Category Archives: water

Water is key component to making sub-10nm semiconducting wires

An April 6, 2015 news item on phys.org announces a new technique for making nanowires,

Water is the key component in a Rice University process to reliably create patterns of metallic and semiconducting wires less than 10 nanometers wide.

The technique by the Rice lab of chemist James Tour builds upon its discovery that the meniscus – the curvy surface of water at its edge – can be an effective mask to make nanowires.

The Rice team of Tour and graduate students Vera Abramova and Alexander Slesarev have now made nanowires between 6 and 16 nanometers wide from silicon, silicon dioxide, gold, chromium, tungsten, titanium, titanium dioxide and aluminum. They have also made crossbar structures of conducting nanowires from one or more of the materials.

An April 6, 2015 Rice University news release (also on EurekAlert), which originated the news item, explains why this could have an impact on the semiconductor industry and provides a few more details about the process,

The process is promising for the semiconductor industry as it seeks to make circuits ever smaller. State-of-the-art integrated circuit fabrication allows for signal wires that approach 10 nanometers, visible only with powerful microscopes. These are the paths that connect the billions of transistors in modern electronic devices.

“This could have huge ramifications for chip production since the wires are easily made to sub-10-nanometer sizes,” Tour said of the Rice process. “There’s no other way in the world to do this en masse on a surface.”

Current approaches to making such tiny wires take several paths. Lithography, the standard method for etching integrated circuits, is approaching the physical limits of its ability to shrink them further. Bulk synthesis of semiconducting and metallic nanowires is also possible, but the wires are difficult to position in integrated circuits.

Water’s tendency to adhere to surfaces went from an annoyance to an advantage when the Rice researchers found they could use it as a mask to make patterns. The water molecules gather wherever a raised pattern joins the target material and forms a curved meniscus created by the surface tension of water.

The meniscus-mask process involves adding and then removing materials in a sequence that ultimately leaves a meniscus covering the wire and climbing the sidewall of a sacrificial metal mask that, when etched away, leaves the nanowire standing alone.

Tour said the process should work with modern fabrication technology with no modifications to existing equipment and minimal changes in fabrication protocols. No new tools or materials are needed.

The researchers have provided an image,

These nanowires were created at Rice University through a process called meniscus-mask lithography. From left, they’re made of silicon, silicon dioxide, gold, chromium, tungsten, titanium, titanium dioxide and aluminum. The scale bar is 1 micron for all images. (Credit: Tour Group/Rice University)

These nanowires were created at Rice University through a process called meniscus-mask lithography. From left, they’re made of silicon, silicon dioxide, gold, chromium, tungsten, titanium, titanium dioxide and aluminum. The scale bar is 1 micron for all images. (Credit: Tour Group/Rice University)

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

Meniscus-Mask Lithography for Fabrication of Narrow Nanowires by Vera V. Abramova, Alexander S Slesarev, and James M. Tour. Nano Lett., Just Accepted Manuscript DOI: 10.1021/nl504716u Publication Date (Web): March 31, 2015
Copyright © 2015 American Chemical Society

The paper is freely available but you do need to register on the site for open access.

Filtration membranes with twice as much ability to remove unwanted materials from water

A March 26, 2015 news item on Nanowerk offers information about a new method for removing pollutants from water and some insight into the situation regarding bisphenol A (BPA) in Europe,

New types of membrane adsorbers remove unwanted particles from water and also, at the same time, dissolved substances such as the hormonally active bis-phenol A or toxic lead. To do this, researchers at the Fraunhofer Institute for Interfacial Engineering and Biotechnology IGB imbed selective adsorber particles in filtration membranes.

It was not until January 2015 that the European Food Safety Authority (EFSA) lowered the threshold value for bisphenol A in packaging. The hormonally active bulk chemical is among other things a basic material for polycarbonate from which, for example, CDs, plastic tableware or spectacles glasses are manufactured. Due to its chemical structure, bisphenol A is not completely degraded in the biological stages of treatment plants and is discharged into rivers and lakes by the purification facility.

Activated carbon or adsorber materials are already used to remove chemicals, anti-biotics [sic] or heavy metals from waste or process water. However, a disadvantage of these highly porous materials is the long contact time that the pollutants require to diffuse into the pores. So that as many of the harmful substances as possible are captured even in a shorter time, the treatment plants use larger quantities of adsorbers in correspondingly large treatment basins. However, activated carbon can only be regenerated with a high energy input, resulting for the most part in the need to dispose of large quantities of material contaminated with pollutants.

Also, membrane filtration with nanofiltration or reverse osmosis membranes, which can remove the contaminating substances, is not yet cost-effective for the removal of dissolved molecules from high-volume flows such as process or wastewater. Membranes filter the water through their pores when a pressure is built up on one side of the membrane, thus holding back larger molecules and solid particles. But the smaller the membrane pores are, the higher the pressure – and therefore the more energy – that is required to separate the substances from water.

A March 24, 2015 Fraunhofer Institute for Interfacial Engineering and Biotechnology (IGB) press release, which originated the news item, goes on to describe their team’s new approach,

Researchers at the Fraunhofer Institute for Interfacial Engineering and Biotechnology IGB in Stuttgart have opted for a new approach that combines the advantages of both methods. When manufacturing the membranes they add small, polymeric adsorber particles. The resulting membrane adsorbers can – in addition to their filtration function – adsorptively bind substances dissolved in water. “We make use of the porous structure of the membrane located underneath the separation layer. The pores have a highly specific surface so that as many particles as possible can be imbedded, and they also provide optimum accessibility,” says Dr. Thomas Schiestel, Head of the “Inorganic Interfaces and Membranes” working group at the Fraunhofer IGB.

“Unlike conventional adsorbers, our membrane adsorbers transport the pollutants convectively. This means that, with the water flowing rapidly through the membrane pores, a contact time lasting only a few seconds is sufficient to adsorb pollutants on the particle surface,” says the scientist. Up to 40 percent of the weight of the membrane adsorbers is accounted for by the particles, so their binding capacity is correspondingly high. At the same time the membrane adsorbers can be operated at low pressures. As the membranes can be packed very tightly, very large volumes of water can be treated even with small devices.

Functional adsorber particles

The researchers manufacture the adsorber particles in a one-step, cost-efficient process. In this patented process monomeric components are polymerized with the help of a crosslinking agent to generate 50 to 500 nanometer polymer globules. “Depending on which substances are to be removed from the water, we select the most suitable one from a variety of monomers with differing functional groups,” Schiestel explains. The spectrum here ranges from pyridine, which tends to be hydrophobic, by way of cationic ammonium compounds and includes anionic phosphonates.

Selective removal of pollutants and metals

The researchers were able to show in various tests that the membrane adsorbers remove pollutants very selectively by means of the particles, which are customized for the particular contaminant in question. For example, membrane adsorbers with pyridine groups bind the hydrophobic bisphenol A especially well, whereas those with amino groups adsorb the negatively charged salt of the antibiotic penicillin G.

