According to this glass manufacturer it is more aout the otical roerties than mechanical ones. They are looking for:They use orosilicate glass and aluminosilicate glass, which are y themselves scratch-resistant

• Related Questions

Storing icycle helmetswill temerature affect the erformance of the helmet?Yes the cold will affect the foam! OK it's a slightly facetious answer ut as you say it's a searate garage how secure is it? In the cold weather the local mice \ rodents \ what have you will love the foam and use it for edding material. Make sure it is securely stored otherwise it might get shredded. I seak from exerience!

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Which type of PVC for exposed outdoor use?

You could try the gray colored Schedule 80 PVC pipe. This is a much heavier duty material that will stand up to being outdoors. It is recommended by manufacturers. such as U.S. Plastic Corp, that PVC pipe and fittings be painted after installation with a coat of white water based latex paint to provide for UV resistance. The UV light is what is part of the sunlight that can degrade PVC. Link to manufacturer PVC Pipe Catalog:

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Active noise cancellation effects on hearing

The noise cancellation is in theory "adding" sound, but with almost identically mirrored (completely opposite, so positive vs negative and negative vs positive) soundwaves.By "adding" a negative thing it's effectively reducing the soundwaves before they reach the ear. The result is less noise

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Catalyst for Formic acid decomposition

The wikipedia article of formic acid mention that decomposition of formic acid is carried out in the presence of acid, platinum or ruthenium catalyst.Heat and especially acids cause formic acid to decompose to carbon monoxide (CO) and water (dehydration). Treatment of formic acid with sulfuric acid is a convenient laboratory source of CO.In the presence of platinum, it decomposes with a release of hydrogen and carbon dioxide.$$ceCH2O2  H2  CO2$$Soluble ruthenium catalysts are also effective(...)For laboratory purposes, treating it with sulfuric acid is the best way.

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At what point do I need snow goggles or glacier glasses when hiking?

When I first planned my trek in Himalays I was suggested to keep my Gogs and Glares with me when I am outdoor-bound, in snow.

A good article in my Adventure related Database rtf files says:Hours of bright sunlight can burn the surface of the eye, causing a temporary but painful condition known as Photokeratitis. Over time, unprotected exposure can contribute to Cataracts, as well as cancer of the eyelids and the skin around the eyes.UV exposure also may increase the risk of macular degeneration, the leading cause of blindness in people over age 65. While cataracts can be removed surgically, there is no way to reverse damage to the macula, the area in the center of the retina.

To protect your eyes, it is important to wear sunglasses that block out harmful UV light.A coating of snow reflects nearly 80% of the sun's rays. This means that your eyes are subjected to 80% more light on a clear day when the ground is covered with snow than when you are on a grassland.One more tip for ya fellow: I guess, You know that Retina is that magical thing which makes you see things by simply converting light into electrical signals and send it to brain. To make you see something, most of the light is incident on the center of the Retina. And, the retina is more sensitive to Blue and Yellow light. Thats why I chose to have a Blue tinted Snow Gog. So, one such glass will help your eyes filtering out most of the light that is not blue or yellow and will make it easier to see objects directly ahead.

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Why do older (green) PCBs have primarily a darker color, whereas new ones are lighter

There isn't a tight specification of the color for PCBs.

So it mainly depends on the mask materials the manufacturer actually uses.Even if the PCBs were manufactured in the same location, there is no guarantee that the color would be the same between two batches.The pictures that you shared are not for the same PCB so we can't determine much from there. One picture has filled vias, while the other does not, one has chemical gold while the other doesn't.

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How do I know the lightbulb I am buying is UV-filtered?

If you need to illuminate documents that you are "scanning" in such a manner, and you wish to filter UV light, a sheet of your average picture framing glass between the bulb and the document should filter out most UV light. If you are intent on filtering out as much of it as you can, you could pick up a small piece of multi-coated museum glass, which will transmit more visible light and filter out more UV light. Keep in mind museum glass is far more expensive than standard framing glass.

You will probably also want to cover the glass sheet with some thin paper in order to diffuse the light, as the comment by Gene states. You will definitely want to diffuse the light to better illuminate the subject you are photographing

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Can you temporarily make an infrared digital camera normal again?

Short answer : yes you can.From your update, your NEX is in "full spectrum" mode : the sensor filter has been removed and a glass equivalent has been added to replace it (description of this operation for a NEX 6 available here : As your sensor is natively sensitive to a wide range of frequency, it detects now even the "invisible" radiations.In theory, you can do any kind of photography : UV, IR, including classical photography (i.

e. "regular" spectrum). For the last case, you just have to put a IR\/UV blocking filter in front of the lens. In practise, having to use such a filter has drawbacks.Depending of the UV\/UV filter technology, you can encounter some known issues :The white balance isn't a problem if you are shooting in RAW : some post-processing will take care of it. For JPEG, you will have to change the settings of your camera in function of the EM part you want to get (this isn't really a problem). Finally, taking into account that a good 67mm IR\/UV is about $80 and that an used NEX 3 can probably be found about $150, you might be better off buying another used body

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Do cool white LEDs emit UV light?

