|Ken Novak's Weblog
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Friday, August 12, 2005
Study of super-hard ceramics: "A discovery reported in the August 5 issue of Science could speed the design of materials that approach the hardness of diamond yet remain supple enough to be worked like metal. In a massive computer simulation involving 128 computer processors and nearly 19 million atoms, materials scientist Izabela Szlufarska of the University of Wisconsin-Madison and colleagues at University of Southern California demonstrated the precise atomic mechanisms that explain why "nanostructured" ceramic materials-some of the hardest substances known-also exhibit unusual pliability.
Unlike other exceptionally hard materials, these advanced ceramics tend to bend rather than break, meaning they could be shaped into extremely long-lasting yet lightweight parts for everything from automobile engines and high-speed machining tools to medical implants in the body.
Simulations can help to answer this by providing a level of detail unavailable to experiments. Using atomic-scale simulations, the team observed for the first time how atoms moved and interacted as a super-hard ceramic deformed under stress. The advance has not only provided unprecedented insight into the properties of these materials, but also a tool that researchers can use to systematically nano-engineer them. ..
The researchers next want to learn how to control the crossover point so as to engineer greater hardness into nano-crystalline silicon carbide without compromising pliability. For example, they could vary the volume of the grain boundaries or the size of the grains. Impurities, or dopants, might also be added to the grain boundaries to make the material stronger. Key to it all is the enormous computing power that allows scientists to simulate the material’s atomic details. "The experiments and devices have become smaller and smaller, while the simulations have grown larger and larger," says Szlufarska. "This is a unique time when the leading edge of materials design is exactly at the same length scale where fully atomic simulations are possible." " 2:21:50 PM
Towards a green nanotechnology: Review of the issues and early studies. "nanotechnology has been the subject of projections concerning its possible environmental risks well before its wide-scale commercialization. Raising such questions when nanotechnology is still in its infancy may result in better, safer products and less long-term liability for industry.
The rapidly developing nanomaterials industry is the nanotechnology that is most likely to affect our lives first. .. In the environmental technology industry alone, nanomaterials will enable new means of reducing the production of wastes, using resources more sparingly, cleaning up industrial contamination, providing potable water, and improving the efficiency of energy production and use. Commercial applications of nanomaterials currently or soon to be available include nano-engineered titania particles for sunscreens and paints, carbon nanotube composites in tires, silica nanoparticles as solid lubricants, and protein-based nanomaterials in soaps, shampoos, and detergents.
The production, use, and disposal of nanomaterials will inevitably lead to their appearance in air, water, soils, or organisms. Research is needed to ensure that nanomaterials, and the industry that produces them, evolve as environmental assets rather than liabilities. Unfortunately, little is known about the potential environmental impacts of nanomaterials...
An encouraging trend is that the methods used to produce nanomaterials often become “greener” as they move from the laboratory to industrial production. Setting aside the issue of nanomaterials’ toxicity, preliminary results suggest that fabricating nanomaterials entails risks that are less than or comparable to those associated with many current industrial activities. ..
It would be naïve to imagine that nanotechnology will evolve without risks to our health and environment. While attempting to halt the development of nanomaterial-inspired technologies would be as irresponsible as it is unrealistic, responsible development of these technologies demands vigilance and social commitment. " 2:05:03 PM
Security Watch: Major Cisco router flaw: "Until recently, the idea of penetrating the Cisco Shellcode via remote access was fanciful. That was before security researcher Michael Lynn stepped up the lectern at this year's Black Hat conference, and after first stumbling through a deliberately faux presentation on VoIP security, proceeded to describe some (but not all) of his research to a skeptical audience. During his presentation, Lynn offered a quick demo of how he could access the root of a Cisco router remotely. ..
by remotely attacking the Cisco IOS Shellcode, you could destroy the instruction set on the hardware that tells the router to turn on again... Following Black Hat, Cisco issued an advisory detailing how flaws in the way older Cisco IOS system process IP6v packets could allow a remote user control of the router. .. 11:23:21 AM
by April, Cisco rolled out a patch via software upgrade. Problem was, neither Cisco nor ISS really explained why the patch was necessary. Applying a patch on a network router often requires that the router be shut down for a given length of time; on a busy network, this requires scheduling, to say the least. Thus, many Cisco clients may not have applied the patch .."
"The Project Puffin seabird camera is now beaming live-streaming video from Matinicus Rock—Maine’s largest colony of Atlantic Puffins and Razorbills. Matinicus Rock is located 22 miles south of Rockland, Maine. .. The robotic camera was funded by grants from MBNA Foundation
and the Disney Wildlife Conservation Fund
. The video signal is beamed by microwave 25 miles to Rockland .. When the [visitor] Center opens, visitors will be able to operate the camera. The camera is an invention of Daniel Zatz of SeeMore Wildlife Systems
of Homer, Alaska.
The camera is set to move every two minutes on an auto tour of 20 preset locations that show seabird habitat on Matinicus Rock. The auto tour includes the murre attraction program that is using decoys to encourage Common Murres to nest on the island.. The camera turns on automatically at 5AM and runs until 9PM- at which time viewers will be able to see the light sending its powerful beams. .. The auto tour also includes two minutes of observation within an underground puffin burrow. Using infrared lighting, viewers will be able to see the growing chick and its parents. This is the first underground video of nesting puffins to be shown on the Internet. " 11:17:36 AM
Internet Scammers Keep Working in Nigeria
: "In Festac Town, an entire community of scammers overnights on the Internet. By day they flaunt their smart clothes and cars and hang around the Internet cafes, trading stories about successful cons and near misses, and hatching new plots. Festac Town is where communication specialists operating underground sell foreign telephone lines over which a scammer can purport to be calling from any city in the world. Here lurk master forgers and purveyors of such software as "e-mail extractors," which can harvest e-mail addresses by the million. Now, however, a 3-year-old crackdown is yielding results, Nigerian authorities say.
Nuhu Ribadu, head of the Economic and Financial Crimes Commission, says cash and assets worth more than $700 million were recovered from suspects between May 2003 and June 2004. More than 500 suspects have been arrested, more than 100 cases are before the courts and 500 others are under investigation, he said." 11:12:31 AM