Last year, we brought you a story about the BhangmeterV2, an internet-of-things nuclear war monitor. With a cold-war-era HSN-1000 nuclear event detector at its heart, it had one job: announce to everything else on the network than an EMP was inbound, hopefully with enough time to shut down electronics. We were shocked to find out that the HSN-1000 detector was still available at the time, but that time has now passed. Fortunately [Bigcrimping] has stepped up to replicate the now-unobtainable component at the heart of his build with his BHG-2000 Nuclear Event Detector — but he needs your help to finish the job. Continue reading “Replicating A Nuclear Event Detector For Fun And Probably Not Profit”→
If you think about it, you can’t be sure that what you see for the color red, for example, is what anyone else in the world actually sees. All you can be sure of is that we’ve all been trained to identify whatever we do see as red just like everyone else. Now, think about animal vision. Most people know that dogs don’t see as many colors as we do. On the other hand, the birds and the bees can see into ultraviolet. What would the world look like with extra colors? That’s the question researchers want to answer with this system for duplicating different animals’ views of the world.
Of course, this would be easy if you were thinking about dogs or cats. They can’t see the difference between red and green, making them effectively colorblind by human standards. Researchers are using modified commercial cameras and sophisticated video processing to produce images that sense blue, green, red, and UV light. Then they modify the image based on knowledge of different animal photoreceptors.
We were somewhat surprised that the system didn’t pick up IR. As we know snakes, for example, can sense IR. You’d think more sophisticated animals would have better color vision, but that seems to be untrue. The mantis shrimp, for example, has 12-16 types of photoreceptors. Even male and female humans have different vision systems that make them see colors differently.
Just your typical backyard cleanroom shed. (Credit: Dr. Semiconductor, YouTube)
Most people see that garden shed as little more than a place to store some gardening tools in, but if you’re like [Dr. Semiconductor], then what you see is a potential cleanroom for semiconductor manufacturing. As ridiculous as this may sound, the basic steps behind the different levels of cleanrooms work just as well for a multi-million dollar fab as they do for for a basic shed.
Key to everything is HEPA filtration along with positive pressure, to constantly push clean air into the cleanroom, while preventing dirty air from flowing in. The shed was also split into two sections, the first room once you enter it being the the gowning room. This is where you change into cleanroom gear before you transition into the cleanroom.
In addition to the flame-resistant drywalls, a water-based epoxy coating was applied to the insides of the cleanroom walls to make it smooth and free of debris. The HEPA filtration system constantly filters the shed’s air along with some fresh outside air, while an airconditioning unit ensures that the temperature remains constant.
The measured >0.5 µm particle contamination inside the shed turned out to be enough for a FED STD 209E equivalent of Class 100, which is ISO 5 class with a maximum of 3,520 particles/m3. For comparison, room air is ISO 9 with max 35,200,000 particles/m3. At ISO 5 it’s good enough to do some semiconductor R&D laboratory things, which is what [Dr. Semiconductor]’s channel is – shockingly – about.
Elastocaloric materials are a class of materials that exhibit a big change in temperature when exposed to mechanical stress. This could potentially make them useful as solid-state replacement for both vapor-compression refrigeration systems and Peltier coolers.
The entire assembled elastocaloric device. (Credit: Guoan Zhou, Nature, 2026)
So far one issue has been that reaching freezing temperatures was impossible, but a recently demonstrated solution (online PDF via IEEE Spectrum) using NiTi-based shape-memory alloys addressed that issue with a final temperature of -12°C achieved within 15 minutes from room temperature.
In the paper by [Guoan Zhou] et al. the cascade cooler is described, with eight stages of each three tubular, thin-walled NiTi structures. Each of these stages is mechanically loaded by a ceramic head that provides the 900 MPa mechanical stress required to transfer thermal energy via the stages from one side to the other of the device, alternately absorbing or releasing the energy with CaCl2 as the heat-exchange fluid.
NiTi alloys are known as about the ideal type of SMA for this elastocaloric purpose, so how much further this technology can be pushed remains to be seen. For stationary refrigeration applications it might just be the ticket, but we’ll have to see as the technology is developed further.
Liquid nitrogen isn’t exactly an everyday material, but it’s acquired conveniently enough to be used in extreme overclocking experiments, classroom demonstrations, chemistry and physics experiments, and a number of other niche applications. Liquid oxygen, by contrast, is dangerous enough that it’s only really used in rocket engines. Nevertheless, [Electron Impressions] made some of his own, and beyond the obvious pyrotechnic experimentation, demonstrated its unusual magnetic properties. Check out the video, below.
The oxygen in this case was produced by electrolysis through a proton-exchange membrane, which vented the hydrogen into the atmosphere and routed the oxygen into a Dewar flask mounted at the cold end of a Stirling cryo-cooler. The cooler had enough power to produce about 30 to 40 milliliters of liquid oxygen per hour, enough to build up an appreciable amount in short order. As expected, the pale blue liquid caused burning paper to disappear in a violent flame, and a piece of paper soaked in it almost exploded when ignited.
Although not as reviled as the sound of nails on chalkboard, the sound of adhesive tape being peeled is quite probably at least as distinctive. With every millimeter of the tape’s removal from the roll sounding like it’s screaming in protest, it has led some to wonder just why this process is noisy enough to be heard from across an open-plan office. Recently [Er Qiang Li] et al. had their paper on a likely theory published in Physical Review E, in which they examine the supersonic air pulses at the core of this phenomenon.
The shockwaves produced by peeling tape, captured on Schlieren imaging. (Credit: Er Qiang Li et al., 2026)
Using rolls of adhesive tape and two microphones synchronized with two high-speed cameras in a Schlieren imaging setup, they gathered experimental data of this stick-slip mechanism. Incidentally, in addition to this auditory effect, adhesive tape is also known for the triboluminescence effect, as well as the generating of X-rays, making them quite the source of scientific demonstrations, even when they’re not also being used to create graphene with.
What they deduced from the recorded data was that the transverse fractures that suddenly appear after the extended stick phase hold a vacuum until they reach the end of the fracture during the brief slip phase, at which point the vacuum collapses very suddenly. This produces a pressure of 9600 Pa and clearly visible shock fronts on the Schlieren images.
Now that we know why peeling adhesive tape from its roll is so noisy, it won’t make it any more quiet, but at least we can add another fascinating science fact to its roll of achievements.
In science fiction, the use of gunpowder-based weapons is generally portrayed as something from a savage past, with technology having long since moved on to more civilized types of destructive weaponry, involving lasers, microwaves, and electromagnetism. Instead of messy detonating powder, energy-weapons are used to near-instantly deposit significant amounts of energy into the target, and railguns enable the delivery of projectiles at many times the speed of sound using nothing but the raw power of electricity and some creative physics.
Of course, the reason that we don’t see sci-fi weapons deployed everywhere has arguably less to do with today’s levels of savagery in geopolitics and more with the fact that physical reality is a very harsh mistress, who strongly frowns upon such flights of fancy.
Similarly, the Lorentz force that underlies railguns is extremely simple and effective, but scaled up to weapons-grade dimensions results in highly destructive forces that demolish the metal rails and other components of the railgun after only a few firings. Will we ever be able to fix these problems, or are railguns and similar sci-fi weapons forever beyond our grasp?
