838,649 articles

Using green tea as reducing reagent for the preparation of nanomaterials to synthesize ammonia

Researchers have shown that green tea can be used as a reducing reagent for the preparation of nanomaterials to synthesize ammonia. Compared with bulk graphitic carbon nitride, the optimal sample had 2.93-fold photocatalytic nitrate reduction to ammonia activity (2.627 mg/h/gcat), and the NH3 selectivity increased from 50.77% to 77.9%. The team published their approach on September 06 in Energy...

Lightweight space robot with precise control developed

Robots are already in space. From landers on the moon to rovers on Mars and more, robots are the perfect candidates for space exploration: they can bear extreme environments while consistently repeating the same tasks in exactly the same way without tiring. Like robots on Earth, they can accomplish both dangerous and mundane jobs, from space walks to polishing a spacecraft's surface. With space...

Air bubbles sound climate change's impact on glaciers

As the world's temperatures rise, tidewater glaciers are receding and melting, releasing air trapped in the ice. Scientists can listen to the release of the air and potentially use the sounds to help them gauge the impact of climate change on the ice floes.

What's Up: December 2021

What's Up for December? Your early evening highlights, a chance to catch a comet, and the annual Geminid meteors. See three planets after sunset, but say goodbye to Venus as the "Evening Star" at the end of the month. Then have a hunt for newly discovered Comet Leonard in the early morning through mid-month. Finally, get up early on Dec. 14 to watch for Geminid meteors after local moonset,...

Does the Omicron variant mean Covid is going to become more transmissible?

As new strain dampens idea pandemic might be diminishing, what does the future hold for coronavirus?Coronavirus – latest updatesSee all our coronavirus coverageWhen scientists predicted, months ago, that Covid-19 could be entering an endemic phase, many felt ready for the crisis period of the pandemic to be over. The tantalising suggestion that coronavirus might, at some foreseeable point, be...

Two-dimensional bipolar magnetic semiconductors with electrically controllable spin polarization realized

Two dimensional (2D) magnetic semiconductors, integrating semiconductivity, ferromagnetism and low dimensionality, serve as the cornerstone for high-speed nanospintronic devices. However, the practical applications of nowadays 2D magnetic semiconductors face two key problems: the rather low magnetic Curie temperature compared to room temperature, and the lack of a simple and efficient method to...

Antarctica experiences rare total solar eclipse

A rare total solar eclipse in Antarctica this weekend (Saturday 4 December) is giving researchers a unique opportunity to learn more about how solar eclipses affect space weather. The next total eclipse in Antarctica will not be until 2039.

The role of messenger RNA in DNA repair

An organism's genome could be compared to a complex system of instructions that allows it not only to develop, but also to carry out all the activities essential to its survival. To do this, this genome needs to be expressed correctly, i.e. these instructions need to be "read" properly, and the information it contains must not be altered or degraded over time.

Tropical forests recover after deforestation

Tropical forests are disappearing at an alarming rate through deforestation, but they also have the potential to regrow naturally on abandoned lands. This has been shown by an international study led by scientists from Wageningen University. How a forest recovers, depends on the amount of rainfall, the age of the forest, and the functional characteristics of the tree species.

Astronomers discover hot, dense planet with eight-hour year

In a new study, published in the journal Nature, the researchers show that the planet, which is 31 light years from Earth, is one of the lightest among the nearly 5,000 exoplanets (planets outside our own solar system) that are known today, with half the mass of Earth. It has a diameter of just over 9,000 kilometers—slightly larger than Mars.

Invasive ants can threaten ecosystems by damaging plants at the roots

Invasive ant species can be found in almost every ecosystem on earth, but the impact these invaders may have on plant health has only recently been investigated by scientists. A new study published in Journal of Ecology is the first of its kind to find that invasive ants can disrupt plants' growth and photosynthesis by nesting at their roots—potentially threatening plants in tropical and...

Exoplanets in debris disks

Debris disks around main-sequence stars are tenuous belts of dust thought to be produced when asteroids or other planetesimals collide and fragment. They are common: more than about a quarter of all main-sequence stars have debris disks and, since these disks can be hard to detect, it is likely that the fraction is even higher. Current instruments are only able to detect debris disks in systems...

Development of a single-process platform for the manufacture of graphene quantum dots

Graphene consists of a planar structure, with carbon atoms connected in a hexagonal shape that resembles a beehive. When graphene is reduced to several nanometers (nm) in size, it becomes a graphene quantum dot that exhibits fluorescent and semiconductor properties. Graphene quantum dots can be used in various applications as a novel material, including display screens, solar cells, secondary...

Inside the tectonic wake of a migrating restraining bend: Mount Denali—the highest mountain peak in North America

In their recent publication, "Why is Denali (6,190 m) so big? Caught inside the tectonic wake of a migrating restraining bend," Jeff A. Benowitz and a research team from the University of Massachusetts Amherst, Virginia Tech, and the South Dakota School of Mines and Technology in the U.S., documented the evolution of the Mount McKinley bend of the Denali Fault.