【推荐1】Wood has many great characteristics that make it the perfect building material. It is cheap, durable(耐用的), easily available, and most importantly, environmentally sustainable. The one thing it is not, is transparent(透明的).Now thanks to a team of scientists at Stockholm’s KTH Royal Institute of Technology, the material may even be able to add that feature to its already impressive list.

Lead researcher Dr. Lars Berglund said he was inspired to create the transparent wood after learning how Japanese researchers had developed a see-through paper for use in flexible display screens for electronic devices.

The team began by pulling out the wood’s lignin (木质素). The lignin-free wood was then dipped into a polymer (聚合物) and baked at a temperature of 158F for four hours. The result was a hybrid product that was not only stronger and lighter than the original wood but also, almost transparent. The researchers were able to adjust the level of transparency by varying the amount of the polymer injected and also by changing the thickness of the wood.

While scientists have previously created a see-through wood for small-scale applications like computer chips, the transparent wood is the first one being considered for large scale applications. The researchers, who revealed their findings in Biomacromolecules on April 11, picture using the transparent wood in buildings to allow for more natural light, or to create windows that let in the desired amount of light without sacrificing privacy.

Wood that allows light to pass through could lead to a brighter future for homes and buildings. Berglund also thinks the wood could play a significant role in the design of solar panels. The semi-transparent material would be able to keep light longer and give it more time to interact with the conductor, thus resulting in better solar efficiency.

Additionally, substituting the currently used glass with this new product would help solar energy manufacturers improve their carbon footprint and lower the cost. They are now experimenting with ways to scale up the manufacturing process so that the transparent material is cost-effective to make and easy to use.

【推荐2】There’s a reason humans have been building homes from wood for 10,000 years. It’s an excellent building material. But since it’s not transparent (透明的), we’re still in the habit of cutting windows in our houses.

But what if wood could be made transparent?

Researchers in Sweden have been trying to do just that. They’ve created a clear wood material they hope could one day be used for more energy-saving building.

“We chemically made wood transparent”, says Celine Montanari, a researcher at the KTH Royal Institute of Technology in Stockholm.

Montanari and her team took wood and removed its lignin(木质素), and filled the resulting micro holes with a special chemical. Then the wood looked rather like the frosted glass of a shower door. They took the material one step further, mixing it with polyethylene glycol, a material that melts at 80 degrees Fahrenheit. When it melts, it absorbs energy and becomes transparent, then releases energy when cooled. In theory, this means the new wood material could be used to make windows that absorb energy during the hot part of the day and release it into the home when it gets cold at night. It makes the new wood an even more eco-friendly material by keeping indoor temperatures constant.

This is not a new technique, says Mark Swihart, a professor at University at Buffalo. Materials that store and release energy are not new either. “The thing that seems to be new is their way of the energy storage.” Swihart says.

Using wood as a base material is attractive because it has strength that’s hard to reproduce in other materials at the same cost, Swihart says. Whether or not the new transparent wood will be successful will depend in large part on how cheaply it can be made, he says. It’s also difficult to get new material widely used by the building industry, as there are existing supply chains for things like glass.

Montanari and her team are currently looking at increasing the heat storage capacity(储热性能) of the transparent wood, for greater energy savings. They’re also studying how to increase production to an industrial scale(规模). They hope to have a product ready for market within five years.

【推荐3】Electrical devices (电子仪器) could soon use power made by human energy. Scientists say they have developed an experimental device that produces electricity from the physical movement of a person walking, British scientist Max Donelan and other scientists in Canada and the United States developed the device.

The device connects to a person’s knee. As the person walks, the device captures energy each time the person slows down. To do this, the device helps with the slowing down movement of the leg, the movements of the walking person push parts of a small machine that produces electricity. Using the device, an adult walking quickly could produce thirteen watts of electricity in just a minute. Donelan says walking at that speed could produce enough power to operate a laptop computer for six minutes.

There are several possible uses for the device. Developers say it could help people who work in areas without electricity to operate small computers. The device could also be used in hospitals to operate heart pacemakers (起博器), and it could even be used to assist in the movement of robotic arms and legs.

The experimental version of the device weighs about one and a half kilograms, but it is too costly for most people to buy, but the researchers hope to make a lighter, less costly version. An improved version should be ready in one year.

The developers hope the device will one day help developing countries; nearly twenty five percent of people around the world live without electric power.

A similar product was invented in 2005 by Larry Rome of the University of Pennsylvania. He created a bag carried on a person’s back that also produces power from walking. The knee device does not produce as much electricity as the bag, but the bag requires the walker to carry a load of twenty to thirty kilograms.

【推荐1】You’re rushing to work and a man ahead of you collapses (跌倒) on the sidewalk. Do you stop to help? In a

study of by-standers, it was found that some people avert their gaze and keep on walking rather than stop and get involved. “There is a tendency to decide that no action is needed.” says a psychologist. “The first thoughts that pop into (进入) your mind often keep you from offering help. In order to take action, you have to work against them.” Here are some common thoughts that might prevent you from helping.

◆ Why should I be the one? I’m probably not the most competent (有能力的) person in this crowd. You might think someone older or with more medical knowledge should offer assistance (帮助).

◆ What if he doesn’t really need my help? The fear of embarrassment is powerful; no one wants to risk looking foolish in front of others.

◆ No one else looks concerned-this must not be a problem. We can follow the people around us, but most   people tend to hold back their emotions in public.

“If you spot (发现) trouble and find yourself explaining inaction, force yourself to stop and evaluate the situation instead of walking on,” says the psychologist. “Then retry to involve other people; you don’t have to take on the entire responsibility of being helpful. Sometimes it’s just a matter of turning to the person next to you and saying, “It looks like we should do something.” Or asking someone if an ambulance has been called and, if not, to call for one. Once you take action, most people will follow you.”

【推荐3】There are billions of people on this planet, and many of us love to eat meat. Can the demand be filled in a sustainable(可持续的) and affordable way? A bunch of businessmen are not only optimistic but are working to make this happen sooner than you may think.

The environmental effects caused by meat consumption (食用)—waste, animal treatment, health problems and even the greenhouse gas effects that are potentially caused by methane gas produced by cows—have given rise to a number of startups(新兴公司)looking to develop meats in different ways.

For example, San Francisco-based Memphis Meats is developing cell-based meats in its labs without requiring any animals. Israel’s Future Meat Technologies is doing the same by producing fat and muscle cells that are being tested by chefs in Jerusalem. All of these companies use special processes to harvest cells from animals and grow them in a lab.

But don’t worry if you’re not a meat lover. Startups such as Jet Eat, which is also based in Israel, are working on food products grown in labs that are plant-based and replicate (复制) meats using natural elements while still keeping flavor, consistency and the “overall sensory experience”, according to a report on NoCamels. Jet Eat, which was founded in early 2018, aims to 3D-print their lab-grown products by 2020.

As you can imagine, there are plenty of barriers facing the industry. Educating the public is a big one. Another controversial issue is the labeling of the products.   Recently both the USDA and the Food and Drug Administration(FDA) announced that they will begin jointly controlling the new “cell-based meat” category.

Many of us have concerns about the challenges facing future generations as our global population increases and the earth’s natural resources decreases. The good news is that there are plenty of businessmen around the world—like those producing lab-grown meats—who are working to solve some of these problems and make a little money in the process. Nothing wrong with that.