From seawater to drinking water – With just a push of a button!

MIT Researchers build a portable desalination unit that generates clear, clean drinking water without the need for filters or high-pressure pumps.

MIT researchers have developed a portable desalination unit, weighing less than 10 kilograms, that can remove particles and salts to generate drinking water.

The suitcase-sized device, which requires less power to operate than a cell phone charger, can also be driven by a small, portable solar panel, which can be purchased online for around $50. It automatically generates drinking water that exceeds World Health Organization quality standards. The technology is packaged into a user-friendly device that runs with the push of one button.

Unlike other portable desalination units that require water to pass through filters, this device utilizes electrical power to remove particles from drinking water. Eliminating the need for replacement filters greatly reduces the long-term maintenance requirements.

This could enable the unit to be deployed in remote and severely resource-limited areas, such as communities on small islands or aboard seafaring cargo ships. It could also be used to aid refugees fleeing natural disasters or by soldiers carrying out long-term military operations.

“This is really the culmination of a 10-year journey that I and my group have been on. We worked for years on the physics behind individual desalination processes, but pushing all those advances into a box, building a system, and demonstrating it in the ocean, that was a really meaningful and rewarding experience for me,” says senior author Jongyoon Han, a professor of electrical engineering and computer science and of biological engineering, and a member of the Research Laboratory of Electronics (RLE).

Joining Han on the paper are first author Junghyo Yoon, a research scientist in RLE; Hyukjin J. Kwon, a former postdoc; SungKu Kang, a postdoc at Northeastern University; and Eric Brack of the U.S. Army Combat Capabilities Development Command (DEVCOM). The research has been published online in Environmental Science and Technology.

Watch: YouTube Videp

Filter-free technology

Commercially available portable desalination units typically require high-pressure pumps to push water through filters, which are very difficult to miniaturize without compromising the energy-efficiency of the device, explains Yoon.

Instead, their unit relies on a technique called ion concentration polarization (ICP), which was pioneered by Han’s group more than 10 years ago. Rather than filtering water, the ICP process applies an electrical field to membranes placed above and below a channel of water. The membranes repel positively or negatively charged particles — including salt molecules, bacteria, and viruses — as they flow past. The charged particles are funneled into a second stream of water that is eventually discharged.

The process removes both dissolved and suspended solids, allowing clean water to pass through the channel. Since it only requires a low-pressure pump, ICP uses less energy than other techniques.

But ICP does not always remove all the salts floating in the middle of the channel. So the researchers incorporated a second process, known as electrodialysis, to remove remaining salt ions.

Yoon and Kang used machine learning to find the ideal combination of ICP and electrodialysis modules. The optimal setup includes a two-stage ICP process, with water flowing through six modules in the first stage then through three in the second stage, followed by a single electrodialysis process. This minimized energy usage while ensuring the process remains self-cleaning.

“While it is true that some charged particles could be captured on the ion exchange membrane, if they get trapped, we just reverse the polarity of the electric field and the charged particles can be easily removed,” Yoon explains.

They shrunk and stacked the ICP and electrodialysis modules to improve their energy efficiency and enable them to fit inside a portable device. The researchers designed the device for nonexperts, with just one button to launch the automatic desalination and purification process. Once the salinity level and the number of particles decrease to specific thresholds, the device notifies the user that the water is drinkable.

The researchers also created a smartphone app that can control the unit wirelessly and report real-time data on power consumption and water salinity.

Beach tests

After running lab experiments using water with different salinity and turbidity (cloudiness) levels, they field-tested the device at Boston’s Carson Beach.

Yoon and Kwon set the box near the shore and tossed the feed tube into the water. In about half an hour, the device had filled a plastic drinking cup with clear, drinkable water.

“It was successful even in its first run, which was quite exciting and surprising. But I think the main reason we were successful is the accumulation of all these little advances that we made along the way,” Han says.

The resulting water exceeded World Health Organization quality guidelines, and the unit reduced the amount of suspended solids by at least a factor of 10. Their prototype generates drinking water at a rate of 0.3 liters per hour, and requires only 20 watts of power per liter.

“Right now, we are pushing our research to scale up that production rate,” Yoon says.

One of the biggest challenges of designing the portable system was engineering an intuitive device that could be used by anyone, Han says.

Yoon hopes to make the device more user-friendly and improve its energy efficiency and production rate through a startup he plans to launch to commercialize the technology.

In the lab, Han wants to apply the lessons he’s learned over the past decade to water-quality issues that go beyond desalination, such as rapidly detecting contaminants in drinking water.

