A new technique from the Lawrence Livermore National Laboratory (LLNL) for increasing production of organized single-walled carbon nanotubes (SWCNTs) was announced in an October 25, 2022 news item on Nanowerk, Note: A link has been removed,
Lawrence Livermore National Laboratory (LLNL) scientists are scaling up the production of vertically aligned single-walled carbon nanotubes (SWCNT) that could revolutionize diverse commercial products ranging from rechargeable batteries, automotive parts and sporting goods to boat hulls and water filters.
Most CNT [carbon nanotube] production today is used in bulk composite materials and thin films, which rely on unorganized CNT architectures. For many uses, organized CNT architectures such as vertically aligned forests provide important advantages for exploiting the properties of individual CNTs in macroscopic systems.
“Robust synthesis of vertically-aligned carbon nanotubes at large scale is required to accelerate deployment of numerous cutting-edge devices to emerging commercial applications,” said LLNL scientist and lead author Francesco Fornasiero. “To address this need, we demonstrated that the structural characteristics of single-walled CNTs produced at wafer scale in a growth regime dominated by bulk diffusion of the gaseous carbon precursor are remarkably invariant over a broad range of process conditions.”
The team found that the vertically oriented SWCNTs retained very high quality when increasing precursor concentration (the initial carbon) up to 30-fold, the catalyst substrate area from 1 cm2 to 180 cm2, growth pressure from 20 to 790 Mbar and gas flowrates up to 8-fold.
LLNL scientists derived a kinetics model that shows the growth kinetics can be accelerated by using a lighter bath gas to aid precursor diffusion, and that byproduct formation, which becomes progressively more important at higher growth pressure, could be greatly mitigated by using a hydrogen-free growth environment. The model also indicates that appropriate choice of the CNT growth recipe and fluid dynamics conditions can increase the production throughput by 6-fold and the carbon conversion efficiency to higher than 90%.
“These model projections, along with the remarkably conserved structure of the CNT forests over a wide range of synthesis conditions, suggest that a bulk-diffusion-limited growth regime may facilitate preservation of vertically aligned CNT-based device performance during scale up,” said LLNL scientist and first author Sei Jin Park.
The team concluded that operating in a growth regime that is quantitatively described by a simple CNT growth kinetics model can facilitate process optimization and lead to a more rapid deployment of cutting-edge vertically-aligned CNT applications.
Applications include lithium-ion batteries, thermal interfaces, water purification, supercapacitors, breathable fabrics and sensors.
Nice to learn of this news, which is on the CBC (Canadian Broadcasting Corporation) news online website. From a December 13, 2022 news item provided by Associated Press (Note: the news item was updated to include general description and some Canadian content at about 12 pm PT) ,
Researchers at the Lawrence Livermore National Laboratory in California for the first time produced more energy in a fusion reaction than was used to ignite it, [emphasis mine] something called net energy gain, the Energy Department said.
Peter Behr’s December 13, 2022 article on Politico.com about the US Department of Energy’s big announcement also breaks the news,
The Department of Energy announced Tuesday [December 12, 2022] that its scientists have produced the first ever fusion reaction that yielded more energy than the reaction required, an essential step in the long path toward commercial fusion power, officials said.
The experiment Dec. 5 , at the Lawrence Livermore National Laboratory in California, took a few billionths of second. But laboratory leaders said today that it demonstrated for the first time that sustained fusion power is possible.
Behr explains what nuclear fusion is but first he touches on why scientists are so interested in the process, from his December 13, 2022 article,
In theory, nuclear fusion could produce massive amounts of energy without producing lost-lasting radioactive waste, or posing the risk of meltdowns. That’s unlike nuclear fission, which powers today’s reactors.
Fission results when radioactive atoms — most commonly uranium — are split by neutrons in controlled chain reactions, creating lighter atoms and large amounts of radiation and energy to produce electric power.
Fusion is the opposite process. In the most common approach, swirling hydrogen isotopes are forced together under tremendous heat to create helium and energy for power generation. This is the same process that powers the sun and other stars. But scientists have been trying since the mid-20th century to find a way to use it to generate power on Earth.
There are two main approaches to making fusion happen and I found a description for them in an October 2022 article about local company, General Fusion, by Nelson Bennett for Business in Vancouver magazine (paper version),
Most fusion companies are pursuing one of two approaches: Magnet [sic] or inertial confinement. General fusion is one of the few that is taking a more hybrid approach ¬ magnetic confinement with pulse compression.
Fusion occurs when smaller nuclei are fused together under tremendous force into larger nuclei, with a release of energy occurring in the form of neutrons. It’s what happens to stars when gravitational force creates extreme heat that turns on the fusion engine.
Replicating that in a machine requires some form of confinement to squeeze plasma ¬ a kind of super-hot fog of unbound positive and negative particles ¬ to the point where nuclei fuse.
One approach is inertial confinement, in which lasers are focused on a small capsule of heavy hydrogen fuel (deuterium and tritium) to create ignition. This takes a tremendous amount of energy, and the challenge for all fusion efforts is to get a sustained ignition that produces more energy than it takes to get ignition ¬ called net energy gain.
The other main approach is magnetic confinement, using powerful magnets in a machine called a tokomak to contain and squeeze plasma into a donut-shaped form called a torus.
General Fusion uses magnets to confine the plasma, but to get ignition it uses pistons arrayed around a spherical chamber to fire synchronously to essentially collapse the plasma on itself and spark ignition.
General Fusion’s machine uses liquid metal spinning inside a chamber that acts as a protective barrier between the hot plasma and the machine ¬ basically a sphere of plasma contained within a sphere of liquid metal. This protects the machine from damage.
The temperatures generated in fusion ¬ up to to 150 million degrees Celsius ¬ are five to six times hotter than the core of the sun, and can destroy machines that produce them. This makes durability a big challenge in any machine.
The Lawrence Livermore National Laboratory (LLNL) issued a December 13, 2022 news release, which provides more detail about their pioneering work, Note: I have changed the order of the paragraphs but all of this is from the news release,
Fusion is the process by which two light nuclei combine to form a single heavier nucleus, releasing a large amount of energy. In the 1960s, a group of pioneering scientists at LLNL hypothesized that lasers could be used to induce fusion in a laboratory setting. Led by physicist John Nuckolls, who later served as LLNL director from 1988 to 1994, this revolutionary idea became inertial confinement fusion, kicking off more than 60 years of research and development in lasers, optics, diagnostics, target fabrication, computer modeling and simulation and experimental design.
