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OldChemE

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Everything posted by OldChemE

  1. What's missing from this discussion to some extent is the unique aspect of humans: A high level of intelligence coupled with the instinctive biological drives. This creates a situation where there are three driving forces that can conflict: (1) The instinctive drive to reproduce that pretty much all living things share, (2) The intellectual attraction some people develop that seems unique to intelligent species, and (3) The societal standards unique to individual cultures. This makes it difficult to generalize.
  2. Philosophically, I think it is a matter of national boundaries. That is, until mankind reached the point of identifying as part of a governmental unit, there was little basis for ownership, except, of course, ownership by force. Once a group of people become part of a governmental unit, the land claimed by that governmental unit (i.e. national boundaries) becomes subject to the laws of the region and that inevitably leads to rights regarding who can live where and also conditions regarding land ownership.
  3. We have both cats and dogs-- very different. There is a study of cat and dog behavior that suggests that cats seem aloof because they do not understand social behavior as well as dogs. Details here: https://www.bbc.com/future/article/20210318-why-cats-wont-punish-a-stranger-who-harms-you
  4. https://en.wikipedia.org/wiki/Fahrenheit The Fahrenheit scale (/ˈfɑːrənhaɪt/ or /ˈfɛrənhaɪt/) is a temperature scale based on one proposed in 1724 by the physicist Daniel Gabriel Fahrenheit (1686–1736).[1][2] It uses the degree Fahrenheit (symbol: °F) as the unit. Several accounts of how he originally defined his scale exist, but the original paper suggests the lower defining point, 0 °F, was established as the freezing temperature of a solution of brine made from a mixture of water, ice, and ammonium chloride (a salt).[3][4] The other limit established was his best estimate of the average human body temperature (set at 96 °F; about 2.6 °F less than the modern value due to a later redefinition of the scale).[3] However, he noted a middle point of 32 °F, to be set to the temperature of ice water. Fahrenheit was born in Danzig (in the Polish-Lituanian Commonwealth) This is one, at least, that cannot be blamed on the oddity of English and USA measurements
  5. The original proposition is too poorly defined. Would heart stoppage be bodily death? How long must human consciousness survive to qualify? I had an elderly friend years ago who died at a square dance. His hear stopped while he was talking to friends. He felt his heart stop, got a puzzled look on his face, then then fainted. It certainly appeared that his consciousness survived death by a second or two. But, of course, it depends on how you define "bodily death."
  6. Having taught math successfully in Junior High and High school I though I would have a lot of great examples for you-- but on further reflection realized my best ones were not something that could be generalized. I had the greatest success when I could connect the math lesson to the students' experiences. For example, in my rural area the vast majority of the students have experience with guns and many also have reloaders in their families (people who make their own ammunition). When I first tried to teach statistics I got blank looks from many students, So that weekend I took my test equipment out to the rifle range and measured velocities of 10 rounds of ammo I had built. On Monday I put the data up on the screen and asked the students if the load I had developed was consistent enough for hunting. This lead to a successful lengthy discussion and the development of the idea of mean and standard deviation. The lesson I learned and applied from then on is this: The goal is not so much to make the students think differently, but rather to create a use for the math knowledge in a way that connects to their experiences. I can think back to lots of examples of good teaching tricks, but realize they are were specific to a certain student or group of students. Not much help to what you want.
  7. Sorry I'm slow replying (away for awhile). Fundamentally, Switzerland went with the nuclear option because they had not significant sources of fossil fuels in the country-- they were importing what they needed. Nuclear gave them a degree of energy independence. That, however, was almost 20 years ago, and I have not kept track of how things may have changed since I left the country to return to the United States.
  8. Its not clear that your original premise is true. While menial jobs in many industries have become automated, many service-oriented jobs have been created. Service jobs also contribute to society and are part of the gross national product.
