A BBC video imagines a Masters golf tournament with putt-putt hazards. Credit: BBC; You Tube.

What I know about golf would not fit inside the head of a putter. In fact, the only club I can name is the putter because it’s also used to play miniature golf, a game that I enjoy but excel at failing.

I must not be alone, because the BBC recently imagined what a “major mini” might look like, that is, what if the US Open or other major golf tournament were played in putt-putt format? This video I can relate to!

Also on the subject of golf, I came across this brief radio broadcast on the National Academy of Engineering’s website about biodegradable golf balls made from lobster shells. University of Maine (where else?) professor, David Neivandt, grinds the shells into powder and mixes it with a biodegradable polymer binder to make the core. The core is coated with another ecofriendly material and a ball is born.

Aside from traditional golf course water hazards, Neivandt suggests the lobster balls would be useful, for example, on cruise ship driving ranges.

In the broadcast, Neivandt says, “In a period of a week or two weeks or so the entire ball breaks down and releases the lobster back into the ocean.”

Hey Peter - I’ll be taking some time off soon to run some experiments in the Caribbean on those golf balls. I should be able to pop one into the ocean.

Hat tip to Kent Anderson and The Scholarly Kitchen.

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Materials engineering will drive development of the next generation of energy efficient vehicles. Credit: Wikipedia.

News is ubiquitous about efforts and advances in the realm of energy, often in the context of transportation, environmental impact and efficiency. Just yesterday, for example, President Obama announced $14.2 million in new DOE funding to develop lightweight materials for advance materials. According to the press release, a 10 percent weight reduction can improve fuel economy by six to eight percent.

Don’t get too excited, though. The new funding will support three specific materials research areas, none of which include ceramic materials:

1. Predictive modeling of carbon fiber composites
2. Predictive modeling of advanced steels
3. Advanced alloy development for automotive and heavy-duty engines.

We know, however, that ceramic materials have properties that are unique, making them critical contributors to engineered systems of materials. But, ceramic materials are subtle; you have to know what you are doing, especially when used in sophisticated applications.

It is no wonder, then, that the Energy, Environment and Transportation track of the 4th International Congress on Ceramics has attracted the largest number of participants. Kevin Fox, of Savannah River National Lab, led the technical programming committee for this track. He says, “Ceramics will be highlighted as the enabling technology for clean and renewable energy production, environmental stewardship, and efficient transportation.”

The triple-themed track covers a lot of ground and addresses issues that are global. Recognizing this, Fox said the programming committee “carefully coordinated the themes [energy, environment, transportation] to reflect the cross-cutting impact of ceramic materials in these topical areas. Representatives from across the globe will provide presentations on the current and future influence of ceramics in these areas, as well as focused accounts of leading edge developments for specific applications.”

Here is a sampling from the ICC4 Energy, Environment and Transportation track. Profiles of invited speakers in the track can be seen on the website. ICC4 is July 15-19 in Chicago.

ENERGY
The Unique Role of Ceramics in Energy Technologies: Recent Developments and Opportunities
Juan Nino, University of Florida

This talk start with an overview of the unique role that ceramic materials currently play in energy related technologies (chemical, electrical, and nuclear). It will be followed by a summary of recent critical material developments in several areas including fuel cells, batteries and ultracapacitors, the opportunities that these advancements enable and a path to realization will be highlighted. In addition, the essential role that ceramics can play in transitioning from fossil and radioactive energy sources towards a sustainable energy landscape will be emphasized. In particular, ceramic solutions to current materials needs in proton conductors and the nuclear fuel cycle will be presented. The talk will then transition towards the role of ceramics in sustainable electrical energy generation such as thermoelectric and piezoelectric energy harvesting. Finally, the challenge to scientists and engineers from industry, government and academia to realize these opportunities will be discussed.

