Researchers Create World’s First Reactor-Scale Fusion Machine
ITER, the world’s first reactor-scale fusion machine, will have a plasma volume more than 10 times that of the next largest tokamak, JET. Plasma disruptions that can occur in a tokamak when the plasma becomes unstable can potentially damage plasma-facing surfaces of the machine. To lessen the impact of high energy plasma disruptions, US ITER is engaged in a global research effort to develop disruption mitigation strategies.
US ITER, managed by DOE’s Oak Ridge National Laboratory, will continue working closely with global partners on the ITER disruption mitigation system, as the 2016 deadline for design of the system rapidly approaches. To continue moving R&D forward, an early conceptual design review was supported by US ITER in November.
Read more: http://www.laboratoryequipment.com/news/2013/01/researchers-create-world%E2%80%99s-first-reactor-scale-fusion-machine
Researchers Bring ‘Quantum Singularity’ Closer
In early 2011, a pair of theoretical computer scientists at MIT proposed an optical experiment that would harness the weird laws of quantum mechanics to perform a computation impossible on conventional computers. Commenting at the time, a quantum-computing researcher at Imperial College London said that the experiment “has the potential to take us past what I would like to call the ‘quantum singularity,’ where we do the first thing quantumly that we can’t do on a classical computer.”
The experiment involves generating individual photons — particles of light — and synchronizing their passage through a maze of optical components so that they reach a battery of photon detectors at the same time. The MIT researchers — Scott Aaronson, an associate professor of electrical engineering and computer science, and his student, Alex Arkhipov — believed that, difficult as their experiment may be to perform, it could prove easier than building a fully functional quantum computer.
In December, four different groups of experimental physicists, centered at the Univ. of Queensland, the Univ. of Vienna, the Univ. of Oxford and Polytechnic Univ. of Milan, reported the completion of rudimentary versions of Aaronson and Arkhipov’s experiment. Papers by two of the groups appeared back to back in the journal Science; the other two papers are as-yet unpublished.
Read more: http://www.laboratoryequipment.com/news/2013/01/researchers-bring-%E2%80%98quantum-singularity%E2%80%99-closer
Why is the Universe Dominated by Matter, Not Anti-Matter? |
A collaboration with major participation by physicists at the University of Wisconsin-Madison has made a precise measurement of elusive, nearly massless particles, and obtained a crucial hint as to why the universe is dominated by matter, not by its close relative, anti-matter.
The particles, called anti-neutrinos, were detected at the underground Daya Bay experiment, located near a nuclear reactor in China, 55 kilometers north of Hong Kong. For the measurement of anti-neutrinos it made in 2012, the Daya Bay collaboration has been named runner-up for breakthrough of the year from Science magazine.
Anti-particles are almost identical twins of sub-atomic particles (electrons, protons and neutrons) that make up our world. When an electron encounters an anti-electron, for example, both are annihilated in a burst of energy. Failure to see these bursts in the universe tells physicists that anti-matter is vanishingly rare, and that matter rules the roost in today’s universe.
“At the beginning of time, in the Big Bang, a soup of particles and anti-particles was created, but somehow an imbalance came about,” says Karsten Heeger, a professor of physics at UW-Madison. “All the studies that have been done have not found enough difference between particles and anti-particles to explain the dominance of matter over anti-matter.”
But the neutrino, an extremely abundant but almost massless particle, may have the right properties, and may even be its own anti-particle, Heeger says. “And that’s why physicists have put their last hope on the neutrino to explain the absence of anti-matter in the universe.”
Heeger and his group at UW-Madison have been responsible for much of the design and development of the anti-neutrino detectors at Daya Bay. Jeff Cherwinka, from the university’s Physical Sciences Laboratory in Stoughton, Wis. is chief engineer of the experiment and has overseen much of the detector assembly and installation. The construction of the experiment was completed this fall and data-taking started in October using the full set of anti-neutrino detectors. continue reading
This video features simulation of the laminar flow around a plate plunging sinusoidally in a quiescent flow. As the plate moves up and down, it mixes the fluid around it. This is visualized in several ways, beginning with the vorticity. Clockwise and anti-clockwise vortices are shed by the edges of the plate as it moves. The flow is also visualized using particle trajectories, which are classified by their tendency to accumulate (attract) or lose (repel) particles. These trajectories are particularly intriguing to watch develop as they appear to show ornate faces and designs. (Video credit: S. L. Brunton and C. W. Rowley)
Bacteria do math. The KPZ equation (), which describes the growth of the stain left by a drying liquid drop containing ellipsoidal particles, may also describe the growth pattern at the edges of bacterial colonies.
