The International Union of Pure and Applied Chemistry (IUPAC) has confirmed that Lawrence Livermore National Laboratory scientists and international collaborators have officially discovered elements 115, 117 and 118. The announcement means those three elements are one step closer to being named. Lawrence Livermore teamed with the Joint Institute for Nuclear Research in Dubna, Russia (JINR) in 2004 to discover elements 113 and 115. LLNL worked again with JINR in 2006 to discover element 118. The LLNL/JINR team then jointly worked with researchers from the Research Institute for Advanced Reactors (Dimitrovgrad), Oak Ridge National Laboratory, Vanderbilt University and the University of Nevada, Las Vegas, to discover element 117 in 2010. This discovery brings the total to six new elements reported by the Dubna-Livermore team (113, 114, 115, 116, 117, and 118, the heaviest element to date). The IUPAC announced that a Japanese collaboration officially discovered element 113. The LLNL/JINR team had submitted a paper on the discovery of elements 113 and 115 about the same time as the Japanese group. In 2011, the IUPAC confirmed the name Livermorium for element 116. Livermorium (atomic symbol Lv) was chosen to honor Lawrence Livermore National Laboratory and the city of Livermore, Calif. A group of researchers from the Laboratory, along with scientists at the Flerov Laboratory of Nuclear Reactions at JINR, participated in the work carried out in Dubna on the synthesis of superheavy elements, including element 116. (Lawrencium -- Element 103 -- was already named for LLNL's founder E.O. Lawrence.)
One of the key research goals at Livermore’s National Ignition Facility (NIF) is demonstrating inertial confinement fusion ignition for both stockpile stewardship and as a potential source of clean energy. A paper published in the April 11, 2016, online issue of the journal Nature Physics reviews recent progress towards this goal. In the paper, Livermore scientists and colleagues analyze the series of National Ignition Facility “high-foot” inertial confinement fusion (ICF) experiments conducted in 2013 and 2014 that reached the highest levels of alpha heating ever achieved on any laser facility. Alpha heating, or self-heating, is a key step on the path to ignition in which the deuterium–tritium fusion reaction products deposit their kinetic energy locally within the fusion reaction region, thus increasing the temperature there and continually reinforcing the reaction rate.
Livermore material scientists have found that 3D-printed foams have higher durability and better long-term mechanical performance than standard cellular materials. The research appears in the April 27, 2016, edition of Scientific Reports. Foams, also known as cellular solids, are an important class of materials with applications ranging from thermal insulation and shock-absorbing support cushions to lightweight structural and flotation components. Foams are essential in the automotive, aerospace, electronics, marine, biomedical, packaging, and defense industries. At Livermore, better foam materials through advanced materials and manufacturing research have applications to national security missions in such areas as stockpile stewardship science, and energy. Traditionally, foams are created by processes that lead to a highly non-uniform structure with significant variety in size, shape, thickness, connectedness, and topology of constituent cells.
For more than two decades, LLNL researchers have worked to understand and mitigate climate change. Quantifying how much heat is accumulating in the ocean is critical to understanding climate change because the ocean absorbs more than 90 percent of Earth’s excess heat associated with global warming. Livermore scientists, together with colleagues from the National Oceanic and Atmospheric Administration, Princeton University, and Pennsylvania State University, have found that half of the global ocean heat content increase since 1865 has occurred during the past two decades and that the warming is reaching deeper into the ocean. Livermore researcher Peter Gleckler was lead author of a paper published in the January 18, 2016 online journal Nature Climate Change. The paper detailed a study that combined a diverse set of historical observations together with current climate models to identify changes in the ocean greater than 700 meters depth. The analysis suggests that nearly half of the industrial-era increases in global ocean heat content have occurred in recent decades, with over a third of the accumulated heat occurring below 700 meters. The estimates of ocean warming are consistent with results from the latest generation of climate models. Livermore’s contribution to the study was funded by the Department of Energy’s Office of Science.
Livermore scientists have been among the leaders in adopting, advancing, and demonstrating the capabilities of additive manufacturing, also called three-dimensional (3D) printing. In this revolutionary process, objects are built up one ultra-thin layer at a time. Researchers from LLNL and the University of California Santa Cruz achieved an important milestone when they used a 3D printer to manufacture grapheme aerogel supercapacitors that are extremely stable and capable of nearly fully retaining their energy capacity even after 10,000 consecutive charging and discharging cycles. The results were released online in the journal Nano Letters on January 28, 2016. The experimenters used a 3D-printing process called direct-ink writing and an extrudable graphene-oxide composite ink designed at LLNL. Graphene-based inks feature ultrahigh surface area, lightweight properties, elasticity, and superior electrical conductivity. The novel LLNL graphene composite ink has an engineered porous (aerogel) architecture. The researchers predict that future 3D-printed supercapacitors may make possible new products that are currently difficult or impossible to manufacture using other methods. Examples include efficient energy storage systems for smartphones, wearables, implantable devices, electric cars, and wireless sensors. Livermore’s Laboratory Directed Research and Development program funded this work.
