Better heat exchangers using garbage bags

 

The same plastic as in garbage bags makes an efficient heat exchanger in power plants by creating microchannels. Credit: Joshua Pearce The plastic used to make garbage bags also makes a good base for building low-temperature heat exchangers. Joshua Pearce, a researcher at Michigan Technological University, has worked with a collaborative group funded by the Advanced Research Projects Agency-Energy. Pearce's team helped design and make the plastic-based heat exchangers to be used in power plants. The key is expanded microchannel structures, says Pearce, who is an associate professor of materials science and engineering along with electrical and computing engineering at Michigan Tech. He constructs the exchangers layer by layer with a laser welder -- like in 3-D printing -- and then puffs up the plastic. The resulting Michelin Man-like pattern creates microchannels, which allow air or water to pass through, and that transfers heat from the hot side to the cold side of the exchanger. "The temperature and pressure requirements for the air cooled condensers on power plants are modest," Pearce says, explaining that allows the team to use polymer heat exchangers to improve efficiency and cut costs. "This is really important as conventional power plants are finding it more and more difficult to compete with the recent price drops in renewable energy sources like solar." "Now, our work is to try and take these small envelopes that we've made successfully and transfer them to a bigger scale," Pearce says. "Even if one day all central power plants are replaced by more nimble distributed generation, heat exchangers may be in your house or your vehicle made out advanced garbage bags, which can increase the heat recovery and save you money at home." Story Source: The above post is reprinted from materials provided by Michigan Technological University. Note: Materials may be edited for content and length.

11 Habits You Need to Give Up to Be Happy

 

