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Water Filtration Is Being Revolutionized by What Scientists Found
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Posted by Okachinepa on 12/12/2024 @


Courtesy of SynEvol
Credit: Jennifer Chu
From microscopic crustaceans, corals, and krill to larger creatures like mollusks, barnacles, basking sharks, and baleen whales, filter feeders may be found all over the animal kingdom. The mobula ray, one of these filter feeders, has developed a special feeding technique that may lead to improved industrial water filter designs, according to MIT experts.
Researchers have described the filter-feeding system of the mobula ray, a group of aquatic rays that comprises seven devil ray species and two manta ray species, in a publication published in the Proceedings of the National Academy of Sciences. As water enters their mouths and exits through their gills, mobula rays catch plankton by swimming through plankton-rich waters with their mouths wide open.
Water is directed toward the ray's gills by means of parallel, comb-like structures called plates that run the length of its mouth. These carefully placed plates, according to the MIT team, force plankton particles to bounce deeper into the ray's mouth rather than escape via its gills. Furthermore, the gills draw oxygen from the water that is expelled, enabling the ray to simultaneously breathe and feed.
According to study author Anette "Peko" Hosoi, a Pappalardo Professor of Mechanical Engineering at MIT, "we demonstrate that the mobula ray has evolved the geometry of these plates to be the ideal size to balance feeding and breathing."

Courtesy of SynEvol
Credit: Jennifer Chu
Inspired by the mobula ray's plankton-filtering capabilities, the engineers created a basic water filter. They examined the water flow through the filter after it was equipped with features that resembled 3D-printed plates. The scientists used the findings of these trials to create a blueprint that they claim designers may utilize to maximize industrial cross-flow filters, which share many of the mobula ray's configurations.
Lead author and MIT postdoc Xinyu Mao PhD '24 states, "We want to expand the design space of traditional cross-flow filtration with new knowledge from the manta ray." "People may be able to enhance overall filter performance by selecting a parameter regime of the mobula ray."

Courtesy of SynEvol
Credit: Jennifer Chu
The group's concentration on filtration during the height of the Covid pandemic, when they were creating face masks to filter out the virus, gave rise to the latest study. Since then, Mao has turned his attention to researching animal filtration and how specific filter-feeding mechanisms could enhance industrial filters, including those found in water treatment facilities.
Permeability, or how easily a fluid can pass through a filter, and selectivity, or how well a filter blocks out particles of a particular size, must be balanced in any industrial filter, according to Mao. A membrane studded with big holes, for example, may be very permeable, allowing a lot of water to pass through with relatively little energy. However, the membrane would have very little selectivity because of its enormous holes, which would allow many particles to pass through. Similarly, a membrane with a lot fewer pores would be more discriminating, but it would also need more energy to force the water through the tiny holes.
"How can we improve upon this trade-off between permeability and selectivity?" we questioned ourselves. Hosoi says.
Mao discovered that the mobula ray had achieved the perfect balance between permeability and selectivity when researching filter-feeding animals: Because of its high permeability, the ray can swiftly draw water into its mouth and expel it through its gills, allowing it to breathe in oxygen. In addition, it is extremely selective, filtering and consuming plankton instead of allowing the particles to pass through its gills.
The ray's filtering characteristics, the researchers discovered, are largely comparable to those of industrial cross-flow filters. These filters are made so that fluid passes over a permeable membrane, which allows the majority of the fluid to pass through, while any pollutants continue to pass through the membrane and finally exit into a waste reservoir.
The group pondered whether the mobula ray could serve as an inspiration for better industrial cross-flow filter designs. They did it by delving further into the dynamics of mobula ray filtration.
The team created a straightforward filter based on the mobula ray as part of their latest investigation. The filter's architecture is essentially a pipe with holes along its sides, or what engineers call a "leaky channel." The team's "channel" in this instance is made up of two clear, flat acrylic plates that are adhered to one another at the edges and have a little gap between them that allows fluid to be pumped through. The researchers placed 3D-printed structures at one end of the tube that resembled the grooved plates that run along the mobula ray's mouth floor.
In order to visualize the flow, the team then pumped water through the pipe at different rates while adding colored dye. Photographing the channel, they saw an intriguing change: the flow was "very peaceful" at low pumping rates, and fluid flowed readily between the printed plates' grooves and out into a reservoir. The faster-flowing fluid did not slide through when the researchers increased the pumping rate; instead, it seemed to swirl at the opening of each groove, forming a vortex that resembled a little knot of hair between the tips of a comb's teeth.
According to Hosoi, "this vortex is blocking particles, not water." At faster flow rates, particles attempt to pass through the filter but are thwarted by this vortex and are instead blasted down the channel, whereas at a slower flow, particles pass through the filter with the water. Because it stops particles from flowing out, the vortex is useful.
The researchers created a cross-flow filtration plan using the dimensions of the mobula rays' filtering properties and the outcomes of their trials.
Mao says, "We have given useful advice on how to really filter as the mobula ray does."
According to Hosoi, "you want to design a filter and be in the regime where you generate vortices." According to our instructions, your filter must have a specific pore diameter and spacing in order to create vortices that will filter out particles of this size if you want your plant to pump at a specific rate. We have a really useful guideline for rational design from the mobula ray.
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A New Health Tracker Powered by Sunlight and Sweat
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Posted by Okachinepa on 12/10/2024 @