To pursue this concept, LLNL built a series of increasingly powerful laser systems, leading to the creation of NIF [National Ignition Facility], the world’s largest and most energetic laser system. NIF — located at LLNL in Livermore, California — is the size of a sports stadium and uses powerful laser beams to create temperatures and pressures like those in the cores of stars and giant planets, and inside exploding nuclear weapons.
LLNL’s experiment surpassed the fusion threshold by delivering 2.05 megajoules (MJ) of energy to the target, resulting in 3.15 MJ of fusion energy output, demonstrating for the first time a most fundamental science basis for inertial fusion energy (IFE). Many advanced science and technology developments are still needed to achieve simple, affordable IFE to power homes and businesses, and DOE is currently restarting a broad-based, coordinated IFE program in the United States. Combined with private-sector investment, there is a lot of momentum to drive rapid progress toward fusion commercialization.
If you want to see some really excited comments from scientists just read the LLNL’s December 13, 2022 news release. Even the news release’s banner is exuberant,
Fearful that China might wind up dominating fusion energy in the second half of this century, Congress in 2020 told DOE [Department of Energy] to begin funding development of a utility-scale fusion pilot plant that could deliver at least 50 megawatts of power to the U.S. grid.
In September , DOE invited private companies to apply for an initial $50 million in research grants to help fund development of detailed pilot plant plans.
“We’re seeking strong partnerships between DOE and the private sector,” a senior DOE official told POLITICO’s E&E News recently. The official was not willing to speak on the record, saying the grant process is ongoing and confidential.
As the competition proceeds, DOE will set technical milestones or requirements, challenging the teams to show how critical engineering challenges will be overcome. DOE’s goal is “hopefully to enable a fusion pilot to operate in the early 2030s,” the official added.
At least 15 U.S. and foreign fusion companies have submitted requests for an initial total of $50 million in pilot plant grants, and some of them are pursuing the laser-ignition fusion process that Lawrence Livermore has pioneered, said Holland. He did not name the companies because the competition is confidential.
I wonder if General Fusion whose CEO (Chief Executive Officer) Greg Twinney declared, “Commercializing fusion energy is within reach, and General Fusion is ready to deliver it to the grid by the 2030s …” (in a December 12, 2022 company press release) is part of the US competition.
I noticed that General Fusion lists this at the end of the press release,
… Founded in 2002, we are headquartered in Vancouver, Canada, with additional centers co-located with internationally recognized fusion research laboratories near London, U.K., and Oak Ridge, Tennessee, U.S.A.
The Oak Ridge National Laboratory (ORNL), like the LLNL, is a US Department of Energy research facility.
As for General Fusion’s London connection, I have more about that in my October 28, 2022 posting “Overview of fusion energy scene,” which includes General Fusion’s then latest news about a commercialization agreement with the UKAEA (UK Atomic Energy Authority) and a ‘fusion’ video by rapper Baba Brinkman along with the overview.
It’s funny how you think you know something and then realize you don’t. I’ve been hearing about cold fusion/fusion energy for years but never really understood what the term meant. So, this post includes an explanation, as well as, an overview, and a Cold Fusion Rap to ‘wrap’ it all up. (Sometimes I cannot resist a pun.)
Fusion energy explanation (1)
The Massachusetts Institute of Technology (MIT) has a Climate Portal where fusion energy is explained,
Fusion energy is the source of energy at the center of stars, including our own sun. Stars, like most of the universe, are made up of hydrogen, the simplest and most abundant element in the universe, created during the big bang. The center of a star is so hot and so dense that the immense pressure forces hydrogen atoms together. These atoms are forced together so strongly that they create new atoms entirely—helium atoms—and release a staggering amount of energy in the process. This energy is called fusion energy.
More energy than chemical energy
Fusion energy, like fossil fuels, is a form of stored energy. But fusion can create 20 to 100 million times more energy than the chemical reaction of a fossil fuel. Most of the mass of an atom, 99.9 percent, is contained at an atom’s center—inside of its nucleus. The ratio of this matter to the empty space in an atom is almost exactly the same ratio of how much energy you release when you manipulate the nucleus. In contrast, a chemical reaction, such as burning coal, rearranges the atoms through heat, but doesn’t alter the atoms themselves, so we don’t get as much energy.
Making fusion energy
For scientists, making fusion energy means recreating the conditions of stars, starting with plasma. Plasma is the fourth state of matter, after solids, liquids and gases. Ice is an example of a solid. When heated up, it becomes a liquid. Place that liquid in a pot on the stove, and it becomes a gas (steam). If you take that gas and continue to make it hotter, at around 10,000 degrees Fahrenheit (~6,000 Kelvin), it will change from a gas to the next phase of matter: plasma. Ninety-nine percent of the mass in the universe is in the plasma state, since almost the entire mass of the universe is in super hot stars that exist as plasma.
To make fusion energy, scientists must first build a steel chamber and create a vacuum, like in outer space. The next step is to add hydrogen gas. The gas particles are charged to produce an electric current and then surrounded and contained with an electromagnetic force; the hydrogen is now a plasma. This plasma is then heated to about 100 million degrees and fusion energy is released.
Fusion energy explanation (2)
A Vancouver-based company, General Fusion, offers an explanation of how they have approached making fusion energy a reality,
Today [October 17, 2022], General Fusion and the UKAEA kick off projects to advance the commercialization of magnetized target fusion energy as part of an important collaborative agreement. With these unique projects, General Fusion will benefit from the vast experience of the UKAEA’s team. The results will hone the design of General Fusion’s demonstration machine being built at the Culham Campus, part of the thriving UK fusion cluster. Ultimately, the company expects the projects will support its efforts to provide low-cost and low-carbon energy to the electricity grid.
