Most people don't think too much about chemicals, but actually they are all around us. Many substances consist of chemicals, including the air that we breathe and the water that we drink. Some chemicals are natural, but most of them are artificial and may be harmful to the human body.
In 2005, Hurricane Katrina struck the United States, so displaced people had to move into temporary housing. Later, some of them began experiencing headaches and nosebleeds due to Formaldehyde exposure. This chemical is commonly found in the glue that holds many household products. It was proved to cause cancer in 2011 and has been linked to an increase in allergies it children.
However,there is another choice: natural adhesives(黏合剂). In particular, one is made from plants such as soy(豆类)proteins that have been changed to resemble the protein some shellfish use to stick to rocks. A natural adhesive is now widely used in wood products in the U.S. Other companies are also developing more natural alternatives to replace industrial chemicals. This is a part of the Green Chemistry philosophy.
Green Chemistry is a way of rethinking how to develop products and processes that are more environmentally-friendly and better for people's health. That includes reducing processing waste, using renewable materials. The 12 Principles of Green Chemistry lay out the goals of this approach. The first is prevention. It is better to prevent waste than to treat it or clean it up. Another principle encourages less dangerous chemical synthesis(化合). Chemical reactions should be designed to be as safe as possible. Energy efficiency is encouraged as well as using chemicals made from renewable plant-based sources.
There are challenges in meeting and holding to the principles of Green Chemistry, but this will encourage new research and lead to the discovery of new chemistry.
1. Why does the author mentioned the incident that happened in 2005?A.To make comparisons. | B.To prove a point. |
C.To introduce a chemical. | D.To bring in the topic. |
A.Wood from trees | B.Proteins from shellfish |
C.Processed plant proteins. | D.Melted special rocks |
A.The definition and purpose of Green Chemistry |
B.How to make environmentally. friendly products |
C.Ways to reduce the amount of waste in daily life |
D.Reasons for promoting Green Chemistry in the world. |
A.Wonderful but impractical |
B.Challenging but inspiring |
C.Admirable and popular. |
D.Complex and discouraging |
相似题推荐
【推荐1】We often wake up in the middle of the night with our mouths feeling dry even if we have drunk some water before going to bed. Feeling thirsty in the middle of the night has something to do with a lack of water.
First of all, take a good look at how many glasses of water you’ve really drunk during the day.
It’s not just what you drink during the day that influences your thirst at night.
A good solution for nightly thirst is to drink enough water during the day and to avoid salty foods as much as you can. Also, prepare yourself by placing a big glass of water by your side before going to bed.
A.That results in your losing more water |
B.The smartest way is to go to see a doctor |
C.Food you eat can also be very influential |
D.You don’t take a lot of coffee in the daytime |
E.You’ve really drunk eight glasses during the day |
F.This will help you fall asleep again more quickly after drinking |
G.Yet there are many different reasons why you’re feeling so thirsty |
【推荐2】Mother Nature never fails to surprise us with something extraordinary and unusual from time to time. There will always be news about something completely different that will surely grab eyeballs.
Blood Falls (Antarctica)
As the name suggests, Blood Falls is a waterfall which shoots blood-red water into a river. The sight is a perfect backdrop for a horror film; mysterious and of course bloody. Previously, red algae (红藻) were believed to cause the water to change its colour and turn blood-red. Until 2017, the true origin of the so-called blood was revealed to be oxidized iron in saltwater.
Frozen Bubbles (Canada)
Impressive yet a dangerous sight, frozen bubbles (气泡) can be seen in winters at Abraham Lake in Canada. The phenomenon occurs when methane (甲烷) gas gets trapped underwater, freezes, and forms other-worldly visuals. Such a large amount of methane trapped is highly risky. So even a lit match nearby can cause a giant explosion.
Hidden Beach (Mexico)
Located only a few miles off Mexico’s coast, the hidden beach was caused by an explosion by the Mexican Government as part of target practice. The beach is now every lover’s dream destination. To get there, you must ride an hour-long boat. Once you land on the island, you have to travel through the waters to reach there.
Sky Mirror (Malaysia)
During the new moon and full moon periods, tourist can see a clear reflection of the sky in the waters of Sasaran Beach. This natural phenomenon occurs because the tides are the lowest during these days. The smooth sand and minimal water level create such an incredible sight. Also known as the “Mirror of the Sky”, this shallow water beach is an amazing place to click pictures and thus a perfect travel destination.
