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Science & Technology News (468)

Making Anti-Glare and Anti-Reflective Displays

Category: Science & Technology
Posted: July 24, 2014 01:53PM
Author: Guest_Jim_*

Anyone who has tried to look at a phone, tablet, or laptop screen in Sunlight knows just how frustrating the glare and reflections of the screen can be. This makes it rather unsurprising that so many products exist to counter the problems, but some do not work well with glass. Researchers at the Institute of Photonic Sciences and Corning Incorporated though have developed a new method to make glass surfaces anti-glare, anti-reflective, and even hydrophobic.

Today you can go out and get anti-glare filters and films for your devices, and some have nanostructures on top of them, to add anti-reflective properties. These structures do not work well on glass, so the researchers worked on the glass directly. By roughening the surface of glass at a very fine scale, it can be made anti-glare without sacrificing transparency. Etching in nano-sized teeth makes it anti-reflective, and as it turns out, the resulting surface features made the glass water repellent, like a lotus leaf.

This method to affect the properties of the glass is inexpensive and can be scaled up for industry use. Before that will happen though, more research needs to be done, in part to determine how well the features endure touchscreen use.

Source: American Chemical Society



Encoding Optical Information at Sub-Wavelength Scale

Category: Science & Technology
Posted: July 24, 2014 05:57AM
Author: Guest_Jim_*

Information can be stored in many ways, and for many systems the density it is stored at is very important. There can be limits to the density though, such as with the wavelength of light. By using a plasmonic film though, researchers at the University of Illinois have recorded optical information at sub-wavelength scale, and in real time.

The plasmonic film is actually an array of gold, pillar-bowtie nanoantennas (pBNAs) that reacts to laser light. The reaction is analogous to how photographic film behaves when exposed to light, but the effect occurs in real time, and does more than store an image. When exposed to laser light, the pBNAs actually create optofluidic channels without walls, allowing the researchers to affect the trajectory of particles in a solution. Other optofluidic systems have been made that achieve the same goal, but do have physical walls.

When the researchers tested it, the bit size was around 425 nm, which is directly related to the spacing of the antennas. If this were applied to an optical disc that would be around 28.6 GB of data, but by modifying the spacing of the array and the antennas, it could be scaled up to 75 GB a disk. That is of course only considering data storage applications, but this discovery could have many other photonic uses.

 

 

Source: University of Illinois, College of Engineering



Decreasing Queue Length in Data Centers

Category: Science & Technology
Posted: July 18, 2014 06:06AM
Author: Guest_Jim_*

Most every time you visit a website, a host of servers somewhere have to run the right operations to gather the data you need, and then send it to you. As some websites use large data centers, with the servers working for you spread out, the latency between the servers can impact performance. Currently decentralized communication protocols are used to manage communication in a data center, but researchers at MIT have recently designed a new, centralized system that can offer better performance.

Decentralized protocols enable each node in a network to send and receive information without instruction. Provided the routers transmitting the information do not get overwhelmed, this approach can work well, but in some data centers they are being overwhelmed, causing large queues to form, leading to congestion. One would not expect a solution to come from sending requests to a central arbiter server, which takes 40 microseconds, but the MIT, Fastpass system not only reduces the congestion, but does so by a very significant amount. The Fastpass system takes advantage of parallel programming to divide the work of scheduling communication across multiple cores. The first core looks at the pending requests, schedules one for a slot, and then passes to the next core all of the requests involving either the source or destination node of the schedule request.

The researchers found that by using this approach, the Fastpass system is able to handle a network transmitting at 2.2 terabits per second, with just eight cores. In experiments to be presented in August, the researchers will show that Fastpass cut the average queue length in a Facebook data center by 99.6%, and the average latency from 3.56 microseconds to 0.23 microseconds.

Source: MIT



Improving Photoresist for Chip Manufacture

Category: Science & Technology
Posted: July 17, 2014 03:12PM
Author: Guest_Jim_*

According to Moore's Law, the number of transistors that can fit on a microprocessor will double roughly every two years. While it has been holding true for some time now, the technology has rapidly been approaching a barrier that could bring everything to a halt. One part of the barrier has been the photoresist used to etch circuitry onto silicon, but now a partnership between Berkeley Lab and Intel has found what could be its replacement.

To create the small and intricate circuitry in computer chips, manufacturers start with a wafer of silicon and coat it with a photoresist. Using a UV light source, an image of the circuitry is burned onto the photoresist, changing its properties where the light hits. A solvent is then used to wash away the unwanted photoresist, enabling selective deposition to build the circuitry up. The photoresist currently used was first developed to work with deep UV light, which has wavelengths between 248 and 193 nm, but manufacturers want to transition to using extreme UV, which can reach down to 13.5 nm for its wavelength. Due to the complexity of the photoresist compound, many have avoided developing a replacement as the risk could be so great.