by Lisa H. Are your habits and routines sucking up your happiness? Oftentimes we unknowingly hold on to little, obsessive habits that cause us a great deal of stress and unhappiness.  Even when we feel that something is wrong, we fail to seek the changes we need to make and instead cling to what’s not working, simply because it’s what we’re accustomed to. It’s time to make a change.  It’s time to give up the habits that no longer serve your well-being and embrace the positive changes you need to be happy. Today is the perfect day to give up… 1.  Worrying about… everything. Worry is the biggest happiness slayer ever.  Worry steals all of your attention and gives the illusion that you are working through a problem when you are not.  As Van Wilder said, “Worrying is like a rocking chair. It gives you something to do, but it doesn’t get you anywhere.” People worry for all sorts of reasons: to escape reality, fear of the unknown, resistance to change, lack of confidence, etc. Stopping worry, like everything else takes practice; the more you do it, the better you will become at discerning when you are no longer controlling your thoughts and they are controlling you. Tip:  To jolt yourself out of worry, ask yourself what you can do “right now” to make your life more pleasant and then do that! 2.  Constant, deliberate, people-pleasing. Contrary to what you may think, saying “yes” to every request that is made of you is not nice.  First, it is not nice to you because it can leave you emotionally, mentally and physically drained.  And second, it is not nice to the other person, because it deceives them into thinking that you have the time, energy and other resources available to make what they want happen, when you do not. Generally people who carry out the duties of others at the expense of themselves have low self-esteem and high levels of unhappiness.  They need the approval of others to make themselves feel worthy. Tip:  To combat people-pleasing behavior, learn to say “no.”  Oftentimes when you say “no” to someone else, you are really saying “yes” to YOU. 3.  Procrastinating. Procrastination is stagnation.  There is no other way to say it.  When you procrastinate, nothing good in your life is happening. We procrastinate for all sorts of reasons.  When we are afraid of the outcome, we are unsure how to complete the task and when we just don’t feel like taking action. And the thing is, we spend more time aggravating ourselves with worry about how long or how difficult the task is going to be rather than just doing it.  More often than not, if you just start your task, you will be pleasantly surprised at how easily you are able to accomplish it. Tip:  When you feel yourself getting ready to procrastinate, silently say “stop” to yourself, refocus and begin again by taking calculated action that will lead to the results you desire.  (Read Getting Things Done.) 4.  Living in the past. The past is gone for good and yet we spend so much time thinking about what happened yesterday, at the complete expense of today.  Keeping your thoughts stuck in the past is especially detrimental to your contentment.  You are a product of your environment.  Your environment has helped to shape how you think and feel about yourself.  Everyone has been presented with life challenges along their journey – you aren’t alone.  It is whether you are stuck in the patterns of the past or have moved past them. Tip:  If you are harboring resentment, anger, frustration or other negative feelings from your past, don’t ignore these feelings.  Do something constructive about it so that you can move into the present. 5.  Always looking past the present moment in anticipation of the next. We spend so much time in this moment, wanting to be in the next one, that we are missing our lives. For example, while taking a shower, you might be thinking about that cup of coffee you want to make, and while you are drinking your coffee, you might be thinking about your commute to work.  You are never consciously present right where you are and therefore cannot enjoy the moment you are in – the moment we call “life.” Tip:  Now is the only time you have.  Now is life.  Make sure you are fully experiencing it. 6.  Judging others. When you judge someone else, you suffer.  It is an outward display of inward inferiority and anger.  No one person is better than another.  The individual who cleans the bathroom at a fast food restaurant is no less of a person than the CEO that uses it. Tip:  Understand that we are all part of the collective human race.  We are one.  Your joy is my joy and your suffering is my suffering.  (Read Buddha’s Brain.) 7.  Comparing your story to everyone else’s. It is good to notice what others are doing from time to time.  After all, that is what helps us outline what we want and don’t want in our own lives.  But comparing yourself to everyone else every step of the way takes it too far.  You know when this happens – when you stop living your dreams or start living theirs. Tip:  You are unique.  No matter how hard you try to be like someone else, you will never be them, and you shouldn’t want to be. 8.  Shame. Shame is a deep, debilitating emotion, with complex roots.  Its cousins are guilt, humiliation, demoralization, degradation and remorse.  After experiencing a traumatic event, whether recent or in the distant past, shame can haunt victims in a powerful and often unrecognized manner. Shame impairs the healing and recovery process causing victims of trauma to stay frozen, unable to forgive themselves for being in the wrong place at the wrong time.  Shame leaves victims with feelings of sadness and pain at the core of their being.  They are unable to feel the fullness of joy in their lives. If you feel any shame at all, acknowledge it upfront.  Decide to experiment on forgiving yourself and letting go of the shame.  How long can you go without reminding yourself about the shameful thoughts and feelings?  How would life be different or better if you were able to forgive yourself?  Who can you talk to about this? Tip:  The more you forgive yourself, the more time you have to focus your mind on happier times. 9.  Disorganization and laziness. We complain that there are not enough hours in a day to accomplish all that we want, yet our laziness often leads us to many wasteful hours of disorganization.  The discipline it takes to sort through a messy desk, counter, closet or mind take time.  Becoming organized is a habit.  Start with something small, like your office desk or even making your bed after you get up. Tip:  Studies have shown that people who make their beds are statistically more productive, profitable and peaceful in their lives and careers.  Interesting, isn’t it?  But not surprising. 10.  Fear of… everything. Fear is one of the biggest reasons why we don’t move ahead in our lives.  Fear of failing and fear of succeeding.  Fear of the unknown.  Fear of fear.  As long as we are alive, we are prone to some level of fear.  Ironically, to feel alive we must overcome that fear with action.  As Bill Cosby once said, “Decide that you want it more than you are afraid of it.” Tip:  Courage is not the absence of fear, but rather the judgment that your happiness and growth is more important than it.  Do something every day that stretches your comfort zone and helps you face what your fear.  (Read Daring Greatly.) 11.  The need to be busy. Busyness is often confused with productivity.  They are two different things.  Busy is running in place on a treadmill; productivity is actually getting somewhere worthwhile.  These days technology gives us this constant feeling that there is so much to do and not enough time to do it.  We are always connected to something that wants our attention, or something that could be done.  This feeling creates stress.  The more behind you think you are, the more stressed out you are going to feel. Stress is not good for you.  It makes it difficult to think, connect with others and it is associated with a plethora of physical ailments that lead to unhappiness. Tip:  Stop trying to be busy.  Put first things first and give up the rest.  Organization, meditation, improved time management and efficiency and a change in perception are all ways to manage stress.  You must learn to let go.  Release the excess.  You were never able to do it all anyway. Your turn… What would you add to the list?  What’s one obsessive habit or routine that has been making you unhappy?  What can be done about it?  Share your thoughts by leaving a comment below. Author Bio:  Lisa H. is a mother, entrepreneur, self-proclaimed introvert and practitioner of all things happy.  With her blog, Getting to Zen, she aims to inspire you to re-awaken your spirit, live fearlessly and do what you love. Photo by: Alex Proimos source: http://www.marcandangel.com

Look, Ma, No hands !

 

The ANICORN Series 000 contemporary timepiece equips a unique concentric disc system to display the time in an entirely new way. Instead of using hands and flicks as index, 3 independent concentric discs, graduated for the hours, minutes and seconds are marked out on the center disc to make it as easy to tell the time as it is attractive to look at. Black, red, or blue? Get em’ here!