General Fusion’s approach to fusion maximizes the reapplication of existing industrialized technologies, bypassing the need for expensive superconducting magnets, significant new materials, or high-power lasers. The demonstration machine will create fusion conditions in a power-plant-relevant environment, confirming the performance and economics of the company’s technology.
“The leading-edge fusion researchers at UKAEA have proven experience building, commissioning, and successfully operating large fusion machines,” said Greg Twinney, Chief Executive Officer, General Fusion. “Partnering with UKAEA’s incredible team will fast-track work to advance our technology and achieve our mission of delivering affordable commercial fusion power to the world.”
“Fusion energy is one of the greatest scientific and engineering quests of our time,” said Ian Chapman, UKAEA CEO. “This collaboration will enable General Fusion to benefit from the ground-breaking research being done in the UK and supports our shared aims of making fusion part of the world’s future energy mix for generations to come.”
I first wrote about General Fusion in a December 2, 2011 posting titled: Burnaby-based company (Canada) challenges fossil fuel consumption with nuclear fusion. (For those unfamiliar with the Vancouver area, there’s the city of Vancouver and there’s Vancouver Metro, which includes the city of Vancouver and others in the region. Burnaby is part of Metro Vancouver; General Fusion is moving to Sea Island (near Vancouver Airport), in Richmond, which is also in Metro Vancouver.) Kenneth Chan’s October 20, 2021 article for the Daily Hive gives more detail about General Fusion’s new facilities (Note: A link has been removed),
The new facility will span two buildings at 6020 and 6082 Russ Baker Way, near YVR’s [Vancouver Airport] South Terminal. This includes a larger building previously used for aircraft engine maintenance and repair.
The relocation process could start before the end of 2021, allowing the company to more than quadruple its workforce over the coming years. Currently, it employs about 140 people.
The Sea Island [in Richmond] facility will house its corporate offices, primary fusion technology development division, and many of its engineering laboratories. This new facility provides General Fusion with the ability to build a new demonstration prototype to support the commercialization of its magnetized target fusion technology.
As of the date of this posting, I have not been able to confirm the move. The company’s Contact webpage lists an address in Burnaby, BC for its headquarters.
With energy prices on the rise, along with demands for energy independence and an urgent need for carbon-free power, plans to walk away from nuclear energy are now being revised in Japan, South Korea, and even Germany. Last month, Europe announced green bonds for nuclear, and the U.S., thanks to the Inflation Reduction Act, will soon devote millions to new nuclear designs, incentives for nuclear production and domestic uranium mining, and, after years of paucity in funding, cash for fusion.
The new investment comes as fusion—long considered a pipe dream—has attracted real money from big venture capital and big companies, who are increasingly betting that abundant, cheap, clean nuclear will be a multi-trillion dollar industry. Last year, investors like Bill Gates and Jeff Bezos injected a record $3.4 billion into firms working on the technology, according to Pitchbook. One fusion firm, Seattle-based Helion, raised a record $500 million from Sam Altman and Peter Thiel. That money has certainly supercharged the nuclear sector: The Fusion Industry Association says that at least 33 different companies were now pursuing nuclear fusion, and predicted that fusion would be connected to the energy grid sometime in the 2030s.
… What’s not a joke is that we have about zero years to stop powering our civilization with earth-warming energy. The challenge with fusion is to achieve net energy gain, where the energy produced by a fusion reaction exceeds the energy used to make it. One milestone came quietly this month, when a team of researchers at the National Ignition Facility at Lawrence Livermore National Lab in California announced that an experiment last year had yielded over 1.3 megajoules (MJ) of energy, setting a new world record for energy yield for a nuclear fusion experiment. The experiment also achieved scientific ignition for the first time in history: after applying enough heat using an arsenal of lasers, the plasma became self-heating. (Researchers have since been trying to replicate the result, so far without success.)
On a growing campus an hour outside of Boston, the MIT spinoff Commonwealth Fusion Systems is building their first machine, SPARC, with a goal of producing power by 2025. “You’ll push a button,” CEO and cofounder Bob Mumgaard told the Khosla Ventures CEO Summit this summer, “and for the first time on earth you will make more power out than in from a fusion plasma. That’s about 200 million degrees—you know, cooling towers will have a bunch of steam go out of them—and you let your finger off the button and it will stop, and you push the button again and it will go.” With an explosion in funding from investors including Khosla, Bill Gates, George Soros, Emerson Collective and Google to name a few—they raised $1.8 billion last year alone—CFS hopes to start operating a prototype in 2025.
Like the three-decade-old ITER project in France, set for operation in 2025, Commonwealth and many other companies will try to reach net energy gain using a machine called a tokamak, a bagel-shaped device filled with super-hot plasma, heated to about 150 million degrees, within which hydrogen atoms can fuse and release energy. To control that hot plasma, you need to build a very powerful magnetic field. Commonwealth’s breakthrough was tape—specifically, a high-temperature-superconducting steel tape coated with a compound called yttrium-barium-copper oxide. When a prototype was first made commercially available in 2009, Dennis Whyte, director of MIT’s Plasma Science and Fusion Center, ordered as much as he could. With Mumgaard and a team of students, his lab used coils of the stuff to build a new kind of superconducting magnet, and a prototype reactor named ARC, after Tony Stark’s energy source. Commonwealth was born in 2015.
Southern California-based TAE Technologies has raised a whopping $1.2 billion since it was founded in 1998, and $250 million in its latest round. The round, announced in July, was led by Chevron’s venture arm, Google, and Sumitomo, a Tokyo-based holding company that aims to deploy fusion power in the Asia-Pacific market. TAE’s approach, which involves creating a fusion reaction at incredibly high heat, has a key advantage. Whereas ITER uses the hydrogen isotopes deuterium and tritium, an extremely rare element that must be specially created from lithium—and that produces as a byproduct radioactive-free neutrons—TAE’s linear reactor is completely non-radioactive, because it relies on hydrogen and boron, two abundant, naturally-occurring elements that react to produce only helium.
General Atomics, of San Diego, California, has the largest tokamak in the U.S. Its powerful magnetic chamber, called the DIII-D National Fusion Facility, or just “D-three-D,” now features a Toroidal Field Reversing Switch, which allows for the redirection of 120,000 amps of the current that power the primary magnetic field. It’s the only tokamak in the world that allows researchers to switch directions of the magnetic fields in minutes rather than hours. Another new upgrade, a traveling-wave antenna, allows physicists to inject high-powered “helicon” radio waves into DIII-D plasmas so fusion reactions occur much more powerfully and efficiently.
