What will power your house in the future？Nuclear, wind, or solar power？According toscientists at the Massachusetts Institute of Technology(MIT)in the US, it might beleaves—but artificial(人造的)ones.

    Natural leaves are able to change sunlight and water intoenergy. It is known as photosynthesis(光合作用). Nowresearchers have found a way to imitate this seemingly simple process.

    The artificial leaf developed by Daniel Nocera and hiscolleagues at MIT can be seen as a special silicon chip with catalysts(催化剂). Similar tonatural leaves, it can splitwater into hydrogen and oxygen when put into a bucket of water. The hydrogenand oxygen gases are then stored in a fuel cell, which usesthose two materials to produce electricity, located eitheron top of a house or beside the house.

Though the leaf is only about the shape of a poker card, scientistsclaimed that it is promising to be an inexpensive source of electricity indeveloping countries.“ One can imagine villages in India and Africa not longfrom now purchasing an affordable basic power system based on this technology, ”said Noceraat a conference of the American Chemical Society.

    The artificial leaf is not a new idea. The first artificial leafwas invented in 1997 but was too expensive and unstable for practical use. Thenew leaf, by contrast, is made ofcheap materials, easy to useand highly stable. In laboratory studies, Nocera showedthat an artificial leaf prototype(原型)could operatecontinuously for at least 45 hours without a drop in activity.

    The wonderful improvements come from Nocera's recent discoveryof several powerful, new andinexpensive catalysts. These catalysts make the energy transformation insidethe leaf more efficient with water and sunlight. Right now, the new leafis about 10 times more efficient at carrying out photosynthesis than a naturalone. Besides, the device canrun in whatever water is available；that is, it doesn'tneed pure water. This is important for some countries that don't have access topure water.

    With the goal to “make each home its own power station” and“give energy to the poor”, scientistsbelieve that the new technology could be widely used in developing countries, especially inIndia and rural China.

    The expression “a thirst for knowledge" may soon have a new meaning for millions of people who have no way to get clean water. Researchers have developed a book with specially treated pages that can turn dirty water into clean and drinkable water. They say their invention could improve the lives of many in the developing world.

    About 700 million people around the world are at risk of disease or even death because their drinking water is not clean. The water is polluted by harmful bacteria.

    The book contains 25 pages. Each page is about one millimeter thick. The pages contain very small particles (微粒) of silver. The pages can be used as filters（过滤器）to remove harmful microorganisms (微生物) that can pollute drinking water. The filter kills the organisms that pass throughit.

    Pictures on the pages show the dangers of dirty water and how to use the book for those unable to read. The pages aremade of filter paper. They are designed to be torn from the book. Water can bepoured through the paper to be cleaned.

    Ms. Dankovich, the inventor, says eachpage can treat up to 100 liters of water. She recently presented her invention at the meeting of the American Chemical Society in Boston, Massachusetts. She was asked whether she had considered adding classic literature on the book's pages.

    "The idea of classic texts—that's of interest maybe later. We have discussed a little bit more exciting text. But we really haven't had the time to go through that part," she says.

    Teri Dankovich and another researcher tested the drinkable book in Bangladesh, Ghana and South Africa. The tests proved to be successful.

    Water for Life, a non-government alorganization, has provided financial support for the project.

    I was at my parent's dinner table. Before me was a worn journal of thin and discolored pages. It was my grandfather's journal and now belonged to my father. My grandfather had passed away in the months leading up to my birth. I never got to visit the places he had frequently and people who had been a part of his life's journey.

    I was now about to enter his world, through the words he had left behind. Within minutes, I was attracted by the power of the written words. In the magical script before me, I was transported to another age when food was an everyday art, planned, prepared and enjoyed in the company of others, and a time when people had the heart to pause，their own lives to embrace (拥抱）each other's struggles. All this was conveyed to me in the beauty of the words that flowed together to connect with the writer's mind and understand the world they lived in.

    That kind of writing seems to be lost on us today. We have gotten used to writing in bite-sized pieces for a public looking for entertainment, and hungry for information. No wonder, there are nearly 200 million bloggers on the Internet and a new blog is created somewhere in the world every half a second. Instead of adding to our collective wisdom, most of these writings reflect the superficiality (肤浅)and impatience of our day and age.

    This not only robs us of the skill of writing impressive essays, it also prevents us from exploring what is truly important. Writing humbles us in a way that is vital for our character growth, by reminding us about the limits of the self and our appropriate place in the vast flow of life. Writing frees us by helping us explore the unknown so that we truly open up to the magic of the world around us. I saw all of this in the writing s of my grandfather. And I've seen it again and again in the writings of the greatest thinkers of humanity. Their writings reflect deep thought on issues of human importance.

    The National Gallery

    Description:

    The National Gallery is the British national art museum built on the north side of Trafalgar in London. It houses a diverse collection of more than 2,300 examples of European art ranging from 13th-century religious paintings to more modern ones by Renoir and Van Gogh. The older collections of the gallery are reached through the main entrance while the more modern works in the East Wing are most easily reached from Trafalgar Square by a ground floor entrance.