“The various adsorber particles can even be combined in one membrane. In this way we can remove several micropollutants simultaneously with just one membrane adsorber,” says Schiestel, pointing out a further advantage. Equipped with different functional groups, the membrane adsorbers can also remove toxic heavy metals such as lead or arsenic from the water. Phosphonate membrane adsorbers, for example, adsorb more than 5 grams of lead per square meter of membrane surface area – 40 percent more than a commercially available membrane adsorber.

Cost-effective and regenerable

So that the membrane adsorbers can be used several times, the adsorbed pollutants have to be detached once again from the particles in the membrane. “Membrane adsorbers for bisphenol A can be fully regenerated by a shift of the pH value,” Schiestel explains. The concentrated pollutants can then be disposed off cost-effectively or broken down using suitable oxidative processes.

The regenerability of the membrane adsorbers also makes possible a further application: reutilization of the separated molecules. This additionally makes the technology attractive for recovering valuable precious metals or rare earth metals.

The Fraunhofer IGB is presenting the membrane adsorbers and other innovative technologies for water purification at the “Wasser Berlin International” Trade Fair and Congress from 24th to 27th March 2015 in Berlin. The IGB is in Hall 2.2, Stand 422.

While it’s too late to attend the presentation, here are two links and citations to papers concerning the work,

Removal of micropollutants from water by nanocomposite membrane adsorbers by Klaus Niedergall, Monika Bach, Thomas Hirth, Günter E.M. Tovar, and Thomas Schiestel. Separation and Purification Technology, Volume 131, 27 June 2014 DOI: 10.1016/j.seppur.2014.04.032

Nanostructured Composite Adsorber Membranes for the Reduction of Trace Substances in Water: The Example of Bisphenol A by Klaus Niedergall, Monika Bach, Thomas Schiestel, and Günter E.M. Tovar. Ind. Eng. Chem. Res., 2013, 52 (39), pp 14011–14018 DOI: 10.1021/ie303264r Publication Date (Web): May 16, 2013

Copyright © 2013 American Chemical Society

Both articles are behind a paywall.

Frogs: monitoring them, finding new species, and research about the golden ones in Panama

I have three frog-oriented items and while they’re not strictly speaking in my usual range of topics, given this blog’s name and the fact I haven’t posted a frog piece in quite a while, it seems this is a good moment to address that lack.

Monitoring frogs and amphibians at Trent University (Ontario, Canada)

From a March 23, 2015 Trent University news release,

With the decline of amphibian populations around the world, a team of researchers led by Trent University’s Dr. Dennis Murray will seek to establish environmental DNA (eDNA) monitoring of amphibian occupancy and aquatic ecosystem risk assessment with the help of a significant grant of over $596,000 from the Natural Sciences and Engineering Research Council of Canada (NSERC).

Awarded to Professor Murray, a Canada research chair in integrative wildlife conservation, bioinformatics, and ecological modelling and professor at Trent University along with colleagues Dr. Craig Brunetti of the Biology department, and Dr. Chris Kyle of the Forensic Science program, and partners at Laurentian University, University of Toronto, McGill University, Ontario Ministry of Natural Resources and Forestry and Environment Canada, the grant will support the development of tools that will promote a cleaner aquatic environment.

The project will use amphibian DNA found in natural breeding habitats to determine the presence and abundance of amphibians as well as their pathogens. This new technology capitalizes on Trent University’s expertise and infrastructure in the areas of wildlife DNA and water quality.

“We’re honoured to have received the grant to help us drive the project forward,” said Prof. Murray. “Our plan is to place Canada, and Trent, in a leadership position with respect to aquatic wildlife monitoring and amphibian conservation.”

Amphibian populations are declining worldwide, yet in Canada, amphibian numbers are not monitored closely, meaning changes in their distribution or abundance may be unnoticeable. Amphibian monitoring in Canada is conducted by citizen scientists who record frog breeding calls when visiting bodies of water during the spring. However, the lack of formalized amphibian surveys leaves Canada in a vulnerable position regarding the status of its diverse amphibian community.

Prof. Murray believes that the protocols developed from this project could revolutionize how amphibian populations are monitored in Canada and in turn lead to new insights regarding the population trends for several amphibian species across the country.

Here’s more about NSERC and Trent University from the news release,

About NSERC

NSERC is a federal agency that helps make Canada a country of discoverers and innovators. The agency supports almost 30,000 post-secondary students and postdoctoral fellows in their advanced studies. NSERC promotes discovery by funding approximately 12,000 professors every year and fosters innovation by encouraging over 2,400 Canadian companies to participate and invest in post-secondary research projects.

The NSERC Strategic Project Grants aim to increase research and training in areas that could strongly influence Canada’s economy, society or environment in the next 10 years in four target areas: environmental science and technologies; information and communications technologies; manufacturing; and natural resources and energy.

About Trent University

One of Canada’s top universities, Trent University was founded on the ideal of interactive learning that’s personal, purposeful and transformative. Consistently recognized nationally for leadership in teaching, research and student satisfaction, Trent attracts excellent students from across the country and around the world. Here, undergraduate and graduate students connect and collaborate with faculty, staff and their peers through diverse communities that span residential colleges, classrooms, disciplines, hands-on research, co-curricular and community-based activities. Across all disciplines, Trent brings critical, integrative thinking to life every day. As the University celebrates its 50th anniversary in 2014/15, Trent’s unique approach to personal development through supportive, collaborative community engagement is in more demand than ever. Students lead the way by co-creating experiences rooted in dialogue, diverse perspectives and collaboration. In a learning environment that builds life-long passion for inclusion, leadership and social change, Trent’s students, alumni, faculty and staff are engaged global citizens who are catalysts in developing sustainable solutions to complex issues. Trent’s Peterborough campus boasts award-winning architecture in a breathtaking natural setting on the banks of the Otonabee River, just 90 minutes from downtown Toronto, while Trent University Durham delivers a distinct mix of programming in the GTA.

Trent University’s expertise in water quality could be traced to its proximity to Canada’s Experimental Lakes Area (ELA), a much beleaguered research environment due to federal political imperatives. You can read more about the area and the politics in this Wikipedia entry. BTW, I am delighted to learn that it still exists under the auspices of the International Institute for Sustainable Development (IISD),

Taking this post into nanotechnology territory while mentioning the ELA, Trent University published a Dec. 8, 2014 news release about research into silver nanoparticles,

For several years, Trent University’s Dr. Chris Metcalfe and Dr. Maggie Xenopoulos have dedicated countless hours to the study of aquatic contaminants and the threat they pose to our environment.

Now, through the efforts of the International Institute for Sustainable Development (IISD), their research is reaching a wider audience thanks to a new video (Note: A link has been removed).

The video is one of a five-part series being released by the IISD that looks into environmental issues in Canada. The video entitled “Distilling Science at the Experimental Lakes Area: Nanosilver” and featuring Professors Metcalfe and Xenopoulos profiles their research around nanomaterials at the Experimental Lakes Area.

Prof. Xenopolous’ involvement in the project falls in line with other environmental issues she has tackled. In the past, her research has examined how human activities – including climate change, eutrophication and land use – affect ecosystem structure and function in lakes and rivers. She has also taken an interest in how land use affects the material exported and processed in aquatic ecosystems.

