Washington State University researchers have created a sustainable alternative to traditional concrete using coal fly ash, a waste product of coal-based electricity generation.
The advance tackles two major environmental problems at once by making use of coal production waste and by significantly reducing the environmental impact of concrete production.
Xianming Shi, associate professor in WSU’s Department of Civil and Environmental Engineering, and graduate student Gang Xu, have developed a strong, durable concrete that uses fly ash as a binder and eliminates the use of environmentally intensive cement. They report on their work in the August issue of the journal, Fuel.
Reduces energy demand, greenhouse emissions
Production of traditional concrete, which is made by combining cement with sand and gravel, contributes between five and eight percent of greenhouse... more
Opening up a pathway to cost-effective, autonomous IoT application
Objects in our daily lives, such as speakers, refrigerators, and even cars, are becoming “smarter” day by day as they connect to the internet and exchange data, creating the Internet of Things (IoT), a network among the objects themselves. Toward an IoT-based society, a miniaturized thermoelectric generator is anticipated to charge these objects, especially for those that are portable and wearable.
Due to advantages such as its relatively low thermal conductance but high electric conductance, silicon nanowires have emerged as a promising thermoelectric material. Silicon-based thermoelectric generators conventionally employed long, silicon nanowires of about 10-100 nanometers, which were... more
Folding and cutting thin metal films could enable microchip-based 3-D optical devices.
Nanokirigami has taken off as a field of research in the last few years; the approach is based on the ancient arts of origami (making 3-D shapes by folding paper) and kirigami (which allows cutting as well as folding) but applied to flat materials at the nanoscale, measured in billionths of a meter.
Now, researchers at MIT and in China have for the first time applied this approach to the creation of nanodevices to manipulate light, potentially opening up new possibilities for research and, ultimately, the creation of new light-based communications, detection, or computational devices.
The findings are described today in the journal Science Advances, in a paper by MIT professor of mechanical... more
For the first time, researchers have created a nanocomposite of ceramics and a two-dimensional material, opening the door for new designs of nanocomposites with such applications as solid-state batteries, thermoelectrics, varistors, catalysts, chemical sensors and much more.
Sintering uses high heat to compact powder materials into a solid form. Widely used in industry, ceramic powders are typically compacted at temperatures of 1472 degrees Fahrenheit or higher. Many low-dimensional materials cannot survive at those temperatures.
But a sintering process developed by a team of researchers at Penn State, called the cold sintering process (CSP), can sinter ceramics at much lower temperatures, less than 572 degrees F, saving energy and enabling a new form of material with high commercial potential.
"We have industry people who are already very interested in this work," said Jing Guo, a post-doctoral scholar working in the group of Clive Randall, professor... more
Rice lab creates conductive 3D carbon blocks that can be shaped for applications
Rice University scientists have developed a simple way to produce conductive, three-dimensional objects made of graphene foam.
The squishy solids look and feel something like a child’s toy but offer new possibilities for energy storage and flexible electronic sensor applications, according to Rice chemist James Tour.
The technique detailed in Advanced Materials is an extension of groundbreaking work by the Tour lab that produced the first laser-induced graphene (LIG) in 2014 by heating inexpensive polyimide plastic sheets with a laser.
The laser burns halfway through the plastic and turns the top into interconnected flakes of 2D carbon that remain attached to the bottom half. LIG can... more
Jes Linnet, University of Southern Denmark
Researchers demonstrate silver-based electrode films that could be used for flexible touch displays, televisions and solar cells
Researchers have demonstrated large-scale fabrication of a new type of transparent conductive electrode film based on nanopatterned silver. Smartphone touch screens and flat panel televisions use transparent electrodes to detect touch and to quickly switch the color of each pixel. Because silver is less brittle and more chemically resistant than materials currently used to make these electrodes, the new films could offer a high-performance and long-lasting option for use with flexible screens and electronics. The silver-based films could also enable flexible solar cells for installation on windows, roofs and even personal devices.
In the journal Optical Materials Express, the researchers... more
University of Delaware/ Illustration by Joy Smoker
UD engineers convert commonly discarded material into high-performance adhesive
Whether you’re wrapping a gift or bandaging a wound, you rely on an adhesive to get the job done.
These sticky substances often are made from petroleum-derived materials, but what if there was a more sustainable way to make them? Now, a team of engineers at the University of Delaware has developed a novel process to make tape out of a major component of trees and plants called lignin—a substance that paper manufacturers typically throw away. What’s more, their invention performs just as well as at least two commercially available products.
The researchers recently described their results in ACS Central Science, and they are working on more ways to upcycle scrap wood and plants into... more
Ever wonder why paint peels off the wall during summer’s high humidity? It’s the same reason that bandages separate from skin when we bathe or swim.
Interfacial water, as it’s known, forms a slippery and nonadhesive layer between the glue and the surface to which it is meant to stick, interfering with the formation of adhesive bonds between the two.
Overcoming the effects of interfacial water is one of the challenges facing developers of commercial adhesives.
To find a solution, researchers here at The University of Akron are looking to one of the strongest materials found in nature — spider silk.
‘Nature’s best glue’
The sticky glue that coats the silk threads of spider webs is a hydrogel, meaning it is full of water. One would think, then, that spiders would have difficulty catching prey, especially in humid conditions... more
Waste heat can be converted to electricity more efficiently using one-dimensional nanoscale materials as thin as an atom – ushering a new way of generating sustainable energy – thanks to new research by the University of Warwick.
Led by Drs Andrij Vasylenko, Samuel Marks, Jeremy Sloan and David Quigley from Warwick’s Department of Physics, in collaboration with the Universities of Cambridge and Birmingham, the researchers have found that the most effective thermoelectric materials can be realised by shaping them into the thinnest possible nanowires.
Thermoelectric materials harvest waste heat and convert it into electricity - and are much sought-after as a renewable and environmentally friendly sources of energy.
Dr Andrij Vasylenko, from the University of Warwick’s Department of Physics and the paper’s first author, commented:
“In contrast to 3-dimensional material, isolated nanowires conduct less heat... more
A centuries-old materials bonding process is being tested aboard the International Space Station in an experiment that could pave the way for more materials research of its kind aboard the orbiting laboratory.
Sintering is the process of heating different materials to compress their particles together.
“In space the rules of sintering change,” said Rand German, principal investigator for the investigation titled NASA Sample Cartridge Assembly-Gravitational Effects on Distortion in Sintering (MSL SCA-GEDS-German). “The first time someone tries to do sintering in a different gravitational environment beyond Earth or even microgravity, they may be in for a surprise. There just aren’t enough trials yet to tell us what the outcome could be. Ultimately we have to be empirical, give it a try, and see what happens.”
If the disparities between sintering on Earth and sintering in space can be... more