Gold Nanoparticle - Sixty Symbols

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  • Опубликовано: 21 окт 2024

Комментарии • 389

  • @rioross
    @rioross 12 лет назад +2

    I've only had those chocolate candies on his desk once in my life. They don't sell them here in Minnesota, or anywhere in the US, but I can tell you, they are absolutely fantastic.

  • @Diamonddavej
    @Diamonddavej 13 лет назад +3

    Notice that colloidal gold is red?
    The ancient Egyptians were the first to make used gold nanopartices to color glass red (Ruby Glass) and in the 4th century, the Roman artisans used gold particles 6 nanometers wide to color the glass of Lycurgus Cup red.
    In 1908, Gustav Mie explained how colloidal Gold produce Ruby Glass, Mie Theory, localized surface plasmon oscillations on the surface of metal nanoparticles.

  • @ObjectManipulator
    @ObjectManipulator 12 лет назад +3

    The first one was "A cow to a physicist is basically just a large sphere, sometimes you consider the tail, sometimes you don't." And his analogy for the size of one quintillion was "You'd require a 20 meter deep pile of Maltesers, which spread out over an area the size of Ireland" Hope that helps! :D

  • @RavenMad101
    @RavenMad101 11 лет назад +2

    So Cool, You can really see the structure of the Nanoparticle and a very gridlike structure when you look close.

  • @frederf3227
    @frederf3227 9 лет назад +3

    I remember a professor once rattling off a calculation of "2 times pi, that's ten. Ten times fifteen that's 100, etc." All the operations were that sloppy and in the end the answer had something like 15 zeroes and the sloppy version was only 20% off the careful one.

  • @publiusdg
    @publiusdg 12 лет назад +2

    I hope I'll be as excited as this guy in my future job. He makes his job look so fun.

  • @habichturs4427
    @habichturs4427 11 лет назад +2

    You see a detail of a metal mesh (usually Cu) purpose-made to hold thin foils or layers for TEM investigations. It is covered with a thin film of amorphopus carbon (a "holey carbon film"). The only thing you have to do is, get the gold particles nicely dispersed in their suspension (use an ultra-sound bath), and then let a droplet of that suspension dry on the TEM grid with the carbon film. Then put it into the TEM specimen holder, put that into the TEM, and you're ready to image .

  • @habichturs4427
    @habichturs4427 11 лет назад +2

    One correction: In a typical TEM, the wavelength of the transmeitted electrons is not of the order of magnitude of the interatomic distances (or the distances of the lattice planes), but about two orders smaller. While phycisists are not always very exact, a ratio of just one order is usually described as much smaller, let alone two orders.

  • @habichturs4427
    @habichturs4427 11 лет назад +1

    Yep, that estimate is about right. The TEM image is in simple terms a projected view of the crystal (not like your optical vision of some macroscopic object), so unless the columns of atoms are not aligned to the direction in which the electrons travel you can't see them separated. At 00:10 you see in one part of the crystal a stripe pattern which means that the electrons travelled parallel to planes of atoms (to be exact: parallel to planes far enough apart to be resolved by the microscope).

  • @lasseankerfrederiksen2285
    @lasseankerfrederiksen2285 8 лет назад +13

    I love to see this guy. he really gets so existed when he explains

  • @brianwilson9501
    @brianwilson9501 6 лет назад +4

    His energy is awesome. He would be a great teacher. Wish my teachers had half the energy he has.

  • @Derundurel
    @Derundurel 10 лет назад +2

    I completely agree about people being uncomfortable with inexact quantities. Engineering is full of this sort of thing too - everything has a level of uncertainty attached. Sometimes an order of magnitude answer is sufficient.

  • @tonyhart97
    @tonyhart97 6 лет назад +3

    I first watch this video when I was about 16 and was fascinated and now I'm doing my degree in nanotechnology and only a few weeks ago we made both Au and Ag NPS, it's cool to rewatch this video and see how far both I and the field have come in seven years

  • @yellowmetalcyborg
    @yellowmetalcyborg 13 лет назад +3

    The awesome thing about looking at gold nanoparticles is that you don't have to plate them in gold in order to see them in an electron microscope.

  • @brandonX360
    @brandonX360 13 лет назад +2

    Sixty Symbols is always good fun to watch!

