12 April 2016

Experimental battery uses bacteria to charge and recharge

bacteria battery

Rechargeable battery technology has been improving incrementally in recent years, but we’re still working with the same heavy, dangerous, expensive materials. A group of researchers from The Netherlands has devised a new biological battery that charges and discharges with the aid of bacteria. They’ve tested this system on the small scale and managed 15 charge cycles in a row.

This “bioelectrochemical” battery consists of two parts. There’s a microbial electrical synthesis (MES) module that takes electrons and uses them to generate acetate. This is a metal salt that can be used to store electrical charge. The other side of the battery is a microbial fuel cell (utilizing various anaerobic bacteria) that processes that acetate via reduction/oxidation, resulting in the release of electrons. These are then fed into a circuit to harvest the power that was stored in the first step. More power can be added to the MES system to recharge, and the whole process starts over again.

The team tested this design by feeding power in over the course of 16 hours. It then provided power over the course of 8 hours. Does that sound like it might mesh well with any particular type of technology? Yep, it’s a great match for solar power, and indeed that’s the application the researchers have in mind. In areas that have lots of sunlight, there’s an almost unlimited supply of power during the day, but you have to store that power for use at night.

bacteria battery working

The bacterial battery described in the paper might be ideal for storing energy from solar power, but first some improvements need to be made. For one, the efficiency isn’t what we’d expect from a modern lithium-polymer battery. The team reports roughly 30-40% cycle efficiency, compared with upward of 80% in the best batteries we have now. The bacterial batteries would also need a bit more care than a lithium-ion system. If the bacteria inside were to die, the battery would stop working.

Despite these shortcomings, the study authors believe that this is an important first step. The study includes data from 15 charge cycles of the battery, and it maintained very consistent performance throughout. The self-renewing nature of bacterial colonies might mean this approach has better longevity than lithium-ion, which only works for a few hundred cycles.

With additional research, bioelectrochemical batteries may have similar capacity and efficiency compared with conventional ones, but with much lower costs and fewer volatile chemicals. Like so many other proposed battery technologies, this one is a few years off.

Source: extremetech

Ultrasound makes for palm-based computer displays you can feel

Ultrasound palm computer
Researchers at the University of Sussex are working to augment palm-based displays by adding tactile sensations to the mix.

From buzzing phones to quivering console controllers, haptic feedback has become indispensable in modern computing, and developers are already wondering how it will be felt in systems of the future. Sending ultrasound waves through the back of the hand to deliver tactile sensations to the front might sound a little far-fetched, but by achieving just that UK scientists claim to have cleared the way for computers that use our palms as advanced interactive displays.

For years now scientists have been chipping away at the idea of using human skin as a computer display. It sounds unlikely, but with technology becoming more miniaturized, the uptake in wearable devices and more time spent gazing into computer screens, in some ways it seems natural that we use our most readily available surfaces as gateways to the digital realm.

While we're not expecting the very next Fitbit to project your calories burned onto your forearm, some promising prototypes have emerged in this area. The Skinput display system from 2010 used a bio-acoustic sensing array to translate finger taps on the palm into input commands, while the Cicret wristband concept from 2014 envisioned beaming an Android interface onto the arm and used proximity sensors to follow finger movements.

Researchers at the University of Sussex are working to improve palm-based displays by adding tactile sensations to the mix. Importantly, they are aiming to do so without using vibrations or pins, approaches they say have plagued previous efforts as they require contact with the palm and therefore disrupt the display.

So they are looking to sneak in the back door. Their SkinHaptics system relies on an array of ultrasound transmitters that when applied to the back of the hand, send sensations to the palm, which can therefore be left exposed to display the screen.

The team says it was able to achieve this through something it calls time-reversal processing. As the ultrasound waves enter through the back of the hand they begin as broad pulses that actually become more targeted as they move through to the other side, landing at a specific point on the palm. The researchers liken it to water ripples working in reverse.

"Wearables are already big business and will only get bigger," says Professor Sriram Subramanian, who led the research. "But as we wear technology more, it gets smaller and we look at it less, and therefore multisensory capabilities become much more important. If you imagine you are on your bike and want to change the volume control on your smartwatch, the interaction space on the watch is very small. So companies are looking at how to extend this space to the hand of the user. What we offer people is the ability to feel their actions when they are interacting with the hand."

You can see a prototype of the SkinHaptics system demonstrated in the video below.

