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Archive for the ‘materials’ category: Page 287

Nov 25, 2015

Inkjet hologram printing now possible

Posted by in categories: chemistry, materials, security

Vivid holographic images and text can now be produced by means of an ordinary inkjet printer. This new method, developed by a team of scientists from ITMO University in Saint Petersburg, is expected to significantly reduce the cost and time needed to create the so-called rainbow holograms, commonly used for security purposes — to protect valuable items, such as credit cards and paper currency, from piracy and falsification. The results of the study were published 17 November in the scientific journal Advanced Functional Materials.

The team, led by Alexander Vinogradov, senior research associate at the International Laboratory of Solution Chemistry of Advanced Materials and Technologies (SCAMT) in ITMO University, developed colorless ink made of nanocrystalline titania, which can be loaded into an inkjet printer and then deposited on special microembossed paper, resulting in unique patterned images. The ink makes it possible to print custom holographic images on transparent film in a matter of minutes, instead of days as with the use of conventional methods.

Rainbow holograms are widely used to fight against the forgery of credit cards, money, documents and certain manufactured products that call for a high level of protection. Even though the technology of obtaining holographic images was already developed in the 1960s, there still exist numerous technical difficulties that impede its further spread and integration into polygraphic industry.

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Nov 25, 2015

‘Material universe’ yields surprising new particle

Posted by in categories: computing, materials, particle physics, quantum physics

An international team of researchers has predicted the existence of a new type of particle called the type-II Weyl fermion in metallic materials. When subjected to a magnetic field, the materials containing the particle act as insulators for current applied in some directions and as conductors for current applied in other directions. This behavior suggests a range of potential applications, from low-energy devices to efficient transistors.

The researchers theorize that the particle exists in a material known as tungsten ditelluride (WTe2), which the researchers liken to a “material universe” because it contains several , some of which exist under normal conditions in our universe and others that may exist only in these specialized types of crystals. The research appeared in the journal Nature this week.

The new particle is a cousin of the Weyl fermion, one of the particles in standard theory. However, the type-II particle exhibits very different responses to electromagnetic fields, being a near perfect conductor in some directions of the field and an insulator in others.

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Nov 23, 2015

Diamond Nanothreads Could Support Space Elevator

Posted by in categories: materials, space

A string of benzene molecules that’s 20,000 times smaller than a strand of human hair is the strongest material ever made.

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Nov 23, 2015

World’s first cyber-plants fuse electronics with roses

Posted by in categories: electronics, materials

For the first time, scientists have created analogue and digital electronic circuits inside living plants, using the vascular system of living roses to build – or rather ‘grow’ – the central components of electronic circuits.

Researchers at Linköping University in Sweden merged numerous electrical components inside the roses, including wires, digital logic, and even display-based elements, thanks to a special polymer that’s capable of acting like a wire while still transporting organic material such as water and nutrients through the rose’s stem.

By successfully incorporating electronics into the living systems of plants, it’s hoped we’ll be able to find out much more about the chemical processes and pathways that make them function – and we could even learn to control and manipulate them.

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Nov 20, 2015

From air to plastic

Posted by in category: materials

This plastic is made from thin air — and taking on a $373 billion dollar-a-year industry: http://cnnmon.ie/1I2paBM

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Nov 19, 2015

Breakthrough! Glasgow scientists discover a cheap way to produce the wonder material graphene

Posted by in categories: biotech/medical, cyborgs, materials, mobile phones

It has been hailed as a wonder material set to revolutionise everyday life, but graphene has always been considered too expensive for mass production – until now.

Scientists at Glasgow University have made a breakthrough discovery, allowing graphene to be produced one hundred times more cheaply than before, opening it up to an array of new applications.

First isolated in 2004, the miracle material can be used in almost anything from bendable mobile phone screens to prosthetic skin able to provide sensation.

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Nov 18, 2015

Smallest-possible Diamonds Form Ultra-thin Nanothread

Posted by in categories: materials, space

A team has, for the first time, discovered how to produce ultra-thin “diamond nanothreads” that promise extraordinary properties, including strength and stiffness greater than that of today’s strongest nanotubes and polymer fibers. Such exceedingly strong, stiff, and light materials have an array of potential applications, everything from more-fuel efficient vehicles or even the science fictional-sounding proposal for a “space elevator.”

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Nov 16, 2015

Graphene Could Give Us Sleek Night Vision Sensors

Posted by in categories: computing, electronics, materials, mobile phones

Because of its unique chemical and physical properties, graphene has helped scientists design new gadgets from tiny computer chips to salt water filters. Now a team of researchers from MIT has found a new use for the 2D wonder material: in infrared sensors that could replace bulky night-vision goggles, or even add night vision capabilities to high-tech windshields or smartphone cameras. The study was published last week in Nano Letters.

Night vision technology picks up on infrared wavelengths, energy usually emitted in the form of heat that humans can’t see with the naked eye. Researchers have known for years that because of how it conducts electricity, graphene is an excellent infrared detector, and they wanted to see if they could create something less bulky than current night-vision goggles. These goggles rely on cryogenic cooling to reduce the amount of excess heat that might muddle the image. To create the sensor, the researchers integrated graphene with tiny silicon-based devices called MEMS. Then, they suspended this chip over an air pocket so that it picks up on incoming heat and eliminates the need for the cooling mechanisms found in other infrared-sensing devices. That signal is then transmitted to another part of the device that creates a visible image. When the researchers tested their sensor, they found that it clearly and successfully picked up the image of a human hand.

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Nov 16, 2015

This new laser could make things hotter than the centre of the Sun almost instantly

Posted by in categories: materials, nuclear energy, sustainability

Scientists have proposed a laser model that can could heat materials to temperatures hotter than the centre of the Sun in just 20 quadrillionths of a second. That’s 10 million degrees Celsius almost instantaneously.

The discovery brings us one step closer to the dream of achieving thermonuclear fusion energy — the production of clean, sustainable, and limitless energy using the same process the Sun uses to produce heat.

The challenge in harnessing the energy from thermonuclear fusion is that, as with any form of energy production, you need to get out more than you put in, and heating things to temperatures that rival the centre of the Sun is not easy. Current laser technology has failed to make the heating process efficient enough to make the process worthwhile, but a team from Imperial College London in the UK has come up with a model for a laser than can heat things about 100 times faster than the world’s most powerful fusion experiments.

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Nov 12, 2015

Scientists develop ‘nanopores’ that inexpensively filter the salt out of seawater

Posted by in categories: energy, engineering, materials

There’s filtration and then there’s filtration. Engineers in the US have been working on the latter, coming up with a new markedly more energy-efficient way of taking the salt out of seawater, which could deliver huge advantages in terms of providing people with access to drinking water and help combat problems like drought.

The researchers have developed a material that allows high volumes of water to pass through extremely tiny holes called ‘nanopores’ while blocking salt and other contaminants. The material they’re using – a nanometre-thick sheet of molybdenum disulphide (MoS2) riddled with these nanopore holes – is the most efficient of a number of thin-film membranes that the engineers modelled, filtering up to 70 percent more water than graphene.

“Even though we have a lot of water on this planet, there is very little that is drinkable,” said Narayana Aluru, a professor of mechanical science and engineering at the University of Illinois and leader of the study. “If we could find a low-cost, efficient way to purify sea water, we would be making good strides in solving the water crisis.”

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