One car caught my eye—not because of its flashy display or custom chrome wheels, but because of the word “ceramic” emblazoned upon its rear end.
Ceramic? Yes! (To be honest, I not-so-secretly fist pumped and high-fived my way across the floor of the Greater Columbus Convention Center for discovering a blog post on the weekend.)
Upon further research (and a few Internet searches), Mazda’s Ceramic 6 concept car is deceiving because, as far as this gal can tell, the ceramic white paint isn’t ceramic at all. Instead, the satin trim is a nod to the beauty of the craft—an understated yet stately paint job with equally stately (and sporty) silver accent stripes meant to “evoke imagery of flowing fabric and feelings of serenity.” More like a sophisticated gentleman in a white pinstripe suit.
Published on April 4th, 2014 | Edited By: Eileen De Guire
Sheffield University professor John Provis on the durability of “geopolymer” cement, a possible substitution for clinker-based cements. Credit: Wiley; YouTube.
Concrete—aggregate bound together with cement—has been the “go to” building material since ancient times, and evidence suggests that the Romans developed standardized formulations for making cement and mixing concrete. The Romans knew what they were doing—the Pantheon, which was built during the reign of Roman emperor Augustus (27 BC–14 AD), is the largest unreinforced concrete dome in the world despite being more than 2,000 years old.
Concrete is as important as ever and is the most widely used material in the world. Concrete use is even used as an indicator of economic growth, especially in developing regions.
According to an International Cement Review presentation last fall (pdf), the amount used in the decade spanning 2002–2012 doubled from 1.8 billion tons to 3.7 billion tons. The industry contributes about 5% of anthropogenic CO2 worldwide, and thus gets a lot of attention. However, the industry has been proactively addressing the issue for quite some time. EnvironmentLeader.com reported last summer that statistics from the Cement Sustainability Initiative indicate CO2 emissions since 1990 have dropped from 756 kg/ton to 629 kg/ton—a 17 percent reduction.
Any chance of less concrete being used? Nope.
Karen Scrivener explains in a Chemistry World article (pdf), “The reason there’s so much concrete is because it is in fact a very low impact material.” She says substituting other materials for concrete would only lead to much higher CO2 emissions. “The reason concrete has a big carbon footprint as a whole is that there are just such huge quantities used,” she says. Scrivener leads the construction lab at the Swiss Federal Institute of Technology, Lausanne.
A report from the National Ready Made Concrete Association (pdf) supports Scrivener’s claim, citing data from a study published in the American Concrete Institute Materials Journal. At the time of the study in 1997, production of portland cement consumed one-sixth as much energy as steel. We know the efficiency of both industries has improved significantly in the intervening 17 years, however, the embodied energy of steel still far outpaces concrete.
That does not remove the onus from the concrete industry to lead the effort to reduce its carbon footprint. And, research into alternative, low-carbon cements and alternatives to portland cement comprise a lively, active field of inquiry. Developing low-clinker content cements is a key focus, according to a report from the European Cement Association (pdf).
A group out of Sheffield University in the UK reported recent findings on their work developing clinker-free cements for concrete in the April issue of the Journal of the American Ceramic Society (subscription required, but view abstract here). They call these compounds “alkali-activated materials (AAM),” however, these compounds have been known by many other names, perhaps most famously as “geopolymers.” In the video above, coauthor, SU professor, and ACerS member John Provis summarizes the work and its importance. The lead author is Susan Bernal, a research fellow at SU.
Any substitute for portland cement must be producible throughout the world from a wide range of starting materials. Also, the material properties must be comparable in the fresh state—so that the concrete can be worked with existing tools and skill sets—and in the hardened state.
AAMs result from a reaction between an alkali source and a pozzolanic aluminosilicate precursor, such as blast-furnace slag, fly ash, or calcined kaolinite minerals. The precorsors contain reactive aluminum and silicon, which dissolve under the right alkaline conditions to form a cement-like binder and then rearrange through solution to form a strong dense binding gel.
The authors are careful to note that an all-purpose substitute for portland cement is unlikely. Thus, the chemical and physical properties, that is, the durability of alternative materials, will dictate applications.