Change of Energy Mix — Challenges on the Materials Level
Wolfgang Rossner, Siemens AG

Sufficient, safe and sustainable generation of energy is an essential key factor for our future global development. The continuous growth of the global population, the progress of industrialization and the increasing urbanization are the main sources for the continuously increasing demand for energy and electric power in particular. To master these challenges and in consideration of the global situation of ‘fuel’ resources, environmental safety and climate change the overall energy mix has started to change. The predominance of fossil and nuclear energy is losing ground while renewable and ‘green’ energy are increasing their contribution. Nevertheless, the change of energy mix has to provide the highest efficiency levels and the lowest emission levels in a holistic evaluation. In consequence this translates to continuous performance improvements of both conventional and renewable power generation. In many cases this is related to the progress of materials performance. High temperature alloys and ceramics in gas turbines or functional coatings and heat transfer materials in solar thermal power plants are just a few examples. Several scenarios will be discussed with respect to the potential of novel and advanced materials to create substantial impact on the future energy mix as well as the challenges where advanced ceramics seem to be predestined to provide progress.

ENVIRONMENT
Future of Porous Ceramics in Environmental, Energy and Related Applications
Paolo Colombo, University of Padova

Highly porous ceramics are key enabling components for a wide variety of engineering applications, in fields ranging from medicine to the environment, from transportation to energy, from aerospace to defense. The ability to tailor the architecture of the porosity, such as its amount, the pore size, shape and interconnectivity, down to the nano-scale through advanced processing techniques allows researchers and engineers to select the most appropriate set of properties to match the specific requirements of the application. For instance, global environmental concerns over the presence of nano-sized particulate in various environments are prompting researchers to investigate more effective and affordable filters to be used, for example, for the abatement of mobile and stationary diesel emissions, air conditioning, indoor pollution control or individual protection equipments. Typical macro-porous ceramics, in particular ceramic foams, have a low collection efficiency for small dust particles, although they have been extensively used in solid-fluid contact processes in which good fluid mixing degree, increased mass transfer rates and low pressure drop are simultaneously required. A novel development consists in the in-situ growth of nano-wires on the surface of commercially available porous ceramics, via a low cost, effective and versatile method. Porous ceramics play also a vital role in energy generation and storage as catalyst supports, adsorbers, membranes, thermal protection and insulation components; novel processing methods, such as stabilization of foamed slurries via ceramic particles, enable to fabricate large parts in a very wide range of densities, including ultralight components possessing high mechanical strength, therefore extending the range of applications and working conditions in which they can be used. This talk will review the state of the art porous ceramics used in different strategic technological fields, such as environmental management, energy production and storage, and will point out the most promising developments.

Sustainable concrete
Andreas Tselebidis, BASF Corp.

Environmental policy and sustainability are core issues within the concrete construction industry. Producers and contractors are increasingly being expected to preserve natural resources while continuing to produce quality products, and thus are searching for construction methods, practices, and products that will promote these objectives. The shift to an environmentally conscious marketplace requires the innovative development of products, practices and procedures. A new, advanced optimization process for concrete mixes, with its main focus on the Nano scale in materials, allows concrete producers to proportion concrete in a new and revolutionary way that achieves new levels of performance, economics and sustainability. This process utilizes optimized proportions of supplementary cementitious materials, non-cementitious fillers, or both, used with special tailored chemical admixtures to meet or exceed performance targets. The understanding of interactions and material properties at the Nano scale allows manipulating and controlling material characteristics at the macro scale. The result are desired concrete properties in the fresh or hardened state that are met without compromising currently accepted practices while improving the state of the art in concrete technology. This presentation will provide an overview of the advanced mix optimization process. In addition, the presentation will illustrate the use of an Eco-Efficiency Analysis methodology to measure the sustainability of concrete. he results of this analysis allows the comparison of different concrete mixes to enable concrete technologists, scientists, engineers and specifiers to choose a concrete mix with the lowest environmental impact for a project.