  • @TrueEmergence
    @TrueEmergence 13 лет назад +2

    Oh my god. This channel is one of my favorites thusfar. Thank you so much for the posts.

  • @rushianokun
    @rushianokun 13 лет назад +1

    I LOVE this guy, please feature him again!

  • @w00td00t
    @w00td00t 13 лет назад +1

    Awesome name, awesome taste in music, awesome profession. What isn't awesome about this guy?

  • @1646Alex
    @1646Alex 11 лет назад +2

    yeah, i know. but, i've really wanted to get into theoretical physics for like my whole life, but i've always sticked to more piratical carers, but this video has motivated me to become one.

  • @luis5d6b
    @luis5d6b 11 лет назад +1

    Honestly I would love to get a physic class with this guy or any of the guys from sixty simbols I really love to see when someone gives a class and really enjoys what he or she is teaching as much as I love learnig and it good with getting a lot of questions and intelectual debate about the subjects and this guys seems great, love this videos

  • @zantrua
    @zantrua 12 лет назад +2

    I love how he holds up the paper for pretty much the whole interview. He's so excited haha

  • @IRuinEvrything
    @IRuinEvrything 12 лет назад

    i don't know if there's a tech term for it, but I refer to it as proportional rounding. you have to round everything at its own scale. I imagine you can't really do it until you have a significant amount of intuition with the numeric behavior of a given quantity/quality. some things you round down, others you round up to bal out the behavior of the thing that was rounded down.

  • @Maverician
    @Maverician 8 лет назад +9

    5:33 is amazing to keep clicking back to...
    Sorry Prof Moriarty.

  • @bwub1
    @bwub1 12 лет назад +1

    Actually theyre already being used for some data sorage devices. Not in solution but attached to surfaces. There are loads of cool things you can do with nanoparticles. There are plenty of ways of making them too. Most of the chemistry is fairly simple so you can make them in a lab in an afternoon. Observing them is tricky becuse they're so small, but again there is about a dozen good techniques you can use to get an aproximation of their size and shape.

  • @vevenaneathna
    @vevenaneathna 12 лет назад +1

    maybe nano particles could be a viable medium for recording data due to the refraction of electrons.
    If only we were better at making them and had a way of easily observing them

  • @tomrich553
    @tomrich553 13 лет назад +1

    i made these at my high school as well! it was incredibly fun, and because of it i plan to study nanotech at Leeds next year!

  • @BobStinkfulla
    @BobStinkfulla 13 лет назад

    @AVJRoutledge Electron Microscopes such as the one used to capture the pictures for this study are still being refined, but are approaching the limit of their resolution. This arises from the nature of the electron source used and from the inaccuracies in producing the electromagnetic lenses required to operate the instrument. Other types of microscopes, such as Atomic Force Microscopes of Scanning Tunnelling Microscopes are also capable of achieving atomic resolution and are being improved.

  • @michaelguckian5373
    @michaelguckian5373 8 лет назад +4

    Have you / can you run some high speed camera imagining at the the nano scale. Maybe we can see movement of patricles image how quick things are moving at this scale.

  • @Waltham1892
    @Waltham1892 13 лет назад +1

    If only every student could have a teacher like this...

  • @24938839
    @24938839 8 лет назад +140

    I like the fact that he thinks americans know the size of Indiana

    • @fudgelame
      @fudgelame 7 лет назад +1

      Ireland probs understandable than Indiana.

    • @VeggyZ
      @VeggyZ 6 лет назад +1

      I think (hope) everyone watching this video knows at the very least that Indiana is roughly the same size as Ireland.
      Quite the mind-trip. But it's just an approximation.

    • @randellporter8747
      @randellporter8747 6 лет назад

      Lactose69: Your a pompous idiot. I'm guessing a13 year old pompous idiot.

    • @-yeme-
      @-yeme- 6 лет назад +1

      VeggyZ I had no idea how big Indiana was, or where it was until I looked just now. I knew it was a state and I was sure it wasnt one of the huge ones in the west but that was all. I wonder how many Americans would know how big the county of Devon, where I live, is, or be able to point it out on a map. A minority, I would imagine, and probably a small one.

    • @666wurm
      @666wurm 6 лет назад +2

      Indian 94.321 km², Ireland 84.421 km² - that is 11.7% off! Ridiculous!

  • @vanessacherche6393
    @vanessacherche6393 9 лет назад +10

    Excellent choice for random cd on bookshelf!