The authors report on the gel chemistry and how it varies with calcium content. Also, these materials are “highly spatially heterogeneous,” reflecting inhomogeneity of precursor material particle size, chemistry, mineralogy, and reactivity. That means microstructure, including porosity, dictates properties and must be understood.
The durability discussion in the paper addresses curing, weathering and chemical attack (carbonation), sulfate exposure, and chloride exposure (especially important for steel reinforced concrete).
The authors conclude that “durability of AAMs is strongly dependent on the nano- and microstructure of the reaction products forming in these systems, as a function of the type of precursor, the nature and concentration of the activator, and also the maturity of the material. High-Ca systems have a structure mainly dominated by a C–A–S–H gel, which is less porous than the ‘geopolymer’ gel forming in low-Ca systems. This is one of the main factors controlling the transport properties of AAMs; however, the differences in chemistry of both pore solution and reaction products in AAMs produced with different precursors modify the chemical mechanisms that can lead to the decay of these binders when exposed to aggressive environments.”
They also say, however, that the mechanisms of structural changes need to be better understood before AAMs are used, especially how they interact with different environments. Developing models and tests to predict service life in specific environments will be important for developing AAM cements and making progress toward formulating clinker-free concrete.
The paper is ”Durability of alkali-activated materials: Progress and perspectives,” by Susan A. Bernal and John L. Provis. (DOI: 10.1111/jace.12831).
ACerS members have free access to all of ACerS journals. Learn more about becoming a member.
Featured image above: BSE image and elemental maps of alkali-activated 75 wt% slag/25 wt% fly ash concrete with 28 d curing after 6 months of MgSO4exposure (Courtesy of I. Ismail; JACerS, Wiley.)
Harbison-Walker Refractories Company, an ANH Refractories company, announced the development of a revolutionary refractory mobile application. The first of its kind, the ANH Calculator app is now available through the Apple App Store for the iPhone and iPad, as well as Google Play for Android users, under the name ANH Refractories. This easy to use app will calculate cement kiln brick quantities for both ISO and VDZ shapes. It will determine ring counts and the total net and gross amounts of brick needed for any length kiln section. The app also has a feature that will allows users to call or email a Harbison-Walker representative for more information. The app also offers information on different ANH products and technical bulletins. The available product literature covers kiln brick installation procedures, water addition rates for castables, and information on alkali resistant monolithics.
Morgan Advanced Materials has significantly increased its capabilities at its Wilkes-Barre, Pennsylvania site. This facility manufactures complex injection molded ceramic components for use in the investment casting of turbine engine blades and vanes for aircraft and power generation, aircraft hardware, pumps, valves, and sporting goods. As part of the site’s growth, Morgan has installed advanced equipment that will enable it to produce larger parts for industrial gas turbines (IGTs), hired engineers and managers devoted to increasing production, and implemented communication enhancements to improve tracking, shipping, and delivery. Morgan has invested in capacity and technology to produce IGT cores to meet increasing global power demand. The unique manufacturing process enables shorter lead-times to be offered to customers and provides capability to meet high volume production requirements.
Kyocera has created a new wholly-owned subsidiary, Kyocera Precision Tools, Inc., to consolidate Kyocera Tycom Corp. (KTC) and the cutting tool division of Kyocera Industrial Ceramics Corp. (KICC). This consolidates Kyocera’s North American cutting tool operations in the indexable, micro-tool, and printed circuit board (PCB) cutting tool markets. Kyocera Precision Tools Inc. now carries the company’s full line of micro-tool and PCB cutting tool products, formerly supplied under the name KTC. By July 1, 2014, when the consolidation is completed, the full line of indexable cutting tool products currently supplied by the cutting tool division of KICC will be merged into the new company as well. Kyocera Precision Tools, Inc. is headquartered in Hendersonville, NC. Leading the enterprise as president is Koichi Nosaka, former general manager of cutting tools at KICC, and, as vice president, Jim Good, former president of KTC. All existing cutting tool sales and production facilities will continue to remain operational.
