University of California, Riverside, scientists have moved a step closer to finding a use for the hundreds of millions of tons of plastic waste produced every year that often winds up clogging streams and rivers and polluting our oceans.
In a recent study, Kandis Leslie Abdul-Aziz, a UCR assistant professor of chemical and environmental engineering, and her colleagues detailed a method to convert plastic waste into a highly porous form of charcoal or char that has a whopping surface area of about 400 square meters per gram of mass.
Such charcoal captures carbon and could potentially be added to soil to improve soil water retention and aeration of farmlands. It could also fertilize the soil as it naturally breaks down. Abdul-Aziz, however, cautioned that more work needs to be done to substantiate the utility of such char in agriculture.
The plastic-to-char process was developed at UC Riverside’s Marlan and Rosemary Bourns College of Engineering. It involved mixing one of two common types of plastic with corn waste — the leftover stalks, leaves, husks, and cobs — collectively known as corn stover. The mix was then cooked with highly compressed hot water, a process known as hydrothermal carbonization.
The highly porous char was produced using polystyrene, the plastic used for Styrofoam packaging, and polyethylene terephthalate, or PET, the material commonly used to make water and soda bottles, among many other products.
The study followed an earlier successful effort to use corn stover alone to make activated charcoal used to filter pollutants from drinking water. In the earlier study, charcoal made from corn stover alone activated with potassium hydroxide was able to absorb 98% of the pollutant vanillin from test water samples.
In the follow-up study, Abdul-Aziz and her colleagues wanted to know if activated charcoal made from a combination of corn stover and plastic also could be an effective water treatment medium. If so, plastic waste could be repurposed to clean up water pollution. But the activated charcoal made from the mix absorbed only about 45% of vanillin in test water samples – making it ineffective for water cleanups, she said.
“We theorize that there could be still some residual plastic on the surface of the materials, which is preventing the absorption of some of these (vanillin) molecules on the surface,” she said.
Still, the ability to make highly porous charcoal by combining plastic and plant biomass waste is an important discovery, as detailed in the paper, “Synergistic and Antagonistic Effects of the Co-Pyrolysis of Plastics and Corn Stover to Produce Char and Activated Carbon,” published in the journal ACS Omega. The lead author is Mark Gale, a former UCR doctoral student who is now a lecturer at Harvey Mudd College. UCR undergraduate student Peter Nguyen is a co-author and Abdul-Aziz is the corresponding author.
“It could be a very useful biochar because it is a very high surface area material,” Abdul-Aziz said. “So, if we just stop at the char and not make it in that turn into activated carbon, I think there are a lot of useful ways that we can utilize it.”
Plastic is essentially a solid form of petroleum that accumulates in the environment, where it pollutes, entangles, and chokes and kills fish, birds, and other animals that inadvertently ingest it. Plastics also break down into micro particles that can get into our bodies and damage cells or induce inflammatory and immune reactions.
Unfortunately, it costs more to recycle used plastic than it costs to make new plastic from petroleum.
Abdul-Aziz’s laboratory takes a different approach to recycling. It is devoted to putting pernicious waste products such as plastic and plant biomass waste back into the economy by upcycling them into valuable commodities.
“I feel like we have more of an agnostic approach to plastic recycling when you can throw it in (with biomass) and use the char to better the soil,” she said. “That’s what we’re thinking.”
H/t to Lynn L. Bergeson’s and Carla N. Hutton’s October 8, 2022 posting on The National Law Review website for the news about the US National Nanotechnology Day on October 9, 2022.
Here’s more from the US National Institute of Occupational Safety and Health (NIOSH) October 6, 2022 posting by Adrienne Eastlake, Gary Roth, and Nicole Neu-Baker on the NIOSH Science blog (Note: Links and footnotes have been removed),
Every year on October 9th we celebrate National Nanotechnology Day. The date 10-9 pays homage to the nanometer scale: 10–9 (one billionth of a meter). Anything that can be measured in nanometers is extremely small! For instance, the width of a strand of human hair is about 90,000 nanometers, bacteria are between 300–5,000 nanometers, viruses are 5–300 nanometers, the diameter of deoxyribonucleic acid (DNA) is 2.5 nanometers, and a single atom is 0.1–0.5 nanometers. A healthy young adult’s fingernail grows an average of just over 1 nanometer per second (3.47 millimeters per month on average)!1 National Nanotechnology Day was created to help raise awareness of nanotechnology, to show how it is currently used in products that enrich our daily lives and to consider future challenges and opportunities.
Engineered nanomaterials (ENMs) are materials intentionally produced to have particle sizes between 1 and 100 nanometers in at least one dimension. These materials can be nanoparticles, nanotubes, or nanoplates, depending on their shape. ENMs typically have new or unique properties different from those of larger forms of the same material, making them desirable for specific product applications. These properties can contribute to increased elasticity, tensile strength, electrical conduction, and reactivity. Increasingly, they are added into existing materials to give these properties to bulk materials (such as plastics or metals). Consumer products using ENMs include cosmetics, sunscreen, food storage products, appliances, clothing, electronics, computers, sporting goods, and coatings. ENMs are also used in state-of-the-art sensors and biomedical technologies. COVID-19 research and the development of vaccines depend heavily on nanotechnology, and many vaccines use nanotechnology to improve their effectiveness. You probably are interacting with nanotechnology-enabled products every day!
