New York | Heidelberg, 24 September 2014 - Electronic transport in graphene contributes to its characteristics. Now, a Russian scientist proposes a new theoretical approach to describe graphene with defects—in the form of artificial triangular holes—resulting in the rectification of the electric current within the material. Specifically, the study provides an analytical and numerical theory of the so-called ratchet effect.
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Edmonton—Cleaning up oil sands tailings has just gotten a lot greener thanks to a novel technique developed by University of Alberta civil engineering professors that uses solar energy to accelerate tailings pond reclamation efforts by industry.
Instead of using UV lamps as a light source to treat oil sands process affected water (OSPW) retained in tailings ponds, professors Mohamed Gamal El-Din and James Bolton have found that using the sunlight as a renewable energy source treats the wastewater just as efficiently but at a much lower cost.
Over one thousand miles wide and three thousand miles long, the Sargasso Sea occupies almost two thirds of the North Atlantic Ocean. Within the sea, circling ocean currents accumulate mats of Sargassum seaweed that shelter a surprising variety of fishes, snails, crabs, and other small animals. A recent paper by MBARI researcher Crissy Huffard and others shows that in 2011 and 2012 this animal community was much less diverse than it was in the early 1970s, when the last detailed studies were completed in this region.
Thermal energy storage is a common strategy in energy production systems in which the period of production does not coincide with that of consumption. This happens with the production of hot water by means of solar thermal panels, for example; here, hot water is produced during sunlight hours when demand is lower. It is also the case in residential cogeneration, where heat and electrical power are simultaneously generated but not so demand.
WASHINGTON, D.C., September 23, 2014—Researchers from the University of Texas at Austin and Northwestern University have demonstrated a new method to improve the reliability and performance of transistors and circuits based on carbon nanotubes (CNT), a semiconductor material that has long been considered by scientists as one of the most promising successors to silicon for smaller, faster and cheaper electronic devices. The result appears in a new paper published in the journal Applied Physics Letters, from AIP Publishing.
Arguments about whose turn it is to do the washing up, negotiating rights to the TV remote control and disputes over noise — as many students returning to university for the new academic year are about to learn the hard way, sharing a house can be a tricky business. And now research from academics at The University of Nottingham has revealed that new technology to allow people to monitor their energy usage in the home could be about to ratchet up the tension.
Manufacturing biofuels from food crop by-products such as straw could be made quicker and cheaper thanks to the work of scientists in the UK and France.
Researchers funded by the Biotechnology and Biological Sciences Research Council (BBSRC) have discovered variant straw plants whose cell walls are more easily broken down to make biofuels, but which are not significantly smaller or weaker than regular plants.
The discovery could help ease pressure on global food security as biofuels from non-food crops become easier and cheaper to make.
SALT LAKE CITY, Sept. 22, 2014 – University of Utah engineers discovered a way to create a special material – a metal layer on top of a silicon semiconductor – that could lead to cost-effective, superfast computers that perform lightning-fast calculations but don't overheat.
This new "topological insulator" behaves like an insulator on the inside but conducts electricity on the outside and may pave the way for quantum computers and fast spintronic devices.
RIVERSIDE, Calif. — Less supportive and punitive parenting techniques used by some Chinese parents might lead to the development of low self-esteem and school adjustment difficulties in their children and leave them vulnerable to depression and problem behaviors, according to a paper recently published by a University of California, Riverside assistant professor and other researchers.
Mobile robots could be much more useful in homes, if they could locate people, places and objects. Today's robots usually see the world with cameras and lasers, which have difficulty reliably recognizing things and can miss objects that are hidden in clutter. A complementary way robots can "sense" what is around them is through the use of small ultra-high frequency radio-frequency identification (UHF RFID) tags. Inexpensive self-adhesive tags can be stuck on objects, allowing an RFID-equipped robot to search a room for the correct tag's signal, even when the object is hidden out of sight.
In a big step for securing critical information systems, such as medical records in clinical settings, Dartmouth College researchers have created a new approach to computer security that authenticates users continuously while they are using a terminal and automatically logs them out when they leave or when someone else steps in to use their terminal.
Greenhouse gas emissions from the production and use of shale gas would be comparable to conventional natural gas, but the controversial energy source actually faired better than renewables on some environmental impacts, according to new research.
While public health authorities focus on the physical activity benefits of active play, a new study from the University of Montreal reveals that for children, playing has no goal – it is an end in itself, an activity that is fun, done alone or with friends, and it represents "an opportunity to experience excitement or pleasure, but also to combat boredom, sadness, fear, or loneliness." "By focusing on the physical activity aspect of play, authorities put aside several aspects of play that are beneficial to young people's emotional and social health," explains Professor Katherine Frohlich of
CAMBRIDGE, Mass-- A major limitation in the performance of solar cells happens within the photovoltaic material itself: When photons strike the molecules of a solar cell, they transfer their energy, producing quasi-particles called excitons — an energized state of molecules. That energized state can hop from one molecule to the next until it's transferred to electrons in a wire, which can light up a bulb or turn a motor.
New light has been shed on solar power generation using devices made with polymers, thanks to a collaboration between scientists in the University of Chicago's chemistry department, the Institute for Molecular Engineering, and Argonne National Laboratory.