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Everything posted by OldChemE

  1. It's all OK guys-- remember, this is the internet. The great thing about the internet and computers is it lets us be brave enough to type things we wouldn't have the guts to say to someone face-to-face.
  2. There are other aspects that (maybe) are in favor of Aircraft carriers. The Nuclear powered carriers do not have to carry fuel, which allows them to carry large amounts of fuel for both their aircraft AND other ships in their group-- which gives them added flexibility and range. They have been designed to withstand the blast of everything up to and including small tactical nucs-- such as nuclear torpedoes . It is also very, very difficult to punch a hole in the hull of a modern Aircraft carrier, and they don't have to worry much about being attacked by submarines. Unfortunately, I cannot give you any links to support this, as details are still classified, but I was there for a lot of the design work.
  3. Things progress in a way to get better?? Didn't work for the Dinosaurs, and I wouldn't count on it for us either.
  4. A related topic if you want to look it up is Kohlberg's stages of Moral Development. He basically postulated six stages, starting with total ego-centricity (young children) through the final stage where people recognize that there are moral absolutes that apply even without laws. If I recall correctly, he also postulated that not all adults make it to the last stage. I don't have a non-copyrighted link to offer, but I believe wikipedia probably would be a place to start.
  5. OK-- I have to ask. Let's postulate that "A" is the one that lies, and B is the one who tells the truth. If I ask "A" "If you were your brother (sister) would you always tell the truth?", the correct answer would be that B tells the truth, so "A" will lie and say say "No." If I ask B "if you were your brother (sister) would you tell the truth?", the correct answer would be "No", and that is the answer B would give, because B always tells the truth. Since both will answer "No", how can I meet the original challenge of telling which is which??
  6. My wife an I do not permit news programs in our home (and we never have done so). Way too much sensationalism and depressing. Instead, we read. We wait awhile for the news to make it into print-- which usually allows for the really important stuff to rise to the surface.
  7. Velocity-Boy: "You don't get half a card from each stack for one trait." I agree with your point, but your statement isn't quite correct. You receive one full allele from each parent. Those two alleles, depending on the mix of dominance and or recessiveness (and even more complicated for polygenic traits) then determines the resulting phenotype. Thus, for each trait in the offspring there really is one- half from each parent. What I think you were trying to point out is that the expressed trait (the phenotype) will not be an average of the two contributions, with which I fully agree.
  8. I find the idea that we do not possess free will ludicrous. The thoughts I develop and the actions I take originated somewhere in my brain. Whether I consciously thought about it or whether it emerged from some dim back corner without conscious thought or whether or not someone convinced me to do it is immaterial.-- either way the decision to act came from within. That's free will.
  9. Environment, not socialization. Survival in the environment is the ultimate decider as to who survives, hence what brain capability survives. Pardon my pessimism, but as I look at modern society I have trouble believing that typical social interactions could in any way be correlated to improved encephalization.
  10. I too believe that when you are dead you are dead-- there is no afterlife. However, I maintain that Heaven and Hell do exist and most of us will eventually face them. Most of us will sooner or later in our life evaluate who we are and what we have done. Heaven is within the mind-- being satisfied that we did our best and have loved ones and friends. Hell is also within the mind-- knowing we screwed up and that its too late to fix.
  11. I would say applied math in some form is a must. I took lots of physics and chemistry-- which makes sense since I took degrees in Chemical Engineering and Nuclear Engineering. But-- in the end, you're going to need a strong base in practical math in order to make use of the Physics, and Chemistry. Even Biology has a surprising amount of math if you really want to investigate and correlate information. There were many, many times in my career (I'm retired now) when I needed math as much or more than the chemistry and physics, simply because i needed a result I could apply that was properly developed from the theory.
  12. Lots of good advice. In the end-- as cruel as I know this will sound, you have to let the deniers fail/die/or suffer whatever consequences their bad decision brings about. We live in a very protected age. Everything has operating warnings. We have medical miracles. Many, many people, either consciously or unconsciously don't really believe their actions or decisions will have serious consequences. Someone or something will save them no matter how stupidly they may behave. Some people will only change when they have concrete personal proof that they are/were wrong. Cruel, but. I fear, true.
  13. With no real basis, I have often wondered if Deja Vu might simply be a memory timing issue. We have short term memory and long term memory. If somehow an experience slips into long term memory faster than it arrives in short-term, might we believe we have had this experience before??
