New York's iconic, blue-green statue of liberty wasn't always green. When the statue was gifted to the US from France in 1885, she was actually a shiny copper color. A new video reveals the chemical reactions involving oxygen and even air pollution that led to her color change from copper to liberty green. The statue of liberty was a gift from France to the US as a way of commemorating the US's fight for independence, as well as their own aspiration for democracy.

    A video, published by the American Chemical Society, explains that the 305-foot (93 meter) statue was built over nine years in sections of copper skin on top of an iron skeleton.

    In her first few decades in the Big Apple, the statue slowly turned from that shiny copper color to a dull brown and the, finally, to the blue-green, or as they'd say back in France, 'verdigris' we see today,' said the video's narrator.

When it changed color, some officials suggested restoring her back to her original color, but after the public protested against this decision, she was left the way she is. The statue's color change was as a result of oxidation reactions between copper and the air. But it was more than one reaction - the color change is due to about 30 years worth of different reactions leading to a mixture of greenish minerals.

    Oxidation reactions happen when an atom loses an electron to another atom.

    In the case of the statue of liberty, her color change was bound to happen due to oxygen in the atmosphere that is 'hungry' for electrons. On top of this, elements of New York City's polluted air added to the color change too.

The first chemical reaction of the color change involved copper giving up electrons to electron-hungry oxygen in the atmosphere. This led to a mineral called cuprite - which is pinkish red.

    Then, cuprite loses even more electrons to oxygen, forming a new mineral（矿物质） called tenorite, which is blackish in color. The black color of tenorite explains why the statue got darker over time, forming a dark brown color.

    Then, further chemical reactions occurred when sulfur（硫） in the atmosphere reacts with oxygen to form sulfur dioxide. Sulfur comes from natural processes such as volcanic eruptions, but also from man-made emissions from boats, cars, airplanes and factories. When sulfur dioxide in the atmosphere reacts with water, it produces sulfuric acid. Sulfuric acid forms green minerals with copper oxides, so the sulfuric acid in the atmosphere made the state green over time.

    Added to that, chloride from the sea spray surrounding Ellis Island where the statue is located made the statue even greener.

    The statue stayed this way for over 100 years because the exposed copper is now oxidized and stable, but the statue wouldn't be the same anywhere else.

    As sea levels climb, even Washington, D. C. could see more frequent and widespread flooding at high tide.

    Strong storms and high winds sometimes bring floods to coastal areas. But cities and towns along the US East Coast are flooding even in calm and sunny weather. Among them is Maryland's capital Annapolis. Tourists there must sometimes walk through water flooding downtown streets surrounding the habor. Sometimes water covers roads in Atlantic City, N. J. Even the yards and basements of coastal homes near New York City sometimes flood.

All are suffering from this trend—normal high tides surpass (超过) a rising sea level.

    Sea levels have climbed, on average, about 20 centimeters (8 inches) over the past 135 years. And a sharp increase in tide flooding is one of the more visible impacts affecting many coastal areas, notes William Sweet, an oceanographer.

    Sweet and his co-workers recently analyzed data from 45 tide gauges (计量表) along the US coasts. These tools record the changing heights of tides as they rise and fall. From these data, Sweet's team calculated the number of : “troublesome floods” in various coastal cities. These floods, Sweet explains, typically occur when water level is about 30 centimeters (1foot) above the historic level of the highest tides. In June 2014, the team reported finding a growing rise in these flooding events.

    In Charleston, S.C. from 1957 to 1963, the city experienced troublesome floods an average of 4. 6 days per year. Bur from 2007 to 2013, the occurring rate of troublesome floods jumped five times. Annapolis city was even more serious. From1957 to 1963，troublesome floods were roughly 3. 8 days per year. From 2007 to 2013, the average was 10 times higher- 39. 3days a year.

    “Over the next few decades, climate change probably drives sea levels even higher,” Sweet says. “So today's flooding problems promise to become only more widespread and frequent.”

    Many people have long dreamed of being able to fly around as simply as riding a bicycle. Yet the safety and strength of a flying bike was always a big problem. Over the past 10 years, developments in technology have moved the dream of personal flying vehicles closer to reality. Now, two groups of inventors say such vehicles may be available soon.

    The British company Malloy Aeronautics has developed a prototype (原型) of its flying bicycle. Grant Stapleton, marketing sales director of Malloy Aeronautics, says the Hoverbike is able to get in and out of small spaces very quickly." It can be moved across continents very quickly because it can be folded and packed," he adds.

    Mr. Stapleton says safety was the company's main concern. He says the designers solved the safety issue by using overlapping rotors to power the vehicle.

    The company is testing a full-size prototype of the Hoverbike, which will most likely be used first by the police and emergency rescue teams.

    In New Zealand, Martin Aircraft Company is also testing a full-size prototype of its personal flying device, called the Jetpack. It can fly for more than 30 minutes, up to 1, 000meters high and reach a speed of 74 kilometers per hour.