Since the early 2000s, NIOSH has been at the forefront of efforts to characterize potential workplace hazards for those working with ENMs and to ensure safe and healthy workplaces, including the creation of the NIOSH Nanotechnology Research Center in 2004. Since then, NIOSH has published a quantitative risk assessment and an elemental mass-based recommended exposure limit (REL) for each of the following: carbon nanotubes/nanofibers,4 nanoscale titanium dioxide, 5 and silver nanomaterials.6 In addition, the poster Controlling Health Hazards When Working With Nanomaterials: Questions to Ask Before You Start is a helpful and easy-to-use visual resource for the workplace.
In collaboration with RTI International, NIOSH administered a survey developed by the RAND Corporation to North American companies working with nanomaterials to assess health and safety practices and the impact of efforts made by NIOSH to protect worker health and safety.9 Forty-five companies in the United States and Canada that fabricate, manufacture, handle, dispose, or otherwise use nanomaterials completed the online survey in 2019. The survey included research questions about nanomaterials in use and the overall occupational health and safety culture at the companies. Additionally, other questions asked about whether the companies interacted with NIOSH or used NIOSH resources to inform their health and safety practices and policies. More than a third (37.8%) of the 45 respondents reported using at least one NIOSH resource for information about safe handling of nanomaterials. Larger companies were more likely to report using NIOSH resources than companies employing fewer than 50 employees. While the survey was limited by the small sample size, it provided valuable insight, including that future NIOSH outreach should specifically target small businesses that use or handle nanomaterials.
We hope you find a way to celebrate National Nanotechnology Day! The National Nanotechnology Initiative (nano.gov) suggests running a 100 Billion Nanometer Dash. Sounds like quite a distance, but it is just 100 meters (328 feet) or 6.2% of a mile. As we continue to provide guidance and recommendations to keep workers safe when working with ENMs, we will be right there with you until you cross the finish line… one nanometer at a time. Good luck!
The 2022 Europlanet Prize for Public Engagement has been awarded to Dr Kosmas Gazeas and the team behind the ‘Planets In Your Hand’ tactile exhibition.
‘Planets In Your Hand’ is an interactive, mobile set of models of planetary surfaces, constructed in square frames, that gives a multisensory impression of the wide variety of surface characteristics and environmental properties of the planets in our Solar System.
The exhibition, although suitable for people of all ages, has been specifically designed for visually impaired audiences, and has travelled to schools, universities and private institutes and organisations, reaching thousands of visitors to date.
Dr Federica Duras, Chair of the Europlanet Outreach Jury, said: “Imagination and creativity has led to a stunning, original exhibition led by a passionate and committed team. Giving opportunities to ‘touch space’ with your own hands is one of the most effective ways of making science and astronomy accessible and inclusive. Congratulations to the whole team.”
The award was presented during the Europlanet Science Congress (EPSC) 2022 in Granada on behalf of the team to Dimitrios Athanasopoulos, who gave a 20-minute prize lecture. The team will also receive a cash award of 1500 Euros.
Eugenia Covernton, CEO of Lecturers Without Borders, who nominated the team for the Europlanet Prize, said: “Planets In Your Hand is an outstanding hands-on exhibition that is inclusive for people with visual impairments and is overall a great tool for the public to grasp concepts related to the different compositions of the planets”
Sophia Drakaki and Dimitris Blougouras, Founders of CityLab [CityLab_STEMLabs], a STEM center specialized in activities for children and young people, said: “The team wanted a real hands-on experience that lasts. And yes, they did it! The on-the-spot visitors can see, touch and feel the surface texture and temperature of the planets and ‘travel’ on them, with the assistance of experts in astrophysics and education that can answer the megabytes of questions that the kids generate!”
Evangelia Mavrikaki, professor of the Department of Primary Education at the National and Kapodistrian University of Athens (Greece), said: “The exhibition is portable, providing huge flexibility accessing schools and institutes in remote areas of Greece and all over the world. Science communication activities of such a kind are rare in remote places and away from large towns.”
Dr Gazeas, the team lead, who is a lecturer of observational astrophysics in the Department of Physics of the National and Kapodistrian University of Athens (Greece), said: “We are deeply honoured to receive the Europlanet Prize for Public Engagement for our efforts in science communication and public outreach activities in the frame of the project Planets In Your Hand. The selection of our project by the judges acts like a confirmation to the team for the hard work that has been done since 2017 and especially during the past 3 years.”
The 2022 EuroScience Open Forum (ESOF) runs from July 13 – 16, 2022 but the 2022 European City of Science programme runs for the entire year and a July 15, 2022 University of Leiden press release (received via email) announces a special anniversary date being celebrated by Europe’s current City of Science [Leiden, Netherlands]*,
The smallest statue in the world: Leiden physicists and sculptor build a nano-Rembrandt
Researchers from Leiden University together with sculptor Jeroen Spijker created a 3D-printed statue of Rembrandt van Rijn of 28 micrometers tall – that’s a third of the thickness of a hair. The sculpture, that isn’t visible to the naked eye, is on display at Museum De Lakenhal in Leiden. Leiden is the birth town of the famous painter, and on his birthday today, everyone can come and ‘see’ the statue for free.
To celebrate Leiden European City of Science 2022, Jeroen Spijker worked with physicists Daniela Kraft and Rachel Doherty from Leiden University on a micro-statue of Rembrandt made from polymer with a layer of platinum. At just 28 micrometres tall, the statue, which was made with a 3D printer, is around a third of the thickness of a human hair. This makes it the smallest work of art in the world, says Jeroen Spijker.