Courtesy of SynEvol
Credit :Jihong Min
Similar to blood, sweat contains important health information, but it is much less intrusive to collect. Wei Gao, an assistant professor of medical engineering at Caltech, an investigator at the Heritage Medical Research Institute, and a Ronald and JoAnne Willens Scholar, developed wearable sweat sensors based on this idea.
Gao has improved these wearables over the last five years to identify a variety of health indicators, such as sugars, salts, uric acid, vitamins, amino acids, and even complicated compounds like C-reactive protein, which indicates specific health risks. In his most recent invention, Gao has fitted these sensors with a flexible solar cell for continuous, battery-free functioning. This was created in partnership with Martin Kaltenbrunner's group at Johannes Kepler University Linz in Austria.

Courtesy of SynEvol
Credit: Stepan Demchyshyn
The solar cell used by Gao’s lab is made of perovskite crystal, a material that shares the chemical structure first found in the mineral calcium titanium oxide. For a number of reasons, perovskite has drawn interest from solar cell developers. First, it is cheaper to manufacture than silicon (the primary material used in solar cells since the 1950s), which must be highly purified through multiple processes. Second, perovskite is as much as 1,000 times thinner than silicon solar cell layers, making them “quasi-2D” in Gao’s terms. Third, perovskite can be tuned to the spectra of different lighting, from outdoor sunlight to various forms of indoor lighting. Finally, and most enticingly for pioneers of solar energy, perovskite solar cells achieve a higher power conversion efficiency (PCE) than silicon, which enables them to produce more useful electricity from the light they receive.
In normal operation, the range is between 18 and 22 percent, however silicon solar cells have achieved PCE levels that range from 26 to 27 percent. In contrast, Gao's wearable sweat sensor's flexible perovskite solar cell (FPSC) boasts a record-breaking PCE of more than 31% when exposed to indoor light. Gao says, "We don't want to power our wearables only with strong sunlight." "Normative lighting in homes and offices is one of the more realistic conditions that we worry about. Strong sunshine increases the efficiency of many solar cells, but dim inside lighting does not. Gao claims that because "the spectral response of the FPSC matches well with the common indoor lighting emission spectrum," the sweat sensor's FPSC is especially well adapted to indoor lighting.