Murata launched a new visual identity that includes changes to the corporate logo and other key visual identity elements. The objective of this initiative is to better express Murata’s philosophy and brand promise – “Innovator in Electronics.” The most visible element of Murata’s brand is the logo, which was created in the 1940′s. It is a well-known symbol that represents the story of a 70-year-old company that has transformed from a small Kyoto-based family business to a global leader in electronics components and solutions. Because of its legacy, changes to the logo are subtle, but very thoughtful and meant to convey Murata’s progressive nature.
United Arab Emirates-based Ras Al Khaimah Ceramics, one of the world’s biggest makers of floor tiles, plans to invest $80 million this year on plant expansions in India and Bangladesh as well as technology upgrades at other plants, its chief executive told Reuters. The company, which makes ceramic wall tiles and sanitary ware as well as floor tiles and is part owned by the ruling family of the emirate of Ras Al Khaimah, posted revenues of 3.5 billion dirhams last year. It is boosting annual production in India to almost 800,000 pieces of sanitary ware from 300,000 to meet rising demand. Besides India, it runs plants in the United Arab Emirates, which accounts for around 70 percent of its overall production capacity, Bangladesh, China, Iran, and Sudan. Its capital expenditure totalled $60 million in 2013. In Bangladesh, RAK Ceramics plans to increase annual capacity by 3.5 million square metres of tiles from the current 7 million, and by 350,000 pieces of sanitary ware from 1 million. The company is also upgrading technology at factories in the UAE and elsewhere.
Published on April 4th, 2014 | Edited By: April Gocha, PhD
Potentially dangerous chemical compounds called polycyclic aromatic hydrocarbons can be reduced in grilled meat, like this tasty number, by simply marinating in beer before cooking, new research says. Credit: Mike; Flickr Creative Commons License.
If the weather is starting to warm where you are, and you’re considering firing up the grill, I may have good news for your weekend—the latest science says go ahead and grab a beer.
Okay, you must be thinking this is a late April Fools’ Day joke—last week I told you it’s okay to go ahead and nosh on chocolate, and now I’m adding beer to the good list, too? No joke—I have the science to prove it. And it may be no coincidence that beer, like chocolate, has a long history with our society.
Typical polycyclic aromatic hydrocarbons, including (clockwise from top left) benz(e)acephenanthrylene, pyrene, and dibenz(ah)anthracene. Credit: Inductiveload; Wikimedia Creative Commons License.
Those previously mentioned dangerous chemicals are polycyclic aromatic hydrocarbons (PAHs), and they have a bad rap for hanging around negative health effects. PAHs are abundant in the environment, atmosphere, and universe, but also in the food we eat. PAHs are particularly prevalent in “smoked and charcoal-grilled products (such as fatty meat and meat products grilled under prolonged or severe conditions),” the authors write in the paper.
(For more PAH info, check out this factsheet (pdf) from the US EPA or this entry in the Toxic Substances Portal from the CDC’s Agency for Toxic Substances & Disease Registry.)
The researchers, a group from Spain and Portugal, smartly married their research interests with their culinary quests and fired up the grill in the name of scientific inquiry. To begin the experiment, they marinated pork loin steaks in beer for four hours in the refrigerator [at a scientific meat–marinade ratio of 1:1 (wt/vol)]. The researchers tested three different beer marinades—light pilsner beer, nonalcoholic pilsner beer, and black beer.
Hooray, dark beer! Credit: Nick Olejniczak; Flickr Creative Commons License.
After marinating, they cooked the meat on a charcoal grill to a well-done internal temperature of 75°C. Although I’m hoping there were at least leftovers for them to enjoy, the authors collected samples of each pork loin, homogenized them, and extracted PAHs. Using liquid chromatography analysis, their results show that marinated meat has reduced levels of total PAHs. Black beer was the winner, as it was able to slash total PAHs in the cooked meat by more than 50 percent.
While the authors admit they’re not yet sure why exactly the marinade works, they did show that black beer by itself can act as an antioxidant to get rid of free radicals (reactive molecules with unpaired electrons), which I take to be good news in its own right. The paper also includes a handy table summarizing previous research on various meat-marinade combos that shows that marinating meat, regardless of the marinade (except for oil alone), can reducing PAHs in cooked meat.
