Bacteria-killing gel heals itself while healing you

Phys.org  July 25, 2019 Researchers in Canada report hierarchically structured hydrogels of self-organized M13 bacteriophage bundles, composed of hundreds of M13 nanofilaments, which exhibit both long-range and micron-scale order, are visible in electron micrographs of the cross-linked state. They adsorb up to 16× their weight in water, exhibit advanced properties at room temperature, namely, self-healing under biological conditions, autofluorescence in three channels, which decays through biodegradation, potentiating non-destructive imaging capability, and bioactivity toward the host bacteria. The latter is a powerful property, allowing the development of hydrogels with tunable bioactivity when combined with the phage display and/or recombinant DNA technology. […]

A hybrid material that switches reversibly between two stable solid states

Phys.org  August 7, 2019 To obtain dual stable states, the underlying mechanism must form an energy barrier between the two, where each state rested at an energetic minimum. An international team of researchers (Canada, USA – Case Western Reserve University, Louis Stokes Cleveland DVA Medical Center, University of Pittsburgh, Carnegie Mellon University) prepared sal-gel by mixing melted sodium acetate trihydrate with polymer pre-cursors of poly(acrylic acid) and a liquid mixture of acetic acid with water. The resulting gel mixture remained transparent, suggesting the constituents to be miscible with each other. The resulting gel had two solid states; a transparent soft […]

New process discovered to completely degrade flame retardant in the environment

EurekAlert  August 8, 2019 Among the most common flame retardants that hinder combustion and slow the spread of fire, tetrabromobisphenol A (TBBPA) is added to manufactured materials, including computer circuit boards and other electrical devices, papers, textiles and plastics. With a variety of health concerns, including cancer and hormone disruption, TBBPA has been widely detected in the environment, as well as in animals and human milk and plasma. It is a persistent global pollutant nontoxic. An international team of researchers (USA – UMass Amherst, China) has developed a process that breaks down TBBPA to harmless carbon dioxide and water. The […]

Physicists make graphene discovery that could help develop superconductors

EurekAlert  August 1, 2019 An international team of researchers (USA – Rutgers University, Japan) studied twisted bilayer graphene, created by superimposing two layers of graphene and slightly misaligning them. This creates a “twist angle” that results in a moiré pattern which changes rapidly when the twist angle changes and have a dramatic effect on the electronic properties of the material. This is because the moiré pattern slows down the electrons that conduct electricity in graphene and zip past each other at great speeds. At a twist angle of about 1.1 degrees – the so-called magic angle – the electrons come […]

Experimental observation of a new class of materials: Excitonic insulators

Science Daily  July 31, 2019 In a new study researchers in Australia have found evidence of a new phase of matter predicted in the 1960s: the excitonic insulator. It is a new phase of matter in the critical transition point between insulator and metal. The researchers studied antimony nanoflake using scanning tunneling microscopy and spectroscopy. They observed the unique feature of the excitonic insulator, a charge density wave (CDW) without periodic lattice distortion and a gap induced by the CDW near the Fermi surface, suggesting that the antimony (Sb(110)) nanoflake is an excitonic insulator. They are predicted to host many […]

Single-electrode material streamlines functions into a tiny chip

Phys.org  July 29, 2019 An international team of researchers (Saudi Arabia, USA – Georgia Institute of Technology) has demonstrated transistor‐level integration of electrochemical microsupercapacitors and thin film transistor rectifiers using ruthenium oxide as the common electrode material connecting all devices in the microcircuits. Thin film rectifiers are shown to be capable of rectifying AC signal input from either triboelectric nanogenerators or standard function generators. They exhibit exceptionally slow self‐discharge rate and sufficient power to drive various electronic devices. The study opens a new avenue for developing compact on‐chip electrochemical micropower units integrated with thin film electronics, simplifying device fabrication and […]

New low-cost thermoelectric material works at room temperature

Science Daily  July 22, 1019 The widespread adoption of thermoelectric devices that can directly convert electricity into thermal energy for cooling and heating has been hindered by the lack of materials that are both inexpensive and highly efficient at room temperature. A team of researchers in the US (University of Houston, MIT) has created an n-type material comprised of magnesium and bismuth. To produce a thermoelectric module using the new material, they combined it with a p-type version of the traditional bismuth-tellurium alloy. This allowed them to use just half as much tellurium as most current modules. The n-type Mg3Bi2-based […]

Extremely hard yet metallically conductive: Researchers develop novel material with high-tech prospects

Phys.org  July 8, 2019 An international team of researchers (Germany, Russia, Sweden, USA – University of Chicago, France) has developed a route to scale up the synthesis of rhenium nitride pernitride through a reaction between rhenium and ammonium azide, in a large-volume press at 33 GPa. Although metallic bonding is typically seen incompatible with intrinsic hardness, Re2(N2)(N)2 turned to be at a threshold for super hard materials. The process can be used for the synthesis of other nitrides, in particular nitrides of transition metals, which could also have technologically important properties…read more. Open Access TECHNICAL ARTICLE 

Found: A sweet way to make everyday things almost indestructible

Science Daily  June 27, 2019 An international team of researchers (USA – University of Virginia, University of Washington, Brookhaven National Laboratory, industry, University of Minnesota, USAID, UT Austin, Colorado State University, the Netherlands, France, UK, Tanzania, Switzerland, Italy) found that organisms that live in harsh environments have a pili on the surface. Pili, which are protein filaments, normally would be very sensitive to heat, acid and enzymes, but coating it in sugars make it almost indestructible. The sugars were arranged in such a stable fashion that even acid can’t dissolve them. According to the team coating materials with the special […]

Superhydrophobic ‘nanoflower’ for biomedical applications

Science Daily  July 2, 2019 Current superhydrophobic materials require alteration to the chemistry or topography of the surface to work which limits their use. Researchers at Texas A&M adopted a ‘nanoflower-like’ assembly of Molybdenum disulfide (MoS2) atomic layers to protect the surface from wetting. With their hexagonal packed layer 2D materials repel water adherence, however, a missing atom from the top layer can allow easy access to water molecules by the next layer of atoms underneath making it transit from hydrophobic to hydrophilic. For biomedical applications specifically, the study demonstrated that blood and cell culture media containing proteins do not […]