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Jun 22, 2022

Process to customize molecules does double duty

Posted by in categories: biotech/medical, chemistry

Inspired by your liver and activated by light, a chemical process developed in labs at Rice University and in China shows promise for drug design and the development of unique materials.

Researchers led by Rice chemist Julian West and Xi-Sheng Wang at the University of Science and Technology of China, Hefei, are reporting their successful catalytic process to simultaneously add two distinct functional groups to single alkenes, drawn from petrochemicals that contain at least one carbon-carbon double bond combined with .

Better yet, they say, is that these alkenes are “unactivated”—that is, they lack reactive atoms near the double bond—and until now, have proven challenging to enhance.

Jun 22, 2022

Tiny fish-shaped robot ‘swims’ around picking up microplastics

Posted by in categories: particle physics, robotics/AI

Microplastics are found nearly everywhere on Earth and can be harmful to animals if they’re ingested. But it’s hard to remove such tiny particles from the environment, especially once they settle into nooks and crannies at the bottom of waterways. Now, researchers in ACS’ Nano Letters have created a light-activated fish robot that “swims” around quickly, picking up and removing microplastics from the environment.

Because microplastics can fall into cracks and crevices, they’ve been hard to remove from aquatic environments. One that’s been proposed is using small, flexible and self-propelled robots to reach these pollutants and clean them up. But the used for soft robots are hydrogels and elastomers, and they can be damaged easily in aquatic environments. Another material called mother-of-pearl, also known as nacre, is strong and flexible, and is found on the inside surface of clam shells. Nacre layers have a microscopic gradient, going from one side with lots of calcium carbonate mineral-polymer composites to the other side with mostly a silk protein filler. Inspired by this , Xinxing Zhang and colleagues wanted to try a similar type of gradient structure to create a durable and bendable material for .

The researchers linked β-cyclodextrin molecules to sulfonated graphene, creating composite nanosheets. Then solutions of the nanosheets were incorporated with different concentrations into polyurethane latex mixtures. A layer-by-layer assembly method created an ordered concentration gradient of the nanocomposites through the material from which the team formed a tiny fish robot that was 15-mm (about half-an-inch) long. Rapidly turning a near-infrared light laser on and off at a fish’s tail caused it to flap, propelling the robot forward. The robot could move 2.67 body lengths per second—a that’s faster than previously reported for other soft swimming robots and that is about the same speed as active phytoplankton moving in water. The researchers showed that the swimming fish robot could repeatedly adsorb nearby polystyrene microplastics and transport them elsewhere. The material could also heal itself after being cut, still maintaining its ability to adsorb microplastics.

Jun 22, 2022

A universal approach to tailoring soft robots

Posted by in categories: 3D printing, biological, robotics/AI

By combining two distinct approaches into an integrated workflow, Singapore University of Technology and Design (SUTD) researchers have developed a novel automated process for designing and fabricating customized soft robots. Their method, published in Advanced Materials Technologies, can be applied to other kinds of soft robots—allowing their mechanical properties to be tailored in an accessible manner.

Though robots are often depicted as stiff, metallic structures, an emerging class of pliable machines known as is rapidly gaining traction. Inspired by the flexible forms of living organisms, soft robots have wide applications in sensing, movement, object grasping and manipulation, among others. Yet, such robots are still mostly fabricated through manual casting techniques—limiting the complexity and geometries that can be achieved.

“Most fabrication approaches are predominantly manual due to a lack of standard tools,” said SUTD Assistant Professor Pablo Valdivia y Alvarado, who led the study. “But 3D printing or additive manufacturing is slowly coming into play as it facilitates repeatability and allows more complex designs—improving quality and performance.”

Jun 22, 2022

Chicago Quantum Exchange takes first steps toward a future that could revolutionize computing and medicine

Posted by in categories: biotech/medical, business, computing, internet, quantum physics

Flashes of what may become a transformative new technology are coursing through a network of optic fibers under Chicago.

Researchers have created one of the world’s largest networks for sharing —a field of science that depends on paradoxes so strange that Albert Einstein didn’t believe them.

The network, which connects the University of Chicago with Argonne National Laboratory in Lemont, is a rudimentary version of what scientists hope someday to become the internet of the future. For now, it’s opened up to businesses and researchers to test fundamentals of quantum information sharing.

Jun 22, 2022

Using microbrewery waste to synthesize carbon quantum dots

Posted by in categories: biotech/medical, chemistry, nanotechnology, quantum physics

For a few years now, spent grain, the cereal residue from breweries, has been reused in animal feed. This material could also be used in nanotechnology. Professor Federico Rosei’s team at the Institut national de la recherche scientifique (INRS) has shown that microbrewery waste can be used as a carbon source to synthesize quantum dots. The work, done in collaboration with Claudiane Ouellet-Plamondon of the École de technologie supérieure (ÉTS), was published in the Royal Society of Chemistry’s journal RSC Advances.

