Category Archives: construction

Drip dry housing

This piece on new construction materials does have a nanotechnology aspect although it’s not made clear exactly how nanotechnology plays a role.

From a Dec. 28, 2016 news item on phys.org (Note: A link has been removed),

The construction industry is preparing to use textiles from the clothing and footwear industries. Gore-Tex-like membranes, which are usually found in weather-proof jackets and trekking shoes, are now being studied to build breathable, water-resistant walls. Tyvek is one such synthetic textile being used as a “raincoat” for homes.

You can find out more about Tyvek here.on the Dupont website.

A Dec. 21, 2016 press release by Chiara Cecchi for Youris ((European Research Media Center), which originated the news item, proceeds with more about textile-type construction materials,

Camping tents, which have been used for ages to protect against wind, ultra-violet rays and rain, have also inspired the modern construction industry, or “buildtech sector”. This new field of research focuses on the different fibres (animal-based such as wool or silk, plant-based such as linen and cotton and synthetic such as polyester and rayon) in order to develop technical or high-performance materials, thus improving the quality of construction, especially for buildings, dams, bridges, tunnels and roads. This is due to the fibres’ mechanical properties, such as lightness, strength, and also resistance to many factors like creep, deterioration by chemicals and pollutants in the air or rain.

“Textiles play an important role in the modernisation of infrastructure and in sustainable buildings”, explains Andrea Bassi, professor at the Department of Civil and Environmental Engineering (DICA), Politecnico of Milan, “Nylon and fiberglass are mixed with traditional fibres to control thermal and acoustic insulation in walls, façades and roofs. Technological innovation in materials, which includes nanotechnologies [emphasis mine] combined with traditional textiles used in clothes, enables buildings and other constructions to be designed using textiles containing steel polyvinyl chloride (PVC) or ethylene tetrafluoroethylene (ETFE). This gives the materials new antibacterial, antifungal and antimycotic properties in addition to being antistatic, sound-absorbing and water-resistant”.

Rooflys is another example. In this case, coated black woven textiles are placed under the roof to protect roof insulation from mould. These building textiles have also been tested for fire resistance, nail sealability, water and vapour impermeability, wind and UV resistance.

Photo: Production line at the co-operative enterprise CAVAC Biomatériaux, France. Natural fibres processed into a continuous mat (biofib) – Martin Ansell, BRE CICM, University of Bath, UK

In Spain three researchers from the Technical University of Madrid (UPM) have developed a new panel made with textile waste. They claim that it can significantly enhance both the thermal and acoustic conditions of buildings, while reducing greenhouse gas emissions and the energy impact associated with the development of construction materials.

Besides textiles, innovative natural fibre composite materials are a parallel field of the research on insulators that can preserve indoor air quality. These bio-based materials, such as straw and hemp, can reduce the incidence of mould growth because they breathe. The breathability of materials refers to their ability to absorb and desorb moisture naturally”, says expert Finlay White from Modcell, who contributed to the construction of what they claim are the world’s first commercially available straw houses, “For example, highly insulated buildings with poor ventilation can build-up high levels of moisture in the air. If the moisture meets a cool surface it will condensate and producing mould, unless it is managed. Bio-based materials have the means to absorb moisture so that the risk of condensation is reduced, preventing the potential for mould growth”.

The Bristol-based green technology firm [Modcell] is collaborating with the European Isobio project, which is testing bio-based insulators which perform 20% better than conventional materials. “This would lead to a 5% total energy reduction over the lifecycle of a building”, explains Martin Ansell, from BRE Centre for Innovative Construction Materials (BRE CICM), University of Bath, UK, another partner of the project.

“Costs would also be reduced. We are evaluating the thermal and hygroscopic properties of a range of plant-derived by-products including hemp, jute, rape and straw fibres plus corn cob residues. Advanced sol-gel coatings are being deposited on these fibres to optimise these properties in order to produce highly insulating and breathable construction materials”, Ansell concludes.

You can find Modcell here.

Here’s another image, which I believe is a closeup of the processed fibre shown in the above,

Production line at the co-operative enterprise CAVAC Biomatériaux, France. Natural fibres processed into a continuous mat (biofib) – Martin Ansell, BRE CICM, University of Bath, UK [Note: This caption appears to be a copy of the caption for the previous image]

Luminous electronic tiles (lumentile)

A Dec. 19, 2016 news item on Nanowerk introduces a ceramic tile that can be given a different look at the touch of a fingertip,

Using pioneering photonics technology, The ‘Luminous Electronic Tile’, or LUMENTILE, project mixes the simplicity of a plain ceramic tile with the complexity of today’s sophisticated touch screen technology, creating a light source and unparalleled interaction. All it takes is one tap to change the colour, look or mood of any room in your house.

