1 . The Mona Lisa is the famous Leonardo da Vinci painting of a woman with a mysterious smile. This week, the painting gave up a secret.
Scientists using X-rays to examine the chemical structure of a small part of the painting discovered a technique Leonardo used in the work. An oil paint used for it was a special, new chemical mixture, which suggests that the Italian artist was in an experimental mood when he worked on the painting in the 16th century.
“He loved to experiment, and each of his paintings is completely different technically,”said Victor Gonzalez, a chemist who has studied the chemical element (成分) of several works by Leonardo and other artists. The researchers found a rare lead compound (铅化合物) — plumbonacrite, in Leonardo’s first layer of paint. The discovery proved that da Vinci most likely used lead oxide to thicken and help dry his paint. The paint in the study is about the thickness of a human hair, lying in the top right area of the painting.
The scientists looked into its atomic structure using X-rays, moving particles at the speed of light, permitting researchers to look deeper into the paint structure. “ Plumbonacrite is really a fingerprint of his recipe, as it’s the first time we can chemically confirm it,” Gonzalez said.
Dutch artist Rembrandt may have used a similar mixture when he was painting in the 17th century. Gonzalez and other researchers have found plumbonacrite in his work, too. Leonardo is thought to have put lead oxide powder, which has an orange color, in the oil to make it thicker and dry faster. “What you will get is an oil that has a very nice golden color,” Gonzalez said. “It flows more like honey.”
But the Mona Lisa — said by the Louvre to be a portrait (肖像) of Lisa Gherardini, the wife of a Florentine silk businessman — and additional works by Leonardo still have other secrets to tell. “What we are saying is just a little brick in the knowledge,” Gonzalez said.
1. What’s the new discovery about the Mona Lisa?| A．A new explanation of the secret smile. |
| B．A new chemical element used in the painting. |
| C．The secret of the woman in the painting. |
| D．The structure of the paint da Vinci used. |
| A．Open secret. | B．Widespread use. | C．Hidden element. | D．Long-term dream. |
| A．It helps to make many things into paints. |
| B．It helps to make paints easy to deal with. |
| C．It helps to keep the paintings last long. |
| D．It helps to make paintings rich in color. |
| A．It has more secrets to tell the world. |
| B．It’s the portrait of a silk businessman. |
| C．It’s well kept in bricks in the Louvre. |
| D．It has a mixture of different art styles. |
2 . You improve your robot’s software by improving its software. Agrim Gupta of Stanford University, however, begs to differ. He thinks you can also improve a robot’s software by improving its hardware. He and his colleagues have invented a way of testing this idea.
They brought to their robots, unimals, the principles of evolution (进化) by natural selection. Unimals, with globes for heads and sticks for arms and legs, are software beings interacting with a virtual environment. The environments where they wandered were in three varieties: flat grounds, grounds with hills and steps, and ones that had the complexities of the second sort, but with added objects.
To begin with, the unimals were randomly assigned various shapes, but with identical software— derl. Newly created unimals learned to face the challenges in a virtual bootcamp. They were then entered into tournaments in groups. Each group winner was awarded one mutation (变异) —one extra arm or leg, or one extra turning in a joint. The new replaced the oldest unimal and then was assigned to a new group, and the process repeated. About 4,000 varieties of them underwent training.
The team were surprised by the diversity of shapes that evolved. Crucially, though, the researchers found the most successful unimals learned tasks in half the time their oldest ancestors had taken, and that those evolving in the toughest grounds were the most successful.
In this evolution of unimals’ morphology (形态) to promote the ability to learn, Dr Gupta sees a version of something called the Baldwin effect. In 1896 James Baldwin, a psychologist, argued that minds evolve to make the best use of the morphologies of the bodies. What Dr Gupta has shown, though in software, is that the opposite can also be true — changes in body morphology can improve the way minds work. Even though he held the software constant, it became more efficient at learning as the unimals’ bodies evolved.
Whether that discovery can be turned to account in the way robots are developed remains to be seen. But the way of testing is certainly an out-of-the-box idea.
1. How was the test conducted?| A．By promoting Unimals’ learning. | B．By adjusting the environments. |
| C．By proving the evolution theory. | D．By stimulating unimals’ mutation. |
| A．The number of trained unimals. | B．The decline in time for learning tasks. |
| C．The variety of evolved shapes. | D．The replacement of old unimals. |
| A．Mind evolution affects body shaping. |
| B．Body changes better mind work. |
| C．Hardware changes do not impact software. |
| D．The discovery is useful in robot development. |
| A．Negative. | B．Objective. |
| C．Indifferent. | D．Approving. |
3 . In the deepest dive in a manned submersible(潜水器), US explorer Victor Vescovo spotted and video-recorded a plastic bag and a pile of candy wrappers on the seabed.