Prof. Metcalfe’s ongoing research on the fate and distribution of pharmaceutical and personal care products in the environment has generated considerable attention both nationally and internationally.

Together, their research into nanomaterials is getting some attention. Nanomaterials are submicroscopic particles whose physical and chemical properties make them useful for a variety of everyday applications. They can be found in certain pieces of clothing, home appliances, paint, and kitchenware. Initial laboratory research conducted at Trent University showed that nanosilver could strongly affect aquatic organisms at the bottom of the food chain, such as bacteria, algae and zooplankton.

To further examine these effects in a real ecosystem, a team of researchers from Trent University, Fisheries and Oceans Canada and Environment Canada has been conducting studies at undisclosed lakes in northwestern Ontario. The Lake Ecosystem Nanosilver (LENS) project has been monitoring changes in the lakes’ ecosystem that occur after the addition of nanosilver.

“In our particular case, we will be able to study and understand the effects of only nanosilver because that is the only variable that is going to change,” says Prof. Xenopoulos. “It’s really the only place in the world where we can do that.”

The knowledge gained from the study will help policy-makers make decisions about whether nanomaterials can be a threat to aquatic ecosystems and whether regulatory action is required to control their release into the environment.

You can find the 13 mins. video here: https://www.youtube.com/watch?v=_nJai_B4YH0#action=share

Shapeshifting frogs, a new species in Ecuador

Caption: This image shows skin texture variation in one individual frog (Pristimantis mutabilis) from Reserva Las Gralarias. Note how skin texture shifts from highly tubercular to almost smooth; also note the relative size of the tubercles on the eyelid, lower lip, dorsum and limbs. Credit: Zoological Journal of the Linnean Society

Caption: This image shows skin texture variation in one individual frog (Pristimantis mutabilis) from Reserva Las Gralarias. Note how skin texture shifts from highly tubercular to almost smooth; also note the relative size of the tubercles on the eyelid, lower lip, dorsum and limbs.
Credit: Zoological Journal of the Linnean Society

Here’s more about the shapeshifting and how the scientists figured out what the frogs were doing (from a March 23, 2015 Case Western Research University news release on EurekAlert; Note: A link has been removed),

A frog in Ecuador’s western Andean cloud forest changes skin texture in minutes, appearing to mimic the texture it sits on.

Originally discovered by a Case Western Reserve University PhD student and her husband, a projects manager at Cleveland Metroparks’ Natural Resources Division, the amphibian is believed to be the first known to have this shape-shifting capability.

But the new species, called Pristimantis mutabilis, or mutable rainfrog, has company. Colleagues working with the couple recently found that a known relative of the frog shares the same texture-changing quality–but it was never reported before.

The frogs are found at Reserva Las Gralarias, a nature reserve originally created to protect endangered birds in the Parish of Mindo, in north-central Ecuador.

The researchers, Katherine and Tim Krynak, and colleagues from Universidad Indoamérica and Tropical Herping (Ecuador) co-authored a manuscript describing the new animal and skin texture plasticity in the Zoological Journal of the Linnean Society this week. They believe their findings have broad implications for how species are and have been identified. The process may now require photographs and longer observations in the field to ensure the one species is not mistakenly perceived as two because at least two species of rain frogs can change their appearance.

Katherine Krynak believes the ability to change skin texture to reflect its surroundings may enable P. mutabilis to help camouflage itself from birds and other predators.

The Krynaks originally spotted the small, spiny frog, nearly the width of a marble, sitting on a moss-covered leaf about a yard off the ground on a misty July night in 2009. The Krynaks had never seen this animal before, though Tim had surveyed animals on annual trips to Las Gralarias since 2001, and Katherine since 2005.

They captured the little frog and tucked it into a cup with a lid before resuming their nightly search for wildlife. They nicknamed it “punk rocker” because of the thorn-like spines covering its body.

The next day, Katherine Krynak pulled the frog from the cup and set it on a smooth white sheet of plastic for Tim to photograph. It wasn’t “punk “–it was smooth-skinned. They assumed that, much to her dismay, she must have picked up the wrong frog.

“I then put the frog back in the cup and added some moss,” she said. “The spines came back… we simply couldn’t believe our eyes, our frog changed skin texture!

“I put the frog back on the smooth white background. Its skin became smooth.”

“The spines and coloration help them blend into mossy habitats, making it hard for us to see them,” she said. “But whether the texture really helps them elude predators still needs to be tested.”

During the next three years, a team of fellow biologists studied the frogs. They found the animals shift skin texture in a little more than three minutes.

Juan M. Guayasamin, from Universidad Tecnológica Indoamérica, Ecuador, the manuscript’s first author, performed morphological and genetic analyses showing that P. mutabilis was a unique and undescribed species. Carl R. Hutter, from the University of Kansas, studied the frog’s calls, finding three songs the species uses, which differentiate them from relatives. The fifth author of the paper, Jamie Culebras, assisted with fieldwork and was able to locate a second population of the species. Culebras is a member of Tropical Herping, an organization committed to discovering, and studying reptiles and amphibians.

Guayasamin and Hutter discovered that Prismantis sobetes, a relative with similar markings but about twice the size of P. mutabilis, has the same trait when they placed a spiny specimen on a sheet and watched its skin turn smooth. P. sobetes is the only relative that has been tested so far.

Because the appearance of animals has long been one of the keys to identifying them as a certain species, the researchers believe their find challenges the system, particularly for species identified by one or just a few preserved specimens. With those, there was and is no way to know if the appearance is changeable.

The Krynaks, who helped form Las Gralarias Foundation to support the conservation efforts of the reserve, plan to return to continue surveying for mutable rain frogs and to work with fellow researchers to further document their behaviors, lifecycle and texture shifting, and estimate their population, all in effort to improve our knowledge and subsequent ability to conserve this paradigm shifting species.

Further, they hope to discern whether more relatives have the ability to shift skin texture and if that trait comes from a common ancestor. If P. mutabilis and P. sobetes are the only species within this branch of Pristimantis frogs to have this capability, they hope to learn whether they retained it from an ancestor while relatives did not, or whether the trait evolved independently in each species.

Golden frog of Panama and its skin microbiome

Caption: Researchers studied microbial communities on the skin of Panamanian golden frogs to learn more about amphibian disease resistance. Panamanian golden frogs live only in captivity. Continued studies may help restore them back to the wild. Credit: B. Gratwicke/Smithsonian Conservation Biology Institute

Caption: Researchers studied microbial communities on the skin of Panamanian golden frogs to learn more about amphibian disease resistance. Panamanian golden frogs live only in captivity. Continued studies may help restore them back to the wild.
Credit: B. Gratwicke/Smithsonian Conservation Biology Institute

Among many of the pressures on frog populations, there’s a lethal fungus which has affected some 200 species of frogs. A March 23, 2015 news item on ScienceDaily describes some recent research into the bacterial communities present on frog skin,

A team of scientists including Virginia Tech researchers is one step closer to understanding how bacteria on a frog’s skin affects its likelihood of contracting disease.

