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mississippichem

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Everything posted by mississippichem

  1. In the vein of other organic chemists I know. You probably know enough reagent acronyms to fill up a dictionary.
  2. I moved this thread to speculations as the "Ether model" has long been out of mainstream physics. Though it is relevant to relativity, the nature of the original post is speculative.
  3. I thought you were the greatest O-chemist of all time!?
  4. You would not be splitting hairs in the context of a formal math classroom. I was aware of the correction Dr. Rocket posted, but given that this thread is for the most elementary level of knowledge transfer my explanation was sufficient and I will stand by it. The original poster doesn't even know what continuity and jump discontinuities are probably, no insult to him. If you wish to criticize me on my lack of rigor then you can, but for what?
  5. Alright, I realize that the more formal statement of the FTC is: [math] \int_{a}^{b} f(x) dx=F(b) - F(a) [/math], for a continuous [math] f(x) [/math] on [a,b]. Everyone knows that. But again, from your new link: I was trying to explain the relationship between differentiation and anti-differentiation that is a result (Corollary?) of the fundamental theorem of calculus simply to someone who didn't have any knowledge of the matter. If my post was somehow incorrect please explain. Your link also states that: if [math]F(x) = \int_{a}^{x}f(t) dt[/math] then [math] F'(x) = f(x) [/math] Which is basically what I stated. I'm not a mathematician so if you are more knowledgeable please clear up my apparent confusion.
  6. Use the combined gas law: [math] \frac{p_1 V_1}{T_1} = \frac{p_2 V_2}{T_2} [/math] So at constant volume we have [math] \frac{p_1}{T_1} = \frac{p_2}{T_2} [/math].
  7. What's the ratio on most Be-Cu tools? It sounds like it's more like copper doped with Be then. Just found out that Be metal can be a skin irritant as well by the way. I didn't know that before.
  8. This could very well be the case for Be-Cu. I don't know in this specific case, it's worth looking into. I'll do some digging in the journal of toxicology and will get back to you on that. I know that Be and many of it's compounds/alloys are Class I carcinogens for a fact though. Stand by...
  9. Not rigorously no. What is the fundamental theorem of calculus then?
  10. Alright, so we've got some good replies here. Even though we had some disagreement; it seems that everyone agrees with the notion that high-school calculus courses lack rigor. I agree for the most part. When I took high school calculus, the focus was also very "symbol-pushy", I did well but probably couldn't have told you what a limit was at that time. I've also noticed that in many of my undergraduate math courses, the higher calculus courses and differential equations, many of my rather intelligent class mates don't really seem to understand what is going on. Every time solving a problem requires additional logic or reasoning beyond an algorithm, some get drastically confused and feel cheated. I'm somewhat mathematically minded, so I do pretty well as far as my curriculum goes, but I feel that I meet too many students that have this problem. For example, I know a lot of students that can compute curl, but none of them seem to have any intuition as to what the curl is beyond [math] \nabla \times \vec{F} [/math]. So how do we fix this problem? We have a bunch of math zombies walking around who can compute whatever operation you need but have no clue what the operations are or mean. When you dump these folks into a higher level chemistry or physics, you get a disaster. Do we teach deeper maths to younger children without symbolic manipulation, like giving intuition about limits, vectors, and things like that? Or is the problem in the college curriculum? Instead of teaching exhaustive use of algorithms do we try to instill mathematical intuition or reasoning? These questions are quite open ended still so don't be afraid to throw something out there.
  11. Beryllosis comes primarily from Be dust and fine particulates, however Be and many of it's complexes are strong candidates to be carcinogens. You're not necessarily okay with alloys either. Beryllium toxicity is not something we really understand well at this point. I wouldn't want to provide a case study for them either. Not to say that you should be scared of all things beryllium. However, I wouldn't want to recommend it's use to anyone unqualified.
  12. You don't want to handle any beryllium. Beryllosis is quite a serious condition.
  13. Don't learn the math. You will quickly cease to enjoy his posts. Ignorance can be bliss sometimes. Curiosity killed the cat to utilize two cliches in one post
  14. You would be better suited with a soluble bisulphate or sulfate like sodium sulfate and acid. Do you really need sulfuric acid though? The process will not be pretty.
  15. So there's been talk around the internet for a while now about what is wrong with mathematics education in the USA. Lockhart's Lament, is a good read if you want a good synopsis of some of the ideas that have been floating around. I thought this would evoke some good forum discussion. One problem I see is that much of the necessary mathematics for a good high school science education get introduced way too late, or not at all. Take for example the calculus/physics problem. Many high schools don't introduce calculus until near the senior year so students never get a chance to take a good physics course. Instead they get a primarily algebra based physics course that may teach some good things but doesn't do much to really ingrain the fundamental concepts from a mathematical standpoint. I remember taking physics and calculus my senior year of high school. There just wasn't much to the physics class really. I'm sure some schools do this differently, but from reading around this seems to be a fairly common situation around public schools in the US. This also sets up a situation where high school students don't get any mathematics above differential (and some integral) calculus. So what can we do to fix such a conundrum? Or maybe, what is the problem? Are we introducing algebra too late? Or are we spending too much time on arithmetical computation in elementary schools? I think the problem is that we have basically no specialization of curriculum in our secondary schools, most of the other problems are corollaries to that. I'm speaking quite generally here, I just wanted to hear some thoughts from the mathematically minded of SFN.