3D printed as small as possible The work is based on a bronze sculpture of Rembrandt that Spijker had previously made. This was scanned and printed as small as possible with a 3D printer. This isn’t Leiden University’s first miniature work.
In 2020 Kraft and Doherty’s research group used the same 3D printer to make the smallest boat in the world, which could even sail. At 30 micrometres, this was slightly larger than Rembrandt.
Discover the limits of scientific devices Not only are such tiny creations fun challenges but they also help scientific research. Kraft and Doherty are studying microswimmers: microscopic particles that can move in a fluid environment. They print these microswimmers themselves with a very accurate 3D printer. ‘The Rembrandt project is helping us discover the limits of our devices,’ says Doherty. ‘How small can we print something?’
On display next to Rembrandt’s paintings Visitors will see for themselves how this is invisible to the naked eye. The statue will be in the same room as paintings by Rembrandt. There is also a short film about the process. Jeroen Spijker: ‘I wanted to create a statue that I could still accept as a work of art with my own signature. Any smaller and there would have been too many distortions.’
About Leiden2022 European City of Science The nano-statue of Rembrandt was created as a project where art meets science, one aspect of Leiden2022 European City of Science. The statue will be on display at Museum De Lakenhal until 31 July.
Leiden is European City of Science in 2022: for a year Leiden is the capital of European science. Leiden University is a proud partner of Leiden2022. For an entire year Leiden2022 will be offering a programme for anyone with an open and curious mind, a programme packed with science, knowledge, art and expertise.
This piece of research on firefighters’ safety suits comes from Australia’s Nuclear Science and Technology Organisation (ANSTO). A February 3, 2022 article by Judy Skatssoon for governmentnews.com.au describes the work, (Note: Despite the date of the article, the research is from 2021)
Researchers at ANSTO are developing a new highly protective nano-material they believe will produce light-weight safety suits that are perfect for Australian firefighters.
The technology involves the use of super-thin nanosheets made from a new fire and heat-resistant non-organic compound, thermo-hydraulics specialist Professor Guan Heng Yeoh says.
The compound is created from titanium carbide and produces a lightweight coating which can be used in place of traditional fire protection measures.
A compound extracted from prawn shells, chitosan, is used to bind the nanomaterial together.
Scientists from UNSW [University of New South Wales] and ANSTO have characterised the structure of advanced materials, that could be used as a lightweight fire-retardant filler.
Fire retardant materials can self-extinguish if they ignite.
A team under Professor Guan Heng Yeoh, Director of the ARC Training Centre for Fire Retardant Materials and Safety Technologies at UNSW and Thermal-Hydraulic Specialist at ANSTO, are working to commercialise advanced products for bushfire fighting, building protection and other applications.
They investigated a family of two-dimensional transition metal carbides, carbonites and nitrides, known as MXenes.
In research published in Composites Part C, they reported the molecular structure of MXene, using neutron scattering and other advanced techniques.
Because the stability, properties, and various applications of MXene rely heavily on its atomic and molecular structure, Prof Yeoh and associates conducted a detailed structural and surface characterisation of MXene.
Knowledge from this research provided good insight on how structure affects electrical, thermoelectric, magnetic and other properties of Mxene.
Experiments at ANSTO’s Australian Centre for Neutron Scattering on the Bilby small-angle neutron scattering (SANS) instrument were undertaken to characterise the two-dimensional structure of nanosheets—revealing the thickness of the material and the gaps between layers.
Theoretical modelling was used to extrapolate key information from the SANS data regarding the structural architecture of the titanium carbide nanosheets and investigate the influence of temperature on the structure.
Measurements revealed that MXene that is suspended in a colloidal solution consists of nanosheets of ultrathin multilayers with clear sharp edges.
The material comprises nanolayers, which overlap each other and form clusters of micro-sized units that endow a level of protection.
The nanolayers can be added on top of organic fire-retardant polymers. The total thickness of MXene was found to be 3 nm.
The information was in alignment with observations made using scanning electron microscopy and transmission electron microscopy.
Senior Instrument scientist Dr Jitendra Mata said, “Using SANS is like looking through a keyhole, the keyhole gives you a size indication from 1 nanometre to 500nm. It may feel like a small size, but it’s actually not – many physical phenomena and the chemical structure occur within that size range.
“There are not many techniques in the world that gives you information about the structure and surface that accurately in a suspension and in films. Also, neutrons are ideal for many in-situ studies.”
Protective suits made with traditional retardant use as much as 30 to 40 per cent carbon compounds to achieve fire-retardant properties, which makes them heavy.
“Because we can use very low concentrations of the two-dimensional material, it comprises only about 1- 5 per cent of the total weight of the final material,” explained Prof Yeoh.
“And because it can be applied as a post-treatment, it doesn’t complicate the manufacturing process.”
When heat comes from above the surface of the material, it is conducted and moved along the nanosheets dispersing it. The nanosheets also act as a heat shield.
“At this point, it takes a lot of time to etch out the aluminium, but there are groups working on upscaling the MXene production process,” said Prof Yeoh.
“We also need to look at the performance and characteristics of the material at higher temperatures up to 800°C,” he added.
At the macro level, early tests have found the material to be an effective fire retardant.
A large team of researchers from the UNSW and ANSTO contributed to the research including first authors, Anthony Chun Yin Yuen and Timothy Bo Yuan Chen and ANSTO instrument scientist, Dr Andrew Whitten.
The versatile material could also potentially be used in energy storage devices.