A new photoresist is going to be needed to reach the smaller sizes chip makers want though, and some work has been done to that end. The Berkeley researchers decided to combine two promising photoresists and were surprised to find the mixture actually keeps the properties of its parts. One photoresist had great stability, but took long exposure times to achieve it, while the other was highly sensitive, but less mechanically stable. More work needs to be done to optimize the mixture, but the researchers believe it could reach manufacturing lines by 2017.

Source: Berkeley Lab



Producing Electricity through Condensation

Category: Science & Technology
Posted: July 17, 2014 06:54AM
Author: Guest_Jim_*

Many interesting scientific discoveries have come from unexpected sources. Last year it was discovered at MIT that when water droplets leap from a superhydrophobic material, they can gain an electrical charge. Now MIT researchers have found a way to use this phenomenon to produce useable electricity.

Superhydrophobic materials are characterized by the fact that water hates to touch them, which has made them interesting for use in condensers. Water will still condense onto the hydrophobic material, and by leaping off of it, frees up space for more water to condense. When the researchers found that these leaping droplets will be charged, they added oppositely charged plates to condensers, to improve efficiency. By making the plate superhydrophilic instead, and connecting it to the superhydrophobic plate, the MIT researchers found they had created an electrical circuit.

So far tests have only produced 15 picowatts of power per square centimeter, but the researchers believe the device could be easily tuned to 1 microwatt per square centimeter, which is comparable to other devices that harvest ambient energy. While that is not much power, the remote systems that would be powered by this technology, do not necessarily need much.

Source: MIT



First Photonic Router Created

Category: Science & Technology
Posted: July 16, 2014 02:04PM
Author: Guest_Jim_*

The ability to controllably route information is fundamental to electronic computers, and is similarly necessary for future quantum computers. Researchers at the Weizmann Institute of Science have recently created the world's first photonic router, capable of routing photons based on photonic signals.

The router works by switching the state of an atom caught in a trap. In one state, the atom will allow photons coming from the right to pass on, but will reflect photons coming from the left. When it reflects a photon though, its state will flip and now photons from the left will pass on while photons from the right are reflected, and trigger another switch. The photons from the right and left are coming from optical fibers, which have been coupled to ultra-high quality, miniature optical resonators.

As photons are capable of carrying quantum information and relatively protected from interactions that would destroy the information, this system could prove invaluable for quantum computers. Next the researchers want to work on other kinds of devices, such as quantum memory or logic gates, and see if they too can be made to function only with photons.

Source: Weizmann Institute of Science



IGN Turns to University Startup to Increase Video Views

Category: Science & Technology
Posted: July 16, 2014 06:07AM
Author: Guest_Jim_*

For any website with video content, views are critical for not only sharing the content but generating ad revenue. Obviously the videos must be interesting, but so too must their thumbnails, to encourage people to click and watch. Neon Labs, a Carnegie Mellon University startup company has recently signed an agreement with IGN Entertainment, so the startup's thumbnail-selection software can find the best images.

Researchers from many institutions have found that our preferences can be influenced by visual perception, without our knowing. The Neon Labs software applies this knowledge to scan a video stream for the thumbnail that will encourage the most engagement. In some cases the algorithms can lead to 100% more engagement over the images humans may select. For IGN though, the clickability increased by 30%, on average, which is still impressive. It also took over the significant amount of work required to select thumbnails, making it a "huge win" for the company.

Source: Carnegie Mellon University



Generating Spin Current with Heat

Category: Science & Technology
Posted: July 15, 2014 02:00PM
Author: Guest_Jim_*

For decades we have been using electronics that operate on the charge of electrons, and while the technology has been serving us very well, it is approaching its limits. A potential replacement is spintronics, which utilize another property of electrons known as spin and spin current. Among the many benefits of spintronics is the possibility of great speed, and now researchers at the University of Illinois have found a way to create spin currents at that great speed.

A normal electrical current, like those used in electronics, is made of electrons with spins pointing in random directions. A spin current is formed when those spins line up, but causing that to happen is not easy. Normally it requires creating a voltage difference across a structure, but the Illinois researchers were able to produce a current using heat instead. Within a metallic ferromagnet are three energy reservoirs, and by creating a temperature difference between two of them, the researchers were able to generate a spin current. The two reservoirs are electrons and magnons, and the temperature difference caused the spin angular momentum of the magnons to be transported to the electrons.

Unlike the more traditional means of producing a spin current, this thermally-driven method created the current in trillionths of a second, or picoseconds. Naturally this great speed would be very welcome for fast magnetic memory devices.

