LAB REPORT

Science and Technology Making Headlines

Oct. 26, 2018


Sierra, one of the fastest supercomputers in the world, will serve the National Nuclear Security Administration’s three nuclear security laboratories, providing high-fidelity simulations in support of NNSA’s core mission of ensuring the safety, security and effectiveness of the nation’s nuclear stockpile. Photo by Randy Wong/LLNL

Faster than a speeding bullet

The Department of Energy’s National Nuclear Security Administration (NNSA), Lawrence Livermore National Laboratory (LLNL) and its industry partners officially unveiled Sierra, one of the world’s fastest supercomputers, at a dedication ceremony Friday (Oct. 26) to celebrate the system’s completion.

Sierra boasts a peak performance of 125 petaFLOPS — 125 quadrillion floating-point operations per second.

Sierra will serve the NNSA’s three nuclear security laboratories, LLNL, Sandia National Laboratories and Los Alamos National Laboratory, providing high-fidelity simulations in support of NNSA’s core mission of ensuring the safety, security and effectiveness of the nation’s nuclear stockpile. Its arrival represents years of procurement, design, code development and installation, requiring the efforts of hundreds of computer scientists, developers and operations personnel working in close partnership with IBM, NVIDIA and Mellanox.

“Today we mark our latest milestone toward computing on a truly exascale level,” Department of Energy Secretary Rick Perry said in a video message prepared for the dedication. “With its dramatic unveiling of Sierra, Lawrence Livermore National Laboratory has taken a pivotal step forward on behalf of America’s national security.”


A scanning electron microscope image of the 3D-printed graphene aerogel lattice. Credit:Bin Yao/University of California, Santa Cruz

Supercharged

Lawrence Livermore and UC Santa Cruz scientists have created a new supercapacitor that could one day store as much if not more energy than batteries.

They invented a new 3D printed capacitor that stores a record-breaking amount of charge over a given surface area.

The new technique uses a 3D printer to construct a microscopic scaffold with porous graphene and then fills the structure with a kind of material called a pseudocapacitive gel, which is a kind of capacitor material that also behaves like a battery in some ways.

Capacitors are a basic component in almost all electronic devices. Like batteries, capacitors can be charged and discharged for storing and releasing electricity. Capacitors can charge and discharge much faster than batteries but cannot hold as much energy if the two are the same size.

Using the new 3D-printed scaffold with porous graphene, the researchers were able to increase the mass-loading in their device more than 10 times compared to the typical stacking technique, resulting in a much higher areal capacitance.


Supercomputer simulations of shock-induced explosive reactions suggest that the microstructure of heterogeneous solid explosive materials impact performance and safety.

Explosive discovery

In a move that could make demolition teams breathe a bit easier, scientists at Lawrence Livermore National Laboratory are studying the structure of high explosives to find out how to make them safer. Based on microscopic examination and computer modeling, they have found that by engineering the porous microstructure of explosives, their sensitivity to detonation can be controlled.

Ever since explosives were invented, chemists and others have been working on ways to make them less likely to explode when they shouldn't. But even the best explosives have to be handled with respect because the factors involved in making them detonate aren't completely understood.

A team led by research scientist Keo Springer of LLNL's High Explosives Applications Facility found was that it wasn't just the chemistry that plays a part, but the tiny holes, pores and defects in the explosive itself.

"We found out that when pores are at the surface, they speed up the reaction," Springer said. "We also discovered that if a shockwave hits a number of surface pores at once, they bootstrap each other. It's an explosive party, and they party well together."


Better farming practices could return CO2 in the atmosphere back to the soil to help tackle climate change, according to an LLNL scientist.

Zeroing out carbon emissions

The latest Intergovernmental Panel on Climate Change report lays out a grim set of observations, predictions and warnings. The biggest takeaway: The world cannot warm more than 1.5 degrees Celsius over pre-industrial levels without significant impacts.

If the world warms a mere half degree more than that, hundreds of millions of people could face dire consequences — famine, disease and displacement — from things like rising sea levels and increased droughts and flooding.

Limiting our carbon footprint is more than just turning down the thermostat and driving less. It comes down to reaching negative emissions -- removing much of the CO2 that has already been released. Roger Aines, chief scientist of the energy program at Lawrence Livermore National Laboratory, said we need to get started with widely employing technologies capable of removing CO2 from the air.

“The last 200 years or so, we have lost the equivalent of 500 gigatons of carbon dioxide from the carbon content of our agricultural soil. So, it’s reasonable to say, if we use good agricultural practices, that we can return that carbon from the air to the soil,” he said. While a variety of negative emissions technologies must be employed together to tackle climate change, better land use practices are the ones most likely to have the “biggest impact,” he added.


The Martian meteorite known as "Black Beauty." Credit: NASA

A little piece of Mars

Thanks to a meteorite, NWA 7034 (named “Black Beauty”), that crashed down in Africa in 2011, scientists have been able to analyze the rock and determine that it came from Mars.

The analysis by Lawrence Livermore scientists and colleagues determined that Mars formed much earlier than originally predicted.

By the time the solar system was 20 million years old, the formation of Mars had already proceeded far enough to form a solid rocky crust — a necessary precondition for water vapor in the atmosphere to condense into oceans as the planet gradually cooled.

LLNL researchers noted that between 1.3 and 1.7 billion years ago, volcanic eruptions reshaped the surface from which NWA 7034 later came. Later still, came another massive impact on Mars that knocked “Black Beauty” into space, where it finally collided with Earth and ended up in the Sahara Desert a few thousand years ago.

Things changed greatly when Mars lost its global magnetic field around 4 billion years ago. The solar wind began stripping the planet's once-thick atmosphere, and the world transitioned to the cold, dry desert it is today. 

Computer with email graphic

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The Lab Report is a weekly compendium of media reports on science and technology achievements at Lawrence Livermore National Laboratory. Though the Laboratory reviews items for overall accuracy, the reporting organizations are responsible for the content in the links below.