This is the first time anyone has tried to embed electronics into ceramics or glass for a large-scale application. With the ability to play videos or display images, the tiles allow the user to turn their walls into a large ‘cinema’ screen, where each unit acts as a set of pixels of the overall display.

An undated Horizon 2020 webpage describes the ‘digital wallpaper’ in more detail,

Scientists from Italy have created ‘digital wallpaper’, allowing for a constant change in design and aesthetic controlled via a smartphone, tablet or computer.

Each Luminous Electronic Tile – or Lumentile – acts as a touch screen which can change colour, pattern or light intensity, play videos or display images.

If numerous tiles are arranged together, they can create a ‘cinema’ screen with each tile acting as a set of pixels for the overall display.

The combination of ceramic, glass and electronics could allow the user to have interchangeable control of the look and design of their surroundings by tapping the tile.

Each tile can be arranged to completely or partially cover walls of a room, floor or ceiling.

However, they can also be transferred to the exterior of buildings, as either flat or curved tiles to fit around columns or uneven surfaces.

Project co-ordinator Professor Guido Giuliani, said: “It may sound like the stuff of James Bond but external tiles would create a ‘chameleonic skin’ or instant camouflage.

“Although we are a long way off this yet, this would allow a car or building to blend completely into its surroundings, and hence ‘disappear’.”

Although these tiles cannot be purchased yet, they hope to be available to users in two years, with mass production by the end of 2020.

Lumentile received a grant of more than €2.4m from the Horizon 2020 programme via the Photonics Public Private Partnership. Created in Italy by the Universita Degli Studi Di Pavia, the Lumentile project also has a number of European partners from Finland, Switzerland and Spain.

A combination of ceramic, glass and organic electronics, the luminous tile includes structural materials, solid-state light sources and electronic chips and can be controlled with a central computer, a smart phone or tablet. [downloaded from http://www.nanowerk.com/nanotechnology-news/newsid=45417.php]

You can find a bit more information on the Lumentile project website.

Are living bacteria providing camouflage for crustaceans?

When you have no place to hide, you can develop some unique methods to avoid detection according to an Oct. 27, 2016 news item on ScienceDaily,

Crustaceans that thrive in the vastness of the open ocean have no place to hide from their predators. Consequently, many creatures that live at depths where sunlight fades to darkness have developed transparent bodies to be less visible when spotted against the twilight by upward-looking predators. But they also face predators with bioluminescent searchlights that should cause the clear animals to flash brightly, just like shining a flashlight across a window pane.

Well, it turns out the midwater crustaceans have camouflage for that too.

An Oct. 27, 2016 Duke University news release on EurekAlert, which originated the news item, expands on the theme,

A new study from Duke University and the Smithsonian Institution has found that these midwater hyperiid amphipods are covered with anti-reflective coatings on their legs and bodies that can dampen the reflection of light by 250-fold in some cases and prevent it from bouncing back to a hungry lantern fish’s eye.

Weirder still, these coatings appear to be made of living bacteria.

When viewed under an electron microscope, the optical coating appears as a sheet of fairly uniform beads, smaller than the wavelength of light. “This coating of little spheres reduces reflections the same way putting a shag carpet on the walls of a recording studio would soften echoes,” said study leader Laura Bagge, a Ph.D. candidate at Duke working with biologist Sönke Johnsen.

The spheres range from 50 to 300 nanometers in diameter on different species of amphipod, but a sphere of 110 nm would be optimal, resulting in up to a 250-fold reduction in reflectance, Bagge calculated. “But every size of these bumps helps.”

Adding to the impression that the spheres might be bacteria, they are sometimes connected with a net of filaments like a biofilm. Each of the seven amphipod species Bagge looked at appears to have its own species of symbiotic optical bacteria. But that’s not a sure thing yet.

“They have all the features of bacteria, but to be 100 percent sure, we’re going to have to perform an in-depth sequencing project,” Bagge said. That project is already underway.

