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    CR2032, but with more Ah?

    Ah, for that application, I'd be tempted to try a pair of AA batteries in series instead of the lithium. L91s wouldn't be a good choice (voltage too high), but alkalines should be fine and even NiMH might work. Fresh voltage on the alkalines will be a touch high, but if you've got a bucket of...
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    CR2032, but with more Ah?

    A few numbers around internal resistance: a fresh CR2032 has a rated internal resistance of around 10 ohms, compared with the roughly half an ohm for the CR123. That's about a .1V drop on the CR2032 for a 10mA LED load, and negligible drop on the CR123. Probably not an issue for blue or green...
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    CR2032, but with more Ah?

    All of the CRxxx batteries use the same chemistry, and so should be interchangeable electrically (assuming you are moving up to a larger size). So a CR123 would be an appropriate replacement for a CR2032, at least electrically
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    HDS Systems #23

    The Nitecore grease appears to be a silicone-based grease, which is fine for most rubbers but will cause silicone rubber to swell. Sounds like the HDS O-rings are silicone.
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    HDS: Collection of information about LED options

    The R9050 in the part number of the Niciha LEDs is a CRI code denoting an Ra (CRI) of 90 CRI minimum and an R9 value (rendering of the red swatch from CRI) of at least 50. Actual measured CRI will be higher, but may vary slightly from sample to sample and with drive current; it's likely around...
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    The Malkoff Front Porch

    Nope. The M31 uses a boost converter, which means that the battery voltage must be lower than the ~3.2V of the LED. So a 14500 will fry the LED in an M31, but a CR123, or one or 2 AA batteries (a single L91 or a pair of NiMH work well) are fine. But for a 14500 in that same host, you could...
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    Daylight vs 5000-6500K LEDs

    Yep. This has been known about since the 1940s: Note also that there are regional/cultural preferences for CCT as well - some parts of Asia prefer very high CCT illumination, while US consumers tend to prefer low CCT illumination.
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    Landscape Lighting Path Light Problem

    Those LEDs look like a midpower LED soldered to a carrier board, and then the whole thing covered with a glob of encapsulant. As the LEDs are on carrier boards, plenty of options assuming you can get the old LEDs and boards off the fixture. Just make sure you get the proper voltage alternative...
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    Is D-9 tool steel magnetic?

    Stainless steels generally are specified by the alloying elements, with the balance (typically implied) being iron. So since the listed alloying elements add up to ~40%, the remaining ~60% is iron.
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    Is D-9 tool steel magnetic?

    Other than the balance (~60%) that's iron? That said, the alloying elements often modify how magnetic the material is, so hard to say if D-9 is still magnetic after alloying
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    Energy : Production, Storage, Efficiency, Solutions seems to indicate that the battery in question is a type of flow battery, and the "special sauce" is primarily in the electrolyte solutions.
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    The Malkoff Front Porch

    M31 or M61 in a VME head?
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    Energy : Production, Storage, Efficiency, Solutions

    There's easily 100 square miles of area for solar panels in interstate highway medians (assuming a 20' wide strip down the center of 55% of the Interstate highways in the US - you could probably double that depending on how much clear area you need). And don't forget parking lots - that area is...
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    U.S. lithium production

    It's bit more complex than that - the height of the front end these days comes from pedestrian crash safety requirements (need enough room for the hood to be able to deform on impact), and for the F150, I strongly suspect Ford wanted to maintain the "family" look, which limited their...
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    U.S. lithium production

    Engineering 101 says you can make your resources go farther by being more efficient with them, which does indeed mean lighter, more aerodynamic vehicles. But Business 101 says "go where the money is", and in the US that's trucks and SUVs. It's not a coincidence that the automakers have started...
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    U.S. lithium production

    This is probably better suited for the "Energy: Production, Storage, Efficiency, Solutions" thread (perhaps a moderator could move it, along with a copy of the root post), but here goes There's 3 basic ways of doing ground-source heat pumps: * Open loop (use an existing water well, and pump the...
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    U.S. lithium production

    Air to water heat pumps are commercially available, and are likely more cost-effective than a ground-source heat pump (even in colder climates - the higher efficiencies that come from the relatively stable ground temperatures at the extremes of the summer and winter are somewhat offset in the...
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    Repairing A Wireless Towing Light Kit

    Given the almost complete lack of protection circuitry on that board and the direct connection from the control and power ICs to the outside world (and automotive electrical systems aren't known for being benign electrical environments), I suspect that at least one of the ICs has been fried...
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    High CRI and high lumens… have the cake and eat it too?

    I'm not sure how much confidence I would have in those output numbers - the Cree XHP50 is rated for about 2300 lumens for a top bin running at maximum rated current, and that doesn't count the losses in the reflector or lens. OTF lumens for an XHP-50 with realistic binning are going to top out...
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    The US legislation that imposed the efficacy requirements for lighting that precipitated the phase-out of incandescent lamps was the Energy Independence and Security Act of 2007 (full text: and wikipedia has a summary at...