1. Why is the water shot by Blood Falls blood-red?A.Saltwater there contains oxidized iron. |
B.The waterfall has supernatural powers. |
C.Red algae causes the water to change its color. |
D.A film factory reddened the water for a horror scene. |
A.Admiring Blood Falls. | B.Exploring Frozen Bubbles. |
C.Boating along Hidden Beach. | D.Taking pictures against Sky Mirror. |
A.They can be accessible only by water. |
B.They attract millions of tourists across the world. |
C.The causes of their formation have been revealed. |
D.Tourists may enjoy a better travelling experience in winter. |
【推荐3】The deserts of the world are not all covered with sand. Many of them have surfaces of rock or clay or small stones. They are not flat, either. They often have high hills and deep valleys. There is some plants’ life in many parts of the desert. There is little rain in the desert, but it does fall often enough for most plants.
The deserts of the world are not uninhabited (not lived by people). People also live outside oases (绿洲), but these people are not farmers. They have camels, goats, donkeys, sheep, etc. These animals can live on the desert plants and do not need much water.
The people of the desert have to move constantly from place to place, they must always look for grass or desert plants for their animals. They usually live in tents. When there is no more food for their animals, they fold up their tents, pat them on their camels and donkeys, and move to another place. In good years, when there is enough food for their animals, they trade their skins and their goats and camel hairs with the people of oases for wheat and fruit. But in bad years, when there is not enough food for their animals, the people of the desert would attack the oases people. But they are also hospitable, no man in the desert would ever refuse to give a stranger food and water.
1. The underlined word “hospitable” has the meaning of being ________.A.brave | B.cruel | C.strange | D.kind |
A.it rains in spring only | B.there is some rain, but far from enough |
C.it rains for a short time every month | D.the rainfall is just enough for the plants |
A.only inside the oases | B.only outside the oases |
C.both inside and outside the oases | D.in places with regular rainfalls |
A.is hard in deserts | B.is happy in deserts |
C.is impossible in deserts | D.in deserts is much better now |
【推荐1】A four-year-old boy who was crazy about collecting rubbish has finally fulfilled his dream of being a cleaner. Riley McCourt has admired the local rubbish collectors for ages, spending his days picking up waste on his street and wheeling bins (垃圾桶) to the side of the road to help out his neighbors. He loves cleaning and binning waste. His favorite chore is to empty the rubbish from the chip shop his mum runs. Two weeks ago, however, a disaster struck: Riley accidentally knocked over one of the bins and was accused of causing trouble.
Someone posted in the local Facebook group that Riley had put rubbish in the street, clearly unaware of his love for keeping the streets clean. Thankfully his innocence was quickly proven, and his local council decided to make his dreams come true by allowing him to work alongside the cleaners for a day.
Riley joined the waste collection crew on Wednesday, chatting with the team, helping with the recycling, and riding in the waste collection vehicles. He even got his own jacket. Riley's mum, Toni McCourt, said, “He loves the bins and trucks.” Riley's favorite day is definitely bin day. He goes round collecting the rubbish up on the street. The cleaners all know him when they spot him. He goes outside as soon as he sees them come round. He helps his neighbors put their bins out for collection.
Riley clearly made a good impression during his first day on the job, as community services manager Jane Carrol said she was very pleased with his enthusiasm for the role. Jane said, “Riley is clearly a keen recycler and who knows, when he is older I'm sure he would make an excellent member of the team here. It was a pleasure for the team to show him around the vehicles.”
1. What is Riley's dream?A.To prove his innocence. |
B.To collect much rubbish. |
C.To work as a real cleaner. |
D.To work in his mother's shop. |
A.He was wronged by someone. |
B.He was knocked over by a bin. |
C.He had an accident in the shop. |
D.He forgot to empty the rubbish. |
A.People go out to celebrate it. |
B.The cleaners collect the bins. |
C.People help Riley collect rubbish. |
D.The cleaners collect rubbish in the bins. |
A.It is dangerous to do so on the street. |
B.It is good for the community to follow him. |
C.It is worthwhile to give Riley high remarks. |
D.It is unnecessary for such a little boy to do so. |
【推荐2】Our mother earth is going through a very tough situation and we, the entire human race, are destroying our environment or unconsciously without even realizing its consequences. Now we have to act very smartly and plan something to sustain what we still have, getting all necessary support from nature to lead healthy lives.
