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Physiology & Medicine / Re: What can cause human skin to look like a zombie's skin?

« on: 04/03/2016 20:02:34 »

Like a meth addict's skin where the blood vessels are dead on the top layers.

The vasculopathy (and consequent ischemia => necrosis ) is not limited to their skin : "meth" causes systemic vascular disease.
Self-inflicted injuries due to formication would be limited to "top layers" of skin.

Generally anaemia would be a more common cause of people looking ghostly-pale, rather than drug abuse ... http://www.who.int/vmnis/anaemia/prevalence/summary/anaemia_data_status_t2/en/

Specifically what chemicals in gas, water, or dust can cause this? Any water additives/contaminants found in supplies? What about acoustic energy?

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Physiology & Medicine / Re: What can cause human skin to look like a zombie's skin?

« on: 02/03/2016 23:18:06 »

The only known cause of parazombism is being undead, recently deceased, or soon to be late.

Like a meth addict's skin where the blood vessels are dead on the top layers.

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Physiology & Medicine / What can cause human skin to look like a zombie's skin?

« on: 02/03/2016 04:26:36 »

Not dry skin but pale, slightly droopy, not overly dry but no sweat, and discolored like someone who died a few minutes ago?

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New Theories / Re: How can ultrasonic neuromodulation remotely control brain activity?

« on: 28/12/2015 15:03:15 »

Duel layered with an insulator made up of a polyhedral vacuum cell structure?

http://m.bonanza.com/listings/masei-610-storm-trooper-motorcycle-helmet-white-st610-s-m-l-xl/251464746?gpid=76984043821&gpkwd=&goog_pla=1&gclid=CjwKEAiA2IO0BRDXmLndksSB0WgSJADNKqqog8VA_UpumQ4elPjiH7gbfI8LUU41_JCjhm7Amt-M6xoCl_Tw_wcB

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Physics, Astronomy & Cosmology / Re: What type of technology can deflect or block high powered acoustics?

« on: 26/12/2015 05:58:28 »

What about this? Or a vacuum ice bucket?
Jem v. the US Navy's latest weapon - Bang Goes th…:

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New Theories / Re: How can ultrasonic neuromodulation remotely control brain activity?

« on: 26/12/2015 05:54:05 »

If this existed would this shield it?
Jem v. the US Navy's latest weapon - Bang Goes th…:

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That CAN'T be true! / Re: Surely the van arken belt would stop humans reaching the moon?

« on: 26/12/2015 05:44:48 »

Funny how the earth was believed flat for 10000 years until the 1st mason said otherwise 500 years ago.foolish eh.

If you really think he was the first to ponder that you are naive and hindering progression.

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Physiology & Medicine / How long does it take 3a-hydroxy-5a-androstan-17-one to convert to DHT?

« on: 24/12/2015 09:16:15 »

On average. Im refering to Epiando the DHEA metabolite or 1 DHEA not 1 Andro
http://prohormonedb.com/view-ingredients.asp?n=3a-hydroxy-5a-androstan-17-one+(Androsterone)&i=266

How about Androsta-3 5-diene-7 17-dione

How long does it take to take action.

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Physics, Astronomy & Cosmology / Re: What type of technology can deflect or block high powered acoustics?

« on: 24/12/2015 09:03:19 »

The attenuation of what?

whatever it is you want to attenuate - presumably ultrasound

The rubber doesn't work well enough at 1 inch and isn't pliable enough to easily work with.

At what frequency and amplitude does it not "work well enough"? What value of attenuation would be "well enough"?

I can't solve a problem if you won't tell me what the problem is, so for the last time before I leave this thread altogether, what frequency and amplitude are you trying to shield against?

What about a noise cancelling helmet do they exist?

No. Only headphones.

It's an LRAD like SARA device. It projects sound that itches, heats, and can remove hair. That's all I know but it has to be similar to ultrasound hair removal.

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Physics, Astronomy & Cosmology / Re: What type of technology can deflect or block high powered acoustics?

« on: 14/05/2015 20:30:30 »

So there you have it (except that the density of water is 10⁶ g/m³) All you need is to define the input amplitude and frequency (i.e. the numbers I keep asking for) and you can calculate the attenuation in decibels.

The attenuation of what? The rubber doesn't work well enough at 1 inch and isn't pliable enough to easily work with. What about a noise cancelling helmet do they exist?

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Physics, Astronomy & Cosmology / Re: What type of technology can deflect or block high powered acoustics?

« on: 13/05/2015 01:17:43 »

The rubber I used is specifically made to absorb ultrasound in anechoic chambers and definately reduces the effect but not enough at only one inch, and the rubber is also a bit too stiff for me to easily work with.

Please provide some numbers. "Not enough" is hardly a design specification.

Blue polyurethane rubber material, single-ply nominally homogeneous layer
Thickness of tile: 10mm, tile dimensions: 300mm by 300mm o
Density of 1.01g/m3, is close to that of water
Specific gravity 1.01
Longitudinal wave speed (1-10MHz)  approx 1500m/s
Acoustic impedance 1.5MRayls
High insertion loss, approximated by 30dB/cm/MHz. Insertion loss at frequencies greater than 2MHz is in excess of 60dB.

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Physics, Astronomy & Cosmology / Re: Can a vacuum helmet be created using an air compressor?

« on: 12/05/2015 10:07:24 »

This depends on the material that the helmet is made of (also how the air compressor works--I would recommend a device designed for decreasing pressure, not increasing it), and how strong a vacuum is required.