Designer: ANICORN WATCHES

 

Tactical throwable cameras

 

Fri, 06/26/2015 - 11:40am Rob Matheson, MIT News Office   The background photograph was taken using the softball-sized camera, the Explorer (shown here). Image: Jose-Luis Olivares/MIT (photo courtesy of Bounce Imaging) Unseen areas are troublesome for police and first responders: Rooms can harbor dangerous gunmen, while collapsed buildings can conceal survivors. Now Bounce Imaging, founded by an Massachusetts Institute of Technology (MIT) alumnus, is giving officers and rescuers a safe glimpse into the unknown. In July, the Boston-based startup will release its first line of tactical spheres, equipped with cameras and sensors, that can be tossed into potentially hazardous areas to instantly transmit panoramic images of those areas back to a smartphone. “It basically gives a quick assessment of a dangerous situation,” says Bounce Imaging CEO Francisco Aguilar MBA ’12, who invented the device, called the Explorer. Launched in 2012 with help from the MIT Venture Mentoring Service (VMS), Bounce Imaging will deploy 100 Explorers to police departments nationwide, with aims of branching out to first responders and other clients in the near future. The softball-sized Explorer is covered in a thick rubber shell. Inside is a camera with six lenses, peeking out at different indented spots around the circumference, and LED lights. When activated, the camera snaps photos from all lenses, a few times every second. Software uploads these disparate images to a mobile device and stitches them together rapidly into full panoramic images. There are plans to add sensors for radiation, temperature, and carbon monoxide in future models. For this first manufacturing run, the startup aims to gather feedback from police, who operate in what Aguilar calls a “reputation-heavy market.” “You want to make sure you deliver well for your first customer, so they recommend you to others,” he says. Steered right through VMS Over the years, media coverage has praised the Explorer, including in Wired, the BBC, NBC, Popular Science and Time—which named the device one of the best inventions of 2012. Bounce Imaging also earned top prizes at the 2012 MassChallenge Competition and the 2013 MIT IDEAS Global Challenge. Instrumental in Bounce Imaging’s early development, however, was the VMS, which Aguilar turned to shortly after forming Bounce Imaging at the MIT Sloan School of Management. Classmate and U.S. Army veteran David Young MBA ’12 joined the project early to provide a perspective of an end-user. “The VMS steered us right in many ways,” Aguilar says. “When you don’t know what you’re doing, it’s good to have other people who are guiding you and counseling you.” Leading Bounce Imaging’s advisory team was Jeffrey Bernstein SM ’84, a computer scientist who had co-founded a few tech startups—including PictureTel, directly out of graduate school, with the late MIT professor David Staelin—before coming to VMS as a mentor in 2007. Among other things, Bernstein says the VMS mentors helped Bounce Imaging navigate, for roughly two years, in funding and partnering strategies, recruiting a core team of engineers and establishing its first market—instead of focusing on technical challenges. “The particulars of the technology are usually not the primary areas of focus in VMS,” Bernstein says. “You need to understand the market, and you need good people.” In that way, Bernstein adds, Bounce Imaging already had a leg up. “Unlike many ventures I’ve seen, the Bounce Imaging team came in with a very clear idea of what need they were addressing and why this was important for real people,” he says. Bounce Imaging still reaches out to its VMS mentors for advice. Another “powerful resource for alumni companies,” Aguilar says, was a VMS list of previously mentored startups. Over the years, Aguilar has pinged that list for a range of advice, including on manufacturing and funding issues. “It’s such a powerful list, because MIT alumni companies are amazingly generous to each other,” Aguilar says. The right first market From a mentor’s perspective, Bernstein sees Bounce Imaging’s current commercial success as a result of “finding that right first market,” which helped it overcome early technical challenges. “They got a lot of really good customer feedback really early and formed a real understanding of the market, allowing them to develop a product without a lot of uncertainty,” he says. Aguilar conceived of the Explorer after the 2010 Haiti earthquake, as a student at both MIT Sloan and the Kennedy School of Government at Harvard University. International search-and-rescue teams, he learned, could not easily find survivors trapped in the rubble, as they were using cumbersome fiber-optic cameras, which were difficult to maneuver and too expensive for wide use. “I started looking into low-cost, very simple technologies to pair with your smartphone, so you wouldn’t need special training or equipment to look into these dangerous areas,” Aguilar says. The Explorer was initially developed for first responders. But after being swept up in a flurry of national and international attention from winning the $50,000 grand prize at the 2012 MassChallenge, Bounce Imaging started fielding numerous requests from police departments—which became its target market. Months of rigorous testing with departments across New England led Bounce Imaging from a clunky prototype of the Explorer—“a Medusa of cables and wires in a 3D-printed shell that was nowhere near throwable,” Aguilar says—through about 20 further iterations. But they also learned key lessons about what police needed. Among the most important lessons, Aguilar says, is that police are under so much pressure in potentially dangerous situations that they need something very easy to use. “We had loaded the system up with all sorts of options and buttons and nifty things—but really, they just wanted a picture,” Aguilar says. Neat tricks Today’s Explorer is designed with a few “neat tricks,” Aguilar says. First is a custom, six-lensed camera that pulls raw images from its lenses simultaneously into one processor. This reduces complexity and reduces the price tag of using six separate cameras. The ball also serves as its own wireless hotspot, through Bounce Imaging’s network, that a mobile device uses to quickly grab those images—“because a burning building probably isn’t going to have Wi-Fi, but we still want … to work with a first responder’s existing smartphone,” Aguilar says. But the key innovation, Aguilar says, is the image-stitching software, developed by engineers at the Costa Rican Institute of Technology. The software’s algorithms, Aguilar says, vastly reduce computational load and work around noise and other image-quality problems. Because of this, it can stitch multiple images in a fraction of a second, compared with about one minute through other methods. In fact, after the Explorer’s release, Aguilar says Bounce Imaging may option its image-stitching technology for drones, video games, movies, or smartphone technologies. “Our main focus is making sure the [Explorer] works well in the market,” Aguilar says. “And then we’re trying to see what exciting things we can do with the imaging processing, which could vastly reduce computational requirements for a range of industries developing around immersive video.” Source: Massachusetts Institute of Technology