Source: University of Illinois



Using Spin Current to Write Data

Category: Science & Technology
Posted: July 15, 2014 06:54AM
Author: Guest_Jim_*

Though flash-based SSDs may be replacing magnetic hard drives in many of our machines, the traditional HDD is still a common piece of computer hardware. The technology is approaching a limit however, as bits can only be so small before writing one bit risks disrupting those around it. Researchers at Eindhoven University of Technology have developed a more efficient way of writing magnetic bits though, that could increase speeds tremendously.

Typically flipping a bit requires a local magnetic field, causing the magnetic properties of the hard disk material to change from one state to another. The two states can be read as either zero or one, for binary data. Instead of using a magnetic field though, the Eindhoven researchers use ultrafast lasers to trigger a spin current. Spin is an intrinsic property of many particles, including electrons, and its direction determines the direction of the particle's magnetic field. A spin current is just a flow of electrons all with the same spin. To produce the current, the researchers fired ultrafast laser pulses at a material made of two magnetic layers, with a neutral layer in between. When the laser strikes the top layer, the electrons in it try to move through the material, and take with them the spin of the top later. This spin then exerts a force on the bottom layer, causing it to flip its magnetic state.

The changes in magnetic state of the bottom layer take around 100 femtoseconds, which is approximately 1000 times faster than modern technology can achieve. While that is definitely impressive for write speeds, because of the use of lasers, this technology could also be used in future optical computers, for data storage.

Source: Eindhoven University of Technology



Potential Replacement for Flash Memory Gets a Boost

Category: Science & Technology
Posted: July 14, 2014 02:04PM
Author: Guest_Jim_*

Flash memory has impacted many people and technologies, thanks to its speed, stability, and density. While it may be a champion memory technology at the moment, there are new technologies looking to supplant it. Among these is Resistive Random Access Memory (RRAM), which researchers at Rice University have recently made more appealing to the industry.

This new memory type works by putting a resistive material between two wires. When a great enough voltage is applied to the wires, the electricity will form a conducting path through the normally resisting material. Those pathways do not need to be permanent though, allowing RRAM to be rewriteable, and because of how small its cells can be, it can have 50 times the data density of flash. Though many materials can be used for RRAM, the Rice researchers are working with silicon dioxide, which is already a very well understood material, and one with many advantages over its competitors. These include the ability to be manufactured at room temperature, a high on-off ratio, low power consumption, and nine-bit capacity per cell. The recent research has increased silicon dioxide's potential by revealing that porous silicon dioxide requires thirteen times less energy to create pathways in and does not require special edge fabrication methods.

Some predict that RRAM could start coming to market and competing with flash in a few years, thanks to its greater speed and density. Now that it has been shown that a device edge structure is not needed, companies have already started trying to license the technology.

Source: Rice University



Explaining the Mystery of Mercury's Origin

Category: Science & Technology
Posted: July 14, 2014 06:53AM
Author: Guest_Jim_*

For probably as long as humans have been able to look up and see other planets, we have been wondering how the planets came to be. For Venus and Earth it is generally accepted that they formed as the result of smaller objects colliding and coalescing into the planets we know today, but what about Mercury? The nearest planet to the Sun has some curious properties to it, including a very high concentration of iron, and now researchers at Arizona State University have an explanation for why.

Of the terrestrial planets in the Solar System, Mercury has the greatest concentration of metallic iron, with 65% of its mass being its iron core, compared to Earth's core making up 32% of its total mass. Also Mercury has a great many volatiles on it, such as water, lead, and sulfur, even compared to the Moon. This is particularly confusing as it indicates that the planet likely did not suffer a giant impact in the past, even though such an event would explain its lack of a mantle. The Arizona researchers though suggest that while Mercury never suffered a giant impact, like Earth and Venus did, it likely suffered many smaller, glancing impacts, which stripped off its core little by little.

The idea of glancing impacts is not new, but had always been discounted before, as the belief was that the object would be caught gravitationally, and ultimate be devoured by the larger body; proto-Venus or proto-Earth. According to the new theory and model though, glancing blows do not necessarily doom a body, and multiple could actually help preserve the dominate survivor of these impacts.

Source: Arizona State University



The Brain May Have Standard Emotional Codes

Category: Science & Technology
Posted: July 11, 2014 06:01AM
Author: Guest_Jim_*

According to some examples of science fiction, one day we will have the ability to read minds through technology, for better or worse. According to researchers at Cornell University, at least emotions may not be as hard to read as we thought. Analysis has revealed what appears to be the existence of a standard code for processing emotions.

