A cellphone is one of the few things that we hold close to our faces all the time, and yet it could possibly explode - this is what made the recent Samsung's Galaxy Note 7 smart-phone accidents so shocking.

   According to technology news website The Verge, flawed（有瑕疵的）phone batteries might be to blame.

    Even if you are not a science student, you probably know that it is common sense that the anode (the negative（负的）end of the battery) and the cathode (the positive end) should never touch. If they do, the battery will short-circuit（短路）, causing a powerful electrical reaction that can destroy the battery and cause a fire.

    This is why all lithium-ion（锂离子）batteries - the kind that can be found in many of our devices like tablets and cameras - have a separator layer inside to stop the two ends from touching one another.

    But somehow, the separators in some of the Samsung phones broke, causing explosions.

    Overcharging is another problem that can make batteries heat up quickly. Fortunately, most batteries are designed to be able to automatically stop charging once they are fully charged. But again, this somehow failed to happen in some of the Samsung phones.

    The two “somehows” may sound random（随机的）and hard to explain. But they actually both come from the fact that phone producers have been pushing the limits of batteries to meet customers' demand for a longer battery life.

    According to Lynden Archer, a materials scientist at Cornell University, US, we have already achieved 90 percent of the battery life possible from a lithium-ion battery. Customers' demand that their devices get thinner has also given producers little choice but to try to put more power into thinner batteries.

     “The more energy you put into a box, the more dangerous it's going to be,” Billy Wu, a lecturer at Imperial College London, told The Guardian.

    A thinner battery also means producers have to use thinner material for separators, and thinner material has more chance of breaking.

    Making friends is a skill like most skills. It improves with practice. If you want to meet people and make friends, you must be willing to take some action. You must first go where there are people. You won't make friends staying home alone.

    Joining a club or a group, talking with those who like the same things as you do is much easier. Or join someone in some activity.

    Many people are nervous when talking to new people. After all meeting strangers means facing the unknown. And it's human nature to feel a bit uncomfortable about unknown. Most of our fears about dealing with new people comes from doubts about ourselves. We imagine other people are judging us, finding us too tall or too short, too this or too that. But don't forget that they must be feeling the same way. Try to accept yourself as you are, and try to put the other person at ease. You'll both feel more comfortable.

    Try to act self-confident even if you don't feel that way. When you enter a room full of strangers, such as a new classroom, walk tall and straight, look directly at other people and smile.

    If you see someone you'd like to speak to, say something. Don't wait for the other person to start a conversation.

    Just meeting someone new does not mean that you will make friends with that person—friendship is based on mutual liking and “give and take”. It takes time and effort to develop.

    This contest from the Winchester Poetry Festival is intended for “surprise and delight”. However, don't try to surprise and delight them with a short story or a photo of your cat dancing in a Tutu. Stick to a poem of up to 40 lines.

    Closing: Quarterly.

    Prizes: £1,000, £500, £250.

    Entry Fee: £5.

    Starts Theatre One-Act Play Competition

    This annual contest from Strerts Theatre in Cornwall is for plays for up to four adult actors, with a running time of between 25 and 35 minutes. Plays can be on any theme; you need to be 18 or over to enter.

    Closing: Annually.

    Prizes: £100 plus performance of your play in Sterns Studio.

    Entry Fee: £7.

    Artificium Short Stories & Poetry Prizes

    This one from Artificium, a journal of new fiction and poetry, has two categories: Short Stories and In Brief. The former is for stories of between 2,000 and 8,000 words in any genre（体裁）. The latter is for poetry of between 500 and 1,000 words.

    Closing: End of each month.

    Prizes: £200, £100, £50.

    Entry Fee: £5 for one, £9 for two.

    PENfro Open Poetry Competition.

    This contest from the PENfro Book Festival is for poems of up to 40 lines on any subject and in any style. Costa Award winning poet Jonathan Edwards, whose taste in poetry is broad-ranging, will be judging.

