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Most air conditioners and fridges rely on contracting and expanding a liquid to either absorb or release large quantities of heat. While these systems are relatively cheap and simple to produce, they aren't very efficient and require lots of energy. Besides, many of the coolants （冷却剂） used are environmentally harmful.

Now, Emmanuel Defay at the Luxembourg Institute of Science and Technology and his colleagues have developed a coolant-free refrigeration device made from the metals lead, scandium（钪） and tantalum（钼）. It can reach maximum efficiencies of more than 60%, almost double that of typical single-room air conditioning units. The technology is based on a principle called electrocaloric cooling, in which an electric field applied across a material changes the direction of electric charges, causing a temporary increase in temperature and a succeeding decrease when the electric field is removed.

To make their cooling system, Defay and his colleagues piled up eight strips of the material known as lead scandium tantalate, which is electrocaloric, on top of one another and dipped them in a heat-carrying liquid, silicone oil. When an electric field is switched on and the strips heat up, the liquid moves to the right, and when it cools down, it moves to the left, creating permanent regions of hot and cold of about 20℃difference. These regions can be used as hot and cold reservoirs from which the oil can be circulated through pipes to cool or heat rooms or objects as desired.

"Although the efficiency of the device is theoretically 67%, the efficiency of the current design is around 12%. This could be improved if a better conductor of heat than the lead scandium tantalate were found," said Defay.

"A highest performance has been achieved by combining known elements," said NeilMathur at the University of Cambridge. However, he added, the team only looked at the cooling power of the pile of metal strips themselves, while it would be interesting to see how the entire device performs together.

A self-described "girly girl", nine-year-old Zandra Cunningham was constantly begging her parents for the latest beauty products. One day her dad simply told her "no", which inspired her to make her own.

Zandra has been recognized by Entrepreneur magazine as one of the youngest millionaires in America. When asked about her experience as a child entrepreneur（企业家）, Zandra says, "It wasn't frightening. When you're young, you don't have that fear mentality. ‘Maybe it's not going to work' never really crossed my mind." For Zandra, it became a challenge to separate her personal interest from what her customers actually wanted. "There were a lot of things that I felt were good ideas, but they wouldn't fit into the market," she says. Being part of the market herself, Zandra felt she had a unique perspective that allowed her to truly listen and respond to her customers.

It started as a hobby for Zandra and her mom. They'd play around with different ingredients until they found formulas they liked "through trial and error". Slowly, they started transforming the pastime into a brand. Zandra began selling her products at local markets, and a few years later—when Zandra was 12 years old—the family started a shop for Zandra Beauty. At the time, Zandra Beauty was one of the first brands to offer plant-based and organic beauty products at an affordable price. The 21-year-old has essentially grown up alongside her brand—but her goals have remained the same: "Our main focus is to push out amazing products that are safe for everyone and the earth."

"There're so many brands doing similar things, but there's still so much room to grow," says Zandra. "Your customers are out there, and you just have to find something that's going to set you apart."

Suspension bridges, with their high towers and elegant spans（跨度）, are achievements of engineering. This list covers the longest main spans of suspension bridges around the world, not longest total lengths, as those main central spans are where the real engineering magic happens.

Osman Gazi Bridge, Türkiye

The Osman Gazi Bridge is a splendid suspension bridge. The bridge was finished on July 1, 2016, and at the time, it was the longest suspension bridge in Türkiye and the fourth longest in the world by the length of its main central span, which measures 1,550 meters. It reduced travel time between Istanbul and Izmir from six hours to around five.

Great Belt Bridge, Denmark

The Great Belt Bridge connects the Danish islands Zealand and Funen. The suspension bridge has a total length of 6,790 meters and a main central span of 1,624 meters, making it the world's sixth longest main span—for now. It enabled a direct driving route from mainland Europe to Sweden through Denmark.

1915 Çanakkale Bridge, Türkiye

The bridge's construction, which began in March 2017 and concluded in March 2022, was ambitious from the get-go. Spanning the historic Dardanelles Strait in northwestern Türkiye, the 1915 Canakkale Bridge is a symbol of national pride. Officially the world's longest suspension bridge, it stretches a remarkable 2,023 meters in its main central span.