Traditionally it has been believed that the brain processes emotions in certain regions, and that a positive or negative emotion depends on the region. This new research indicates a very different process that does partially rely on sensory experience. Subjects were presented with pictures and tastes while undergoing functional neuroimaging. The imaging revealed that the brain generates special, sensory-dependent codes in the appropriate regions for the senses, and in the orbitofrontal cortices. This indicates that the emotional experience is not limited to certain brain regions and may even by linked to perception.

The subjects were also asked to score their emotional responses to what was presented to them. The researchers found that those who reported similar scores also had similar activity patterns in the orbitofrontal cortices, which suggests that the code used there for experiences of pleasure and displeasure, may be shared across people.

Source: Cornell University



Gecko Feet do Not Permanently Adhere

Category: Science & Technology
Posted: July 10, 2014 03:08PM
Author: Guest_Jim_*

Adhesives are very useful tools, whether we are putting paintings or electronics on a surface, but sometimes we do not want to leave a residue behind or want to remove the object later. One possible solution is to apply the physics that allow geckos to walk upside-down on seemingly smooth surfaces. Researchers at Linköping University however have found that the physics involved are not permanent, and so may not be the best choice for all applications.

All molecules and atoms are attracted to each other by van der Waals forces. These are weak forces though, so you cannot expect to climb a wall just by pressing your hands against it. Geckos and spiders however have evolved special hairs that are able to get so close to a surface and with enough surface area that the van der Waals forces are able to resist gravity. The Linköping researchers decided to look into this more deeply and found that van der Waals forces do not hold indefinitely. Both the surface and the object suffer very small vibrations from molecules moving, and for the most part these are insignificant. Eventually though, these movements will fall in sync between the object and surface, which will cause them to detach from each other.

As the researchers point out, this is not a problem for geckos and other living, moving objects, but would mean you would not want to hang up anything relying on van der Waals for too long.

Source: Linköping University



New Approach to Improve Traffic Light Timings

Category: Science & Technology
Posted: July 10, 2014 07:11AM
Author: Guest_Jim_*

Nobody enjoys sitting at red lights, waiting for the signal to change, but finding the optimal timing is difficult and complex. Models do exist that can achieve amazing resolution, but these come at the cost of efficiency and sometimes larger accuracy. Researchers at MIT though are proposing a new method that could optimize timings better than these models, cutting down on wait times significantly.

Typically cities will time their traffic lights by focusing on the primary arteries and just optimizing the times along those routes. This approach has the limitation of not considering the ripple effects on other roads, such as from drivers taking an alternate route, to avoid lights. As these models will consider individual driver behavior, it becomes prohibitively complex to grow them to consider all of these effects. The MIT researchers however found an efficient way to arrive at the optimal timings while avoiding the complexity. It starts with the high resolution technique to propose timings and then uses a lower resolution model to look at traffic flow.

To test this new approach, the researchers considered the traffic of Lausanne, Switzerland. The timings it produced resulted in a 22% reduction in average wait time for the city, according to simulations. Next the researchers want to expand the model to be able to adapt to changing traffic conditions.

Source: MIT



Building Better Batteries with Sand

Category: Science & Technology
Posted: July 9, 2014 03:09PM
Author: Guest_Jim_*

Many technologies depend on others in order to operate and advance. What may be the best example of such a supporting technology is the battery, and without some new discoveries, it may be limiting future mobile devices. Researchers at the University of California, Riverside though have developed a new means to produce anodes for lithium ion batteries cheaply, while still improving performance.

Traditionally lithium ion batteries have used graphite anodes, as the carbon material has the needed electrical properties and resilience. Silicon would be a better material for its electrical properties, but it is hard to produce in large quantities and is less resilient. The Riverside researchers had a new idea for producing silicon anodes after one of them looked at a handful of beach sand. Silicon dioxide, or quartz, is a primary component of many sands, and the researchers realized that it could be purified to pure silicon by heating it with salt and magnesium. This process of removing the oxygen produces very porous silicon nanoparticles, and that porosity is valuable for battery anodes, by increasing the surface area that electrons can access.

Thanks to the nano-silicon’s porosity, batteries built using it as the anode could have triple the lifespan, or better, than conventional batteries. So far the researchers have produced coin-sized batteries, but are trying to move to larger sizes, likes those in cellphones.

Source: University of California, Riverside



Turning to Anticrystals to Better Understand Materials

Category: Science & Technology
Posted: July 9, 2014 06:12AM
Author: Guest_Jim_*

For many experiments and studies, scientists will consider ideal conditions to keep things simple. As reality is not ideal, sometimes adaptations will be made to the research to approach reality, and make the results more informative. Researchers at the University of Pennsylvania however are suggesting that for many materials, instead of starting with a perfect crystal and adding defects, it would be better to start with an anticrystal, and add order.