  16. I agree with your general notion of wisdom. I would phrase it differently though. I would say: Wisdom is the ability to have the foresight to combine knowledge with experience in order make the most logical decision in a given scenario. An intelligent person has the ability to solve problems. An experienced person has solved similar problems before. A wise person knows how to combine his knowledge and experience with the knowledge and experience of those more knowledgeable and experienced to get the desired outcome. A wise person knows when to say "I know enough to know that I'm in over my head, let's consult someone or something for correction/guidance." In that sense, wisdom is knowledge strongly coupled to experience and humility. Actually an interesting question in my opinion though. Those who are religious might give a very different answer because most religions have their own definition of wisdom.
  17. Shows how scientific theories are in fact constantly being diced/cut/edited/scratched and updated. Many who are skeptical of the scientific process would benefit from reading more about modern controversies in science. This is a prime example of how the peer-review and experimental repetition process tends to sort out problems over time. It is a sort of "evolution of information" to grossly abuse a metaphor. Useful ideas that reflect reality are "selected for" and tend to reproduce spin-off ideas, whereas not so solid ideas tend to die out. Nice link. Many here need to read it.
  18. I think many students get confused by the calculus notation. So I decided to post the fundamental theorem of calculus symbolically and explain the symbols: [math] \int \frac{d f(x)}{dx} dx = f(x) + C [/math] Basically this says, that if you take the antiderivative (indefinite integral) with respect to x, [math] \int (...) dx[/math], of the derivative of a function of x, [math] \frac {df}{dx} [/math], then you get the original function [math] f(x) [/math] whose derivative you took the anti-derivative of (The big [math] C [/math] stands for any constant term that may have disappeared from taking a derivative) Here is a simple example: We have a function, [math] x^2 + 2x + 3 [/math]. Lets take the antiderivative of that function (don't worry about how I'm computing this, just try and follow the concept): [math] \int \left ( x^{2} + 2x + 3 \right ) dx= \frac{1}{3}x^{3} + x^{2} + 3x + C [/math] Alright, so now lets take the derivative of the right side of that last equation, (we can't derive the C really, just hang with me here). [math] \frac{d}{dx} \left ( \frac{1}{3}x^{3} + x^{2} + 3x \right ) = x^{2} + 2x + 3 [/math], so know we have the original function again! I hope I'm not confusing you with the notation. Here you can see though, how the derivative and antiderivative are really opposite operations. Take a derivative of a function, take the integral of that derivative, and you are back to where you started. Had we differentiated the original function first, then integrated, we wouldn't have recovered our constant term though. That's a different lesson though, (definite integrals). I'm not a mathematician like some of these guys above, but this is how I think about these things as I use this math quite often. That gives new meaning to the phrase "numerical integration". Now days in the 21st century we've advanced to being able to hit the "integrate between __ and __" button in spec. programs at least. What's really appreciated is the automated Fourier transform!
  19. There were many jewish messiahs around that time. The jewish people were quite upset about roman control and there were many spiritual leader types that rose up to the challenge. I wouldn't be surprised if there was a guy named jesus from nazareth who was one of these messiah types or a jewish spiritual leader.
  20. I'm thinking the same. This guy doesn't have any evidence or good arguments. He gets pinned in one thread, so he starts another like we aren't going to go after him in a new thread. C'mon man, this is just getting silly. Ever notice how prevalent back problems are in humans? Our backs are incredibly poorly designed for upright walking. Either we evolved from a species that walked on all fours, or God is a horrible engineer. What use does the appendix have? I'm not letting you ignore this one. Address it. You've yet to offer any argument for any of your numerous threads. Your empty statements are not getting anywhere with any of us. If you really want to convince us, put some effort into your arguments. How would you like it if I came to your forum and posted: "Creationism is wrong, there is no such thing as a God" You would think that I didn't have any better arguments.
  21. Alright, so what was the drug? Several people have asked you, this is my second time. I'm sorry if my accusations of you being psychologically ill offended you, that was not productive. I meant it in sarcasm. You must realize though that from an outsider's viewpoint (remember we don't know you in real life), you do appear to be on a paranoid rant. If you could so easily accomplish this feat on your own, then why did you post a thread about it? You admitted that you have had the answer for sometime and have been pulling us along to test us. Where do you get off to this? Tell us what the drug was if you want to save any infinitesimal amount of credibility on this site. Your intent is questionable at best. You didn't want t use a camera. I think you don't know what the drug is, and you fabricated this entire story for some sick reason. I could be wrong, but I will assume such until you tell us what the drug was.
  22. Its worth mentioning that last year, two chemists from China fabricated some x-ray diffraction crystal structures. They took an established compound from the literature and basically superimposed different atoms on the crystal structure in order to claim they had a novel crystal structure. Their results were published in a Wiley-Interscience journal. They got away with it for a while until someone noticed that their calculated unit angles were not allowed by crystal packing rules. The two chemists' careers were ruined, they were banned from publishing in many journals and I believe they lost what grant money they had IIRC. We have zero tolerance for scientific fraud in the professional world. If you fabricate data, you will be found out. There is no one scientist smart enough to fool all of their peers in the field. Eventually someone comes along with a nose for BS and the fraud perpetrators get sacked. Experiments get reproduced all the time. Lets say someone reports a new compound. I might be interested in making a new derivative of that compound. So first I try their reported procedure out to make their compound, before I try my new alterations out. If their procedure doesn't work, I will assume it is my fault and seek the consultation of a more experienced chemist. If he can't make it work, then perhaps we've found a mistake [or a rat] so we report to the journal and perhaps even publish a correction. This stuff happens on a daily basis.
  23. Having done this myself, I second that opinion.
  24. Start a blog. like Imatfaal stated, you are preaching to the choir here. Most of us are athiests, agnostics or rational [scientifically minded] believers. This is a discussion forum, and you really never offer anything to discuss. Alright, fundamentalists are foolish, we get it. Move along, nothing to see here.
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