Gardening is always an excellent and environmentally friendly idea. If you can go for sustainable gardening, then it will be even more useful for all. Gardening is a favorite hobby for many. It is time to channelize your hobby towards a more meaningful motivation.
When we do gardening we need to use different ingredients(材料) to grow plants. Some of them are natural resources like water, soil, sunshine, and many things like this. Using these resources smartly is a part of sustainable gardening. Some simple techniques include: use less water and organic things to grow plants; try to store rainwater so that you can use them for gardening; try using less energy to drive devices; avoid using plastics in any form while gardening; reuse the leaves from your garden to fertilize them. These are the basic sustainable measures. To do so we need to have proper knowledge about gardening and its requirements so that we can use proper resources without wasting any of them.
In today’s busy life we don’t get much time to spend on our environment. Gardening gives us a chance to do so. We can also have some pesticide-free(无农药的) and fresh food if we grow them in our garden. This is the right time to do some good to protect our own environment and gardening is one of the easiest ways. Do you want to start gardening, but you’re not sure how? Click here: http://www. gardenhowto. com.
1. What does the underlined word “channelize” in Paragraph 2 refer to?A.Cause. | B.Transform. |
C.Direct. | D.Associate. |
A.Using advanced electrical machines. |
B.Avoiding fertilizers. |
C.Watering plants with collected rainwater. |
D.Clearing away the leaves. |
A.It requires little water. | B.It needs no fertilizer. |
C.It breaks up plastics. | D.It doesn't waste any resource. |
A.A newspaper. | B.The Internet. |
C.A guidebook. | D.A science report. |
【推荐3】To produce the classic clothing, blue jeans, producers rely on indigo dye (靛蓝染料), the only molecule known to provide jeans’ unique, beloved color. While indigo itself naturally comes from a plant, growing demand for blue jeans throughout the 20th century gave rise to synthetic (合成的) indigo, which is now more commonly used.
Indigo is the dye that makes jeans blue, but it doesn’t mix with water. To dye clothes, usually, chemicals are needed to make the color stick to the cloth. But in Denmark, scientists have created a new way to dye clothes using an enzyme (酶), which is a kind of protein that can cause chemical reactions, instead of harmful chemicals. This new method is better for the environment and doesn’t use poisonous stuff.
The chemical process for dyeing blue jeans has persisted for the last century. Workers are exposed to the poisonous chemicals, which also pollute the environment near factories. Waste water from those factories often ends up in waterways, decimating local ecosystems and even dyeing rivers blue.
Ditte Hededam Welner, the study’s lead researcher, says their new enzyme works really well and is strong enough for making lots of jeans without breaking down. This enzyme makes dyeing with indican, which is like indigo, much less harmful to the planet — about 92% better than the old way.
However, the new method doesn’t fix all the environmental problems of making jeans. Making a single pair of jeans uses a lot of water — enough to fill many bathtubs — from growing the cotton to putting the final touches on the jeans.
Even though the new dyeing process is better for the environment, it’s not always easy or cheap to change to it. Welner’s team isn’t sure if jeans companies will find it easy or affordable to switch to this method. It costs a little bit more — just seven cents extra per pair of jeans — to use the enzyme for dyeing. But Welner believes it’s worth it because it’s much better for the environment.
1. Why was synthetic indigo created in the 20th century?A.It made jeans’ color unique. | B.It was easy to dye cloth with it. |
C.People liked jeans made from it. | D.People were in greater need of jeans. |
A.Troubling. | B.Entering. | C.Destroying. | D.Defeating. |
A.The colour is more beautiful than the synthetic indigo. |
B.The market can keep stable goods supplies. |
C.Enzyme facilitates the advance of science. |
D.The dye is more environmentally friendly. |
A.Production costs. | B.Environmental benefits. |
C.Water consumption. | D.Laborer shortage. |
【推荐1】The term “culture” now is more used to describe everything from the fine arts to the outlook of a business group or a sports team. In its original sense, however, culture includes all identifying aspects of a racial group, nation, or empire; its physical environment, history and traditions, its social rules and economic structure, and its religious beliefs and arts.
