2 . From airplanes to apartments, most spaces are now designed with sound-absorbing materials that help decrease various sounds of everyday life. But most of the sound-absorbing materials that can cancel out human voices, traffic noise and music are made from plastic foams (泡沫) that aren’t easily recycled or degraded. Now, researchers reporting in ACS Sustainable Chemistry & Engineering have created a biodegradable film (薄膜) obtained from seaweed, which effectively absorbs sounds in this range.

Controlling and optimizing the way sound moves throughout a room is the key to creating functional spaces. Foam sound-absorbing panels are a common solution, and they come in a variety of materials and thicknesses tailored to specific sound requirements. Most of these foams, however, are made from a type of plastic material and other chemical substances that are obtained from natural oil or petrol. To avoid petrochemicals, researchers have explored more renewable sources and biodegradable sound-absorbing alternatives. But many current options are made from plant fibers that don’t effectively decrease noises in the most useful range of sound frequencies, or they are too thick or difficult to produce. So, Chindam’s team wanted to develop a biodegradable material from a plant, which would be simple to produce and could absorb a range of sounds.

The team created films of agar (琼脂), a material that comes from seaweed, along with other additives developed from plants and varied the thickness of the films. After running the materials through a battery of tests, the researchers measured how well the films reduced sound across a range of frequencies. To do this, the team created a sound tube in which a speaker is placed at one end, and the test film is fitted over the other end. Microphones in the middle of the tube measured the amount of sound sent by the speaker and the amount of sound reflected off the film. These experiments showed that the films with many small holes made with the highest concentrations of agar had the greatest sound-absorbing qualities and performed similarly to traditional sound-absorbing foams. The researchers plan to explore ways to change the agar films to give them other desirable properties, such as flame resistance, and will explore other biologically obtained film materials.

3 . We have scenic beauty all around us, but looking around, much of it is covered with food packages, plastic bottles, and other rubbish. Despite warning signs and boards that constantly say “No littering here!”, people are unwilling to understand the significance of keeping public places clean. However, Khao Yai National Park in Thailand has taken an unusual step to make sure tourists clean up their own trash.

The park has begun sending trash back to the litterbugs (乱扔垃圾者) with a polite note saying “You forgot these things at Khao Yai National Park” to remind people that littering in public places is against the rules. Mr. Varawut Silpa-archa, minister of Natural Resources and Environment of Thailand, posted a series of pictures on Facebook related with the new step. He posted a picture of a trash-filled box that was ready to be shipped with the words—“YOUR TRASH—WE’LL SEND IT BACK TO YOU.”

Varawut explained that throwing about trash could endanger wild animals, which might eat it by mistake when searching for food. He said littering in the park could carry a fine of up to 500,000 Thai Baht (about $16,000 U.S. dollars), a prison sentence of up to five years, or both. And the offending (违法的) visitors will also be banned from returning to the park.

The officials matched the trash to its owners by taking address details from the camping equipment rental forms. To make the process easier, people will be allowed to enter the park only after writing down their address.

“We think Khao Yai National Park’s new step has made a great contribution to maintaining our country’s natural resources,” Charinya Kiatlapnachai, director of the tourism authority of Thailand, told The Washington Post. “This gesture is an effective way to ensure we all do our part to help our country remain clean, safe and beautiful.”

6 . I'm from a fishing family. My grandfather was a fisherman, working out of Fano, the Italian town where I grew up and still live. I work from 7 p.m. until 11 a. m. with fishermen on the north Adriatic Sea. There are only six or so of us on board. At night, the fish are most active and we can avoid other ships.

The nets reach the sea bed for the catch but sometimes they also catch turtles that often die in the nets or on board. The net is designed to allow turtles to escapes it has a hole at the top they can swim out of. We call it “TED”. The TED aims at reducing the bycatch (误捕) of turtles. Turtles and some larger fish can leave through the TED, but the current (水流) holds most of the catch in the net.