    Closing: End of each month. Prizes: £300, £100, £75. The top ten winners will be invited to read their works at a spoken word event at which Jonathan Edwards will present the prizes.

    Entry Fee: £4.

    Tiny Countries You Never knew Existed

    Sao Tome and Principe

    Sao Tome and Principe off Africa's west coast is only 372 square miles, but it has Impressive, undamaged nature, rich in biodiverse species. The amazing needle-like volcanic peak Pico Cao Grande rises 1,000 feet into the air. The islands are home to only around 200,000 people today.

    San Marino

    Only 23 square miles with a population of just 34,000, the little-known country of San Marino, surrounded by Italy, is the world's fifth smallest country. With the UNESCO World Heritage Site of Mount Titano, the country is said to be the oldest republic in the world.

    Dominica

    Dominica covers only 290 square miles, with some of the best diving in the Caribbean, including the UNESCO World Heritage Site of volcanic Morme Trois Pitons National Park. In Dominica, you'll see rainforests, waterfalls, and coastal views. The island is also home to the only remaining population of the Kalinago, who are part of the island's 74, 900 inhabitants.

    Kiribati

    This Pacific island country 33 coral islands is 313 square-miles, but it's the only country in the world to fall into all four hemispheres (半球). The country's 109, 000 residents live in only 21 of the islands see this tropical paradise before it is no longer--rising seas are threatening to swallow the country whole.

    During your four years in the college, you'll have many exciting choices to make, the first of which will be your course selection for your first semester. The beauty of this choice is that you can't go wrong! No matter which one of our First-Year Options you select to apply for, you will create a rich intellectual experience to begin your college career.

    Option 1: Liberal Arts Seminar

    The Liberal Arts Seminar is a multidisciplinary(多学科的)course that explores the cultural history of the Mediterranean through fictional and nonfictional books.

Fall schedule: When Registration opens, you will select between one and four additional courses to complete your schedule.

    Option 2: FLL Hager Scholars Program

    The FLL Hager Scholars Program is designed with our most ambitious students of languages and linguistics in mind, and is designed to create for them both a sense of community and opportunities for intellectual growth.

    Fall schedule: When Registration opens, you will select between one and three additional courses to complete your schedule.

    Option 3: Ignatius Seminars

    Offered only in the first semester, Ignatius Seminars introduce students to the depth and diversity of Georgetown's dynamic intellectual community.

    Fall schedule: When Registration opens, you will select three or four additional courses to complete your schedule.

    Option 4: Traditional First-Year Academic Program

    With this program, you'll take your first step into the college's rich and varied core courses and explore your fields of interest in free optional coursework.

    Fall schedule: When Registration opens, you will build a schedule of four or five additional courses from the full college curriculum.

    A young woman turns around and around quickly, and jumps high. In the background, a young girl reads a rejection (拒绝) letter from a ballet school. "You have the wrong body for ballet," it says, "and at thirteen, you are too old." This was one of the most popular advertisements (广告) of 2014 and it describes American ballet Theatre's principal (主要的) dancer Misty Copeland.

    This was not a real letter. But Copeland says it is very similar to letters from her childhood. While many dancers start at the age of three. Copeland only began to study ballet in 1995 as a thirteen-year-old.

    People often told her that she was too old, or that she didn't have the perfect body type (She is only 157 cm tall). Her family moved a lot, and it was sometimes difficult for her to attend ballet classes. But Copeland loved dancing and did not want to give up. She stayed with her ballet teacher during the week and spent time with her family only at the weekend. This was a difficult life, but she worked hard and won her first national competition when she was fourteen years old. Copeland joined the American Ballet Theatre in 2000 and performed in many ballets over the next few years. In 2007, she became a solo (单独的) performer, and in 2015 she became its principal dancer.

    Copeland is now a dancer, author and Broadway performer. She also stars in the 2015 film A Ballerina's Tale. So what's next? According to Copeland, anything is possible: "My career (职业) really is just now beginning."