Fire researchers will tell you that there’s a simple solution for reducing fire hazards: eliminate flammable materials. If it doesn’t burn, the experts say, then there won’t be a fire.
Of course, that option isn’t very practical or realistic; after all, who wants to sit on a block of cement when you can have a cushiony recliner?
A better strategy for reducing the thousands of deaths and injuries and billions of dollars in damage resulting from the more than a million fires each year in the United States is detailed in a new research roadmap published by the National Institute of Standards and Technology (NIST). The roadmap provides guidelines for developing science-based approaches to solving numerous fire problems for multiple materials, from lightweight automobile composites to cross-laminated timbers, and prioritizes the most critical and urgent fire hazards to which... more
Rice University researchers enhance boron nitride nanotubes for next-gen composites
Boron nitride nanotubes are primed to become effective building blocks for next-generation composite and polymer materials based on a new discovery at Rice University – and a previous one.
Scientists at known-for-nano Rice have found a way to enhance a unique class of nanotubes using a chemical process pioneered at the university. The Rice lab of chemist Angel Martí took advantage of the Billups-Birch reaction process to enhance boron nitride nanotubes.
The work is described in the American Chemical Society journal ACS Applied Nano Materials.
Boron nitride nanotubes, like their carbon cousins, are rolled sheets of hexagonal arrays. Unlike carbon nanotubes, they’re electrically insulating... more
A 10-fold increase in the ability to harvest mechanical and thermal energy over standard piezoelectric composites may be possible using a piezoelectric ceramic foam supported by a flexible polymer support, according to Penn State researchers.
In the search for ways to harvest small amounts of energy to run mobile electronic devices or sensors for health monitoring, researchers typically add hard ceramic nanoparticles or nanowires to a soft, flexible polymer support. The polymer provides the flexibility, while the piezo nanoparticles convert the mechanical energy into electrical voltage. But these materials are relatively inefficient, because upon mechanical loading the mechanical energy is largely absorbed by the bulk of the polymer, with a very small fraction transferred to the piezo nanoparticles. While adding more ceramic would increase the energy efficiency, it comes with the tradeoff of less flexibility.
"The hard ceramics... more
Rutgers University–New Brunswick engineers have created a 3D-printed smart gel that walks underwater and grabs objects and moves them.
The watery creation could lead to soft robots that mimic sea animals like the octopus, which can walk underwater and bump into things without damaging them. It may also lead to artificial heart, stomach and other muscles, along with devices for diagnosing diseases, detecting and delivering drugs and performing underwater inspections.
Soft materials like the smart gel are flexible, often cheaper to manufacture than hard materials and can be miniaturized. Devices made of soft materials typically are simple to design and control compared with mechanically more complex hard devices.
“Our 3D-printed smart gel has great potential in biomedical engineering because it resembles tissues in the... more
Researchers discover that cresols disperse carbon nanotubes at unprecedentedly high concentrations
Northwestern University’s Jiaxing Huang is ready to reignite carbon nanotube research. And he’s doing so with a common chemical that was once used in household cleaners.
By using an inexpensive, already mass produced, simple solvent called cresol, Huang has discovered a way to make disperse carbon nanotubes at unprecedentedly high concentrations without the need for additives or harsh chemical reactions to modify the nanotubes. In a surprising twist, Huang also found that as the nanotubes’ concentrations increase, the material transitions from a dilute dispersion to a thick paste, then a free-standing gel and finally a kneadable dough that can be shaped and molded.
The study was... more
Researchers from the Laboratory of Organic Electronics at LiU have developed a fuel cell that uses lignin, a cheap by-product from paper manufacture and one of the most common biopolymers.
Approximately 25% of a tree is lignin – a biopolymer that glues the cellulose fibres together to form strong and durable wood. During the chemical manufacture of paper pulp this lignin is dissolved in either the sulphate or sulphite process, since the cellulose is the desired component for making paper.
Lignin is cheap and readily available. It is a biopolymer that consists of a large number of hydrocarbon chains woven together, which can be broken down in an industrial process to its energy-rich constituent parts, benzenediols. One of these, catechol makes up 7% of lignin. Researchers at the Organic Energy Materials group at LiU, led by Professor Xavier Crispin, have discovered that this... more
It’s common to see line-shaped clouds in the sky, known as contrails, trailing behind the engines of a jet airplane. What’s not always visible is a vortex coming off of the tip of each wing—like two tiny horizontal tornadoes—leaving behind a turbulent wake behind the vehicle.
The wake poses a destabilizing flight hazard, particularly for smaller aircraft that share the same flight path.
Recent research at the University of Illinois demonstrated that, although most wing shapes used today create these turbulent wake vortices, wing geometrics can be designed to reduce or eliminate wingtip vortices almost entirely. In the study, the vortex and wake characteristics were computed for three classic wing designs: the elliptic wing, and wing designs developed in classic studies by R.T. Jones and Ludwig Prandt.
“The elliptic wing configuration has been used as the gold standard of aerodynamic efficiency for the better part of a century. We teach our students that... more
A fast and safe method to prepare a 3D porous material that mimics the shape of a honeycomb could have broad applications from catalysis to drug delivery or for filtering air to remove pollutants or viruses.
The lattice of a honeycomb or the symmetry of a diatom are among complex living structures whose patterns and shapes have long inspired scientists. One recent application is to develop artificial hierarchical porous materials that are stable, yet have a large surface area and the ability to selectively extract materials. The complexity and pattern repeatability across scales from individual compartments to the entire structure, have made it difficult to build them at the nanoscale.
A team from KAUST, led by Suzana Nunes, has proposed a simple method that, in just five minutes, can produce a flexible film with a complex hierarchical structure that has repeating patterns of interconnected... more
Say goodbye to the slogan “diamonds are forever.” For industries that use dry lubricant, the up-and-coming phrase is more likely to be “broken nanodiamonds are forever.”
Researchers at the U.S. Department of Energy’s (DOE) Argonne National Laboratory are combining nanodiamonds with two-dimensional molybdenum disulfide layers and breaking them to create a self-generating, very-low-friction dry lubricant that lasts so long it could almost be confused with forever. The substance could have hundreds of industrial applications and can be used virtually wherever two pieces of metal rub together in dry conditions.
The most commonly used solid lubricants on the market today take the form of graphite paste. We use these lubricants to grease doorknobs and bike chains, among other things.
In 2015, Anirudha Sumant of the Nanoscience and Technology division and his... more
Pharmaceuticals owe their effects mostly to their chemical composition, but the packaging of these drugs into specific physical formulations also needs to be done to exact specifications.
For example, many drugs are encapsulated in solid microparticles, the size and shape of which determine the timing of the drug’s release and its delivery to specific parts of the body.
When engineering these drug microparticles, consistency is key, but common drug manufacturing techniques, such as spray drying and ball milling, produce uneven results. The ideal method involves microfluidics, a kind of liquid assembly line that drips out perfectly sized microparticles one at a time.
Now, University of Pennsylvania engineers have developed a microfluidic system where more than 10,000 of these devices run in parallel, all on a silicon-and-glass chip that can fit into a shirt pocket... more