A frog-killing fungus known as Batrachochytrium dendrobatidis, or Bd, has already led to the decline of more than 200 amphibian species including the now extinct-in-the-wild Panamanian golden frog.

In a recent study, the research team attempted to apply beneficial bacteria found on the skin of various Bd-resistant wild Panamanian frog species to Panamanian golden frogs in captivity, to see if this would stimulate a defense against the disease.

A March 23, 2015 Virginia Tech University news release on EurekAlert, which originated the news item, provides a twist and a turn in the story (Note: Links have been removed),

They found that while the treatment with beneficial bacteria was not successful due to its inability to stick to the skin, there were some frogs that survived exposure to the fungus.

These survivors actually had unique bacterial communities on their skin before the experiments started.

The next step is to explore these new bacterial communities.

“We were disappointed that the treatment didn’t work, but glad to have discovered new information about the relationship between these symbiotic microbial communities and amphibian disease resistance,” said Lisa Belden, an associate professor of biological sciences in the College of Science, a Fralin Life Science Institute affiliate, and a faculty member with the new Global Change Center at Virginia Tech. “Every bit of information gets us closer to getting these frogs back into nature.”

Studying the microbial communities of Panamanian golden frogs was the dissertation focus of Belden’s former graduate student Matthew Becker, who graduated with a Ph.D. in biological sciences from Virginia Tech in 2014 and is now a fellow at the Smithsonian Conservation Biology Institute.

“Anything that can help us predict resistance to this disease is very useful because the ultimate goal of this research is to establish healthy populations of golden frogs in their native habitat,” Becker told Smithsonian Science News. “I think identifying alternative probiotic treatment methods that optimize dosages and exposure times will be key for moving forward with the use of probiotics to mitigate chytridiomycosis.”

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

Composition of symbiotic bacteria predicts survival in Panamanian golden frogs infected with a lethal fungus by Matthew H. Becker , Jenifer B. Walke , Shawna Cikanek , Anna E. Savage , Nichole Mattheus , Celina N. Santiago , Kevin P. C. Minbiole , Reid N. Harris , Lisa K. Belden , Brian Gratwicke. April 2015 Volume: 282 Issue: 1805 DOI: 10.1098/rspb.2014.2881 Published 18 March 2015

This is an open access paper.

For anyone curious about the article in the Smithsonian mentioned in the news release, you can find it here.

 

Disinfectants without chemicals for the food industry

Michael Berger in his March 16, 2015 Nanowerk Spotlight article profiles some very interesting research into replacing chemicals with water nanostructures,

The burden of foodborne diseases worldwide is huge, with serious economic and public health consequences. The CDC [US Centers for Disease Control] estimates that each year in the USA approximately 48 million people get sick, 128,000 get hospitalized and 3,000 die from the consumption of food contaminated with pathogenic microorganisms. The food industry is in search of effective intervention methods that can be applied from ‘farm to fork’ to ensure the safety of the food chain and be consumer and environment friendly at the same time.

In the food industry, chemicals are routinely used to clean and disinfect product contact surfaces as well as the outer surface of the food itself. These chemicals provide a necessary and required step to ensure that the foods produced and consumed are as free as possible from microorganisms that can cause foodborne illness.

Food activists are concerned that some of the chemicals used by the food industry for disinfection can cause health issues for consumers. A prime example is the current discussion in Europe about ‘American chlorine chicken’. …

Berger goes on to highlight the research being conducted at the Harvard T. Chan School of Public Health (Harvard University). The team announced a new technique called Engineered Water Nanostructures (EWNS), which is generated by electrospraying water. The team published this paper in 2014,

A chemical free, nanotechnology-based method for airborne bacterial inactivation using engineered water nanostructures by Georgios Pyrgiotakis, James McDevitt, Andre Bordini, Edgar Diaz, Ramon Molina, Christa Watson, Glen Deloid, Steve Lenard, Natalie Fix, Yosuke Mizuyama, Toshiyuki Yamauchi, Joseph Brain and Philip Demokritou. Environ. Sci.: Nano, 2014,1, 15-26 DOI: 10.1039/C3EN00007A

First published online 28 Nov 2013

This paper is open access.

More recently, the team has proved the efficacy of this technique on stainless steel surfaces and tomatoes. A Feb. 25, 2015 Harvard T. Chan School of Public Health news release provides information about the costs of foodborne diseases and goes on to describe the technique and the latest experiments,

The burden of foodborne diseases worldwide is huge, with serious economic and public health consequences. The U.S. Department of Agriculture’s (USDA’s) Economic Research Service reported in 2014 that foodborne illnesses are costing the economy more than $15.6 billion and about 53,245 Americans visit the hospital annually due to foodborne illnesses. The food industry is in search of effective intervention methods that can be applied form “farm to fork” to ensure the safety of the food chain and be consumer and environment friendly at the same time.

Researchers at the Center for Nanotechnology and Nanotoxicology of the Harvard T. Chan School of Public Health are currently exploring the effectiveness of a nanotechnology based, chemical free, intervention method for the inactivation of foodborne and spoilage microorganisms on fresh produce and on food production surfaces. This method utilizes Engineered Water Nanostructures (EWNS) generated by electrospraying of water. EWNS possess unique properties; they are 25 nm in diameter, remain airborne in indoor conditions for hours, contain Reactive Oxygen Species (ROS), have very strong surface charge (on average 10e/structure) and have the ability to interact and inactivate pathogens by destroying their membrane.

In a study funded by the USDA and just published this week in the premier Environmental Science and Technology journal, the efficacy of these tiny water nanodroplets, in inactivating representative foodborne pathogens such as Escherichia coli, Salmonella enterica and Listeria innocua, on stainless steel surfaces and on tomatoes, was assessed showing significant log reductions in inactivation of select food pathogens. These promising results could open up the gateway for further exploration into the dynamics of this method in the battle against foodborne disease. More importantly this novel, chemical-free, cost effective and environmentally friendly intervention method holds great potential for development and application in the food industry, as a ‘green’ alternative to existing inactivation methods.

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

Inactivation of Foodborne Microorganisms Using Engineered Water Nanostructures (EWNS) by Georgios Pyrgiotakis, Archana Vasanthakumar, Ya Gao, Mary Eleftheriadou, Eduardo Toledo, Alice DeAraujo, James McDevitt, Taewon Han, Gediminas Mainelis, Ralph Mitchell, and Philip Demokritou. Environ. Sci. Technol., Article ASAP DOI: 10.1021/es505868a Publication Date (Web): February 19, 2015

Copyright © 2015 American Chemical Society

This paper is behind a paywall. The researchers have made this image illustrating a ‘water shell’s’ effect on a bacterium located on a tomato,

Courtesy: Researchers and the American Chemical Society

Courtesy: Researchers and the American Chemical Society

I’m not sure how chemical companies are going to feel but this is very exciting news. Still, one has to wonder just how much water this technique would require for full scale adoption and would it be reusable?

