If you need assistance, please send an email to forum at 4hv dot org. To ensure your email is not marked as spam, please include the phrase "4hv help" in the subject line. You can also find assistance via IRC, at irc.shadowworld.net, room #hvcomm.
Support 4hv.org!
Donate:
4hv.org is hosted on a dedicated server. Unfortunately, this server costs and we rely on the help of site members to keep 4hv.org running. Please consider donating. We will place your name on the thanks list and you'll be helping to keep 4hv.org alive and free for everyone. Members whose names appear in red bold have donated recently. Green bold denotes those who have recently donated to keep the server carbon neutral.
Special Thanks To:
Aaron Holmes
Aaron Wheeler
Adam Horden
Alan Scrimgeour
Andre
Andrew Haynes
Anonymous000
asabase
Austin Weil
barney
Barry
Bert Hickman
Bill Kukowski
Blitzorn
Brandon Paradelas
Bruce Bowling
BubeeMike
Byong Park
Cesiumsponge
Chris F.
Chris Hooper
Corey Worthington
Derek Woodroffe
Dalus
Dan Strother
Daniel Davis
Daniel Uhrenholt
datasheetarchive
Dave Billington
Dave Marshall
David F.
Dennis Rogers
drelectrix
Dr. John Gudenas
Dr. Spark
E.TexasTesla
eastvoltresearch
Eirik Taylor
Erik Dyakov
Erlend^SE
Finn Hammer
Firebug24k
GalliumMan
Gary Peterson
George Slade
GhostNull
Gordon Mcknight
Graham Armitage
Grant
GreySoul
Henry H
IamSmooth
In memory of Leo Powning
Jacob Cash
James Howells
James Pawson
Jeff Greenfield
Jeff Thomas
Jesse Frost
Jim Mitchell
jlr134
Joe Mastroianni
John Forcina
John Oberg
John Willcutt
Jon Newcomb
klugesmith
Leslie Wright
Lutz Hoffman
Mads Barnkob
Martin King
Mats Karlsson
Matt Gibson
Matthew Guidry
mbd
Michael D'Angelo
Mikkel
mileswaldron
mister_rf
Neil Foster
Nick de Smith
Nick Soroka
nicklenorp
Nik
Norman Stanley
Patrick Coleman
Paul Brodie
Paul Jordan
Paul Montgomery
Ped
Peter Krogen
Peter Terren
PhilGood
Richard Feldman
Robert Bush
Royce Bailey
Scott Fusare
Scott Newman
smiffy
Stella
Steven Busic
Steve Conner
Steve Jones
Steve Ward
Sulaiman
Thomas Coyle
Thomas A. Wallace
Thomas W
Timo
Torch
Ulf Jonsson
vasil
Vaxian
vladi mazzilli
wastehl
Weston
William Kim
William N.
William Stehl
Wesley Venis
The aforementioned have contributed financially to the continuing triumph of 4hv.org. They are deserving of my most heartfelt thanks.
Registered Member #65
Joined: Thu Feb 09 2006, 06:43AM
Location:
Posts: 1155
I have looked into the research on drug-resistant bacterial decontamination, and recent FDA approvals for tumor treatment trials.
Some papers mention a "sinusoidal 50 Hz field with amplitudes of the flux density B = 0.3 to 4.7 mT" can affect cell mitotic processes.
Specifically, I am interested in whether anyone has tried a low-cost mechanically spun Halbach sphere to generate a non-static field. The Cylinder method is not as confined, but may also work:
Any interesting apparatus variant suggestions are welcome as always...
Registered Member #162
Joined: Mon Feb 13 2006, 10:25AM
Location: United Kingdom
Posts: 3140
Wouldn't it be easier to use something like a Helmholtz coil with 50 (60) Hz mains? 0.3 to 4.7 mT is not a very strong flux density, should be easily achieved.
Registered Member #96
Joined: Thu Feb 09 2006, 05:37PM
Location: CI, Earth
Posts: 4061
This is news to me, I was unaware of the laws of physics having changed. Low power ie 50Hz fields aren't strong enough to affect biological processes, higher frequency and power ie 2.45 GHz at 100mW/cm2 do however by direct heating and denaturing of proteins.
Registered Member #543
Joined: Tue Feb 20 2007, 04:26PM
Location: UK
Posts: 4992
Conundrum wrote ...
This is news to me, I was unaware of the laws of physics having changed. Low power ie 50Hz fields aren't strong enough to affect biological processes, higher frequency and power ie 2.45 GHz at 100mW/cm2 do however by direct heating and denaturing of proteins.
-A
There are political-economic magnetic fields that affect no one and nothing, but have the potential to affect cell-phone and power distribution share prices - and the careers of scientists who unwisely suggest there might be a danger in them - and then there is all the rest, where fields alternating at as low as 0.3 Hz are allowed to affect the properties of living cells:
Registered Member #65
Joined: Thu Feb 09 2006, 06:43AM
Location:
Posts: 1155
@Conundrum Indeed, the technology does sound somewhat dubious, but the number of independent studies seems to earn some review. The field apparently interferes with cellular division processes, and has been shown to be effective against rapidly dividing cells.
@Sulaiman Thanks for the design tip, I may indeed try to replicate low the level exposure experiment to verify and compare data. However, the exposure confinement area needs to be quite fine (5cm diameter), and I am not sure if that winding form would work.
@Proud Mary Governments shouldn't care about a few nematodes' fate if it can potentially help people with cancer. The FCC does seem to make some arbitrary decisions sometimes... Perhaps the FDA approval may create a bureaucratic paradox.
Registered Member #2529
Joined: Thu Dec 10 2009, 02:43AM
Location:
Posts: 600
Well, I've built Halbach arrays before, I generated about 1 Tesla.
Generating a field the size you're talking about doesn't even need Halbach arrays, you just need iron and virtually any permanent magnet.
Halbach arrays are a bit of a pain BTW, they are constantly trying to push themselves apart. Iron core structures are much easier, they usually hold themselves together pretty much; so you should avoid Halbachs wherever possible. Also Halbach arrays lose a little of the total field when they are assembled; they're more intense, but the total field is reduced, basically because the magnets are fighting each other.
This site is powered by e107, which is released under the GNU GPL License. All work on this site, except where otherwise noted, is licensed under a Creative Commons Attribution-ShareAlike 2.5 License. By submitting any information to this site, you agree that anything submitted will be so licensed. Please read our Disclaimer and Policies page for information on your rights and responsibilities regarding this site.