So if you’re a carnivore, crack open a beer, get your marinade ready, and fire up the grill this weekend—and don’t forget the dark chocolate for dessert—just as a toast to your good health.
If you’re unsure which brand to grab and want to follow geographic norms, a new book may be able to help. The Geography of Beer includes a chapter on American beer preferences, broken down by region, that was mined from “beer space” data posted to Twitter.
And speaking of adult beverages, do you know how many bubbles are in the typical glass of champagne? New scientific calculations may give you a surprising answer.
Disclosure: I have no affiliation with nor do I endorse Red Stripe beer—I am just borrowing their tagline!
Published on April 4th, 2014 | Edited By: April Gocha, PhD
Polarized light microscopy reveals that devitrite crystals, grown on heat-treated soda-lime-silica glass, form intricately beautiful fan-shaped needles. Credit: H. Butt, U. of Birmingham.
Haider Butt must believe in the old adage that one man’s trash is another man’s treasure. Butt, a lecturer in microengineering and nanotechnology at the University of Birmingham (United Kingdom), recently discovered a treasure plucked right from the glass industry’s trash.
Although pretty to look at, the overlapping fans of needles of devitrite crystals have long been discarded trash of the glass industry. They used to plague glassmakers who wanted to produce transparent glass, but once they figured out how to keep devitrite at bay, the unwanted but beautiful crystals were mostly put out of sight and out of mind.
Butt’s recent work, published in ACS Nano, details the use of devitrite as a novel optical diffuser. Just how he stumbled upon devitrite, as he explains in an email, is an interesting and funny story.
While training at Cambridge University (United Kingdom), Butt went to the Materials and Metallurgy department to meet a friend. While milling around the reception area waiting for his friend, Butt noticed a poster decorating the department’s walls. The vivid colors of devitrite crystals caught Butt’s eye and seems to have started turning some wheels. Interested and curious, Butt snapped a picture of the poster, met his friend, and moved on.
When he later searched for devitrite online and found a dearth of information about the material’s optical properties, Butt was intrigued. As he explains, “As a researcher, I am always looking for something that has never been done before because I believe that doing something new is easier and involves less work compared to repeating and improving something that has already been done.” Work smarter, not harder.
Hooked by the mysterious intrigue of devitrite, Butt contacted the author of the poster, Kevin Knowles. Knowles, a materials scientist at Cambridge, obliged and provided Butt with some samples of devitrite. Knowles is second author on the ACS Nano paper and also has a paper on the growth of devitrite crystals soon to be published in the Journal of the American Ceramic Society. The paper further characterizes devitrite crystal growth and alleviates some published activation energy discrepancies, and it is entitled “Growth of Devitrite, Na2Ca3Si6O16, in Soda–Lime–Silica Glass” (DOI: 10.1111/jace.12922).
Knowles is quite familiar with the “glass trash,” as he has published a handful of papers to characterize devitrite and its properties. His work shows that although devitrite has long had the status of an unwanted material, ”its crystal growth behaviour from glass, the fine detail of its spherulitic morphology, and the nature of its twinning behaviour…make devitrite a fascinating silicate-based material to continue to study in its own right,” states one of Knowles’ earlier papers. Knowles continues, explaining his original connection to devitrite, in an email:
“The original impetus for this work was the need to have samples some twenty years ago to show the phenomenon of crystal growth for our first year Cambridge undergraduate practicals in Crystalline Materials (as it then was) for the Natural Sciences Tripos. Float glass, when suitably devitrified, turns out to be an excellent material in which to show this as a function of temperature, and our undergraduates still use these samples. The Swift articles from JACerS in 1947 were inspirational in this respect, and I should also acknowledge Kingery, Bowen and Uhlmann who drew my attention to Swift’s work (‘Introduction to Ceramics’, p.356-7). The student who undertook the experiments all those years ago commented on the cloudiness of the devitrified material, but it was Haider who realised that this could be put to good use as a diffuser.”
Observing the striking colors that devitrite crystals reveal under polarized light, Butt realized the discarded stuff must be “doing something interesting with light,” as he says. He and his colleagues went to the lab to induce formation of devitrite crystals in soda-lime-silica float glass by heating at 900°C. They then tested the crystals’ diffusion of a red laser onto a semitransparent hemispherical screen.