Source: University of Sussex, gizmag

24 March 2016

In the future, we might clean our clothes using nothing but light

silver nanoparticles in fabric

Red indicates the coverage of silver nanoparticles in a fabric in this image that's been magnified 200 times (Credit: RMIT University).

Even though we no longer have to beat our clothes on rocks to get them clean, laundry is still a pretty tedious chore. If researchers at Australia's Royal Melbourne Institute of Technology (RMIT) have their way though, the amount of time we spend measuring capfuls of liquid, scraping out the lint filter and refolding our duds may soon get slashed thanks to a new coating that cleans fabrics whenever they're exposed to light.

Imagine being able to simply hang your shirt in a lit closet to get it clean. Or taking a walk on a sunny day and arriving home with a perfectly clean shirt. Both things might be possible with RMIT's new technology that grows copper and silver-based nanostructures on fabrics.

When the tiny metallic constructs are exposed to light either from a manmade or natural source they create "hot electrons" that in turn release energy bursts that dissolve organic matter. So that grass stain you got from playing football would be blasted away, but the ink from changing the cartridges in your printer might not.

To create the self-cleaning fabric, the MIT team dipped the cloth into various solutions which caused the nanostructures to grow on the textile. It took about 30 minutes for the nanostructures to form. After that, they deliberately stained the fabric and witnessed the cleaning action take place in as little as six minutes.

The team says the technique is cheap and efficient and can easily be scaled up to an industrial scale, and it is these attributes that give it advantages over similar self-cleaning fabric technologies.

cotton coated with silver nanoparticles
This image of the cotton coated with silver nanoparticles is magnified 150,000 times

Although you won't be seeing self-cleaning clothes hitting the rack in your local shops just yet, RMIT researcher Dr Rajesh Ramanathan said that the next step for he and his team is to test the fabrics with staining agents relevant to consumers, like tomato sauce or wine.

"There's more work to do to before we can start throwing out our washing machines, but this advance lays a strong foundation for the future development of fully self-cleaning textiles," he said.

Source: RMIT University

20 March 2016

Methane explosion craters off Norwegian coast linked to fringe Bermuda Triangle theory

Norwegian coast Bermuda Triangle theory

Scientists at the Arctic University of Norway have stirred things up this week by announcing that they’ve found giant underwater craters off their coast, which they believe were formed by exploding natural gas buried in the seafloor. This is not itself controversial. What’s controversial is that the scientists suggested the phenomenon could explain the Bermuda Triangle.

The researchers described craters in the Barents Sea that are up to half a mile wide and 150 feet deep. The craters appear to have been caused by the explosive release of methane hydrate, also known as methane clathrate or natural gas, that had been deposited long ago in the sediment below.

Norwegian coast Bermuda Triangle theory

The Bermuda Triangle. Image: Wikipedia

We don’t know yet whether these methane explosions even happen in the Bermuda Triangle region. If they did, though, the scientists suggest that the violent disturbances to the water and atmosphere could buffet a ship or a plane, capsizing it or causing some other sudden calamity. While the risk to passing ships has yet to be conclusively established, though, gas hydrates are very real. We used to think methane hydrates were only found on ice planets, but more recent exploration and research have determined that we do find these crystalline deposits of methane in Earth’s ocean floors.


Methane - four hydrogen atoms connected to a single carbon atom is one of the simplest organic compounds

Methane is a colorless, odorless gas, and it’s also nonpolar normally, it behaves like oil in water, stubbornly refusing to mix or blend. But a great deal of Earth’s methane was produced by the long-ago decomposition of vast, ancient beds of plankton buried in the seafloor under the crushing pressures of the deep ocean. The sheer pressure means that molecules of methane are physically forced to mingle with water molecules hence the name, hydrate. The resultant substance is kept stable in a solid, even crystalline form by the weight of all that water. This is also why we don’t find methane clathrates in shallow seas; the pressures there aren’t enough to keep the methane solid. But with the right kind of disturbance, parts of the deep-ocean crystalline hydrate deposits can break off and even explode violently as they transition from solid to gas. Oil workers call these gas explosions “burps of death.”

There have been a number of conspiracy theories about the Bermuda Triangle, some better substantiated than others, but many experts remain unconvinced the zone even exists as an anomaly. It’s a heavily trafficked region and has been for a long time. Comparing the data shows that ships and planes disappear from the Bermuda Triangle at about the same frequency as they disappear from anywhere else, raising questions about whether the Triangle is nothing more than a collective case of confirmation bias. And the waters might not even be deep enough for the methane hydrate deposits to form in the first place. If the scientists are right, though, as climate change warms the oceans (helped along by, poetically, methane as a potent greenhouse gas), more and more of these tumultuous releases of methane will occur, making them more easily studied.