Yangsigang Yangtze River Bridge, China

Opened to traffic in October 2019, the Yangsigang Yangtze River Bridge in Wuhan, Hubei Province, China, is the longest suspension bridge in China and the third longest suspension in the world. It spans 1,700 meters across the famous Yangtze River. The bridge notably has the world's longest double-level bridge span, accommodating various forms of transportation on its two levels.

Crash! The old black pickup truck in front of me stopped. I didn't. I crashed into its back breaking the fender（挡泥板） and bending the driver's door of my car. To make matters worse. it wasn't my car. It was my father's. I shouldn't have been driving it, and now I had destroyed it.

A farmer jumped out of the truck, slowly and carefully, and looked at the damage. I sat sobbing（抽查）， my lip bleeding where I'd bitten it. He was in a hurry to leave, but we managed to exchange names and phone numbers before he pulled out onto the highway again. I followed. knowing I dared not go home. I'd be in big trouble.

It was my high school graduation day. I drove to school and climbed out through the passenger door. Surveying the broken fender and the door, tears flowed down my face, which was rapidly becoming swollen. I walked into the gym and joined my classmates to prepare for the graduation party. Bad news traveled fast, and soon a teacher came to me.

"You'll have to go home to get dressed for the graduation sooner or later," she said. "Sooner would be much better and you have to tell your parents."

I finally agreed and slowly drove home. The Death March sounded in my ears.

My mother took one look at my face when I got home and screamed, "What on earth happened?"

I hung my head and tears rolled down my face again. "I crashed Daddy's car."

She threw up her hands in panic and rushed to the backyard where Dad was making burgers.

"Stop cooking, Ted. We're not going to cat. Jean has destroyed your car."

Dad looked at her and said quickly. "Is she hurt?"

"No, except for biting her lip."

"Well, then, what does that have to do with cating dinner?" He put a burger on a plate with the others, then walked across the yard and put his arm around me. "Let's go inside and hear all about this if you're sure you're all right." I sobbed and nodded.

注意：1. 续写词数应为 150 左右；2.请按如下格式在答题卡的相应位置作答。

The phone was ringing when we got to the back door.

……

I graduated that evening with my family in attendance.

The Leshan Giant Buddha（乐山大佛） is a huge statue(carve) into the side of Lingyun Mountain. Sichuan Province. It is the tallest and (large) Buddha in the world. There is a local (say):"The mountain is a Buddha and the Buddha is a mountain."If you want to get close-up view of the Buddha, you have to climb the mountain. You can choose the walking route, going along the wooden pathways (enjoy) the changing view from various (angle) of the Buddha, from its foot to its head. It (take) around two hours. You can also choose to visit the Leshan Giant Buddha on a sightseeing boat. This will let you se c the Buddha from a distance get a full look at it. taking only thirty minutes.

However, I bet you`ll just be many other visitors — doing both the boat ride and the two-hour walk. Only when you join the walking tour up, down, around and even through the rocks will you feelincredible the place is. Believe me, it's well worth it.

The polar bear was a tiny point in a frozen white world. A film crew began to follow at a distance, gradually getting1 , hoping to get a good picture. However, the bear came to a rest at a hole in the ice and started to2 . So did the crew.

For 12 hours the bear lay half asleep, half3 without a move. It was too long; the crew had been working for 22 hours 4 on the sea ice. Cold and exhausted, they 5 defeat.

Hours of waiting for little reward is not 6 ."It's the price we pay to get unique images," says award-winning photographer Florian Ledoux. "It is a 7 for us to get each shot in Arctic — we push our limits." The battle is intense especially during winter:8  dark ness affects your mood, the lack of routine9 your body clock, you are forever fighting the bitter cold, and everything you touch with 10 hands sticks to your skin. However 11 your clothes are, the cold bites through.

An Arctic photographer for years, Ledoux has witnessed the significant 12 there. It is heating up, causing ice to melt and 13 the whole ecosystem. "Am I just photographing? No," he says. "I try to catch some unique beauty of 14 , to give a voice to the one that cannot 15 ."

In 2001, UNESCO declared 21 May as UN World Day for Cultural Diversity for Dialogue and Development. The day's not intended to find out the uniqueness of different cultures, separating them from each other.Here are a few modest and simple ways to mark the occasion.

