Tag Archives: Romania

Thanks for the memory: the US National Institute of Standards and Technology (NIST) and memristors

In January 2018 it seemed like I was tripping across a lot of memristor stories . This came from a January 19, 2018 news item on Nanowerk,

In the race to build a computer that mimics the massive computational power of the human brain, researchers are increasingly turning to memristors, which can vary their electrical resistance based on the memory of past activity. Scientists at the National Institute of Standards and Technology (NIST) have now unveiled the long-mysterious inner workings of these semiconductor elements, which can act like the short-term memory of nerve cells.

A January 18, 2018 NIST news release (also on EurekAlert), which originated the news item, fills in the details,

Just as the ability of one nerve cell to signal another depends on how often the cells have communicated in the recent past, the resistance of a memristor depends on the amount of current that recently flowed through it. Moreover, a memristor retains that memory even when electrical power is switched off.

But despite the keen interest in memristors, scientists have lacked a detailed understanding of how these devices work and have yet to develop a standard toolset to study them.

Now, NIST scientists have identified such a toolset and used it to more deeply probe how memristors operate. Their findings could lead to more efficient operation of the devices and suggest ways to minimize the leakage of current.

Brian Hoskins of NIST and the University of California, Santa Barbara, along with NIST scientists Nikolai Zhitenev, Andrei Kolmakov, Jabez McClelland and their colleagues from the University of Maryland’s NanoCenter (link is external) in College Park and the Institute for Research and Development in Microtechnologies in Bucharest, reported the findings (link is external) in a recent Nature Communications.

To explore the electrical function of memristors, the team aimed a tightly focused beam of electrons at different locations on a titanium dioxide memristor. The beam knocked free some of the device’s electrons, which formed ultrasharp images of those locations. The beam also induced four distinct currents to flow within the device. The team determined that the currents are associated with the multiple interfaces between materials in the memristor, which consists of two metal (conducting) layers separated by an insulator.

“We know exactly where each of the currents are coming from because we are controlling the location of the beam that is inducing those currents,” said Hoskins.

In imaging the device, the team found several dark spots—regions of enhanced conductivity—which indicated places where current might leak out of the memristor during its normal operation. These leakage pathways resided outside the memristor’s core—where it switches between the low and high resistance levels that are useful in an electronic device. The finding suggests that reducing the size of a memristor could minimize or even eliminate some of the unwanted current pathways. Although researchers had suspected that might be the case, they had lacked experimental guidance about just how much to reduce the size of the device.

Because the leakage pathways are tiny, involving distances of only 100 to 300 nanometers, “you’re probably not going to start seeing some really big improvements until you reduce dimensions of the memristor on that scale,” Hoskins said.

To their surprise, the team also found that the current that correlated with the memristor’s switch in resistance didn’t come from the active switching material at all, but the metal layer above it. The most important lesson of the memristor study, Hoskins noted, “is that you can’t just worry about the resistive switch, the switching spot itself, you have to worry about everything around it.” The team’s study, he added, “is a way of generating much stronger intuition about what might be a good way to engineer memristors.”

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

Stateful characterization of resistive switching TiO2 with electron beam induced currents by Brian D. Hoskins, Gina C. Adam, Evgheni Strelcov, Nikolai Zhitenev, Andrei Kolmakov, Dmitri B. Strukov, & Jabez J. McClelland. Nature Communications 8, Article number: 1972 (2017) doi:10.1038/s41467-017-02116-9 Published online: 07 December 2017

This is an open access paper.

It might be my imagination but it seemed like a lot of papers from 2017 were being publicized in early 2018.

Finally, I borrowed much of my headline from the NIST’s headline for its news release, specifically, “Thanks for the memory,” which is a rather old song,

Bob Hope and Shirley Ross in “The Big Broadcast of 1938.”

You have till June 30, 2016 to submit your NanoArt and/or art-science-technology paper

A June 9, 2016 news item on Nanotechnology Now features a call for submissions to a NanoArt festival,

The 4th International Festival of NanoArt An Art-Science-Technology special session will be hosted in Cluj-Napoca, Romania, by Babes-Bolyai University between September 8 – 14, 2016 in parallel with the 11th International Conference On Physics Of Advanced Materials (Nanomaterials).