If the spheres are bacteria, they’re very small ones. But it’s not hard to imagine the natural selection — having your host spotted and eaten — that would drive the microbes to an optimal size, said research zoologist Karen Osborn of the Smithsonian National Museum of Natural History, who provided some of the species for this study.

If the optical coating is alive, the researchers will have to figure out how this symbiotic relationship got started in the first place.

Crustaceans molt to grow, shedding the old shell and perhaps its attendant anti-reflective bacteria. But Osborn thinks it would be pretty easy to re-seed the animal’s new shell. “In that whole process, they’re touching the old carapace.” There’s also a species of hyperiid, Phronima, that raises its young in a little floating nest hollowed out of the body of a salp. In that case, the kids could adopt mom’s anti-reflective bacteria pretty easily, Osborn said.

Another amphipod species, Cystisoma, also extrudes brush-like structures on the exoskeleton of its legs which are just the right size and shape to serve the same purpose as the antireflective spheres. At up to six inches in length, Cystisoma has a serious need for stealth.

“They’re remarkably transparent,” Osborn said. “Mostly you see them because you don’t see them. When you pull up a trawl bucket packed full of plankton, you see an empty spot – why is nothing there? You reach in and pull out a Cystisoma. It’s a firm cellophane bag, essentially.”

“We care about this for the basic biology,” Bagge said. But the discovery of living anti-reflective coatings may have technological applications as well. Reflection-reducing “nipple arrays” are being used in the design of glass windows and have also been found in the eyes of moths, apparently to help them see better at night.

Here’s a link to and a citation for the paper,

Nanostructures and Monolayers of Spheres Reduce Surface Reflections in Hyperiid Amphipods by Laura E. Bagge, Karen J. Osborn, Sönke Johnsen. Current Biology DOI: http://dx.doi.org/10.1016/j.cub.2016.09.033 Publication stage: In Press Corrected Proof

This paper is behind a paywall.

Do you have a proposal for living building materials?

DARPA (US Defense Advanced Research Projects Agency) has launched a program called Engineered Living Materials (ELM) and issued an invitation. From an Aug. 9, 2016 news item on Nanowerk,

The structural materials that are currently used to construct homes, buildings, and infrastructure are expensive to produce and transport, wear out due to age and damage, and have limited ability to respond to changes in their immediate surroundings. Living biological materials—bone, skin, bark, and coral, for example—have attributes that provide advantages over the non-living materials people build with, in that they can be grown where needed, self-repair when damaged, and respond to changes in their surroundings. The inclusion of living materials in human-built environments could offer significant benefits; however, today scientists and engineers are unable to easily control the size and shape of living materials in ways that would make them useful for construction.

DARPA is launching the Engineered Living Materials (ELM) program with a goal of creating a new class of materials that combines the structural properties of traditional building materials with attributes of living systems. Living materials represent a new opportunity to leverage engineered biology to solve existing problems associated with the construction and maintenance of built environments, and to create new capabilities to craft smart infrastructure that dynamically responds to its surroundings.

An Aug. 5, 2016 DARPA news release, which originated the news item, explains further (Note: A link has been removed),

“The vision of the ELM program is to grow materials on demand where they are needed,” said ELM program manager Justin Gallivan. “Imagine that instead of shipping finished materials, we can ship precursors and rapidly grow them on site using local resources. And, since the materials will be alive, they will be able to respond to changes in their environment and heal themselves in response to damage.”

Grown materials are not entirely new, but their current manifestations differ substantially from the materials Gallivan envisions. For instance, biologically sourced structural materials can already be grown into specified sizes and shapes from inexpensive feedstocks; packing materials derived from fungal mycelium and building blocks made from bacteria and sand are two modern examples. And, of course, wood has been used for ages. However, these products are rendered inert during the manufacturing process, so they exhibit few of their components’ original biological advantages. Scientists are making progress with three-dimensional printing of living tissues and organs, using scaffolding materials that sustain the long-term viability of the living cells. These cells are derived from existing natural tissues, however, and are not engineered to perform synthetic functions. And current cell-printing methods are too expensive to produce building materials at necessary scales.

ELM looks to merge the best features of these existing technologies and build on them to create hybrid materials composed of non-living scaffolds that give structure to and support the long-term viability of engineered living cells. DARPA intends to develop platform technologies that are scalable and generalizable to facilitate a quick transition from laboratory to commercial applications.

