imp

Guess I need more definition: electroluminescence? Implies being luminous through electrical stimulation. The layered system you describe is news to me. Many radioactive substances emit light; you could use one of them. I suggest this facetiously, of course. Still, radioactive tritium IS used to illuminate firearms sights, and possibly is still used in luminous wristwatch dials- I had one years ago. imp

Firearms have propelled objects at speeds often several times that of sound, for a very long time, well in advance of a flying machine. (Ask me about guns!!) imp

Are the terms bronchoconstriction and bronchospasm used loosely as both having the same meaning, or is perhaps the latter more related to muscular constriction of airways resulting from allergic reaction, and the former more closely connected with a blockage of airways from physiological damage or excessive foreign matter/mucous? imp

In today's world, it won't create more corn because the planted corn is hybridized seed stock, genetically altered by changing genes, often, in the case of corn, adding those of e. coli. These seeds are sterile, and produce no corn usable as seed stock. Perhaps I convey the impression that I do not favor hybridization of plants? imp

If your question is not posed as facetious (humorous), "SHM" is usually meant to be "Simple Harmonic Motion". My old Calculus text says the pistons in a typical internal combustion engine move in Simple Harmonic Motion. Do you suppose that is true? imp

Sorry, I guess the two sentences should have been separated to avoid the impression that steroidals are related to paradoxical rebound. In any event, my research on the topic of asthma indicates that it rarely causes death. Nonetheless, when I myself could not breathe due to bronchospasm, I considered the possibility of dying; it felt as though I were drowning. At the time I was taking a beta blocker drug to control hypertension, and learned such drugs should not be used by asthmatics. My doctor denied the connection. I continued the beta blocker, the respiratory problems eventually subsided by themselves, and the various diagnoses several doctors had offered proved false. It was probably aspergillosis or a similar fungus-caused infection. imp

My question is: Does the chupacabra as originally described in folklore really exist? imp

Carbon Tetrachloride was once widely used in fire EXTINGUISHERS to put out fires, before it's toxicity was considered excessive. How then, could it "burn" in the ordinary sense of that word? imp

Rocket Man, I see your point. I guess the "something" I get out of it is personal satisfaction. Still, there no doubt are Engineers who are also Lawyers, and seek to "get something" out of perceived poorly engineered products. I would enjoy discussing hypothetical improvement of various engineered devices, but if no one cares to do so, so be it. imp

The more I've learned about asthma, the less I understand it. Are you asking about drugs because you need treatment? I personally had severe breathing problems, suddenly and with no warning, which required medical help and drugs. Several diagnoses were made; they were wrong. I used broncho-dilators with short term relief. The last diagnosis by a doctor was emphysema. After about 1 year, the breathing difficulty went away, and has been absent 2 tears now. As I understand it, the airways of the lungs are surrounded my muscle tissues which constrict at times to bring cilia closer together to make foreign material removal more efficient. However, this narrowing of the passages can become severe enough to make breathing very difficult. The process is medically called "bronchospasm". Bronchodilator drugs relax the airways, allowing more air flow with less effort. This type of respiratory problem is different from that in which lung tissues have been permanently damaged, such as by smoking. To answer your question partially, I do not favor the drugs which are steroids. Further, nasal sprays often cause a condition known as "paradoxical rebound" in which the drug CAUSES or enhances the condition which it is supposed to alleviate. imp

Yes, sir! Many examples "jump" out at me in everyday use of engineered products, which I guess includes nearly everything. As a start: Vehicular drive axles. For many years, outer (wheel) bearings were removable as units, and replaceable. American manufacturers, and perhaps others I'm not familiar with, dispensed with bearings having inner races and simply use the axle shaft itself as the inner race. A failed bearing thus destroys the axle shaft bearing surface, requiring replacement of a much more expensive, and difficult to obtain part. Perhaps this sort of concern for engineering options is not worth consideration for discussion? If not, what should we discuss in this board? What content will inspire and "draw" interest? I ask because I am vitally interested in engineering techniques and alternative methods. imp