Their simple but informative test revealed that devitrite strongly diffuses light at wide angles. The authors write in the paper, “In common with other ceramics and minerals, the refractive indices of devitrite are wavelength-dependent, so that different optical wavelengths undergo different phase retardance.”
Because many current optical diffusers are nanofabricated with sophisticated methods, they are expensive. Devitrite, however, may be able to replace those diffusers because it’s easy to produce at low cost. Potential applications are varied and include optical imaging, photovoltaics, photolithography, and diffusers for thermal energy medical devices, visual display systems, and LEDs, the authors write in the paper.
Butt explains that their research is just beginning. He says in an email, “We already have a commercial partner who is interested in using devitrite as a diffuser for LED light sources in museums. We are also working towards controlled growth of devitrite so that we can control the beam widths of the diffused light.”
As Knowles says in an email, “Haider and I really hope that the interest in devitrite as an optical diffuser will lead to renewed interest in this material.”
Electrospinning is a process for forming long nanofibers using an electric field to elongate and “pull” droplets into fibers.
Besides papers on theory and modeling, and fabrication, conference organizers are looking for papers on applications. In particular, there will be symposia on energy storage, biomedical applications, filtration and textiles, and development of green materials and sustainability. Also, there will be a symposium on polymer nanofibers, as well as one on ceramic and composite nanofibers.
The event includes a poster session, conference dinner, and an optional tour on the afternoon of the third day after the conference closes.
Organizers are scheduling only two to three concurrent sessions, so there will be plenty of opportunity to attend many of the papers. There will be plenty of networking opportunities, too, to meet fellow electrospinners and potential collaborators.
Published on April 2nd, 2014 | Edited By: Jessica McMathis
Analysts anticipate remarkable growth for the wearable technology market, which includes products like the Pebble Smartwatch—crafted with Corning’s Gorilla Glass—pictured above. Credit: Wikipedia.
If 2013 was the year of the “selfie,” then consider 2014 the year of wearable technology.
According to independent analyst firm Canalys, wearables—which include health, sports, and activity trackers, as well as smart-glass products—will become a “key consumer technology” in 2014. The company forecasts that more than 17 million wearable bands will ship in 2014, 23 million in 2015, and more than 45 million by 2017. That’s a lot of wrists.
Those numbers don’t include other wearable technology like Google Glass and smart watches like Samsung’s Galaxy Gear and Apple’s iWatch (possibly featuring the much-buzzed-about sapphire screen), all of which are expected to create their fair share of high-tech hype.
To this point, wearable tech has mostly been limited to activity trackers (i.e., FitBit, which grabbed more than 50 percent of the market share in the second half of 2013, when a whopping 1.6 million smart bands were shipped). But the market, along with the number of early adopters, is expected to balloon, creating a wealth of growth opportunities for those in the lifestyle, fitness, and medical fields.
Among the anticipated applications of wearables:
Surgeons at Washington University School of Medicine are using a special pair of specs that incorporates video technology and a “targeted molecular agent” that can actually “see” cancer.
IBM-subsidiary Fiberlink has developed the MaaS360 program for Google Glass, which allows the wearer to “monitor and influence a mobile IT environment” through the simplest of hand gestures or voice commands.
The Human Condition Institute is developing a “modern” safety vest and hardhat that increase safety conditions for those in construction (i.e., transmits vitals to emergency workers and monitors mundane motions that lead to injury).
The wpForGlass plugin for Google Glass provides “eye publishing,” allowing journalists and bloggers to write and update posts through their eyewear. (This writer, for one, isn’t quite sold on the idea).
It will be interesting to see where new and unique uses of wearable technology might lead both science and consumers (February’s Mobile World Congress, however, served as a pretty good indicator), as well as how the devices might impact issues regarding ethics, privacy, and personal security.
Published on April 2nd, 2014 | Edited By: P. Carlo Ratto
Owens-Illinois, Inc. has completed a €21 million investment at its Leerdam plant in the Netherlands to enhance its capabilities and better support the brewing industry in the Benelux market. O-I’s investment includes a furnace rebuild, machine upgrades and new process and quality equipment to strengthen the plant’s production and quality capabilities.