The artworks will be shown in the Hall of Transilvania Philharmonic Cluj-Napoca (…). The exhibition is curated by artist and scientist Cris Orfescu, founder of NanoArt 21 and artist Mirela Suchea, PhD, researcher in the field of nanostructured materials synthesis. The previous editions of the festival were held in Finland, Germany, and Romania. For additional Information, visit: nanoart21.org/nanoart_festival.html

Call for Papers

An Art-Science-Technology special session will be held during the 11th International Conference on Physics of Advanced Materials (ICPAM 11) between 8th to 14th of September, 2016 at Babes-Bolyai University of Cluj-Napoca, Romania.

This session focuses on presentations (oral and poster) related to NanoArt, Scientific Photography (microphotography, bio, medical, space, environmental, etc.), Digital Art, Video Art, Computer Graphics, Computer Animation, Game Design, Interactive Art, Net Art, Fractal Art, Algorithmic Art, Virtual Reality, Math Art.

Abstract Submission – Deadline June 30th 2016. Authors are invited to submit a summary of no more than 2000 characters (including spaces) using Conference Online Management System (www.abstractcentral.ro). …

According to the submission page, there are a few more rules,

 

  • The presenting author must be a paid registrant.
  • The authors can choose the presentation form of the paper among oral presentation or poster presentation.
  • Members of the Advisory Board can decide to change the final presentation form of the proposed contribution.
  • Authors will be notified of acceptance and mode of presentation of their papers before August 15, 2016.

 

There is also a call for artworks, from the 4th International Festival of NanoArt webpage,

THE 4th INTERNATIONAL FESTIVAL OF NANOART
Open to All Artists and Scientists

Submission deadline July 15, 2016

The following are the general directions for artwork submission. For selection, the artists can send for free up to 5 images in .jpeg format at a resolution of 72 dpi with the longest dimension of maximum 800 pixels. Each image should be sent with an entry form (click to download). The image(s) and entry form(s) should be sent by e-mail to info@nanoart21.org no later than July 15, 2016. The artists will receive the acceptance email by July 30, 2016 and they should submit high resolution (300dpi) .jpeg files of the accepted works in A3 format size (29.7cm x 42cm or 11.69in x 16.54in) no later than July 30, 2016. The selected images will be sent in digital format to the host venue where they will be printed, matted, and framed. The cost TBA should be paid (see ‘Buy Now‘ button bellow) at the time when artists send the high resolution files. After the event, the works may be exhibited in different venues for continuing education. A travel exhibition to different venues is always a possibility. If artists would like to have their print, they will have to pay for handling and shipping.

The festival will be promoted on different venues online, nanoart21.org contacts, social media, word-of-mouth. The artists could also promote the competition on their websites and other venues. All selected artworks will be shown in a multimedia presentation on the nanoart21.org festival’s page.

Copyright of entered artworks remains with the artist who agrees by submitting his/her works to grant permission to nanoart21.org and Cristian Orfescu to use the submitted material in exhibits, on the nanoart21.org web site, and other media for marketing and printing for off line marketing. Your permission to display the entry for the festival and later online and in the archives cannot be reversed and its use or removal is entirely at the discretion of nanoart21.org.

After the artworks have been accepted for the festival, the artists can pay 20 Euro/artwork for printing, framing, matting, and exhibition by … .

Good luck with your submissions.

Directa Plus unleashes graphene-based mobile decontamination units

I’ve been covering Directa Plus stories for a little over a year now (my Dec. 17, 2014 posting titled: Water purification, Italy, Romania, and graphene and my May 25, 2015 posting titled: A GEnIuS approach to oil spill remediation at 18th European Forum on Eco-innovation. The product that most interests me is the graphene-based environmental decontamination unit, Grafysorber. Happily it is now being offered commercially according to a Dec. 18, 2015 Directa Plus press release found on Business Wire (and a PDF news release, you will need to download, can be found on the company’s website here),

Directa Plus (“Directa or “the Company”), one of the largest producers and suppliers of graphene for use in consumer and industrial products, is pleased to announce the global commercial launch of the Grafysorber™ Decontamination Unit, the world’s first graphene-based system for tackling environmental emergencies such as oil spills. The launch follows successful industrial remediation activities conducted in Italy and Romania.