Livermore researchers and partners have developed the first-ever biological identification method that exploits the information encoded in proteins of human hair. Scientists from Lawrence Livermore and a Utah startup company, Protein-Based Identification Technologies, LLC, have developed the groundbreaking technique. Their work, currently funded by the Department of Defense and the Laboratory Directed Research & Development program, is described in a paper in the online journal PLOS ONE. The method will offer another tool to law enforcement authorities for crime scene investigations as well as to archaeologists, since the technique can detect protein in human hair more than 250 years old. In their study, the researchers examined male and female hair samples of 66 European-Americans, 5 African Americans, 5 Kenyans, and 6 skeletal remains from the 1750s and 1850s, finding a total of 185 protein markers. The protein markers used by the scientists are variants resulting from amino acid substitutions that stem from DNA mutations, also known as single amino acid polymorphisms. Each person’s number of hair protein markers combined with their pattern of protein markers is unique, so researchers are able to provide a distinct pattern for an individual that would distinguish that person among a population of one million. The researchers’ ultimate goal is to establish a set of 90–100 protein markers that would identify an individual among the world’s population using a single hair—providing law enforcement with the capability of identifying remains that no current technique allows.
A team of Livermore researchers has developed protective yet breathable membrane materials featuring small-diameter (less than 5 nanometers) carbon nanotubes (CNT) as moisture-conductive pores. The membranes provide water vapor transport at a rate 20 times faster than those predicted by conventional gas diffusion theories, surpassing commercial breathable fabrics such as Gore-Tex. Their findings are described in a paper featured on the back cover of the July printed issue of the journal Advanced Materials. The team reported that these new CNT membranes can efficiently block biological threats such as Dengue virus because their size prevents them from passing through. Future work will aim to encode the membrane with a smart and dynamic response to chemical hazards, which could lead to a new paradigm of adaptive, breathable, and protective materials. The work was supported by the Defense Threat Reduction Agency’s “Dynamic Multifunctional Materials for a Second Skin” program and the Laboratory Directed Research and Development program.
Livermore engineers have achieved unprecedented scalability in 3D-printed architectures of arbitrary geometry, opening the door to super-strong, ultra-lightweight, and flexible metallic materials for aerospace, the military, and the automotive industry. In a study published online July 18 in Nature Materials, Laboratory engineers report building multiple layers of fractal-like lattices with features ranging from the nanometer to centimeter scale, resulting in a nickel-plated metamaterial with a high elasticity not found in any previously built metal foams or lattices. Metamaterials are synthetic composites with engineered properties that generally do not exist in natural materials. Prior to this achievement, no one had been able to scale up 3D features from the nanoscale to see how they behave. The lattices were initially printed out of polymers, using a one-of-a-kind Large Area Projection Micro-Stereolithography printer invented by Livermore engineer Bryan Moran, who won an R&D 100 award for the design. The lattice structure was then coated with a nickel-phosphorus alloy and then processed to remove the polymer core, leaving extremely lightweight, hollow tube structures of the alloy. 3D additively manufactured materials have direct application in the Laboratory’s stockpile stewardship mission, as well as in a broad array of applications requiring materials whose properties, such as compression, tension, and shear, can be tuned. The Laboratory Directed Research and Development program funded this research (15-LW-083), together with the Defense Advanced Research Projects Agency (DARPA) and a Virginia Tech startup.
A Lawrence Livermore team's dramatically improved first-principles molecular dynamics code that promises to enable new computer simulation applications was one of the finalists for the 2016 Gordon Bell Prize. The team presented its ground breaking project at the 2016 supercomputing conference (SC16) held in Salt Lake City, Utah Nov. 12-18. "Modeling Dilute Solutions using First-Principles Molecular Dynamics: Computing more than a Million Atoms with over a Million Cores," was the title of the Livermore team's submission for the competition. First-Principles Molecular Dynamics (FPMD) methods, although powerful, are notoriously expensive computationally because of the quantum modeling of electrons. Traditional FPMD approaches have typically limited simulations to a few thousand atoms at most. This is because of time and solver complexity and the large amount of communication required for highly parallel implementation. Previous attempts to lower the complexity have tended to introduce uncontrolled approximations or systematic errors that compromise accuracy. Using a robust new algorithm, the Livermore team has developed an O(N)complexity solver for electronic structure problems with fully controllable numerical error. The team demonstrated on Lawrence Livermore's Sequoia supercomputer that the code's minimal use of global communications provides excellent scalability, allowing very accurate FPMD simulations of more than a million atoms on more than a million (computer) cores. At these scales, this approach provides multiple orders of magnitude speedup compared to the standard 'plane-waves' approach typically used in condensed matter applications, without sacrificing accuracy. This will open up new classes of FPMD simulations, such as dilute aqueous solutions.
Material scientists at Lawrence Livermore National Laboratory have found certain metal oxides increase capacity and improve cycling performance in lithium-ion batteries. The team synthesized and compared the electrochemical performance of three graphene metal oxide nanocomposites and found that two of them greatly improved reversible lithium storage capacity. The research appears on the cover of the March 21 edition of the Journal of Materials Chemistry A. Graphene-metal oxide (GMO) nanocomposites have become renowned for their potential in energy storage and conversion, including capacitors, lithium-ion batteries, sensors and catalysis (for fuel cells, water splitting and air cleaning). For applications in lithium-ion batteries, nanosized metal oxide (MO) particles and highly conductive graphene are considered beneficial for shortening lithium diffusion pathways and reducing polarization in the electrode, leading to enhanced performance. In the experiments, the team dipped prefabricated graphene aerogel electrodes in metal ion solutions where all metal oxide nanoparticles appear to be anchored on the surface of graphene and are fully accessible to the electrolyte (i.e., open pore space).