“This is definitely an exciting project, and I am proud of the progress we have made so far, but there is still a lot of work to do,” he says.

For example, while “development of portable systems using electro-membrane processes is an original and exciting direction in off-grid, small-scale desalination,” the effects of fouling, especially if the water has high turbidity, could significantly increase maintenance requirements and energy costs, notes Nidal Hilal, professor of engineering and director of the New York University Abu Dhabi Water research center, who was not involved with this research.

“Another limitation is the use of expensive materials,” he adds. “It would be interesting to see similar systems with low-cost materials in place.”

The research was funded, in part, by the DEVCOM Soldier Center, the Abdul Latif Jameel Water and Food Systems Lab (J-WAFS), the Experimental AI Postdoc Fellowship Program of Northeastern University, and the Roux AI Institute.

Battery Science 101

What is a battery?

ARGONNE NATIONAL LABORATORY

Batteries power our lives by transforming energy from one type to another.

Whether a traditional disposable battery (e.g. AA) or a rechargeable lithium-ion battery (used in cell phones, laptops and cars), a battery stores chemical energy and releases electrical energy.

There are four key parts in a battery — the cathode (positive side of the battery), the anode (negative side of the battery), a separator that prevents contact between the cathode and anode and a chemical solution known as an electrolyte that allows the flow of electrical charge between the cathode and anode.

Lithium-ion batteries that power cell phones, for example, typically consist of a cathode made of cobalt, manganese, and nickel oxides and an anode made out of graphite, the same material found in many pencils. The cathode and anode store the lithium.

When a lithium-ion battery is turned on, positively charged particles of lithium (ions) move through the electrolyte from the anode to cathode. Chemical reactions occur that generate electrons and convert stored chemical energy in the battery to electrical current.

When you plug in your cell phone to charge the lithium-ion battery, the chemical reactions go in reverse: the lithium ions move back from the cathode to the anode.

As long as lithium ions shuttle back and forth between the anode and cathode, there is a constant flow of electrons. This provides the energy to keep your devices running. Since this cycle can be repeated hundreds of times, this type of battery is rechargeable.

Read more »

HOW DOES A LITHIUM-ION BATTERY WORK?

Lithium-based batteries power our daily lives, from consumer electronics to national defense

DOWNLOAD PDF

A lithium-ion battery is a type of rechargeable battery. It has four key parts:

• 1The cathode (the positive side), typically a combination of nickel, manganese and cobalt oxides.
• 2The anode (the negative side), commonly made out of graphite, the same material found in many pencils.
• 3A separator that prevents contact between the anode and cathode.
• 4A chemical solution known as an electrolyte that moves lithium ions between the cathode and anode. The anode and cathode store lithium.

When the battery is in use, positively charged particles of lithium (ions) move through the electrolyte from the anode to cathode. Chemical reactions occur that generate electrons and convert stored chemical energy in the battery to electrical current.

When the battery is charging, the chemical reactions go
in reverse: the lithium ions move back from the cathode to the anode.

Batteries and the U.S. Department of Energy’s (DOE) Argonne National Laboratory

Argonne is recognized as a global leader in battery science and technology. Over the past sixty years, the lab’s pivotal discoveries have strengthened the U.S. battery manufacturing industry, aided the transition of the U.S. automotive fleet toward plug-in hybrid and electric vehicles, and enabled greater use of renewable energy, such as wind and solar power.

The lab’s research spans every aspect of battery development, from the breakthrough fundamental science of the Argonne-led Joint Center for Energy Storage Research, a DOE Energy Innovation Hub, to the Argonne Collaborative Center for Energy Storage Science, a cross-lab collective of scientists and engineers that solves complex battery problems through multidisciplinary research.

Argonne researchers are also exploring how to accelerate the recycling of lithium-ion batteries through the DOE’s ReCell Center, a collaboration led by Argonne that includes the National Renewable Energy Laboratory, Oak Ridge National Laboratory, as well as Worcester Polytechnic Institute, University of California at San Diego and Michigan Technological University.

For another take on “Batteries 101,” check out DOE Explains.

Building Artificial Neurons with Mathematics

Credit: Pixabay/CC0 Public Domain by Ecole Polytechnique Federale de Lausanne

EPFL’s Blue Brain Project has found a way to use only mathematics to automatically draw neurons in 3D, meaning we are getting closer to being able to build digital twins of brains.

Santiago Ramón y Cajal, a Spanish physician from the turn of the 19th century, is considered by most to be the father of modern neuroscience. He stared down a microscope day and night for years, fascinated by chemically stained neurons he found in slices of human brain tissue.