(Top Image credit: NOAA/Hurricane Joaquin, 2015)

Source: Extremetech

12 February 2016

World record Internet data transfer rate almost 50,000 times faster than broadband

Internet data transfer rate almost 50,000 times faster than broadband

Using advanced digital signal processing techniques, researchers have created an optical data transmission system able to transfer information at a rate of 1.125 terabytes per second (Credit: Shutterstock)

At a blistering 1.125 terabytes per second, a new optical communication system developed by University College London (UCL) researchers has created a new record for the fastest ever data transfer rate for digital information. At the quoted rate, say the researchers, the entire HD series of the TV show Game of Thrones could be downloaded in less than one second.

To help achieve these incredibly fast transfer rates, the researchers took recent developments from the realm of information theory in regard to the maximum amount of information that can be transmitted being limited by the finite signal-to-noise ratio (SNR), and applied advanced digital signal processing techniques to optimize the SNR and maximize data throughput.

In other words, the team determined the most efficient way to encode data in optical signals, taking into account the limitations of the transmitter and receiver. They then cleverly used noise reduction techniques normally found in wireless communications and applied them to optical transmission. In this way, the team was able to ensure that the transmitted signals were able to be minimally effected by distortions in the system electronics.

"While current state-of-the-art commercial optical transmission systems are capable of receiving single channel data rates of up to 100 gigabits per second, we are working with sophisticated equipment in our lab to design the next generation core networking and communications systems that can handle data signals at rates in excess of 1 terabit per second," said Lead researcher, Dr Robert Maher, of UCL Electronic & Electrical Engineering. "For comparison this is almost 50,000 times greater than the average speed of a UK broadband connection of 24 megabits per second, which is the current speed defining "superfast" broadband."

Building on previous work, where the team transmitted optical signals over a world-record 5,890 km (3,660 mi) error-free, the new system employs a total of fifteen separate data transmission channels, with each carrying an encoded optical signal of different wavelengths. Modulated using the 256QAM format normally employed in cable modems, the 15 signals were combined and then sent to a single optical receiver for detection. In this way, by arraying the transmission channels, the researchers created a "super-channel" that they believe may form the basis for future high-capacity communication systems.

"Using high-bandwidth super-receivers enables us to receive an entire super-channel in one go," said Dr Maher. "Super-channels are becoming increasingly important for core optical communications systems, which transfer bulk data flows between large cities, countries or even continents. However, using a single receiver varies the levels of performance of each optical sub-channel so we had to finely optimize both the modulation format and code rate for each optical channel individually to maximize the net information data rate. This ultimately resulted in us achieving the greatest information rate ever recorded using a single receiver."

Though initial research has been conducted with the transmitter feeding directly to the receiver in order to realize the maximum data transfer rate, the team now intends to run the system with long cable lengths. In this way, performance tests will be conducted to measure the achievable data rates over long distances where distortion is introduced by the optical cables themselves.

The results of this research were recently published in the Nature journal Scientific Reports.

Source: University College London, gizmag

11 February 2016

Mechanical chameleon blends with color backgrounds

Mechanical Chameleon through Dynamic Real-Time Plasmonic Tuning

Mechanical Chameleon through Dynamic Real-Time Plasmonic Tuning. Credit: ACS Nano (2016). DOI: 10.1021/acsnano.5b07472

Name one intense research area and you will not go wrong in choosing camouflage. ACS Nano has published "Mechanical Chameleon through Dynamic Real-Time Plasmonic Tuning."

The paper will interest those who recognize the challenges ahead in improving ways of hiding and ways of blending in with the environment.

The authors are from China and Georgia Institute of Technology (Atlanta, Georgia).

As they said in their paper, "Optical invisibility represents one of the greatest challenges in military and biomimetic research." From the earlier days of pattern painting and on toward approaches for the invisibility cloak, explorations continue.
These researchers are on a path which permits real-time light manipulation readily match-able to the color setting in an environment.

A video on their work shows the chameleon rolling past three colors and changing its color accordingly. The "chameleon" actually is a 3D-printed model covered in plasmonic displays.

The authors discussed what they had fabricated: "a biomimetic mechanical chameleon and an active matrix display with dynamic color rendering covering almost the entire visible region."

Adam Westlake in SlashGear found their work impressive enough. "The future of color-changing body armor may be here," he said, in the form of this chameleon-shaped robot.