Could Flying Bikes, Cars Be Next? Toyota and U.S. Army Explore

 

Hoverbikes and boards that lift off the ground are no longer sci-fi. Even the U.S. Army is considering how to use them. Lexus built its Hoverboard, which uses magnets and liquid nitrogen cooled superconductors to lift off the ground, for an ad campaign. Photograph courtesy Lexus Hovering technology, once Hollywood sci-fi, is gaining ground in the real world. The U.S. Army is looking at the “world’s first flying motorcycle,” and Toyota’s luxury brand Lexus has built its own hoverboard. Yet these and other levitating wonders won’t hit the market anytime soon. They still have to undergo safety testing and regulatory scrutiny. And some are simply meant to amuse. Lexus’ new Hoverboard, for example, isn’t the forerunner of a flying car that Toyota says it’s been studying. “It’s definitely something that works, but it’s not something we plan to sell,” says Lexus spokesman Moe Durand of the hoverboard, unveiled this week in a company video. It uses magnets and liquid nitrogen-cooled superconductors to lift a rider off the ground. So far, it only works when magnets are embedded underneath the concrete surface. “It’s really just for an ad,” Durand says, citing the “Amazing in Motion” ad campaign to showcase Lexus’ innovation. Though Lexus didn’t build it as part of a push toward a flying car, he says it could eventually lead in that direction: “Is it dipping our toe in the water? Maybe.” An increasing number of companies, though, are vying to commercialize their hovercraft. Their prototypes may not look like Marty McFly’s board in the 1989 movie Back to the Future II, but they’re aiming to use magnetic levitation to do all sorts of incredible things—transport troops over difficult terrain, move passengers in Elon Musk’s vision of sonic tubular travel, or even lift buildings to avoid earthquake damage. Chris Malloy built a helicopter-like craft in his garage in suburban Sydney, Australia. His website says he “combined the simplicity of a motorbike with the freedom of a helicopter to create the world’s first flying motorcycle.” Now he’s the managing director of Malloy Aeronautics, a company based in the United Kingdom. “We’re doing a feasibility study for them,” Malloy says of the U.S. Army, noting his Hoverbike can do search and rescue missions, cargo delivery, disaster relief, and surveillance. He says his craft, designed to come in manned and unmanned versions, can do what helicopters do—at a lower cost, in tighter spaces, and without pilots. This is the original prototype of the Hoverbike, which has two propellers. The current one is a quad-copter with four propellers. Photograph courtesy Malloy Aeronautics He declined to give specifics about the project. At the Paris Air Show earlier this month, Maryland Lt. Governor Boyd Rutherford announced that Malloy’s company—along with SURVICE Engineering Co., a Maryland-based defense firm—is working to develop the Hoverbike for the U.S. military as a new class of Tactical Reconnaissance Vehicle. Malloy says he developed the Hoverbike for commercial, not military, use. “We’ve had lots of people who want to place orders,” he says, noting he’s not yet taking them. “We don’t want to hurry our product into the market.” Technically, he says the company could begin production now, but he needs to do rigorous testing to prove its safety. He expects that could take at least three to five years, and he doesn’t have the market to himself. “We have competitors,” he says, noting companies in New Zealand and elsewhere with similar prototypes. Simpler hovercraft are emerging, too. In California, Greg Henderson has built the Hendo, a hoverboard that he says uses one fourth as much energy as a helicopter to lift the same weight. (Find out what it’s like to ride one.) In October, his company Arx Pax plans to debut a new version that’s smaller, lighter, and more powerful. The story is part of a special series that explores energy issues. For more, visit The Great Energy Challenge. On Twitter: Follow Wendy Koch and get more environment and energy coverage at NatGeoEnergy.