TRANSPORTATION
Micron-Scale Tunable Acicular Mullite Ceramics for Filtration Applications
Jim O’Brien, Dow Chemical Company

Acicular mullite (ACM) is a breakthrough, disruptive technology platform for ceramic materials science. The interconnected needle morphology and composition of the ACM microstructure enables this material to exhibit outstanding physical properties and performance attributes that are impossible with conventional ceramics, including high strength, melting temperature, chemical stability, porosity, permeability, and tunable pore size. As such, ACM is an ideal candidate material for numerous high performance applications, particularly filtration and catalysis. By controlling the processing conditions used to produce ACM, the acicular microstructure can be easily tuned at the micron-scale to optimize both porosity and pore size for a particular application. For example, a single ceramic ACM precursor formulation can be used to produce substrates of various forms with porosities ranging from 55-85% and pore sizes ranging from 8-30 microns. ACM is an ideal ceramic for use in diesel engine exhaust aftertreatment applications, such as diesel particulate filters, because products based on ACM provide superior filtration efficiency, pressure drop, hysteresis, fuel economy, packaging size reduction and lower exhaust system cost. The ability to tune the material to high porosity and large pore size also enables high catalyst loading without significant impact to pressure drop. DPFs with integrated de-NOx catalytic functionality (selective catalytic reduction filters) exhibit excellent NOx reduction along with outstanding filtration efficiency, pressure drop performance.

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Old toilets await new life as Poticrete aggregate. Credit: City of Bellingham, Wash.

There seems to some new and interesting surges of interest in using recycled material in roadways, both for economic reasons and to find a second life for materials destined for the trash heap.

For example, Eileen recently wrote about new work conducted at Michigan State University showing the benefits of using ground waste glass in concrete (which, besides potentially diverting glass from landfills, also reportedly made the concrete stronger, more durable and more resistant to water). This glass-concrete mix was field tested at several sites on the MSU campus, including driveways, heated pavements, sidewalks, gutters, curbs and parking stands.

In fact, the concept of using recycled materials for roadways and the like has probably been around as long as old asphalt has been dug up and concrete has been demolished.

My (limited) memory of efforts to both innovate and standardize some of this work goes back to the mid-1970s when Delbert Day (before his Mo-Sci fame) and Robert Schaffer did their pioneer work on demonstrating how to best mix surplus waste glass with asphalt, which they named “Glassphalt”, and which eventually led to their publishing the Glassphalt Paving Handbook.

But there are apparently enough new projects of this type sprouting up (and promoters proclaiming the “green” benefits that can be accrued) that a group rooted in the University of Washington felt the need to set up a nonprofit organization to establish a rating system for transportation infrastructure projects. Named the Greenroads Foundation — this new group seems to be similar to the now-ubiquitous Leadership in Energy and Environmental Design (aka LEEDs) certification developed by the U.S. Green Building Council.

Greenroads actually was formed in 2010 by the University of Washington’s Department of Civil and Environmental Engineering and CH2M Hill an international engineering design firm. And, after one formative year under its belt, Greenroads has issued its first certification: It has awarded a “silver” certification to Bellingham, Wash., for that city’s use of what it calls “Poticrete,” i.e., concrete, in which the aggregate is made from crushed used porcelain toilet components.

A news release from the University of Washington provides some of the history behind the Poticrete project. Bellingham had plans for a multi-use recreation trail project known as the Meador Kansas Ellis Trail, the final link of the much larger Whatcom Creek recreation trail. Because the planned route for the trail passed through an urban area of the city, responsibility for constructing the various walkways, bike paths and bridges fell to the city’s Department of Public Works.

Toilets on crusher feed line. Credit: City of Bellingham, Wash.

When city project engineer Freeman Anthony heard that a local nonprofit organization was replacing old toilets for more efficient new ones and was getting ready to pitch out 400 old commodes, he had the idea that maybe they could be put to better use than being dumped in a landfill. Anthony contacted a ready-mix concrete company, Cowden Sand and Gravel, to see if they could be recycled into aggregate.