  • @gulllars
    @gulllars 13 лет назад

    @Robaaaayy it's like the quote from the theme song of flashdance, "Take your passion and make it happen".
    I was almost through the second year of chemistry in university when it hit me although i was skilled at it, i didn't have a passion for it, and my passion for computers, which had always been a hobby, had grown to the point i decided to do just that, make it happen. It feels like comming home without ever knowing you weren't there already, but at the same time deciding to do so is scary.

  • @AVJRoutledge
    @AVJRoutledge 13 лет назад +1

    I’m very addicted to all these. One question for anyone who knows the answer!!
    How much more powerful are these microscopes going to get?
    Have they reached a critical limit?
    Are there new ones coming out?
    Will they continue to be refined?
    Are we going to get even more detail?

  • @DoctorFastest
    @DoctorFastest 12 лет назад +1

    @MrChemify My understanding is they use electrons because of the short wavelength. The problem with using DLS on something like this would be scattering off of multiple particles within a single wavelength, complicating the interpretation of the scattering significantly. I'm not an expert, but I'd be surprised if DLS worked on these scales. I know that it's useful for larger stuff, like proteins, polymers, etc.

  • @richardfrieman
    @richardfrieman 7 лет назад +2

    I know I'm like 7 years late, but the statement about crystal faces was flawed. Although it's true that Diamonds have crystalline structure, we never see it grow out. Raw diamonds are rough because they grow within a matrix of ultrabasic magma that formed within Earth's mantle. They then get eroded out at the surface where they are subsequently found often on beaches of oceans and rivers. The facets that we see on diamonds are cut and polished by humans. Quartz would have been a better analog; when quartz is allowed to grow in a void, it forms beautiful obelisk shapes with naturally occurring crystal faces like those on the gold nanoparticle.

  • @codykonior
    @codykonior 13 лет назад +2

    I'd have liked some extra explanation on why nanoparticles are important. Perhaps a future episode? :-)

  • @habichturs4427
    @habichturs4427 11 лет назад +1

    Forget about your imagination of "size of an atom". All what matters here is the electric potential which deflects the electrons, in other words, affects the phase of the wave of the fast transmitted electrons. Gold atoms have a high Z (large charge in the nucleus) meaning they have a high scattering cross-section. You could detect an individual Au atom with a good TEM (better with a STEM). However, it is energetically so favourable for the atoms to stick together that none would separate).

    • @bbbilge
      @bbbilge 6 лет назад

      Doğada ALTIN zaten en çok sularımızda iyonize halde bulunmakta tüm canlıların metobolizmalarına dahil olmaktadır. Paradan farklı olarak altın iyonize olarak yenilebilir ve etkileri gerçeküstü gerçeklik ötesidir. DMT ruh ya da tanrı molekülü sentezlenmesinde metabolik olarak işlevseldir.
      İki Türk bilim insanı suda iyonize halde bulunan altın atomlarını virüsleri genetik olarak yeniden modifiye ederek toplamayı başarmışlardır. Bu süreç başta akıllı yaşam türleri olmak üzere dünya üzerindeki canlı yaşam türleri ve beyin sinir aktivasyonları için uzun vadede geri dönülemez etkilere neden olabilir.

  • @experthe9574
    @experthe9574 13 лет назад

    This is such a coincidence, because just a few days ago I made gold nano particles for a class as well.

  • @arothn89
    @arothn89 12 лет назад +1

    queens of the stone age, this guy just keeps getting cooler!!

  • @ramonbril
    @ramonbril 13 лет назад

    @calmo15
    It is not the diffraction that stores information, it is just that the difference between two lines of holes in the cd is about the wavelength of light. Though you can store information on nano particles if you hold the capability to write and read on that level.

  • @RM_RM_RM
    @RM_RM_RM Год назад

    Very beautiful 5-fold twin of gold

  • @adeel256
    @adeel256 11 лет назад +1

    love the little diversion. that's what makes it human. beautiful!

  • @JustinRiedyk
    @JustinRiedyk 12 лет назад +1

    It's mind blowing that the tiny particle is still 120,000 atoms.

  • @Dracanic
    @Dracanic 13 лет назад +1

    I absolutely love this series. My goal is to get a physics degree and this channel is keeping that dream alive

  • @criddell86
    @criddell86 13 лет назад +2

    Possibilities of electrons being used to read/write to the surface of nano particles to store data in large volumes?