This makes a nice accompaniment to my commentary (December 3, 2021 posting) on the Nature of Things programme (telecast by the Canadian Broadcasting Corporation), The Machine That Feels.
Here’s UNESCO’s (United Nations Educational, Scientific and Cultural Organization) November 25, 2021 press release making the announcement (also received via email),
UNESCO member states adopt the first ever global agreement [recommendation] on the Ethics of Artificial Intelligence
Paris, 25 Nov  – Audrey Azoulay, Director-General of UNESCO presented Thursday the first ever global standard on the ethics of artificial intelligence adopted by the member states of UNESCO at the General Conference.
This historical text defines the common values and principles which will guide the construction of the necessary legal infrastructure to ensure the healthy development of AI.
AI is pervasive, and enables many of our daily routines – booking flights, steering driverless cars, and personalising our morning news feeds. AI also supports the decision-making of governments and the private sector.
AI technologies are delivering remarkable results in highly specialized fields such as cancer screening and building inclusive environments for people with disabilities. They also help combat global problems like climate change and world hunger, and help reduce poverty by optimizing economic aid.
But the technology is also bringing new unprecedented challenges. We see increased gender and ethnic bias, significant threats to privacy, dignity and agency, dangers of mass surveillance, and increased use of unreliable AI technologies in law enforcement, to name a few. Until now, there were no universal standards to provide an answer to these issues.
In 2018, Audrey Azoulay, Director-General of UNESCO, launched an ambitious project: to give the world an ethical framework for the use of artificial intelligence. Three years later, thanks to the mobilization of hundreds of experts from around the world and intense international negotiations, the 193 UNESCO’s member states have just officially adopted this ethical framework.
“The world needs rules for artificial intelligence to benefit humanity. The Recommendation on the ethics of AI is a major answer. It sets the first global normative framework while giving States the responsibility to apply it at their level. UNESCO will support its 193 Member States in its implementation and ask them to report regularly on their progress and practices”, said Audrey Azoulay, UNESCO Director-General.
The content of the recommendation
The Recommendation [emphasis mine] aims to realize the advantages AI brings to society and reduce the risks it entails. It ensures that digital transformations promote human rights and contribute to the achievement of the Sustainable Development Goals, addressing issues around transparency, accountability and privacy, with action-oriented policy chapters on data governance, education, culture, labour, healthcare and the economy.
The Recommendation calls for action beyond what tech firms and governments are doing to guarantee individuals more protection by ensuring transparency, agency and control over their personal data. It states that individuals should all be able to access or even erase records of their personal data. It also includes actions to improve data protection and an individual’s knowledge of, and right to control, their own data. It also increases the ability of regulatory bodies around the world to enforce this.
*Banning social scoring and mass surveillance
The Recommendation explicitly bans the use of AI systems for social scoring and mass surveillance. These types of technologies are very invasive, they infringe on human rights and fundamental freedoms, and they are used in a broad way. The Recommendation stresses that when developing regulatory frameworks, Member States should consider that ultimate responsibility and accountability must always lie with humans and that AI technologies should not be given legal personality themselves.
*Helping to monitor and evalute
The Recommendation also sets the ground for tools that will assist in its implementation. Ethical Impact Assessment is intended to help countries and companies developing and deploying AI systems to assess the impact of those systems on individuals, on society and on the environment. Readiness Assessment Methodology helps Member States to assess how ready they are in terms of legal and technical infrastructure. This tool will assist in enhancing the institutional capacity of countries and recommend appropriate measures to be taken in order to ensure that ethics are implemented in practice. In addition, the Recommendation encourages Member States to consider adding the role of an independent AI Ethics Officer or some other mechanism to oversee auditing and continuous monitoring efforts.
*Protecting the environment
The Recommendation emphasises that AI actors should favour data, energy and resource-efficient AI methods that will help ensure that AI becomes a more prominent tool in the fight against climate change and on tackling environmental issues. The Recommendation asks governments to assess the direct and indirect environmental impact throughout the AI system life cycle. This includes its carbon footprint, energy consumption and the environmental impact of raw material extraction for supporting the manufacturing of AI technologies. It also aims at reducing the environmental impact of AI systems and data infrastructures. It incentivizes governments to invest in green tech, and if there are disproportionate negative impact of AI systems on the environment, the Recommendation instruct that they should not be used.
“Decisions impacting millions of people should be fair, transparent and contestable. These new technologies must help us address the major challenges in our world today, such as increased inequalities and the environmental crisis, and not deepening them.” said Gabriela Ramos, UNESCO’s Assistant Director General for Social and Human Sciences.
Emerging technologies such as AI have proven their immense capacity to deliver for good. However, its negative impacts that are exacerbating an already divided and unequal world, should be controlled. AI developments should abide by the rule of law, avoiding harm, and ensuring that when harm happens, accountability and redressal mechanisms are at hand for those affected.
If I read this properly (and it took me a little while), this is an agreement on the nature of the recommendations themselves and not an agreement to uphold them.
I’ve got two items that feature science in Black History Month 2022.
The Canadian Black Scientists Network (CBSN) is holding its first annual Black Excellence Science, Technology, Engineering, Mathematics, Medicine and Health (BE-STEMM) conference Jan. 30-Feb. 2, 2022.
The conference is featured on CBSN’s homepage and it’s where you’ll find a welcome video, which may be livestreaming an event, “Only select public sessions can be viewed here, for full access to all sessions and speakers, please register and join the conference.” Join Conference Register Now!