Often considered “artificial atoms,” are used in the transmission of light. With a range of interesting physicochemical properties, this type of nanotechnology has been successfully used as a sensor in biomedicine or as LEDs in next generation displays. But there is a drawback. Current quantum dots are produced with heavy and toxic metals like cadmium. Carbon is an interesting alternative, both for its biocompatibility and its accessibility.

Jun 22, 2022

Organ storage a step closer with cryopreservation discovery

Posted by in categories: biotech/medical, chemistry, cryonics, finance, life extension

Australian scientists have taken the first step towards improved storage of human cells, which may lead to the safe storage of organs such as hearts and lungs.

The team’s discovery of new cryoprotective agents opens the door to many more being developed that could one day help to eliminate the need for organ transplant waiting lists. Their results are published in the Journal of Materials Chemistry B.

Cryopreservation is a process of cooling biological specimens down to very low temperatures so they can be stored for a long time. Storing cells through cryopreservation has had big benefits for the world—including boosting supplies at blood banks and assisting reproduction—but it is currently impossible to store organs and simple tissues.

Jun 22, 2022

Scientists observe longitudinal plasmonic field in nanocavity at subnano-scale

Posted by in categories: chemistry, nanotechnology

A group of scientists working on surface-enhanced Raman spectroscopy (SERS) has made a nanoruler to provide insight into the longitudinal plasmonic fields in nanocavities, according to research published in the Journal of the American Chemical Society.

SERS is a highly sensitive and powerful spectral analysis technique applicable in various fields. In to weak Raman scattering, SERS achieves a dramatically enhanced Raman signal of up to 1010–15, allowing the analysis of single molecules.

“How we develop the technology depends, to a large extent, on what we know about fields. In the experiments, we observed an uneven distribution in the plasmonic field at the nano-scale. But it lacks theoretic and experimental support. So we decided to figure it out,” said Yang Liangbao, who leads the team at the Hefei Institutes of Physical Science of the Chinese Academy of Sciences.

Jun 22, 2022

What did Megalodon eat? Anything it wanted, including other predators

Posted by in category: food

New Princeton research shows that prehistoric megatooth sharks—the biggest sharks that ever lived—were apex predators at the highest level ever measured.

Megatooth get their name from their massive teeth, which can each be bigger than a human hand. The group includes Megalodon, the largest shark that ever lived, as well as several related species.

While sharks of one kind or another have existed since long before the dinosaurs—for more than 400 million years—these megatooth sharks evolved after the dinosaurs went extinct and ruled the seas until just 3 million years ago.

Jun 22, 2022

Clean doping strategy produces more responsive phototransistors

Posted by in categories: chemistry, computing, engineering

The library of two-dimensional (2D) layered materials keeps growing, from basic 2D materials to metal chalcogenides. Unlike their bulk counterparts, 2D layered materials possess novel features that offer great potential in next-generation electronics and optoelectronics devices.

Doping engineering is an important and effective way to control the peculiar properties of 2D materials for the application in logical circuits, sensors, and optoelectronic devices. However, additional chemicals have to be used during the process, which may contaminate the materials. The techniques are only possible at specific steps during material synthesis or device fabrication.

In a new paper published in eLight, a team of scientists led by Professor Han Zhang of Shenzhen University and Professor Paras N Prasad of the University of Buffalo studied the implementation of neutron-transmutation doping to manipulate . Their paper, titled has demonstrated the change for the first time.

Jun 22, 2022

Building artificial nerve cells

Posted by in categories: biological, chemistry, computing, space

For the first time, researchers have demonstrated an artificial organic neuron, a nerve cell, that can be integrated with a living plant and an artificial organic synapse. Both the neuron and the synapse are made from printed organic electrochemical transistors.

On connecting to the carnivorous Venus flytrap, the electrical pulses from the artificial nerve cell can cause the plant’s leaves to close, although no fly has entered the trap. Organic semiconductors can conduct both electrons and ions, thus helping mimic the ion-based mechanism of pulse (action potential) generation in plants. In this case, the small electric pulse of less than 0.6 V can induce action potentials in the plant, which in turn causes the leaves to close.

“We chose the Venus flytrap so we could clearly show how we can steer the biological system with the artificial organic system and get them to communicate in the same language,” says Simone Fabiano, associate professor and principal investigator in organic nanoelectronics at the Laboratory of Organic Electronics, Linköping University, Campus Norrköping.