In the news release, Anthony recalls his conversation with the managers at Cowden. “They said: ‘Yeah, I think we can do something with that,’ We’ll throw it through the crusher and see what we come up with’, ” says Anthony. In the end, the crusher rendered about five tons of toilets into aggregate that was used to make the Poticrete. The porcelain chunks amounted to about one-fifth of the volume of the concrete in the 250-square-yard section in which it was used.

There wasn’t enough Poticrete to complete the entire project, so Anthony used another 80 tons of recycled concrete in the remainder of the trail’s sidewalks, curbs and gutters. In part of the roadway that required asphalt, 30 percent of it was made up of recycled content.

The Poticrete project isn’t the first “green feather” in the Whatcom Trail’s hat. It has already been recognized for using low-energy LED streetlights and employing porous concrete to manage storm water.

The Poticrete effort wasn’t a recycling-for-the-sake of recycling projects, though. Public Works officials say that the cost of crushing the toilets costs “was about the same as using virgin aggregate from regional gravel pits.”

According to the Greenroad’s website the Bellingham certification represents the first fruit of many years of behind-the-scenes work. “Sustainable roadways are not just a dream. This certification means that Greenroads’ five years of research and development has finally become a reality,” says Jeralee Anderson, executive director of Greenroads Foundation. “The Meador Kansas Ellis Trail project is a great example of the mission of the organization and further defines the practical steps that can be taken to green our roads — both nationally and internationally.”

Greenroads says its rating system parallels international standards and covers the best practices of sustainable roadway design and construction in the areas of water, environment, access, community impact, construction practices and materials. Projects nominated for certification must prove they deserve points for having achieved 11 minimum “Project Requirements.” In addition, a project can earn up to 37 extra “Voluntary Credits.” Greenroads, then, according to the website “assigns a project score based on the number of points earned by meeting the requirements and achieving credits. This score translates to one of four certification levels: Certified, Silver, Gold and Evergreen.”

Marker honoring the Poticrete installation. Credit: City of Bellingham, Wash.

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A Pakastani mother gives her child clean water in Charsarda District, an area severely affected by monsoon floods. The UN World Water Assessment Programme released its triennial report on global water issues. Credit: UNICEF/ZAK; UN.

The theme of this year’s United Nations World Water Day (March 22) is “Water and Food Security.” Every three years the UN World Water Assessment Program releases a report that provides an “authoritative picture of the state, use and management of the world’s freshwater resources.” The 4th edition of the United Nations World Water Development Report was released yesterday in conjunction with the first day of the 6th World Water Forum being held this week in Marseille, France.

The report is big — three volumes totaling over 2,000 pages: Vol. 1, Managing Water under Uncertainty and Risk; Vol. 2, Knowledge Base and Vol. 3, Facing the Challenges. The press release accompanying the report begins, “Surface and groundwater resources in Europe and North America often contain a mix of pollutants, such as nutrients, metals, pesticides, microbes, industrial chemicals and pharmaceutical products, all of which have adverse effects on freshwater ecosystems and human health, warns the United Nations.”

A powerful new tool could soon be added to the water purification arsenal. A professor at Wright State University, Sharmila Mukhopadhyay, is making coated carbon nanotube devices, and they appear to be able to meet the challenge to remove a variety of pollutants from freshwater.

Electron microscope image of nanocatalyst particles on carbon nanotubes. Credit: Mukhopadhyay; Wright State University

The device is comprised of CNTs grown on porous substrates and coated with active nanoparticles. It is like a fuzzy nanobrush with extremely high surface area and can be customized to the clean-up job. She says in an email, “Nanocatalysts can be attached to these surfaces for breaking up pollutants or facilitating other reactions.” For example, silver is an anti-bacterial agent, palladium catalyzes the decomposition of carbon-tetrachloride and titania is a sun-activated photocatalyst.

In regard to the material’s multifunctionality, Mukhopadhyay says in a university press release, “simultaneously you can combine multiple environmental cleanup applications into one single component. In an Innovation News Daily story online, she said, “These are very, very small samples able to clean quite a bit of water.” In her lab, researchers have made CNT purifiers 2 millimeters by 4 millimeters that can purify a few gallons at a time.