The long-term objective of the ELM program is to develop an ability to engineer structural properties directly into the genomes of biological systems so that neither scaffolds nor external development cues are needed for an organism to realize the desired shape and properties. Achieving this goal will require significant breakthroughs in scientists’ understanding of developmental pathways and how those pathways direct the three-dimensional development of multicellular systems.

Work on ELM will be fundamental research carried out in controlled laboratory settings. DARPA does not anticipate environmental release during the program.

For anyone who’s interested in participating in the program, there’s an announcement (download the PDF for more details) featuring a Proposers Day event on Aug. 26, 2016 being held in Arlington, Virginia,

The Proposers Day objectives are:

1) To introduce the science and technology community (industry, academia, and government) to the ELM program vision and goals;

2) To facilitate interaction between investigators that may have capabilities to develop elements of interest and relevance to ELM goals; and

3) To encourage and promote teaming arrangements among organizations that have the relevant expertise, research facilities and capabilities for executing research and development responsive to the ELM program goals.

The Proposers Day will include overview presentations and optional sidebar meetings where potential proposers can discuss ideas for proposal submissions with the Government team.

The goal of the DARPA ELM program is to explore and develop living materials that combine the structural properties of traditional building materials with attributes of living systems, including the ability to rapidly grow, to self-repair, and to adapt to the environment. Living materials represent a new opportunity to leverage engineered biology to solve existing problems associated with the construction and maintenance of our built environments, as well as to create new capabilities to craft smart infrastructure that dynamically responds to our surroundings. The specific program objectives are to develop design tools and methods that enable the engineering of structural features into cellular systems that function as living materials, thereby opening up a new design space for building technology. These new methods will be validated by the production of living materials that can reproduce, self-organize and self-heal.

You can register for the event  here. Register by 12 pm (noon) ET on Aug. 23, 2016.

Nanotechnology-enhanced roads in South Africa and in Kerala, India

It’s all about road infrastructure in these two news bits.

Road building and maintenance in sub-Saharan Africa

A July 7, 2016 news item on mybroadband.co.za describes hopes that nanotechnology-enabled products will make roads easier to build and maintain,

The solution for affordable road infrastructure development could lie in the use of nanotechnology, according to a paper presented at the 35th annual Southern African Transport Conference in Pretoria.

The cost of upgrading, maintaining and rehabilitating road infrastructure with limited funds makes it impossible for sub-Saharan Africa to become competitive in the world market, according to Professor Gerrit Jordaan of the University of Pretoria, a speaker at the conference.

The affordability of road infrastructure depends on the materials used, the environment in which the road will be built and the traffic that will be using the road, explained Professor James Maina of the department of civil engineering at the University of Pretoria.

Hauling materials to a construction site contributes hugely to costs, which planners try to minimise by getting materials closer to the site. But if there aren’t good quality materials near the site, another option is to modify poor quality materials for construction purposes. This is where nanotechnology comes in, he explained.

For example, if the material is clay soil, it has a high affinity to water so when it absorbs water it expands, and when it dries out it contracts. Nanotechnology can make the soil water repellent. “Essentially, nanotechnology changes the properties to work for the construction process,” he said.

These nanotechnology-based products have been used successfully in many parts of the world, including India, the USA and in the West African region.

There have also been concerns about road building and maintenance in Kerala, India.

Nanotechnology for city roads in Kochi

A March 23, 2015 news item in the Times of India describes an upcoming test of a nanotechnology-enabled all weather road,

Citizens can now look forward to better roads with the local self-government department planning to use nanotechnology to construct all-weather roads.

For the district trial run, the department has selected a 300-metre stretch of a panchayat road in Edakkattuvayal panchayat. The trial would experiment with nanotechnology to build moisture resistant, long-lasting and maintenance-free roads.

“Like the public, the department is also fed up with the poor condition of roads in the state. Crores of rupees are spent every year for repairing and resurfacing the roads. This is because of heavy rains in the state that weakens the soil base of roads, resulting in potholes that affect the ride-quality of the road surface,” said KT Sajan, assistant executive engineer, LSGD, who is supervising the work.

The nanotechnology has been developed by Zydex Technologies, a Gujarat-headquartered firm. The company’s technology has already been used by major private contract firms that build national highways in India and in other major projects in European and African countries.

Oddly, you can’t find out more about the Zydex products mentioned in the article on its Roads Solution webpage , where you are provided a general description of the technology,

Revolutionary nanotechnology for building moisture resistant, long lasting & maintenance free roads through innovative adaptation of Organosilane chemistry.