Removing titanium dioxide nanoparticles from water may not be that easy

A March 10, 2015 news item on Nanowerk highlights some research into the removal of nanoscale titanium dioxide particles from water supplies (Note: A link has been removed),

The increased use of engineered nanoparticles (ENMs) in commercial and industrial applications is raising concern over the environmental and health effects of nanoparticles released into the water supply. A timely study that analyzes the ability of typical water pretreatment methods to remove titanium dioxide, the most commonly used ENM, is published in Environmental Engineering Science (“Titanium Dioxide Nanoparticle Removal in Primary Prefiltration Stages of Water Treatment: Role of Coating, Natural Organic Matter, Source Water, and Solution Chemistry”). The article is available free on the Environmental Engineering Science website until April 10, 2015.

A March 10, 2015 Mary Ann Liebert, Inc., publishers news release (also on EurekAlert), which originated the news item, provides more details about the work (Note: A link has been removed),

Nichola Kinsinger, Ryan Honda, Valerie Keene, and Sharon Walker, University of California, Riverside, suggest that current methods of water prefiltration treatment cannot adequately remove titanium dioxide ENMs. They describe the results of scaled-down tests to evaluate the effectiveness of three traditional methods—coagulation, flocculation, and sedimentation—in the article “Titanium Dioxide Nanoparticle Removal in Primary Prefiltration Stages of Water Treatment: Role of Coating, Natural Organic Matter, Source Water, and Solution Chemistry.”

“As nanoscience and engineering allow us to develop new exciting products, we must be ever mindful of associated consequences of these advances,” says Domenico Grasso, PhD, PE, DEE, Editor-in-Chief of Environmental Engineering Science and Provost, University of Delaware. “Professor Walker and her team have presented an excellent report raising concerns that some engineered nanomaterials may find their ways into our water supplies.”

“While further optimization of such treatment processes may allow for improved removal efficiencies, this study illustrates the challenges that we must be prepared to face with the emergence of new engineered nanomaterials,” says Sharon Walker, PhD, Professor of Chemical and Environmental Engineering, University of California, Riverside.

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

Titanium Dioxide Nanoparticle Removal in Primary Prefiltration Stages of Water Treatment: Role of Coating, Natural Organic Matter, Source Water, and Solution Chemistry by Nichola Kinsinger, Ryan Honda, Valerie Keene, and Sharon L. Walker. Environmental Engineering Science. doi:10.1089/ees.2014.0288.

This paper is freely available until April 10, 2015.

Interestingly Sharon Walker and Nichola Kinsinger recently co-authored a paper (mentioned in my March 9, 2015 post) about copper nanoparticles and water treatment which concluded this about copper nanoparticles in water supplies,

The researchers found that the copper nanoparticles, when studied outside the septic tank, impacted zebrafish embryo hatching rates at concentrations as low as 0.5 parts per million. However, when the copper nanoparticles were released into the replica septic tank, which included liquids that simulated human digested food and household wastewater, they were not bioavailable and didn’t impact hatching rates.

Taking these these two paper into account (and the many others I’ve read), there is no simple or universal answer to the question of whether or not ENPs or ENMs are going to pose environmental problems.

Copper nanoparticles, toxicity research, colons, zebrafish, and septic tanks

Alicia Taylor, a graduate student at UC Riverside, surrounded by buckets of effluent from the septic tank system she used for her research. Courtesy: University of California at Riverside

Alicia Taylor, a graduate student at UC Riverside, surrounded by buckets of effluent from the septic tank system she used for her research. Courtesy: University of California at Riverside

Those buckets of efflluent are strangely compelling. I think it’s the abundance of orange. More seriously, a March 2, 2015 news item on Nanowerk poses a question about copper nanoparticles,

What do a human colon, septic tank, copper nanoparticles and zebrafish have in common?

They were the key components used by researchers at the University of California, Riverside and UCLA [University of California at Los Angeles] to study the impact copper nanoparticles, which are found in everything from paint to cosmetics, have on organisms inadvertently exposed to them.

The researchers found that the copper nanoparticles, when studied outside the septic tank, impacted zebrafish embryo hatching rates at concentrations as low as 0.5 parts per million. However, when the copper nanoparticles were released into the replica septic tank, which included liquids that simulated human digested food and household wastewater, they were not bioavailable and didn’t impact hatching rates.

A March 2, 2015 University of California at Riverside (UCR) news release (also on EurekAlert), which originated the news item, provides more detail about the research,

“The results are encouraging because they show with a properly functioning septic tank we can eliminate the toxicity of these nanoparticles,” said Alicia Taylor, a graduate student working in the lab of Sharon Walker, a professor of chemical and environmental engineering at the University of California, Riverside’s Bourns College of Engineering.

The research comes at a time when products with nanoparticles are increasingly entering the marketplace. While the safety of workers and consumers exposed to nanoparticles has been studied, much less is known about the environmental implications of nanoparticles. The Environmental Protection Agency is currently accessing the possible effects of nanomaterials, including those made of copper, have on human health and ecosystem health.

The UC Riverside and UCLA [University of California at Los Angeles] researchers dosed the septic tank with micro copper and nano copper, which are elemental forms of copper but encompass different sizes and uses in products, and CuPRO, a nano copper-based material used as an antifungal agent to spray agricultural crops and lawns.

While these copper-based materials have beneficial purposes, inadvertent exposure to organisms such as fish or fish embryos has not received sufficient attention because it is difficult to model complicated exposure environments.

The UC Riverside researchers solved that problem by creating a unique experimental system that consists of the replica human colon and a replica two-compartment septic tank, which was originally an acyclic septic tank. The model colon is made of a custom-built 20-inch-long glass tube with a 2-inch diameter with a rubber stopper at both ends and a tube-shaped membrane typically used for dialysis treatments within the glass tube.

To simulate human feeding, 100 milliliters of a 20-ingredient mixture that replicated digested food was pumped into the dialysis tube at 9 a.m., 3 p.m. and 9 p.m. for five-day-long experiments over nine months.

The septic tank was filled with waste from the colon along with synthetic greywater, which is meant to simulate wastewater from sources such as sinks and bathtubs, and the copper nanoparticles. The researchers built a septic tank because 20 to 30 percent of American households rely on them for sewage treatment. Moreover, research has shown up to 40 percent of septic tanks don’t function properly. This is a concern if the copper materials are disrupting the function of the septic system, which would lead to untreated waste entering the soil and groundwater.

Once the primary chamber of the septic system was full, liquid began to enter the second chamber. Once a week, the effluent was drained from the secondary chamber and it was placed into sealed five-gallon containers. The effluent was then used in combination with zebrafish embryos in a high content screening process using multiwall plates to access hatching rates.

The remaining effluent has been saved and sits in 30 five-gallon buckets in a closet at UC Riverside because some collaborators have requested samples of the liquid for their experiments.

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

Understanding the Transformation, Speciation, and Hazard Potential of Copper Particles in a Model Septic Tank System Using Zebrafish to Monitor the Effluent* by Sijie Lin, Alicia A. Taylor, Zhaoxia Ji, Chong Hyun Chang, Nichola M. Kinsinger, William Ueng, Sharon L. Walker, and André E. Nel. ACS Nano, 2015, 9 (2), pp 2038–2048 DOI: 10.1021/nn507216f
Publication Date (Web): January 27, 2015

Copyright © 2015 American Chemical Society

This paper is behind a paywall.

