Atomic force microscope image of 50-nm diameter silica nanoparticles on PTFE surface. Researchers at the University of Arkansas found that relatively low concentrations of the particles greatly improved PTFE wear resistance. Credit: M. Zou, University of Arkansas
Well known as a nonstick surface in applications from kitchen tools to aerospace and medical components, polytetrafluoroethylene (Teflon) is getting a boost in wear resistance thanks to silica nanoparticles.
According to this press release, researchers at the University of Arkansas (Fayetteville) treated PTFE films with silica nanoparticles to significantly reduce wear while maintaining low friction in tests.
In a comparison of PTFE surfaces impregnated with silica nanoparticles versus pure PTFE films and bare stainless steel, the researchers found the composite films had greatly improved wear characteristics. All PTFE coatings were produced by dip coating type 316 stainless steel substrates.
According to researcher Min Zou, associate professor, director of the university’s Nano Mechanics and Tribology Laboratory (NMTL), and holder of the 21st Century Professorship in Mechanical Engineering, workers tested PTFE surfaces with two concentrations of 50-nm diameter silica nanoparticles—1.7 and 3.3 wt.%—against a conventional PTFE surface and bare stainless steel.
“Linear reciprocating wear tests were performed by repetitively rubbing the test samples against a chrome steel ball under an applied pressure up to 0.5 GPa,” Zou explained in an e-mail message. “The pure PTFE film failed immediately under 0.5 GPa pressure, while the composite film with 3.3 wt.% silica lasted 300 cycles.”
Results of the initial study were published in Tribology Transactions, a journal of the Society of Tribologists and Lubrication Engineers (Park Ridge, Ill.). The paper received the Society’s Al Sonntag Award for the best paper published on solid lubricants.
Zou and her team have continued their research with further development of the silica–PTFE composite material as well as testing of other types of nanoparticles in thin PTFE coatings, she reports. “The durability of the film has been increased four times compared to what we reported in this paper. If adding an adhesive layer, durability is increased 70 times. “
NMTL has developed a variety of nanoengineered surfaces (NESs), which are engineered with nanoscale topographies and chemistries to reduce friction and wear in tribological applications, change wetting properties of surfaces for anti-fogging and self-cleaning properties, and facilitate cell adhesion and growth in biomedical applications. Zou welcomes collaborative opportunities on novel methods of fabrication, characterization, and applications of NESs.
Owens Corning and Constellation today announced the development of a 2.6-megawatt solar generation project that will supply clean energy to the company’s thermal and acoustical insulation plant in Delmar, N.Y. Scheduled for completion in late 2013, the solar project is designed to supply more than 6 percent of the plant’s annual electricity needs and will support Owens Corning’s 2020 Environmental Footprint Goals for energy use and greenhouse gas emissions reduction. “The Delmar Plant is committed to environmental sustainability and advancing both our plant and Owens Corning toward our 2020 sustainability goals,” says John Becker, Delmar plant leader for Owens Corning. “In addition, this project is part of our continuing efforts to implement innovative programs that improve and protect New York State’s environment, and have a positive impact on the state’s economy.” Constellation will finance, build, own and maintain the system. Electricity generated by the system will be purchased by Owens Corning under a 20-year power purchase agreement with Constellation.
A recently added market report by Transparency Market Research on “Energy Efficient Materials Market—Global Industry Size, Share, Trends, Analysis And Forecasts 2012-2018″ is now available. Energy efficient materials are largely used for thermal insulation of buildings as a result of which, demand for these materials is on the rise. Thermal insulation is the most efficient and effective way to improve the energy utilization and efficiency in the building. This method will preserve the indoor heat during winter while keeping the building cool from inside in summers thus improving comfort and saving energy. Some important factors which are necessary for energy saving potential include thermal insulation, efficient lighting system, insulation of windows etc. The most common energy efficient material is fiber glass which is largely used in constructing energy efficient windows. Energy efficient materials industry has a huge market potential in developed countries of America and Europe however, this technology is expected to catch momentum in developing markets of Asia Pacific in near future owing to the increasing adoption of the concept of energy efficient homes. Energy efficient materials market is also driven by increasing consumer demand for operating various appliances and increasing standard of living. In America about 38 percent of total energy consumption is used for heating and cooling purpose in buildings while China accounts for 47.2 percent of total energy consumption.