In the collage above, successive frames showing the bouncing and break-up of liquid droplets impacting a solid inclined surface coated with a thin layer of high-viscosity fluid have been superposed. This allows one to see the trajectory and deformation of the original droplet as well as its daughter droplets. The impacts vary by Weber number, a dimensionless parameter used to compare the effects of a droplet’s inertia to its surface tension. A larger Weber number indicates inertial dominance, and the Weber number increases from 1.7 in (a) to 15.3 in (d). In the case of (a), the impact of the droplet is such that the droplet does not merge with the layer of fluid on the surface, so the complete droplet rebounds. In cases (b)-(d), there is partial merger between the initial droplet and the fluid layer. The impact flattens the original droplet into a pancake-like layer, which rebounds in a Worthington jet before ejecting several smaller droplets. For more, see Gilet and Bush 2012. (Photo credit: T. Gilet and J. W. M. Bush)
Graphene: The Miracle Material
Graphene is 200 time stronger than steel, harder than diamond, super flexible, and an excellent conductor of heat and electricity—and yet is only one atom thick. It’s a material made out of a single layer of pure carbon atoms, arranged in a honeycomb lattice connected by the strongest bonds known to science. Basically, graphene is just a super-thin sheet of graphite, the material found in pencils—so thin that a stack of three million sheets would be just 1 mm thick. Physicists Andre Geim and Konstantin Novoselov discovered it in 2004, and later received a Nobel Prize for their work because graphene is an incredibly versatile material—comparable to the vast range of uses that plastic has—and can even be modified to take on different properties: researchers have successfully made it magnetic. Graphene’s amazing mechanical, electrical and optical properties mean that it could be used for vast range of applications, from stronger and lighter car and airplane parts, to super-tough textiles, to healthcare, to a replacement for silicon in nano-electronics—which could lead to faster, thinner and more flexible electronic devices. It may be some years before we see these applications fully realised because there are still obstacles to overcome, but there’s no doubt that graphene has incredible and unparalleled potential.
Badass Scientist of the Week: Dr. John Paul Stapp
John Paul Stapp (1910–1999) was a flight surgeon, a US Air Force Officer, and a pioneer of aviation safety—specifically of the human body’s ability to withstand G forces during deceleration. Stapp initially wanted to become a writer and received a BA in English, but changed direction to achieve an MA in Zoology and a PhD in Biophysics. He spent two years teaching to be able to afford medical school, and then after completing his medical internship in 1944, he entered military service. Around that time, an experimental deceleration project had begun that conducted crash tolerance tests with the hopes of improving safety measures in military aircraft. Stapp volunteered to be a test subject in the project’s rocket sled, “Sonic Wind I”, which was built for fast speeds and short braking distances. By 1954, he had conducted 29 crash tests, travelling up to a then-world record breaking 1017 km per hour and braking as quickly as 1.4 seconds, sustaining up to 46.2 Gs of force in the process. He suffered countless injuries from these tests, including rib fractures, retinal haemorrhages, and two wrist fractures (one of which he reset himself while strolling back to base). But his painful sacrifices were invaluable—they paved the way for improved helmets, seats, arm and leg restraints, and safety harnesses. Stapp was proclaimed the “Fastest Man Alive” and shot to international fame, and he used this fame to promote automobile safety—he believed that safety measures in military aircraft should be used in civilian motor vehicles too, and his efforts resulted in a bill requiring seatbelts in all new cars. Later, Stapp directed the Manhigh Project to study human endurance at the edge of space, and was elected to the Space Hall of Fame and the National Aviation Hall of Fame. He died in 1999, but his work undoubtedly still saves thousands of lives a year.
Researchers Create World’s Smallest Reaction Chamber
Scientists from New Zealand, Austria and the UK have created the world’s smallest reaction chamber, with a mixing volume that can be measured in femtoliters (million billionths of a liter).
Using this minuscule reaction chamber, lead researcher Peter Derrick, professor of chemical physics and physical chemistry and head of the Institute of Fundamental Sciences at Massey Univ. in New Zealand, plans to study the kind of speedy, nanoscale biochemical reactions that take place inside individual cells. This work appears in the latest issue of the European Journal of Mass Spectrometry.
Read more: http://www.laboratoryequipment.com/news/2012/12/researchers-create-world%E2%80%99s-smallest-reaction-chamber