The “nanobrush” purifiers build on earlier work published in 2009, where her team demonstrated the ability to grow CNTs on porous substrates, mimicking the “hierarchical branching” common in biological systems with internal and external functional surfaces thanks to “coatings” of capillaries, hairs, alveoli, etc., Up to then, most CNTs were grown on flat, nonporous surfaces.

Growing the CNTs on porous platforms imparts benefit, too. Mukhopadhyay explained, “They provide the advantages of nano-structures without the environmental concerns, since the nanomaterials are strongly attached to larger robust substrates and do not escape into the environment.”

Mukhopadhyay and several industrial partners, including MetaMateria Technologies of Columbus, Ohio, recently won Ohio Third Frontier funding of just under $1 million for a project to commercialize the technology. The successful proposal was titled, “Water Purification using Nano-Enabled Solutions.”

Mukhopadhyay, a past president of ACerS’ Electronics Division, is director of Wright State’s Center for Nano-Scale Multifunctional Materials and professor of mechanical and materials engineering.

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Is there a recommended daily allowance for nanoparticles? If so, powdered donuts are a reliable source. Credit: kilrothi; Wikipedia; Creative Commons license.

How do you like your nanopowders? I like mine on a leisurely Sunday morning, with a cup of coffee and the Sunday paper. That’s because some of the delicious whiteness of a powdered donut is actually nanosize titania. (If only the “substrates” had a less macroscopic affect on body mass index!)

I did not know about the nano-titania and donut connection until I talked to a favorite college student, who told me about a chemistry lab that involved “extracting” the nanopowdered TiO₂ from donuts and getting anthrocyanin from blueberries to make a rudimentary solar cell. (I was surprised to find out that I’m late to this knowledge. Wired magazine has a how-to video and a physics professor in South Carolina is all over it like white-on-donuts. It is proof, too, that one can learn a lot by talking to one’s children.)

Applications for these puny particles with their unique properties seem to be without limit. But there are also concerns about safety regarding processing, handling and use. And rightly so — nobody wants another “asbestos” or “thalidomide” — but as a report issued late last year says, “The size label ‘nano‘ does not also immediately mean ‘toxic,’ so it does not represent an intrinsic hazard characteristic“ (authors’ emphasis).

The report (pdf) out of Germany, “10 Years of Research: Risk Assessment, Human and Environmental Toxicology of Nanomaterials,” is a status paper published by the DECHMA/VCI working group, “Responsible Production and Use of Nanomaterials.” The working group is comprised of mostly German and Swiss chemists, so the emphasis is on German risk assessment projects, but encompasses some European research projects, too.

Also, in January we told you about a report by the National Academies calling for a cohesive plan for research safety issues regarding nanotechnology and also a Danish database concept for cataloging and evaluating risks. Readers may recall our earlier story about the safety of sunscreens with nanosize ZnO particles, too.

One of the theme areas of the Fourth International Congress on Ceramics (July 15-19, Chicago, Ill.) is Nanostructured Ceramics. At present, six invited talks are scheduled—including the conference’s keynote speech by Maxine Savitz, “Materials: An Enabler”—and over two dozen poster sessions.

The talks and posters address processing, properties and applications of nanoceramics, and many will touch on health and safety issues, either directly or indirectly.

Debra Kaiser of NIST, for example, is giving an invited talk, “Environmental, Health and Safety Assessment of Engineered Nanomaterials.” The abstract explains:

The promise of nanotechnologies and the ensuring economic and societal benefits may never be fully realized due to unknown risks of engineered nanomaterials (ENMs)-materials with at least one dimension in the 1 to 100 nm range that are purposefully produced-and ENM-enabled products throughout all stages of their life cycles. ENMs pose risks to the environment (E) and the health (H) and safety (S) of workers, consumers, and the public. The National Nanotechnology Initiative recently released a document entitled 2011 Environmental Health and Safety Research Strategy, which is the product of an interagency effort on research needs to enable assessment of the EHS risks of ENMs. NIST is the lead agency on the development of a Nanomaterial Measurement Infrastructure, a suite of tools that enable accurate, precise, and reproducible measurements of nanomaterial properties. The needs and status of the tools-protocols, standards (reference materials and documentary standards), instruments, models, and data-will be described, with a particular emphasis on the importance of ENM standards.

