1 . Over the last decades, we have witnessed an ever-increasing use of electronic devices, leading in turn to electronic waste (e-waste) becoming the world’s fastest growing waste stream. In 2019, a total of 53.6 Mt of e-waste was generated globally, only 17 percent of which is documented as having been managed in an environmentally sound manner, which has been pushing researchers to address the e-waste problem.
Now researchers at the Cellulose & Wood Materials Laboratory have crafted a water-activated disposable (一次性的) battery made of paper and other environmentally friendly materials.
The new paper battery has the same key components as traditional standard batteries. Like a traditional chemical battery, it has a positively charged side called a cathode, a negatively charged side called an anode and a conductive material called an electrolyte between the two. Instead, in the new battery, the anode and cathode are inks printed onto the front and back of a piece of paper. That paper is filled with salt. It will dissolve when you add just a couple of drops of water to the paper. The resulting saltwater solution acts as the electrolyte, which allows electrons to flow. About 20 seconds later, the battery will produce a stable 1.2 volts of electricity until the paper dries out. (For comparison, a standard AA battery provides 1.5 volts.)
The researchers demonstrated that their battery could present a sustainable alternative to the more harmful batteries that are common in low-power devices, such as an alarm clock. Nyström, head of the research, even pictures a bright future where these batteries are applied to diagnostic tests in hospitals and environmental sensors, ideally with other sustainable components such as screens and packaging. “That future may not be so far off.” Nyström said hopefully.
It is hard to predict a time line for producing such items on a large scale, but Nyström says he is in contact with potential industry partners and believes these batteries could make their way into products within the next two to five years.
1. What can we learn from paragraph 1?| A．Electronic devices are overly used. |
| B．Electronic devices are the main source of waste. |
| C．Electronic waste has become a global problem. |
| D．Electronic waste is mostly managed in a sound way. |
| A．The salt. | B．The paper. | C．The battery. | D．The ink. |
| A．It has come into the market. |
| B．It can power common electrical equipment. |
| C．It has the same anode and cathode as the traditional battery. |
| D．It stops producing electricity when the saltwater solution dries out. |
| A．Indifferent. | B．Positive. | C．Negative. | D．Doubtful. |
2 . Tulum’s location on Mexico’s Caribbean coast, in the Riviera Maya, makes it an ideal spot for enjoying beautiful beaches and great weather.
Spring
Spring is a popular travel time throughout Mexico. Many Mexican families go on vacation during this time, so you should make your accommodation reservations in advance if traveling during this period.
Event: Holy Week
For many Mexicans, it’s an opportunity to head to the beach.
Summer
Summers can be hot and cloudy. There are far fewer tourists during this time, which is great for photo opportunities as well as for enjoying the destination without the crowds. Summertime is the best time to observe whale sharks and sea turtles.
Event: Talking Cross
The Celebration is held in the month of July and has its origins in the 1800s.
Fall
You’re likely to experience some rain if you visit during this season. The rainy season is not completely uncomfortable, however. It usually only rains for a short time, and then the sun comes out again.
Event: Sea Turtle Festival
It is a festival for sea turtles in order to raise people’s consciousness of protecting sea turtles.
Winter
Winter offers the best weather in Tulum. If you’re looking for sunny days and near-perfect beach conditions, this is the time to visit. However, there are more crowds December and January are busy travel months, and Tulum’s party scene and nightlife are at a peak.
Event: Tulum Food, Spirits & Wine
It is a 6-day restaurant week featuring music and special meals and wine. Tourists enjoy a fun and creative cultural environment.
1. What are you advised to do before visiting Tulum in spring?| A．Buy a raincoat. | B．went a surfboard. |
| C．Prepare food for whale sharks. | D．Book hotels ahead. |
| A．Holy Week. | B．Sea Turtle Festival. |
| C．Tulum Food, Spirits & Wine. | D．Talking Cross. |
| A．In spring. | B．In summer. | C．In fall. | D．In winter. |