Crystals are materials with well-ordered internal structures, whereas anticrystals are the opposite and are completely disordered. Realistic materials would be on the spectrum between these two extremes, and everything has many properties determined by their internal structures. According to the Pennsylvania researchers, many materials would be better described from the starting point of anticrystals with added order, than perfect crystals with added disorder. The researchers liken it to a deck of cards shuffled once being closer to a totally shuffled deck, than a totally ordered one.

As many properties of materials are determined by their structures, this research could have many great impacts, including leading to better plastics, glasses, and metal alloys. For example, shrinking the crystalline patterns of steel makes the alloy stronger, and this makes the anticrystal a better starting point for describing it.

Source: University of Pennsylvania



Quantum Effect Successfully Tuned in Bilayer Graphene

Category: Science & Technology
Posted: July 8, 2014 02:02PM
Author: Guest_Jim_*

Graphene is a wonder material for many reasons, including its fantastic electrical properties and great strength. It is also special for being a high quality crystal, which can have implications for quantum mechanics. Researchers at Columbia University have recently discovered a means to tune a quantum mechanical phenomenon in bilayer graphene, which could enable it to be used in quantum computers.

The fractional quantum Hall effect involves many electrons being made to act like a single system when confined to a thin sheet and exposed to a large magnetic field. As graphene is an atom-thick sheet of carbon, it is a perfect fit for studying the effect, and it has been. This new research looks to bilayer graphene, which has some differing behaviors from single-layer graphene, such as developing a bandgap when exposed to a strong magnetic field, disrupting the electrodes ability to tune the charge density. It took some time, but the Columbia researchers eventually found a new design for the graphene system that allowed them to isolate the electrodes from the needed magnetic fields.

Now with the ability to control the charge density on the separate graphene sheets, the researchers can create the fractional quantum Hall effect in bilayer graphene, which could allow for non-abelian states to be created. These states could be used for quantum computation, but not before the researchers better understand what is happening to the electrons, as the system is so complex they are not entirely sure what is occurring.

Source: EurekAlert!



Making Graphene Ribbons Semiconducting

Category: Science & Technology
Posted: July 8, 2014 06:59AM
Author: Guest_Jim_*

Since its discovery, researchers have been working to find a way to make use of graphene in our electronics. This has been difficult though, as graphene is an electrical conductor and not a semiconductor, like silicon. Researchers at the University of Wisconsin, Milwaukee however have found that graphene nano-ribbons can become semiconductors, just by making them the right width.

Graphene is an atom-thick sheet of carbon and often worked with as a sheet, but other geometries can have special properties. As it turns out, nano-ribbons of graphene, which are typically conductors like larger sheets, can become semiconductors if they are three nanometers wide, or less. At such a small width, the electrons on one edge are able to interact with the atoms on the other, resulting in the sought-after semiconductor behavior.

Cutting the nano-ribbons that narrow is not easy though, especially as the edges have to possess the proper alignment. The researchers accomplished this with iron nanoparticles that catalyze a reaction between carbon and hydrogen atoms. Now the researchers are investigating other ways to change the properties of the nano-ribbons, by adding other atoms, such as oxygen to the edges, potentially making them act as a metal.

Source: EurekAlert!



Nonlinear Meta-Mirror Created

Category: Science & Technology
Posted: July 7, 2014 02:21PM
Author: Guest_Jim_*

An important and useful property for many optical systems is linearity. Essentially it is why light passing through glass is the same when it exits as when it enters the material. Nonlinear materials however can change light waves, and researchers at the University of Texas at Austin have recently developed a nonlinear meta-mirror that doubles the frequency of the light it reflects.

Nonlinear materials are rare in Nature and are generally not too efficient, requiring high intensities and great distances for the light to propagate through. Metamaterials however are completely unnatural as their optical and electrical properties have been tuned to something that would normally be impossible. Using metamaterials though, the researchers were able to build a device just 400 nanometers thick that would bump the wavelength of light from 8 micrometers up to 4 micrometers; doubling the frequency. Unlike natural nonlinear materials, this device is able to convert light with intensities near that of laser pointers.

The creation of such an efficient and small nonlinear optical system could have many impacts on future optical systems, such as miniaturizing some laser systems. These systems may not be ones in our electronics though, but instead those used in advanced sensors for finding chemicals and explosives, as well as biomedical research and more.

