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    You may like chewing gum (口香糖) after meals to stop your breath smelling bad; or your mother might use a special neutralizer (调理剂) to protect her permed hair (烫发). But have you thought about the chemical principles behind such everyday actions?

    On March 2, the Senior 3 students from the IB (International Baccalaureate, 国际文凭) classes at Beijing Huijia Private School presented their discoveries, all in fluent English. This kind of seminar is held every year to show the achievements of the IB chemistry experiment lessons offered by the school. IB is a qualification based on a common curriculum (课程) for students aged 16-18 in any country and is recognized by universities everywhere.

    "Once I saw an advertisement for xylitol (木糖醇) gum," recalled Zhang Xinju. "Suddenly an idea came to my mind: are there any chemical reactions when the xylitol is working on our teeth?"

    Zhang and his partner Bu Xuan visited several hospitals to try and find out. "Doctors know that xylitol can protect teeth, but few could explain how the chemical reactions happen," said the 17-year-old boy.

    Presenting the results of their research in English to an audience of Chinese and foreign judges was never a problem for the students.

    "Textbooks for IB students are in English, and our teachers speak in English," explained Wei Duan and Han Yu, whose research topic was "The Acid-Base Reaction (酸碱反应) in the process of Hair-Perming".

    "In Senior 1 we often referred to Chinese textbooks, but we found we could understand and express it all in English by the second year."

    Lu Jiang, the school's IB chemistry teacher and China's only IB vice-examiner, is proud that her students can apply scientific theories they learn in class to daily life.

    "You might have learned these facts from you kindergarten teachers, but few think about the theories behind them," Lu said. "This kind of practice is intended to develop the scientific thinking they will need in their future studies."

Welcome to Adventureland!

    Everyone loves Adventureland! The parks and exhibitions were built for you to explore(探索), enjoy, and admire their wonders. Every visit will be an unforgettable experience. You will go away enriched, longing to come back. What are you going to do this time?

The Travel Pavilion

    Explore places you have never been to before, and experience different ways of life. Visit the Amazon jungle(丛林)village, the Turkish market, the Tai floating market, the Berber mountain house and others. Talk to the people there who will tell you about their lives, and things they make. You can try making a carpet, making nets, fishing…

The Future Tower

    This exhibition shows how progress will touch our lives. It allows us to look into the future and explore the cities of the next century and the way we'll be living then. Spend some time in our space station and climb into our simulator(模拟装置)for the Journey to Mars!

The Nature Park

    This is not really one park but several. In the Safari Park you can drive among African animals in one of our Range Cruisers: see lions, giraffes, elephants in the wild. Move on to theOcean Park to watch the dolphins and whales. And then there is still the Aviary to see…

The Pyramid

    This is the center of Adventureland. Run out of film, need some postcards and stamps?

    For all these things and many more, visit our underground shopping center. Come here for information and ideas too.

    Electrical devices (仪器) could soon use power made by human energy. Scientists say they have developed an experimental device that produces electricity from the physical movement of a person walking. British scientist Max Donelan and other scientists in Canada and the United States developed the device.

    The device connects to a person's knee. As the person walks, the device captures energy each time the person slows down. To do this, the device helps with the slowing down movement of the leg. The movements of the walking person push parts of a small machine that produces electricity. Using the device, an adult walking quickly could produce thirteen watts of electricity in just a minute. Donelan says walking at that speed could produce enough power to operate a laptop computer for six minutes.

    There are several possible uses for the device. Developers say it could help people who work in areas without electricity to operate small computers. The device could also be used in hospitals to operate heart pacemakers (起搏器). It could even be used to assist in the movement of robotic arms and legs.

    The experimental version of the device weighs about one and a half kilograms, but it is too costly for most people to buy. But the researchers hope to make a lighter, less costly version. An improved version should be ready in one year.

    The developers hope the device will one day help developing countries. Nearly twenty-five percent of people around the world live without electric power.

    A similar product was invented in 2005 by Larry Rome of the University of Pennsylvania. He created a bag carried on a person's back that also produces power from walking. The knee device does not produce as much electricity as the bag. But the bag requires the walker to carry a load of twenty to thirty kilograms.

    In 1978, I was 18 and was working as a nurse in a small town about 270 km away from Sydney, Australia. I was looking forward to having five days off from duty. Unfortunately, the only one train a day back to my home in Sydney had already left. So I thought I'd hitch a ride (搭便车).