The central beliefs and customs of a group are handed down from one generation to another. It is for this reason that most people regard culture as learned rather than innate. People acquire a culture because they are not born with one. The process by which a person develops a taste for regional foods, accented speech, or an outlook on the world over time, therefore, is known as enculturation.
Cultures are often identified by their symbols-images that are familiar and coated with meaning. Totem poles carved with animals and creative figures suggest aspects of the Native American peoples of the Pacific Northwest but more literally represent specific tribes. In Asia and India, the colour of yellow is connected with temples, while in ancient China it was a colour only the emperor’s family was allowed to wear. Thus, different cultures may respond to a symbol quite differently. For example, to some a flag may represent pride, historical accomplishments, or ideals; to others, however, it can mean danger or oppression.
To individuals unfamiliar with cultures outside their own, the beliefs, behaviours, and artistic expression of other groups can seem strange and even threatening. A society that ranks all other cultures against its own standards is considered to be ethnocentric(from the Greek ethnos, meaning “people”, and kentros, meaning “centre”). A strongly ethnocentric society assumes also that what is different from its own culture is likely to be inferior and, possibly, wrong or evil.
All people are ethnocentric to some degree, and some aspects of ethnocentrism, such as national pride, contribute to a well-functioning society. An appreciation for one’s own culture, however, does not prevent acceptance and respect for another culture. History documents the long-term vigour and success of multicultural groups in which people from numerous and various cultural backgrounds live and work together. Extreme ethnocentrism, in contrast, can lead to racism-the belief that it is race and racial origin that account for variations in human character or ability and that one’s own race is superior to all others.
1. What does the underlined word “innate” in paragraph 2 most probably mean?A.Instinctive. | B.Developed. | C.Believable. | D.Cultivated. |
A.Different interpretations of a symbol help to distinguish one culture from another. |
B.An ethnocentric country opens welcoming arms to cultures different from its own. |
C.Culture consists of some positive features of a racial group, nation or empire. |
D.People from various cultural backgrounds often reach an agreement on some image. |
A.All aspects of ethnocentrism can produce negative effects on a society. |
B.Racism is unlikely to bring about serious conflicts among different cultures. |
C.Respect and acceptance of different cultures are a proper cultural attitude. |
D.Countries with a strong sense of national pride play a superior role in the world. |
A.Culture, the Origin of Racial Superiority | B.Culture, a Faithful Mirror of History |
C.Culture, the Vigour of World Development | D.Culture, a Distinctive Identity of a Nation |
【推荐2】Don’t you have time for reading? If you are interested in non-fiction books, here are some good choices for you.
A Room of One’s Own
This essay by English writer Virginia Woolf is based on several lectures given to two women’s colleges at Cambridge University in 1928. In the essay, Woolf describes that it’s circumstance not talent alone, that allows men to be more successful at writing. Women, in other words, spend so much time cooking, cleaning, and tending to their children that they have no time left for art. To write well, therefore, a woman must have a “room of her own”. While on its surface, this essay appears to be only about writing, it is actually about wealth and class, freedom and confinement, and the power struggle between sexes.
The Art of War
Written by ancient Chinese warrior Sun Tzu, The Art of War is widely considered to be one of the best books about military strategies in human history. Consisting of 13 chapters, each dealing with a separate aspect about how to fight a war, the book has been translated into every major language and has thousands of editions. For centuries, it has been used to train world leaders for its detailed study of military strategies and effective leadership.
Letter to My Daughter
This book of essays by Maya Angelou, a respectable African-American poet, is written for “the daughter she never had” — the millions of women, both young and old, that she considers to be her “family”. From the viewpoint of a caring, older relative, this book contains lessons selected from her own life experiences, including the birth of her only child, a son, as well as the development and loss of friendship.
A Brief History of Time
If you’re short of time, then why not read about, well, the creation of time? This book, first published in 1998 from brilliant scientist and mathematician Stephen Hawking, explores mind-bending questions about the creation of the universe, including if and when it will end, and if so, how. Despite its heavy subject matter, Hawking addresses these questions in a way that’s easy to understand, even for those who know little about physics.