Zydex Nanotechnology: A Game Changer

Zydex Nanotechnology has a value propositions for all layers of the road

SOIL LAYERS
Zydex Nanotechnology makes the soil moisture resistant, reduces expansiveness and stabilizes the soil to improve its bearing strength manifold. If used with 1% cement, it can stabilize almost any type of soil, by improving the California Bearing Ratio (CBR) to even 100 or above.

Here is the real change in game, as stronger soil bases would now allow optimization of road section thicknesses, potentially saving 10-15% road construction cost.

BOND COATS
Prime & Tack coats become 100 % waterproofed, due to penetration and chemical bonding. This also ensures uniform load transfer. And all this at lower residual bitumen.

ASPHALTIC LAYERS
Chemical bonding between aggregates and asphalt eliminates moisture induced damage of asphaltic layers.

Final comment

I hadn’t meant to wait so long to publish the bit about Kerala’s road but serendipity has allowed me to link it to a piece about South Africa ‘s roads and to note a resemblance to the problems encountered in both regions.

Making better concrete by looking to nature for inspiration

Researchers from the Masssachusetts Institute of Technology (MIT) are working on a new formula for concrete based on bones, shells, and other such natural materials. From a May 25, 2016 news item on Nanowerk (Note: A link has been removed),

Researchers at MIT are seeking to redesign concrete — the most widely used human-made material in the world — by following nature’s blueprints.

In a paper published online in the journal Construction and Building Materials (“Roadmap across the mesoscale for durable and sustainable cement paste – A bioinspired approach”), the team contrasts cement paste — concrete’s binding ingredient — with the structure and properties of natural materials such as bones, shells, and deep-sea sponges. As the researchers observed, these biological materials are exceptionally strong and durable, thanks in part to their precise assembly of structures at multiple length scales, from the molecular to the macro, or visible, level.

A May 26, 2016 MIT news release (also on EurekAlert), which originated the news item, provides more detail,

From their observations, the team, led by Oral Buyukozturk, a professor in MIT’s Department of Civil and Environmental Engineering (CEE), proposed a new bioinspired, “bottom-up” approach for designing cement paste.

“These materials are assembled in a fascinating fashion, with simple constituents arranging in complex geometric configurations that are beautiful to observe,” Buyukozturk says. “We want to see what kinds of micromechanisms exist within them that provide such superior properties, and how we can adopt a similar building-block-based approach for concrete.”

Ultimately, the team hopes to identify materials in nature that may be used as sustainable and longer-lasting alternatives to Portland cement, which requires a huge amount of energy to manufacture.

“If we can replace cement, partially or totally, with some other materials that may be readily and amply available in nature, we can meet our objectives for sustainability,” Buyukozturk says.

“The merger of theory, computation, new synthesis, and characterization methods have enabled a paradigm shift that will likely change the way we produce this ubiquitous material, forever,” Buehler says. “It could lead to more durable roads, bridges, structures, reduce the carbon and energy footprint, and even enable us to sequester carbon dioxide as the material is made. Implementing nanotechnology in concrete is one powerful example [of how] to scale up the power of nanoscience to solve grand engineering challenges.”

From molecules to bridges

Today’s concrete is a random assemblage of crushed rocks and stones, bound together by a cement paste. Concrete’s strength and durability depends partly on its internal structure and configuration of pores. For example, the more porous the material, the more vulnerable it is to cracking. However, there are no techniques available to precisely control concrete’s internal structure and overall properties.

“It’s mostly guesswork,” Buyukozturk says. “We want to change the culture and start controlling the material at the mesoscale.”

As Buyukozturk describes it, the “mesoscale” represents the connection between microscale structures and macroscale properties. For instance, how does cement’s microscopic arrangement affect the overall strength and durability of a tall building or a long bridge? Understanding this connection would help engineers identify features at various length scales that would improve concrete’s overall performance.

“We’re dealing with molecules on the one hand, and building a structure that’s on the order of kilometers in length on the other,” Buyukozturk says. “How do we connect the information we develop at the very small scale, to the information at the large scale? This is the riddle.”

Building from the bottom, up

To start to understand this connection, he and his colleagues looked to biological materials such as bone, deep sea sponges, and nacre (an inner shell layer of mollusks), which have all been studied extensively for their mechanical and microscopic properties. They looked through the scientific literature for information on each biomaterial, and compared their structures and behavior, at the nano-, micro-, and macroscales, with that of cement paste.

