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The crystalline solid BaTiS3 (barium titanium sulfide) is terrible at conducting heat, and it turns out that a wayward titanium atom that exists in two places at the same time is to blame.

The discovery, made by researchers from Caltech, USC, and the Department of Energy’s Oak Ridge National Laboratory (ORNL), was published on November 27 in the journal Nature Communications. It provides a fundamental atomic-level insight into an unusual thermal property that has been observed in several materials. The work is of particular interest to researchers who are exploring the potential use of crystalline solids with poor in thermoelectric applications, in which heat is directly converted into electric energy and vice versa.

“We have found that quantum mechanical effects can play a huge role in setting the thermal transport properties of materials even under familiar conditions like ,” says Austin Minnich, professor of mechanical engineering and applied physics at Caltech and co-corresponding author of the Nature Communications paper.

Hydropower has been around for more than a century, and is currently the nation’s largest source of clean, domestic, renewable electricity. What could its role look like in the year 2050?

Providing about 7 percent of the nation’s electricity, hydropower supports more than 143, 000 jobs in engineering, manufacturing, construction and utility operations and maintenance — all while improving the environment and strengthening our economy. Additionally, pumped-storage hydropower represents 97 percent of all energy storage in the United States, offering the flexibility and reliability the electricity grid needs to deliver affordable clean energy to American homes and businesses.

So what does the future of hydropower look like? To answer that question, over the past two years the Energy Department has collaborated with more than 300 experts from more than 150 hydropower industry companies, environmental organizations, state and federal governmental agencies, academic institutions, electric power system operators, research institutions and other stakeholders to explore how it could evolve in the coming decades.

Super-fast quantum computers and communication devices could revolutionize countless aspects of our lives—but first, researchers need a fast, efficient source of the entangled pairs of photons such systems use to transmit and manipulate information. Researchers at Stevens Institute of Technology have done just that, not only creating a chip-based photon source 100 times more efficient that previously possible, but bringing massive quantum device integration within reach.

“It’s long been suspected that this was possible in theory, but we’re the first to show it in practice,” said Yuping Huang, Gallagher associate professor of physics and director of the Center for Quantum Science and Engineering.

To create , researchers trap light in carefully sculpted nanoscale microcavities; as light circulates in the cavity, its photons resonate and split into entangled pairs. But there’s a catch: at present, such systems are extremely inefficient, requiring a torrent of incoming laser light comprising hundreds of millions of photons before a single entangled photon pair will grudgingly drip out at the other end.

Circa 2015


Conventional particle accelerators are typically big machines that occupy a lot of space. Even at more modest energies, such as that used for cancer therapy and medical imaging, accelerators need large rooms to accommodate the required hardware, power supplies and radiation shielding.

A new discovery by physicists at the University of Maryland could hold the key to the construction of inexpensive, broadly useful, and portable particle accelerators in the very near future. The team has accelerated electron beams to nearly the speed of light using record-low laser energies, thus relieving a major engineering bottleneck in the development of compact particle accelerators. The work appears in the November 6, 2015 issue of the journal Physical Review Letters.

“We have accelerated high-charge electron beams to more than 10 million electron volts using only millijoules of laser pulse energy. This is the energy consumed by a typical household lightbulb in one-thousandth of a second.” said Howard Milchberg, professor of Physics and Electrical and Computer Engineering at UMD and senior author of the study. “Because the laser energy requirement is so low, our result opens the way for laser-driven particle accelerators that can be moved around on a cart.”

Now more than ever both the importance and limitations of the global delivery infrastructure are on full display. But while Amazon and others try to speed up last mile delivery using drones, Dash Systems hopes to expedite the middle mile — with military-inspired airdrops putting pallets of parcels down at their penultimate destinations, even in the most inaccessible of locations.

Air-based delivery generally consists of four steps. First, an item is taken from the warehouse to the airport. Second, it goes by well-packed large cargo planes from there to another major hub, say from New York to Los Angeles. Third, a truck or smaller plane takes these to their regional destination, a sorting or distribution facility. Fourth, they go out on the familiar delivery trucks and end up on your doorstep.

It’s that third step that Joel Ifill, founder and CEO of Dash, felt could be improved. With an engineering background and experience building guided bombs for the military, he felt that there was an opportunity to apply some of the military’s point-to-point approach to the commercial sector. Why do you need to land at all?

A research group led by Prof. Chen Tao at the Ningbo Institute of Materials Technology and Engineering (NIMTE) of the Chinese Academy of Sciences (CAS), developed a novel soft self-healing and adhesive human-machine interactive touch pad based on transparent nanocomposite hydrogels, in cooperation with the researchers from the Beijing Institute of Nanoenergy and Nanosystems of CAS. The study was published in Advanced Materials.

With the rapid development of information technology and the Internet of things, flexible and wearable electronic devices have attracted increasing attention. A is a requisite input device for a mobile phone, smart appliance and point-of-information terminal. Indium tin oxide (ITO) has been used as the dominant transparent conductive film for manufacturing commercial touch pads, which inevitably have obvious shortcomings, like fragility.

To improve the stretchability and biocompatibility of touch pads to allow their interaction with humans, the researchers at NIMTE developed highly transparent and stretchable polyzwitterion-clay nanocomposite hydrogels with transmittance of 98.8% and fracture strain beyond 1500%.