I did find a bit more information about the conference programme in a January 24, 2022 news item on a University of Saskatchewan (USask) Health Sciences news page (Note: Links have been removed),
The event, sponsored by the USask Office of the President and other major Canadian universities, aims to remove barriers to attracting and retaining Black Canadians in STEMM fields.
“The CBSN was created with the following vision: To elevate, make visible, celebrate and connect Black Canadians in STEMM across sectors. The CBSN is open every Canadian in the STEMM field who identifies as Black,” said University of Saskatchewan (USask) College of Medicine professor and researcher Dr. Erique Lukong (PhD), who serves as vice-president of the CBSN.
The event dates coincide with the beginning of Black History Month, which honours the legacy of Black Canadians and their communities. With the federal government announcing this year’s theme, The Future Is Now, the CBSN BE-STEMM conference provides the perfect opportunity to engage with the discoveries and innovations taking place in Black Canadian research communities.
Lukong is a leader within the CBSN and is a current USask College of Medicine breast cancer researcher who will be presenting at the BE-STEMM conference. His work focuses on analyzing the cellular, physiological and clinical roles of enzymes BRK and FRK in the development and progression of breast cancer.
The BRK enzyme is found to be elevated in 85 per cent of breast cancer tumours and has been found to cause potential drug resistance. The FRK enzyme often goes undetected in triple negative breast cancers – a type of breast cancer where the tumour is missing three important receptors commonly found in other breast cancers.
“I will discuss recent data highlighting the contrasting roles of BRK and FRK in breast cancer and show how these proteins can be targeted to improve breast cancer outcomes and especially in the most vulnerable populations like Black women where there is a disproportionate burden of triple negative breast cancer,” said Lukong.
Another exciting offering of the conference is the Leadership Summit sessions scheduled for Feb. 2 . The Leadership Summits will be comprised of six concurrent, 90-minute panels, engaging employers, academia, industries, government ministries, health-care professional and funding bodies.
USask College of Medicine assistant professor Dr. Erick McNair (PhD) is one of the facilitators of the Leadership Summit panel discussions.
Ebony magazine and Olay highlight ‘Beauty and Brains’
Ebony magazine is going to publish its first paper issue since 2019 for Black History Month February 2022.
Ebony magazine and Olay (currently a skin care brand of US company Proctor & Gamble) sponsored a beauty pageant/contest for the magazine’s cover. From the September 18, 2021 contest page on the Ebony website, Note: HBCU stands for Historically Black Colleges and Universities,
Introducing EBONY’s HBCU STEM Queens Competition
We are pleased to announce EBONY’s HBCU STEM [science, technology, engineering, mathematics] Queens competition. Since 1975, EBONY has celebrated Black collegiate women – poised to make a positive change in the African American community – through the Campus Queens competition at HBCUs (Historically Black Colleges and Universities). EBONY is proud to continue its longest-running editorial franchise. And this year, we’re excited to be partnering with Olay.
Ten beautiful, talented and accomplished HBCU STEM Queens will be featured in EBONY’s Commemorative print issue debuting on newsstands in February 2022.
Only female students who are STEM majors attending an HBCU are eligible for consideration.
The 10 selected EBONY HBCU STEM Queens with the highest number of votes will win an all-expenses-paid trip to Los Angeles to receive a makeover with professional hair and wardrobe consultation. This trip includes the official “HBCU STEM Queens” photo shoot, which will be featured in the February 2022 Commemorative issue of EBONY magazine as well as online. Students will be notified of the winning group of 10 Queens on October 8, 2021, with subsequent correspondence outlining the schedule and arrangements for the photo shoot.
Meseret Ambachew’s February 1, 2022 article for AdWeek provides more details about the partnership and the upcoming issue of the magazine.
The special issue celebrates 10 “STEM Queens” from HBCUs, selected by voters on Ebony’s website. Each of the ten winners gets a $10,000 grant, mentorship options from women scientists at P&G, and a trip to Los Angeles for the awards.
There is a huge global effort to engineer a computer capable of harnessing the power of quantum physics to carry out computations of unprecedented complexity. While formidable technological obstacles still stand in the way of creating such a quantum computer, today’s early prototypes are still capable of remarkable feats.
For example, the creation of a new phase of matter called a “time crystal.” Just as a crystal’s structure repeats in space, a time crystal repeats in time and, importantly, does so infinitely and without any further input of energy—like a clock that runs forever without any batteries. The quest to realize this phase of matter has been a longstanding challenge in theory and experiment—one that has now finally come to fruition.
In research published Nov. 30  in Nature, a team of scientists from Stanford University, Google Quantum AI, the Max Planck Institute for Physics of Complex Systems and Oxford University detail their creation of a time crystal using Google’s Sycamore quantum computing hardware.
“The big picture is that we are taking the devices that are meant to be the quantum computers of the future and thinking of them as complex quantum systems in their own right,” said Matteo Ippoliti, a postdoctoral scholar at Stanford and co-lead author of the work. “Instead of computation, we’re putting the computer to work as a new experimental platform to realize and detect new phases of matter.”
For the team, the excitement of their achievement lies not only in creating a new phase of matter but in opening up opportunities to explore new regimes in their field of condensed matter physics, which studies the novel phenomena and properties brought about by the collective interactions of many objects in a system. (Such interactions can be far richer than the properties of the individual objects.)