“We’ve got new tools for flexibility and new tools to help us figure out how to make that fusion plasma just keep going,” Richard Buttery, director of the project, told the San Diego Union-Tribune in January. The company is also behind eight of the magnet modules at the heart of the ITER facility, including its wild Central Solenoid — the world’s most powerful magnet — in a kind of scaled up version of the California machine.
But like an awful lot in fusion, ITER has been hampered by cost overruns and delays, with “first plasma” not expected to occur in 2025 as previously expected due to global pandemic-related disruptions. Some have complained that the money going to ITER has distracted from other more practical energy projects—the latest price tag is $22 billion—and others doubt if the project can ever produce net energy gain.
Based in Canada, General Fusion is backed by Jeff Bezos and building on technology originally developed by the U.S. Navy and explored by Russian scientists for potential use in weapons. Inside the machine, molten metal is spun to create a cavity, and pumped with pistons that push the metal inward to form a sphere. Hydrogen, heated to super-hot temperatures and held in place by a magnetic field, fills the sphere to create the reaction. Heat transferred to the metal can be turned into steam to drive a turbine and generate electricity. As former CEO Christofer Mowry told Fast Company last year, “to re-create a piece of the sun on Earth, as you can imagine, is very, very challenging.” Like many fusion companies, GF depends on modern supercomputers and advanced modeling and computational techniques to understand the science of plasma physics, as well as modern manufacturing technologies and materials.
“That’s really opened the door not just to being able to make fusion work but to make it work in a practical way,” Mowry said. This has been difficult to make work, but with a demonstration center it announced last year in Culham, England, GF isn’t aiming to generate electricity but to gather the data needed to later build a commercial pilot plant that could—and to generate more interest in fusion.
Magneto-Intertial Fusion Technologies, or MIFTI, of Tustin, Calif., founded by researchers from the University of California, Irvine, is developing a reactor that uses what’s known as a Staged Z-Pinch approach. A Z-Pinch design heats, confines, and compresses plasma using an intense, pulsed electrical current to generate a magnetic field that could reduce instabilities in the plasma, allowing fusion to persist for longer periods of time. But only recently have MIFTI’s scientists been able to overcome the instability problems, the company says, thanks to software made available to them at UC-Irvine by the U.S. Air Force. …
Princeton Fusion Systems of Plainsboro, New Jersey, is a small business focused on developing small, clean fusion reactors for both terrestrial and space applications. A spinoff of Princeton Satellite Systems, which specializes in spacecraft control, the company’s Princeton FRC reactor is built upon 15 years of research at the Princeton Plasma Physics Laboratory, funded primarily by the U.S. DOE and NASA, and is designed to eventually provide between 1 and 10 megawatts of power in off-grid locations and in modular power plants, “from remote industrial applications to emergency power after natural disasters to off-world bases on the moon or Mars.” The concept uses radio-frequency electromagnetic fields to generates and sustain a plasma formation called a Field-Reversed Configuration (FRC) inside a strong magnetic bottle. …
Tokamak Energy, a U.K.-based company named after the popular fusion device, announced in July that its ST-40 tokamak reactor had reached the 100 million Celsius threshold for commercially viable nuclear fusion. The achievement was made possible by a proprietary design built on a spherical, rather than donut, shape. This means that the magnets are closer to the plasma stream, allowing for smaller and cheaper magnets to create even stronger magnetic fields. …
Based in Pasadena, California, Helicity Space is developing a propulsion and power technology based on a specialized magneto inertial fusion concept. The system, a spin on what fellow fusion engineer, Seattle-based Helion is doing, appears to use twisted compression coils, like a braided rope, to achieve a known phenomenon called the Magnetic Helicity. … According to ZoomInfo and Linkedin, Helicity has over $4 million in funding and up to 10 employees, all aimed, the company says, at “enabling humanity’s access to the solar system, with a Helicity Drive-powered flight to Mars expected to take two months, without planetary alignment.”
ITER (International Thermonuclear Experimental Reactor), meaning “the way” or “the path” in Latin and mentioned in Pasternak’s article, dates its history with *fusion back to about 1978 when cold fusion was the ‘hot’ topic*. (You can read more here in the ITER Wikipedia entry.)
For more about the various approaches to fusion energy, read Pasternack’s August 17, 2022 article (The frontrunners in the trillion-dollar race for limitless fusion power) provides details. I wish there had been a little more about efforts in Japan and South Korea and other parts of the world. Pasternak’s singular focus on the US with a little of Canada and the UK seemingly thrown into the mix to provide an international flavour seems a little myopic.
In an August 30, 2022 Baba Brinkman announcement (received via email) which gave an extensive update of Brinkman’s activities, there was this,
And the other new topic, which was surprisingly fun to explore, is cold fusion also known as “Low Energy Nuclear Reactions” which you may or may not have a strong opinion about, but if you do I imagine you probably think the technology is either bunk or destined to save the world.
That makes for an interesting topic to explore in rap songs! And fortunately last month I had the pleasure of performing for the cream of the LENR crop at the 24th International Conference on Cold Fusion, including rap ups and two new songs about the field, one very celebratory (for the insiders), and one cautiously optimistic (as an outreach tool).
Here’s one of the rap videos mentioned in Brinkman’s email,
*December 13, 2022: Sentence changed from “ITER (International Thermonuclear Experimental Reactor), meaning “the way” or “the path” in Latin and mentioned in Pasternak’s article, dates its history with fusion back to about 1978 when cold fusion was the ‘hot’ topic.” to “ITER (International Thermonuclear Experimental Reactor), meaning “the way” or “the path” in Latin and mentioned in Pasternak’s article, dates its history with fusion back to about 1978 when cold fusion was the ‘hot’ topic.”