The Company is also pleased to announce that Biocart S.r.l., an Italian company engaged in the research, development and industrialisation of next-generation materials and solutions for the mitigation of natural disasters and environmental remediation, has purchased the first three mobile units.

Giulio Cesareo, Chief Executive Officer of Directa, said: “We are pleased to launch the Grafysorber™ Decontamination Unit that will enable a prompt and effective response to a potential catastrophe such as an oil spill – and so help avoid a major environmental disaster. Due to the mobile nature of the unit, it can be stored nearer to an area where an event may occur, thereby reducing the time and costs ordinarily associated with the transportation of a solution.”

The Grafysorber™ Decontamination Unit contains a proprietary and patented plasma machine that is able to produce on site all the Grafysorber™ needed to clean up water contaminated with the harmful hydrocarbons contained in oil spills. As it is a mobile unit, it can be quickly deployed to the site of the spill.

During 2015, two industrial remediation activities have been carried out with GrafysorberTM, treating approximately 35,000m3 of water contaminated with petroleum hydrocarbons. Less than 5g/m3 of GrafysorberTM were able to remove the hydrocarbon contaminants, reducing the concentration from 550mg/l to a safe level of approximately 0.5mg/l, with a significant cost reduction of 50-60% compared with traditional technologies.

Grafysorber™ is a sustainable product as it enables the recovery and recycling of the adsorbed oils; it is recyclable; and it does not contain any toxic substances. The ability to produce the graphene on site and in the right quantity renders it a very cost-effective solution compared with conventional solutions. Grafysorber™ has received approval from the Ministry of Environment in Italy and in Romania.

“This is an important step for Directa Plus as we unveil another significant application for graphene-based solutions. It has been achieved due to our technical strength and proprietary process for producing graphene in various forms in a cost effective manner. The ability of the Grafysorber™ Decontamination Unit to produce all the graphene necessary to purify the contaminated water directly at the site of use can be easily replicated and applied to other emergency scenarios. The initial demand that we have already received for this product provides further evidence that graphene has left the laboratory and is ready for mass adoption,” added Giulio Cesareo.

I look forward to hearing more about this product as it is put into use.

Water purification, Italy, Romania, and graphene

I’m hauling some of the material out of my backlog for publication as I clear the decks for 2015 including this Dec. 17, 2014 news item on Nanowerk about water remediation,

Graphene Plus materials have an amazing capacity for adsorbing organic pollutants such as hydrocarbons from water, soils and air. Directa Plus has already certified the removal capacity of Graphene Plus for floating oils in water and has obtained the approval of the Italian Environmental Ministry for the use these products in oil spills clean-up activities. Graphene Plus is also object of GEnIuS (Graphene Eco Innovative Sorbent), a Directa Plus’ project co-founded by European Union within the Eco-Innovation initiative. The project aims to launch into real markets an innovative solution for water treatment based on graphene.

A Dec. 17, 2014 Directa Plus press release, which originated the news item, describes how a Romanian company has tested the effectiveness of Graphene Plus for water remediation,

Directa Plus has found in SetCar – a Romanian company with fourteen years of activity in decontamination and disposal of hazardous waste – an ideal partner for testing environmental applications of Graphene Plus materials, especially in environmental remediation.

Since summer 2014, SetCar has tested on laboratory scale Graphene Plus materials as adsorbents for different type of organic pollutants. The most impressive laboratory results have been obtained with Grafysorber™ and have encouraged pilot test in hydrocarbons removal from contaminated waters.

The first treatment project started on 14th October, 2014, inside a Romanian former refinery site, containing a basin with about 16 500 m3 of water contaminated with petroleum hydrocarbons. The initial hydrocarbons concentration in water was about 56 ppm (3 drops of oil inside 1 litre of water), which means more than 1 tonne of pollutants that must be removed. The hydrocarbons maximum concentration necessary for the discharge of treated water into superficial aquatic ecosystems is 5 ppm.