  14. Very true, but I enjoy playing with the chemical side (probably not surprising for a Chemical Engineer).
  15. Yes, you need to be concerned about molds. But-- if your walls are made of wall-board the standard for many years has been to use a special type of wallboard in kitchens and bathrooms that is mold and moisture resistant. You just want to make sure the paint has good coverage and let the walls dry after each use (I've got a shower in my house that has walls with one original coat of paint, applied in 1991 over mold resistant wallboard, and not a spec of mold yet).
  16. I realize this is an old post-- but gunpowder and firearms design is a topic close to my heart so I thought I would add some ideas. Certainly, a magnetic or other energy source approach to a firearm is within the reach of current technology. This prompts me to toss out some suggestions for the specifications such an alternate approach might want to meet. At a very early point in history firearms were revolutionary-- but since then the development of firearms has been evolutionary-- and there are lots of unique aspects that a new design might want to consider. The energy source: Certainly, any energy source that cam impart sufficient velocity and momentum will do. Gunpowder is particularly well suited to this task. It is easily packaged in the cartridge which means no external power source has to be maintained. It lasts very long times without degradation (100year old ammunition usually works just fine). This gives it a degree of superiority over liquid fuels and external power sources. The projectile: accuracy over a great distance usually requires stable flight and a minimum of velocity loss with distance. This prompts us to want low drag and high mass. Low drag to minimize energy losses and high mass to provide higher energy and momentum. Lead projectiles, although originally convenient because one could make their own musket balls over a fire, work particularly well (regardless of whether or not they are covered by a metal jacket) because lead is a very dense material-- allowing lots of mass in a small package with a small drag cross-section. Your design needs to think about the projectile, how far you want it to go and how much energy you want it to retain over that distance. The launching mechanism: Unless your projectile can be controlled during flight, you need to give it not only linear momentum but also angular momentum about the axis of the direction of travel (spin). This is another reason lead has worked out so well-- it engraves to the rifling, which imparts spin, yet it (and copper jackets) are soft enough that they cause minimal wear to the barrel. And-- a rifled barrel is really a very simple means of imparting spin to a projectile. your design needs to consider how you will obtain stability in flight and how to do so in a way that will be reliable for extended use. Energy impulse: The time duration and peak of the energy impulse has a lot to do with the requisite strength of the launching mechanism. This actually makes something like a rail gun look pretty good, because the acceleration force can me modulated and maintained right up until the projectile leaves the mechanism. This is, in fact, how gunpowder systems work. There are currently about 150 different formulations of gun powder commercially available that have purposely designed burning rates ranging from very fast (essentially an explosion) to very slow (more like solid fueled rockets). This permits each cartridge to be designed such that the gunpowder burn will last until the projectile leaves the barrel and also allows the peak pressure of the burn to be matched to the capabilities of the firearm design. Flexibility and ease of use: This relates to the hobby of reloading. Many people (myself included) reload our own ammunition because it allows us to customize the ballistics of our firearm for whatever purpose or interest we wish. We can tailor our charges for any velocity from barely enough to leave the barrel all the way to supersonic flight (within the pressure capability of the firearm). We can vary the composition, mass and shape of our projectile to suit our interests. Some of us (particularly old engineers) can waste thousands of rounds of ammunition doing nothing be experiment with the variables. The equipment needed is simple and inexpensive. This is why reloading is such a popular hobby even though factory made ammunition is readily available-- the factory loads are very standardized and not customized to a particular firearm and its mechanical tolerances. So-- if you want to design a good replacement for gunpowder firearms, think about whether or not you design will be within the reach of people to tinker and play with. (for those wondering what I do with all this-- I plan to someday have a perfect set of custom loads for each of my 5 rifles-- just for target shooting, since I am not a hunter. So far I've only built and fired about 18,000 rounds, but I still have so very many experiments I still want to try).
  17. "Unsurprisingly" is quite correct. The speed of oxidation with Potassium Permanganate, IIRC, depends on the presence of a medium for the reaction to take place in. Very slow in this case presumably because the tissue was dry. I used to demonstrate this to my Chemistry students by mixing a few grams of Potassium Permanganate with a few grams of skin moisturizer in a small plastic cup. Nothing happens for the first minute or so, and then it burns very hot and very quickly (like a highway flare), consuming the moisturizer and the plastic cup.
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