** ‘Pasternak’ corrected to ‘Pasternack” and ‘in Fast Company’ added on December 29, 2022
In discussions about water desalination and carbon nanomaterials, it’s graphene that’s usually mentioned these days. By contrast, scientists from the US Department of Energy’s Lawrence Livermore National Laboratory (LLNL) have turned to carbon nanotubes,
There are two news items about the work at LLNL on ScienceDaily, this first one originated by the American Association for the Advancement of Science (AAAS) offers a succinct summary of the work (from an August 24, 2017 news item on ScienceDaily,
At just the right size, carbon nanotubes can filter water with better efficiency than biological proteins, a new study reveals. The results could pave the way to new water filtration systems, at a time when demands for fresh water pose a global threat to sustainable development.
A class of biological proteins, called aquaporins, is able to effectively filter water, yet scientists have not been able to manufacture scalable systems that mimic this ability. Aquaporins usually exhibit channels for filtering water molecules at a narrow width of 0.3 nanometers, which forces the water molecules into a single-file chain.
Here, Ramya H. Tunuguntla and colleagues experimented with nanotubes of different widths to see which ones are best for filtering water. Intriguingly, they found that carbon nanotubes with a width of 0.8 nanometers outperformed aquaporins in filtering efficiency by a factor of six.
These narrow carbon nanotube porins (nCNTPs) were still slim enough to force the water molecules into a single-file chain. The researchers attribute the differences between aquaporins and nCNTPS to differences in hydrogen bonding — whereas pore-lining residues in aquaporins can donate or accept H bonds to incoming water molecules, the walls of CNTPs cannot form H bonds, permitting unimpeded water flow.
The nCNTPs in this study maintained permeability exceeding that of typical saltwater, only diminishing at very high salt concentrations. Lastly, the team found that by changing the charges at the mouth of the nanotube, they can alter the ion selectivity. This advancement is highlighted in a Perspective [in Science magazine] by Zuzanna Siwy and Francesco Fornasiero.
Lawrence Livermore scientists, in collaboration with researchers at Northeastern University, have developed carbon nanotube pores that can exclude salt from seawater. The team also found that water permeability in carbon nanotubes (CNTs) with diameters smaller than a nanometer (0.8 nm) exceeds that of wider carbon nanotubes by an order of magnitude.
The nanotubes, hollow structures made of carbon atoms in a unique arrangement, are more than 50,000 times thinner than a human hair. The super smooth inner surface of the nanotube is responsible for their remarkably high water permeability, while the tiny pore size blocks larger salt ions.
There’s a rather lovely illustration for this work,
An artist’s depiction of the promise of carbon nanotube porins for desalination. The image depicts a stylized carbon nanotube pipe that delivers clean desalinated water from the ocean to a kitchen tap. Image by Ryan Chen/LLNL
Increasing demands for fresh water pose a global threat to sustainable development, resulting in water scarcity for 4 billion people. Current water purification technologies can benefit from the development of membranes with specialized pores that mimic highly efficient and water selective biological proteins.
“We found that carbon nanotubes with diameters smaller than a nanometer bear a key structural feature that enables enhanced transport. The narrow hydrophobic channel forces water to translocate in a single-file arrangement, a phenomenon similar to that found in the most efficient biological water transporters,” said Ramya Tunuguntla, an LLNL postdoctoral researcher and co-author of the manuscript appearing in the Aug. 24 edition of Science.
Computer simulations and experimental studies of water transport through CNTs with diameters larger than 1 nm showed enhanced water flow, but did not match the transport efficiency of biological proteins and did not separate salt efficiently, especially at higher salinities. The key breakthrough achieved by the LLNL team was to use smaller-diameter nanotubes that delivered the required boost in performance.
“These studies revealed the details of the water transport mechanism and showed that rational manipulation of these parameters can enhance pore efficiency,” said Meni Wanunu, a physics professor at Northeastern University and co-author on the study.
“Carbon nanotubes are a unique platform for studying molecular transport and nanofluidics,” said Alex Noy, LLNL principal investigator on the CNT project and a senior author on the paper. “Their sub-nanometer size, atomically smooth surfaces and similarity to cellular water transport channels make them exceptionally suited for this purpose, and it is very exciting to make a synthetic water channel that performs better than nature’s own.”
This discovery by the LLNL scientists and their colleagues has clear implications for the next generation of water purification technologies and will spur a renewed interest in development of the next generation of high-flux membranes.
Earth is 70 percent water, but only a tiny portion—0.007 percent—is available to drink.
As potable water sources dwindle, global population increases every year. One potential solution to quenching the planet’s thirst is through desalinization—the process of removing salt from seawater. While tantalizing, this approach has always been too expensive and energy intensive for large-scale feasibility.
Now, researchers from Northeastern have made a discovery that could change that, making desalinization easier, faster and cheaper than ever before. In a paper published Thursday [August 24, 2017] in Science, the group describes how carbon nanotubes of a certain size act as the perfect filter for salt—the smallest and most abundant water contaminant.
Filtering water is tricky because water molecules want to stick together. The “H” in H2O is hydrogen, and hydrogen bonds are strong, requiring a lot of energy to separate. Water tends to bulk up and resist being filtered. But nanotubes do it rapidly, with ease.
A carbon nanotube is like an impossibly small rolled up sheet of paper, about a nanometer in diameter. For comparison, the diameter of a human hair is 50 to 70 micrometers—50,000 times wider. The tube’s miniscule size, exactly 0.8 nm, only allows one water molecule to pass through at a time. This single-file lineup disrupts the hydrogen bonds, so water can be pushed through the tubes at an accelerated pace, with no bulking.
“You can imagine if you’re a group of people trying to run through the hallway holding hands, it’s going to be a lot slower than running through the hallway single-file,” said co-author Meni Wanunu, associate professor of physics at Northeastern. Wanunu and post doctoral student Robert Henley collaborated with scientists at the Lawrence Livermore National Laboratory in California to conduct the research.
Scientists led by Aleksandr Noy at Lawrence Livermore discovered last year  that carbon nanotubes were an ideal channel for proton transport. For this new study, Henley brought expertise and technology from Wanunu’s Nanoscale Biophysics Lab to Noy’s lab, and together they took the research one step further.
In addition to being precisely the right size for passing single water molecules, carbon nanotubes have a negative electric charge. This causes them to reject anything with the same charge, like the negative ions in salt, as well as other unwanted particles.