Visiting an exhibition or a museum dedicated to other cultures comes first since it may inspire you to create something yourself, and heighten your desire to learn about a new topic or culture.. T or example, you can see the British Museum's collection online, and the National Gallery has a ɑ:gital tour of 18 rooms that lets you get up close to the paintings.

 It's a great way to expand your knowledge of the world. Many traditional folk tales have universal themes, but at the same time, shine a light on particular aspects of another culture. So now might be a great time to dive into the storybooks and read folk tales.

There is perhaps no better way to experience another culture than listening to music. Even if you don't understand the words, you can still hear the influence of other cultures. You could allow yourself to discover music from every corner of the globe , on forums.After all, series of musics are on the air, often with strong international influences.

It never goes without mentioning language while embracing culture diversity. It is relatively easy to have a go at trying a new language through the many smartphone apps or through an online language exchange.

A. Or you could listen to radio programmes.

B. In short, it's never too late to learn a language.

C. You could also appreciate music in foreign films.

D. Remember language serves as a reflection and carrier of culture.

E Learning about traditional stories from other cultures won't disappoint you.

F Even if you can't visit a museum at first hand, you can select virtual exhibitions.

G. Instead, it's a chance to unfold the similarities and celebrate the cultural diversity.

Let's face it. You're likely reading this article in an effort to avoid some other tasks you're procrastinating （拖延） to learn how to stop procrastination, but the clock is ticking. So why can't you seem to get rid of that?

Though the psychological causes are still debated, there's a human tendency to over or underestimate the value of a reward based on its temporal proximity（时间接近）. This is often referred to as temporal discounting. For example, if I offered you $100 today or 110 in a month, most would take the hundred and run. But what if instead I offered you 100 dollars in a year or 110 in a year and one month, you might say to yourself if I can wait a year I can wait the extra month.

But the time and value difference are the exact same in each example. It. turns out that human motivation is highly influenced by how near the reward is meaning the further away the reward is the more you discount its value. So being online is more appealing than preparing for your test. The problem is surfing the Internet provides many small quick and continuous rewards unlike your test scores which are a future one.

So how do you overcome the urge to put off so many tasks?

Unfortunately there is no definite answer, but try rewarding yourself with a timely snack or other enjoyable activities. The Pomodoro Technique makes use of a timer to work for 25 minutes straight and when you've done this give yourself the reward with a 5-minute break. Then start the working clock again, Gradually increasing the amount of work time you put in will improve your time management skills.

It's been shown that creating a costly deadline is also an effective way to manage your working habits. And try to enjoy the process of achieving something instead of thinking only our minutes of suffering.

Today China is the world's biggest consumer of wheat. But it wasn't always that way.

Wheat only came to the area now known as northern China toward the end of the Neolithic（新石器） period, some 4,600 years ago. Initially, w heat didn't seem to be so delicious and had been treated as a crop of desperation rather than a cooking delight. The first farmers of northern China primarily grew millet（粟）， starting as early as 11,500~years ago. By the time of the Tang dynasty, w heat had replaced millet, becoming a major crop. But relatively little was known about exactly why this shift occurred.

In an attempt to track the answer, I accumulated（积累）a collection of nearly 1,200 data points covering more than 50 sites from the mid-Neolithic, about 9,000 years ago, to the collapse of the Eastern Han dynasty in 220 AD. The sites were across 8 modern provinces, ranging from Gansu province in the northwest to Shandong province in the east.

One possible explanation is a major climate shift, called the Holocene Event 3, which happened 4,000 to 4,500 years ago. At that time, the climate became colder and drier across continents, causing damage to crop production.

On top of this, the late Neolithic period was also a time of rapid population growth around the world. With an ever-increasing population and unsteady crop production, it is reasonable to assume that Neolithic farmers in northern China were struggling.

Wheat, it turns out, actually needs more water than millet, making it seem a poor choice for a dry period of history. But importantly, it can be sowed after millet has been harvested. That, we think, is the most likely reason why the people across northern China started to grow wheat.

From more extreme weather to changing coastlines, climate change has always brought unexpected and sometimes dramatic changes to societies. In this instance, the consequence of the Holocene Event 3 in northern China proved, eventually, delicious.