By hand, he painstakingly drew virtually every new type of neuron he came across using nothing more than pen and paper. As the Charles Darwin for the brain, he mapped every detail of the forest of neurons that make up the brain, calling them the “butterflies of the brain.”

Today, 200 years later, Blue Brain has found a way to dispense with the human eye, pen and paper, and use only mathematics to automatically draw neurons in 3D as digital twins. Math can now be used to capture all the “butterflies of the brain,” which allows us to use computers to build any and all the billons of neurons that make up the brain. And that means we are getting closer to being able to build digital twins of brains.

These billions of neurons form trillions of synapses—where neurons communicate with each other. Such complexity needs comprehensive neuron models and accurately reconstructed detailed brain networks in order to replicate the healthy and disease states of the brain. Efforts to build such models and networks have historically been hampered by the lack of experimental data available.

But now, scientists at the EPFL Blue Brain Project using algebraic topology, a field of Math, have created an algorithm that requires only a few examples to generate large numbers of unique cells. Using this algorithm—the Topological Neuronal Synthesis (TNS), they can efficiently synthesize millions of unique neuronal morphologies.

The TNS algorithm is of huge importance for the rapidly growing field of computational neuroscience, which increasingly relies on biologically-realistic models from the single cell level to large-scale neuronal networks. Accurate neuronal morphologies, in particular, lie at the heart of these efforts as they are essential for defining cell types, discerning their functional roles, investigating structural alterations associated with diseased brain states and, identifying what conditions make brain networks sufficiently robust to support the complex cortical processes that are fundamental for a healthy brain.

Therefore, it is essential to accurately reconstruct detailed brain networks in order to replicate the healthy and disease states of the brain.

In a paper published in Cell Reports, a team led by Lida Kanari has applied the Topological Morphology Descriptor (TMD) introduced in Kanari et al. 2018, which reliably categorizes dendritic morphologies, to digitally synthesize dendritic morphologies from all layers and morphological types of the rodent cortex. The advantages of this topology-driven approach are multiple, as the new TNS algorithm, is generalizable to new types of cells, needs little input data and does not require fine tuning because it captures feature correlations.

Enabling the rapid digital reconstruction of entire brain regions from relatively few reference cells

The TNS algorithm driven by the topological architecture of dendrites generates realistic morphologies for a large number of distinct cortical neuronal cell types with realistic morphological and electrical properties. This has enabled the rapid digital reconstruction of entire brain regions from relatively few reference cells, thereby allowing the investigation of links between neuronal morphologies and brain function across different spatio-temporal scales and addressing the challenge of insufficient biological reconstructions.

A multi-stage validation documented in the paper ensures that the synthesized cells reproduce the shapes of reconstructed neurons with respect to three modalities: 1. Their morphological characteristics, 2. The electrical activity of single cells and, 3. The connectivity of the network they form.

Lida Kanari explains that “the findings are already enabling Blue Brain to build biologically detailed reconstructions and simulations of the mouse brain, by computationally reconstructing brain regions for simulations which replicate the anatomical properties of neuronal morphologies and include region specific anatomy. We address one of the fundamental problems for neuroscience—the scarcity of experimental neuronal reconstructions since the topological synthesis requires only a few examples to generate large numbers of unique cells. Using the TNS algorithm, we can efficiently synthesize millions of unique neuronal morphologies (10 million cells in a few hours),” she concludes.

Facilitating medical applications

“Comprehensive neuron models are essential for defining cell types, discerning their functional roles and investigating structural alterations associated with diseased brain states,” affirms Blue Brain Founder and Director, Prof. Henry Markram. “The researchers synthesized cortical networks based on structural alterations of dendrites associated with medical conditions and revealed principles linking branching properties to the structure of large-scale networks.”

“As the TNS algorithm is implemented in an open source software, this will allow the modeling of brain diseases in terms of single cells and networks, as it provides a tool to directly investigate the link between local morphological properties and the connectivity of the neuronal network they form. This approach is of particular interest for medical applications as it enables the investigation of diseases in terms of the emergence of global network pathology from local structural changes in neuron morphologies,” he concludes.

