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  @mediwise24742 күн бұрын

  HI SIR sir i have to make master curve for frequency sweep data at every temperature i have loss and storage modulus values vs frequency now i want to make master curve please help

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  @Czarlol8 күн бұрын

  Wanted to bore the holes of my stock gaggia basket because they had tonnes of burrs from the factory grinding process. This data was super helpful! Used a 0.3mm needle and some polishing compound to even out the holes.

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  @stevenabbott36857 күн бұрын

  Glad it was useful!

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  @chun531011 күн бұрын

  Hey professor Steven， would you like to be an adhesive consultant? I am working for an adhesive industry and we are looking for an consultant to collaborate with, please let me know if you are interested in this offer.

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  @stevenabbott368511 күн бұрын

  I do a lot of adhesion consulting across a broad range of adhesion problems. Feel free to contact me via my email (it's on my website) if you'd like to discuss.

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  @chun531011 күн бұрын

  @@stevenabbott3685 Wow！ great 👍, I will reach you soon from your website. Thanks for the reply!

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  @JesstyEissejАй бұрын

  Wow, thank you Professor, your website is such a fantastic resource!

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  @stevenabbott3685Ай бұрын

  Thanks for the kind feedback!

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  @leonardindrayana51623 ай бұрын

  I opened a screen printing shop. Your downloadable pdf help me alot. Thank you so much

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  @stevenabbott36853 ай бұрын

  Thanks for the kind feedback!

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  @BehnamKhorramdel-zl2sr3 ай бұрын

  Is there somewhere that I could download the Autotype Screen Print Animator?

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  @stevenabbott36853 ай бұрын

  Here's a link to the whole zipped package: www.stevenabbott.co.uk/AutotypeDSP.zip. But note two things. First, it's very very old and you may have to "run as administrator" to get it to recognise old-style support files. Second, I offer no support, guarantees, trouble-shooting so you're on your own. Having said that, I use it from time to time on my Win 11 laptop and it's fine. But your mileage might vary. Steven

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  @BehnamKhorramdel-zl2sr3 ай бұрын

  @@stevenabbott3685 Thanks very much!

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  @sss336785 ай бұрын

  Thank you very much for sharing this. I really appreciate it!! I have a question about unit in these equations. for example, it seems like there's no unit for V_H (dispersion force), but there is unit for V_D (coulombic, unit is Joule). I want to apply my system.. but I'm confused with unit. please could you check the unit..? I try to calculate but these unit doesn't match for me between dispersion (no unit) and coulombic forces (J).

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  @PaulHarms-em5dp6 ай бұрын

  Thank you

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  @litchiliu6 ай бұрын

  Very useful app, hope it will continue to be updated

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  @georgevgenis14947 ай бұрын

  Hi! I saw the app at the site and I was very interested in it. But after also watching this video, I was wondering about the use of it. Do you use it before roasting or it is a general algorithm to know where you are going and what to expect from different roasters? Maybe if you have sample roasted a coffee to use this tool to scale up for production?

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  @stevenabbott36857 ай бұрын

  I, and others, use it to explore "what if's". For example, I wanted to know if complicated multi-step roasts can be accomplished by 2-step roasts - which I why I added the 2-step output. I also think it helps explode a number of limitations with current roasting setups. So, rather than wave one's hands to talk about roasting, the model lets you see what is and isn't important in a roast. I've learned a lot from it and have realised that "first crack" is a non-event that should be called "last gasp". I wrote an article on this for Barista Hustle and, not surprisingly, it caused some fuss. First crack is supposed to be fundamental, yet the evidence is overwhelming that it's incidental. How to replace it? With a CO2 sensor that signals the onset of "chemistry".

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  @georgevgenis14947 ай бұрын

  @@stevenabbott3685 But isn't the CO2 release connected with the first crack? It is very interesting not to connect a very delicate procedure with an event (FC) that it is debatable and not easily distinguishable but then again, development time is still mallard reaction. Αny link for the article at Barista Hustle?