Source: University of Texas at Austin



Exploring Nanofluids for Liquid Cooling

Category: Science & Technology
Posted: July 7, 2014 06:17AM
Author: Guest_Jim_*

Keeping electronics cool is paramount whenever you are trying to get the best performance out of them, and when the electronics most fit in a small space. There are many methods of cooling, including liquid cooling systems. Reported in the American Chemical Society's journal Industrial & Engineering Chemistry Research is research to find if nanofluids could be used to improve liquid cooling systems.

Nanofluids are liquids, like water, that contain metallic nanoparticles. Research has been done before to see if they could have a use for cooling electronics, but this new research is the first to consider what kinds of nanofluids may be best, and why. Starting with a microchannel heat sink to replicate operating electronics, the researchers used three different nanofluids to cool it, and measured certain properties. Specifically the researchers looked at how well the nanofluids transferred heat, how much energy they lost, the added friction, and their pumping power.

As it turned out, all three nanofluids performed better than water, with a nanofluid consisting of copper oxide and water doing the best overall. Of course more work will have to be done to identify what could be the best nanofluid for wide use, but this research starts us on the path to finding it.

Source: American Chemical Society



Building Superconducting Circuits Within Silicon

Category: Science & Technology
Posted: July 4, 2014 05:58AM
Author: Guest_Jim_*

Silicon is the material for many modern technologies and has a large industry around it, which is why many are trying to develop future technologies that utilize silicon. Many would like to see silicon used to create quantum systems, but this is not easy to achieve in part because quantum systems are very susceptible to environmental noise. Researchers at the Joint Quantum Institute though, have developed a theoretical way to build superconducting wires and quantum circuits within silicon crystals, with the ability to carry qubits.

About a decade ago, it was discovered that by doping silicon correctly, it could be made to superconductor at temperatures just above absolute zero. Since then the ability to dope silicon has improved to the point that we could potentially build superconducting 'wires' on silicon with atomic precision. The researchers propose using the tip of a scanning tunneling microscope to remove hydrogen atoms from the surface of silicon, allowing the doping gas phosphine to be added. Once the silicon has been successfully doped to form wires, Josephson tunnel junctions, and weak links, which are the building blocks of superconducting circuits, crystalline silicon can be used to cover it all, protecting it from the environment. The result is superconducting circuitry, guarded from environmental noise, capable of carrying spin-based quantum bits.

While the possible applications of superconducting circuitry are decidedly interesting on their own, this research could also be used to create other superconducting-semiconductor devices with exotic properties. It could even be used learn more about superconductivity itself.

Source: Joint Quantum Institute



Getting Closer to Solving Combustion Mystery

Category: Science & Technology
Posted: July 3, 2014 02:04PM
Author: Guest_Jim_*

When most people look at a flame, they likely do not think about the many chemical processes involved. For those that do consider the mechanics of combustion though, there has been a mystery for some time about how soot and compounds are formed. Researchers at Berkeley Lab and the University of Hawaii though have finally found the first step in the process, which could lead to many interesting and useful discoveries.

Under ideal conditions, combustion should just create carbon dioxide and water vapor. Reality is hardly ideal though, and so we see fumes and particulates, such as soot, created as well. The mechanisms that convert gas-phase molecules into these solid particles have been theorized for some time, but now the researchers have experimental evidence for what happens. One family of theories called HACA (hydrogen abstraction-acetylene addition) involves benzene molecules, which are a ring of six carbon atoms with six hydrogen atoms connected, that lose a hydrogen atom and have a tail of acetylene take its spot. Another acetylene molecule eventually attaches to the first, making the tail long enough to curl around and attach to the original benzene ring. This double-ring molecule, called naphthalene, is what eventually develops into soot and other macro molecules.

To identify the mechanism, the researchers created a combustion environment and let the process start before sending the molecules into a mass spectrometer that identified the naphthalene and benzene with acetylene tail. This supports the version of HACA that has the benzene forming a single tail, instead of multiple.

How this matters is that by better understanding the real-world mechanisms of combustion, it may be possible to develop fuels that burn more closely to ideal, making them more efficient and cleaner. Also these mechanisms have implications for how gases emitted by stars can become the carbon-based matter we find in space.

Source: Berkeley Lab



Shooting Off Nanotubes to Unzip Them

Category: Science & Technology
Posted: July 3, 2014 06:54AM
Author: Guest_Jim_*

Depending on its form, carbon can be a very useful material with special properties, but producing the proper form can be difficult and messy. Typically the methods used are chemical in nature, which can leave residues that have to be cleaned off and may be tricky to work with. Researchers at Rice University however have found a means to create graphene nanoribbons mechanically, and this could have some large impacts on future technologies.