Not likely. The doping required to get an LED to emit UV is considerably more expensive than the doping needed for visible light. You can buy a UV LED, but no manufacturers, not even the cheap ones, would include it in an LED product unnecessarily

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Why doesn't light kill me?

I have a somewhat non-physics answer for you. If you allow me to broaden your question a bit to "why doesn't light kill or otherwise make all life on Earth impossible" the answer is that the Earth is in what we call "the habitable zone".If the Sun produced so much light or light at such high energies that it would kill you, it also would heat the planet so much that liquid water would not be possible. In this case, it's probably reasonable to argue via the "anthropic principle" that we live on a planet in the habitable zone because otherwise we wouldn't exist to ask such questions. Note of course too that we've defined the habitable zone based on our own life parameters so there is a bit of a circular definition here

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Code Security of ARM Cortex M4 MCU

Complete is never possible. You can just raise the effort & cost. It has nothing to do with 'cortex m4', but everything with the manufacturer's implementation of the chip. Your chip has the usual set of read\/execute protection bits. I doubt much is known in the (open) literature about the detailed weaknesses of such a new chip.

Very generally speaking, such a 'run-of-the-mill' protection scheme is OK against individual hackers, most countries, and low-budget competitors. It probably won't hold against a large corporate competitor (IBM\/Apple\/Google sized, especially if they own a chip fab), the CIA, or the combined effort of the hacker community.A notable way to protect your code is to hide as little as possible, so reduce the population that will take part in hacking your product. If the 'combined hacker community' wants to do something with your device that you don't really object to, make sure they can do that without totally hacking your device. That will substantially reduce the combined effort put into hacking it. What the mechanisms will be that can be used to circumvent the protection scheme of this particular chip can't be predicted, but you can read how other chips have been cracked for an idea of the range of methods. Just a few:.

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How to measure the wavelengths of ultraviolet lines in the hydrogen spectrum?

It's common to measure spectra in the non-visible region and UV or infra-red spectrometers are available off the shelf. Google for many, many manufacturers of the kit. Also see the Wikipedia articles on UV spectroscopy and infrared spectroscopy.

Typically UV and IR spectrometers will use a diffraction grating to disperse the light and a photomultiplier tube to detect the radiation

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Why is plexiglass not used for car windows?

In Israel people who live in dangerous areas can have their car windows replaced for free. They replace the front windshield with bullet proof glass. The side windows are replaced with some type of plastic to protect from rock throwing. The side windows do scratch and turn a yellowish color after a few years and then they can be replaced

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T5 AgroLED, Hortilux PowerVEG FS UV, UV and Mold

Do you have major fans blowing the air? You can have the best lights but without air movement you will get mold and fungus. Send pictures please of your set up, types of plants, what you have added for fertilizer, type of soil, drainage, how close are your lamps...any little detail will help! Right now go get a fan to move that air and humidity!.

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What could have caused CFL bulbs to glow during a power outage?

This is normal for fluorescent bulbs. You should be able to see the same thing when you turn off the light fixture using a regular switch instead of dropping a tree across your power line.Fluorescent lights generate light by an electrical discharge through the mercury vapor in the tube; the mercury emits UV light, which excites electrons in the phosphorus coating the tube. When those electrons decay, they emit visible light. However, there can be a delay between excitation and decay, so you'll see some light emitted for a while after the bulbs lose power. Variations in construction between manufacturers or even between individual bulbs mean that they'll glow for different amounts of time

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Why do red wines tend to be stored in green bottles and white wines not?

The flavour of Red Wines deteriorates greatly due to the breakdown of the wine in the bottle when exposed to UV light. White wines don't have this problem as much as they are much more filtered and do not contain tannens, etc that break down this way. That's my understanding at least, I read something along these lines in the book "Making Good Wine" (ISBN: 9781405036016).A quick google found a very technical study performed - and I'm sure there's a lot more supporting material than this!

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How to make UV light visible

The lens of the human eye naturally filters out UV light. When the lens is removed, as in some cataract surgeries, some people can see light below the 400 nm range that is the typical limit.Slashdot Article During one of the World Wars, the British feared that German ships might communicate with spies on land by using ultra-violet lights. So they trained Grandmas near the coast who had received cataract surgery to sit on their porches and watch the ocean during the evenings.I don't recommend having your lens removed in order to see UV light. But it may be an option

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Do polarized sunglasses protect against UV?

Polarized sunglasses, as with other type of sunglasses may not block enough UV to be considered safe. From WikiPedia:for adequate protection, experts recommend sunglasses that reflect or filter out 99-100% of UVA and UVB light, with wavelengths up to 400 nm. Sunglasses which meet this requirement are often labeled as "UV400.In other words, you have to check the manufacturer's information on what degree of UV protection the sunglasses afford, polarized or not.