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  @stevenabbott36857 ай бұрын

  ​@@georgevgenis1494 Plenty of roast don't crack, maybe only 10% of beans crack anyway, and there is no reason for CO2 onset and first crack to be strongly related. So let's switch to the significant signal, when significant chemistry is happening to the beans rather than an indirect signal that is only used because it's simple ... and because people assumed that the crack was significant whereas it's a last gasp.

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  @GBRoasters2 ай бұрын

  @@stevenabbott3685 Couldn't agree more. That's why you see most roasters smelling coffee vigorously on either side of the first crack to smell the chemical reaction rather merely waiting for the FC and other physical observations.

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  @stevenabbott36852 ай бұрын

  @@GBRoasters Thanks for that. It's funny that in all the papers I've read, roasting videos I've watched and all the conversations I've had, no one has mentioned smelling the state of the roast. And that's a criticism of myself. It didn't occur to me to step outside my science box (focussing on CO2/CO chemistry) and wonder whether some sort of "aroma sensor" (other than the skilled human) could detect significant moments in the roast. Thanks for getting me out of my own bad thought habits! Steven

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  @aliciahaab8258 ай бұрын

  Thanks for the informative video. Would you send me the articles you used as references. Thanks

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  @stevenabbott36858 ай бұрын

  The Scheutjens-Fleer theory has been around since the 1970s so there's an extensive academic literature behind it. There's no single paper that captures all the above. Steven

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  @Skunkhunt_428 ай бұрын

  Worda cant express the value you have brought me for no cost over the years sir. Thank you for all you do. Also, i share your modules to collegues to increase their understandings which has been useful for my whole team!

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  @stevenabbott36858 ай бұрын

  Thank you for your kind comment - it encourages me to continue to help as best I can. Steven

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  @rezagholami792910 ай бұрын

  Thanks for you informative presentation. I was wondering if this concept is applicable in the case of interfacial adhesion in polymer blends, like interfacial adhesion between rubber particles and the matrix in the rubber-toughened polymers.

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  @stevenabbott368510 ай бұрын

  Very much so. I created that video a long time ago. If you want an up-to-date guide then my Sticking Together book is affordable via Amazon and covers a wide range of issues, including core-shell rubber spheres in epoxies.

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  @debanjanbhattacharya195611 ай бұрын

  Where can i find this graph making app? I need it very badly for a project

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  @stevenabbott368511 ай бұрын

  It's here: www.stevenabbott.co.uk/practical-surfactants/cmc.php. Good luck!

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  @user-ro5ed1jh2s Жыл бұрын

  Determining molar volumes is difficult in polymers. For example, a unknown molecular weight of a polymer be anything between 1,000 to 10,000 g/mol. Is there a way to still determine the solubility parameters if we cannot determine the molar volume?

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  @richardvonmannstein7610 Жыл бұрын

  Good evening.Very interesting video. I am not sure to have understood the peel strength. Considering a lap joint where the adhesive forms a plan xz and we apply a load along z direction. Is this CORRECT that the shear strength corresponds to the tensor Tyz? and the peel strength to the stress tensor Tyy? Or how do you quantify numerically the peel vs shear strength? I am currently studying on project to assess the bonding strenght in between a multi-material Additve manufactured piece. I am now making a Comsol modelisation so as to provide hopefully the purest shear strength possible for a lap-joint test. What do you think about it?

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  @stevenabbott3685 Жыл бұрын

  If you have the luxury of doing real calculations with, say, Comsol then you don't need these simple apps. As I say many times, "Adhesion is a property of the system" so knowing the system is the first requirement. In my simple apps I merely choose systems that have tractable formulae because I'm not smart enough to write anything that involves Finite Element stuff. Additive manufacturing is often hugely disappointing because interlayer adhesion can be catastrophic ... often because there's insufficient time/temperature to get polymer entanglement across the boundary. Certainly fused filament objects are often hopeless: temperatures high enough to guarantee entanglement make the whole part sag. Go to a lower temperature and the part stays the right shape, but entanglement is insufficient - I had to read a bunch of papers on the topic. So I don't think my apps help you directly, but if they help emphasise "system" thinking then they'll have achieved something!