    I waited by the side of the highway for three hours but no one stopped for me. Finally, a man walked over and introduced himself as Gordon. He said that although he couldn't give me a lift, I should come back to his house for lunch. He noticed me standing for hours in the November heat and thought I must be hungry. I was doubtful as a young girl but he assured （使…放心）me I was safe, and he also offered to help me find a lift home afterwards. When we arrived at his house, he made us sandwiches. After lunch, he helped me find a lift home.

Twenty-five years later, in 2003, while I was driving to a nearby town one day, I saw an elderly man standing in the glaring heat, trying to hitch a ride. I thought it was another chance to repay someone for the favour I'd been given decades earlier. I pulled over and picked him up. I made him comfortable on the back seat and offered him some water.

    After a few moments of small talk, the man said to me, “You haven't changed a bit, even your red hair is still the same.”

    I couldn't remember where I'd met him. He then told me he was the man who had given me lunch and helped me find a lift all those years ago. It was Gordon.

    Arthur Dubois isn't your typical grandfather. That's because at 72 years old, the Chicago resident is a newly discovered hip-hop artist.

    This week, Dubois walked into Haven Studios, a music program on the South Side of Chicago that supports young ambitious artists. The owner of Haven Studios, Andre "Add-2" Daniels, said Dubois claimed he was "young at heart." So, Daniels decided to listen to Dubois' music. He was completely floored. Daniels quickly took videos showcasing Dubois' talents and posted them to Twitter. His tweet went viral, receiving thousands of reactions within a matter of days. Now, Dubois' talents have even caught the attention of some famous hip-hop producers.

    "It's not what you would expect, right?" Daniels says in one of the videos. Dubois music is playing in the background, giving a steady beat that easily invites listeners to dance.

    Dubois said his style was entirely self-taught. He first started teaching himself to produce hip-hop beats about six years ago, after he retired. "I found something to do," he told NPR's Scott Simon. "I had to learn how to do the computer and music at the same time." Dubois taught himself by using the audio editing software. Now he's learning another new skill-social media. Dubois' newfound social media fame has been a little overwhelming for him. "I was shocked," he said. "I broke down and cried because I didn't know that many people liked me." Daniels has helped Dubois set up accounts on Twitter and Instagram for his fans to follow, "I'd never used Instargram, Twitter and all that other stuff," Dubois said. "Because I didn't believe in that stuff myself. But now I've got to have it." The attention doesn't seem to have gone to Dubois' head though-he doesn't really care about getting famous or making money. "I just want to put it out there and let other people hear my music."

    With the possible exception of equal rights, perhaps the most controversial issue across the United States today is the death penalty. Many argue that it is an effective deterrent (威慑) to murder, while others maintain there is no convincing evidence that the death penalty reduces the number of murders.

    The principal argument advanced by those opposed to the death penalty, basically, is that it is cruel and inhuman punishment, which is the mark of a brutal society, and finally that it is of questionable effectiveness as a deterrent to crime anyway.

    In our opinion, the death penalty is a necessary evil. Throughout recorded history there have always been those extreme individuals in every society who were capable of terribly violent crimes such as murder. But some are more extreme than others.

    For example, it is one thing to take the life of another in a fit of blind rage, but quite another to coldly plot and carry out the murder of one or more people in the style of a butcher. Thus, murder, like all other crimes, is a matter of relative degree. While it could be argued with some conviction that the criminal in the first instance should be merely separated from society, such should not be the fate of the latter type murderer.

    The value of the death penalty as a deterrent to crime may be open to debate. But the overwhelming majority of citizens believe that the death penalty protects them. Their belief is strengthened by evidence which shows that the death penalty deters murder. For example, from 1954 to 1963, when the death penalty was consistently imposed in California, the murder rate remained between three and four murders for each 100,000 population. Since 1964 the death penalty has been carried out only once, and the murder rate has risen to 10.4 murders for each 100,000 population. The sharp climb in the state's murder rate, which began when executions stopped, is no coincidence. It is convincing evidence that the death penalty does deter many murderers. If the bill reestablishing the death penalty is banned, innocent people will be murdered—some whose lives may have been saved if the death penalty were in effect. This is literally a life or death matter. The lives of thousands of innocent people must be protected.