Bangladesh gets its first nuclear power plant

A new entrant to the nuclear club, heat-absorbing wonder material, the gravity of antimatter, and more in Science Notebook.

Workers at the Rooppur plant line the roads for the arrival of the nuclear fuel. | Photo Credit: Rosatom

WITH the delivery of the first batch of nuclear fuel to the upcoming Rooppur Nuclear Power Plant on October 5, Bangladesh became the 33rd nation to join the nuclear club.

The first unit of the plant, which is situated about 160 km from Dhaka, comprises two Russian VVER-1200 reactors. Construction began in November 2017, and the plant is scheduled to be commissioned in 2024. Construction of the second unit began in July 2018.

According to Rosatom, the Russian company that is building the plant and has delivered the fuel, the units have an initial life cycle of 60 years, with a further 20-year extension possible. The fuel was manufactured at Rosatom’s Novosibirsk Chemical Concentrates Plant and transported by air and road under the supervision of the Bangladesh Atomic Energy Regulatory Authority.

Speaking at the graduation ceremony via weblink, Russian President Vladimir Putin assured Bangladesh that Russia would provide assistance throughout the plant’s life cycle, including long-term supply of reactor fuel, maintenance of the nuclear plant, and management of spent nuclear material.

Carbon florets the new heat-absorbing wonder material

SOLAR energy is central to the most widely used renewable energy source in different forms such as photovoltaics and solar thermal conversion. However, these applications have been able to capture only a minuscule percentage of the total heat energy the sun radiates.

The marigold-like structured hard-carbon floret nanoparticles that have been found to be able to absorb more than 97 per cent of the UV, visible, and infrared components of sunlight. | Photo Credit: Prof. C. Subraminam, IITB

Now, a new material called nanostructured hard-carbon florets (NCF), designed by a team led by C. Subramaniam at IIT Bombay, has shown an unprecedented enhancement in the amount of heat that can be absorbed and stored. According to the IITB press release, this marigold-like structured material has been found to absorb more than 97 per cent of the UV, visible, and infrared components of sunlight, resulting in the very high solar-thermal conversion efficiency of over 87 per cent. The heat thus produced can be effectively transferred to either air or water for practical applications. “The study demonstrated that NCFs heat the air from room temperature to 60^oC and can thereby provide smoke-free space-heating solutions,” said the release. The work was published in a recent issue of Journal of the American Chemical Society.

Conventional solar-thermal converters, such as solar water heaters, use coatings and materials based on chromium (Cr) or nickel (Ni) films. Anodised chromium is a heavy metal and toxic to the environment. According to Ananya Sah, the lead author of the study that developed the NCFs, both Cr and Ni films exhibit efficiencies ranging between 60 and 70 per cent only. NCFs are made primarily of carbon and are environment-friendly, inexpensive to produce, and easy to use. Also, NCF coatings do not require vacuum jackets as other solar heat absorbers do, which are challenging to maintain, he said.

Antimatter falls the same way under gravity as matter

WATCHING a falling apple apparently inspired Isaac Newton to propound his historic theory of gravity. But would an “anti-apple” made of antimatter, if it were to exist, fall the same way? General relativity, which is Einstein’s modern theory of gravity, says that it should.

A descendant of the tree from which an apple reputedly fell and inspired Isaac Newton’s theory of gravitation, in the Botanic Garden in Cambridge, England.   | Photo Credit: Wikipedia Commons

One could not be sure of this before it was tested as there could be other long-range forces beyond gravity that affect antimatter’s free fall. And testing is not easy because one does not see antimatter in the universe. Now, the ALPHA collaboration at CERN’s Antimatter Factory has achieved that.

Within the precision of its experiment (20 per cent of gravitational acceleration, which is 9.81 m/s²), ALPHA has shown that atoms of antihydrogen—a positron orbiting an antiproton—fall to the earth the same way as hydrogen atoms, their matter equivalents, do. This was reported in a recent issue of Nature.

The ALPHA experiment facility at CERN, where antihydrogen atoms are made and trapped. | Photo Credit: Maximilien Brice/CERN

“In physics, you don’t really know something until you observe it,” ALPHA spokesperson Jeffrey Hangst said. “This is the first direct experiment to actually observe a gravitational effect on the motion of antimatter. It’s a milestone in the study of antimatter, which still mystifies us due to its apparent absence in the universe.” He added: “It has taken us 30 years to learn how to make this anti-atom, to hold on to it, and to control it well enough that we could actually drop it in a way that it would be sensitive to the force of gravity.”

New laser delivers a million pulses a second

THE newly upgraded next generation Linac Coherent Light Source (LCLS-II) at the SLAC National Accelerator Laboratory, California, which is an X-ray free electron laser (XFEL), produced its first light on September 18.

LCLS-II creates unprecedented capabilities and will usher in a new era of research with X-rays. | Photo Credit: Greg Stewart/SLAC National Accelerator Laboratory

LCLS-II can produce up to a million X-ray pulses/s, 8,000 times more than its earlier avatar, LCLS-I. It can produce an almost continuous X-ray beam that on average will be a world-record-setting 10,000 times brighter than its predecessor. LCLS-I, which was the world’s first “hard” X-ray (photons with energies of 5-10 kilo electronvolts or wavelengths of 0.2-0.1 nm) machine, had been in operation since April 2009. LCLS-I (like other existing XFELs) typically produced short and intense X-rays at about 100-120 pulses/s.

The LCLS-I accelerator was built out of copper and operating at room temperatures, while LCLS-II uses niobium, which is superconducting at the operating temperature of 2 K.

LCLS-II opens up unprecedented capabilities in X-ray research. “Scientists will be able to examine the details of quantum materials with unprecedented resolution…, reveal unpredictable and fleeting chemical events…, study how biological molecules carry out life’s functions… and study the world on the fastest timescales to open up entirely new fields of scientific investigation,” the SLAC news release said.