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  @corinneboe.198 Жыл бұрын

  for the welded pieces of distinct material can we also talk of bonding strength? Is the developed adhesive theory also relevant?

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  @stevenabbott3685 Жыл бұрын

  If the weld is perfect then by definition we have a single piece of material and then "adhesion" is just the yield strength of the material - though I've never needed to know the fracture mechanics of how concentrated stresses get along the weld line. And if the weld is imperfect, say with a Griffith crack, then it's all about crack propagation. All way outside anything I know. Sorry!

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  @user-ro5ed1jh2s Жыл бұрын

  Why can't you cryomill polymers to powder them for packing in the IGC. Is that because they have non-uniform dimensions and estimating the particle size is difficult? This stems from needing to understand very strictly what "h" is?

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  @stevenabbott3685 Жыл бұрын

  I don't know the answer! I suppose for starters, most of don't have a convenient cryomill. But I think that you're right about "h". When you have a coating of a few μm on a larger particle, you can work with a reliable "h". But if you have a particle of uniform 10μm, we somehow have to change the equation to take into account spherical diffusion. And if there's a broad particle size distribution, that gets harder. But it's only "harder" not impossible. Maybe you can crack the problem and, as I said in the video, change the world of diffusion measurement forever!

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  @niklausory8747 Жыл бұрын

  Thank you for this video. So all the values we find in the literature about bonding strength measuring shear load at fracture by lap joint norm astm D1002 are highly inaccurate? if so perhaps this could be fixed if a factor between the measured value ( the sum of shear and peel value) and the only shear stress would exist?

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  @stevenabbott3685 Жыл бұрын

  They are a (hopefully) accurate measure of what the test provides, but they are otherwise highly misleading. And if they quote numbers such as X N/m2 then they are wrong because although the N are correct, the m2 are wrong because only a small part of the joint has experienced the stresses. In the book I talk of a few attempts to work out the "real" adhesion of the same joint measured using different techniques by experts ... and they simply can't be compared. A double lap joint does a better job at measuring shear failure adhesion, but it's a lot of work and it still tells you surprisingly little about what's going on - because Adhesion is a Property of the System. It's always better to do a test that relates to the specific failure modes experienced in your real application. Such tests won't be ASTM, but they will be much more useful.

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  @kingkaruehat1086 Жыл бұрын

  really clear. i want to know what is name of this app how to know C1 C2 Tg

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  @stevenabbott3685 Жыл бұрын

  The app is at www.stevenabbott.co.uk/practical-adhesion/wlf.php with an improved one at www.stevenabbott.co.uk/practical-adhesion/WLF-K.php. Although you can automatically fit C1, C2 and Tg, the point of the app (especially the newer one) is that you play with the parameteres to get a good-looking single curve - or, sometimes, the best-looking curve even if it's not super smooth. This is to help gain an understanding of what it all means.

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  @kingkaruehat1086 Жыл бұрын

  @@stevenabbott3685 thank you verry much . Do you know how can i get master curve if i have creep conpliance data ..

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  @nvl6880 Жыл бұрын

  Thanks, wonderful work, and great explanations.

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  @hashbrown4231 Жыл бұрын

  Really clear explanation professor, Thank you!

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  @user-kv8ts9qv3i Жыл бұрын

  Thank you professor. This is really a brilliant online software to illustrates each phase❤

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  @erharddinges8855 Жыл бұрын

  Would be very interesting to combine this APP with the ARTISAN roasting software.

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  @stevenabbott3685 Жыл бұрын

  Yes.By "combine" my priority would be to calibrate the app against a real Artisan chart then to validate it by changing conditions in the app and seeing what happens with the data from Artisan. But there are some complications. First, the app has its flaws which are steadily being fixed. Second, as I mention, the values measured by Artisan don't seem to me to be "real". Those with fancy external air supply roasters have a real IT so the app should work pretty well. But the majority have measured parameters that make little sense to me. The most recent version of the app has the TBT. I'd hidden this in previous versions because I didn't have confidence in it, but some academic reasearch suggests that it's correct. We all have a lot to learn, especially me!