Mechanical Chameleon through Dynamic Real-Time Plasmonic Tuning. Credit: ACS Nano (2016). DOI: 10.1021/acsnano.5b07472

They summarized what they accomplished, saying "we have achieved reversible full-color plasmonic cells/display by electrochemically controlling the structure of a Au/Ag core–shell nanodome array and successfully integrated these cells onto a mechanical chameleon, which can blend automatically with colored backgrounds."

Westlake said the plasmonic displays can produce colors and rapidly change between them by detecting the background with light sensors and he wrote about their approach:

Displays are made from small sheets of glass with a grid of holes measuring 50 nanometers wide. The team coated the sheets in gold, creating small domes in each hole, followed by another layer electrolyte gel with silver ions.

"Plasmons, or ripples of electrons, are said to be created when light hits the gold domes, which in turn determines its properties of reflection and absorption," wrote Westlake. "Different colors are produced when an electric field is connected, altering how many silver ions stick to the gold. Sensors were then added that can detect the light and color of the surroundings, and then adjust the electric field to change colors as needed."

The authors said their mechanical chameleon can perform against backgrounds with only three primary colors (red, green, and blue). At the same time, though, they said their technology can also interface with a complex environment and provide a new approach for artificial active camouflage.

"This application is readily approachable by using more technically advanced autonomous systems, which can be addressed by using a highly integrated machine vision system that can capture and simulate the entire color patterns of the environment and then drive the color-changing process in individual cells, fully merging the mechanical chameleon with the surroundings."

More information: Guoping Wang et al. Mechanical Chameleon through Dynamic Real-Time Plasmonic Tuning, ACS Nano (2016). DOI: 10.1021/acsnano.5b07472

The development of camouflage methods, often through a general resemblance to the background, has recently become a subject of intense research. However, an artificial, active camouflage that provides fast response to color change in the full-visible range for rapid background matching remains a daunting challenge. To this end, we report a method, based on the combination of bimetallic nanodot arrays and electrochemical bias, to allow for plasmonic modulation. Importantly, our approach permits real-time light manipulation readily matchable to the color setting in a given environment. We utilize this capability to fabricate a biomimetic mechanical chameleon and an active matrix display with dynamic color rendering covering almost the entire visible region.

source: Tech Xplore

The wistful sigh is really a survival mechanism

sighing reflex
A fluorescent-green marker on each side of the brain stem illuminates the two networks of 200 neurons that control the sighing reflex (Credit: Krasnow lab/Stanford)

A sigh may do more for your health than provide emotional relief. Researchers in California claim to have identified the source of the sigh in the brain, which they say is a life-sustaining reflex for healthy lung functioning. Humans sigh around 12 times per hour to reinflate the half-billion or so tiny, balloon-like sacs in the lungs called alveoli, which are vital in regulating the flow of oxygen and carbon dioxide. A sigh is mostly an involuntary deep breath, or a regular breath with another added on top before an exhale.

According to the study conducted by researchers from UCLA and Stanford University, sighs are a response to the lungs' signal to inflate the alveoli, and originate from two tiny clusters of 200 neurons in the brain stem – the area also responsible for autonomic functions such as heart rate, breathing and sleeping. The researchers believe the sigh has the fewest number of neurons linked to any basic human behavior. The findings also provide insights into mechanisms that may be behind other complex behaviors.

Mark Krasnow, one of the study's authors and a biochemist at Stanford University School of Medicine, said the brain's breathing center controls the rate of breath, as well as the type of breath taken. "It's made up of small numbers of different kinds of neurons," he said. "Each functions like a button that turns on a different type of breath. One button programs regular breaths, another sighs, and the others could be for yawns, sniffs, coughs and maybe even laughs and cries."

Using laboratory mice, which sigh up to 40 times per hour, the researchers looked at 19,000 patterns found in mice brain cells with possible links to genetic activity. From this they found 200 neurons in the brain stem that produce and release one of two neuropeptides, which facilitate communication between brain cells.

While the researchers were unclear on which brain cells the neurons were talking to or why, they knew the strain of peptides was also found in humans and very active in the area of the brain involved with sighing. By blocking one of the peptides in the mice, their rate of sighing was reduced by half, and shut down completely when blocking both peptides.

"These molecular pathways are critical regulators of sighing, and define the core of a sigh-control circuit," said Krasnow. "It may now be possible to find drugs that target these pathways to control sighing."

Without sighing, our lungs would eventually fail. Early breathing devices did not provide regular deep breaths to patients, who sometimes died as a result. Today's ventilators compensate for sighs by delivering a large volume of air.