  • @RockMedved
    @RockMedved 13 лет назад +1

    This is my favorite sixtysymbols guy.
    BTW I rather enjoyed the envelope part, since about 90% of my Maths calculations are all across my bills and envelopes too :D

  • @Jumiconnard
    @Jumiconnard 12 лет назад +1

    It looks like it has a 5-fold simmetry, just like quasicrystals :o

  • @singlespies
    @singlespies 13 лет назад +1

    I am most interested in the imaging process and enjoyed the explanation of the "lines" in the image of the nanoparticle. Was wondering if light cannot be used to image things that small and why...

  • @borandiUK
    @borandiUK 10 лет назад +5

    Shame he didn't start talking about the quantum dot effect, and that different sizes of gold nanoparticles produce different colours.

  • @FalcoGer
    @FalcoGer 11 лет назад

    the wavelength of the electrons that were used to make that image...
    i wasn't even suprised to hear that anymore, i even guessed that before you said it

  • @JuanLeTwnz
    @JuanLeTwnz 13 лет назад

    I really didn't expect him to take Rated R out of the cupboard.
    Makes me want to give this vid 1 quintillion thumbs up :)

  • @sniped101
    @sniped101 12 лет назад +1

    If I had one of these guys as a teacher when I was in middle or even highschool, I'd probably be a physics major..

  • @dezerterone
    @dezerterone 9 лет назад +2

    'Restricted' - good choice! :)

  • @Confuseddave
    @Confuseddave 7 лет назад +3

    I thought the SI unit for large size comparisons was Wales.

  • @bigboam
    @bigboam 12 лет назад +1

    My question is: does all of that rounding ultimately create minor errors? i.e. are we (ever so slightly) miscalculating the orbits of planets, etc., by rounding to three or four significant decimal figures?

  • @drakan
    @drakan 12 лет назад +1

    depends upon where within the equation you're rounding, to be honest. You round something at the beginning, it's going to progressively get more and more inaccurate as you scale the value upward

  • @e1doller
    @e1doller 13 лет назад

    @isreasontaboo you can create these using a gold salt and trisodium citrate to reduce it. the lee and misel method is pretty well known.

  • @Goodwithwood69
    @Goodwithwood69 9 лет назад +4

    QOTSA best album by far!

  • @talk74
    @talk74 13 лет назад

    A great way to start my Saturday morning...cheers!

  • @ifsey
    @ifsey 13 лет назад

    4:12 Some nice product placement there! Malteasers- Food for thought!

  • @WildBillCox13
    @WildBillCox13 10 лет назад +2

    Off topic, but is a neutron liquid (cf Neutron Star) stable enough to parse fractions of it and the parsed neutron components stay within the limits of a common surface tension? Or does any small amount of it (said neutron liquid sample) readily ablate into nothing? The reason I'm asking is that I've been wondering about element drip lines, pursuant to the possibility of artificially (is there any other way?) creating super nuclei in excess of those we've already achieved. Rather than using existing accretional methods of amalgamating heavier nuclei than those we find in nature, perhaps, could we, for sake of argument, begin with a matrix of neutronal moderator and thus overcome Coulomb resistance?

    • @Saki630
      @Saki630 10 лет назад +1

      William Cox I have no idea what you are talking about. At the beginning you propose a thought experiment where you take a piece of a Neutron Star and try to stabilize the neutrons long enough for them to decay into elements? Then You want to have Neutronal Moderators to do what? I thought NM's were just atoms/molecules put in place to capture neutrons and slow them down as they pass through in nuclear reactors. Do you want to use NM's to stabilize this neutron star matter? Also why would you assume pieces of a Neutron Star are liquid?

    • @bbbilge
      @bbbilge 6 лет назад +1

      Ultra heavy materials and welcome black hole?...

    • @robinswamidasan
      @robinswamidasan 5 лет назад

      @@Saki630 Excellent response!

  • @jerommeke69
    @jerommeke69 13 лет назад

    @singlespies
    nope, light cannot be used.
    Look up "angular resolution" on Wikipedia to learn why!

  • @iowanthomas
    @iowanthomas 13 лет назад +3

    This man is truely inspirational, I would pay a very large sum of money to spend time learning with him.