Courtesy of SynEvol\
Credit:Jihong Min
Gao's wearable sweat sensors were previously powered by large, cumbersome lithium-ion batteries that required external electricity to replenish. Gao's lab experimented with silicon solar cells in an attempt to find a lighter, more sustainable electricity source to power these high-demand gadgets, but they discovered that these cells were too inflexible, inefficient, and dependent on intense lighting. Additionally, they experimented with using body motion and the chemicals in human sweat (a readily available biofuel) to capture energy, but they discovered that these were either too unstable or needed too much work from the wearer.
Use of a FPSC has allowed Gao to create sweat sensors that can be worn for 12 hours a day, providing continuous monitoring of pH, salt, glucose, and temperature, and periodic monitoring (every five to 10 minutes) of sweat rate. Batteries or a specialized light source are not needed to achieve any of this. Furthermore, as the power source has become lighter and less cumbersome, the wearable has room for additional detectors to monitor a greater number of biomarkers simultaneously.

Courtesy of SynEvol
Credit: Jihong Min
Like its predecessors, this new wearable sweat sensor is put together like an origami, with distinct layers for various functions. There are four main interacting parts to the sensor. The first is dedicated to power management—disbursing the electricity harvested by the solar cell. The second enables iontophoresis, the induction of sweating without any exercise or exposure to high heat required on the part of its wearer. In Gao’s study, iontophoresis was performed every three hours to ensure that enough sweat was available to continuously monitor the biomarkers under observation. The third enables the electrochemical measurement of various substances in the sweat. The fourth manages data processing and wireless communication, which allows the sensor to interface with a cellphone app to display the ongoing results of the monitoring of sensors.
The sensor is 20 x 27 x 4 millimeters when fully built, and it is capable of withstanding the mechanical strain that comes with being worn on the body. Gao continues, "The majority of the sweat sensor's components, including the electronics and the FPSC, are reusable." “The only exception is the sensor patch, which is disposable, and it can be mass produced at a low cost using inkjet printing.” These sensor patches can also be customized according to what substances the user wishes to measure in their body.
As these solar-powered sweat sensors are put to use, they will be able to measure far more than any fitness or health tracker currently does. For example, they can be used for diabetes management (studies have shown that glucose in sweat is closely matched to glucose in the blood) and for the detection of a range of conditions such as heart disease, cystic fibrosis, and gout. Because they are noninvasive and can perform multiple measurements over short periods of time, these sensors can discern an individual’s baseline for substances such as cortisol, hormones, or the metabolites of various nutrients and medicines. Once the baseline levels for such substances are known, future deviations from these will provide a more effective means of diagnosis than a single Never could a blood draw. Additionally, it is hoped that the sensors, which are reasonably priced, would be a great diagnostic tool everywhere, even in underdeveloped nations.
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AI Unlocks Crystal Patterns to Drive Innovations of the Future
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Posted by Okachinepa on 12/09/2024 @


Courtesy of SynEvol:
Credit:University of Reading
To forecast how atoms would arrange themselves in crystal structures, a novel artificial intelligence model called CrystaLLM has been created. This innovation may hasten the development of novel materials for solar cells, computer chips, and batteries, among other technologies.
CrystaLLM, developed by researchers at the University of Reading and University College London, functions similarly to artificial intelligence chatbots in that it analyzes millions of crystal structures to learn the "language" of crystals.
The technology will be made available to the scientific community to help advances in material discovery after being published today (December 6) in Nature Communications.
Predicting crystal formations is similar to solving a challenging, multifaceted jigsaw with hidden components, according to Dr. Luis Antunes, who oversaw the study while doing his PhD at the University of Reading. Predicting crystal structures involves testing innumerable atom configurations, which demands enormous processing power.
Similar to a skilled puzzle solver who identifies winning patterns rather than attempting every potential move, "CrystaLLM offers a breakthrough by studying millions of known crystal structures to understand patterns and predict new ones."
Currently, the method for determining how atoms will form crystals is based on laborious computer simulations of the atoms' physical interactions. CrystaLLM functions more simply. It learns by scanning millions of crystal structure descriptions included in Crystallographic Information Files, the standard format for representing crystal structures, rather than by doing intricate physics computations.
These crystal descriptions are handled by CrystaLLM in the same way as text. It gradually picks up patterns about the structure of crystals as it reads each description and makes predictions about what will happen next. The system learned the physics and chemistry rules on its own without ever being taught them. Just reading these descriptions taught it things like how atoms arrange themselves and how their size influences the structure of the crystal.
Even with materials that CrystaLLM has never encountered before, it was able to produce realistic crystal formations during testing.
The research team has developed a free website that allows researchers to generate crystal structures using CrystaLLM. Better batteries, more effective solar cells, and speedier computer processors might all be developed more quickly if this model is incorporated into crystal structure prediction workflows.
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Lithium Batteries' Energy Can Be Tripled Using Carbon Nanotubes.
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Posted by Okachinepa on 12/09/2024 @