U.S. Silica exceeded all of its 2012 Sustainability Targets including those for workplace safety, community investment and environmental protection. The company released its third annual Sustainability Report, Connected, which provides a summary of the company’s goals and accomplishments over the past year. Under the guidance of the company’s Sustainability Council, the 2017 Bold Goals and Annual Targets are focused on three distinct areas: People, Planet and Prosperity. Building off of the company’s last two reports, Connected reflects U.S. Silica’s commitment to employees, neighbors, shareholders and the natural environment. It also underscores U.S. Silica’s leadership in sustainability efforts, ranging from tree plantings and wildlife preservation initiatives to financial and in-kind support for local charities and outreach groups.
(Reuters News) From whitewares to solar panels, ceramic products imported from China are about to become much more expensive for European consumers after the European Commission agreed to impose punitive duties on Chinese ceramic imports to counter what it says is dumping at artificially low prices. Imported Chinese whitewares are now subject to tariffs of between 13.1 and 36.1 percent, according to the EU’s official journal. The European Commission says ceramic tableware and kitchenware imports from China totaled €728 million in 2011. After an investigation of alleged dumping by Chinese producers of €21 billion of solar panels and components, the commission also imposed punitive tariffs of 47 percent on Chinese solar goods and said it is also ready to launch an investigation into Chinese imports of mobile telecom equipment.
Growth in industrial markets, more regulations and a shortage of skilled metallurgists all mean the same to NSL Analytical Services Inc.: more business. The independent commercial testing company recently invested more than $1.6 million to buy and renovate a new metallurgical laboratory in Warrensville Heights, Ohio, thus expanding that component of its business. At 11,500 square feet, the new building offers more than double the space of its old metallurgical lab, with more than $560,000 of that investment going to new microscopes, testing machines and other equipment. NSL Analytical, made up of a chemical testing lab and a metallurgical lab, has embarked on an aggressive growth plan in recent years, doubling its revenues and adding 17 employees since 2007, says company president Larry Somrack. He declined to share the company’s annual revenues, but cited the hiring increase as a sign of success. NSL is setting itself up to double its revenue again during the next three years, and Somrack says he plans to hire another 19 employees in the next three to five years. NSL currently has 66 employees. Somrack thinks opportunities exist to support that growth. A rise in regulations in recent years has led to a greater need for outside testing. Also, chief metallurgist Kevin Holland says in an email that he’s seen growth in the oil and gas industry and in manufacturing since the end of the recession.
After spending years supporting charitable work in Africa, John Coors, chief executive of CoorsTek, the US ceramics manufacturing giant, reached the conclusion that philanthropy was not the answer to fostering economic development. A defining moment came in rural western Kenya about two years ago, when he and a team of doctors and dentists had to turn away lines of people seeking medical help at an orphanage they supported because they could not meet the demand. High quality global journalism requires investment. The experience was the catalyst for Mr Coors to come up with an alternative view, shifting from a charitable approach to capitalism. The result is an initiative that aims to attract investment from influential, wealthy families into a private equity-type fund that has an initial target of raising $300m to invest in sub-Saharan Africa. The One Thousand & One Voices (1K1V) project was launched at the World Economic Forum on Africa in Cape Town with the concept that money would be put to better use if it was invested in growing African businesses and boosting job creation.
3M reports first-quarter earnings of $1.61 per share, an increase of 1.3 percent versus the first quarter of 2012. Sales rose 2.0 percent year-on-year to $7.6 billion, an all-time first-quarter record. Organic local-currency sales grew 2.1 percent and acquisitions added 1.7 percent to sales. Currency impacts reduced sales by 1.8 percent year-on-year. Operating income was $1.6 billion and operating income margins for the quarter were 21.6 percent. First-quarter net income was $1.1 billion and free cash flow was $670 million. “We achieved record first-quarter sales and solid operating margins in the face of a low-growth economic environment and the strong U.S. dollar,” said Inge G. Thulin, 3M chair, president and chief executive officer. “At the same time, we further strengthened the company through increased investments in innovation, commercialization and manufacturing.” The company paid $440 million in cash dividends to shareholders and repurchased $805 million of its own shares during the quarter.