  • @evilferris
    @evilferris 13 лет назад +6

    @ThermalHD
    $52 per g; current gold price in grams
    197 g in a mole
    6.023×10^23 atoms in a mole
    125,000 atoms/particle or 1.25×10^5 atoms
    (1.25×10^5) / (6.023×10^23)= 2.075×10^-19 mole
    (2.075 × 10^(-19) × 197g = 4.088 × 10^(-17)g
    4.088 × 10^(-17) × $52 = $2.13 × 10^(-15) or
    $.00000000000000213
    Somebody check my math?

    • @zeryphex
      @zeryphex 6 лет назад

      @evilferris
      I'm sure your math is ok ... but there could be billions of dollars made from collecting gold particles in all the world's oceans ... and plenty of gold from recovery in electronics waste.

    • @teyton90
      @teyton90 6 лет назад

      i'm sure it's ok, since you had 7 years to figure it out

  • @djangogeek
    @djangogeek 8 лет назад +1

    +Philip Moriarty
    So are the diffraction patterns from the electrons scattering constructive interference?

    • @robinswamidasan
      @robinswamidasan 5 лет назад

      Alternating constructive and destructive interference.

  • @NordicLab
    @NordicLab 12 лет назад

    which were obtained by these particles? Are there studies using dynamic light scattering?

  • @pro4skill
    @pro4skill 12 лет назад

    The uncertainty principle says that we can't know a wave-like particle's velocity if we know its position, and vice versa. This principle does not apply to calculating the volume/diameter of something.
    Seeing atoms also does not deal with the uncertainty principle; they are not wave-like, though they consist of wave-like particles. Not seeing the individual atoms is due to the fact that they are so incredibly small, and the zoom of that particular picture was too big to capture individual atoms.

  • @DrScully25
    @DrScully25 10 лет назад +1

    I got so wound up and excited watching this haha

  • @1vrsc
    @1vrsc 11 лет назад +1

    awesome stuff! American Idol zombies don't know what they are missing...should be watching things such as this. This is where real talent is...science

  • @cristianfcao
    @cristianfcao 13 лет назад +1

    Some weeks ago I've learned how many atoms are in a grain of salt.
    Are you ready?
    About 1.2 *10 ^ 18, or: 1,200,000,000,000,000,000 atoms!!
    That fact alone multiplied my admiration for particle physicists by at least a billion. :-)
    I mean how is it possible to study something so unimaginable small? That there are protons, neutrons and electrons, which are so much smaller than the atom itself, and then quarks within the protons and neutrons that are smaller still!!

  • @PacRimJim
    @PacRimJim 10 лет назад

    It's not necessary to compute exactly, but it is essential to know how to compute exactly.

  • @ItsNickFox
    @ItsNickFox 11 лет назад

    What you typed would only tell you how many atoms wide the nanoparticle is. Instead, you need to find the VOLUME of the particle and the atom and divide the former by the latter. Assume both are perfect spheres for simplicity's sake and you'll get the proper answer.

  • @youarebeyondthought
    @youarebeyondthought 13 лет назад +1

    God I love these videos. Thank you so much!

  • @NordicLab
    @NordicLab 12 лет назад

    @DoctorFastest I use a laser at 720 nm wavelength for DLS. According to his passport instrument measures the size of 0.8 nm. But if he could see the separate particles, I do not know. At least I got it a size of 3-5 nm with mixed peaks.

  • @MindLessWiz
    @MindLessWiz 13 лет назад

    Awesome! I didn't realize that about CD's. That's good to know.

  • @belliebum12
    @belliebum12 12 лет назад

    Living in the U.S., I appreciate the comparison change to one of the states. The problem is, I have little idea as to how big Indiana is... I should know this but I don't. Indiana's just one of those states that doesn't have anything that distinguishes it from the other states. Apologies to those living in Indiana.

  • @Musicguy208
    @Musicguy208 13 лет назад +1

    Always awesome! I love these videos!

  • @FunnyHacks
    @FunnyHacks 13 лет назад

    A fantastic talk!

  • @balasubrahmaniyamM
    @balasubrahmaniyamM 4 года назад

    Regarding the lines in the image, are they really diffraction orders? The diffraction orders happen on the Fourier plane am I right? This is image plane right, so the distance between those lines must be the actual distance between those atoms am I right?