They looked for connections between a material’s structure and its mechanical properties. For instance, the researchers found that a deep sea sponge’s onion-like structure of silica layers provides a mechanism for preventing cracks. Nacre has a “brick-and-mortar” arrangement of minerals that generates a strong bond between the mineral layers, making the material extremely tough.

“In this context, there is a wide range of multiscale characterization and computational modeling techniques that are well established for studying the complexities of biological and biomimetic materials, which can be easily translated into the cement community,” says Masic.

Applying the information they learned from investigating biological materials, as well as knowledge they gathered on existing cement paste design tools, the team developed a general, bioinspired framework, or methodology, for engineers to design cement, “from the bottom up.”

The framework is essentially a set of guidelines that engineers can follow, in order to determine how certain additives or ingredients of interest will impact cement’s overall strength and durability. For instance, in a related line of research, Buyukozturk is looking into volcanic ash [emphasis mine] as a cement additive or substitute. To see whether volcanic ash would improve cement paste’s properties, engineers, following the group’s framework, would first use existing experimental techniques, such as nuclear magnetic resonance, scanning electron microscopy, and X-ray diffraction to characterize volcanic ash’s solid and pore configurations over time.

Researchers could then plug these measurements into models that simulate concrete’s long-term evolution, to identify mesoscale relationships between, say, the properties of volcanic ash and the material’s contribution to the strength and durability of an ash-containing concrete bridge. These simulations can then be validated with conventional compression and nanoindentation experiments, to test actual samples of volcanic ash-based concrete.

Ultimately, the researchers hope the framework will help engineers identify ingredients that are structured and evolve in a way, similar to biomaterials, that may improve concrete’s performance and longevity.

“Hopefully this will lead us to some sort of recipe for more sustainable concrete,” Buyukozturk says. “Typically, buildings and bridges are given a certain design life. Can we extend that design life maybe twice or three times? That’s what we aim for. Our framework puts it all on paper, in a very concrete way, for engineers to use.”

This is not the only team looking at new methods for producing the material, my Dec. 24, 2012 posting features a number of ‘concrete’ research projects.

Also, I highlighted the reference to ‘volcanic ash’ as it reminded me of Roman concrete which has lasted for over 2000 years and includes volcanic sand and volcanic rock.  You can read more about it in a Dec. 18, 2014 article by Mark Miller for Ancient Origins where he describes the wonders of the material and what was then a recent discovery of the Romans’ recipe.

I have two links and citations, first, the MIT paper, then the paper on Roman concrete.

Roadmap across the mesoscale for durable and sustainable cement paste – A bioinspired approach by Steven D. Palkovic, Dieter B. Brommer, Kunal Kupwade-Patil, Admir Masic, Markus J. Buehler, Oral Büyüköztürk.Construction and Building Materials Volume 115, 15 July 2016, Pages 13–31.  doi:10.1016/j.conbuildmat.2016.04.020

Mechanical resilience and cementitious processes in Imperial Roman architectural mortar by Marie D. Jackson, Eric N. Landis, Philip F. Brune, Massimo Vitti, Heng Chen, Qinfei Li, Martin Kunz, Hans-Rudolf Wenk, Paulo J. M. Monteiro, and Anthony R. Ingraffea. Proceedings of the National Academy of Sciences  vol. 111 no. 52 18484–18489, doi: 10.1073/pnas.1417456111

The first paper is behind a paywall but the second one appears to be open access.

Winner of Tel Aviv University (Israel) nanoscience and nanotech centre competition

[downloaded from http://www.e-architect.co.uk/israel/tel-aviv-university-center-for-nanoscience-and-nanotechnology-competition]

[downloaded from http://www.e-architect.co.uk/israel/tel-aviv-university-center-for-nanoscience-and-nanotechnology-competition]

The image above from e-architect shows part of the reason why l’Atelier d’Architecture Michel Rémon was announced as the winner of the international architectural competition for Tel Aviv University’s Nanoscience and Nanotechnology Center. A May 4, 2016 news item on Dexigner provides some explanation,

“The final choice of the Nano building reflects the synergy between the technical needs defined by the research teams and our desire to provide an open and welcoming research environment,” commented Joseph Klafter, President of Tel Aviv University. “I have no doubt that the new building will help inspire outstanding research and global collaborations.”