“5 g/m3 of Grafysorber™ were able to bring the hydrocarbons concentration down to 1 ppm or lower and in only 10 minutes of contacts with the contaminated water! – says Eng. Covaci Melchisedec, Technical Manager of SetCar SA – We worked with a flow rate of 16 m3/h (daily flow rate of 360 -390 m3) in 2 consecutive batches of 4 m3. The total quantity of Grafysorber™ used in this project, which is now concluded, was 80 kg. In next projects, we have planned to implement the productivity of our treatment plant for low concentration hydrocarbons removal till 50 m3/h.”

Giulio Cesareo, President and CEO of Directa Plus shows his satisfaction for this collaboration and says “Our company needs partners such as SetCar SA. Setcar SA has a solid experience in decontamination field but, at the same time, a consolidate team of more than 50 engineers. Thanks to SetCar pilot test we obtained the real evidence that Grafysorber™ is an effective solution for decontamination of water containing hydrocarbons at low concentration”.

The Commercial Director of SetCar SA, Sandu Balan adds “We want to explore Graphene Plus potentiality in removing different type of pollutants from real contaminated water, soils and air and use it in other international projects of decontamination”.

Directa Plus, founded in 2005 and with headquarters in the ComoNext Science and Technology Park in Lomazzo (CO), is a technology company pursuing the development and marketing innovative manufacturing processes for the production of a new generation of nanomaterials targeting existing global markets. On June 23rd, 2014, Directa Plus opened its “Graphene Factory”, a new industrial centre distinguished for being the largest production plant in Europe of pristine graphene nanoplatelets, based on a patented and granted technology and designed according to a modular, replicable and exportable logic. The first module has 30-tonnes per year production capacity. To date, Directa Plus holds 26 granted patents and 19 patents pending. …

Setcar S.A. Established in 1994 as a joint stock company with entirely Rumanian private capital, the company is been developing since 2000 the range of services aimed to solve the environment issues, having as permanent concern the supply of a complete range of services, from chemical analyses for waste identification or, by creating new technologies, up to hazardous waste disposal or bringing the contaminated site to initial condition. …

You can find out more about Directa Plus here and about SetCar here (you will need your Romanian language skills as I cannot find an English language version of the site).

Nature imitates art at Northeastern University (US)

It’s an intriguing mental exercise trying to flip the tables on nature as an inspiration for art to start discussing ‘artmimetics’ as they seem to be doing at Northeastern University (Boston, Massachusetts, US), according to a Dec. 11, 2013 news item on Azonano,

There are exam­ples of art imi­tating nature all around us—whether it’s Monet’s pastel Water Lilies or Chihuly’s glass­blown Seaforms, the human con­cep­tion of nat­ural phe­nomena daz­zles but does not often surprise.

Yet when asso­ciate pro­fessor of physics Latika Menon peered under the elec­tron micro­scope last fall, she dis­cov­ered the exact oppo­site. Instead of art imi­tating nature, she found nature imi­tating art.

The Dec. 10, 2013 Northeastern University news release by Angela Herring, which ‘inspired’ the news item, describes how Menon and her colleagues came to reverse the inspirational direction,

Menon grew up in the eastern region of India and was vaguely familiar with a cul­tural dance from the western state of Rajasthan known as the Bhavai pot dance. Nimble dancers sway their hips as a tall stack of wide-​​bellied pots bal­ances gin­gerly atop their heads. Back in the lab at North­eastern, Menon’s team recently cre­ated  gal­lium nitride nanowires, which bore a striking resem­blance to that stack of pots.

What’s more, a post­doc­toral research asso­ciate in Menon’s lab, Eugen Panaitescu, jumped on the band­wagon with a cul­tural art ref­er­ence of his own. Panaitescu, who hails from Romania, also saw his country’s famous End­less Column reflected in the nanowires. Ded­i­cated to the fallen Romanian heroes of World War I, Con­stantin Brancusi’s 96-​​foot-​​tall mono­lith is con­structed of 17 three-​​dimensional rhom­buses, peri­od­i­cally wavering from a wider cir­cum­fer­ence to a nar­rower one.