“While salt has a hard time passing through because of the charge, water is a neutral molecule and passes through easily,” Wanunu said. Scientists in Noy’s lab had theorized that carbon nanotubes could be designed for specific ion selectivity, but they didn’t have a reliable system of measurement. Luckily, “That’s the bread and butter of what we do in Meni’s lab,” Henley said. “It created a nice symbiotic relationship.”
“Robert brought the cutting-edge measurement and design capabilities of Wanunu’s group to my lab, and he was indispensable in developing a new platform that we used to measure the ion selectivity of the nanotubes,” Noy said.
The result is a novel system that could have major implications for the future of water security. The study showed that carbon nanotubes are better at desalinization than any other existing method— natural or man-made.
To keep their momentum going, the two labs have partnered with a leading water purification organization based in Israel. And the group was recently awarded a National Science Foundation/Binational Science Foundation grant to conduct further studies and develop water filtration platforms based on their new method. As they continue the research, the researchers hope to start programs where students can learn the latest on water filtration technology—with the goal of increasing that 0.007 percent.
As is usual in these cases there’s a fair degree of repetition but there’s always at least one nugget of new information, in this case, a link to Israel. As I noted many times, the Middle East is experiencing serious water issues. My most recent ‘water and the Middle East’ piece is an August 21, 2017 post about rainmaking at the Masdar Institute in United Arab Emirates. Approximately 50% of the way down the posting, I mention Israel and Palestine’s conflict over water.
This is the second IBM computer announcement I’ve stumbled onto within the last 4 weeks or so, which seems like a veritable deluge given the last time I wrote about IBM’s computing efforts was in an Oct. 8, 2015 posting about carbon nanotubes,. I believe that up until now that was my most recent posting about IBM and computers.
IBM (NYSE: IBM) and the U.S. Air Force Research Laboratory (AFRL) today [June 23, 2017] announced they are collaborating on a first-of-a-kind brain-inspired supercomputing system powered by a 64-chip array of the IBM TrueNorth Neurosynaptic System. The scalable platform IBM is building for AFRL will feature an end-to-end software ecosystem designed to enable deep neural-network learning and information discovery. The system’s advanced pattern recognition and sensory processing power will be the equivalent of 64 million neurons and 16 billion synapses, while the processor component will consume the energy equivalent of a dim light bulb – a mere 10 watts to power.
IBM researchers believe the brain-inspired, neural network design of TrueNorth will be far more efficient for pattern recognition and integrated sensory processing than systems powered by conventional chips. AFRL is investigating applications of the system in embedded, mobile, autonomous settings where, today, size, weight and power (SWaP) are key limiting factors.
The IBM TrueNorth Neurosynaptic System can efficiently convert data (such as images, video, audio and text) from multiple, distributed sensors into symbols in real time. AFRL will combine this “right-brain” perception capability of the system with the “left-brain” symbol processing capabilities of conventional computer systems. The large scale of the system will enable both “data parallelism” where multiple data sources can be run in parallel against the same neural network and “model parallelism” where independent neural networks form an ensemble that can be run in parallel on the same data.
“AFRL was the earliest adopter of TrueNorth for converting data into decisions,” said Daniel S. Goddard, director, information directorate, U.S. Air Force Research Lab. “The new neurosynaptic system will be used to enable new computing capabilities important to AFRL’s mission to explore, prototype and demonstrate high-impact, game-changing technologies that enable the Air Force and the nation to maintain its superior technical advantage.”
“The evolution of the IBM TrueNorth Neurosynaptic System is a solid proof point in our quest to lead the industry in AI hardware innovation,” said Dharmendra S. Modha, IBM Fellow, chief scientist, brain-inspired computing, IBM Research – Almaden. “Over the last six years, IBM has expanded the number of neurons per system from 256 to more than 64 million – an 800 percent annual increase over six years.’’
The system fits in a 4U-high (7”) space in a standard server rack and eight such systems will enable the unprecedented scale of 512 million neurons per rack. A single processor in the system consists of 5.4 billion transistors organized into 4,096 neural cores creating an array of 1 million digital neurons that communicate with one another via 256 million electrical synapses. For CIFAR-100 dataset, TrueNorth achieves near state-of-the-art accuracy, while running at >1,500 frames/s and using 200 mW (effectively >7,000 frames/s per Watt) – orders of magnitude lower speed and energy than a conventional computer running inference on the same neural network.
The IBM TrueNorth Neurosynaptic System was originally developed under the auspices of Defense Advanced Research Projects Agency’s (DARPA) Systems of Neuromorphic Adaptive Plastic Scalable Electronics (SyNAPSE) program in collaboration with Cornell University. In 2016, the TrueNorth Team received the inaugural Misha Mahowald Prize for Neuromorphic Engineering and TrueNorth was accepted into the Computer History Museum. Research with TrueNorth is currently being performed by more than 40 universities, government labs, and industrial partners on five continents.
There is an IBM video accompanying this news release, which seems more promotional than informational,
The IBM scientist featured in the video has a Dec. 19, 2016 posting on an IBM research blog which provides context for this collaboration with AFRL,
2016 was a big year for brain-inspired computing. My team and I proved in our paper “Convolutional networks for fast, energy-efficient neuromorphic computing” that the value of this breakthrough is that it can perform neural network inference at unprecedented ultra-low energy consumption. Simply stated, our TrueNorth chip’s non-von Neumann architecture mimics the brain’s neural architecture — giving it unprecedented efficiency and scalability over today’s computers.
The brain-inspired TrueNorth processor [is] a 70mW reconfigurable silicon chip with 1 million neurons, 256 million synapses, and 4096 parallel and distributed neural cores. For systems, we present a scale-out system loosely coupling 16 single-chip boards and a scale-up system tightly integrating 16 chips in a 4´4 configuration by exploiting TrueNorth’s native tiling.
TrueNorth, once loaded with a neural network model, can be used in real-time as a sensory streaming inference engine, performing rapid and accurate classifications while using minimal energy. TrueNorth’s 1 million neurons consume only 70 mW, which is like having a neurosynaptic supercomputer the size of a postage stamp that can run on a smartphone battery for a week.