* Link added March 10, 2015.

Water report from the UN (United Nations)

This is outside my usual range of topics but given water’s importance in our survival I am inclined to feature this new UN (United Nations) report on water. From a Feb. 22, 2015 UN University (UNU) Institute for Water, Environment and Health (INWEH) news release on EurekAlert,

A new UN report warns that without large new water-related investments many societies worldwide will soon confront rising desperation and conflicts over life’s most essential resource.

The news release describes the situation,

Continued stalling, coupled with population growth, economic instability, disrupted climate patterns and other variables, could reverse hard-earned development gains and preclude meaningful levels of development that can be sustained into the future.

Says lead author Bob Sandford, EPCOR Chair, Canadian Partnership Initiative in support of the UN Water for Life Decade: “The consequence of unmet water goals will be widespread insecurity creating more international tension and conflict. The positive message is that if we can keep moving now on water-related Sustainable Development Goals we can still have the future we want.”

Published in the run-up to the adoption this September of universal post-2015 Sustainable Development Goals (SDGs), the report provides an in-depth analysis of 10 countries to show how achieving water and sanitation-related SDGs offers a rapid, cost effective way to achieve sustainable development.

The 10 countries given the analysis are not the ‘usual suspects’ (from the news release),

The countries included in the study cover the full range of economic and development spectrum: Bangladesh, Bolivia, Canada, Indonesia, Republic of Korea, Pakistan, Singapore, Uganda, Vietnam, and Zambia.

Based on the national case studies, the report prescribes country level steps for achieving the global water targets.

No US. No China. No Middle Eastern countries. No Australia. No India. No Japan. No European countries. There is one North American country, two African countries and one South American country in addition to the Asian countries. To my knowledge none of the included countries is strongly associated with desert regions.

It’s an interesting set of choices and the report offers no explanation as to why these 10 countries rather than 10 others. You can check if for yourself on p. 29 (the introductory first page of Part Three: Learning from National Priorities and Strategies) of the 2015 Water in the World We Want report.

Water scarcity hurts everybody

Moving on to the report’s recommendations as noted in the news release,

Among top recommendations: Hold the agriculture sector (which guzzles roughly 70% of world water supplies), and the energy sector (15%), accountable for making efficiencies while transitioning to clean energy including hydropower.

Prepared in association with the Global Water Partnership and Canada’s McMaster University, the report says the success of global efforts on the scale required rests in large part on a crackdown on widespread corruption in the water sector, particularly in developing countries.

“In many places … corruption is resulting in the hemorrhaging of precious financial resources,” siphoning an estimated 30% of funds earmarked for water and sanitation-related improvements.

The report underscores the need for clearly defined anti-corruption protocols enforced with harsh penalties.

Given accelerating Earth system changes and the growing threat of hydro-climatic disruption, corruption undermining water-related improvements threatens the stability and very existence of some nation states, which in turn affects all other countries, the report says.

“Corruption at any level is not just a criminal act in its own right. In the context of sustainable development it could be viewed as a crime against all of humanity.”

The report notes that the world’s water and wastewater infrastructure maintenance and replacement deficit is building at a rate of $200 million per year, with $1 trillion now required in the USA alone.

To finance its recommendations, the report says that, in addition to plugging the leakage of funds to corruption, $1.9 trillion in subsidies to petroleum, coal and gas industries should be redirected by degrees.

The estimated global cost to achieve post-2015 sustainable development goals in water and sanitation development, maintenance and replacement is US $1.25 trillion to $2.25 trillion per year for 20 years, a doubling or tripling of current spending translating into 1.8 to 2.5 percent of global GDP.

The resulting benefits would be commensurately large, however – a minimum of $3.11 trillion per year, not counting health care savings and valuable ecosystem service enhancements.

Changes in fundamental hydrology “likely to cause new kinds of conflict”

Sandford and co-lead author Corinne J. Schuster-Wallace of UNU-INWEH underline that all current water management challenges will be compounded one way or another by climate change, and by increasingly unpredictable weather.

“Historical predictability, known as relative hydrological stationarity … provides the certainty needed to build houses to withstand winds of a certain speed, snow of a certain weight, and rainfalls of certain intensity and duration, when to plant crops, and to what size to build storm sewers. The consequence is that the management of water in all its forms in the future will involve a great deal more uncertainty than it has in the past.”

“In a more or less stable hydro-climatic regime you are playing poker with a deck you know and can bet on risk accordingly. The loss of stationarity is playing poker with a deck in which new cards you have never seen before keep appearing more and more often, ultimately disrupting your hand to such an extent that the game no longer has coherence or meaning.”

“People do not have the luxury of living without water and when faced with a life or death decision, people tend to do whatever they must to survive … Changes in fundamental hydrology are likely to cause new kinds of conflict, and it can be expected that both water scarcity and flooding will become major trans-boundary water issues.”

Within 10 years, researchers predict 48 countries – 25% of all nations on Earth with an expected combined population of 2.9 billion – will be classified “water-scarce” (1,000 to 1,700 cubic meters of water per capita per year) or “water-stressed” (1,000 cubic meters or less). [emphases mine]

And by 2030, expect overall global demand for freshwater to exceed supply by 40%, with the most acute problems in warmer, low-resource nations with young, fast-growing populations, according to the report. [emphasis mine]

An estimated 25% of the world’s major river basins run dry for part of each year, the report notes, and “new conflicts are likely to emerge as more of the world’s rivers become further heavily abstracted so that they no longer make it to the sea.”

Meanwhile, the magnitude of floods in Pakistan and Australia in 2010, and on the Great Plains of North America in 2011 and 2014, “suggests that the destruction of upstream flood protection and the failure to provide adequate downstream flood warning will enter into global conflict formulae in the future.”

The report cites the rising cost of world flood-related damages: US$53 billion in 2013 and more than US$312 billion since 2004.

Included in the global flood figures: roughly $1 billion in flood damage in the Canadian province of Manitoba in both 2011 and 2014. The disasters have affected the province’s economic and political stability, contributing to a budget deficit, an unpopular increase in the provincial sales tax and to the consequent resignation of political leaders. [emphases mine]

UNU-INWEH Director Zafar Adeel and Jong Soo Yoon, Head of the UN Office for Sustainable Development, state: “Through a series of country case studies, expert opinion, and evidence synthesis, the report explores the critical role that water plays (including sanitation and wastewater management) in sustainable development; current disconnects between some national development plans and the proposed SDGs; opportunities for achieving sustainable development through careful water management; and implementation opportunities.”

The report, they add, “fills a critical gap in understanding the complexities associated with water resources and their management, and also provides substantive options that enable us to move forward within the global dialogue.”

Juxtaposing the situation in Manitoba with the situation in warmer, low-resource nations emphasizes the universality of the problem. Canadians can be complacent about water scarcity, especially where I live in the Pacific Northwest, but it affects us all.