Minimally invasive heart surgery

 

Definition By Mayo Clinic Staff In minimally invasive heart surgery, heart (cardiac) surgeons perform heart surgery through small incisions in the right side of your chest, as an alternative to open heart surgery. Surgeons operate between the ribs and don't split the breastbone (sternotomy), which results in less pain and a quicker recovery for most people. In minimally invasive surgery, your heart surgeon has a better view of some parts of your heart than in open heart surgery. As in open surgery, minimally invasive heart surgery requires stopping your heart temporarily and diverting blood flow from your heart using a heart-lung machine. Surgeons perform many minimally invasive heart surgeries, including: Aortic valve surgery Atrial septal defect closure, including patent foramen ovale Atrioventricular canal defect (also called atrioventricular septal defect) surgery Heart valve surgery to treat heart valve disease Maze heart surgery to treat atrial fibrillation Mitral valve surgery Saphenous vein harvest (removing a vein from your leg) for coronary bypass surgery Tricuspid valve surgery Your doctor will work with you to determine whether minimally invasive heart surgery is an option. If you've had prior heart surgery or heart disease, you generally aren't a candidate for minimally invasive heart surgery. Your doctor also may perform tests and review your medical history to determine whether you're a candidate for minimally invasive heart surgery. Mayo Clinic offers robot-assisted surgery or thoracoscopic minimally invasive heart surgery. Advantages Minimally invasive heart surgery isn't an option for everyone, but it offers many advantages in those for whom it's appropriate. Advantages may include: Less blood loss Lower risk of infection Reduced trauma and pain Shorter time in the hospital, faster recovery and quicker return to normal activities Smaller, less noticeable scars Risks In people for whom minimally invasive heart surgery is appropriate, risks and complications are rare. You may experience these complications, which also may occur in other surgeries: Bleeding Stroke Wound infection Types Mayo Clinic heart surgeons work with an experienced surgical team to perform minimally invasive heart surgery, including robot-assisted heart surgery and thoracoscopic heart surgery. In both types of procedures, surgeons reach your heart through small incisions between the ribs of your chest. Robot-assisted heart surgery. In robot-assisted heart surgery, the exact maneuvers performed in traditional open chest operation are duplicated by the surgeon using robotic arms, rather than his or her hands. During this procedure, your surgeon works at a remote console and views your heart in a magnified high-definition 3-D view on a video monitor. From the remote console, your surgeon's hand movements are translated precisely to the robotic arms at the operating table, which move similarly to the human wrist. A second surgeon and surgical team assists at the operating table, changing surgical instruments attached to the robotic arms. Thoracoscopic surgery. In thoracoscopic surgery (sometimes referred to as a mini-thoracotomy), your surgeon inserts a long, thin tube (thoracoscope) containing a tiny high-definition video camera into a small incision in your chest. Your surgeon repairs your heart using long instruments inserted through small incisions between your ribs.   June 06, 2015

A new means to killing harmful bacteria

 