To make graphene nanoribbons, one starts with carbon nanotubes, which are essentially the ribbons wrapped into a cylinder. By unzipping them you have the desired nanoribbons, and traditional methods applied chemistry to trigger the unzipping, which then requires cleaning the ribbons. The Rice researchers discovered that nanotubes could also be unzipped by firing them at 15,000 miles per hour at a target in a vacuum chamber. If the nanotubes strike the target along their length, the impact will crush the tube walls and cause them to unzip. Nanotubes that strike end first or at a steep angle though just crumbled. The researchers were firing the nanotubes at that speed to find possible applications for space missions, as such hypervelocity impacts are used to test projectiles on shields, spacecraft, and satellites.

By providing an easy and clean means to produce high-quality graphene nanoribbons, this research could help make them more accessible for future technologies. Thanks to their superb electrical properties, graphene nanoribbons could one day be used to create advanced electronic materials.

Source: Rice University



Researchers Suggest Incorporating Sustainability into Video Games

Category: Science & Technology
Posted: July 2, 2014 05:23PM
Author: Guest_Jim_*

A truth of all topics, great and small, is the difficulty to spread awareness and information on the subject. Indeed there are many topics that are many decades old that are still woefully misunderstood by many, so finding ways to familiarize people with them is crucial. Researchers at Oregon State University have recently suggested that the topic of sustainability could be brought into video games to increase awareness amongst gamers, by presenting us with related puzzles to solve.

By bringing sustainability concepts to video games, the researchers hope to have an approach that is neither pedantic nor educational, but still satisfying and informative through fun and challenge. Specifically four areas the researchers would like to see in more games are: a shift away from growth as a goal, as it would eventually be unsustainable; scavenging instead of combat to collect resources; more complex social interactions to foster social collaborations; and more complex resource strategies with long-term consequences, and interdependencies between resources.

Already there are some games with some of these elements, such as EVE Online, with its economy, and DayZ with its scavenging and player interactions. The researchers would like to see more games and mechanics that encourage thought on sustainability.

Source: Oregon State University



Net-Zero House Succeeds Goal

Category: Science & Technology
Posted: July 2, 2014 06:39AM
Author: Guest_Jim_*

Anyone who has had to pay a power bill or seen rates increase can understand one reason why energy efficiency is important. Sometimes it feels like anything that could reduce usage would be worth it, but could it be possible for a home to zero net energy usage over a year? That is a question researchers at NIST decided to test and the year is up, with great success.

The Net-Zero Energy Residential Test Facility (NZERTF) is a four-occupant house and laboratory in Maryland with many technologies to reduce energy usage, or to even produce energy. There are solar panels on the roof, a geothermal system underground, a solar water-heating system, and the house was built with double the insulation level. Inside the home had all of the appliances you can find around your own house, with extra equipment to control and monitor them, in order to simulate the use of a four-person family. After a year, which included severe weather, the home not only met the net-zero energy goal but exceeded it with a 491 kilowatt hour surplus. In total it used 13,086 kWh, which was 3000 kWh more than expected with normal weather, but roughly 14,000 kWh less than a comparable Maryland home, built to state energy standards, would use.

With this experiment done, and the point of a net-zero home proven, the NZERTF will continue to be used to test technologies and measures to reduce energy use and improve efficiency, with an aim at reducing costs. The researchers estimate the technologies used and efficiency-enhancing construction would add about $162,700 onto the cost of a comparable home built to Maryland's building code, when totaled together.

 

 

Source: NIST



New Record for Smallest Force Measured

Category: Science & Technology
Posted: July 1, 2014 02:04PM
Author: Guest_Jim_*

Sometimes small things can mean very big things, but before those big things can happen, you have to detect the small things. Detecting the almost infinitesimal is hardly easy though, but researchers at Berkeley Lab and the University of California, Berkeley have recently measured a force of roughly 42 yoctonewtons (yN). That would be 0.000000000000000000000042 (42*10-24) Newtons, and one ounce of force is 0.278 N (or 2.78*1023 times greater).

This ultrasensitive detector uses an optical trap to hold and cool a cloud of rubidium atoms. Two standing-wave light fields are what actually trap the atoms and isolate them from the external environment. By modulating one of the fields, the cloud's center of mass can be moved, and this movement can be picked up by another, probe beam of light. The key aspect of this detector is that it decouples the atoms from the environment, which allows the measurement to approach the Standard Quantum Limit, which is the smallest force that can be measured, according to the Uncertainty principles. The closest we have gotten to the SQL before was six to either orders of magnitude, but this got us to just four times above it.

The ability to measure such unbelievably small forces could impact Newtonian physics and General Relativity. We have to be able to measure forces, specifically gravity, at very small scales to answers some of the questions these fields present us with.