Corruption bites everywhere

As for the corruption mentioned in the news release and report, while there is no news of ‘water’ corruption here, the country does have its own track record with regard to financial boondoggles. For example, the Auditor-General reported in 2013 that $3.1B spent on measures to combat terrorism was unaccounted for (from an April 30, 2013 Globe & Mail article by Gloria Galloway and Daniel Leblanc),

The federal government cannot account for billions of dollars that were devoted to combatting terrorism after the Sept. 11 [2001] attacks, Canada’s Auditor-General says in a new report.

Between 2001 and 2009, Ottawa awarded $12.9-billion to 35 departments and agencies charged with ensuring the safety of Canadians to use for public security and fighting terrorism. The money allocated through the Public Security and Anti-Terrorism Initiative was intended to pay for measures designed to keep terrorists out of Canada, to prosecute those found in the country, to support international initiatives, and to protect infrastructure.

But Auditor-General Michael Ferguson said only $9.8-billion of that money was identified in reports to the Treasury Board as having been spent specifically on anti-terrorism measures by the departments and agencies. The rest was not recorded as being used for that purpose. Some was moved to other priorities, and some lapsed without being spent, but the government has no full breakdown for the $3.1-billion.

The time period 2001 – 2009 implicates both Liberal and Conservative governments, the Conservatives having come to power in 2006.

About Bob Sandford and EPCOR

One final note, the report’s co-lead author, Bob Sandford, is described as the chair for EPCOR Canadian Partnership Initiative in support of the UN Water for Life Decade, It’s a rather interesting title in that Sandford is not on the EPCOR board. Here’s how EPCOR describes Sandford on the company’s webpage dedicated to him and dated March 13, 2013,

Robert Sandford is the EPCOR Chair in support of the United Nations “Water for Life” Decade of Action initiative in Canada. We support his efforts as he speaks in plain language to policy makers, explaining how his work links research and analysis to public policy ideas that help protect water supplies and reduce water consumption.

We’re proud to sponsor his leadership efforts to educate Canadians and help local and international governments become better stewards of a most precious resource. Supporting Robert is just one of the ways EPCOR works to protect water in our communities.

The company which is owned solely by the city of Edmonton (Alberta) was originally named Edmonton Electric Lighting and Power Company in 1891. As they say on the company’s About page, “We provide electricity and water services to customers in Canada and the US.” They also develop some nice public relations strategies. I’m referring, of course, to the Sandford sponsorship which can be better appreciated by going to Sandford’s, from the homepage,

Bob Sandford is the EPCOR Chair of the Canadian Partnership Initiative in support of United Nations “Water for Life” Decade. This national partnership initiative aims to inform the public on water issues and translate scientific research outcomes into language decision-makers can use to craft timely and meaningful public policy.

Bob is also the Director of the Western Watersheds Research Collaborative and an associate of the Centre for Hydrology which is part of the Global Water Institute at the University of Saskatchewan. Bob is also a Fellow of the Biogeoscience Institute at the University of Calgary. He sits on the Advisory Board of Living Lakes Canada, the Canadian Chapter of Living Lakes International and is also a member of the Forum for Leadership on Water (FLOW), a national water policy research group centred in Toronto. Bob also serves as Water Governance Adviser and Senior Policy Author for Simon Fraser University’s Adaptation to Climate Change Team. In 2011, Bob was invited to be an advisor on water issues by the Interaction Council, a global public policy forum composed of more than thirty former Heads of State including Canadian Prime Minister Jean Chretien, U.S. President Bill Clinton, and the former Prime Minister of Norway, Gro Brundtland. In this capacity Bob works to bring broad international example to bear on Canadian water issues. In 2013, Alberta Ventures magazine recognized Bob as one of the year’s 50 most influential Albertans.

I guess Mr. Sandford knows his water.

Poopy gold, silver, platinum, and more

In the future, gold rushes could occur in sewage plants. Precious metals have been found in large quantity by researchers investigating waste and the passage of nanoparticles (gold, silver, platinum, etc.) into our water. From a Jan. 29, 2015 news article by Adele Peters for Fast Company (Note: Links have been removed),

One unlikely potential source of gold, silver, platinum, and other metals: Sewage sludge. A new study estimates that in a city of a million people, $13 million of metals could be collecting in sewage every year, or $280 per ton of sludge. There’s gold (and silver, copper, and platinum) in them thar poop.

Funded in part by a grant for “nano-prospecting,” the researchers looked at a huge sample of sewage from cities across the U.S., and then studied several specific waste treatment plants. “Initially we thought gold was at just one or two hotspots, but we find it even in smaller wastewater treatment plants,” says Paul Westerhoff, an engineering professor at Arizona State University, who led the new study.

Some of the metals likely come from a variety of sources—we may ingest tiny particles of silver, for example, when we eat with silverware or when we drink water from pipes that have silver alloys. Medical diagnostic tools often use gold or silver. …

The metallic particles Peters is describing are nanoparticles some of which are naturally occurring  as she notes but, increasingly, we are dealing with engineered nanoparticles making their way into the environment.

Engineered or naturally occurring, a shocking quantity of these metallic nanoparticles can be found in our sewage. For example, a waste treatment centre in Japan recorded 1,890 grammes of gold per tonne of ash from incinerated sludge as compared to the 20 – 40 grammes of gold per tonne of ore recovered from one of the world’s top producing gold mines (Miho Yoshikawa’s Jan. 30, 2009 article for Reuters).

While finding it is one thing, extracting it is going to be something else as Paul Westerhoff notes in Peters’ article. For the curious, here’s a link to and a citation for the research paper,

Characterization, Recovery Opportunities, and Valuation of Metals in Municipal Sludges from U.S. Wastewater Treatment Plants Nationwide by Paul Westerhoff, Sungyun Lee, Yu Yang, Gwyneth W. Gordon, Kiril Hristovski, Rolf U. Halden, and Pierre Herckes. Environ. Sci. Technol., Article ASAP DOI: 10.1021/es505329q Publication Date (Web): January 12, 2015

Copyright © 2015 American Chemical Society

This paper is behind a paywall.

On a completely other topic, this is the first time I’ve noticed this type of note prepended to an abstract,

 Note

This article published January 26, 2015 with errors throughout the text. The corrected version published January 27, 2015.

Getting back to the topic at hand, I checked into nano-prospecting and found this Sept. 19, 2013 Arizona State University news release describing the project launch,

Growing use of nanomaterials in manufactured products is heightening concerns about their potential environmental impact – particularly in water resources.

Tiny amounts of materials such as silver, titanium, silica and platinum are being used in fabrics, clothing, shampoos, toothpastes, tennis racquets and even food products to provide antibacterial protection, self-cleaning capability, food texture and other benefits.

Nanomaterials are also put into industrial polishing agents and catalysts, and are released into the environment when used.

As more of these products are used and disposed of, increasing amounts of the nanomaterials are accumulating in soils, waterways and water-systems facilities. That’s prompting efforts to devise more effective ways of monitoring the movement of the materials and assessing their potential threat to environmental safety and human health.

Three Arizona State University faculty members will lead a research project to help improve methods of gathering accurate information about the fate of the materials and predicting when, where and how they may pose a hazard.

Their “nanoprospecting” endeavor is supported by a recently awarded $300,000 grant from the National Science Foundation.