    Peter Coker is the CEO of Martin Aircraft Company. He said the Jetpack "is built around safety from the start". In his words, “Reliability is the most important element of it. We have safety built into the actual structure itself, very similar to a Formula One racing car.

    The Jetpack uses a gasoline-powered engine that produces two powerful jet streams. Mr. Coker says it also has a parachute that would be used, if there should be an emergency. "It starts to work at very low altitude and actually saves both the aircraft and the pilot," he adds. Mr. Coker says the Jetpack will be ready for sale soon.

Confucius Institute

    The Confucius Institute at the University of Minnesota offers several short classes on Chinese language and culture.

    Class Fees

    The cost of classes is $225 ($170 for Chinese Rehab)

    Class Calendar

    The Confucius Institute follows the University of Minnesota semester schedule. The Confucius Institute classes start a few weeks after the start of the University semester and last for ten class sessions. Classes are not held on University holidays.

    The upcoming class sessions will be:

    Spring 2018:  February 1- April 7

    Summer 2018: June 13- August 25

    Tentative class calendar:

    The schedule may change due to teacher availability.

    Class Cancellations

    Any class not meeting minimum enrollment by four business days before the class start date will be cancelled and you will be contacted. If we must cancel a class due to insufficient enrollment or any other circumstance beyond our control, we will offer a full refund or issue credit towards another class.

    Contact Information

    The Confucius Institute is located within the University International Center on the east bank of the Twin Cities campus. The University International Center is located in the Keeler Apartment building. Enter at the corner of 17th Avenue S.E. and 4th Street through the doors located near the     “University International Center” sign.

    Office hours

    The office is generally open Monday through Friday, from 8:00 a.m. until 4: 30 p.m.

The office is closed daily from12:.00 noon until 1: 00 p. m. and is closed on all University holidays.

    Office Address

    160 University International Center, 331-17th Ave. S.E., Minneapolis, MN 55414

    Phone: 612625-5080

    Fax: 612-625-5158

    Email: confucius@umn.edu

The history of Australian Rules Football

    Australian Rules Football is called by many nicknames. Lovers of the game just call it "football" or "footy." When contrasted with other forms of football, it is called "Aussie Rules" or "AFL". AFL stands for Australian Football League, which is the most prestigious league in Australia.

    Australia Rules Football was created by Tom Wills in 1858. He wanted to create a sport that would keep cricket players fit through the winter. He began by writing a letter that explained his purpose to a sports magazine. It also called for the creation of a football club. In 1858, Wills and others played an experimental match that was the first game of Australian football. But few details about this match have survived.

    On August 7, 1858, two important events for the game occurred. The Melbourne Football Club was founded. It was one of the world's first football clubs in any code. Also, a famous match between Melbourne Grammar School and Scotch College was played. It was umpired(仲裁)by Tom Wills. A second day of play took place on August 21, and then there was a third and final day on September4. The two schools have competed every year since.

    The game is played between two teams of 18 players on an oval that can also be used for cricket. These playing fields can be up to 185m long. This is almost four times the size of fields used in other forms of football.

    A point called "a behind" is scored when the ball goes across the line and between a goal post and a behind post. A behind point is also scored if the ball is touched by any body part of either team's member as it passes between the goal posts. A goal is worth six points, and a behind is worth one point.

    Researchers are looking into new ways to generate efficient photovoltaic energy (光伏能源) and for this they have been inspired by the v-shaped posture of the Cabbage White butterfly(菜粉蝶).

    Photovoltaic energy is the science behind solar power, where light is turned into electricity. It is a two-set process. Step one is a photoelectric effect, caused by sunlight. The second step is an electrochemical process, which generates an electric current.

    To improve the collection of sunlight, a research group has been inspired by the resting posture of the Cabbage White butterfly. The species has a natural range across Europe, Asia, and North Africa. To many farmers, the butterflies are regarded as a pest; to others, they are pretty to look at. To one research group the butterflies are an inspiration.

    The butterfly adopts a v-shape in order to heat up its flight muscles before taking off. By creating solar panels(太阳能电池板)in this formation，scientists think that the quantity of power that a solar panel can produce can be increased by around 50 percent.

    The Cabbage White butterfly is different to many other butterflies in using the v-formation. On cloudy days butterflies need to wait to receive enough sunlight in order to fly. However  by using the v-posture, the Cabbage White butterfly is able to take in more energy more quickly than other butterflies. In addition, the butterfly can reflect sunlight from its wings, which allows its flight muscles to be warmed to an ideal temperature.

    The new research was conducted at the University of Exeter's Environment and Sustainability Institute (ESI) and the Centre for Ecology and Conservation. Discussing the findings with Laboratory Manager magazine, lead researcher Professor Tapas Mallick stated :"Biomimicry(仿生学)in engineering is not new. However, this research shows pathways to develop low cost solar power that have not been done before. "