The study was published in the online edition of the journal Nature.

Source: UCLA Health, gizmag 

08 February 2016

LAVA P7 an entry level smartphone in India!

While there’s no dearth in Indian gadgets market with new launches of power packed smartphones that come at heavy price tags, there still needs to be a revolution in the entry level smartphones. Not everyone desires phones to be loaded with complex features as they are hardly useful for them. That minority wants their smartphone to be equipped with basic advanced features. One such phone which has been launched recently for this segment is Lava P7. Coming at a price tag of Rs.5,499; Lava P7 will be available both offline and online.Lava has previously also released entry level smartphones.Here’s what you need to know about it:

1) Design and display

The Lava P7 smartphone has a 5.0 inch display screen with a resolution of 854x480 pixels. The screen size is apt for people who like a big sized screen and don’t want to spend a fortune for possessing it. The resolution might not be the best (Read: HD!) but it looks decent enough for the attractive price tag the smartphone comes at. It’s available in three colors i.e. White, Gold and Blue.

2) Performance

At the budget friendly price it comes at, Lava P7 seems to offer a pretty good performance. It is powered by 32bit quad-core MediaTek processor clocked at 1.2GHz. Coupled with 1GB RAM, the specs do not sound mediocre at all. A smartphone running on 1.2Ghz processor is ideal for playing heavy games associated with modern graphics, image/video processing and working with different apps simultaneously. The smartphone will be available online in a matter of just few days. Don’t forget to avail Flipkart coupons present on CashKaro to earn reward points on your purchase.

3) Camera

Camera quality is one aspect which many people aren’t ready to overlook. Keeping this consideration in mind, Lava made sure that it was offering a features rich camera even in an entry level smartphone. Lava P7 features a 5 mega pixel camera and a 2 mega pixel front camera with LED flash. The LED flash will ensure that you capture clear and bright selfies. The camera is also backed up by features like Face beauty, Live photo and Voice capture. The voice capture feature will make it easy for you to take selfies with its command.

4) Storage and battery

Long-lasting battery is one thing which you can’t find even with the high-end smartphones, leave this entry level smartphone. Lava P7 3G smartphone comes with a 2000 mAh battery. It claims to offer up to 20 hours of talk time. The handset also offers a power saving mode to give you extra juice.If you use your phone excessively throughout the day, it is better that you invest in a power bank. A power bank will keep your battery woes at bay. You wouldn’t be required to worry unnecessarily about holding a dead battery phone at the end of the day. Regarding storage, it can be expanded up to 8GB. To get this smartphone at the best deal, avail Snapdeal coupons via CashKaroand get access to fabulous offers.

5) Child mode feature and connectivity options

The smartphone is coupled by an interesting feature calledChild mode which assists using certain sounds that help in gaining the attention of kids and making tricky clicks easy. That’s awesome, right? There are other useful features also like smart wake-up, multipoint touch, custom and drawing features. The smartphone supports Wi-Fi, Bluetooth and GPS.

The smartphone runs Android 5.1 Lollipopbut the company promises that the device will upgrade to Android 6.0 Marshmallow.

07 February 2016

Canonical trumpets Ubuntu tablet's convergence features

How about that, a tablet running Ubuntu? A new tablet is scheduled to go on sale this year. Canonical announced the launch in a news release datelined London on Thursday. The tablet goes by the name Aquaris M10 Ubuntu Edition, shipping with the latest Ubuntu software.

What's so special about this one? The key promotional word is "convergence," Ubuntu-style. The company said the table is capable of "providing both a true tablet experience and the full Ubuntu desktop experience."

Users can expect to make use of a range of desktop applications, desktop notifications, communication from the desktop interface using the phone's telephony and messaging application and thin client support for mobility. Capabilities include file browsing, file and folder creation and management.

Namely, you can let your tablet double as a PC: You connect a Bluetooth mouse and keyboard to convert the Aquaris M10 Ubuntu Edition into a full Ubuntu PC and also "connect the tablet to an external display for a full-sized PC experience."

The tablet-PC interplay did not escape notice on Thursday by Eric Brown in Linux.com. "If you plug in a Bluetooth dongle for a keyboard and mouse, Ubuntu immediately recognizes the new input methods, and if you connect the tablet to a larger display, Ubuntu immediately scales to the larger screen. With a larger display, a 'side stage' feature kicks in that presents multiple open windows for different applications, as well as multi-column text options."