Saint-Gobain received the decision (pdf) of the General Court of the European Union to reduce the fine imposed by the European Commission in the case concerning the automotive glass industry in Europe for acts dating back to the late 1990s and early 2000s from €880 million to €715 million.
After more than a decade of headlong growth, China is now preparing to focus on consolidating an economic system that favors more equitable distribution of wealth and fosters job development. Double digit growth in GDP is now a distant memory, and China officially closed 2013 at a more modest 7.7%. While apparently excellent by western standards, this was a difficult undertaking for the Chinese economy.
US Steel Corporation wants to make changes to its Fairfield plant and install a new, more efficient electric arc furnace. The company hopes to have the permits approved within the next year and begin building the electric arc furnace in 2015.
ANH Refractories, a nearly 140-year-old manufacturing firm that emerged last year from a 13-year-long Chapter 11 bankruptcy reorganization, will soon move into a new headquarters on the Parkway West in Pittsburgh, Pa. ANH Refractories, which has built a global business with 17 production facilities on three continents, inked a deal to take a 42,000-square-foot office in a new building now under construction at the Pittsburgh International Business Park. The new location is within walking distance of ANH’s current 62,000-square-foot office at Cherrington Corporate Center in Moon Township.
Now, new information from researchers at Arizona State University (ASU) is uncovering just how effective urban adaptation technologies like these cool roofs—or their green (“vegetated”) counterparts—are at curbing climate change.
Their work reveals that US urban sprawl alone (i.e., none of the global warming caused by harmful greenhouse gases) increases surface temperatures by three degrees Celsius (or close to six degrees Fahrenheit). Urban adaptation technologies can, they say, counteract this climate change, though the degree (pun intended) varies depending on the season and geography.
In their paper titled “Urban adaptation can roll back warming of emerging megapolitan regions,” the ASU team, led by Matei Georgescu, pinpoints how technologies like cool roofs hold up to the various geographies and climates of the 50 states.
“This is the first time all of these approaches have been examined across various climates and geographies,” said Georgescu in an ASU press release. “We looked at each adaptation strategy and their impacts across all seasons, and we quantified consequences that extend to hydrology (rainfall), climate, and energy. We found geography matters.”
It certainly mattered in the south, where their simulations revealed an additional and adverse effect on Florida’s ecosystem.
According to Georgescu, “The deployment of cool roofs results in a 2 to 4 millimeter per day reduction in rainfall, a considerable amount (nearly 50 percent) that will have implications for water availability, reduced stream flow, and negative consequences for ecosystems. For Florida, cool roofs may not be the optimal way to battle the urban heat island because of these unintended consequences.”
More generally speaking, the ASU study found cool roofs to be of great benefit during summer, cooling buildings and lessening the demand for energy. In winter, however, those same roofs, particularly those in the north, were a little too effective—cooling buildings to the point where additional heating was necessary. Conversely, green roofs—more transpiring than reflective—don’t provide the level of cooling during the summer months, nor do they necessitate greater demand in winter.
Because of the differences in both demand and geography, researchers suggest that both the construction industry and consumers alike should be proactive in combatting continued climate change through “judicious planning and design choices.”
Feature image credit: xnatedawgx on Wikimedia Commons.
ARPA-E is accepting applications for Fellows and Technology-to-Market Scholars. During their two-year tenure, ARPA-E Fellows identify breakthrough energy technologies and white spaces. During their 8-12 week tenure, ARPA-E Technology-to-Market Scholars conduct analysis and research to support the commercialization of ARPA-E’s high-impact energy technology projects and programs. Application requirements and instructions for both programs can be viewed in the Job Opportunities section of the ARPA-E website. The deadline to apply for Fellows positions is Friday, April 11. Technology-to-Market Scholars applications are due Friday, April 4.