Courtesy of SynEvol
Credit:Preety Ahuja
Twisted carbon nanotubes can store three times as much energy per unit mass as sophisticated lithium-ion batteries, according to a global team of scientists that includes two researchers from the University of Maryland Baltimore County's Center for sophisticated Sensor Technology (CAST). This innovation makes carbon nanotubes a viable option for energy storage in small, light, and secure devices such as sensors and medical implants. Nature Nanotechnology recently published the results.
Sanjeev Kumar Ujjain from CAST, Katsumi Kaneko from Shinshu University in Nagano, Japan, and Shigenori Utsumi from Suwa University of Science in Chino, Japan, led the four universities that collaborated on the project. The project was started at Shinshu University by Kumar Ujjain, who carried on working on it after joining UMBC in 2022. Another CAST employee, Preety Ahuja, was essential in the research's material characterisation stage.
Single-walled carbon nanotubes, which resemble straws and are composed of pure carbon sheets that are just one atom thick, were the subject of the study. About 100 times stronger than steel, carbon nanotubes are also lightweight and reasonably simple to make. Because of their remarkable qualities, scientists are investigating how they may be used in a variety of futuristic-sounding technologies, such as space elevators.
The researchers at UMBC and its associates created carbon nanotube "ropes" using bundles of commercially available nanotubes in order to study the potential of carbon nanotubes for energy storage. The researchers coated the tubes with various materials meant to improve the strength and flexibility of the ropes after pulling and twisting them into a single thread.
The researchers calculated how much energy they could store by twisting the ropes up and measuring the energy released as they unfolded. The best-performing ropes were found to hold 15,000 times the energy per unit mass of steel springs and nearly three times the energy of lithium-ion batteries. At temperatures between -76 and +212 °F (-60 and +100 °C), the stored energy is stable and accessible. Furthermore, the carbon nanotube ropes are safer for human health than the materials used in batteries.
According to Kumar Ujjain, "mechanical coil springs have long been used by humans to store energy and power devices like watches and toys." “This research shows twisted carbon nanotubes have great potential for mechanical energy storage, and we are excited to share the news with the world.” He says the CAST team is already working to incorporate twisted carbon nanotubes as an energy source for a prototype sensor they are developing.
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Researchers Find a Way to Reduce the Size of Quantum Computer Components
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Posted by Okachinepa on 12/04/2024 @


Courtesy of SynEvol
Credit: NTU Singapore
Researchers have found a way to reduce the size of quantum computing, possibly reducing the equipment needed and downsizing key components by a factor of 1,000.
A new kind of quantum computers is based on light particles called photons, which are made in pairs and are referred to be "entangled" in quantum physics. These photons can be created, for example, by shining a laser on millimeter-thick crystals and using optical equipment to make sure the photons link. The fact that it is too large to fit inside a computer chip is a disadvantage of this strategy.
Scientists at Nanyang Technological University, Singapore (NTU Singapore) have now discovered a solution to the issue with this method by creating linked pairs of photons using materials that are 80 times thinner than a hair strand, or only 1.2 micrometers thick. Additionally, they accomplished this without requiring extra optical equipment to keep the connection between the photon pairs, which simplified the setup process overall.