Recent innovations in LEDs have improved the energy efficiency of streetlights, but, until now, their glow still wastefully radiated beyond the intended area. A team of researchers from Taiwan and Mexico has developed a new lighting system design that harnesses high-efficiency LEDs and ensures they shine only where they’re needed, sparing surrounding homes and the evening sky from unwanted illumination. The team reported their findings in the open-access journal Optics Express. The proposed lamp is based on a novel three-part lighting fixture. The first part contains a cluster of LEDs, each of which is fitted with a special lens, called a Total Internal Reflection lens, that focuses the light so the rays are parallel to one another instead of intersecting. These lens-covered LEDs are mounted inside a reflecting cavity, which “recycles” the light and ensures that as much of it as possible is used to illuminate the target. Finally, as the light leaves the lamp it passes through a diffuser or filter that cuts down on unwanted glare. The combination of collimation and filtering also allows researchers to control the beam’s shape: the present design yields a rectangular light pattern ideally suited for street lighting, the researchers say. In addition to cutting light pollution and glare, the new model could also save energy. A general LED street light could reduce power consumption by 40 to 60 percent. The increased efficiency of the proposed design would likely save an additional 10 to 50 percent. Furthermore, the module would be simple to fabricate, since it comprises just four parts, including a type of LED bulb commonly used in the lighting industry.
The union of theory and practice makes broadband, low-loss optical devices practical, which is why two groups of Penn State engineers collaborated to design optical metamaterials that have custom applications that are easily manufactured. In the past, to control the optics of metamaterials, researchers used complicated structures including 3-dimensional rings and spirals that are difficult if not impossible to manufacture in large numbers and small sizes at optical wavelengths. From a practical perspective, simple and manufacturable nanostructures are necessary for creating high-performance devices. ”We must design nanostructures that can be fabricated,” says Theresa S. Mayer, Distinguished Professor of Electrical Engineering and co-director of Penn State’s nanofabrication laboratory. Designing materials that can allow a range of wavelengths to pass through while blocking other wavelengths is far more difficult than simply creating something that will transmit a single frequency. Minimizing the time domain distortion of the signal over a range of wavelengths is necessary, and the material also must be low loss. The design team looked at existing fishnet structured metamaterials and applied nature-inspired optimization techniques based on genetic algorithms. They optimized the dimensions of features such as the size of the fishnet and the thicknesses of the materials. One of the transformative innovations made by the researchers was the inclusion of nanonotches in the corners of the fishnet holes, creating a pattern that could be tuned to shape the dispersion over large bandwidths.
University of Nebraska-Lincoln materials engineers have developed a structural nanofiber that is both strong and tough, a discovery that could transform everything from airplanes and bridges to body armor and bicycles. Their findings are featured on the cover of the American Chemical Society’s journal, ACS Nano. “Our discovery adds a new material class to the very select current family of materials with demonstrated simultaneously high strength and toughness,” says the team’s leader, Yuris Dzenis, McBroom Professor of Mechanical and Materials Engineering and a member of UNL’s Nebraska Center for Materials and Nanoscience. Dzenis and colleagues developed an exceptionally thin polyacrilonitrile nanofiber, a type of synthetic polymer related to acrylic, using electrospinning. Dzenis suggests that toughness comes from the nanofibers’ low crystallinity. In other words, it has many areas that are structurally unorganized. These amorphous regions allow the molecular chains to slip around more, giving them the ability to absorb more energy.
Resistive memory cells (ReRAM) are regarded as a promising solution for future generations of computer memories. They will dramatically reduce the energy consumption of modern IT systems while significantly increasing their performance. Unlike the building blocks of conventional hard disk drives and memories, these novel memory cells are not purely passive components but must be regarded as tiny batteries. This has been demonstrated by researchers of Jülich Aachen Research Alliance. The new finding radically revises the current theory and opens up possibilities for further applications. The research group has already filed a patent application for their first idea on how to improve data readout with the aid of battery voltage. In complex experiments, the scientists from Forschungszentrum Jülich and RWTH Aachen University determined the battery voltage of typical representatives of ReRAM cells and compared them with theoretical values. This comparison revealed other properties (such as ionic resistance) that were previously neither known nor accessible.”The demonstrated internal battery voltage of ReRAM elements clearly violates the mathematical construct of the memristor theory. This theory must be expanded to a whole new theory–to properly describe the ReRAM elements,” says Eike Linn, a specialist for circuit concepts.
