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Description and Specification of Graphene - 0 views

www.techinstro.com/graphene

graphene

shared by techinstro com on 16 Aug 22 - No Cached
  • techinstro com on 16 Aug 22
     
    Graphene is a single-atom-thick sheet made from combined carbon atoms. The carbon atoms are bonded together to share electron in a hexagonal, honeycomb-like structure. It is a single atom thick layered 2D material ever discovered in the world. It is made up of a hexagonal lattice pattern of carbon atoms in a monolithic honeycomb-like structure. It is a layer of SP2 single bonded carbon atoms arranged like a chicken wire mesh. It is 200 times stronger than stainless steel (SS) and 100 thousand times thinner than the human hair. It is the slimmest and strongest compound available on the earth. Anybody would be amazed when they know that we have found a material which is harder than diamond, yet lightweight, stronger than steel, but also highly flexible, and this material can be mined from the earth as it occurs naturally. It is yet thin enough to be mistaken for a saran wrap. Apart from the optimum physical properties, the other features are also impressive. Properties of Graphene These are some prominent features which make it a hi-tech material: Excellent Electronic Conductor Chief electronic property makes it an efficient Zero-Overlap Semi metal and gives it sufficient electrical conductivity. Carbon atoms possess typically 2 electrons in the inner shell, and 4 electrons in the outer orbit, total 6 electrons. Although conventionally, the outer 4 electrons in carbon can connect with another atom, each, the atoms can form a 2-dimensional bond with three atoms per single atom. This leaves an electron available for electronic conduction. Such electrons are known as 'Pi' electrons and found above and below in sheet. Ultimate Tensile Strength Mechanical strength is another prominent property of the material. It considered as being the foremost most robust material ever discovered, owing to the 0.142 Nm-long carbon bonds. It also possesses ultimate tensile strength, measuring 130 Gigapascals (or 130,000,000,000 Pascals). Compared to the tensile strength of industr
Todd Suomela

Amateur Science and the Rise of Big Science | Citizen Scientists League - 0 views

citizenscientistsleague.com/...ce-and-the-rise-of-big-science

science amateur professional success citizen-science history government funding sts

shared by Todd Suomela on 04 Apr 13 - No Cached
  • Several trends came together to increase the professional nature of scientific work. First was the increasing cost of scientific work and its complexity. Scientific equipment became more precise and expensive. Telescopes, like those by Herschel, became bigger and bigger. Also, the amount of knowledge one needed to gain to contribute became increasingly daunting.
  • Second, the universities changed. Pioneered by the German states, which at the beginning of the 19th century was dismissed as a scientific backwater, universities began offering focused majors which trained students in a specific discipline rather than classical education as a whole. This was pioneered by Wilhelm von Humboldt, brother of the famous scientist Alexander von Humboldt, who was the Prussian Minister of Education.
  • Germany, once united, also provided impetus to two other trends that accelerated their dominance of science and the decline of amateurs. First, was the beginning of large-scale state sponsorship of science through grants which were first facilitated through the Kaiser Wilhelm Institute (now the Max Planck Institute). This eventually supplanted prizes as the dominant large-scale source of scientific funding. Countries like France that relied on prizes began to fall behind. Second, was the intimate cooperation between industrial firms like BASF and universities.
  • ...1 more annotation...
  • he final nail in the coffin was undoubtedly the Second World War. The massive mobilization of scientific resources needed to win and the discovery of war-winning inventions such as the atomic bomb and self-correcting bomb sight (with help from Norbert Wiener of MIT) convinced the nations of the world that the future was in large-scale funding and support of science as a continuous effort. Vannevar Bush, former president of MIT, and others pioneered the National Science Foundation and the military also invested heavily in its own research centers. Industrial labs such as those from Bell Labs, GE, Kodak, and others began dominating research as well. Interestingly, the first military investment in semiconductors coupled with research from Bell Labs led to what is now known as Silicon Valley.
shalani mujer

They Effectively Fixed My laptop - 1 views

I love to surf the internet using my laptop, then one day it just stopped running. I did not know what to do since the blue screen error did not disappear though I have tried rebooting my laptop. ...