I sense that few viewers or contributors look at and consider examples of either existing Engineering or proposed solutions as posing either poor results or needing improvement through further consideration. In less words, as an Engineer, I look for, and often find, examples of engineering results in products which are poor or improvable, and that troubles me. Would it not be valuable for both up-and-coming Engineers, as well as established ones, to discuss method and product improvement possibilities in this Board? imp

My supervisor once said, "Rubber is magic!". We produced a variety of molded rubber products, and he was a formidably competant Engineer. When asked what he meant, he cited many instances he had experienced where, during what should have been predictable engineering results, rubber had performed feats which were unexplainable! imp

Now, think about this condition, as a brain teaser: What if the cylinders were toothed gears instead of cylinders? imp

A spanner during my informative years here (US) was a type of wrench; I don't think it would make much of a "bang" if it hit my head. Is a "spanner" defined otherwise in Scotland? As an example, we here do not use the word "gudgeon". imp

Esters generally have pleasant perceived odors, true. To explain the physiological process by which humans distinguish between "good" and "bad" smells might be outside the scope of a simple science thread; it is certainly beyond my ability, sorry. Still, we should be aware that cultural differences determine to an extent what may be an acceptable smell to some, while it is disagreeable to others. For example, some like the smell of gasoline; many do not. Sorry to not be of more help. imp

A detonable material, such as ammonium nitrate for example, dissociates extremely rapidly into its basic constituents. This process is generally referred to in terms of "detonation velocity". Does anyone have some ready information regarding what means are used to determine detonation velocity? Is it actually measured? I cannot imagine laying out a mile-long length of detonating cord and measuring its "disappearing time". imp

1) Look up molecular weights of constituents of water (H2O) and air, N2 and O2, mostly, and think about what addition of water molecules to a given volume of air does to its density.............or, 2) Ask any airplane or glider pilot; they will surely know! imp

Now, in addition to rising or falling, air contains moisture (water vapor). So, tell us which air you believe to be heavier, moist air containing a lot of water, or dry air, containing no water? imp

YT, while I'm thinking of it, (old age dementia, you know), many pyrotechnic mixtures require a bit of sulfur to enable the mixture to take fire from the "spit" of a black powder fuse. One that comes to mind is the commonly used potassium perchlorate-aluminum mix; without a dash of sulfur, it's very difficult to initiate. How does the presence of sulfur allow the reaction to begin so much more easily? imp

Thank you for the information, Rocket Man. My concern for use of electronic sensing of speed difference between front and rear wheels, and then applying and releasing an electromechanical clutch, is how fast (repetitively) do you want the system to respond? If applied and released rapidly, the effect might be like our "ABS" systems which supposedly stop a vehicle more quickly. Incidentally, a new mandate here requires ALL new passenger vehicles sold in U.S. in 2012 and beyond be equipped with electronic stability control! imp

Possibly close to ultimate, the U.S. military has experimented with a means to render a vehicle invisible to the human eye. This is achieved by scanning the terrain behind the vehicle, then projecting that "view" across the front, or visible part, of the vehicle, thereby making it appear the same as the view behind it. (??!!!) imp

Some forms of itching, especially whole-body itching, are symptomatic of certain serious diseases, such as biliary cirrhosis, a life threatening illness. Widespread itching not attributable to external cause, such as poison ivy, insect bites, etc., should always be checked out by a medical practitioner. imp

Something like superheated gas? Remember also, some solids do not become liquid upon heating, but rather become gas directly. imp

is a trend nowadays. I know of several schemes that have already been employed in production, not experimental or prototypes, to allow for speed variation between front and rear wheels. The AWD mini-vans of early 1990's, Ford and Chevrolet, offered as optional, used differing approaches. Similarly, SUV's are being sold with AWD. The earliest I recall here in the U.S. were called "full-time" 4WD. They were, typically, the Ramcharger, Jeep, and Blazer. These used a transfer case containing a third differential, and were driven using a chain, which seemed to be the "weak link". Full-time died out, but AWD resurrected it, basically. GM used a fluid clutch in the transfer case to allow "slippage". Ford opted for an electro-mechanical clutch which applied automatically as a difference in wheel speed between front and rear was sensed. Which system has proven to be the best? I personally lean toward the fluid clutch myself, since after all, if they are suitable for the best washing machines.............! imp