(Berkeley National Lab/YouTube) A worldwide race is on for scientists to develop ever more powerful X-ray microscopes. With ultra-high resolution X-ray optics at ultra-bright synchrotrons—such as the 120-meter-long Hard X-Ray Nanoprobe (HXN) being developed for the National Synchrotron Light Source II (NSLS-II) at Brookhaven Lab—researchers will see structure and chemistry deep inside natural and engineered materials as they address some of the biggest questions in materials science, physics, chemistry, environmental sciences, and biology. Unprecedented capabilities, however, bring critical technical challenges, but scientists at Brookhaven Lab are on the job. In this video of the 486th Brookhaven Lecture, Yong Chu illustrates unique challenges and innovative approaches for X-ray microscopy at the nanoscale. He also discusses measurement capabilities for the first science experiments at NSLS-II. Chu joined the Photon Sciences Directorate at Brookhaven Lab as group leader for the HXN beamline at NSLS-II in 2009.
The innovative research of a Montana State University student, Neerja Zambare, a senior from Pune, India, majoring in both chemical engineering and biological engineering, was selected as one of the country’s undergraduate researchers for her poster about a bio-cement that effectively plugs cracks near wells and drilling sites. Zambare exhibited her research poster, “Biofilm induced biomineralization in a radial flow reactor,” at the Council on Undergraduate Research’s Posters on the Hill Exhibition April 23-24 in Washington, D.C., one of the country’s most prestigious undergraduate research fairs. Zambare was accompanied by Robin Gerlach, MSU professor of chemical and biological engineering and Zambare’s research mentor. Gerlach said Zambare convinced him that she would be the right person to join his lab group in the Center for Biofilm Engineering. The group trained her and then asked her to join a project that the lab had been working on for some time—a bacterium that makes calcium carbonate and has potential applications in sealing ponds, plugging cracks emitting carbon dioxide near carbon sequestration wells as well as abandoned wells.
(arXiv) Two modifications have been made to a miniature ceramic anvil high pressure cell (mCAC) designed for magnetic measurements at pressures up to 12.6 GPa in a commercial superconducting quantum interference (SQUID) magnetometer. Replacing the Cu-Be piston in the former mCAC with a composite piston composed of the Cu-Be and ceramic cylinders reduces the background magnetization significantly smaller at low temperatures, enabling more precise magnetic measurements at low temperatures. A second modification to the mCAC is the utilization of a ceramic anvil with a hollow in the center of the culet surface. High pressures up to 5 GPa were generated with the “cupped ceramic anvil” with the culet size of 1.0 mm.
As nanotechnology is increasingly commercialized, the question of safety, as it relates to handling the materials during synthesis and manufacture, and even in product use, arises regularly.
The National Institute for Occupational Safety and Health (NIOSH), a branch of the Centers for Disease Control and Prevention, has the issue on their radar. According to its website, NIOSH has identified 10 critical areas that it wants to “guide in addressing knowledge gaps, developing strategies, and providing recommendations,” and it is backing it up with research on the nanomaterials in the workplace. The 10 areas are toxicity and internal dose; risk assessment; epidemiology and surveillance; engineering controls and personal protective equipment; measure methods; exposure assessment; fire and explosion safety; recommendations and guidance; communication and information; and applications.
A big problem is that it is not easy to observe how nanoparticles interact with human physiology, in part because they are so small and, because of this, analytical techniques are difficult to develop. For example, a while back we reported on research on whether zinc oxide nanoparticles in sunscreen might be a health hazard. In this work, investigators used nonlinear optical microscopy to directly measure ZnO nanoparticle uptake in the deep layers of human skin-those that underlie the stratum corneum surface layer.
This week, the American Chemical Society (ACS) is holding its 245th national meeting (congratulations, ACS!) in New Orleans. This year’s theme—Chemistry of Energy and Food—explores the relationship, of course, between chemistry and food. This year is the first year for a new ACS lecture, the Kavli Foundation Emerging Leader in Chemistry Lecture. The lecture, delivered on Monday by Christy Haynes of the University of Minnesota, was titled “Biological and ecological toxicity of engineered nanomaterials.” According to the ACS website, Haynes is among the first to use a specialized technique to study the effect of nanoparticles on cells called “carbon-fiber microelectrode amperometry,” which is used in medicine to study sickle cell anemia, endocrine chemistry, etc.
According to an ACS press release, Haynes says more than 800 consumer products involve nanotechnology and has given rise to the new field of “nanotoxicology.” Initially, she said in her lecture, attempts were made to infer nanotoxic effects based on analytical tests developed for bulk materials. However, as is known now, nanoparticles behave very differently from bulk particles—and not just in the body. The interest in nanoparticles as engineered materials for things like supercapacitors derives from their unique size-related properties.
Haynes said in her lecture, “a nanoparticle of material used in food or a cosmetic lotion may contain just a few atoms, or a few thousand atoms. Regular-sized pieces of that same material might contain billions of atoms. That difference makes nanoparticles behave differently than their bulk counterparts.”