University of Utah electrical engineers led byprofessor Massood Tabib-Azar fabricated the smallest plasma transistors that can withstand high temperatures and ionizing radiation found in a nuclear reactor. Such transistors someday might enable smartphones that take and collect medical X-rays on a battlefield, and devices to measure air quality in real time. The new devices designed by the University of Utah engineers are the smallest microscale plasma transistors to date. They measure 1 micron to 6 microns in length, or as much as 500 times smaller than current state-of-the-art microplasma devices, and operate at one-sixth the voltage. They also can operate at temperatures up to 1,450 degrees Fahrenheit. Unlike typical transistors, the Utah microplasma transistor “channel” is an air gap that conducts ions and electrons from the plasma once a voltage is applied. To achieve this unique design, the team etched away portions of the silicon film using a chemically reactive gas. This etching process leaves behind cavities and empty spaces to form the transistor’s channel and expose the gate underneath. The channel tested in this new study was 2 microns wide and 10 microns long, and helium was used as the plasma source.
By slowing and absorbing certain wavelengths of light, engineers open new possibilities in solar power, thermal energy recycling and stealth technology. More efficient photovoltaic cells. Improved radar and stealth technology. A new way to recycle waste heat generated by machines into energy. All may be possible due to breakthrough photonics research at the University at Buffalo. The work, published March 28 in the journal Scientific Reports, explores the use of a nanoscale microchip component called a “multilayered waveguide taper array” that improves the chip’s ability to trap and absorb light. Unlike current chips, the waveguide tapers (the thimble-shaped structures above) slow and ultimately absorb each frequency of light at different places vertically to catch a “rainbow” of wavelengths, or broadband light. Each multilayered waveguide taper is made of ultrathin layers of metal, semiconductors and/or insulators. The tapers absorb light in metal dielectric layer pairs, the so-called hyperbolic metamaterial. By adjusting the thickness of the layers and other geometric parameters, the tapers can be tuned to different frequencies including visible, near-infrared, mid-infrared, terahertz and microwaves.
Polymer materials are usually thermal insulators. But by harnessing an electropolymerization process to produce aligned arrays of polymer nanofibers, researchers have developed a thermal interface material able to conduct heat 20 times better than the original polymer. The modified material can reliably operate at temperatures of up to 200 degrees Celsius. The new thermal interface material could be used to draw heat away from electronic devices in servers, automobiles, high-brightness LEDs and certain mobile devices. The material is fabricated on heat sinks and heat spreaders and adheres well to devices, potentially avoiding the reliability challenges caused by differential expansion in other thermally-conducting materials.
Medical engineers have created a device the size of a bandaid that monitors patients by tracking their muscle activity before administering their medication. Methods for monitoring so-called “movement disorders” such as epilepsy and Parkinson’s disease have traditionally included video recordings or wearable devices, but these tend to be bulky and inflexible. The new gadget, which is worn on the skin, looks like a Band-Aid but uses nanotechnology to monitor the patients. Scientists have long hoped to create an unobtrusive device able to capture and store medical information as well as administer drugs in response to the data. This has proved difficult due to the large amount of onboard electronics and storage space required, high power consumption, and the lack of a mechanism for delivering medicine via the skin. Now, a team from South Korea and the United States have used nanomaterials to create a flexible and stretchable device that resembles an adhesive plaster, about one millimeter thick. The device comprises multiple layers of ultrathin nanomembranes and nanoparticles and is worn on the wrist. The recorded data then triggered the release of drugs stored inside the nanoparticleswith the aid of a wafer-thin internal heater.
An extremely tiny lensless camera, developed by Rambus, has been slowly making waves over the past year. Researchers for the company, David Stork and Patrick Gill won a Best Paper award at last year’s Sencomm 2013 for describing their new type of camera—one that might someday soon be used to give virtually any digital device, some degree of vision. The camera is both simple and complex, it’s really just a very tiny chip (CMOS imager) embedded in a piece of glass. Instead of a lens, a pattern is etched into the glass above the chip—the imager reads the light that is received, processes it using an algorithm developed by Rambus and converts it into a recognizable image. What’s amazing is that the etched pattern on the glass and the chip are both roughly the size of a period at the end of a sentence. Particular etched patterns allow for light to be intentionally refracted in different ways as it passes through the glass—images made from them would appear unrecognizable to the human eye, but the algorithm makes use of refraction properties to reconstruct the light received into a recognizable image.