tesla Motors executive Elon Musk一in an effort to break down the biggest barrier to solar energy adoption:the cost."It's a great way to support installations going into more homes,"said Google spokesperson Parag Chokshi.The $280 million fund is the largest fund ever created for residential solar in the United States,according to Solar City,which has raised a total of$I.28 billion in financing capacity during its five-year history.Google over the past several years has invested in large,utility-scale wind and solar,enhanced geothermal（地热）energy,and other renewable energy projects,for a grand total of more than $680 million in the sector. But today's deal is not only Google's largest foray（突袭）into the sector, it is its first investment in distributed energy. Based in San Mateo,California,less than 20 miles north of Google's Mountain View headquarters,Solar City describes itseff as a solar power service provider. The idea is that people want affordable,clean energy一but they often can't afford to buy a photovoltaic system upfront. Solar City is one of a number of companies that have attempted to help people overcome that cost hurdle（障碍）by leasing,instead of owning their rooftop solar systems.Solar City's leases and power-purchase agreements to homeowners,businesses,and schools promise a lower monthly electricity bill(including a set payment to Solar City in addition to utility payments)than customers would get with their usual electricity from the grid.Solar City not only finances these photovoltaic projects,but also designs,installs,monitors,and maintains the systems. Recently,since buying the assets of a company called Business Solutions last year,Solar City has also begun offering energy audits and small home improvements(like installing programmable thermostats)that can make a big difference in energy use.Until now,Solar City has financed most of its 15,000 projects through banks,Chief Executive Lyndon Rive said in an interview. But the problem is only about a half dozen banks are doing solar financing,he said.So in order for Solar City's model to achieve"true scale,"it must"unleash the available capital of corporate America,"he said.Rive is hopeful that Google's move today will set an example for other corporations to make similar investments. Google is the biggest clean energy company in the world.A:Right B:Wrong C:Not mentiond
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Google's Solar Energy Gambit（策略）Google is making its largest investment yet in clean energy,setting up a $280 million fund to finance home solar rooftop（屋顶）installations.The search giant announced today it was teaming up with the Silicon Valley's Solar City一a company chaired by Paypal co-founder and Tesla Motors executive Elon Musk一in an effort to break down the biggest barrier to solar energy adoption:the cost."It's a great way to support installations going into more homes,"said Google spokesperson Parag Chokshi.The $280 million fund is the largest fund ever created for residential solar in the United States,according to Solar City,which has raised a total of$I.28 billion in financing capacity during its five-year history.Google over the past several years has invested in large,utility-scale wind and solar,enhanced geothermal（地热）energy,and other renewable energy projects,for a grand total of more than $680 million in the sector. But today's deal is not only Google's largest foray（突袭）into the sector, it is its first investment in distributed energy. Based in San Mateo,California,less than 20 miles north of Google's Mountain View headquarters,Solar City describes itseff as a solar power service provider. The idea is that people want affordable,clean energy一but they often can't afford to buy a photovoltaic system upfront. Solar City is one of a number of companies that have attempted to help people overcome that cost hurdle（障碍）by leasing,instead of owning their rooftop solar systems.Solar City's leases and power-purchase agreements to homeowners,businesses,and schools promise a lower monthly electricity bill(including a set payment to Solar City in addition to utility payments)than customers would get with their usual electricity from the grid.Solar City not only finances these photovoltaic projects,but also designs,installs,monitors,and maintains the systems. Recently,since buying the assets of a company called Business Solutions last year,Solar City has also begun offering energy audits and small home improvements(like installing programmable thermostats)that can make a big difference in energy use.Until now,Solar City has financed most of its 15,000 projects through banks,Chief Executive Lyndon Rive said in an interview. But the problem is only about a half dozen banks are doing solar financing,he said.So in order for Solar City's model to achieve"true scale,"it must"unleash the available capital of corporate America,"he said.Rive is hopeful that Google's move today will set an example for other corporations to make similar investments. Google's move is an example for other corporations to make investments on renewable energy projects.A:Right B:Wrong C:Not mentiond
考题
共用题干
Google's Solar Energy Gambit（策略）Google is making its largest investment yet in clean energy,setting up a $280 million fund to finance home solar rooftop（屋顶）installations.The search giant announced today it was teaming up with the Silicon Valley's Solar City一a company chaired by Paypal co-founder and Tesla Motors executive Elon Musk一in an effort to break down the biggest barrier to solar energy adoption:the cost."It's a great way to support installations going into more homes,"said Google spokesperson Parag Chokshi.The $280 million fund is the largest fund ever created for residential solar in the United States,according to Solar City,which has raised a total of$I.28 billion in financing capacity during its five-year history.Google over the past several years has invested in large,utility-scale wind and solar,enhanced geothermal（地热）energy,and other renewable energy projects,for a grand total of more than $680 million in the sector. But today's deal is not only Google's largest foray（突袭）into the sector, it is its first investment in distributed energy. Based in San Mateo,California,less than 20 miles north of Google's Mountain View headquarters,Solar City describes itseff as a solar power service provider. The idea is that people want affordable,clean energy一but they often can't afford to buy a photovoltaic system upfront. Solar City is one of a number of companies that have attempted to help people overcome that cost hurdle（障碍）by leasing,instead of owning their rooftop solar systems.Solar City's leases and power-purchase agreements to homeowners,businesses,and schools promise a lower monthly electricity bill(including a set payment to Solar City in addition to utility payments)than customers would get with their usual electricity from the grid.Solar City not only finances these photovoltaic projects,but also designs,installs,monitors,and maintains the systems. Recently,since buying the assets of a company called Business Solutions last year,Solar City has also begun offering energy audits and small home improvements(like installing programmable thermostats)that can make a big difference in energy use.Until now,Solar City has financed most of its 15,000 projects through banks,Chief Executive Lyndon Rive said in an interview. But the problem is only about a half dozen banks are doing solar financing,he said.So in order for Solar City's model to achieve"true scale,"it must"unleash the available capital of corporate America,"he said.Rive is hopeful that Google's move today will set an example for other corporations to make similar investments. The biggest barrier to solar energy adoption is the cost.A:Right B:Wrong C:Not mentiond
考题
单选题A mean sun is used as the reference for solar time for three reasons. Which reason is NOT a cause for use of a mean sun?（）A
The motion of the apparent sun is along the eclipticB
Measurement of time is along the celestial equatorC
The speed of the Earth's revolution is not constantD
There are variations in the Earth's rotational speed
考题
判断题在中国传统的二十四节气中，由节气演变为节日的只有清明。A
对B
错
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