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(Credit: Jonathan Pankau/Wikimedia Commons.)

Last week we had about a report from researchers at Georgia Tech who show how concrete rubble from the earthquake can be safely recycled into stronger concrete using local resources and manual production and mixing techniques.

As a follow-up to this, I want to highlight an NPR story first broadcast yesterday regarding the challenge of the dealing with the rubble and how Haitians are already using manual rubble-crushing equipment brought in from Swaziland and recycling it:

“The machine’s parts are carried up the labyrinth of tiny walkways. Then the machine is reassembled and the crushing begins. It’s hard work, says Amos Laguerre, who makes about $5 a day cranking.

It takes three men to get the job done; two crank the handles, while the third drops boulder-size debris between the metal crushers. Singing helps the men get through the mind-numbing labor.

The crumbled rubble is collected in buckets. Sand and gravel are separated into plastic bags. On a good day, the crew fills 125 bags, about 5 cubic meters.

No one says this is a solution to the city’s rubble problem, but it is making a difference in small neighborhoods like Delmas 62. The bags of recycled rubble are mixed with cement and poured to make the foundations of temporary wooden shelters CRS gives to residents.”

As Georgia Tech’s experts point out, however, unless some simple-to-implement standards for concrete composition are adopted, the new concrete will likely be far below minimum construction standards and prone to new earthquake damage.

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Ceramist, materials engineer and university-business technology partnership expert Beth Judson and her husband, Jim, were killed Tuesday when their plane crashed north of Tupelo, Miss.

The news of her death is startling to the ceramics and materials science community who had just been meeting and catching up with Judson last week during the ACerS Annual Meeting and MS&T’10 conference in Houston.

Besides her science and engineering work, Judson was also known for her efforts on the Alfred University Board of Trustees, and with the Engineering Accreditation Commission and the Board of Directors of the Accreditation Board for Engineering and Technology. She also had just completed her term as president of ACerS/National Institute of Ceramic Engineers.

Judson had been working for the University-Industry Demonstration Partnership, an organization of universities and businesses, sponsored by the National Academies, that seeks “to enhance the value of collaborative partnerships between university and industry in the United States.”

A biography at the UIDP website contains this biographical information:

[Prior to coming to UIDP], she was general manager for Verco Materials LLC, a Georgia Tech VentureLab company formed to commercialize technology to pressureless sinter boron carbide, a critical ceramic armor material. Beth has also worked on other Georgia Tech projects, including a manual on forming and operating research centers, and organizing a site visit for a science and technology center proposal to the National Science Foundation on biologically enabled advanced materials and micro/nano-devices. For several years she was director of industry relations for Yamacraw, a Georgia economic development initiative in the form of a multi-university broadband chip design research center. She also has over ten years of industrial experience with Alcoa Chemicals, Technical Ceramics Laboratories and Applied Ceramics, in sales, product management and research.

Dr. Judson received a B.S. in ceramic science and a B.A. in mathematics magna cum laude from Alfred University in 1982, and M.S. and Ph.D. degrees in ceramic engineering from the Georgia Institute of Technology in 1991 and 1999, respectively.

The UIDP also mentions that she was a member of the Boards of Trustees of Southern Catholic College, as well as a member of the Advisory Boards of the School of Materials Science and Engineering at Georgia Tech and Clemson University,  and the Alfred University Women’s Leadership Center.

Colleague and friend Kathleen Richardson, a professor at Clemson, notes in an email sent to me this afternoon, that, “Beth was truly an inspiration to all who worked with her — loving, giving and committed to whatever cause she was leading.  She contributed greatly to all parts of our ceramic engineering profession — but perhaps has made the most impact on the many women in engineering she touched and support of their future leadership opportunities. She was a gifted woman, dedicated wife and mother and a dedicated supporter of ceramic engineering and science education.”

John Marra, another one of Judson colleagues in ACerS writes, ”Beth was one of those rare individuals who could electrify a room just by walking in. She was a tireless advocate for the ceramics profession and always helped encourage students and young professionals.  It is truly a sad day;  the community has lost one of its brightest lights.”

UPDATE 1: The Atlanta Constitution has just published this story about the Judsons.

UPDATE 2: A vigil and visitation Service will be held Sunday, Oct. 31, 2010 at 7:00 p.m. at St. Brigid Catholic Church, 3400 Old Alabama Rd, Johns Creek, Georgia 30022 (www.saintbrigid.org). The funeral mass will be the following day, Nov. 1 at 12:00 pm at St. Brigid, followed by a reception at Country Club of Roswell, 2500 Club Springs Drive, Roswell (www.ccroswell.com). At the family’s request, memorial donations can be made, in lieu of flowers, to the Society of St. Vincent de Paul at St. Brigid , which Jim and Beth strongly supported and embraced. The Judson family has also issued this press release (PDF).

Also, Alfred University has posted this announcement.