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  @erharddinges8855 Жыл бұрын

  The ultimate ​benefit of any roasting software is to make better tasting coffee. But taste preferences are different and roaster probes and measurements are as well. So from a sensory aspect the main question is, what to change in a roast profile to get wanted or to get rid of unwanted aromas. Yes, I think this would be very interesting: to validate it by changing conditions in the app and seeing what happens with the data from Artisan. And for a real workout the question remains whether the roasting machine is able to do the changes.

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  @NotnaRed Жыл бұрын

  Very nice

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  @cruzromeroalexa9551 Жыл бұрын

  ¿Forzosamente se debe realizar la experimentación para encontrar la variable "score"? O ¿Existen algunas tablas que puedan ayudar a verificar esos datos?.

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  @stevenabbott3685 Жыл бұрын

  Sorry to reply in English. Scores are always subjective. That's not a weakness but a strength - you judge the sphere according to your own criteria, so the results are meaningful for your own needs. Steven

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  @vaginaygerard5555 Жыл бұрын

  Many thanks for your work! Would you say the app will be useful to cocoa roasting as well?

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  @stevenabbott3685 Жыл бұрын

  I know nothing of cocoa roasting. I will look it up! The basics of the app will apply to any drum roaster. The details such as water loss or special events equivalent to coffee first crack will be different. It would not be hard to generate a cocoa-specific app, but I need to read the literature first! Steven

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  @stevenabbott3685 Жыл бұрын

  I at last found time to check up on this. If you to chocolatealchemy.com/cocoa-bean-roasting you'll see that they use a coffee drum roaster AND have the same sort of BT curve and you roast to just beyond first crack. The BIG difference is that temperatures are MUCH lower, something like a 150C starting T rather than the 240C that's the default in the app. To allow a bigger range on the slider to set that T I then lose precision for coffee roasting. So I may have to make a separate cocoa version and change the settings and rewrite the next. Thanks for introducing me to another world I'd known nothing about!

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  @yoneln11 Жыл бұрын

  Hello Prof Steven how can i down the ternary diagram after completing it?

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  @stevenabbott3685 Жыл бұрын

  Sorry it can only be screen captured

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  @stephenmiles4191 Жыл бұрын

  Thank you for the video! I have a question that is going off on a tangent but I hope you will be kind enough to answer it… How does one capture a solvent for re-use e.g. acetone after being used on ABS or the new and very expensive Cyrene (dihydrolevoglucosenone) from say polycarbonate or other compatible polymer?

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  @Skunkhunt_42 Жыл бұрын

  All your videos here are gems, not tension your website applets!! Thank you thank you thank you sir!

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  @ShenLong33 Жыл бұрын

  And you're telling me this works? If so, thats genius. I'm trying it, my job will depende on this really working.

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  @stevenabbott3685 Жыл бұрын

  HLD is used around the world for many different types of formulation challenge and I use it myself regularly for problem solving. If you read my Surfactant Science free eBook you'll see that HLD is, of course, over-simplified and has its own problems, such as polar oils, but it beats all the non-alternatives every time!

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  @captainvlog2 жыл бұрын

  at around 4:40, apparently the opposite is true in real test. More thickness dissipates stresses, however real world test generally show the opposite.

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  @stevenabbott36852 жыл бұрын

  Interesting point - and I don't know the answer. However, I can speculate that a thicker adhesive has a chance to fail cohesively, which is not a mode covered by the app. Because "adhesion is a property of the system" we have to think carefully about the overall effect of any one variable such as thickness, while here I'm only looking at stress concentrations, not the same thing as "adhesion".

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  @wiltherdelacuesta81752 жыл бұрын

  Thank you for the shared knowledge. Where can I find this testing app? Thank in advance

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  @Skunkhunt_422 жыл бұрын

  Very much appreciated sir! Thank you for making and sharing such quality resources!

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  @edgarhidalgo5772 жыл бұрын

  Excelente, gracias. Costa Rica

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  @juliusmccrimmon39422 жыл бұрын

  😝 Promo-SM!