Chris Velazco in Engadget also made note of the interplay once peripherals are connected, "Ubuntu's touch-friendly interface shifts into a more familiar desktop view, allowing you to multitask, run desktop apps and manage mobile apps you already have installed."

Ubuntu as an operating system has a good reputation and CNET's Richard Trenholm, a senior editor, offered some background to the tablet launch news: " Ubuntu is a long-established open-source operating system originally for computers, beloved among developers and tinkerers looking for an alternative to Windows or Macs. But in recent years, Canonical, the British company behind Ubuntu, has expanded the operating system so it works in other devices, from phones to drones. The unique selling point is that the same software underpins phones, tablets and computers."

Two points that will attract buyers are that (1) it is Ubuntu, as stated and (2) one is getting a tablet that also works like a laptop and a desktop. The announcement said, "Ubuntu is now the only platform that runs both a mobile-based full touch interface and a true PC experience from a single smart device."

This Ubuntu environment may also be seen as offering good security for enterprise buyers. The announcement said, "Excellent security comes as standard as part of the Ubuntu OS but Ubuntu convergence brings unparalleled enterprise-grade, system-based security. For many organizations wanting to take tight control over their own systems, avoiding third party access, Ubuntu is ideal." Canonical said it will be on sale online from Q2 2016.

The Aquaris M10 Ubuntu Edition tablet has a 10.1 inch screen. The screen is protected by Asahi Dragontrail glass, said CNET. It has 8.2 mm of thickness and 470 grams in weight.

Eric Brown in Linux.com stated in a few words what highlights the significance of the launch: "It's not a stretch, then, to say the Aquaris M10 is the first real Ubuntu tablet."

Velazco nonetheless found it "a little surprising that it took this long for a full-blown Ubuntu tablet to hit the market, but better late than never, we guess."

Brown offered more details. The Aquaris M10 is equipped with a 64-bit, quad-core, Cortex-A53 MediaTek MT8163A system-on-chip clocked to 1.5GHz and high-powered ARM Mali-T720 MP2 GPU. He said the product ships with 2GB of RAM, 16GB flash, and microSD slot.

Price? The news release did not state the price.
Source: Tech Xplore

Paper waste converted into eco-friendly aerogel

There's aerogel in that thar paper (Credit: Shutterstock)

Known as "frozen smoke" because of their milky translucent appearance, aerogels are among the world's lightest solid materials. Consisting of 99.8 percent air, they're highly heat-resistant and are an excellent form of insulation. Now, scientists at the National University of Singapore (NUS) have used paper waste to create one.

Previously, aerogels have been made mainly from silica, along with substances such as metal oxides, polymers, carbon nanotubes and graphene. The NUS technique is claimed to be considerably more environmentally-friendly, however, using less power, releasing less toxic emissions, and requiring less hazardous chemicals plus it uses a material that might otherwise go into the landfill.

Assistant Professor Duong Hai Minh (right) holds a sample of the cellulose aerogel which he developed with his team members, Gu Bowen (centre) and Siah Jie Yang (left) who are both undergraduate students from the Department of Mechanical Engineering

The "cost-effective" production process begins by mixing water with cellulose fibers, the latter obtained by mulching the paper. A cross-linking polymer resin is then added to the mixture, after which it's sonicated sonication is the process of using sound energy to agitate particles in a solution.

Next, the mixture is poured into molds and frozen at -18º C (0º F) for 24 hours, after which it's freeze-dried at -98º C (-144º F) for two days. Finally, it's cured in an oven at 120º C (248º F) for three hours. The final result is an opaque biodegradable material that is non-toxic, flexible, mechanically-strong and oil-absorbent.

When coated in methyltrimethoxysilane (MTMS), the cellulose aerogel becomes very hydrophobic (water-repelling). This means that if it were placed in an oil spill, it could soak up as much as 90 times its dry weight in crude oil, without "filling up" on water. It could then be wrung out like a sponge, allowing over 99 percent of the absorbed oil to be recovered.

The material could also find use as wall insulation in buildings. Besides keeping heat contained within the structure, it would resist moisture buildup, add strength to the walls, and take up less space than traditional materials such as fiberglass wool. It might likewise be used as a form of protective packaging, or in wound-plugging medical sponges. When doped with metallic nanoparticles and hammered flat to remove its air content, the aerogel can additionally be converted into a mechanically-strong thin magnetic film.

If not coated in MTMS, the highly-porous aerogel does absorb water and other liquids, allowing for its use in products such as diapers or sanitary napkins.

The technology is being commercialized by materials company Bronxculture.

Source: NSU, gizmag
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