    Layout:

    The modern Sainsbury Wing on the western side of the building houses 13th-to15th-century paintings, and artists include Duccio, Uccello, Van Eyck, Lippi, Mantegna, Botticelli and Memling.

    The main West Wing houses 16th-century paintings and artists include Leonardo da Vinci, Cranach, Michelangelo, Raphael, Bruegel, Bronzino, Titian and Veronese.

    The North Wing houses 17th-century paintings and artists include Caravaggio, Rubens, Poussin, Van Dyck, Velazquez, Claude and Vermeer.

    The East Wing houses 18th-to early 20th-century paintings, and artists include Canaletto, Goya, Turner, Constable, Renoir and Van Gogh.

    Opening Hours:

    The Gallery is open every day from 10am to 6pm（Fridays 10am to 9pm）and is free, but charges apply to some special exhibitions.

    Getting There:

    Nearest underground stations: Charing Cross (2-minute walk). Leicester Square (3-minute walk), Embankment (7-minute walk), and Piccadilly Circus (8-minute walk).

    Sam, I say to myself as I start across the bridge, you must stop these thoughts and start thinking about what to do now that you have lost your falcon（猎鹰）, Frightful.

    Life, my friend Bando once said, is meeting problems and solving them whether you are an amoeba or a space traveler. I have a problem. I have to provide my younger sister Alice and myself with meat. Fish, nuts, and vegetables, are good and necessary, but they don't provide enough fuel for the hard physical work we do. Although we have venison（鹿肉） now, I can't always count on getting it. So far this year, our venison has been only road kill from in front of Mrs. Strawberry's farm.

    I decide to take the longest way home, down the flood plain of the West Branch of Delaware to Spilkill, my own name for a fast stream, that cascades down the south face of the mountain range I'm on. I need time to think. Perhaps Alice and I should be like the early Eskimos. We should walk, camp and hunt, and when the seasons change, walk on to new food sources. But I love my tree and my mountaintop.

    Another solution would be to become farmers, like the people of the Iroquois Confederacy who once lived here. They settled in villages and planted corn and squash（南瓜）, bush beans and berries. We already grow groundnuts in the damp soil and squash in the poor land. But the Iroquois also hunted game. I can't do that anymore

    I'm back where I started from.

    Slowly climb the Spillkill. As I hop from rock to rock beneath shady basswoods and hemlocks, I hear the cry of the red﹣tailed hawk who nests on the mountain crest. I am reminded of Frightful and my heart aches. I can almost hear her call my name, Cree, cree, car-ree.

    Maybe l can get her back if l beg the man who is in charge of the peregrines（游隼） university. "But it's the law," he would say. L could write to the president of the United states and ask him to make an exception of Alice and me. That won't work. The president swore to upload the constitution（宪法） and laws of the United States when he took office.

    I climbed on. I must stop thinking about the impossible and solve the problem of what to do now. I must find a new way to provide for us. Frightful is going to be in good hands at the university and she will have young.

    I smile at the thought of little Frightfuls and lift my reluctant feet.

    When I am fat above the river,1take of my clothes and moccasins（鹿皮鞋） and bathe in a deep, clear pool until I am refreshed and thinking more clearly. Climbing up the bank, I dress and sit down. I breath deeply of the mountain air and try to solve my problem more realistically.

    About 6 years ago, I was on a plane next to a woman. I was tired and wanted to take a nap. But before I could go into "ignore pattern", she tapped me on the shoulder to introduce herself.

    "Hi, my name is Helga!"

    We got to talking and eventually it came up that I had started an organization in high school called R.A.K.E.(Random Acts of Kindness, Etc.). As I described what we did, Helga got very serious and told me that she admired me for that. She told me a story about the last time she had flown. She was on the way to Arizona because she had gotten sudden news that her dad's health was on the decline. Later her father's physician called to inform her that her dad had rather suddenly passed away. For the 3-hour plane ride, she sat in silence around strangers.

    When she arrived at the airport in Arizona, she walked to the nearest wall, sat down, and cried. And here is the part I'll never forget about Helga's story. For 2 hours she sat and wept while thousands walked to and fro in the airport. Helga looked at me and said, "Houston, not a single person stopped and asked if I was okay that day." It was that day that I realized how much we need each other. It was that day I realized that kindness isn't normal.

    Kindness isn't normal. That has stuck with me all these years especially now. I work in schools nationwide speaking about sympathy, kindness, empathy (同理心) and love. I'm reminded all the time that, for many of us, kindness is not usually our default setting. We spend so much time worrying about our problems, our lives, our insecurities, getting to our flight so we walk by or ignore people in need of help.

    So, I've made it my mission to do my part in sharing stories with students, teachers, and parents about our need for character and sympathy. I'm always be on the lookout for the little opportunities that surround me every day to do something nice.