“Time-crystals are a striking example of a new type of non-equilibrium quantum phase of matter,” said Vedika Khemani, assistant professor of physics at Stanford and a senior author of the paper. “While much of our understanding of condensed matter physics is based on equilibrium systems, these new quantum devices are providing us a fascinating window into new non-equilibrium regimes in many-body physics.”
What a time crystal is and isn’t
The basic ingredients to make this time crystal are as follows: The physics equivalent of a fruit fly and something to give it a kick. The fruit fly of physics is the Ising model, a longstanding tool for understanding various physical phenomena – including phase transitions and magnetism – which consists of a lattice where each site is occupied by a particle that can be in two states, represented as a spin up or down.
During her graduate school years, Khemani, her doctoral advisor Shivaji Sondhi, then at Princeton University, and Achilleas Lazarides and Roderich Moessner at the Max Planck Institute for Physics of Complex Systems stumbled upon this recipe for making time crystals unintentionally. They were studying non-equilibrium many-body localized systems – systems where the particles get “stuck” in the state in which they started and can never relax to an equilibrium state. They were interested in exploring phases that might develop in such systems when they are periodically “kicked” by a laser. Not only did they manage to find stable non-equilibrium phases, they found one where the spins of the particles flipped between patterns that repeat in time forever, at a period twice that of the driving period of the laser, thus making a time crystal.
The periodic kick of the laser establishes a specific rhythm to the dynamics. Normally the “dance” of the spins should sync up with this rhythm, but in a time crystal it doesn’t. Instead, the spins flip between two states, completing a cycle only after being kicked by the laser twice. This means that the system’s “time translation symmetry” is broken. Symmetries play a fundamental role in physics, and they are often broken – explaining the origins of regular crystals, magnets and many other phenomena; however, time translation symmetry stands out because unlike other symmetries, it can’t be broken in equilibrium. The periodic kick is a loophole that makes time crystals possible.
The doubling of the oscillation period is unusual, but not unprecedented. And long-lived oscillations are also very common in the quantum dynamics of few-particle systems. What makes a time crystal unique is that it’s a system of millions of things that are showing this kind of concerted behavior without any energy coming in or leaking out.
“It’s a completely robust phase of matter, where you’re not fine-tuning parameters or states but your system is still quantum,” said Sondhi, professor of physics at Oxford and co-author of the paper. “There’s no feed of energy, there’s no drain of energy, and it keeps going forever and it involves many strongly interacting particles.”
While this may sound suspiciously close to a “perpetual motion machine,” a closer look reveals that time crystals don’t break any laws of physics. Entropy – a measure of disorder in the system – remains stationary over time, marginally satisfying the second law of thermodynamics by not decreasing.
Between the development of this plan for a time crystal and the quantum computer experiment that brought it to reality, many experiments by many different teams of researchers achieved various almost-time-crystal milestones. However, providing all the ingredients in the recipe for “many-body localization” (the phenomenon that enables an infinitely stable time crystal) had remained an outstanding challenge.
For Khemani and her collaborators, the final step to time crystal success was working with a team at Google Quantum AI. Together, this group used Google’s Sycamore quantum computing hardware to program 20 “spins” using the quantum version of a classical computer’s bits of information, known as qubits.
Revealing just how intense the interest in time crystals currently is, another time crystal was published in Science this month [November 2021]. That crystal was created using qubits within a diamond by researchers at Delft University of Technology in the Netherlands.
The researchers were able to confirm their claim of a true time crystal thanks to special capabilities of the quantum computer. Although the finite size and coherence time of the (imperfect) quantum device meant that their experiment was limited in size and duration – so that the time crystal oscillations could only be observed for a few hundred cycles rather than indefinitely – the researchers devised various protocols for assessing the stability of their creation. These included running the simulation forward and backward in time and scaling its size.
“We managed to use the versatility of the quantum computer to help us analyze its own limitations,” said Moessner, co-author of the paper and director at the Max Planck Institute for Physics of Complex Systems. “It essentially told us how to correct for its own errors, so that the fingerprint of ideal time-crystalline behavior could be ascertained from finite time observations.”
A key signature of an ideal time crystal is that it shows indefinite oscillations from all states. Verifying this robustness to choice of states was a key experimental challenge, and the researchers devised a protocol to probe over a million states of their time crystal in just a single run of the machine, requiring mere milliseconds of runtime. This is like viewing a physical crystal from many angles to verify its repetitive structure.
“A unique feature of our quantum processor is its ability to create highly complex quantum states,” said Xiao Mi, a researcher at Google and co-lead author of the paper. “These states allow the phase structures of matter to be effectively verified without needing to investigate the entire computational space – an otherwise intractable task.”
Creating a new phase of matter is unquestionably exciting on a fundamental level. In addition, the fact that these researchers were able to do so points to the increasing usefulness of quantum computers for applications other than computing. “I am optimistic that with more and better qubits, our approach can become a main method in studying non-equilibrium dynamics,” said Pedram Roushan, researcher at Google and senior author of the paper.
“We think that the most exciting use for quantum computers right now is as platforms for fundamental quantum physics,” said Ippoliti. “With the unique capabilities of these systems, there’s hope that you might discover some new phenomenon that you hadn’t predicted.”