More than two-thirds of the energy used worldwide is ultimately ejected as “waste heat.” Within that reservoir of discarded energy lies a great and largely untapped opportunity, claim scientists in MIT’s Department of Nuclear Science and Engineering (NSE). As reported in a recent issue of Nature Communications, the MIT team—led by Assistant Professor Mingda Li, who heads NSE’s Quantum Matter Group—has achieved a breakthrough in thermoelectric generation, which offers a direct means of converting thermal energy, including waste heat, into electricity.

A , or difference, within a material such as a metal or semiconductor can, through a phenomenon known as the Seebeck effect, give rise to an that drives a current. “For many materials, the is too low to be useful,” explains NSE Research Scientist Fei Han. “Our goal is to find materials with conversion efficiencies high enough to make thermoelectric generation more practical.”

The efficiency of thermoelectric energy conversion is proportional to a material’s , electrical , and something called the “” squared; it is inversely proportional to the . Because efficiency goes up with temperature, most thermoelectric materials used today operate in the range of hundreds of degrees centigrade. “But in our lives, most of the stuff around us is at room temperature,” Han says. “That’s why we’re trying to discover new materials that work effectively at or below room temperature.”

The United States generates seven million tons of sewage sludge annually, enough to fill 2, 500 Olympic-sized swimming pools. While a portion of this waste is repurposed for manure and other land applications, a substantial amount is still disposed of in landfills. In a new study, Texas A&M University researchers have uncovered an efficient way to use leftover sludge to make biodegradable plastics.

In the September issue of the journal American Chemical Society (ACS) Omega, the researchers report that the bacterium Zobellella denitrificans ZD1, found in mangroves, can consume sludge and wastewater to produce polyhydroxybutyrate, a type of biopolymer that can be used in lieu of petroleum-based plastics. In addition to reducing the burden on landfills and the environment, the researchers said Zobellella denitrificans ZD1 offers a way to cut down upstream costs for bioplastics manufacturing, a step toward making them more competitively priced against regular plastics.

“The price of raw materials to cultivate biopolymer-producing bacteria accounts for 25–45% of the total production cost of manufacturing bioplastics. Certainly, this cost can be greatly reduced if we can tap into an alternate resource that is cheaper and readily obtainable,” said Kung-Hui (Bella) Chu, professor in the Zachry Department of Civil and Environmental Engineering. “We have demonstrated a potential way to use municipal wastewater-activated sludge and agri-and aqua-culture industrial wastewater to make biodegradable plastics. Furthermore, the does not require elaborate sterilization processes to prevent contamination from other microbes, further cutting down operating and production costs of bioplastics.”

Am I reading this wrong? Sunelight is literally a cure / weapon against corona? Or am I missing something / making an incorrect logical link?


Researchers from Tel Aviv University (TAU) have proven that the coronavirus can be killed efficiently, quickly, and cheaply using ultraviolet (UV) light-emitting diodes (UV-LEDs). They believe that the UV-LED technology will soon be available for private and commercial use.

This is the first study conducted on the disinfection efficiency of UV-LED irradiation at different wavelengths or frequencies on a virus from the family of coronaviruses. The study was led by Professor Hadas Mamane, Head of the Environmental Engineering Program at TAU’s School of Mechnical Engineering, Iby and Aladar Fleischman Faculty of Engineering. The article was published in November 2020 issue of the Journal of Photochemistry and Photobiology B: Biology.

“The entire world is currently looking for effective solutions to disinfect the coronavirus,” said Professor Mamane. “The problem is that in order to disinfect a bus, train, sports hall, or plane by chemical spraying, you need physical manpower, and in order for the spraying to be effective, you have to give the chemical time to act on the surface. Disinfection systems based on LED bulbs, however, can be installed in the ventilation system and air conditioner, for example, and sterilize the air sucked in and then emitted into the room.

Andrew Glester reviews Not Necessarily Rocket Science: a Beginner’s Guide to Life in the Space Age by Kellie Gerardi

When the Apollo 11 astronauts landed on the Moon in 1969 the whole world stopped, just for a moment, and looked up. We stepped out into the universe and firmly entered the Space Age, which had begun with Sputnik just 12 years earlier. For many Physics World readers, the scientific and engineering exploits of those early achievements are a source of intrigue and no little excitement. From those crackled first words on the Moon, to images of the boot print in the lunar surface, or the new perspective of our world – the fragile blue marble suspended in darkness – humanity’s most impressive engineering effort has had a huge impact on our collective consciousness.

Commercial spaceflight industry professional and science communicator Kellie Gerardi was one of the many who wanted to be part of the nascent Space Age. But with a degree in film studies rather than aerospace engineering, her non-traditional path in the space industry is a key theme of her new book Not Necessarily Rocket Science: a Beginner’s Guide to Life in the Space Age. With more than 122, 000 followers on Instagram, Gerardi is something of a social-media star, and her book serves as part mission statement, part witness statement and part manifesto. They say that those converted to a cause are often the most evangelical and Not Necessarily Rocket Science brims with Gerardi’s passion – not just for the science and engineering of space exploration, but also for its democratization.