Pure hydrogen in a balloon produces a low, loud, very satisfying bang. Completely different from a sound of an air balloon popping. Here is a video from a very good Royal Society of Chemistry demonstration series on various unusual combustion process:
Hydrogen mixed with air or with oxygen produces an ear piercing supersonic detonation, exceedingly loud and unpleasant. Not recommended for demonstrations.
There are many cases in the news of accidents with sometimes a large number of party balloons filled with hydrogen or other flammable gases.
One of the larger episodes was in 2012 in Armenia, where thousands of balloons exploded during a meeting, injuring 154 people, of which 4 seriously (the video is of poor quality): https://www.youtube.com/watch?v=jWEm2sS7Dw8
a party balloon - say a cubic foot - is about 2g of hydrogen. Involves 16g of oxygen. So we're talking 18g of very fast burning, borderline detonating mass. Releases 240 KJ of energy.
To compare the hand grenade - 60g TNT https://en.wikipedia.org/wiki/F-1_grenade_(Russia) - releases the same 240 KJ of energy.
Starlink project began after Musk and Greg Wyler parted their ways. Wyler approached SpaceX in 2014 with a proposal to build OneWeb (then called WorldVu), and initially they worked on the project together. But then they started to accuse each other of doing various underhanded things, and split. After that, Musk decided that he could do a similar and even better system without Wyler, and that's how Starlink was born in 2015.
Heat capacity is irrelevant -- argon and helium have exactly the same heat capacity per liter of gas, which would be the figure of merit in this context.
Heat conductivity, on the other hand, is an order of magnitude higher for helium, compared to argon, because its atoms are moving faster due to their lower mass.
When the gas is used for cooling, heat conductivity is important because it determines the conductivity through the boundary layer near surface, where the velocity of the flow drops to zero at the surface itself, and all the heat transport is through conduction rather than advection.
Sure. Line scan indoor units are extremely affordable, and some cost less that $20, sold as spare parts for robot vacuum cleaners. Outdoor units (with higher ambient light tolerance and longer range) are an order of magnitude more expensive, but also available.
The efficiency of X-ray tubes is proportional to voltage, and is about 1% at 100kV voltage. This is the ballpark for the garden variety Xray machines. But the wavelength of interest for lithography corresponds to the voltage of only about 100V, so the efficiency would be 10 parts per million.
The source in the ASML machine produces something like 300-500W of light. With an Xray tube this would then require an electron beam with 50 MW of power. When focused into a microscopic dot on the target this would not work for any duration of time. Even if it did, the cooling and getting rid of unwanted wavelengths would have been very difficult.
A light bulb does not work because it is not hot enough. I suppose some kind of RF driven plasma could be hot enough, but considering that the source needs to be microscopic in size for focusing reasons, it is not clear how one could focus the RF energy on it without also ruining the hardware.
So, they use a microscopic plasma discharge which is heated by the focused laser. It "only" requires a few hundred kilowatts of electricity to power and cool the source itself.
Neato from San Diego has developed a $30 (indoor, parallax based) LIDAR about 20 years ago, for their vacuum cleaners [1].
Later, improved units based on the same principle became ubiquitous in Chinese robot vacuums [2]. Such LIDARs, and similarly looking more conventional time-of-flight units are sold for anywhere between $20-$200, depending on the details of the design.
LSI Logic and VLSI Systems used to do such things in 1980s -- they produced a quantity of "universal" base chips, and then relatively inexpensively and quickly customized them for different uses and customers, by adding a few interconnect layers on top. Like hardwired FPGAs. Such semi-custom ASICs were much less expensive than full custom designs, and one could order them in relatively small lots.
Taalas of course builds base chips that are already closely tailored for a particular type of models. They aim to generate the final chips with the model weights baked into ROMs in two months after the weights become available. They hope that the hardware will be profitable for at least some customers, even if the model is only good enough for a year. Assuming they do get superior speed and energy efficiency, this may be a good idea.
The document referenced in the blog does not say anything about the single transistor multiply.
However, [1] provides the following description: "Taalas’ density is also helped by an innovation which stores a 4-bit model parameter and does multiplication on a single transistor, Bajic said (he declined to give further details but confirmed that compute is still fully digital)."
It'll be different gates on the transistor for the different bits, and you power only one set depending on which bit of the result you wish to calculate.
Some would call it a multi-gate transistor, whilst others would call it multiple transistors in a row...
That, or a resistor ladder with 4 bit branches connected to a single gate, possibly with a capacitor in between, representing the binary state as an analogue voltage, i.e. an analogue-binary computer. If it works for flash memory it could work for this application as well.
https://www.youtube.com/watch?v=Rwbyl7ywfhk&list=PLLnAFJxOjz...
Hydrogen mixed with air or with oxygen produces an ear piercing supersonic detonation, exceedingly loud and unpleasant. Not recommended for demonstrations.
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