His
Since the patent(专利) for plastics was
Most of the discarded(丢弃) plastic products
Every year, about 8 million tons of plastic waste flow into the ocean. It is
This plastic waste
We must do something to
But that’s so much
| A．report | B．discovery | C．record | D．accumulation |
| A．everywhere | B．anywhere | C．somewhere | D．nowhere |
| A．as | B．although | C．but | D．so |
| A．abolished | B．acquired | C．registered | D．advertised |
| A．with | B．without | C．off | D．above |
| A．end up | B．wake up | C．grow up | D．walk up |
| A．continent | B．park | C．island | D．garden |
| A．suggested | B．estimated | C．weighed | D．congratulated |
| A．thousand | B．hundred | C．million | D．billion |
| A．feeds | B．saves | C．cares | D．kills |
| A．looking | B．winding | C．floating | D．jumping |
| A．earth | B．air | C．water | D．environment |
| A．pollution | B．existence | C．temperature | D．cycle |
| A．production | B．supply | C．pyramid | D．trade |
| A．change | B．clean | C．satisfy | D．realize |
| A．otherwise | B．instead | C．therefore | D．meanwhile |
| A．exercise | B．activity | C．fact | D．habit |
| A．harder | B．more effective | C．more courageous | D．easier |
| A．calling for | B．looking for | C．sending for | D．waiting for |
| A．start | B．refuse | C．continue | D．hope |
4 . China's space program took a major leap recently when it successfully landed the Zhurong rover(登防车) on Mars marking the country's first landing on another planet. Teams then rolled the rove onto the Martian ground and begin a mission to search for evidence of water and signs of past life.
The touchdown makes China the second county in history to land a rover on the surface of Mars. After months in orbit around the red planet, the Tianywen-l Spacecraft released the Zhurong rover for a landing in Utopia Planitia, a vast plain that may once have been covered by an ancient Martian ocean.
“Landing safely on Mars is a huge challenge, especially for China's first soft landing attempt," said Long Xiao, a scientist at the China University of Geosciences, "But it is a necessary step for Mars and deep-space exploration."
Mars is significantly harder to land on than the moon, says Michel Blanc at the Research Institute in Astrophysics and Planetology in France. But China has had a series of successful lunar missions that prepared it for a Mars landing.
China will openly share the data from Tianwen-1 and Zhurong the same way it has shared data from its lunar exploration missions, Long says, benefiting scientists around the world.
The mission will also set the stage for China’s next planned voyage to Mars---a sample---return attempt scheduled to launch around 2028.Beyond Mars, the country has plans to launch a Jupiter probe(探测仪), including a possible landing on the moon Callisto, to collect samples from a near-Earth asteroid(小行星), and to send a pair of spacecraft toward the edges of the solar system.
“In the age of ocean exploration, China has a history of Zheng He's voyages to Southeast Asia and Africa," says Zhang Xiaoping at the Macau University of Science and Technology, referring to early 15th-century explorations. Zhang views China's Mars mission as a continuation of these Ming Dynasty journeys.
1. What can be known about the Zhurong hovers?| A．It lands in an ocean on Mars. |
| B．It provides evidence of life on Mars. |
| C．It was transported to Mars by Tianwen-1. |
| D．It marks the first human exploration on Mars. |
| A．Lunar exploration is more difficult than Mars exploration. |
| B．China made successful soft Manding attempts on Mars before. |
| C．China's latest space exploration can benefit the whole world. |
| D．Mars exploration is the significant step to prepare for lunar exploration. |
| A．The specific task of Tianwen-1. |
| B．The background of Mars exploration. |
| C．The timeline of China's lunar exploration. |
| D．The plan for China's further space exploration. |
| A．To compare him with other explorers in history. |
| B．To highlight the significance of Mars exploration. |
| C．To praise his great achievement in ocean exploration. |
| D．To inspire the readers' imagination in space exploration. |
Eating shows originated in South Korea and soon became
As a result, nowadays, when searching keywords such as “eating show” or “big stomach king” on the websites in China, what users see is a reminder that
Previously, food waste in China was a common occurrence. According to a joint report
Therefore, it's time to enhance public
After all, good food consumption habits are signs of social progress and civilization.