Early toxicology tests, she said, were simple: Did cells growing in a laboratory culture live or die after being exposed to a nanoparticle? However, such a simple approach did not account for two important factors. First, Haynes said, “A cell can be alive but unable to function properly, and it would not be apparent in those tests. Second, nanoparticles are more highly reactive (again, an attractive, “engineerable” property), which can cause “false positives” and make nanoparticles appear more toxic than they are.
Researchers in Haynes’ lab are working on tests to determine whether “key cells in the immune system can still work normally after exposure to nanoparticles.” Also, they are using bacteria to probe whether cells exposed to nanoparticles can maintain the “biochemical chatter” that is essential.
Haynes leads the University of Minnesota’s contribution to the multi-institutional, NSF-funded Center for Sustainable Nanotechnology. Located at the University of Wisconsin-Madison, the center is “devoted to investigating the fundamental molecular mechanisms by which nanoparticles interact with biological systems.”
David Willetts’ speech on the eight-part strategic technology roadmap for the UK. Credit EPSRC.
The United Kingdom’s Engineering and Physical Sciences Research Council (EPSRC) announced that seeks proposals to fund with a total of £85 million (approximately $120 million) aimed at increasing the nation’s research base related to three technologies:
- Advanced Materials (£30 million)
- Grid-scale Energy Storage (£30 million)
- Robotics & Autonomous Systems (£25 million)
An advocate for the funding has been David Willetts, the UK’s minister for universities and science. A report and speech (above) by Willetts in January of this year called for research in “eight great technologies.” Three of the eight are included in this funding announcement. Willetts says in a news release, “This £85 million capital fund will boost our research capability in advanced materials, energy storage, and robotics and autonomous systems. It will keep the UK at the forefront of science and innovation.”
David Delpy, the EPSRC’s chief executive, also notes in the release, “The work will help develop new ways of storing power, new materials that can aid manufacturing and other industries, and further developing how autonomous systems communicate, learn and work with humans.”
The EPSRC is somewhat analogous to the United States’ National Science Foundation and is the UK’s main agency for funding research in engineering and the physical sciences. It has a budget of around £800 million per year that it invests in research and postgraduate training.
In a detailed call for proposals (pdf), the EPSRC warns that it is not interested in creating new centers and will not accept proposals unless the application is from an institution or a collaboration that has successfully attracted at least £10m of research funding from any source over the past five years (April 2008-March 2013) within the relevant technology area. In addition, the call says applicants will be required to show existing significant support from EPSRC as well as evidence of a substantial financial contribution to the equipment procurement and to the potential to sustain the research.
Further, the EPSRC says individual awards are expected to be in the region of £3 million, however, it also notes that larger bids are encouraged if the applicants have a strong case that “justifies the benefit of this level of investment, if the institution contribution is significant, or if a joint bid is being made by a group of institutions.”
In regard to advanced materials funding, the call describes the EPSRC’s interest as follows:
Advanced materials are instrumental in the generation of long-term economic growth and jobs for the UK and reducing the time required to bring discoveries to the market has been recognized by global competitors in being a key driving force behind a more competitive manufacturing sector and economic growth. Focus should be on materials designed for targeted properties and on seeking to address the aims of this initiative, i.e., reducing lead times, tackling sustainability of materials and discovering new materials types.
The pervasive nature of materials and their application into countless different sectors presents simultaneously both an opportunity and a challenge. Whilst all material areas are included here, we can identify a small number of materials candidates as particular priorities offering the greatest potential to lead to new market opportunities or underpin the competitiveness of high value existing sectors. These include Advanced Composites, Low Energy Electronics (including metamaterials), Materials for Energy, High Performance Alloys, and Nanomaterials for Health.
The main objectives of the call are to:
• Invest in the development and provision of scale-up facilities, including innovative production technologies in advanced manufacturing such as advanced metrology, flow production, laser processing systems, resource efficient technologies, and multifunctional additive layer manufacturing including modeling;
• Invest in characterization of materials at the nanoscale (e.g., atomic force microscopy, scanning electron microscopy).
The deadline for submitting proposals is May 16, 2013, and the call has quite a few more details about the contents of the applications.
A total of £73 million eventually is to be targeted for advanced materials. Besides advanced materials, grid/energy technologies, and robotics, the other five technologies Willetts identifies are big data, space, synthetic biology, regenerative medicine, agri-science.