+ Explore further

More information: Lida Kanari et al, Computational synthesis of cortical dendritic morphologies, Cell Reports (2022). DOI: 10.1016/j.celrep.2022.110586

Topological Neuron Synthesis Algorithm: portal.bluebrain.epfl.ch/resou … al-neuron-synthesis/

Innovations in Dentistry: Navigational Surgery, Robotics, and Nanotechnology

** Note to Readers: With more than a few ‘dental people connections’ in the family, please indulge us this ‘nano-departure’ from our normal Posts on Renewable Energy (Green Hydrogen, Nano-Enhanced Battery Materials & Storage), Nano-Bio Medicine (Nano-Enhanced Cancer Research & Treatment) and Water Treatment (Nano-Enhanced Membranes and Nanoparticles). We hope you can “sink your teeth” into these amazing advances in Technology making our lives a little better. – Team GNT

A Dental Story

Reggie falls and loses two of his teeth. He soon finds it difficult to chew correctly and realizes he might visit the dentist for implants. Coincidentally, his grandmother had to get implants years ago. He remembers how they had to take multiple visits to the dentist and how long it took to fix her smile. Ultimately, Reggie gets discouraged and postpones his visit to the dentist.

This story typically depicts one of the drawbacks of traditional dental procedures, which has been corrected by technological advancements in dentistry over the years. Most dental experts today, like the dentist Steven Shapiro, DMD attests to the benefits of advanced technology such as nanotechnology and robotics in dental surgeries and procedures.

It has also been established that, because of these innovations, there is higher accuracy in surgeries, reducing the risk of complications which is a big win for the dental industry today. This is not to mention the increased convenience for the patient. So, Reggie might not have to wait that long to get his dental implants anymore.

Here are some of the technology innovations that have rocked the world of dentistry over the years.

Navigational dentistry

Navigation surgery in dental procedures is associated with better accuracy, improved reliability, and convenience. These techniques are often linked with imaging systems like cone-beam computed tomography. This ensures better safety as compared with conventional dental procedures. There’s also a generally reduced failure rate, especially for dental implants, since less invasive methods are used. Therefore, there’s an increased success rate of such surgeries and fewer major complications.

Robotics-assisted dental surgeries

Advanced artificial intelligence in robotics is now used in navigational surgery for many dental procedures such as implant treatment periodontics, orthodontics, endodontics, and so much more. Increased precision and better dental care are made available using robotics over traditional freehand techniques. Dental clinicians can also use artificial intelligence to create new methods of diagnosing and treatment.

Complications of traditional implant surgery vs use of robotics

Several things could go wrong during implant surgery. These include:

• Injuries are caused by incision or perforation of the lingual plate, inferior border, inferior alveolar canal, and so on;
• Tissue necrosis or death;
• Implant Dehiscence defect; and
• Damage to a nerve.

The above kinds of injury can cause complications and severe infections. Other factors can lead to complications such as lack of adequate dental expertise, patient-related or underlying conditions, and implant location.

A surgical guide should help the dentist navigate during traditional dental surgeries, but there could be specific errors, such as fitting and angulation. With robotics, the clinician can change direction during the implant procedure, unlike surgical guides, which don’t allow any adjustments. Other benefits of using robotics in surgical implant treatment are:

• Imaging during the preoperative phase to enable the dentist properly views the anatomical features.
• It hands over control to the dentist after its job is done.
• It makes use of sensory feedback for correct angulation and positioning.
• It provides navigational guidance to the dental clinician.
• It is more convenient for the patient.

Use of microrobots

Microrobots can be used in endodontic therapy. In this procedure, the microrobot is placed on the tooth. It carries out the root canal procedure, including cleaning and drilling, to reduce errors and improve the reliability of the process.

Nanotechnology

Nanotechnology is simply the branch of engineering and technology concerned with building and designing nanobots. These nanobots are tiny machines that can interact with specific cells in the body. This interaction can lead to changes in treatment delivery and overall therapeutic effect.

Nano dentistry is the application of nanotechnology in the field of dentistry. Due to its small size(nanometers), it is used at the cellular or molecular level to manage all complicated cases and reduce the failure rate of dental procedures. Nanotech is used in restorative surgeries, periodontics, bone replacement, and drug delivery.

More beneficial than conventional methods

In summary, artificial intelligence and nanotechnology are more beneficial than conventional methods but are slowly used in dentistry compared to other areas of medicine. Dentists must play a massive role in adopting these techniques and increasing their knowledge about these technological advancements.

Since the goal of patient care is optimum treatment, tech advancements have been proven to provide a better quality of treatment and are worth giving a shot. Conventional dental procedures are time-consuming and are also largely inconvenient.

Still, technology can take all these disadvantages away by saving time, improving precision and accuracy, improving reliability, reduce complications and failure rates for dental procedures.

Studying Nanoparticle Impact on Crops Informs Safe Agriculture – Nanomaterials to Enhance Crop Yield – Blessing or Curse?

