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Hydrogen weakly dissolves into pure iron (including iron below 1185 K, therefore solid in alpha phase). The solubility increases with temperature. Same with other metals. I've been trying to find out what effect the dissolved hydrogen has on electrical resistivity. I can find journal articles on the effect of hydrogen forced out between crystal boundaries by fast cooling (super-saturation), but that's not what I am after. Can anyone help on this? Assuming dissolved hydrogen affects resistivity, which it surely must do, by increasing the probability of drift electrons encountering atom interference, is the effect different above and below the Curie point (1043 K)? 139.168.241.56 ( talk) 02:28, 23 May 2014 (UTC)
http://dhmo.org/facts.html lists "Dihydrogen Oxide, Hydrogen Hydroxide, Hydronium Hydroxide, or simply Hydric acid" as alternate names for this horribly destructive compound. Are all of them valid names by IUPAC nomenclature? All four of them are redirects, with three different targets:
In particular, I'm left wondering whether "hydric acid" is perhaps an invalid name. I'm tempted to send all of them to WP:RFD, saying that all should go to the same place, and asking people to decide which place. If that's a chemically bad idea, please let me know so I don't waste people's time at RFD. Nyttend ( talk) 03:29, 23 May 2014 (UTC)
Relative to heavy water, ordinary water is acidic. Count Iblis ( talk) 11:48, 23 May 2014 (UTC)
Yesterday I took some pictures of thunderclouds near the horizon which contained very nice deep red colors near the horizon. But whatever I tried with reasonable white balance settings, the colors in the picture were far off from containing that very deep red color. It looks like faint orange. Of course, I can correct that with digital processing of the pictures, but I'm not sure why a reasonable white balance setting wouldn't have led to a result that is at least approximately correct. Or could this have to do with me being red-green color blind? Count Iblis ( talk) 12:00, 23 May 2014 (UTC)
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I'll see if I can upload the image. I did also take HDR pictures with my Sony SLT-A58. There are two options for this, I think in one it applies a different gamma correction (the raw pictures are 16 bit, so there is plenty of room to increase the dynamic range). In another setting (only available when you are not shooting in RAW), the camera takes 3 pictures and combines them automatically to a HDR picture. But I did not see the deep red in the HDR pictures. Count Iblis ( talk) 13:05, 25 May 2014 (UTC)
Color modeling theory (in particular photographic rendition of colour) is quite a complicated subject. See for example RGB color model and links found therein. One would indeed love a device that perfectly rendered image color as the typical human discerns the object. First there is the issue of "typical": as others have mentioned above color blindness is an extreme example of the variance in human color perception. There are even arguments (I believe) about the correct modeling for human color perception. More mundanely your camera (I suppose it to be digital) is almost certainly using an array of three different color filters in front of the photo-cathode which itself has a wavelength response. Careful design can emulate in the product a "good" rendition of the color in the image that you would have seen in the object (though that will depend also on the image display medium/technology). Here is another extreme example. Your cell phone camera provides decent color rendition under most conditions. But use it to look at the front of your TV remote as you click it. You will see the (near) infrared diode blinking--not a color since we don't see it at all, just due to your cell phone's camera sensitivity to wavelengths of light at which us mere mortals are insensitive to. Juan Riley ( talk) 22:01, 26 May 2014 (UTC)
Science desk | ||
---|---|---|
< May 22 | << Apr | May | Jun >> | May 24 > |
Welcome to the Wikipedia Science Reference Desk Archives |
---|
The page you are currently viewing is an archive page. While you can leave answers for any questions shown below, please ask new questions on one of the current reference desk pages. |
Hydrogen weakly dissolves into pure iron (including iron below 1185 K, therefore solid in alpha phase). The solubility increases with temperature. Same with other metals. I've been trying to find out what effect the dissolved hydrogen has on electrical resistivity. I can find journal articles on the effect of hydrogen forced out between crystal boundaries by fast cooling (super-saturation), but that's not what I am after. Can anyone help on this? Assuming dissolved hydrogen affects resistivity, which it surely must do, by increasing the probability of drift electrons encountering atom interference, is the effect different above and below the Curie point (1043 K)? 139.168.241.56 ( talk) 02:28, 23 May 2014 (UTC)
http://dhmo.org/facts.html lists "Dihydrogen Oxide, Hydrogen Hydroxide, Hydronium Hydroxide, or simply Hydric acid" as alternate names for this horribly destructive compound. Are all of them valid names by IUPAC nomenclature? All four of them are redirects, with three different targets:
In particular, I'm left wondering whether "hydric acid" is perhaps an invalid name. I'm tempted to send all of them to WP:RFD, saying that all should go to the same place, and asking people to decide which place. If that's a chemically bad idea, please let me know so I don't waste people's time at RFD. Nyttend ( talk) 03:29, 23 May 2014 (UTC)
Relative to heavy water, ordinary water is acidic. Count Iblis ( talk) 11:48, 23 May 2014 (UTC)
Yesterday I took some pictures of thunderclouds near the horizon which contained very nice deep red colors near the horizon. But whatever I tried with reasonable white balance settings, the colors in the picture were far off from containing that very deep red color. It looks like faint orange. Of course, I can correct that with digital processing of the pictures, but I'm not sure why a reasonable white balance setting wouldn't have led to a result that is at least approximately correct. Or could this have to do with me being red-green color blind? Count Iblis ( talk) 12:00, 23 May 2014 (UTC)
.
I'll see if I can upload the image. I did also take HDR pictures with my Sony SLT-A58. There are two options for this, I think in one it applies a different gamma correction (the raw pictures are 16 bit, so there is plenty of room to increase the dynamic range). In another setting (only available when you are not shooting in RAW), the camera takes 3 pictures and combines them automatically to a HDR picture. But I did not see the deep red in the HDR pictures. Count Iblis ( talk) 13:05, 25 May 2014 (UTC)
Color modeling theory (in particular photographic rendition of colour) is quite a complicated subject. See for example RGB color model and links found therein. One would indeed love a device that perfectly rendered image color as the typical human discerns the object. First there is the issue of "typical": as others have mentioned above color blindness is an extreme example of the variance in human color perception. There are even arguments (I believe) about the correct modeling for human color perception. More mundanely your camera (I suppose it to be digital) is almost certainly using an array of three different color filters in front of the photo-cathode which itself has a wavelength response. Careful design can emulate in the product a "good" rendition of the color in the image that you would have seen in the object (though that will depend also on the image display medium/technology). Here is another extreme example. Your cell phone camera provides decent color rendition under most conditions. But use it to look at the front of your TV remote as you click it. You will see the (near) infrared diode blinking--not a color since we don't see it at all, just due to your cell phone's camera sensitivity to wavelengths of light at which us mere mortals are insensitive to. Juan Riley ( talk) 22:01, 26 May 2014 (UTC)