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.

Feb. 17, 2023

target chamber

NIF beamlines entering the lower hemisphere of the NIF target chamber. LLNL researchers achieved ignition late last year using NIF and entered a new path toward a fusion economy.

U.S. is the top dog in fusion

The United States is the most advanced nation when it comes to fusion energy. It is home to 21 fusion energy startups, and has 83 publicly funded fusion research projects. The most prominent of these startups include TAE Technologies and Helion Energy.

Helion has raised $500 million in Series E funding and plans to demonstrate the generation of net electricity from fusion in 2024.

When it comes to research projects, Lawrence Livermore National Laboratory has recently made headlines for its National Ignition Facility, which demonstrated proof of concept of the engineering viability of fusion, with a net gain in energy.  

crops

The Growing Climate Solutions Act was devised to get the nation’s growers to adopt climate-friendly practices by encouraging their participation in the carbon market. Image by Adobe Stock.

grist

Soil alone can’t get rid of the carbon footprint

When Congress passed an omnibus spending bill in December, it included a bit of bipartisan climate legislation that had been languishing on the Hill since its introduction in 2020. The Growing Climate Solutions Act, supported by climate advocates and farmers alike, was devised to get the nation’s growers to adopt climate-friendly practices by encouraging their participation in the carbon market. 

The Biden administration’s climate strategy includes investing in so-called nature-based solutions like storing carbon in soil. Some of the methods analyzed included planting crops in the off season to pull more carbon into the soil, a practice called cover copping; reducing tillage, which can limit the carbon-releasing decay of organic matter in the soil; and converting cropland to grasses or other perennials.

However the bill does nothing to address key questions about the underlying science of soil carbon sequestration, and whether carbon offsets are even an effective way to incentivize it.

There’s a risk that a federal directory of carbon credit companies “could give a veneer that the carbon markets are more mature than they really are,” said Eric Slessarev, a soil ecologist at Lawrence Livermore National Laboratory.

Part of the challenge is that scientists are still untangling a central mystery around soil carbon. “Why does some soil carbon persist? And why does the remainder not? And how does that play out differently in different places?” Slessarev said. “We know that these things are place-dependent, but we don’t quite understand how or why.”

But carbon sequestrations has to be done for the long haul. A decade or even two of carbon sequestration is inadequate because the carbon dioxide spewed into the atmosphere by those buying offsets will remain there for millennia.

“​​I don’t think we’re ever going to get to a point where soil organic carbon is going to be exchangeable with fossil fuel emission, even if we were to get really, really good at measurements,” Slessarev said. “There’s just no way to know how persistent the carbon will be. It depends on not just biophysical factors that people like me can evaluate, but socio-economic ones.”

ice

The researchers’ setup for creating medium-density amorphous ice involved placing ordinary ice and steel balls in a jar. Image courtesy of Christoph Salzmann/ University College London.

It’s really cool

Scientists have created a new type of ice that matches the density and structure of water, perhaps opening a door to studying water’s mysterious properties.

The ice is called medium-density amorphous ice. The team shook regular ice in a small container with centimeter-wide stainless-steel balls at temperatures of –200 ˚C to produce the variant, which has never been seen before. The ice appeared as a white granular powder that stuck to the metal balls.

The results are “pretty convincing,” said Marius Millot, a physicist at the Lawrence Livermore National Laboratory, who was not involved in the research but has created and ice called "superionic ice." “This is a great example of how we still have things to understand with water.”

The results matched models produced by scientists on the team at the University of Cambridge, predicting what would happen if regular ice was broken down in this manner. It’s unclear, however, whether the resultant powder truly matches the properties of liquid water, given that it was previously frozen as crystallized ice.

microprisms

Hydrogen absorption at the surface of magnesium diboride (MgB2) studied with first principles simulations. The background depicts MgB2 crystallites. Image by Liam Krauss/LLNL.

It is but wafer thin

A collaboration including scientists from Lawrence Livermore, Sandia National Laboratories, the Indian Institute of Technology Gandhinagar and Lawrence Berkeley National Laboratory has created 3-4 nanometer ultrathin nanosheets of a metal hydride that increase hydrogen storage capacity significantly.

Hydrogen has the highest energy density of any fuel and is considered a viable solution for ground transportation, aircraft and marine vessels. However, hydrocarbon fuel sources outperform compressed hydrogen gas in terms of volumetric energy density, motivating the development of alternative, higher-density materials-based storage methods.

Complex metal hydrides are a class of hydrogen storage materials that, while having high absolute storage capacity, can require extreme pressures and temperatures to achieve that capacity. The team tackled this challenge by nano-sizing, which increases the surface area to react with hydrogen and decreases the required depth of hydrogenation.

The material created in this most recent collaboration came from solvent-free mechanical exfoliation in zirconia, yielding material that is only 11-12 atomic layers thick and can hydrogenate to about 50 times the capacity of the bulk material.

explosives

For the anisotropy research team tests, high explosives handlers packed different designs, assembled and detonated more than 50 rounds over the course of four days. Shown are different unlined C-4 shaped charges and a clamped PETN booster, staged for range detonation testing. Photo by Lawrence Livermore National Laboratory

news7f

Making safer explosives

Lawrence Livermore scientists and engineers led a multi-institutional team that carried out a series of high explosives tests that successfully demonstrated the fundamentals of anisotropy, an element that can help improve the safety of weapons and ammunition.

Working in snow and cold conditions in Idaho’s Snake River Delta, a 13-member team from the LLNL conducted 52 explosive launches over four days at the National Security Test Site (NSTR) of the Idaho National Laboratory (INL) to complete the study. The broader anisotropy research team (ANISO) includes high explosives handlers and volunteers from INL, Los Alamos National Laboratory, Marine Raiders from Sea Special Operations Command and members of the United States Special Operations Command.

The aim of the study was to explore theoretical methods for generating anisotropic explosives – explosives that behave differently depending on the direction of the detonated waves moving through explosives — by certain technique physical features in the costs and get basic data from the test.

This work is part of a joint effort by the Laboratory to develop anisotropic explosives that can be used in ammunition to reduce the severity and lethality of an unintended explosion without compromising to performance. The data collected from the study will be used to design and build follow-up experiments at LLNL’s High Explosives Application Facility (HEAF) and validate computer models for future anisotropic assemblies.