You can find out more about Paul Westerhoff and his work here.

Cleaning water with palladium nanoparticle catalysts

A Jan. 16, 2015 news item on Nanowerk describes research into using palladium as a catalyst for water remediation efforts,

One way of removing harmful nitrate from drinking water is to catalyse its conversion to nitrogen. This process suffers from the drawback that it often produces ammonia. By using palladium nanoparticles as a catalyst, and by carefully controlling their size, this drawback can be partially eliminated. It was research conducted by Yingnan Zhao of the University of Twente’s MESA+ Institute for Nanotechnology that led to this discovery.

A Jan. 14, 2015 University of Twente press release, which originated the news item, describes the problem and suggested solution; this was research for a PhD thesis,

Due to the excessive use of fertilizers, our groundwater is contaminated with nitrates, which pose a problem if they enter the mains water supply. Levels have fallen significantly in recent years, as a result of various European directives. In addition, the Integrated Approach to Nitrogen programme was launched in various Dutch nature reserves at the start of January. Tackling the problem at source is one thing, but it will still be necessary to treat the mains water supply. While this can be achieved through biological conversion – bacteria convert the nitrate to nitrogen gas-, this is a slow process. Using palladium to catalyse the conversion of nitrate to nitrogen speeds up the process enormously. However, this reaction suffers from the drawback that it produces a harmful by-product – ammonia.

Exposed surface

The amount of ammonia produced appears to depend on the method used to prepare the palladium and on the catalyst’s physical structure. Yingnan Zhao decided to use nanometre-sized colloidal palladium particles, as their dimensions can be easily controlled. These particles are fixed to a surface, so they do not end up in the mains water supply. However, it is important to stop them clumping together, so stabilizers such as polyvinyl alcohol are added. Unfortunately, these stabilizers tend to shield the surface of the palladium particles, which reduces their effectiveness as a catalyst. By introducing additional treatments, Yingnan Zhao has managed to fully expose the catalytic surface once again or to manipulate it in a controlled manner. This has resulted in palladium nanoparticles that can catalyse the conversion to nitrogen, while producing very little ammonia. This has brought the further development of catalytic water treatment (in compact devices for home use, for example) one step closer.

Yingnan Zhao, who is from Heze, Shandong, China, conducted his research in Prof. Leon Lefferts’ Catalytic Processes and Materials group. He defended his thesis, which is entitled “Colloidal Nanoparticles as Catalysts and Catalyst Precursors for Nitrite Hydrogenation” on Thursday 15 January [2015].

I trust Zhao successfully defended this thesis and perhaps more importantly helped to develop a new and better method for water remediation made necessary by the effects of fertilizers.

Egypt steps it up nanowise with a Center for Nanotechnology

Dec. 16, 2014 Egypt’s Prime Minister Ibrahim Mahlab along with other ministers and Dr. Ahmed Zewail, Chairman of the board of Zewail City of Science and Technology (this seems to be a campus with a university and a number of research institutes), announced Egypt’s Center for Nanotechnology (from a Zewail City of Science and Technology Dec. 16, 2014 press release),

The Center, funded by the National Bank of Egypt, cost over $ 100 Million and is, till this moment, the biggest research Center Egypt has seen. This center is hailed as a turning point in the development of scientific research in Egypt as it will allow researchers to develop nanoparticles and nanostructured applications that will improve, even revolutionize, many technology and industry sectors including: information technology, energy, environmental science, medicine, and food safety among many others.

During the visit, Dr. Zewail gave Mahlab and the Cabinet members a brief introduction about the City’s constituents, achievements, and how it is going to improve Egypt’s economic development.

Impressed by the magnitude of Zewail City, Mahalab expressed his excitement about the effect this project is going to have on the future of scientific research in Egypt.

Following the opening ceremony, they all moved to the construction site of the soon-to-be Zewail City new premises, in Hadayk October, to evaluate the progress of the construction process. This construction work is the result of the presidential decree issued on April 9, 2014 to allocate 200 acres for Zewail City in 6th of October City. The construction work is expected to be done by the end of 2015, and will approximately cost $ 1.5 billion.

The end of 2015 is a very ambitious goal for completion of this center but these projects can sometimes inspire people to extraordinary efforts and there seems to be quite a bit of excitement about this one if the video is any indication. From a Dec. 22, 2014 posting by Makula Dunbar, which features a CCTV Africa clip, on AFKInsider,

I was interested to learn from the clip that Egypt’s new constitution mandates at least 1% of the GDP (gross domestic product) must be earmarked for scientific research.

As for Ahmed Zewail, in addition to being Chairman of the board of Zewail City of Science and Technology, he is also a professor at the California Institute of Technology (CalTech). From his CalTech biography page (Note: A link has been removed),

Ahmed Zewail is the Linus Pauling Chair professor of chemistry and professor of physics at the California Institute of Technology (Caltech). For ten years, he served as the Director of the National Science Foundation’s Laboratory for Molecular Sciences (LMS), and is currently the Director of the Moore Foundation’s Center for Physical Biology at Caltech.

On April 27, 2009, President Barack Obama appointed him to the President’s Council of Advisors on Science and Technology, and in November of the same year, he was named the First United States Science Envoy to the Middle East.

The CalTech bio page is a bit modest, Zewail’s Wikipedia entry gives a better sense of this researcher’s eminence (Note: Links have been removed),

Ahmed Hassan Zewail (Arabic: أحمد حسن زويل‎, IPA: [ˈæħmæd ˈħæsæn zeˈweːl]; born February 26, 1946) is an Egyptian- American scientist, known as the “father of femtochemistry”, he won the 1999 Nobel Prize in Chemistry for his work on femtochemistry and became the first Egyptian scientist to win a Nobel Prize in a scientific field. …

If you watched the video, you may have heard a reference to ‘other universities’. The comment comes into better focus after reading about the dispute between Nile University and Zewail City (from the Wikipedia entry),

Nile University has been fighting with Zewail City of Science and Technology, established by Nobel laureate Ahmed Zewail, for more than two years over a piece of land that both universities claim to be their own.

A March 22, 2014 ruling turned down challenges to a verdict issued in April 2013 submitted by Zewail City. The court also ruled in favour of the return of Nile University students to the contested buildings.

In a statement released by Nile University’s Student Union before Saturday’s decision, the students stated that the verdict would test the current government’s respect to the judiciary and its rulings.

Zewail City, meanwhile, stressed in a statement released on Saturday that the recent verdict rules on an urgent level; the substantive level of the case is yet to be ruled on. Sherif Fouad, Zewail City’s spokesman and media adviser, said the verdict “adds nothing new.” It is impossible for Zewail City to implement Saturday’s verdict and take Nile University students into the buildings currently occupied by Zewail City students, he said.

If I understand things rightly, the government has pushed forward with this Zewail City initiative (Center for Nanotechnology) while the ‘City’ is still in a dispute over students and buildings with Nile University. This should make for some interesting dynamics (tension) for students, instructors, and administrators of both the institutions and may not result in those dearly hoped for scientific advances that the government is promoting. Hopefully, the institutions will resolve their conflict in the interest of promoting good research.