Kathleen Eggleson of the University of Notre Dame will talk about mesoporous silica nanopowders, and the balance between health-enhancement and toxicology of nanoparticles in her invited talk, “Mesoporous Silica Nanoparticles and the Quest to Deliver Biomedical Benefits.”

Mesoporous silica nanoparticles have emerged as nanobiotechnology standouts, particularly as drug delivery vehicles. MSNs are advantageous due to capacities to: transport large molecular payloads within their pores, enhance solubility of hydrophobic pharmaceuticals, target drug release, and control release kinetics through multiple mechanisms. MSNs have demonstrated potential as doxorubicin vehicles toward overcoming multiple drug resistance of tumors. Recent studies have pointed to MSN pore structure as critical in cell-nanoparticle interactions. When MSNs were incubated with phosphate-buffered saline, loss of pore integrity was associated with increased hemolytic activity. While some have found that elicitation of pro-inflammatory and apoptotic responses are significantly reduced with MSNs compared with colloidal silica nanoparticles equivalent in shape and size, others conclude that their toxicological qualities are roughly equivalent. This talk will explore the latest research regarding MSNs with respect to biomedical outcomes.

Other talks and posters do not focus directly on EHS issues, but the more we understand about processing nanomaterials, the better we will be able handle them on a commercial-scale. Jon Binner of Loughborough University (UK) will present work in his poster, “Processing of Nanostructured Ceramics,” which is on the verge of commercialization.

Microstructures of nano and conventional, commercial yttria partially, or fully, stabilized zirconia. Credit: Binner.

The ability to produce genuinely nanostructured ceramics with mean grain sizes <100 nm has been achieved for yttria partially stabilized zirconia and is being developed for alumina, barium titanate, zirconia toughened alumina and yttrium aluminum garnet under a range of different Government and industrially-funded projects. Prototype components have already been produced and characterized for the YSZ, BT and ZTA and the work on YSZ is expected to be licensed to an industrial company before Easter 2012 for subsequent commercialization. This presentation will highlight the key steps and demonstrate the achievements. Opportunities to fund research into the processing of other nanostructured ceramics will be presented.

Jow-Lay Huang of National Cheng Kung University will also focus on processing in his invited talk, “Spark plasma sintering of β-Si3N4 nanoceramic and its indentation behavior.”

The elastoplastic deformation mechanisms are different for the two ceramics during indentation tests. Credit: Huang.

A successful fabrication of high wearing parts based on Si₃N₄ polycrystal requires an understanding of several important properties of this material, of which the mechanical deformation behavior is the most significant. Investigating the processes controlling the contact deformation and micro-fracturing behavior of Si₃N₄ based materials are thus of physical interest and technological importance, and the mechanical and tribological properties can be much improved. A commercial available nanosized β-Si₃N₄ doped with uniformly dispersed sintering additives has been used and consolidated by spark plasma sintering. The use of slow and fast heating rate yield nanosized and large, elongated β-Si₃N₄ based grains, respectively. During SPS process, temperature differences between inner and outer graphite mold and overshooting, which are related to power input and arrangement of graphite mold, are taken into consideration. The effects of microstructure on the indentation responses and micro-damaged evolution of spark-plasma-sintered β-Si₃N₄ based ceramics has been evaluated through depth-sensing-indentation tests. It was found that the nanoceramic and its coarse-grained counterpart exhibit similar elastoplastic behavior in their indentation responses. However, the increased hardness and ratio of elastic work to total work done in the nanoceramic suggest that the resistance to plastic deformation is greater than that in the coarser-grained one. The microcracking behavior within the indented materials is also evaluated and proposed in the present study.

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