Thu, 06/25/2015 - 11:50am Helen Knight, MIT News correspondent In this illustration, phagemid plasmids infect a targeted bacteria. Image: Christine Daniloff and Jose-Luis Olivares/MIT (plasmid illustration courtesy of the researchers) The global rise in antibiotic resistance is a growing threat to public health, damaging our ability to fight deadly infections such as tuberculosis. What’s more, efforts to develop new antibiotics are not keeping pace with this growth in microbial resistance, resulting in a pressing need for new approaches to tackle bacterial infection. In a paper published online in Nano Letters, researchers at Massachusetts Institute of Technology (MIT), the Broad Institute of MIT and Harvard and Harvard Univ. reveal that they have developed a new means of killing harmful bacteria. The researchers have engineered particles, known as “phagemids,” capable of producing toxins that are deadly to targeted bacteria. Bacteriophages—viruses that infect and kill bacteria—have been used for many years to treat infection in countries such as those in the former Soviet Union. Unlike traditional broad-spectrum antibiotics, these viruses target specific bacteria without harming the body’s normal microflora. But bacteriophages can also cause potentially harmful side effects, according to James Collins, the Termeer Professor of Medical Engineering and Science in MIT’s Dept. of Biological Engineering and Institute of Medical Engineering and Science, who led the research. “Bacteriophages kill bacteria by lysing the cell, or causing it to burst,” Collins says. “But this is problematic, as it can lead to the release of nasty toxins from the cell.” These toxins can lead to sepsis and even death in some cases, he says. A gentler burst In previous research, Collins and his colleagues engineered bacteriophages to express proteins that did not actually burst the cells, but instead increased the effectiveness of antibiotics when delivered at the same time. To build on this earlier work, the researchers set out to develop a related technology that would target and kill specific bacteria, without bursting the cells and releasing their contents. The researchers used synthetic biology techniques to develop a platform of particles called phagemids. These particles infect bacteria with small DNA molecules known as plasmids, which are able to replicate independently inside a host cell. Once inside the cell, the plasmids are engineered to express different proteins or peptides—molecules made up of short chains of amino acids—that are toxic to the bacteria, Collins says. “We systematically tested different antimicrobial peptides and bacterial toxins, and demonstrated that when you combine a number of these within the phagemids, you can kill the great majority of cells within a culture,” he says. The expressed toxins are designed to disrupt different cellular processes, such as bacterial replication, causing the cell to die without bursting open. Precise targeting The phagemids will also only infect a specific species of bacteria, resulting in a highly targeted system, Collins says. “You can use this to kill off very specific species of bacteria as part of an infection therapy, while sparing the rest of the microbiome,” he says. When the researchers monitored the response of the bacteria to repeated reinfection with the phagemids, they did not witness signs of significant resistance to the particles. “This means you can do multiple rounds of delivery of the phagemids, in order to get a more effective therapy,” he says. This is in contrast to repeated infection with bacteriophages, where the researchers found that the bacteria did develop resistance over time. Although Collins acknowledges that bacteria will ultimately develop resistance to any stress that is placed upon them, the research suggests that it is likely to take them far longer to develop resistance to phagemids than to conventional bacteriophage therapy, he says. A “cocktail” of different phagemids could be given to patients to treat an unclassified infection, in a similar way to the broad-spectrum antibiotics used today. But they are more likely to be used in conjunction with rapid diagnostic tools, currently in development, which would allow physicians to treat specific infections, Collins says. “You would first run a fast diagnostic test to identify the bacteria your patient has, and then give the appropriate phagemid to kill off the pathogen,” he says. The researchers are planning to expand their platform by developing a broader range of phagemids. They have so far experimented with a set of phagemids specific to E. coli, but now hope to create particles capable of killing off pathogens such as Clostridium difficile and the cholera-causing bacterium Vibrio cholerea. Source: Massachusetts Institute of Technology

Pointing the way to crack-resistant metals

 

Thu, 06/25/2015 - 11:20am Joe Kullman, Arizona State University. The image shows corrosion of a silver-gold alloy spontaneously resulting in the formation of nanoscale porous structures that undergo high-speed cracking under the action of a tensile stress. It helps demonstrate a discovery by an Arizona State University research team about the stress-corrosion behavior of metals that threatens the mechanical integrity of engineered components and structures.Potential solutions to big problems continue to arise from research that is revealing how materials behave at the smallest scales. The results of a new study to understand the interactions of various metal alloys at the nanometer and atomic scales are likely to aid advances in methods of preventing the failure of systems critical to public and industrial infrastructure. Research led by Arizona State Univ. materials science and engineering professor Karl Sieradzki is uncovering new knowledge about the causes of stress-corrosion cracking in alloys used in pipelines for transporting water, natural gas and fossil fuels, as well as for components used in nuclear power generating stations and the framework of aircraft. Sieradzki is on the faculty of the School for Engineering of Matter, Transport and Energy, one of ASU’s Ira A. Fulton Schools of Engineering. His research team’s findings are detailed in Nature Materials. Using advanced tools for ultra-high-speed photography and digital image correlation, the team has been able to closely observe the events triggering the origination of stress-corrosion fracture in a model silver-gold alloy and to track the speed at which cracking occurs. They measured cracks moving at speeds of 200 mps, corresponding to about half of the shear wave sound velocity in the material. This is a remarkable result, Sieradzki said, given that typically only brittle materials such as glass will fracture in this manner and that gold alloys are among the most malleable metals. In the absence of a corrosive environment these gold alloys fail in the same manner as children’s modeling clay, Sieradzki explained: Roll modeling clay into a cylindrical shape and you can stretch it by a by 100% before it slowly tears apart. In the presence of corrosive environments, silver is selectively dissolved from the alloy causing porosity to form. If this occurs while the alloy is stressed, then the material fails as if it were made of glass. These results provide a deeper understanding of the stress-corrosion behavior of metals such as aluminum alloys, brass and stainless steel that threatens the mechanical integrity of important engineered components and structures. The team’s discoveries could provide a guide for “designing alloys with different microstructures so that the materials are resistant to this type of cracking,” Sieradzki said. Source: Arizona State University

