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Comment Really? (Score 3, Insightful) 367

A post on Slashdot related to the fact that many people lack basic education and/or skills to basic reasoning skills?
And over the top linking/citing a buzzfeed post? Are they now directly feeding their facebook wall on /. now?

I wonder what's worse: A few people believing a film is based on a true story when it obviously can't or the fact that this is posted here. I will ponder on that.

Comment Re:Jail broken devices? (Score 4, Insightful) 217

Anyone who jail breaks is aware of the risk they are taking.

I think they just heard me laugh all the way to China. Seriously, most people can't even grasp the concept of risk when think of software and operating systems. How in the world do you expect them to understand those risk?

No. Contrary to some believes, most (as in almost) all jailbrokers have no clue what they do and have no idea of what are the risks involved and how important (or not) they are.

Comment Re: Summary is inaccurate (Score 1) 118

Yes, you are. The you are right to say that the origin of the name comes from a method to produce light with those specific characteristic. But very few to non device still use this method today.

Gas cavity laser, laser diodes, chemical laser, etc. all do not pass in your restricted vision of what a laser ist. But long has been established to call laser a device that creates light with coherent characteristics as did the first early LASERs.

In your world, it would be wrong to call a car a car because there are nor horses in front of it.

And, by the side, the word laser is now in the oxford dictionnary. Not only it has a definition, but also its not (only) an accronym anymore, so uppercase is not called for in general use. Which leads back to your point: someone talking of a laser diode is correct; not someone talking about a LASER diode.

Comment Re:Don't affect me (Score 1) 317

Somehow, I do not believe you...
Obviously it seems so important to you and affecting you to the point where you feel the need to post a comment in which you are compelled to state that you are running Debian. Why?

Its as if you either feel threatened or superior... in any case it DOES affect you.

Comment Re: Blocked (Score 5, Informative) 132

For those bot getting the "joke", GEMA is pretty much the German equivallent of the RIAA in the US.

They are notorious for geoblocking in Germany videos from youtube which contains content under their licensing rights... Even youtube channels from the artists themselves.

The infamous message "this content is blocked because it contains material owned by GEMA" is a nightmare for youtube users in Germany

And this is where this joke becomes insightful. Once you open the markets in the EU and ban geoblocking, how do you deal with this type of geoblocking? Will they address geoblocking only in a commercial transaction (what would actually be much worse for GEMA in the business model they drive) or address geoblocking in all its forms?

Comment Re:Interesting; likely more limited than advertise (Score 1) 82

Vibrational spectroscopy is non-destructive. You simply observe the vibrational (or translation, or rotation) modes of molecules. Most systems measure what is absorbed (ie. you have an known IR source and measure what of it doesn't get through - assuming the absorbed photons corresponds to vibration modes of the molecule). Although this is an active measurement approach, the energy needs are too long to cause damage to the molecule or samples. But you could go in at higher energy level... this is basically what a microwave oven does, exiting the rotational modes of water molecules. It also work to some extent with reflection, but it will be dependent upon the nature of the sample.

But a vibrating molecule will also emit radiation at wavelength corresponding to the energy of the vibration modes. This enables passive measurement which is not only non-destructive, but also allows measurement without any kind of interaction. Emission IR spectroscopy is used a lot for remote sensing of the atmosphere for example.

So either you are totally passive or only sending a week IR signal which partly gets absorbed and partly transmitted/reflected. A typical IR source for laboratory instruments is a glowbar. That simply a small wire heated to about 800C... it looks a lot like a car cigarette lighter. You won't rip of electrons of your samples with that ;)

Comment Re:Interesting; likely more limited than advertise (Score 2) 82

Thanks for your insights. Still trying to decide whether something like this should go on my wish list ;) (see above for my potential uses).

Don't expect to much of it for the first generation / first product. Once you get a few competitors and iterations on the technology, you can have a serious look at it. I'd also wait to see a view "in-depth technical reviews" with labor-based comparison studies. To satisfy your curiosity, if your budget allows it, it will definitely be worth it (assuming it at least work a little). I expect the results at first to feel a little like translating something in some language with google translate and translating it back with bing.

How accurate, exactly, do you think such a device could be? Obviously it's not going to be pulling out the sort of precision of a professional spectrometer. But you mention, for example, being able to identify the signatures of herbicides and pesticides. Do you mean, for example, "This contains imidacloprid", or more like, "This contains a nicotinoid of some variety"?

It's hard to say without having more detailed information on the spectral range, spectral resolution, illumination source, detector type and sensitivity, and, most importantly, the type of spectrometer. From the description, it seems that it is a diffracting spectrometer, but that again comes in different flavours. Long story short, I can only guestimate the performance of it based on my experience designing such devices with the information they provide. Now, some molecular basis have specific signatures even a low resolution device could identify. Because these molecular basis are shared by various different molecules, it may be difficult to do more as to identify a group such as nicotinoids. And for the same reason you will have a lot of false positives.