The project for Tel Aviv University presents a matrix of vertical lines creating a “skin” covering the three-storey building. The structure will enable natural light control and balance out the interior-exterior ratio. Visually, the building will not feature windows or doors. [emphasis mine] Among the energy efficiency solutions suggested by the company is special glass to optimize sun energy, natural ventilation, solar panels to cool the building and a rainwater collection system. …

In place of a main door or entry, it seems, according to the image, this building will have an opening. I wonder what they mean ‘special glass’. Are the walls underneath those white strips supposed to be glass? That would explain the lack of obvious windows but how do you cool a ‘transparent’ building and deal with the glare during summer and deal with heat loss in the winter? Presumably the ‘special’ glass will address those issues.

Unfortunately, there isn’t much information available. L’Atelier d’Architecture Michel Rémon doesn’t have an announcement about this latest success on the company website. As for Tel Aviv University’s Center for Nanoscience and Nanotechnology, their website also doesn’t have an announcement.

In any event, it’s a pretty nifty design.

Transparent wood instead of glass for window panes?

The transparent wood is made by removing the lignin in the wood veneer. (Photo: Peter Larsson

The transparent wood is made by removing the lignin in the wood veneer. (Photo: Peter Larsson

Not quite ready as a replacement for some types of glass window panes, nonetheless, transparent (more like translucent) wood is an impressive achievement. According to a March 30, 2016 news item on ScienceDaily size is what makes this piece of transparent wood newsworthy,

Windows and solar panels in the future could be made from one of the best — and cheapest — construction materials known: wood. Researchers at Stockholm’s KTH Royal Institute of Technology [Sweden] have developed a new transparent wood material that’s suitable for mass production.

Lars Berglund, a professor at Wallenberg Wood Science Center at KTH, says that while optically transparent wood has been developed for microscopic samples in the study of wood anatomy, the KTH project introduces a way to use the material on a large scale. …

A March 31 (?), 2016 KTH Institute of Technology press release, which originated the news item, provides more detail,

“Transparent wood is a good material for solar cells, since it’s a low-cost, readily available and renewable resource,” Berglund says. “This becomes particularly important in covering large surfaces with solar cells.”

Berglund says transparent wood panels can also be used for windows, and semitransparent facades, when the idea is to let light in but maintain privacy.

The optically transparent wood is a type of wood veneer in which the lignin, a component of the cell walls, is removed chemically.

“When the lignin is removed, the wood becomes beautifully white. But because wood isn’t not naturally transparent, we achieve that effect with some nanoscale tailoring,” he says.

The white porous veneer substrate is impregnated with a transparent polymer and the optical properties of the two are then matched, he says.

“No one has previously considered the possibility of creating larger transparent structures for use as solar cells and in buildings,” he says

Among the work to be done next is enhancing the transparency of the material and scaling up the manufacturing process, Berglund says.

“We also intend to work further with different types of wood,” he adds.

“Wood is by far the most used bio-based material in buildings. It’s attractive that the material comes from renewable sources. It also offers excellent mechanical properties, including strength, toughness, low density and low thermal conductivity.”

The American Chemical Society has a March 30, 2016 news release about the KTH achievement on EurekAlert  highlighting another potential use for transparent wood,

When it comes to indoor lighting, nothing beats the sun’s rays streaming in through windows. Soon, that natural light could be shining through walls, too. Scientists have developed transparent wood that could be used in building materials and could help home and building owners save money on their artificial lighting costs. …

Homeowners often search for ways to brighten up their living space. They opt for light-colored paints, mirrors and lots of lamps and ceiling lights. But if the walls themselves were transparent, this would reduce the need for artificial lighting — and the associated energy costs. Recent work on making transparent paper from wood has led to the potential for making similar but stronger materials. Lars Berglund and colleagues wanted to pursue this possibility.

Here’s a link to and a citation for the paper,

Optically Transparent Wood from a Nanoporous Cellulosic Template: Combining Functional and Structural Performance by Yuanyuan Li, Qiliang Fu, Shun Yu, Min Yan, and Lars Berglund. Biomacromolecules, Article ASAP DOI: 10.1021/acs.biomac.6b00145 Publication Date (Web): March 4, 2016

Copyright © 2016 American Chemical Society

This paper appears to be open access.