Study: Nanoparticle-based toxicity in perishable vegetable crops: Molecular insights, impact on human health and mitigation strategies for sustainable cultivation. Image Credit: funnyangel/Shutterstock.com

Nanomaterials to Enhance Crop Yield – Blessing or Curse?

Nanotechnology is agriculture’s most advanced transdisciplinary tool, with great potential to impact the growth and development of plants.

The employment of nanoparticles (NPs) as well as nanomaterials (NMs) in agriculture, notably the production of perishable vegetable crops, has expanded dramatically as a result of advances in nanotechnology. Plant development and growth, postharvest handling of fruits and vegetables, plant stress management and seed germination are all influenced by NPs and NMs.

Several aspects of vegetable agriculture have benefited through the application of NPs, including the growth and development of plants, biotic and abiotic stress control, as well as postharvest handling of vegetable crops.

Nevertheless, the hazardous impact of nanoparticles on plants has also been studied, with several studies concluding that greater NP concentrations have a detrimental impact on plants, including genotoxic, chemical, physiological as well as morphological alterations. Excessive reactive oxygen and oxidative stress species formation caused by these NPs can induce toxicity in plants, affecting cellular macromolecules and resulting in unbalanced metabolic and biological processes.

The Importance of Understanding NP Toxicity

Related Stories

• A Green Method for Silver Nanoparticle Synthesis Using H. isora
• Using Nanoparticle Tracking Analysis (NTA) to Assess Nanoparticle Toxicity in Waste Water
• Magneto-Thermal Heating Effects in Magnetic Nanoparticles

As a result of nanoparticle-induced toxicity, the knowledge of the mechanisms underpinning NP-plant interactions is essential for understanding plant biochemical and physiological responses, assessing phytotoxicity, and designing mitigation methods for vegetable crop management. The study conducted by the researchers discusses current biochemical, physical, and molecular findings on nanotoxicity in vegetable crops to address this.

Mechanism of Toxicity Propagation

Once crops are exposed to nanoparticles, free radicals and cellular redox state alterations like hydrogen peroxide (H₂O₂), superoxide anion (O₂^–), hydroxyl (OH), and oxygen singlet are produced, disrupting cell stability as well as functions by negatively impacting biomolecules like membrane lipids, DNA, protein, and carbohydrates.

Aggregation size, concentration, surface modification and shape are all factors that influence the amount of NP-based phytotoxicity. NPs have been shown to cause plant organ specificity, stress reliance and species-specific toxicity in the form of germination and seedling development. Studying the biochemical and physiological reactions exerted by plants, along with assessing phytotoxicity in vegetable crops, necessitates elucidating the mechanism of interactions with NPs.

Influences Differ by the Types of Nanoparticles

NMs are categorized in a variety of ways, but the most common ones are determined by the chemical composition as well as the number of dimensions of the composite. These materials can be classified as zero-dimensional, one-dimensional, two-dimensional or three-dimensional (one dimension on the nanoscale level). NPs are classified as organic, inorganic, or carbon-based based on their chemical structure.

Both the type of nanoparticle and plant species contribute to phototoxicity and are thus key factors to consider. Cucumber root development was shown to have slowed by the retention of aluminum oxide nanoparticles, whereas radish root growth was enhanced.

Titanium oxide nanoparticles were shown to limit cucumber root development while promoting the growth of spinach. In lettuce, the carbon nanotube suspension lowered seedling length, germination rate, as well as biomass; nevertheless, the same parameters were determined to be raised in tomatoes and onions.

Different NPs had different impacts on root development, which varied according to the plant species, with lettuce being the most vulnerable to phytotoxicity. The toxicity of plants has also been shown to be affected by surface alteration spurred by nanomaterials.

Remedies and Future of Nano Agriculture

While significant progress has been achieved in nanotechnology and agriculture, especially when nanoparticles are now widely employed in a variety of commercial settings, the use of nanoparticles in agricultural businesses lacks a well-defined assessment framework and risk governance across domains.

As a result, advancements in this subject are required not just for sustainable agriculture, as well as for regulation, risk evaluation, and management, as well as risk assessment and analysis. Agriculture and health sectors might benefit from omics technology, technological advancements, and multidisciplinary methods for environmental expansion and legislative implementation.

Reference

Sharma, S., Shree, B., Aditika, Sharma, A., Irfan, M., and Kumar, P. (2022). Nanoparticle-based toxicity in perishable vegetable crops: Molecular insights, impact on human health and mitigation strategies for sustainable cultivation. Environmental Research. Available at: https://www.sciencedirect.com/science/article/pii/S0013935122004959?via%3Dihub