Recently, in collaboration with Lawrence Livermore National Laboratory, U.S. Air Force Research Laboratory, and U.S. Army Research Laboratory, we published our fifth paper at IEEE’s prestigious Supercomputing 2016 conference that summarizes the results of the team’s 12.5-year journey (see the associated graphic) to unlock this value proposition. [keep scrolling for the graphic]
Applying the mind of a chip
Three of our partners, U.S. Army Research Lab, U.S. Air Force Research Lab and Lawrence Livermore National Lab, contributed sections to the Supercomputing paper each showcasing a different TrueNorth system, as summarized by my colleagues Jun Sawada, Brian Taba, Pallab Datta, and Ben Shaw:
U.S. Army Research Lab (ARL) prototyped a computational offloading scheme to illustrate how TrueNorth’s low power profile enables computation at the point of data collection. Using the single-chip NS1e board and an Android tablet, ARL researchers created a demonstration system that allows visitors to their lab to hand write arithmetic expressions on the tablet, with handwriting streamed to the NS1e for character recognition, and recognized characters sent back to the tablet for arithmetic calculation.
Of course, the point here is not to make a handwriting calculator, it is to show how TrueNorth’s low power and real time pattern recognition might be deployed at the point of data collection to reduce latency, complexity and transmission bandwidth, as well as back-end data storage requirements in distributed systems.
U.S. Air Force Research Lab (AFRL) contributed another prototype application utilizing a TrueNorth scale-out system to perform a data-parallel text extraction and recognition task. In this application, an image of a document is segmented into individual characters that are streamed to AFRL’s NS1e16 TrueNorth system for parallel character recognition. Classification results are then sent to an inference-based natural language model to reconstruct words and sentences. This system can process 16,000 characters per second! AFRL plans to implement the word and sentence inference algorithms on TrueNorth, as well.
Lawrence Livermore National Lab (LLNL) has a 16-chip NS16e scale-up system to explore the potential of post-von Neumann computation through larger neural models and more complex algorithms, enabled by the native tiling characteristics of the TrueNorth chip. For the Supercomputing paper, they contributed a single-chip application performing in-situ process monitoring in an additive manufacturing process. LLNL trained a TrueNorth network to recognize seven classes related to track weld quality in welds produced by a selective laser melting machine. Real-time weld quality determination allows for closed-loop process improvement and immediate rejection of defective parts. This is one of several applications LLNL is developing to showcase TrueNorth as a scalable platform for low-power, real-time inference.
[downloaded from https://www.ibm.com/blogs/research/2016/12/the-brains-architecture-efficiency-on-a-chip/] Courtesy: IBM
I gather this 2017 announcement is the latest milestone on the TrueNorth journey.
This research may help to commercialize use of carbon nanotubes (CNTs), a ‘magical’ nanoscale material with great promise and great difficulties (standardizing production being one of the main difficulties). A Feb. 10, 2017 news item on phys.org describes how researchers at the Lawrence Livermore National Laboratory (LLNL) and other collaborators have recorded carbon nanotubes self-organizing,
For the first time, Lawrence Livermore National Laboratory scientists and collaborators have captured a movie of how large populations of carbon nanotubes grow and align themselves.
Understanding how carbon nanotubes (CNT) nucleate, grow and self-organize to form macroscale materials is critical for application-oriented design of next-generation supercapacitors, electronic interconnects, separation membranes and advanced yarns and fabrics.
New research by LLNL scientist Eric Meshot and colleagues from Brookhaven National Laboratory (link is external) (BNL) and Massachusetts Institute of Technology (link is external) (MIT) has demonstrated direct visualization of collective nucleation and self-organization of aligned carbon nanotube films inside of an environmental transmission electron microscope (ETEM).
In a pair of studies reported in recent issues of Chemistry of Materials (link is external) and ACS Nano (link is external), the researchers leveraged a state-of-the-art kilohertz camera in an aberration-correction ETEM at BNL to capture the inherently rapid processes that govern the growth of these exciting nanostructures.
Among other phenomena discovered, the researchers are the first to provide direct proof of how mechanical competition among neighboring carbon nanotubes can simultaneously promote self-alignment while also frustrating and limiting growth.
“This knowledge may enable new pathways toward mitigating self-termination and promoting growth of ultra-dense and aligned carbon nanotube materials, which would directly impact several application spaces, some of which are being pursued here at the Laboratory,” Meshot said.
Meshot has led the CNT synthesis development at LLNL for several projects, including those supported by the Laboratory Directed Research and Development (LDRD) program and the Defense Threat Reduction Agency (link is external) (DTRA) that use CNTs as fluidic nanochannels for applications ranging from single-molecule detection to macroscale membranes for breathable and protective garments.
Here’s a link to and a citation for the both of the papers mentioned in the news release,
They say it’s provisionally but I suspect it would take an act of god for a change in the proposed names. From a June 8, 2016 blog posting (scroll down about 25% of the way) on the International Union of Pure and Applied Chemistry (IUPAC) website,
IUPAC is naming the four new elements nihonium, moscovium, tennessine, and oganesson
Following earlier reports that the claims for discovery of these elements have been fulfilled [1, 2], the discoverers have been invited to propose names and the following are now disclosed for public review:
Nihonium and symbol Nh, for the element 113,
Moscovium and symbol Mc, for the element 115,
Tennessine and symbol Ts, for the element 117, and
Oganesson and symbol Og, for the element 118.
The IUPAC Inorganic Chemistry Division has reviewed and considered these proposals and recommends these for acceptance. A five-month public review is now set, expiring 8 November 2016, prior to the formal approval by the IUPAC Council.
I can’t figure out how someone from the public might offer a comment about the names.
There’s more from the posting about what kinds of names are acceptable and how the names in this set of four were arrived at,
The guidelines for the naming the elements were recently revised  and shared with the discoverers to assist in their proposals. Keeping with tradition, newly discovered elements can be named after:
(a) a mythological concept or character (including an astronomical object),
(b) a mineral or similar substance,
(c) a place, or geographical region,
(d) a property of the element, or
(e) a scientist.