  9. In comparing Nuclear and renewables there was the historical question of scale (how to generate large amounts of energy in small spaces). At the time (60's-80's) the only good options for large generating capacity were hydro, fossil fuel and nuclear. Nuclear was a good choice because good opportunities for hydro were dwindling and, while it has its own sets of problems, nuclear replaced coal-- a benefit in several ways: reduced acid rain, reduced greenhouse gas emissions, and reduced coal tailings (random radioactivity and other localized pollution). I worked for several years as a technology advisor in Switzerland on construction of the Leibstadt Nuclear Power Station. When that project was getting underway the anti-nuclear people in Switzerland argued that the country should opt for hydro. A proposal was actually put together for a hydro plant big enough to eliminate the need for Leibstadt. The dam would have flooded such a large amount of precious wine and dairy land in Switzerland that the country opted for nuclear. In a sense, Nuclear gave us a bridge to the days of efficient renewables.
  10. I too am somewhat confused--about what you are really asking. maybe you need to explain your question further. But-- starting with what you have.... There are not two input values-- in any given equation the value of x can only be one number at any given time. So, there is really only 1 input. For any given equation there might be more than one value of x that satisfies the equation-- but only one value may be used each time you use the equation. In this instance, if x^2 = x/x = 1, then x = 1
  11. Physics - Principles and Application, Douglas C. Giancoli, ISBN0-13-060620-0. The interesting thing about this book is that it covers the physics behind virtually all branches of Engineering. It is a College level textbook that has the unique feature that is it Algebra based instead of being Calculus based. As a result the examples and problem sets are somewhat more closely aligned with the day-to-day of engineering problems as opposed to more research oriented aspects of physics.
  12. Some thoughts from a Teacher's perspective (mine) 1. High Stakes testing. Definitely should not be used as the primary means of determining what a student knows. Frequent assessments (what we call "formative" assessments) work best. In my experience most good teachers do it that way. However, some high stakes testing is important. If a person does not learn to handle some degree of pressure they are likely destined for job failure. 2. The written word. The ability to read is fundamental to almost all of life. Try using as computer if you cannot read well. It also relates to learning. When we read, process information through our brains and then write some of it down (note-taking or doing homework) we learn much better than when we watch a movie. It is true that some people learn well from video-- but not many. There are many different learning styles among people and a good teach tries to activate all the styles: by requiring reading, by doing visual demonstrations, using video clips and even requiring written work. 3. Textbooks: they can now be online-- no paper or pages written upon by previous students. 4. Teaching as a secondary job? Well, maybe if you teach only one class period-- but not efficient or likely. Many teachers spend nearly as much "teaching" time out of the classroom as they do in the classroom. The outside time is when we read student work, correct their work, and try to figure out what they understand or do not understand so that we can appropriately adjust our lesson plan for the following day. When I was teaching math I was working 60 hours a week--just because I needed to check the student homework to make sure the learning was happening. As far as I can tell the rest of your concerns are minor-- even things in the discretion of the individual teacher.
  13. So, modern science disowns its ancestry for commercial interests-- and ancient science/philosophy did not? I think you ought to do some research on ancient societies and ask yourself how the ancient scientists/philosophers had the time to do what they did without needing to work all the time to support themselves. Think about the role of patrons and rulers. The patrons and rulers saw an advantage, commercial and/or political, in supporting the activities. Lets go waaaay back in the pursuit of science and invention. Had the wheel no commercial value?
  14. If you can find it somewhere, look for a Scientific American article "Traces of a Distant Past" by Gary Stix et al published in the July 2008 issue. It traces out human genetic relationships by changes in DNA and uses a mathematical method of estimating times of the changes based on rates of DNA mutation. It is only a small piece of what you are looking for, but it might prove interesting.
  15. Back to the op-- I don't think he will be able to steal this election. Good thing. As some here may realize I am a political conservative who values honest dealing. I had high hopes for the past four years and it most definitely did not work out.
