[Image above] Credit: NIST
Researchers report the creation of an ultrathin, fabric circuit that keeps high conductivity even while bending and stretching as much as yoga pants. The fiber’s core mimics spandex, consisting of an elastic polyurethane thread twinned by two cotton yarns. These stretchy strings were then dipped in silver nanoparticles to instill conductivity and then liquid silicone to encase everything. This silver nanoyarn could stretch as much as spandex—500% of its original length—and retain a high conductivity.
Using a mixture of laboratory tests and field trials, the team from the University of Sheffield has shown that when tampons are suspended in water contaminated by even very small amounts of detergents or sewage, they will pick up optical brighteners and glow under UV light. Optical brighteners—chemicals commonly used in toilet paper, laundry detergents, and shampoos—are a measure of sewage pollution, so the tampons offer a cheap and easy method of detection.
Cellulose nanocrystals derived from industrial byproducts have been shown to increase the strength of concrete, representing a potential renewable additive to improve the ubiquitous construction material. Cellulose nanocrystals—refined from byproducts generated in the paper, bioenergy, agriculture and pulp industries—are extracted from structures called cellulose microfibrils, which help to give plants and trees their high strength, lightweight, and resilience. Now, researchers at Purdue University have demonstrated that the cellulose nanocrystals can increase the tensile strength of concrete by 30 percent.
Molybdenum disulfide has an inherent issue that’s steeped in irony—the material’s greatest asset, its monolayer thickness, is also its biggest challenge. Researchers at Northwestern University tackled this problem by combining nanotechnology, materials science, and plasmonics to design and fabricate a series of silver nanodiscs and arrange them in a periodic fashion on top of a sheet of MoS2. Not only did they find that the nanodiscs enhanced light emission, but they determined the specific diameter of the most successful disc, which is 130 nm.
A pair of common kitchen ingredients inspired Cornell researchers’ improvement of the performance of lithium-sulfur batteries, a promising alternative to today’s lithium-ion batteries. The researchers report breakthroughs in the durability and performance of lithium-sulfur battery cathodes, one by using a component of corn starch, and the other, by modeling a nanocomposite material after the yolk-shell structure of eggs.