1. What can we learn about the four books?A.A Brief History of Time mainly focuses on the matter of time. |
B.Letter to My Daughter is actually a common family letter. |
C.The Art of War gives advice on how to be a world leader. |
D.A Room of One’s Own is more than about writing. |
A.As a physicist,Hawking is equally famous in writing. |
B.Maya devotes herself to fighting for women’s rights. |
C.The book by Sun Tzu is helpful in policy-making. |
D.Woolf looks down upon men in writing. |
A.To make comparisons among the four books. |
B.To recommend the four books to readers. |
C.To make comments on the four books. |
D.To promote sales of the four books. |
【推荐3】“We said no to the invitation to the birthday party because my child says they're not even friends.”
When I read the above words, I felt heartache.
I know birthday parties can be like a trouble, but let's believe the parents who sent that invitation weren't trying to get more gifts for their kids or make things more complicated(复杂的) .
For some kids, managing school and friends is easy. Maybe you have a child who's outgoing, selfconfident or maybe you have a child who doesn't have any problems. However, for some kids, school and friends can be very difficult.
A birthday party is a fun, exciting and good opportunity. It is a chance for the kid on the sidelines to play with other kids who don't play with him/her at school or who don't call him/her a friend.
Sometimes even when the birthday party and the theme have been decided on and the difficult decision about whom to invite has been made, there can still be doubts. Those invitations can stay untouched in the bottom of the child's backpack for days, because he/she is too scared to hand them out.
I don't know your child, and I don't know you. I do know there are parents who lie awake at night wondering if their child will have the courage to hand out the invitations in the morning; I do know there are parents who hope they can depend on other parents to teach their children to be kind enough to show up. Maybe you'll never have to be one of the parents who find it hard. I know what that's like, because I have children who find it easy. But I also have a child who doesn't. And because of that, we've become a family that says yes to every invitation we receive.
Sometimes a birthday party invitation is not just a birthday party invitation; it's also an invitation to be a friend.
1. What's the author's attitude toward the words in Para.1?A.Worried. | B.Sad. |
C.Interested. | D.Excited. |
A.Children are very different from each other. |
B.Some children at school need special attention. |
C.Children should be encouraged to play games. |
D.Not all children can deal with school problems well. |
A.A chance to have some fun outdoors. | B.A chance to get many gifts from others. |
C.A chance to play and make friends with others. | D.A chance to invite other children to their homes. |
A.Kids really love going to parties. | B.Kids should learn to make friends. |
C.Some kids aren't good at making friends. | D.We'd better accept birthday party invitations. |
【推荐1】Crackle is a website that lets you stream free movies and watch free TV shows on your computer, phone, and tablet. Although you'll need to sit through a few commercial breaks during the movies and shows, an awesome selection of programming, as well as a decent video quality, will have you coming back again and again.
View Crackle's Free Movies
Movies at Crackle are organized into types to help you find thrillers, comedies, action movies, Crackle original movies, dramas, crime movies, horror films, and more. You can sort the free movies alphabetically or by recently added so you can check back as often as you want to see what they've been including in their free selection.
Crackle regularly has around 100 free, full-length movies that you watch any time you want. New movies are constantly being added and retired from Crackle, so you'll always find something new to watch.
View Crackle's Free TV Shows
Like the movies section, the TV shows you can find here include many types of programs and original Crackle series that you can't find anywhere else. Crackle keeps videos during a particular time and then removes them. This means if you watch part of a movie one day, it's quite possible that it could be gone the next before you can finish it.
How to Stream Crackle Movies & TV Shows
Crackle works on lots of devices. You can follow the links above to see the movies and TV shows on your computer, but there's also a Crackle movie app so that you can stream the videos on your phone or tablet. You can download the Crackle mobile app on iOS devices, Android phones and tablets, and other devices.
1. What can be learned about Crackle from the first paragraph?A.It inserts several advertisements during films. |
B.It attracts more viewers due to its web design. |
C.It charges viewers fees to enjoy all its programs. |
D.It requires viewers to download programs to watch. |
A.They are all produced by Crackle. | B.They are classified by time. |
C.They are easy to find and appreciate. | D.They are kept on Crackle all the time. |
A.An announcement. | B.An advertisement. |
C.An art works review. | D.An official report. |
【推荐2】If you are one of those who think exercise is a waste of time and of no benefit at all to the body, you might have to have a rethink.