  • @krazedgunner
    @krazedgunner 12 лет назад +1

    I love videos like this, im getting interesting just learning about it. can I ask you about that electron microscope? is it over $15 grand :)

  • @Agemrepus
    @Agemrepus 13 лет назад +1

    I just always wonder this (yes, I AM a first year haha), but if you were to take everything to the 19th decimal (or more), wouldn't that make all of your calculations even more accurate? And wouldn't that in tern aid in better conclusions?

  • @120Luis
    @120Luis 5 лет назад

    Nice, that was Rated R, the best one of their albums

  • @BruceNJeffAreMyFlies
    @BruceNJeffAreMyFlies 12 лет назад

    Yeeeeesss!!! Moriarty listens to Queens of the Stone Age.
    What a legendary physicist!

  • @calmo15
    @calmo15 13 лет назад

    @Brillyr thats what im saying, could you use the diffraction patterns to read the information?

  • @isreasontaboo
    @isreasontaboo 13 лет назад

    How are these created? Using some sort of chemical vapour deposition techniques?

  • @beeble2003
    @beeble2003 11 лет назад

    There are errors but they're from imprecise measurement, not rounding. For example, Usain Bolt ran 100m in 9.58s. It doesn't make sense to give his speed as 37.578 km/h because the real distance might have been 99.98m (rounded to 100m) and the real time 9.576s (rounded to 9.58s), which is 37.586 km/h. For this reason, you only quote calculated values to a degree of precision equivalent to the precision of the original measurements. (In this case, the time is only accurate to one part in 1000.)

  • @rmenchoachupicachu
    @rmenchoachupicachu 11 лет назад

    from what I understand, these nanoparticles are clumps of gold atoms that are mixed with another element to form these particles which are in the solution. The structure is confuses me though.

  • @exodiatheforbiddenone8228
    @exodiatheforbiddenone8228 5 лет назад

    Do you know how much gold nanoparticles cost for athletes who are injured?

  • @habichturs4427
    @habichturs4427 11 лет назад

    If a phycisist determines a value, she or he needs also to determine the (order of) the error of that determination. The rounding is then just down to omit all digits which are smaller than the error so to not carry on fake data. And: there are certain rules to round up or down, that's nothing to do with intuition ...

  • @beeble2003
    @beeble2003 11 лет назад

    I was talking about average speed, not top speed. My point was about errors in measurement: it doesn't make sense to quote the average speed to five significant figures when you've only measured things to three.

  • @frysebox1
    @frysebox1 12 лет назад

    @PappaKnowsBest
    I'm pretty sure if I just solved for the symbol representing the value and unit of what you're looking for in a question through algebra, and didn't bother to put in any of the values given for any of the questions, I'd still get an okay grade on my physics exam.
    We've always been told in maths and physics that how you get there is the important part.
    Also if you answer with a number but don't account for valid decimals but just write what your calculator says, you lose points.

  • @calmo15
    @calmo15 13 лет назад

    if the nanoparticle diffracts electrons in the same way that CDs diffract light, would it be possible to store information on the and make like a nano hard drive?

  • @subach
    @subach 13 лет назад

    I do the same thing when I need to do a side calculation I just grab the nearest thing I can write on. No envelopes, but I've written equations on a few Chinese food menus.

  • @willwoodhouse
    @willwoodhouse 13 лет назад

    @Agemrepus yeah it would but a lot of measuring equipment isn't actually accurate enough to measure that precisely, so its usually best to stick to relatively few D.P.s

  • @Drag0nfoxx
    @Drag0nfoxx 13 лет назад

    @Ormaaj as far as I know single atoms can only be seen directly via a scanning tunneling microscope (something like that, i'm not completely sure about the name).

  • @guerra_dos_bichos
    @guerra_dos_bichos 9 лет назад

    What is the value o pi? about 4...

  • @m.c.4674
    @m.c.4674 3 года назад

    Why can't I see the atoms of the ground the crystal is on .
    I would like a detailed explanation how your instruments work

  • @frankcowan6625
    @frankcowan6625 7 лет назад +1

    Qotsa
    I didn't tink I could love you any more.....
    My man!

  • @mathie92
    @mathie92 13 лет назад

    that was the first thing i learned at university make guesses and approximations that was our first lesson physics

  • @FrostPegasus
    @FrostPegasus 13 лет назад

    How come the electrons from an electron microscope don't react with the atoms you're trying to view?