This is where the apriori information play an important role. If you are looking at an apple, the spectral database-based/cloud-based analysis program knows what to expect and can raise a warning flag if it sees something which might be a nicotinoid, because that's not expected in the spectra of a "clean" apple. The same analysis program will ignore the warning if you say you are analysing a cigarette. This, btw. may also lead to false negative... but with low spectral resolution, I believe that the cloud-based analysis will play a crucial role. And this is actually the most interesting part of this innovation.

How useful do you think it could be on identifying mineral species - say, distinguishing between different zeolites?

I've never saw an IR spectrometer used for mineralogy or metallurgy. I doubt it can provide you with any significant information in those fields. Other factors you cannot see in vibrational spectroscopy play a too large role.

Or, back to food, if given, say, a mango, to get readings of, say, water, sugar (in general, or specific sugars), fat (in general, or specific categories of fats, or specific fats), protein (in general, or specific categories of proteins, or specific common protiens... obviously it's not going to be able to pull out 5 ppb of Some-Complex-Unique-Protein), common vitamins (generally found in dozens of ppm quantity - some more, some less), minerals (likewise), etc?

This is where I believe the advertisement is way to promising and optimistic. I'd occupy your day to do that on a very expensive and high-performance laboratory IR spectrometer. Under laboratory conditions.

Take this example of sugar spectra from the Agilent website. They don't specify it, but that's most likely 4 cm^-1 resolution. You see that it is possible to identify specific sugar compounds, but also that the spectra are quite alike. Now reduce the spectral resolution to something like 128 cm^-1 and you'll have a hard time identifying the exact type of sugar.

Comment Re:Interesting; likely more limited than advertise (Score 1) 82

There's a reason IR spectroscopy has fallen by the wayside in chemistry - it doesn't give you enough information, and just hasn't kept up with other techniques. It's used for specific tasks, such as monitoring a reaction, but it's not a go-to analysis technique any more.

I couldn't disagree more (although one would say I'm somewhat biased on the applications of IR spectroscopy). First I know no research or production analytic lab without at least one IR spectrometer. In quality insurance they are also used a lot. For in-situ monitoring of reaction, IR spectrometer are generally not appropriate because to slow at sufficient spectral resolution. You can only monitor very slow reactions.

Maybe you are thinking of a specific branch, where other techniques are more appropriate or practical?

And I am surprised by the statement that vibrational spectroscopy doesn't give you enough information. Maybe not enough for a specific task such as identifying elementary elements, but you get a lot of information on the molecular structure of a compound. With gasses you can also do very precise quantitative analysis. I think only NMR spectroscopy will give your more information on the molecular structure and an NMR certainly does not fit in the palm of the hand.

Comment Re:Interesting; likely more limited than advertise (Score 4, Informative) 82

You will not be able to determine raw elements with a NIR spectrometer. With a NIR-LWIR spectrometer, you can only identify molecular compounds, because what you are observing is actually the vibration modes of the molecules. In this spectral range, you will have a lot of signature for organic compounds. So you may be able determine if something is made of plastic. Determining the kind is trickier because most plastics are actually very similar and would require a device with higher spectral resolution to make such a determination.

For elementary elements (iron, copper, gold, etc.), you can forget it. That device will not help you.

Comment Interesting; likely more limited than advertised (Score 5, Informative) 82

Designing spectrometer is what I do for a living and with my experience and knowledge, I have serious doubts this device has sufficient resolving power to do what they claim it can/would/should do. To identify chemical components, you need a minimum spectral resolution (depending on the species you want to identify). To do quantitative analysis, the requirements are event higher. Typically, for solid NIR spectroscopy, I would aim at 2 to 4 cm^-1 spectral resolution. Under this, you can maybe check for the presence of a specific compound or compound family, but the capability to do so will be very dependent on the overall chemical composition.

Its possible to reduce the size of a spectrometer while somewhat keeping the resolution. But that goes only up to a certain extent... and that goes only with trade on signal to noise ratio. At some point physics overtakes wishful thinking. Reducing the instrument, and thus the optical throughput, you need longer measurement times to achieve adequate signal quality. Quantitative analysis with a (large) lab NIR spectrometer can take minutes, depending on the material being analysed. When you design spectrometers, you are constantly trading on aspect for another and by bringing a NIR spectrometer to that size, you traded a LOT of stuff away.

I also see spectral calibration being an issue with this device, then it works in reflectance and not in transmittance. It cannot be self-calibrating and directly provide a transmission/absorption spectrum. Maybe it is calibrated once during the production and assumed to be stable? If that is sufficient is, from my experience, questionable.

On the other hand, this is a very exiting breakthrough. I might even get my hands on one for fun. Why? because its, as they so well market it, a liberalisation of matter. Its a first step in being able to identify any substance that we get our hands on. While it may not yet be able to provide a full chemical make-up of a product, with enough a priori information it may be very useful.

Let me give you an example where such a device can be its money worth. When you buy fruits and vegetables that are bio/organic, you want them really to be that way. This decision to spend more money on these healthier food items is solely based on trust, which is often exploited. I doubt that the analysis of such a product can do what they claim (most of the return information is most likely deduced from the a priori information provided). But even with a limited spectral resolution and sensitivity, it should be able to identify spectral signatures of typical herbicides and pesticides.

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