The news release goes on to explain more about applications using gallium nitride and why Menon’s insight may prove useful in developing new uses for gallium nitride nanowires,

… Gal­lium nitride is used across a range of tech­nolo­gies, including most ubiq­ui­tously in light emit­ting diodes. The mate­rial also holds great poten­tial for solar cell arrays, mag­netic semi­con­duc­tors, high-​​frequency com­mu­ni­ca­tion devices, and many other things. But these advanced appli­ca­tions are restricted by our lim­ited ability to con­trol the material’s growth on the nanoscale.

The very thing that makes Menon’s nanowires beau­tiful rep­re­sents a break­through in her ability to process them for these novel uses. She deposited onto a sil­icon sub­strate small droplets of liquid gold metal, which act as cat­a­lysts to grab gaseous gal­lium nitride from the atmos­phere of the exper­i­mental system. The net forces between the tiny gold droplet, the solid sub­strate, and the gas cause the nanowire to grow in a par­tic­ular direc­tion, she explained. Depending on the size of the gold cat­a­lyst, she can create wires that exhibit peri­odic serrations.

“It first tries to grow out­ward, but that gives the gold a larger sur­face area,” she said. “So now the wire gets pulled in the inward direc­tion, and then the gold gets a smaller sur­face area, so it grows out­ward again.” This inward and out­ward growth repeated itself again and again to create a peri­odic struc­ture nearly 6 mil­lion times smaller than the end­less column and is sig­nif­i­cantly more promising for its use in advanced devices.

“That there is very little imple­men­ta­tion of nanowire tech­nology in elec­tronics or optical devices is due to the fact that it’s very hard to con­trol their shape and dimen­sions,” said Menon. But now that she has a very simple way of con­trol­ling growth, the next step is to con­trol the size of the cat­alytic droplet with which she starts.

Another advan­tage of Menon’s approach is using what Panaitescu called “macro­scopic tech­niques” to create nanoscale mate­rials, thus making it scal­able and inex­pen­sive. “We just con­trol a few para­me­ters and then leave it, let it do it’s nat­ural thing,” explained Menon.

Here’s an image the researchers have supplied to illustrate their insights and their work,

Depending on the size of the gold cat­a­lyst used to make them, Latika Menon’s nanowires will exhibit peri­odic grooves that resemble common motifs in art. Images cour­tesy of Latika Menon. - See more at: http://www.northeastern.edu/news/2013/12/menon-nanowires/#sthash.LkgJU4es.dpuf

Depending on the size of the gold cat­a­lyst used to make them, Latika Menon’s nanowires will exhibit peri­odic grooves that resemble common motifs in art. Images cour­tesy of Latika Menon. – See more at: http://www.northeastern.edu/news/2013/12/menon-nanowires/#sthash.LkgJU4es.dpuf

I’m not sure I can connect the  imagery in this pot dance video (it does show some pretty astonishing feats of balance) with any of the images from Menon’s lab but sometimes the source of an inspiration is not readily accessible to those who are not amongst the inspired or perhaps there other versions of the dance that make it more obvious to an untrained eye,

Here’s an image of the other artistic inspiration, Constantin Brancusi’s Endless Column found on Dr. Cătălina Köpetz’s (University of Maryland) webpage featuring Brancusi’s work along with this quote from him “Create like a god, comand like a king, work like a slave.”

The Endless Column, Târgu Jiu, România  [downlaoded from http://terpconnect.umd.edu/~ckopetz/brancusi.htm]

The Endless Column,
Târgu Jiu, România [downlaoded from http://terpconnect.umd.edu/~ckopetz/brancusi.htm]

Interestingly, Dr. Köpetz is a social psychologist working in the university’s Center for Addictions, Personality, and Emotion Research.

For anyone who’d like to read more about Menon’s work, here’s a link to a webpage featuring a PDF selection of her papers and a citation for her latest paper on the work described in the news release,

Vapor–liquid–solid growth of serrated GaN nanowires: shape selection driven by kinetic frustration by Zheng Ma, Dillon McDowell, Eugen Panaitescu, Albert V. Davydov, Moneesh Upmanyu and Latika Menon, Physics Faculty Publications (2013)

Compound semiconducting nanowires are promising building blocks for several nanoelectronic devices yet the inability to…

The paper is open access although you will have to click a few times to retrieve it.