Here’s a link to and a citation for the paper,
Time-Crystalline Eigenstate Order on a Quantum Processor by Xiao Mi, Matteo Ippoliti, Chris Quintana, Ami Greene, Zijun Chen, Jonathan Gross, Frank Arute, Kunal Arya, Juan Atalaya, Ryan Babbush, Joseph C. Bardin, Joao Basso, Andreas Bengtsson, Alexander Bilmes, Alexandre Bourassa, Leon Brill, Michael Broughton, Bob B. Buckley, David A. Buell, Brian Burkett, Nicholas Bushnell, Benjamin Chiaro, Roberto Collins, William Courtney, Dripto Debroy, Sean Demura, Alan R. Derk, Andrew Dunsworth, Daniel Eppens, Catherine Erickson, Edward Farhi, Austin G. Fowler, Brooks Foxen, Craig Gidney, Marissa Giustina, Matthew P. Harrigan, Sean D. Harrington, Jeremy Hilton, Alan Ho, Sabrina Hong, Trent Huang, Ashley Huff, William J. Huggins, L. B. Ioffe, Sergei V. Isakov, Justin Iveland, Evan Jeffrey, Zhang Jiang, Cody Jones, Dvir Kafri, Tanuj Khattar, Seon Kim, Alexei Kitaev, Paul V. Klimov, Alexander N. Korotkov, Fedor Kostritsa, David Landhuis, Pavel Laptev, Joonho Lee, Kenny Lee, Aditya Locharla, Erik Lucero, Orion Martin, Jarrod R. McClean, Trevor McCourt, Matt McEwen, Kevin C. Miao, Masoud Mohseni, Shirin Montazeri, Wojciech Mruczkiewicz, Ofer Naaman, Matthew Neeley, Charles Neill, Michael Newman, Murphy Yuezhen Niu, Thomas E. O’Brien, Alex Opremcak, Eric Ostby, Balint Pato, Andre Petukhov, Nicholas C. Rubin, Daniel Sank, Kevin J. Satzinger, Vladimir Shvarts, Yuan Su, Doug Strain, Marco Szalay, Matthew D. Trevithick, Benjamin Villalonga, Theodore White, Z. Jamie Yao, Ping Yeh, Juhwan Yoo, Adam Zalcman, Hartmut Neven, Sergio Boixo, Vadim Smelyanskiy, Anthony Megrant, Julian Kelly, Yu Chen, S. L. Sondhi, Roderich Moessner, Kostyantyn Kechedzhi, Vedika Khemani & Pedram Roushan. Nature (2021) DOI: https://doi.org/10.1038/s41586-021-04257-w Published 30 November 2021
This is a preview of the unedited paper being provided by Nature. Click on the Download PDF button (to the right of the title) to get access.
Globally, the Earth system has thousands of terragrams (Tg) (1 Tg = 1012g) of mineral nanoparticles moving around the planet each year. These mineral nanoparticles are ubiquitously distributed throughout the atmosphere, oceans, waters, soils, in and/or on most living organisms, and even within proteins such as ferritin. In natural environments, mineral nanozymes can be produced by two pathways: ‘top down’ and ‘bottom up’ processes. Specifically, the weathering or human-promoted breakdown of bulk materials can result in nanomaterials directly (a top-down process), or nanomaterials can grow from precursors through crystallization, reaction, or biological roles (a bottom-up process).
These mineral nanoparticles can possess multiple enzyme-like properties, e.g., oxidase, peroxidase, catalase, and superoxide dismutase, depending on the local environment. Iron-containing minerals, e.g., ferrihydrite, hematite, and magnetite, are ubiquitous in Earth systems and possess peroxidase-like activity. Among these iron (oxyhydr)oxides, ferrihydrite exhibited the highest peroxidase-like activity, owing to its smallest particle size and largest specific surface area. Because of the presence of ferrous iron, magnetite has considerably high peroxidase-like activity.
Compared with natural enzymes, mineral nanozymes show several advantages, such as low cost, increased stability, sustainable catalytic activity, and robustness to harsh environments. Because of their larger specific surface area, high ratios of surface atoms, wide band gap, and strong catalytic activities, mineral nanozymes play essential roles in biogeochemical cycles of elements in ecosystems.
Fungi and bacteria contribute approximately 70 Gt carbon (C) (1 Gt = 10 9 t) and 120 Gt C to global biomass, respectively. Given that fungal hyphae can cumulatively extend hundreds of kilometers in soils kg-1 in environments such as the rhizosphere (i.e., 200-800 km kg-1) and that more than 94% of land plants and fungi form a symbiotic relationship, mineral nanozymes may have important implications in microbial-mineral coevolution, nutrient cycling in the surface Earth system, mineral carbon sequestration, and alleviation of global climate changes.
In Earth systems, taxonomically and functionally diverse microorganisms are a vast source of superoxide (O2* -) or hydrogen peroxides (H2O2). These mineral nanozymes can regulate the levels of reactive oxygen species (ROS), including H2O2, O2* – and hydroxyl radicals (HO* ). By producing a strong oxidative HO* , the interaction between mineral nanozymes and microorganisms may play an important role in driving the biogeochemical cycle of elements (Figure 2).
“All of the investigations on mineral nanozymes are still in the laboratory stage and are not field studies,” said Guang-Hui Yu, a scientist at the School of Earth System Science, Tianjin University, in the Chinese city of Tianjin.
“The catalytic activity of mineral nanozymes is mainly determined by the oxygen vacancies (OVs) on the mineral surface”, the researchers wrote in an article titled “Fungal Nanophase Particles Catalyze Iron Transformation for Oxidative Stress Removal and Iron Acquisition.”
“These oxygen vacancies are often occupied by hydroxyl groups on the mineral surface,” they explained.
