Category: Science > Physics
Asked by: diaspora-ga
List Price: $30.00
03 Mar 2006 11:34 PST
Expires: 02 Apr 2006 12:34 PDT
Question ID: 703293
Can the material demron protect against concentrated microwave or emf surges or reduce effects of same?
Answered By: hedgie-ga on 03 Mar 2006 16:37 PST
Newspaper story: http://news.bbc.co.uk/2/hi/science/nature/2478465.stm Patent application for Demron http://appft1.uspto.gov/netacgi/nph-Parser?Sect1=PTO1&Sect2=HITOFF&d=PG01&p=1 &u=%2Fnetahtml%2FPTO%2Fsrchnum.html&r=1&f=G&l=50&s1=%2220020043631%22.PGNR.&O S=DN/20020043631&RS=DN/20020043631 Claim DemronTM suits are constructed from a unique nanotechnology that far surpasses the effectiveness (or ineffectiveness) of current nuclear-biological-chemical (NBC) suits that only protect against radioactive particulate sources. http://www.radshield.com/ Conclusion: There are no measurment to support the claims. The terms and sxpression in claims and publicity articles sounds like a pseudo-science, for example "radioactive particulate sources" I would not spend money on it. Any material will 'reduce the effects'. Issue is : Is the ratio od density to protection any better for this material then for any other. By density we mean the mass per volume. Lead has high density. Any metal will shield microwave or emf and will be more effective (per unit od mass) then polymer (which Demron claims to be). Hedgie
rated this answer:
and gave an additional tip of:
Didn't just give a link. Gave a contrarian opinion to the hype. I will look for other views. Hey, the guy gave me something to go on.
From: hfshaw-ga on 08 Mar 2006 12:54 PST
Actually, there *are* published (if you accept conference proceedings as "published") measurements to support at least some of the claims made for Demron. Both Batelle Pacific Northwest National Labpratory and Lawrence Livermore National Laboratory (LLNL) have made measurements of the attenuation of photons (x-rays and gamma rays), as well as electrons (beta particles) of Demron and compared these results to other standard radiation shielding materials. These reports are available at the manufacturer's website at http://www.radshield.com/research_results.cfm. The LLNL report formed the basis for a conference paper and presentation at the 2003 American Nuclear Society meeting in San Diego (paper also available at the above URL, and also at the LLNL on-line library at http://www.llnl.gov/tid/lof/documents/pdf/246495.pdf). The bottom line is that the radiation-attenuation characteristics of Demron are very similar to those of the element tantalum. Plots of the mass attenuation coefficients as a function of energy for these two materials are very similar.
From: hfshaw-ga on 08 Mar 2006 12:59 PST
...continuation of previous comment All that having been said, the your question asked about shielding microwave radiation and the electric fields associated with an EMP. Unless Demron is a good electrical conductor (and it doesn't seem like this is the case), it will not be particularly effective at shielding these types of sources. Attenuation of microwave radiation in materials occurs by very different mechanisms than does attenuation of higher energy photons and electrons.
If you feel that you have found inappropriate content, please let us know by emailing us at firstname.lastname@example.org with the question ID listed above. Thank you.
|Search Google Answers for|