The names of all new elements in general would have an ending that reflects and maintains historical and chemical consistency. This would be in general “-ium” for elements belonging to groups 1-16, “-ine” for elements of group 17 and “-on” for elements of group 18. Finally, the names for new chemical elements in English should allow proper translation into other major languages.
For the element with atomic number 113 the discoverers at RIKEN Nishina Center for Accelerator-Based Science (Japan) proposed the name nihonium and the symbol Nh. Nihon is one of the two ways to say “Japan” in Japanese, and literally mean “the Land of Rising Sun”. The name is proposed to make a direct connection to the nation where the element was discovered. Element 113 is the first element to have been discovered in an Asian country. While presenting this proposal, the team headed by Professor Kosuke Morita pays homage to the trailblazing work by Masataka Ogawa done in 1908 surrounding the discovery of element 43. The team also hopes that pride and faith in science will displace the lost trust of those who suffered from the 2011 Fukushima nuclear disaster.
For the element with atomic number 115 the name proposed is moscovium with the symbol Mc and for element with atomic number 117, the name proposed is tennessine with the symbol Ts. These are in line with tradition honoring a place or geographical region and are proposed jointly by the discoverers at the Joint Institute for Nuclear Research, Dubna (Russia), Oak Ridge National Laboratory (USA), Vanderbilt University (USA) and Lawrence Livermore National Laboratory (USA).
Moscovium is in recognition of the Moscow region and honors the ancient Russian land that is the home of the Joint Institute for Nuclear Research, where the discovery experiments were conducted using the Dubna Gas-Filled Recoil Separator in combination with the heavy ion accelerator capabilities of the Flerov Laboratory of Nuclear Reactions.
Tennessine is in recognition of the contribution of the Tennessee region, including Oak Ridge National Laboratory, Vanderbilt University, and the University of Tennessee at Knoxville, to superheavy element research, including the production and chemical separation of unique actinide target materials for superheavy element synthesis at ORNL’s High Flux Isotope Reactor (HFIR) and Radiochemical Engineering Development Center (REDC).
For the element with atomic number 118 the collaborating teams of discoverers at the Joint Institute for Nuclear Research, Dubna (Russia) and Lawrence Livermore National Laboratory (USA) proposed the name oganesson and symbol Og. The proposal is in line with the tradition of honoring a scientist and recognizes Professor Yuri Oganessian (born 1933) for his pioneering contributions to transactinoid elements research. His many achievements include the discovery of superheavy elements and significant advances in the nuclear physics of superheavy nuclei including experimental evidence for the “island of stability”.
“It is a pleasure to see that specific places and names (country, state, city, and scientist) related to the new elements is recognized in these four names. Although these choices may perhaps be viewed by some as slightly self-indulgent, the names are completely in accordance with IUPAC rules”, commented Jan Reedijk, who corresponded with the various laboratories and invited the discoverers to make proposals. “In fact, I see it as thrilling to recognize that international collaborations were at the core of these discoveries and that these new names also make the discoveries somewhat tangible.”
So, let’s welcome Tennessine, Muscovium, Nihonium, and Oganesson to the table of periodic elements. I imagine Don Lehrer’s Elements Song will be updated soon. In the meantime we have this from ASAP Science, which includes the new elements under their placeholder names (when the addition was first publicized in January 2016. All of the placeholder names start with U,
An April 4, 2016 news item on Science Daily focuses on carbon nanotubes that measure eight-tenths of a nanometre and transport protons more quickly than bulk water by an order of magnitude,
For the first time, Lawrence Livermore National Laboratory (LLNL) researchers have shown that carbon nanotubes as small as eight-tenths of a nanometer in diameter can transport protons faster than bulk water, by an order of magnitude.
The research validates a 200-year old mechanism of proton transport.
The transport rates in these nanotube pores, which form one-dimensional water wires, also exceed those of biological channels and man-made proton conductors, making carbon nanotubes the fastest known proton conductor. …
Practical applications include proton exchange membranes, proton-based signaling in biological systems and the emerging field of proton bioelectronics (protonics).
“The cool thing about our results is that we found that when you squeeze water into the nanotube, protons move through that water even faster than through normal (bulk) water,” said Aleksandr Noy, an LLNL biophysicist and a lead author of the paper. (Bulk water is similar to what you would find in a cup of water that is much bigger than the size of a single water molecule).
The idea that protons travel fast in solutions by hopping along chains of hydrogen-bonded water molecules dates back 200 years to the work of Theodore von Grotthuss and still remains the foundation of the scientific understanding of proton transport. In the new research, LLNL researchers used carbon nanotube pores to line up water molecules into perfect one-dimensional chains and showed that they allow proton transport rates to approach the ultimate limits for the Grotthuss transport mechanism.
“The possibility to achieve fast proton transport by changing the degree of water confinement is exciting,” Noy said. “So far, the man-made proton conductors, such as polymer Nafion, use a different principle to enhance the proton transport. We have mimicked the way biological systems enhance the proton transport, took it to the extreme, and now our system realizes the ultimate limit of proton conductivity in a nanopore.”
Of all man-made materials, the narrow hydrophobic inner pores of carbon nanotubes (CNT) hold the most promise to deliver the level of confinement and weak interactions with water molecules that facilitate the formation of one-dimensional hydrogen-bonded water chains that enhance proton transport.
Earlier molecular dynamic simulations showed that water in 0.8 nm diameter carbon nanotubes would create such water wires and predicted that these channels would exhibit proton transport rates that would be much faster than those of bulk water. Ramya Tunuguntla, an LLNL postdoctoral researcher and the first author on the paper, said that despite significant efforts in carbon nanotube transport studies, these predictions proved to be hard to validate, mainly because of the difficulties in creating sub-1-nm diameter CNT pores.
However, the Lawrence Livermore team along with colleagues from the Lawrence Berkeley National Lab and UC Berkeley was able to create a simple and versatile experimental system for studying transport in ultra-narrow CNT pores. They used carbon nanotube porins (CNTPs), a technology they developed earlier at LLNL, which uses carbon nanotubes embedded in the lipid membrane to mimic biological ion channel functionality. The key breakthrough was the creation of nanotube porins with a diameter of less than 1 nm, which allowed researchers for the first time to achieve true one-dimensional water confinement.