LAB REPORT
Science and Technology Making Headlines
Feb. 23, 2018
Big things come in small packages
Lawrence Livermore researchers have developed techniques that promise to redefine the limits of nanoscale 3D printing.
These advances extend the capabilities of two-photon lithography (TPL), a high-resolution additive manufacturing technique capable of producing complex, 3D microstructures, with features two to three orders of magnitude finer than human hair.
The techniques also overcome barriers that have limited the functionality of conventional single-photon lithography systems. Lawrence Livermore’s research aims to uncover design rules for synthesizing photopolymers, with an eye on optimizing TPL for X-ray absorption, which will allow engineers to noninvasively evaluate the physical integrity of 3D-printed devices.
California could come up dry
The blocking high-pressure zone that has moved most California storms north strongly correlates with the loss of Arctic sea ice. It could be mean more droughts like those experienced during the past decade.
A recent study by scientists at Lawrence Livermore National Laboratory and UC Berkeley found that more heat being stored in the Arctic Ocean is leading to changes in atmospheric circulation and the buildup of a high-pressure system in the eastern Pacific. It is what one meteorologist is calling California’s “ridiculously resilient ridge.”
Modeling suggests that loss of Arctic ice could result in a 10 to 15 percent reduction in California rainfall over time.
Ice, ice baby
Lawrence Livermore scientists have discovered an incredible new form of water ice that is both a solid and a liquid at the same time.
First theorized almost 30 years ago, this is the only time that direct evidence for superionic ice has been found. The team used powerful lasers to heat pressurized ice in the lab, recreating the conditions needed to form the strange substance here on Earth.
Studying it could lead to the development of new materials in the future with unique and unforeseen properties, as well as furthering understanding of the cosmos.
Droning about delivery options
A new Lawrence Livermore study concludes that using battery-powered drones for consumer package deliveries can be more climate-friendly than diesel trucks under certain circumstances.
The analysis of greenhouse gas emissions from competing delivery methods comes as corporate giants like Amazon, Google and UPS are exploring use of drones.
The team modeled total emissions under different drone sizes, package weights, transportation fuels for ground-based deliveries, energy needs for additional warehousing to support increased drone use, and -- crucially -- the electricity source in the regions modeled.
They compared estimated emissions from trips in California -- where natural gas, renewables and nuclear energy provide the electricity mix -- to deliveries in Missouri, where coal is the dominant power source.
Next big one could hit the East Bay
In the next 30 years, there is a one-in-three chance that the Hayward fault will rupture with a 6.7 magnitude or higher earthquake. Such an earthquake will cause widespread damage to structures, transportation and utilities, as well as economic and social disruption in the East Bay.
Scientists from Lawrence Livermore and Lawrence Berkeley laboratories recently modeled ground shaking from a magnitude 7.0 Hayward Fault earthquake in greater detail than ever before. This is the highest resolution earthquake simulation ever done for Northern California.
Principal investigator Artie Rodgers, a seismologist at Lawrence Livermore, said the team is working to “compute the most realistic, fully deterministic 3D ground motions for use in hazard, risk and building/structural response analysis.”
For residents of the San Francisco East Bay, the greatest seismic hazard is the Hayward Fault. As this nearly 80-mile-long fault snakes its way from just east of San Jose to San Pablo Bay, where it transitions to the Rodgers Creek Fault, it cuts through the cities of Hayward, Fremont, Oakland and Berkeley. While the Hayward Fault may not have the notoriety of the San Andreas, it is part of the same larger fault system, and according to the USGS, has a greater chance of rupturing in a large earthquake by 2043.