  16. Many such products offgas to some extent early on life and then the levels go down. Think "New car smell." However, it is short lived. I'm not aware of any studies specifically on the health hazards, but because it is a short lived process (new products) I suspect it is not a hazard. If the process were to continue indefinitely I would expect the records to degrade. I am speculating that it is a short lived process because the new car smell goes away fairly rapidly and also I have vinyl records that are 50+ years old that do not seem to have decayed.
  17. So, acceleration is one example where we see seconds squared, but we are not really squaring a second-- its mathematical language. When we say, for example, that the acceleration is 10 meters per second squared we are really saying that the velocity is increasing by 10 meters per second each second. Mathematically this looks likes we are squaring a second but in reality we are not.
  18. I have to be careful how I say this, but... I do not believe God exists-- but, if a God of unlimited power did exist, could not that God have triggered the existence of the Universe in such a manner that everything we can measure with science remains true? If so, then, while there is no experiment or observation that proves such a God exists, there would also be no experiment or observation to prove such a God does not exist.
  19. A very interesting development, but it raised a question in my mind. As you all know, superconductivity was originally achieved by cooling to a very low temperature. Now it has been achieved by applying a very, very high pressure. It occurs to me that these two approaches have a common element-- they both involve moving the atoms closer together than they normally would be at room temperature and one atmosphere pressure. I have no knowledge as to whether distance between atoms is a factor in producing superconductivity-- but I wonder about it. If atomic distances are a factor, this achievement may not bring us closer to practical room-temperature conductivity.
  20. It depends a lot on what you know and how much you are in the habit of using what you know. People who have a solid grounding in math and science often apply their knowledge without ever consciously thinking "now I will do science." When I go to clean the bathroom and look at the available cleaning products my wife has accumulated I find myself considering the ingredients and their possible chemical interactions. 10 years ago a tall pine in our back yard died and looked like it would fall, but I was just packing for a vacation. So I quickly used the similar triangles method to estimate how tall it was and decided that if it did fall it would be just short enough not to touch our glass back door. Sure enough we got back from the trip and it was down, and the tip was three feet from the door. It's just a automatic sort of thought process for people who are accustomed to applying math and science.
  21. Alas, there are many different types of work in Chemical Engineering and I never spent much time on pipe systems, but its nice to get a mention. I, too, was thinking that perhaps the goal was to create a vortex action, but have not been able to come up with a proof that it would work. It wold be interesting to know if anyone has ever actually done an experiment on this.
  22. First, let me say that "simply being creative" is very much more valuable than you make it seem. But, aside from that, There are undoubtedly many novel ideas that a hobby inventor might discover and patent thereby becoming rich and/or famous. The difficulty is that the things that have value depend on what is going on in society and the current state of both technology and the needs of society. To successfully invent you need to be attuned to the needs of society and where those needs are either not being fulfilled or may not even have been yet recognized. A good example is the invention of the tiny plastic clips that are used to close plastic bags (such as in the bread section of the market, at least in the US). Invention has a great deal to do with recognizing needs and being at the right place at the right time.
  23. Oxidation states relate to the electron structure of the given atom, generally taking into account the octet rule. The Octet rule basically says that atoms "prefer" to have 8 electrons in their outer shells (there are exceptions and it is not very rigorous-- but it works). The outer shells of Sulfur are 3s2 3p4, for a total of 6 electrons. By 'sharing' 2 more electrons (from the hydrogen atoms) the atom fulfills the octet rule, but that gives it an electric charge of -2 (2 extra electrons). As these two electrons are from the two Hydrogen atoms, they are now are each +1. The extent to which the electrons are only shared, as opposed to one atom taking and varies. There is a lot more technical detail to that. You should note that the arrangement of the Periodic Table is ties into this, as elements that usually have the same oxidation states are all in the same column.
  24. You might want to approach this differently. How many half lives would it take to get to 30%? If you knew how many half lives, you would then know how many half lives equals 300,000 years.
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