Lab Report

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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.

Dec. 14, 2018

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metamaterials
A new class of Lab-developed metamaterials employs a viscous, magnetically responsive fluid that is manually injected into the hollow struts and beams of 3D-printed lattices. The fluid’s ferromagnetic particles rapidly stiffen the fluid and the lattice structure. Photos by Julie Mancini/LLNL

New material stands firm

Magnetism transforms a weird new material from soft to rigid in a split second.

This metamaterial — a synthetic structure designed to behave in ways that natural materials don’t — comprises a gridlike network of plastic tubes filled with fluid that becomes more viscous in a magnetic field, causing the tubes to become firm. The material could help make more adaptable robots or body armor, Lawrence Livermore researchers report.

The team 3D printed lattices composed of plastic struts 5 millimeters long and injected them with a mixture of tiny iron particles and oil. In the absence of a magnetic field, the iron microparticles remain scattered randomly throughout the oil, so the liquid is runny. But close to a magnet, these iron microparticles align into chains along the magnetic field lines, making the fluid viscous and the lattices stiffer.

Material that becomes softer or stiffer on demand could be used to make next-generation sports pads or helmets with tunable impact absorption. Robots with changeable stiffness could squeeze into small spaces, but then be sturdy enough to carry or move other objects.

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montage
Lawrence Livermore National Laboratory has been honored with a Glassdoor Employees’ Choice Award, recognizing it as one of the Best Places to Work in 2019, as well as the top government contractor and top lab.

The best place to work

The workplace isn't what it used to be. There was a time when you could settle into a plum job and stay there until retirement, everything steady and secure.

That's not the case anymore. But Glassdoor reports there are still some great workplaces to land.

Lawrence Livermore comes up 24th on the list of 100, as well as the top government contractor and top lab. Glassdoor doesn't pick these companies subjectively but uses an algorithm that weighs reviews and ratings that both former and current employees have made during the past year.

Those reviews gauge feelings on everything from the CEO and senior management, to career opportunities, culture and values and work-life balance.

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climate
Arctic sea ice in September 2017, when the ice reached its annual minimum. In addition, a yellow line marks the 30-year average minimum sea ice extent from 1981 through 2010. Image courtesy of NASA.

Nature's fingerprints on Arctic sea ice loss

Arctic sea ice loss in the last 37 year is not due to humans alone.

New research by a Lawrence Livermore National Laboratory scientist and collaborators show that Arctic sea ice loss is enhanced by natural climate fluctuations such as El Niños and La Niñas. With manmade greenhouse gases on top of the natural climate variability, the decrease in sea ice is even more severe than climate models originally estimated.

Using a series of climate models, the team used a "fingerprint" method to estimate the impact of natural climate variability. Natural swings in the Earth's climate contribute to about 40 percent to 50 percent of the observed multi-decadal decline in Arctic sea ice.

"Internal variability can enhance or mute changes in climate due to greenhouse gas emissions. In this case, internal variability has tended to enhance Arctic sea ice loss," said Stephen Po-Chedley, an LLNL climate scientist

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home
Lawrence Livermore National Laboratory employees, along with Lawrence Livermore National Security, LLC, donated more than $3.7 million to charitable organizations via the annual employee giving program.

Giving campaign hits a HOME run

Lawrence Livermore National Laboratory employees, along with Lawrence Livermore National Security (LLNS), LLC, donated more than $3.7 million to charitable organizations via the annual employee giving program, the Helping Others More Effectively (HOME) Campaign.

Through the HOME Campaign, now in its 43rd year, Laboratory employees pledged $2,725,611 through payroll deduction. One-hundred percent of the funds donated go directly to agencies that are selected by employees.

LLNS, which manages the Laboratory for the Department of Energy's National Nuclear Security Administration, will add $1 million in prorated matching funds to augment employee donations, increasing the contribution value to more than $3.7 million.

Nearly 1,300 employees (18.5 percent) participated this year, benefiting more than 1,200 community/nonprofit agencies in the Tri-Valley, Greater Bay Area, San Joaquin County and beyond.

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sierra
Sierra is the second fastest supercomputer in the world and will serve the National Nuclear Security Administration’s three nuclear security laboratories. Photo by Randy Wong/LLNL

Reaching higher altitudes

Lawrence Livermore’s next generation of supercomputer — Sierra — is now the second fastest computer in the world, behind its partner, Summit, at Oak Ridge National Laboratory. Sierra will be used for stockpile stewardship.

China has been pushed into third place on a list of the world's most powerful supercomputers. The U.S. has five entries in the top 10, with other entries from Switzerland, Germany and Japan.

Supercomputers are typically large, expensive systems featuring tens of thousands of processors designed to carry out specialized calculation-intensive tasks, such as climate change studies, nuclear weapons simulations and weather forecasting.