I ensure that the net is working, and that the fishermen we're cooperating with can still catch enough for their livelihoods while protecting turtles. The work is part of research by the Cetacea Foundation, in cooperation with University of Pisa, where I'm a field researcher. It is financed by the LIFE programmer. I love this work. It means I'm not stuck in an office all day and instead can enjoy the ocean and work closely with people who live by the sea.

When my grandfather was fishing in the 1970s, there were more fish and more turtles around. At the foundation, we save 50-60 turtles a year, most of which are harmed because of fishing. If we can protect turtles by popularizing this device to fishermen all across the Adriatic, I'd see this work as a success.

7 . I went for a walk up to a local park and Chester was running about. Suddenly, two dogs appeared, attacking him. He got _________ and ran off in an unfamiliar direction. I can only _________ myself-it’s like losing a family member. My daughter didn’t sleep for three days. She just thought her pet was _________.

My family had almost lost _________ until Erica decided to offer her services. She uses a drone(无人机)to help find lost dogs. Equipped with a hi-tech thermal imaging(热成像)camera, the drone can detect heat _________ from 250 feet in the air. _________, when asked to help out in a search for a _________, Erica simply turns up to the dog’s last known _________ and sets up the drone. Having found more than 160 dogs, it’s proved pretty _________.

And it’s easy to see why. Can you __________ Chester running around these woods? To the naked eye(肉眼), it’s virtually impossible, but pop the thermal image up and he jumps out, __________ his owner to bring him safely back home.

Having saved hundreds of dogs, the method is clearly __________. Erica doesn’t __________ for her services and instead does it for the pleasure of seeing the owners __________.

Erica’s drone has helped create countless happy __________ and is sure to make many more in the future.

8 . The worsening air quality in tropical(热带的) cities is causing ever greater threats to people’s health and this trend will only get worse as the urbanization(城市化) is progressing quickly, scientists have warned. In a newly published study, a team of researchers explain that across all the 46 cities they surveyed from Africa to Asia, they have measured significant annual increases in pollutants harmful to health.

This trend is troubling as tropical cities usually lack proper air pollution monitoring measures and policies to deal with the problem. “These cities are predicted to reach populations of up to 80 million people by 2100, so actions targeting human-related pollution are badly needed,” the scientists stress.

Already the number of people dying prematurely(过早地) from long exposure to air pollution has been on the increase and people living in cities in South Asia are the worst affected. In Dhaka, Bangladesh, some 24, 000 people die of such causes each year while around 100, 000 people die in Indian cities such as Mumbai, Bangalore etc.

“The number of deaths in tropical cities in Africa is still lower due to recent improvements in health care there. But the worst effects of air pollution on health will likely occur in the coming decades,” the scientists say.

The reasons for worsening air quality in tropical cities lie in increasing road traffic, waste burning, and the widespread use of coal and wood. Industry is also partly to blame. “Open burning for land clearance in the past contributed most to air pollution in the tropics,” explains Karn Vohra, an author of the study. “Our analysis suggests we’re entering a new age when some cities experience rates of air pollution in a year that others experience in a decade,” Vohra warns.

In southern China, there is a famous road     1    (build) across Poyang Lake, which lies in the north of Jiangxi Province, China and is known as China’s second     2     (large) lake. People in China also call it “the most beautiful road under the water.”

This road is sure     3     (attract) a lot of attention towards the end of May every year. A lot of people come out of     4     (curious). The water level of the lake is so close to the surface of the road,     5     makes the view ahead broad and bright when people drive along. It’s as though they were taking a boat across the lake. The feeling is     6     (simple) wonderful!

For the next few months, this road is not above the surface    7    under the water. When the water level of Poyang Lake starts to go up, the road surface becomes unseen. However, drivers can still drive across the lake safely     8     watching the guardrails(防撞护栏) fixed on either side of the road. For thrill-seeking motorists, it’s like     9     (drive) an amphibious(水陆两栖的) super car. Then in a few days, the entire road     10     (flood) with the continuously rising water. A few months later, the road will reappear.