News from the NNI Community - Research Advances Funded by Agencies Participating in the NNI

Plastics are a popular 3-D printing material, but printed parts are mechanically weak—a flaw caused by the imperfect bonding between the individual printed layers that make up the 3-D part. Now, researchers at Texas A&M University, in collaboration with scientists in the company Essentium, Inc. have developed a technology that overcomes this flaw. By integrating plasma science and carbon nanotube technology into standard 3-D printing, the researchers welded adjacent printed layers more effectively, increasing the overall reliability of the final part.

In 2018, MIT scientists discovered that when two sheets of graphene are stacked together at a slightly offset "magic" angle, the new "twisted" graphene structure can become either an insulator or a superconductor. Now, the MIT scientists report that they and others have imaged and mapped an entire twisted graphene structure for the first time at a resolution fine enough that they are able to see slight variations in the local twist angle across the entire structure. The scientists also reported creating a new twisted graphene structure with not two, but four layers of graphene. They observed that the new four-layer magic-angle structure is more sensitive to certain electric and magnetic fields compared to its two-layer predecessor. 

In 2018, MIT scientists discovered that when two sheets of graphene are stacked together at a slightly offset "magic" angle, the new "twisted" graphene structure can become either an insulator or a superconductor. Now, the MIT scientists report that they and others have imaged and mapped an entire twisted graphene structure for the first time at a resaolution fine enough that they are able to see slight variations in the local twist angle across the entire structure. The scientists also reported creating a new twisted graphene structure with not two, but four layers of graphene. They observed that the new four-layer magic-angle structure is more sensitive to certain electric and magnetic fields compared to its two-layer predecessor. 

Researchers at Rice University have found evidence of piezoelectricity in lab-grown, two-dimensional flakes of molybdenum dioxide that are less than 10 nanometers thick. Piezoelectricity is a property of materials that respond to stress by generating an electric voltage across their surfaces or generate mechanical strain in response to an applied electric field. The researchers found that the surprise electrical properties are due to electrons trapped in defects throughout the material.

Researchers at Rice University have found evidence of piezoelectricity in lab-grown, two-dimensional flakes of molybdenum dioxide that are less than 10 nanometers thick. Piezoelectricity is a property of materials that respond to stress by generating an electric voltage across their surfaces or generate mechanical strain in response to an applied electric field. The researchers found that the surprise electrical properties are due to electrons trapped in defects throughout the material.

Researchers at the University of Virginia are pioneering the use of focused ultrasound to defy the brain's protective barrier, so that doctors could deliver treatments directly into the brain. The approach could revolutionize treatment for brain cancer by using the focused ultrasound to deliver gene therapy via "deep-penetrating nanoparticles." The nanoparticles are engineered to penetrate the tissue, and the focused sound waves are able to open spaces between cells in the tissue.

Researchers at the University of Virginia are pioneering the use of focused ultrasound to defy the brain's protective barrier, so that doctors could deliver treatments directly into the brain. The approach could revolutionize treatment for brain cancer by using the focused ultrasound to deliver gene therapy via "deep-penetrating nanoparticles." The nanoparticles are engineered to penetrate the tissue, and the focused sound waves are able to open spaces between cells in the tissue.

Researchers at Texas A&M University have made mats that are strong, stable, and capable of delivering antioxidant activity for prolonged periods of time. Each mat is made of an intertwined network of ultra-fine strands of a polymer and an antioxidant found in red wine. In past studies, antioxidants were blended into synthetic mats, but the researchers said these mats have lower functionality because the surface area for antioxidant activity is limited. To increase the surface area for antioxidant activity, the researchers created an antioxidant mesh made with nanofibers of polymer and tannic acid.

Researchers at Texas A&M University have made mats that are strong, stable, and capable of delivering antioxidant activity for prolonged periods of time. Each mat is made of an intertwined network of ultra-fine strands of a polymer and an antioxidant found in red wine. In past studies, antioxidants were blended into synthetic mats, but the researchers said these mats have lower functionality because the surface area for antioxidant activity is limited. To increase the surface area for antioxidant activity, the researchers created an antioxidant mesh made with nanofibers of polymer and tannic acid.

A multi-institutional team of researchers led by Lawrence Livermore National Laboratory has developed a smart, breathable fabric designed to protect the wearer against biological and chemical warfare agents. The fabric combines two key elements: a base membrane layer made of trillions of aligned carbon nanotube pores and a polymer layer grafted onto the membrane layer. The carbon nanotubes are able to easily transport water molecules through their interiors while also blocking biological agents.