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It’s great to see that a large number of schools that we reference in this blog made it to Bloomberg BusinessWeek’s new list of the top 25 “best bargain” universities, and hopefully this will be a shot in the arm to some of the smaller schools, such as the Colorado School of Mines (#1) and  Missouri S&T (#13).

Other schools with well-known materials-oriented programs include Georgia Tech (#2), University of Michigan (#6), Virginia Tech (#7), Texas A&M (#9), Purdue (#12) and University of Florida (#15).

The story – “Cheap Schools That Pack an ROI Punch” – was prepared by Businessweek based on an analysis of earnings data for college graduates. The source data came from PayScale, a salary comparison and benchmarking service. Using this information, Businessweek calculated a 30-year net return on investment for more than 500 colleges and universities.

According to the publication, these schools “boast a 30-year net return on investment that ranges from about $600,000 to more than $1.1 million, an improvement of 56 percent to 187 percent over the average for the entire sample. All of them sport decent graduation rates, too - in most cases, well above the 58 percent average.”

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A group of researchers representing several institutions report in Science they have gained new abilities to “print” graphene oxide-based nano-scale replacements for IC wiring and some semiconductor devices using a method that employs an atomic force microscope to act as a printer head do the detailed work of tuning the conductivity of the material in precise patterns.

GO is an interesting material because it is more resilient to mechanical stresses than standard graphene. Furthermore, in a reduced form, GO becomes a semiconductor (reduced GO – rGO – has a conductivity that is 33,000 times higher than that of doped hydrogenated amorphous silicon).

The innovation the researchers are pioneering is the use of a heated AFM tip on GO to precisely create nanoribbons of rGO. The group – from Georgia Tech, Naval Research Lab, Chung Ang University (Korea), University of Illinois at Urbana-Champaign and CNRS-Institut Néel (France) – didn’t invent thermochemical nanolithography, but the were the first to employ TCNL, via an AFM probe tip, to reduce patterned regions of GO simply by varying the temperature of the tip.

They tested their TCNL method on both GO flakes on a SiO_x/Si substrate and large-area GO films (>15 mm²) formed from epitaxial graphene grown on the carbon face of silicon carbide. They were able to print the rGO nanoribbons at a rate of about  2 µm per second, forming ribbons as narrow as 25 nm. They were able to demonstrate the formation of nanoribbons in zigzag and cross-shaped patterns.

What’s down the road for this? The researchers envision graphene nanoelectronics made by using large arrays of independent heated probe tips that would “print” nanostructures on wafer-scale areas at high speed.

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ACerS member Zhong-Lin Wang continues to make interesting progress on developing nanowire power generators and other energy-scavenging devices, and recently has demonstrated a nanogenerator that can be powered by the motion of a beating heart or the flexing of diaphragms and lungs.

When I last wrote about Wang in early 2009, he was demonstrating a “flex charge pump” generator constructed of zinc-oxide piezoelectric fine wires that measure three to five microns in diameter and 200 to 300 microns in length. Back then, he was thinking these tiny generators could be used in self-powered wireless sensing systems that gather, store and transmit data. He imagined then that his method could be scaled down to a nano size.

Since that time, however, it appears that Wang, a professor at Georgia Tech, has also become more interested in applications involving biomedical sensors. In fact, in a paper published in Advanced Materials, he and his fellow researchers report on what may be the first in vivo testing of nanoscale power generators activated by the breathing and heart beat of a rat. This could be a significant step forward in the creation of self-powered implanted nanodevices that could, for example, monitor blood pressure or blood glucose levels. (It should be noted that a group of Cleveland-area researchers reported in July 2009 on a larger-scale in vivo generator activated by a rabbit’s quadriceps).

Wang and his team sealed zinc-oxide nanowires in a polymer. The polymer served as a shield to the rat’s body fluids and to be a barrier to outside electrical sources. They then glued the 2 mm x 5 mm rectangular unit to the rat’s diaphragm muscle. The breathing motion generated 4 picoamps of current at a potential of 2 millivolts. Even more power was generated when the unit was glued to the rat’s heart: 30 picoamps at 3 millivolts.

Wang acknowledges that, while significant, this new work is more of a interim step than a final achievement, and that much more power is going to be needed for actual sensors. But Wang notes that his group has also figured out how to integrate a large number of nanowire energy harvesters into a single 4 mm² power source (a vertically integrated nanogenerator, or VING) and has demonstrated the feasibility with a self-powered nanowire pH sensor and a nanowire UV sensor.

Interestingly, Wang has also demonstrated a hybrid generation system that could be used in vivo. This system, used to power a UV sensor combines a piezo nanogenerator with a biofuel cell that scavenges biochemical energy (glucose/O₂).

Apparently the next step if to do in vivo testing of a VING–sensor system.

He is another video featuring an interview with Wang from about a year ago

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