There isn't any experimentally attainable perfect vacuum, so really what we are talking about here is reduced pressure. It is easiest to talk about this in terms of orders of magnitude: a household vacuum cleaner can get to about 20% of atmospheric pressure, and a cheap pump can probably achieve pressures about 1% of atmospheric pressure (10^–2 atm). I routinely work with pumps that are about $5000, and can reduce pressure within a thick glass vessel to about 10^–4 atm, and have occasionally used multiple pumps together to achieve pressures of 10^–5 atm. I once worked in a lab that ran experiments in large steel boxes (>3 cm thick walls) under ultra high vacuum of about 10^–10 atm, but that required about $50,000 worth of pumps, sensors and regulation systems. I think deep space can have pressures as low as 10^–20 atm.

Given prior posts of yours I feel compelled to insist that you * DO NOT* try to put your head in anything that you have evacuated--even pressures achievable with a household vacuum cleaner can cause blood vessels to burst in your eyes, ears and face--I promise this is not pleasant!

If instead you wanted to make something akin to a thermos (an inner vessel and an outer vessel, with reduced pressure in between) that wouldn't pose as obvious a risk, but if you have ever broken a thermos you would understand why putting your head in such a contraption could still be very dangerous.

Do Igloo Coolers use reduced pressure as insulation? I think they do but probably not comparable to a steel dewar flask?

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Physics, Astronomy & Cosmology / Re: What type of technology can deflect or block high powered acoustics?

« on: 12/05/2015 09:28:35 »

Let me reword what I'm asking then. If ultrasound was being projected at a high intensity what would happen once it hits a one inch barrier composed of a piezo material? Would all of the sound be converted to electricity or would some make it though if the barrier was made up of silica fibers like shuttle tiles, barium, polyvinylidene fluoride, etc.? At the intensities listed in the charts I posted sound still passes through about a one inch shield of ultrasound absorbing polyrubber specially made by the National Physics Labratory. The rubber I used is specifically made to absorb ultrasound in anechoic chambers and definately reduces the effect but not enough at only one inch, and the rubber is also a bit too stiff for me to easily work with.

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Physics, Astronomy & Cosmology / Re: What type of technology can deflect or block high powered acoustics?

« on: 11/05/2015 21:39:12 »

The references you quote are pretty consistent with everything I've said in this conversation:

damage mainly occurs to the auditory system, so blocking the ears alone will be effective

ultrasound disperses rapidly in air, so distance is effective

impulse pressure has the same effect independent of source, so a conventional explosive would present less danger to the attacker 

Best of all, find out what the attacker is wearing in your diagram. The backscatter from his weapon will be far greater than the forward transmission through a brick wall, so if it works for him, it will work for you. And don't forget the conservation of momentum: find out what he uses to absorb the recoil from his impulse weapon.

You can get a really good blast wave from any high explosive, and if you want to demolish a wall, water or sand bags will intensify the effect.

You can't protect yourself against every conceivable threat but you might take a look at the specification of the Kelvedon "secret nuclear bunker" - also worth a visit! - which was designed to protect my co-workers (I was to be located elsewhere, now demolished) against a direct 10 megaton airburst.

If you are concerned about longterm exposure, stay indoors. Ordinary brick walls and double-glazed windows are extremely effective against ultrasound.

If you are concerned about an actual, ongoing exposure, please measure it and let us know the spectrum and intensity.

Double glazed windows and a dewar vessel I know about. The problem being presented is an attempt to develop protective headwear. The reason I asked about silica sand is because it's what shuttle tiles are made of but I think the tile fibers are fused at a few thousand degrees so I couldn't do that by any normal means. I was interested in piezo materials because if effective I beleive there is film that is pliable. The problem is I need a layer less than 2 inches thick and my initial design calls for a layer of polyhedral vacuum cells within a helmet layer so I was looking for a cheaper alternative to see if I can develop protective headwear. I'm curious how the sound would react to a helmet of piezo material. Specifically I'm wondering could a helmet turned into a passive ultrasonic transducer of sorts be an effective solution.

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Physics, Astronomy & Cosmology / Re: What type of technology can deflect or block high powered acoustics?

« on: 11/05/2015 08:41:45 »

This is the other part of the text.

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Physics, Astronomy & Cosmology / Re: What type of technology can deflect or block high powered acoustics?

« on: 11/05/2015 08:39:04 »

As on your other thread: what is the incoming spectrum and power, and what are your outgoing limits?

Nobody can help you design a solution if you haven't specified the problem, so let's start at the beginning.

In the wise words of my old navigation instructor: "start from where you are, then you won't get lost before you take off."

See this jpeg

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Physics, Astronomy & Cosmology / Re: Could a wall constructed of piezo materials such as barium titanate, or PVDF?

« on: 11/05/2015 08:02:04 »

What about silica sand?

You seem to be proposing solutions, without knowing what the problem is...

How about you state your problem, and then solutions will flow.

Unfortunately, if the ultrasound is purely in your head, then no amount of external shielding will protect you.

Ultrasound directed at over 140DB according to citations from various reports. High intensity ultrasound. Specifically at a intensity and freq that damages hair follicles due to friction.

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Physics, Astronomy & Cosmology / Re: Could a wall constructed of piezo materials such as barium titanate, or PVDF?

« on: 10/05/2015 06:00:36 »

What about silica sand?

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Physics, Astronomy & Cosmology / Re: What type of technology can deflect or block high powered acoustics?

« on: 10/05/2015 04:36:29 »

What about piezo materials?

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Physics, Astronomy & Cosmology / Re: What type of technology can deflect or block high powered acoustics?

« on: 10/05/2015 04:35:53 »

Yes that works but headphones don't cover the entire head and wearing headphones on the head all day with sound running isn't practical.