Source: Berkeley Lab



Integrating Sensors into Optical Fiber

Category: Science & Technology
Posted: July 1, 2014 06:50AM
Author: Guest_Jim_*

Getting information can be of vital importance for many systems and situations, but sometimes the environment is too harsh to use traditional sensors. Specialized sensors have to be developed then, and some can be very complicated and inelegant. As published in the Optical Society's Optics Letters journal, a new sensor system has been developed that fits inside a single optical fiber, and sets an impressive record.

The researchers were inspired to develop simpler sensors after seeing what NASA has to do to measure liquid hydrogen in microgravity. They turned to fiber optics because they realized that the cables can deliver energy just as they can carry signals, so sensors integrated into the cables can be powered. This power enables a variety of active sensors and devices to be built into the cable, such as gas flow sensors and devices to convert optical energy into ultrasonic energy and microwaves. Hundreds of these could be put into a single fiber, and by the nature of fiber optics, they can be very resilient. Already the researchers have built a gas flow sensors that can operate at temperatures above 800 ºC, which is two hundred degrees above other sensors.

Potentially these sensing fiber optics could be used in nuclear reactors, deep geothermal drill cores, and in outer space. The researchers are now looking to see what else they can carry along optical cables, perhaps by changing its shape and size.

Source: The Optical Society



Making Solar Panels Less Expensive with Tofu Ingredient

Category: Science & Technology
Posted: June 30, 2014 01:53PM
Author: Guest_Jim_*

While a roof covered with solar panels can look very clean and harmless, manufacturing those panels can be anything but. Some of the materials used to create solar panels can be highly toxic and make special safety and disposal methods necessities. Researchers at the University of Liverpool however, have discovered a potential replacement for one of these toxic chemicals, and it is actually found in tofu, bath salts, and is used for de-icing roads.

Magnesium chloride is found in seawater and used in many products already, demonstrating its safety. At $0.001 per gram, it is also relatively cheap, especially compared to cadmium chloride at $0.3 per gram. The reason the latter chemical is used in solar panels is to improve the efficiency of some of the cheapest solar cells made today. Thin films of cadmium telluride can be cheaply turned into solar cells that can convert about 2% of light into electricity, but by applying cadmium chloride, the efficiency can surpass 15%. As it turns out though, magnesium chloride can have the same affect, at a fraction of the cost and much more safely.

To test magnesium chloride, the researchers applied it to solar cells at a bench using a spray gun from a model shop. Applying cadmium chloride requires the use of a fume cupboard to prevent exposure, for comparison.

Source: University of Liverpool



Video Game Behavior Linked to Pro-Social Behavior

Category: Science & Technology
Posted: June 30, 2014 07:11AM
Author: Guest_Jim_*

As a gamer, it can be very annoying to see one of my interests and passions regularly blamed for violent crimes. This makes research into video games all the more interesting to me, to find at least more truth about the topic. Researchers at the University at Buffalo have recently studied how immoral behaviors in video games can affect people, and the result is definitely interesting.

With the plethora of video games currently available, all manner of behaviors and acts have been committed in one or another, including some that are particularly morally repugnant. For this study, the researchers had some of their 185 subjects play a shooter as a terrorist, some as a UN soldier, and asked others to recall guilt-inducing acts they had committed. Afterward they were all asked to fill out a questionnaire and guilt scale. The researchers found that the subjects felt more strongly the moral foundations they violated in the game. Because the players felt guilty about a behavior from the game, they became more morally sensitive to those behaviors outside of the game, according to the answers they provided.

This research aligns with similar studies that also considered how mediated and indirect experiences affect one's morality, though those other studies used real-world behaviors, instead of virtual worlds. It will definitely be interesting to see how video games are considered in more moral psychology studies in the future.

Source: University at Buffalo



Magnetic Hose Created to Transmit Magnetic Fields

Category: Science & Technology
Posted: June 27, 2014 02:03PM
Author: Guest_Jim_*

Magnetic fields have had many uses for many decades, including storing information and generating electricity. Despite their relatively common use, there has been no technology to guide and transmit static magnetic fields. Until now that is, thanks to researchers at Universitat Autònoma de Barcelona.

Comprised of a ferromagnetic cylinder, wrapped with a superconductor, the magnetic hose developed by the researchers can actually transmit static magnetic fields from one inlet to multiple outlets. This is similar to how fiber optics can manipulate light, and could lead to a new field of technology and research, just as fiber optics did. As it is now, the magnetic hose is four times more efficient than modern techniques to transmit magnetic fields, but this could improve. According to the theories that enable the hose to work, by wrapping the ferromagnetic cylinder in alternating thin layers of superconductor and ferromagnetic material, the efficiency could increase further.

Source: Universitat Autònoma de Barcelona



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