Courtesy of SynEvol
Credit: NTU Singapore
According to Prof. Gao Weibo of NTU, who lead the team, "our novel method to create entangled photon pairs paves the way for making quantum optical entanglement sources much smaller, which will be critical for applications in quantum information and photonic quantum computing."
Since many of these devices now require enormous, bulky optical equipment that is difficult to align before they can function, he added, the technology could reduce the size of devices for quantum applications.
By doing intricate calculations and swiftly identifying patterns in massive data sets, quantum computers are predicted to completely transform how we tackle a variety of problems, from improving our understanding of climate change to accelerating the discovery of novel medications. For example, quantum computers could do computations in minutes that would take today's supercomputers millions of years to complete.
Since quantum computers execute multiple computations at once rather than one at a time like conventional computers do, this is to be expected.

Courtesy of SynEvol
Credit: NTU Singapore
This is possible because quantum computers use microscopic switches known as quantum bits, or qubits, that may be in both the on and off positions at the same time to execute computations. The spinning coin is in a stage between heads and tails, much like when you flip a coin in the air. Standard computers, on the other hand, have switches that can only be turned on or off at any given moment.
Because photons can be in both on and off states simultaneously, they can be employed as qubits in quantum computers to speed up computations. However, being in two states at the same time only occurs when two photons are created, one of which is entangled with the other. The synchronized vibrations of the paired photons are a crucial prerequisite for entanglement.
The ability to create and entangle photons at ambient temperature is one benefit of employing them as qubits. Therefore, relying on photons can be simpler, less expensive, and more useful than employing other particles, such as electrons, which require extremely low temperatures that are similar to those found in space in order to be used for quantum computing.

Courtesy of SynEvol
Credit: NTU Singapore
In order to incorporate connected pairs of photons into computer processors, researchers have been looking for smaller materials. One problem, though, is that materials produce photons at a considerably lower rate as they go thinner, making them unsuitable for computing.
Recent developments demonstrated that, despite its thinness, niobium oxide dichloride, a potential new crystalline material with special optical and electrical properties, can efficiently create pairs of photons. However, since these photon pairs are not entangled when they are created, they are of no service to quantum computers.
Together with Prof. Liu Zheng from the School of Materials Science & Engineering, NTU experts lead by Prof. Gao from the University's School of Electrical & Electronic Engineering and School of Physical & Mathematical Sciences came up with a solution.
An established technique for producing entangled pairs of photons with bulkier and thicker crystalline materials was reported in 1999 and served as the model for Prof. Gao's approach. Two thick crystal flakes are stacked together, and the crystalline grains of each flakes are oriented perpendicular to one another.
However, because of the way photons move through the thick crystals after they are formed, the vibrations of a pair of photons may still be out of sync. In order to preserve the connection between the light particles, additional optical equipment is required to synchronize the photon pairs.
According to Prof. Gao's theory, the connected photons might be produced without the need for additional optical equipment by using a comparable two-crystal setup with two thin crystal flakes of niobium oxide dichloride, which have a combined thickness of 1.2 micrometers.
Since the flakes utilized are significantly smaller than the heavier crystals from previous research, he anticipated this to occur. As a result, the pairs of photons produced travel a smaller distance within the niobium oxide dichloride flakes, so the light particles remain in sync with each other. Experiments by the NTU Singapore team proved that his hunch was correct.
Entangled photons are similar to synchronized clocks that display the same time regardless of their distance from one another, allowing for instant communication, according to Prof. Sun Zhipei of Finland's Aalto University, a photonics expert who was not involved in NTU's study.
The technique used by the NTU team to produce quantum entangled photons "is a major advancement, potentially enabling the miniaturization and integration of quantum technologies," he continued.
According to Prof. Sun, a co-principal investigator at the Research Council of Finland's Center of Excellence in Quantum Technology, "this development has potential to advance quantum computing and secure communication, as it allows for more compact, scalable, and efficient quantum systems."
In order to produce even more linked pairs of photons than are now feasible, the NTU team intends to further improve the setup.
One possibility is to investigate whether adding minute grooves and patterns to the surface of flakes of niobium oxide dichloride can boost the quantity of photon pairs generated. Another will investigate whether photon production may be increased by stacking the flakes of niobium oxide dichloride with other materials.
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