New conductive ink for electronic apparel

 

Thu, 06/25/2015 - 10:45am University of Tokyo Electrodes, wires, and via holes can be printed by a single step printing process. The muscle activity sensor was produced by printing once on each side of the material's surface.  Image: 2015 Someya Laboratory University of Tokyo researchers have developed a new ink that can be printed on textiles in a single step to form highly conductive and stretchable connections. This new functional ink will enable electronic apparel such as sportswear and underwear incorporating sensing devices for measuring a range of biological indicators such as heart rate and muscle contraction. Current printed electronics, such as transistors, light-emitting diodes and solar panels, can be printed on plastic or paper substrates, but these substrates tend to be rigid or hard. The use of soft, stretchable material would enable a new generation of wearable devices that fit themselves to the human body. However, it has proved difficult to make an ink that is both highly conductive and elastic without a complicated multi-step printing process. Now, Prof. Takao Someya's research group at the Univ. of Tokyo's Graduate School of Engineering has developed an elastic conducting ink that is easily printed on textiles and patterned in a single printing step. This ink is comprised of silver flakes, organic solvent, fluorine rubber and fluorine surfactant. The ink exhibited high conductivity even when it was stretched to more than three times its original length, which marks the highest value reported for stretchable conductors that can be extended to more than two and a half times their original length. Using this new ink, the group created a wrist-band muscle activity sensor by printing an elastic conductor on a sportswear material and combining it with an organic transistor amplifier circuit. This sensor can measure muscle activity by detecting muscle electrical potentials over an area of 4x4 square centimeters with nine electrodes placed 2 cm apart in a 3x3 grid. "Our team aims to develop comfortable wearable devices. This ink was developed as part of this endeavor," says Someya. "The biggest challenge was obtaining high conductivity and stretchability with a simple one-step printing process. We were able to achieve this by use of a surfactant that allowed the silver flakes to self-assemble at the surface of the printed pattern, ensuring high conductivity." Source: University of Tokyo

Como Manter-se Motivado Quando Trabalha em Casa

 