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  @panagiotismougoyannis59762 жыл бұрын

  Very helpful presentation. Many thanks. One question: How can you estimate the HSP parameters of a polymer when you know the SMILES of its molecular unit? Thanks

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  @williambrewer2 жыл бұрын

  Thanks!

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  @Eromox2 жыл бұрын

  good video but your voice volume is low

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  @feranmi91312 жыл бұрын

  Hello, is the software you are using here publically available?

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  @wiltherdelacuesta81752 жыл бұрын

  Hi, did you find it?

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  @vaisakhvm17262 жыл бұрын

  Awesome!!! Loved the presentation...Thank you Prof.

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  @vaisakhvm17262 жыл бұрын

  Simple & clear explanation. Thank You!!!!

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  @lancel11942 жыл бұрын

  Thank you！

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  @stevenabbott36852 жыл бұрын

  In my (free) Particle Science book you'll see that neither D nor O thought that DLVO was a great theory. But I have often had to use this app as a starting point for deeper understanding of various particle phenomena. Steven

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  @indrajitsaha95132 жыл бұрын

  Dear Prof Abbott, Could you please suggest any alternative adhesive of Chloroform to use on ABS plastic items? Thanks in advance.

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  @stevenabbott36852 жыл бұрын

  If you look up the Hansen Solubility Parameters for Chloroform they're 17.8 3.1 5.7. If we assume that this is a good match to your ABS, then solvents with similar values will be good. Interesting, both anisole and limonene are close, with anisole being a surprisingly green/safe solvent. If you wanted a more volatile solvent then cyclopentyl methyl ether is not so bad. You can find some more HSP values and some calculation capabilities from my site: www.stevenabbott.co.uk/practical-solubility/solvent-blends.php Good luck! Steven

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  @Skunkhunt_422 жыл бұрын

  Your vids are a gift sir! Thank you!!

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  @stevenabbott36852 жыл бұрын

  Thanks. Feedback is always appreciated!

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  @Skunkhunt_423 жыл бұрын

  Thank you sir for such excellent content. Is there a way I can buy you a bottle of wine/liquor/beer ? Or a way to donate to your website/book efforts?

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  @ikamso3 жыл бұрын

  Thank you so much! I wish I found this sooner

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  @amianifineug13533 жыл бұрын

  Thank you please code of matlab

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  @stevenabbott36853 жыл бұрын

  You can get the JavaScript code from the app, www.stevenabbott.co.uk/practical-solubility/diff-fickian.php. Right click on the page and choose View Page Source. Search for diff-fickian.js and click on the link for the code to appear. Copy/paste into your own code editor and hopefully you can work out how to translate my code into Matlab. Steven

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  @amianifineug13533 жыл бұрын

  @@stevenabbott3685 thank you

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  @43SunSon3 жыл бұрын

  Question plz. If the temperature is not a constant number, how to use WLF to have the correct Log_at ??

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  @stevenabbott36853 жыл бұрын

  That's the point of WLF. As you change T with respect to Tref, ln_at changes according to the formula.

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  @43SunSon3 жыл бұрын

  May I have a silly question, I got log_at = - 6.5 (using WLF equation with t0=20. tg = -80, c1= 11. c2 = 70). But calculation from your website is log_at = + 6.5 . Did I miss anything ? The t0 > tg, the log_at should be < 0, isn't ? Thank you!

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  @stevenabbott36853 жыл бұрын

  I get confused as to whether you have to add a -ve shift or subtract a +ve shift, hopefully people can make sure they've got the final shift right!

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  @43SunSon3 жыл бұрын

  @@stevenabbott3685 thank you for your reply. If I may ask again. Base on the WLF equation, the calculation result is clear log_at = - 6.5, not + 6.5. However, on your website, you showed the result of "at" use + 6.5 not - 6.5. so I believe I do misunderstand something. Could you please explain it? thank you so much for your time.

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  @mediwise24742 күн бұрын

  HOW YOU CALCULATE C1 AND C2