Since mineral nanozymes can catalyze H2O2 to produce highly oxidizing HO* , they have been extensively used in the field of environmental remediation. Compared with natural enzymes, mineral nanozymes can degrade organic pollutants in a wider pH range. For example, by degrading H2O2, Fe3O4 nanoparticles could effectively remove rhodamine B (RhB) in the pH range from 3.0 to 9.0.
“The effects of mineral nanozymes on microbial communities in the environment remain unclear,” wrote the two researchers, “the findings of mineral nanozymes may have revealed a previously unknown feedback route of microbe-mineral coevolution that could shed light on a number of long-standing questions, such as the origin and evolution of life by modulating ROS levels.”
These two scholars likewise revealed in the study, which was published in the Science China Earth Sciences, that the discovery of nanomaterials as new enzyme mimetics has changed the traditional idea that nanomaterials are chemically inert in Earth systems. Given the terragram (Tg)-level abundance of mineral nanoparticles in Earth systems, it is statistically highly probable for some of them, particularly those of biotic origin, to behave as mineral nanozymes to catalyze superoxide and H2O2 and promote the biogeochemical cycles of oxygen and other elements.
Belated congratulations to the researchers at the Delft University of Technology! Very exciting news as an April 15, 2021 news item on ScienceDaily makes clear,
A team of researchers from QuTech in the Netherlands reports realization of the first multi-node quantum network, connecting three quantum processors. In addition, they achieved a proof-of-principle demonstration of key quantum network protocols. Their findings mark an important milestone towards the future quantum internet and have now been published in Science.
An April 15, 2021 Delft University of Technology (TU Delft) press release (also on EurekAlert), which originated the news item, describes the breakthrough in more detail, Note: QuTech is the research center for Quantum Computing and Quantum Internet, a collaboration between TU Delft and TNO is Nederlandse Organisatie voor Toegepast Natuurwetenschappelijk Onderzoek (English: Netherlands Organisation for Applied Scientific Research), an independent research organization),
The quantum internet
The power of the Internet is that it allows any two computers on Earth to be connected with each other, enabling applications undreamt of at the time of its creation decades ago. Today, researchers in many labs around the world are working towards first versions of a quantum internet – a network that can connect any two quantum devices, such as quantum computers or sensors, over large distances. Whereas today’s Internet distributes information in bits (that can be either 0 or 1), a future quantum internet will make use of quantum bits that can be 0 and 1 at the same time. ‘A quantum internet will open up a range of novel applications, from unhackable communication and cloud computing with complete user privacy to high-precision time-keeping,’ says Matteo Pompili, PhD student and a member of the research team. ‘And like with the Internet 40 years ago, there are probably many applications we cannot foresee right now.’
Towards ubiquitous connectivity
The first steps towards a quantum internet were taken in the past decade by linking two quantum devices that shared a direct physical link. However, being able to pass on quantum information through intermediate nodes (analogous to routers in the classical internet) is essential for creating a scalable quantum network. In addition, many promising quantum internet applications rely on entangled quantum bits, to be distributed between multiple nodes. Entanglement is a phenomenon observed at the quantum scale, fundamentally connecting particles at small and even at large distances. It provides quantum computers their enormous computational power and it is the fundamental resource for sharing quantum information over the future quantum internet. By realizing their quantum network in the lab, a team of researchers at QuTech – a collaboration between Delft University of Technology and TNO – is the first to have connected two quantum processors through an intermediate node and to have established shared entanglement between multiple stand-alone quantum processors.
Operating the quantum network
The rudimentary quantum network consists of three quantum nodes, at some distance within the same building. To make these nodes operate as a true network, the researchers had to invent a novel architecture that enables scaling beyond a single link. The middle node (called Bob) has a physical connection to both outer nodes (called Alice and Charlie), allowing entanglement links with each of these nodes to be established. Bob is equipped with an additional quantum bit that can be used as memory, allowing a previously generated quantum link to be stored while a new link is being established. After establishing the quantum links Alice-Bob and Bob-Charlie, a set of quantum operations at Bob converts these links into a quantum link Alice-Charlie. Alternatively, by performing a different set of quantum operations at Bob, entanglement between all three nodes is established.
Ready for subsequent use
An important feature of the network is that it announces the successful completion of these (intrinsically probabilistic) protocols with a “flag” signal. Such heralding is crucial for scalability, as in a future quantum internet many of such protocols will need to be concatenated. ‘Once established, we were able to preserve the resulting entangled states, protecting them from noise,’ says Sophie Hermans, another member of the team. ‘It means that, in principle, we can use these states for quantum key distribution, a quantum computation or any other subsequent quantum protocol.’
Quantum Internet Demonstrator
This first entanglement-based quantum network provides the researchers with a unique testbed for developing and testing quantum internet hardware, software and protocols. ‘The future quantum internet will consist of countless quantum devices and intermediate nodes,’ says Ronald Hanson, who led the research team. ‘Colleagues at QuTech are already looking into future compatibility with existing data infrastructures.’ In due time, the current proof-of-principle approach will be tested outside the lab on existing telecom fibre – on QuTech’s Quantum Internet Demonstrator, of which the first metropolitan link is scheduled to be completed in 2022.
In the lab, the researchers will focus on adding more quantum bits to their three-node network and on adding higher level software and hardware layers. Pompili: ‘Once all the high-level control and interface layers for running the network have been developed, anybody will be able to write and run a network application without needing to understand how lasers and cryostats work. That is the end goal.’