Differences between revisions 49 and 50
Revision 49 as of 2024-05-23 04:01:39
Size: 12364
Comment:
Revision 50 as of 2024-05-23 04:02:03
Size: 12365
Comment:
Deletions are marked like this. Additions are marked like this.
Line 108: Line 108:
 .153 Understanding [[ https://en.wikipedia.org/wiki/Giant_magnetoresistance | giant magnetoresistance ]]. used for huge spinning platter hard drives '''but NOT_ for [[ https://en.wikipedia.org/wiki/IPhone#Hardware | iPhones ]]'''.  .153 Understanding [[ https://en.wikipedia.org/wiki/Giant_magnetoresistance | giant magnetoresistance ]]. used for huge spinning platter hard drives '''but _NOT_ for [[ https://en.wikipedia.org/wiki/IPhone#Hardware | iPhones ]]'''.

The Matter Of Everything

Suzie Sheehy 2023 West Slope Library 539.7 SHEEHY

1984 born Mildura, Victoria, Australia 2006 BS University of Melbourne 2010 PhD University of Oxford 2015 Royal Society University Research Fellow, Oxford

Author website Wikipedia

  • 011 1895 Röntgen experiment generates X-rays across laboratory from cathode ray tube

  • 014 images wife's hand
  • 016 1897 J. J. Thompson

  • 019 electron
  • 020 Original experiment in Science Museum, London

  • 021 Lewis Latimer carbon filament for Edison bulb

  • 022 John Ambrose Fleming Fleming Valve

  • 024 Brain X-Ray, injected air bubble 1919 until 1960s Godfrey Hounsfield X-ray computed tomography

  • 029 physicist Ernest Rutherford

  • 029 chemist Frederick Soddy

  • 030 Rutherford gold foil experiment

    • 039-40 large angle scattering of alphas by gold foil, dense small nucleus
  • 032 Harriet Brooks, grad student from Ontario, detects "gas" (alpha/helium particles) from thorium

  • 037 Ernest Marsden and Hans Geiger

  • 043 Shroud of Turin medieval forgery

  • 043 14300yo remains in Oregon cabe

  • 047 Photoelectric effect

    • 051 Independent of temperature, not classical
  • 054 Planck quantum "act of desperation" to explain high frequency falloff of black body radiation
  • 055-7 Robert Millikan tries and fails to disprove Einstein, paper 1916

  • 058 Nobel Prizes 1921 Einstein, 1923 Millikan
  • 061 Louis de Broglie wave properties of particles, Nobel Prize 1929

  • 063 Davisson and Germer 1925 experiment, electrons on nickel form nanometer-wavelength interference patterns

  • 063 Sandra Eibenberger 2013 10000 amu molecules form 500 femtometer-wavelength interference patterns

  • 071 Griffith Observatory Cloud chamber, 1936 Alexander Langsdorf design

  • 074 Victor Hess Cosmic Rays 1936 Nobel

  • 075 Charles Wilson glass blower, cloud chamber, 1927 Nobel

  • 079 Magnets, curve measures charge and energy
  • 079 Dmitri Skobeltsyn 5 GeV cosmic rays

  • 080 Carl Anderson Caltech cloud chamber, noisy expansion piston, 425 kW magnet

  • 081 observed positrons predicted by Dirac

  • 082 Pauli, Bohr, Heisenberg considered Dirac's antimatter nonsense
  • 083 Blackett and Occhialini observe electron/positron pair production

  • 083 "Anderson youngest physics Nobel" in 1936 at age 33 ... nope, William Lawrence Bragg in 1915 at age 25.

  • 084 1935 Anderson and Neddermeyer observe muons on Pike's Peak

  • 085 differ from Hideki Yukawa's predicted nucleus-binding pi mesons

  • 085 nuclear emulsion plate better than cloud chamber

  • 087 Bibha Chowdhuri discovers mesons with nuclear emulsion

  • 089 1e18 cosmic rays strike every second, 1 GW; Sheeny silly calculation "3.6 billion kW every hour"

    • actually, 1 cosmic ray is 1 nanojoule, 6 GeV ... not 80,000,000 GeV
  • 089 cosmic rays make Carbon-14

  • 090 Beryllium-10 (half life 1.4MY) ratio to stable ⁹Be dates ice cores and soil deposits

  • 090 ca. 1955, Australian physicist E. P. George measures rock density above Snowy Hydro Guthega-Munyang tunnel with cosmic ray muons using a Geiger counter.

  • 090 ca. 1966, Luis Alvarez ( Adventures of a Physicist, p230-236 ) measures muon density from the Belzoni Champer in the Second Pyramid of Chephren.

