Recent content by chemaddict

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    Programs for Grand Canonical Monte Carlo

    In my work, we use an in-house developed code for various ensembles, but I was told that LAMMPS http://lammps.sandia.gov" was working on supporting the grand-canonical a little while back. I haven't used LAMMPS personally, but it is highly parallelizable (sp?) and is among the better (albeit...
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    Standard Error of Replicates, Each With Standard Error

    I'm sorry about the confusion. I don't mean to be patronizing in any way, but I think a simpler analogy might be much better. Say, for instance, that I am interested in the speed a ball rolls down a large hill. Somehow, I can measure it every 1/2 second as it rolls. I then calculate a...
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    Standard Error of Replicates, Each With Standard Error

    So I have a situation that I keep confusing myself with: I am running a computer simulation that, after a set number of iterations (a block) will output the running average (mean) of a property and the standard error based on the previous blocks. So, as the simulation runs, these standard...
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    Replacing LED Bulbs with Different Wavelengths: How Difficult Is It?

    Thanks for the replies. I do see that each of those different wavelength/color LEDs listed on wikipedia has a different voltage range. While some of them overlap, I agree that the results would be unpredictable at best. That said, http://www.instructables.com/id/Infrared-LED-Flashlight/"...
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    Replacing LED Bulbs with Different Wavelengths: How Difficult Is It?

    I am not an electrical engineer. Ok, so I am interested in taking a cheap LED flashlight or headlamp (which I don't have yet) and identifying and replacing each individual LED bulb with an LED of a particular wavelength. I've seen you can buy LED's over the internet in bunches so that's no...
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    Possible explanation for the exothermic reaction during electrolysis of water?

    I'm curious to know if you could offer more specifics as to what all is being measured? It's hard to say based on what you've told us. Are you keeping track of the temperature of the liquid solution? Does it drop when the evaporation occurs? If this is your...
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    Possible explanation for the exothermic reaction during electrolysis of water?

    Like the other posts, I can only offer suggestions of what your problem may be. First, I believe K2CO3 will turn your solution basic, so pay attention to the pH of the solution because your electrolysis half-reactions will be different in an acid solution from a basic solution. See...
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    Chemical Burn no marks or redness?

    To be honest, it is possible, but probably not very likely in my opinion. I don't mean to be rude here, but I think you are asking if this pain is a common occurrence due to everyday contact with chemicals. Obviously we don't know your history, and I am not a medical doctor, but everyday...
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    Professional Licensure - Worth it? (USA)

    Preface: This is aimed mainly at professional chemical engineers in the United States. I'm about to finish my ChEn program and I was told it is a good time to take the FE exam to begin the professional licensure process. I understand the benefits of professional licensure in a broad sense...
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    How Do You Calculate the Bottoms Ethanol Fraction in Distillation?

    I am lacking some resources now to fully answer your questions, but here is what I can tell you for certain: -Volume fractions are different from mole fractions, especially when molecular weights and densities differ. Wolframalpha.com can help you get molecular weights and densities. -The...
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    Melting Plastic and Manufacturing

    If you do try to make them in your mold, there are certain types of plastics/polymers that can be melted. Basically you have thermoplastic polymers and thermosetting polymers. Thermoplastic can be melted and reformed, but don't use a direct flame or they might catch fire. A simple one to use...
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    AC to DC Converter for Electrolysis hobby

    An important note: While NaCl may seem like a good choice because it's ubiquitous, you have to realize that you will produce H2 gas and Cl2 gas, NOT O2 gas with it. This has to do with the electrode potential of the half reactions (and this is an EE forum so I'll stop there). As far as...
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    Problem On Designing A Sheel-And-Tube Heat Exchanger

    If you still need help on this I know something about heat exchangers. Unfortunately I'm not sure exactly what methods you're using or what the variables R, S, F represent. Please give a little more detail on those and I'll try to help.
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    AC to DC Converter for Electrolysis hobby

    Thanks for the pics and advice! That is very helpful info. I was actually thinking epsom salt (a hydrate of magnesium sulfate) for the electrolyte. Also, I don't think the platinum electrodes are necessary, they just work best. I'm looking into graphite actually and I was thinking of...
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    AC to DC Converter for Electrolysis hobby

    Hello All, I am interested in constructing a small Hofmann apparatus for electrolysis (as a hobby), like this kind: http://en.wikipedia.org/wiki/Hofmann_voltameter" I am confronted with the choice of either using a bunch of 9V batteries, or some kind of AC/DC rectifier. As I am a...
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