• Stratospheric Aerosol Injection by Coulombic Hoist

    01/06/2023 at 21:47 0 comments

    last update 06-25-2024; for later updates, see my blog Experimentalist’s Progress, Blogspot.

    An exploration of possible modern uses of clear-weather atmospheric electricity.

    The idea: On clear, calm days, release tiny, negatively charged sulfur particles near ground level (but no lower than 25 cm) and wait for them to rise into the stratosphere on the sky voltage. They should then oxidize to a sulfuric acid aerosol, which is a powerful climate cooling agent if present in the stratosphere. The stratosphere begins 8 km above the surface in the arctic and 16 km above the surface in the tropics (mode= 12 km). At the surface, the electric field of the sky voltage has an intensity of 100 to 200 volts/m, earth negative, with the maximum occurring at 18:00 UTC, no matter where you are. It is part of the global atmospheric electric circuit, which is powered by thunderstorms and other electrified clouds. Solid sulfur can be negatively charged by friction, a process called tribocharging. Tribocharging is already used in one type of powder coating technology. 

    A network of photochemical reactions given here  https://doi.org/10.1073/pnas.1620870114 (scheme 1) suggests that elemental sulfur will change into sulfuric acid aerosols in the atmosphere. (The scheme is presented as applying to anoxic conditions, but in the text, it is presented as describing current knowledge of atmospheric sulfur chemistry.) A fly in the ointment is that an irreversible step is shown going from gaseous S8 to solid S8, and I want reversible, so I am still searching for a rigorous chemical precedent for the supposed transformation. DOI:10.1126/sciadv.abc3687 figures 5B and S4, shows that when suspended in an aqueous solution at pH 6, solid sulfur generates sulfate when irradiated at 280 nm (shortest-wavelength end of the UVB range). That precedent isn’t rigorous either but it is helpful in addressing the question of providing sulfur in solid elemental form.

    If stratospheric temperatures are too low to permit useable oxidation rates, microwave heating using ground-based projectors could be tried.

    To charge negatively, the teflon tube that is standard on a tribo gun will have to be replaced by a tube made with an electron donor, or else corona charging used instead of tribocharging. I calculate that to rise in the atmospheric electric field, a particle needs a charge to mass ratio ("specific charge") greater than 50 millicoulomb/kilogram, which may be another factor requiring corona charging.

    The figure of 50 mC/kg was derived by dividing g, the gravitational acceleration at the Earth's surface (about 10 m/s2), by 200 V/m, and multiplying by 1000 to get the units used in studies of powder-coating physics (and the units analysis checks out).

    Extrapolating from data in Meng et al., 2008, http://dx.doi.org/10.1088/0022-3727/41/19/195207 , 2.3-micron-diameter sulfur particles corona charged at 90 kV should fly. However, a ten-fold smaller sulfur particle will have a ten-fold greater specific charge, giving some margin to allow for discharging on the way up.

    The diameter of the sulfur particle injected into the stratosphere is unrelated to the diameter of the eventual sulfuric acid droplets it produces upon oxidation in the stratosphere, because one reaction intermediate, sulfur dioxide, is gaseous.

    At this time, my best guess as to how fast the particles would rise is 3 cm/s (because I believe I have seen it), which will take them up to the stratosphere in four to five days. 

    Ideal release conditions are low barometric pressure (i.e., rising airmass) but no clouds. This need not be a contradiction in terms if the rising air is dry to begin with. For example, dry polar air warmed by contact with arid ground should rise without cloud formation.

    However, thus far, my calculations have not addressed the fact that the sky electric field weakens with height. At an altitude of 12 km, it is only 5...

    Read more »

  • Dual Use of Technology

    02/06/2022 at 08:03 0 comments

    Reprinted from Stack:

    Is Hackaday an appropriate place to out evil hacks so that people will be on guard against them and thus safer? 

    I can't see going straight to the public police with something highly technical.

    [Dual use means having a destructive use as well as a constructive use, like nuclear energy.]

    Replies:

    KrisKeillor:
    I don't think it's ideal, it would be better to speak to security experts first so some kind of mitigation can be created before the hack is made public.

    If you are the first to discover a poison, at least look for the antidote before you release it to the wild.

    If no mitigation can be found, at that point putting the word out in a security network or even going public is appropriate. It's better to know the threat than be in the dark.

    trigger182 wrote 4 days ago:
    What is your goal?  To raise awareness? Drop it at at a EDU forum if you want to stay anonymous. Shoot an email to a secops company

    Zax3970:
    It is usually also prudent to contact the manufacture of the hardware or software the has a potential vulnerability first. If you get no response or feel the response is lacking the priority needed you can then start contacting the authorities. 

    Here is a good place to start:

    https://www.cisa.gov/coordinated-vulnerability-disclosure-process

    ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

    Note added by DMM: a less obvious threat than nuclear energy is advanced medical technology that, hypothetically, could be aimed either into a patient's body or into the parking lot. 

    https://apl.uw.edu/project/project.php?id=boiling_histotripsy

    Next question: what is the level of evidence needed for contacting the authorities?

  • Better Project Pix

    01/29/2021 at 21:37 0 comments

    1) Another view of Sensor Gun:

    The handle is made from an acrylic artist's palette.

    2) My second white noise machine:

    The board on the left is for signals and the board on the right is for power. It still needs an automatic gain control circuit.

    3) Chord keyset