  • 091 ScanPyramids Project finds void in Khufu's Pyramid

  • 095 Violin teaser
  • 097 Rutherford hypothesizes neutrons, proton-mass but uncharged
  • 100 visual estimation of radioactive events prone to confirmation bias (observer overestimate)
  • 101 1927: Ernest Walton proposes accelerating charged particles

  • 101 Walton shares lab with Thomas Allibone and John Cockcroft

  • 102 Cockcroft calculates alpha Coulomb barrier 10 million volts

  • 104 George Gamow suggests tunneling means 5 MeV emission, 1 MeV sometimes penetrates, perhaps 300 KeV

  • 106 Metrovick 1930 transformer, Walton rectifier

    • disappointing results
  • 109 Start work on 800KV machine 1932, fail, make 250KV Cockroft-Walton generator

  • 109 Irene Curie and Frederic Joliot bombard beryllium with polonium sourced alphas, mistakenly assume gamma emission
  • 110 Chadwick observes many 8 MeV alphas produced with 250 KeV protons bombarding Lithium 7

    • 7.016003434 amu (Li₇) + 1.007276467 amu (p₁) - 2*4.002603254 amu (He₄) -> 0.018073393 amu = 16.835 MeV/c²

  • 113 Physicist Harry Gove at University of Rochester helped Charles Bennett date his violin carbon in 1977.

    • Used a mass spectrometer to precisely count C-12 and C-14 atoms
    • Calibrated with geological carbon 14, found modern charcoal has 1000 times as much
  • 114 measured tree rings, fossils, mummy cloth
  • 115 measured the Shroud of Turin, AD 1260-1390 with 95% confidence, not 2000yo at all
  • 115 $500G products made with particle beams annually in the US alone (2022 GDP $25000G)
  • 116 ion implantation for integrated circuits, De Beers gemstone color modification
  • 117 Louvre analyzes composition of artwork and historical artefacts (artifacts is US spelling)
  • 118 measure bottles, detect wine fraud

  • 120 Ernest Orlando Lawrence , first major chemistry, wooed by physicist Lewis Akeley

  • 124 at UCB in 1929, Lawrence imagines cyclotron
  • 125 first attempt with 1930 PhD student Niels Edlefsen
  • 126 next M. Stanley Livingston 30 cm diameter. 3000 Vac to almost 1 MeV, then 1.1 MeV 1931 August 3

  • 127 larger machines, 27 inch then 37 inch, 2 MeV
  • 129 deuteron beams coat targets with deuterium, spurious results
  • 131 artificial isotopes, radio-thorium 15.5h halflife, radio-phosphorus
  • 132 MD brother John Lawrence injects radio-phosphorus into mice with leukaemia, cured them, controls died
  • 133 1937 8 MeV 37 inch machine / irradiate mother Lawrence's uterine tumor, she lives another 16 years
  • 134 Cobalt-60, half-life 5.3 years, gamma emitter, 4M medical doses/year

  • 134 Seaborg Iodine-131, half life 8 days, thyroid cancer, diagnostics

  • 135 Technetium-99m 6h half-life, 10M diagnostic procedures per year

  • 138 Relativistic protons gain mass but not speed, desynchronize near a few hundred MeV
  • 139 Synchrotron radiation

  • Betatron, field increases with electron energy, particles orgit at a constant radius

  • 142 100 MeV Betatron, zero to 100MeV 60 times per second
  • 143 10 eV lost per revolution, final energy 99 MeV rather than 100 MeV
  • 143 doubling energy, loss increases 16x, tops out at 500 eV
  • 144 Synchrotron, increase drive frequency with particle energy

  • 147 Synchrotron light source

  • 148 X-ray crystallography

  • 149 Benzene 1929, Penicillin 1949, DNA 1952, B12 1955, Insulin 1969

  • 150 Australian Synchrotron 3 GeV, 500 MHz RF, 216 meters circumference (69m diameter), 14 sectors, 30+ beamlines

  • 152 180 degrees of data in 18 seconds, compared to 40 minutes per angle on benchtop. A range of 50 varied samples can be done in a few hours, rather than years.
  • 152 Without synchrotrons, the SARS-COV-2 structure could have taken years.
  • 153 Understanding giant magnetoresistance. used for huge spinning platter hard drives but _NOT_ for iPhones.

MoreLater

Interesting book? "Hitler's Gift: The True Story of the Scientists Expelled by the Nazi Regime" 2012 by Jean Medawar and ‎David Pyke. PSU 5th Floor Q141.M385

TheMatterOfEverything (last edited 2024-05-24 09:37:13 by KeithLofstrom)