Regular physical activity can help protect from some health problems. For instance, exercise controls weight. For the obese (肥胖的),exercise is very important as it helps reduce body fat by building or preserving muscle mass and improving the body's ability to use calories. When you engage in physical activity, you burn calories. The more intense the activity is, the more calories you burn. When exercise is combined with proper nutrition, it can help control weight and prevent obesity, a major risk factor for many diseases. Besides workouts at the gym, your body can benefit from other forms of exercise such as jogging, fast walking, running, playing games.
Regular physical activity can improve your mood and the way you feel about yourself. Need an emotional lift or need to blow off some steam after a stressful day? A workout at the gym or a quick 30-minute walk can help. Exercise stimulates various brain chemicals that may leave you feeling happier and more relaxed. You may also feel better about your appearance and yourself when you exercise regularly, which can boost your confidence and improve your self-esteem. Exercise gives you a chance to enjoy the outdoors or simply engage in activities that make you happy.
Regular physical activity is a great way to feel better, gain health benefits and have fun. As a general goal, aim for at least 30 minutes of physical activity every day. If you want to lose weight or meet specific fitness goals, you may need to exercise more. Remember to check with your doctor before starting a new exercise program, especially if you haven't exercised for a long time, have chronic health problems, or you have any concerns.
1. How does exercise help the overweight people?A.It reduces their appetite. |
B.It works muscles and burns calories. |
C.It contributes to absorbing proper nutrition. |
D.It contains a wide range of forms functioning differently. |
A.Exercise is likely to reduce depression. |
B.Outdoor activities benefit people's appearance. |
C.A 30-minute walk every day can help lose weight. |
D.Exercise can create some relaxing brain chemicals. |
A.Getting the doctor's opinions. | B.Setting some fitness goals. |
C.Clearing up the concerns. | D.Having a medical checkup. |
A.Exercise can consume too much time. |
B.Nutrition and exercise are equally important. |
C.You can benefit more from outdoor activities. |
D.Regular exercise can improve one's overall quality of life. |
【推荐3】The place of exposure to the greatest amount of allergen(过敏原)for the longest time is in the bedroom. Up to 60% of the dust mites(螨虫)found in the home are actually living in your bed and you spend about one-third of your life in the bedroom! And, bedrooms are the easiest area to control as an allergen free zone. Your cleaning professional will first vacuum the mattress(垫子), carpeting and furniture using a vacuum cleaner.
The mattress is then thoroughly cleaned on all surfaces using the Responsible Care cleaning agents and a special low moisture cleaning tool designed to leave the mattress as dry as possible. Following cleaning, Allergy Relief Treatment is applied to all mattress surfaces using a fine mist application. The mattress is then placed in a drying position and a special air mover used to speed the drying process, which, depending upon temperature and humidity, normally takes about an hour.
The same safe cleaning agents are used to clean the bedroom carpeting and if desired, any furniture or rugs. This is also followed by an application of Allergy Relief Treatment. Once again, a speed drying system is set up to dry the cleaned items as quickly as possible and bring the humidity down to normal levels. Baseboards and windowsills are cleaned as well. While the cleaning and treatment service is being performed it is highly recommended that the bedding and pillows be washed in hot water and that two cups of Allergy Relief Treatment be added to the washing cycle.
While servicing the bedroom is the highest priority(优先), significant benefits may also result from cleaning and treating other areas where allergy sufferers spend lots of time. These areas include the furniture and carpeting in rooms where time is spent watching television, reading and so on. Also, carpeted areas that pets have access to should be cleaned and treated.
A test for the presence of dust mites in quantities requiring treatment is also available from our company. But we will only test dust mites and will not provide information on pet allergen.
1. Which place has the most dust mites in your room?A.Bed. | B.Carpet. |
C.Furniture. | D.Floor. |
A.The use of cleaning agents. |
B.The surfaces of mattress. |
C.Cleaning the mattress. |
D.Drying the mattress. |
A.It is a cure to allergy. |
B.It is a tool to kill mites. |
C.It is the name of a company. |
D.It is a chemical to prevent allergy. |
A.A magazine about furniture. |
B.The website of a cleaning company. |
C.The website of a hospital. |
D.A newspaper on public health. |