Construction and nanotechnology research in Scandinavia

I keep hearing about the possibilities for better (less polluting, more energy efficient, etc.) building construction materials but there never seems to be much progress.  A June 15, 2015 news item on Nanowerk, which suggests some serious efforts are being made in Scandinavia, may help to explain the delay,

It isn’t cars and vehicle traffic that produce the greatest volumes of climate gas emissions – it’s our own homes. But new research will soon be putting an end to all that!

The building sector is currently responsible for 40% of global energy use and climate gas emissions. This is an under-communicated fact in a world where vehicle traffic and exhaust emissions get far more attention.

In the future, however, we will start to see construction materials and high-tech systems integrated into building shells that are specifically designed to remedy this situation. Such systems will be intelligent and multifunctional. They will consume less energy and generate lower levels of harmful climate gas emissions.

With this objective in mind, researchers at SINTEF are currently testing microscopic nanoparticles as insulation materials, applying voltages to window glass and facades as a means of saving energy, and developing solar cells that prevent the accumulation of snow and ice.

Research Director Susie Jahren and Research Manager Petra Rüther are heading SINTEF’s strategic efforts in the field of future construction materials. They say that although there are major commercial opportunities available in the development of green and low carbon building technologies, the construction industry is somewhat bound by tradition and unable to pay for research into future technology development. [emphasis mine]

A June 15, 2015 SINTEF (Scandinavia’s largest independent research organisation) news release on the Alpha Galileo website, which originated the news item, provides an overview of the research being conducted into nanotechnology-enabled construction materials (Note: I have added some heads and ruthlessly trimmed from the text),

[Insulation]

SINTEF researcher Bente Gilbu Tilset is sitting in her office in Forskningsveien 1 in Oslo [Norway]. She and her colleagues are looking into the manufacture of super-insulation materials made up of microscopic nanospheres.

“Our aim is to create a low thermal conductivity construction material “, says Tilset. “When gas molecules collide, energy is transferred between them. If the pores in a given material are small enough, for example less than 100 nanometres in diameter, a molecule will collide more often with the pore walls than with other gas molecules. This will effectively reduce the thermal conductivity of the gas. So, the smaller the pores, the lower the conductivity of the gas”, she says.

[Solar cells]

As part of the project “Bygningsintegrerte solceller for Norge” (Building Integrated Photovoltaics, BIPV Norway), researchers from SINTEF, NTNU, the IFE [IFE Group, privately owned company, located in Sweden] and Teknova [company created by the Nordic Institute for Studies in Innovation {NIFU}, located in Norway], are planning to look into how we can utilise solar cells as integral housing construction components, and how they can be adapted to Norwegian daylight and climatic conditions.

One of the challenges is to develop a solar cell which prevents the accumulation of snow and ice. The cells must be robust enough to withstand harsh wind and weather conditions and have lifetimes that enable them to function as electricity generators.

[Energy]

Today, we spend 90 per cent of our time indoors. This is as much as three times more than in the 1950s. We are also letting less daylight into our buildings as a result of energy considerations and construction engineering requirements. Research shows that daylight is very important to our health, well-being and biological rhythms. It also promotes productivity and learning. So the question is – is it possible to save energy and get the benefits of greater exposure to daylight?

Technologies involving thermochromic, photochromic and electrochromic pigments can help us to control how sunlight enters our buildings, all according to our requirements for daylight and warmth from the sun.

Self-healing concrete

Every year, between 40 and 120 million Euros are spent in Europe on the maintenance of bridges, tunnels and construction walls. These time-consuming and costly activities have to be reduced, and the project CAPDESIGN is aiming to make a contribution in this field.

The objective of the project is to produce concrete that can be ‘restored’ after being exposed to loads and stresses by means of self-healing agents that prevent the formation of cracks. The method involves mixing small capsules into the wet concrete before it hardens. These remain in the matrix until loads or other factors threaten to crack it. The capsules then burst and the self-healing agents are released to repair the structure.

At SINTEF, researchers are working with the material that makes up the capsule shells. The shell has to be able to protect the self-healing agent in the capsules for an extended period and then, under the right conditions, break down and release the agents in response to the formation of cracks caused by temperature, pH, or a load or stress resulting from an impact or shaking. At the same time, the capsules must not impair the ductility or the mechanical properties of the newly-mixed concrete.

You’ll notice most of the research seems to be taking place in Norway. I suspect that is due to the story having come from a joint Norwegian Norwegian University of Science and Technology (NTNU)/SINTEF, website, Gemini.no/en. Anyone wishing to test their Norwegian readings skills need only omit ‘/en’ from the URL.