PC technical support

started by shalani mujer on 10 Nov 11 no follow-up yet
Todd Suomela

Guest Post: Tom Levenson on Isaac Newton as the First Cosmologist | Cosmic Variance - 0 views

cosmicvariance.com/...ewton-as-the-first-cosmologist

sts science history physics astronomy astrophysics

shared by Todd Suomela on 25 Jan 09 - Cached
  • Newton knew what he had done. He was no accidental writer. A parabola, of course, is a curve that keeps on going – and that meant that at the end of a very long and very dense book, he lifted off again from the hard ground of daily reality and said, in effect, look: All this math and all these physical ideas govern everything we can see, out to and past the point where we can’t see anymore. Most important, he did so with implacable rigor, a demonstration that, he argued, should leave no room for dissent. He wrote “The theory that corresponds exactly to so nonuniform a motion through the greatest part of the heavens, and that observes the same laws as the theory of the planets and that agrees exactly with exact astronomical observations cannot fail to be true.” (Italics added).
  • To make his ambitions absolutely clear Newton used the same phrase for the title of book three. There his readers would discover “The System of the World.” This is where the literary structure of the work really comes into play, in my view. Through book three, Newton takes his audience through a carefully constructed tour of all the places within the grasp of his new physics. It begins with an analysis of the moons of Jupiter, demonstrating that inverse square relationships govern those motions. He went on, to show how the interaction between Jupiter and Saturn would pull each out of a perfect elliptical orbit; the real world, he says here, is messier than a geometer’s dream.
Todd Suomela

SkyandTelescope.com - Homepage News - "Pioneer Anomaly" Solved? - 0 views

www.skyandtelescope.com/...17846774.html

astronomy history sts archive data

shared by Todd Suomela on 25 Jan 09 - Cached
  • Turyshev has spent the last several years retrieving archival tracking records from obsolete storage media (those classic magnetic tapes, some of them corrupted) as well as detailed specifications of the Pioneer spacecraft itself from 40 years ago. He likens his searching and discovery to rooting around a dusty attic. "No one told me what I'd be getting into," he says. The Pioneer missions lasted so long that they outlived programming languages and data formats. (The Pioneers were launched in the days of punched cards.)
    • Todd Suomela
      Todd Suomela on 25 Jan 09
       
      Note the long term problems of accessing scientific information in archival formats.
Todd Suomela

Rationally Speaking: The very foundations of science - 0 views

rationallyspeaking.blogspot.com/...ry-foundations-of-science.html

sts philosophy induction about(DavidHume) science probability

shared by Todd Suomela on 08 Mar 09 - Cached
  • The first way to think about probability is as a measure of the frequency of an event: if I say that the probability of a coin to land heads up is 50% I may mean that, if I flip the coin say 100 times, on average I will get heads 50 times. This is not going to get us out of Hume’s problem, because probabilities interpreted as frequencies of events are, again, a form of induction
  • Secondly, we can think of probabilities as reflecting subjective judgment. If I say that it is probable that the coin will land heads up, I might simply be trying to express my feeling that this will be the case. You might have a different feeling, and respond that you don’t think it's probable that the coin will lend heads up. This is certainly not a viable solution to the problem of induction, because subjective probabilities are, well, subjective, and hence reflect opinions, not degrees of truth.
  • Lastly, one can adopt what Okasha calls the logical interpretation of probabilities, according to which there is a probability X that an event will occur means that we have objective reasons to believe (or not) that X will occur (for instance, because we understand the physics of the solar system, the mechanics of cars, or the physics of coin flipping). This doesn’t mean that we will always be correct, but it does offer a promising way out of Hume’s dilemma, since it seems to ground our judgments on a more solid foundation. Indeed, this is the option adopted by many philosophers, and would be the one probably preferred by scientists, if they ever gave this sort of thing a moment’s thought.
  • Todd Suomela on 08 Mar 09
     
    short summary of some probabilistic responses to the problem of induction
seth kutcher

The Best Remote PC Support I Ever Had - 1 views

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started by seth kutcher on 12 Sep 11 no follow-up yet
Sanny Y

The Number One Computer Tech Support Service - 1 views

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shalani mujer

The Number One Computer Tech Support Service - 1 views

Computer Tech Support Service offers the most outstanding computer support service. They have friendly computer support technicians who are very skilled in giving accurate and fast solutions to...

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started by shalani mujer on 12 Oct 11 no follow-up yet
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