O número de pessoas que trabalha em casa está a crescer. No entanto, esta prática é mais difícil do que possa parecer, sendo necessário um alto nível de disciplina e enfrentar o trabalho como qualquer outro. Trabalhar em casa como um profissional – Imagem de Flickr/JeremyOK Segundo alguns estudos estatísticos realizados pela Work From Home Info, existe um elevado número de pessoas que trabalha em casa. Mesmo que esses números sejam relativos aos Estados Unidos, as estatísticas de outros países devem estar próximas dessas, proporcionais à população. Senão vejamos: o desemprego aumenta a olhos vistos e muitas dessas pessoas começam a arranjar soluções por conta própria. No início do processo, é muito provável que tudo comece a partir de casa. Nos Estados Unidos são gerados anualmente 427 biliões de dólares por negócios criados e mantidos a partir de casa e 70% dos americanos preferia ser o seu próprio empregador. Estas são demais razões para considerar o trabalho a partir de casa mais do que um capricho, antes uma realidade. Regras para manter a motivação e produtividade para quem trabalha em casa Trabalhar a partir de casa não é fácil. As distrações existem em maior número comparando com o trabalho tradicional, não existe o contato entre colegas de trabalho (porque muitas vezes não existem colegas de trabalho) e, inclusive, pode não ser uma prática bem vista por familiares e amigos. Por outras palavras, se quer trabalhar a partir de casa tem que ganhar bons hábitos e criar uma reputação, resultados visíveis que comprovem a sua boa escolha. De seguida apresento-lhe um conjunto de práticas que têm como objetivo manter a sua motivação e produtividade em cima quando trabalha em casa. É importante evitar distrações, tratar este trabalho como qualquer outro trabalho, levá-lo a sério e definir horas de verdadeira produtividade. 1. Comece o dia como um profissional Se pensa que por estar a trabalhar em casa não tem um horário e pode fazê-lo de pijama desengane-se. Trabalhar de pijama é depressivo, aos poucos vai sendo cada vez mais difícil tirar da sua cabeça a palavra casa e substitui-la por trabalho. Um bom sinal de que está disponível para trabalhar em casa é cumprir horários e vestir-se como se fosse para o escritório. Crie uma rotina: horas de levantar, pequeno-almoço, vestimenta a rigor, entra às 9 e sai às 5, seja o que for. A história de acordar a qualquer hora, puxar do portátil para a cama e trabalhar não funciona. Se leva o seu trabalho a sério, seja profissional. Artigo Relacionado: Como se Tornar numa Pessoa Madrugadora 2. Maximize o contato com outras pessoas Uma das vantagens do trabalho fora de casa é a possibilidade de conviver com colegas, partilhar opiniões e demonstrar que temos uma voz. Trabalhar a partir de casa tem este senão: vai estar na solidão a maior parte do tempo. Por essa razão, é importante maximizar o contato com o exterior, em termos profissionais, claro. Procure estar perto de clientes e potenciais clientes, outras pessoas que estejam na mesma situação. Se não consegue viver sem socializar, então esta ausência pode ser altamente desmotivadora. Lute contra esse problema e mantenha-se em contato. 3. Agrupe tarefas idênticas Rieva Lesonsky, CEO da GrowBiz Media, aconselha a agrupar tarefas idênticas (aliás, quer trabalhe em casa ou não). “Passar do e-mail para a escrita de uma proposta para uma sessão de brainstorm e voltar novamente ao e-mail vai dispersar a sua energia, uma vez que o seu cérebro tem que realizar mudanças de foco de cada vez que alterna entre tarefas.” Em vez deste vai-vem entre tarefas, agrupe aquelas que são idênticas. “Por exemplo, reserve uma manhã por semana para uma reunião; passe uma hora ao telefone a receber e realizar chamadas; reserve algumas horas para escrever uma proposta. Aos poucos vai entrar no ritmo de cada tarefa que está a realizar e vai ser mais eficaz,” diz Rieva. Artigo Relacionado: “O Multitasking Traz Ineficiência,” diz a Ciência 4. Discipline-se Se trabalhar no escritório pode ser uma tarefa árdua, imagine o que é trabalhar num local que remete para o descanso e paz, para as suas coisas e para o seu espaço, família, etc. O corpo fica mole, as distrações são mais que muitas. Comece a utilizar ferramentas como o RescueTime que lhe permite monitorizar onde gasta o seu tempo para que o possa aproveitar da melhor maneira. É fácil perder tempo a partir de casa – ou são os animais, ou são os filhos, ou cortar a relva do jardim. Não funciona. Trabalhar em casa passa muito por automatizar o cérebro para perceber quando é tempo para trabalhar e quando não é. Se continuar a perder tempo dessa forma nunca o vai conseguir. Artigo Relacionado: 5 Formas de Derrotar a Procrastinação Artigo Relacionado: 5 Práticas Para a Verdadeira Produtividade 5. Faça pausas e exercício Tal como qualquer profissional, as pausas e o exercício são bons catalizadores para o foco. Em casa tem outro benefício: pode aproveitá-las para trabalho caseiro. Se quando trabalha fora de casa as pausas não são mais do que perder algum tempo a não fazer nada, em casa pode tirar o melhor partido delas para realizar outras tarefas. Por outro lado, trabalhar a partir de casa torna a prática de exercício mais facilitada uma vez que evita a perda de tempo entre casa-trabalho e trabalho-casa. Deixou de ter a desculpa da falta de tempo porque o momento exato que serviria para a prática de exercício é precisamente a altura das deslocações. O exercício é benéfico para a sua saúde e para o seu trabalho. Artigo Relacionado: Exercício Físico e Saúde: A Tecnologia à Sua Disposição Se começou agora a trabalhar a partir de casa, ou se tem nos seus horizontes essa possibilidade, fazê-lo é mais difícil do que aparenta. Pelo menos se pretende obter produtividade. Recomendo que crie uma lista com vários pontos relativos ao que deve mudar e implementar para um dia de trabalho em casa bem sucedido. Aos poucos comece a habituar-se a todas essas práticas com disciplina. O truque para o trabalho caseiro é a disciplina.