2008-03-27

Space fuel

Fenn laughs at the concept of biofuels for spacecraft. Suggests hydrogen or or a mass driver or ion rocket.

Graphene Synthesis, Lithography

Bryan links to his notes on graphene Mentions graphene and eletron beam lithography = win because it can produce microprocessors

Fenn asks: How do you make semiconductors out of graphene? In an electron microscope, the e-beam starts out with a hot tungsten disc - that's the 'image'

Fenn: you'd have to make a mask that blocks electrons while they are still relatively

Bryan: Another method is to use a Scanning Tunneling Microscope. Apply voltage from the tip of the STM tip. Use a $100 STM project, apply a voltage to a sheet of graphene with some sort of photoresist or etchant over it. Process is slow, but Harvard is using it - not with graphene, but as a process in general. This process is slow but suitable.

Bryan mentions his notes on Graphene which contain links to buy the necessary chemicals from Sigma-Aldrich. Getting the process up to 1000 Celsius will be hard and will require a chamber.

Operations

Fenn wants a copy of the wiki db. Bryan can't provide it in time because his website is going down.

Bryan is upset that his dad is pulling his server down because of his fights with his brother.

Autogenix, SKDB

Fenn links to an item on pastebin that demonstrates what a specific formatting called Autogenix would look like. He's designing it.

Bryan is confused about what Autogenix is supposed to be. To him, it looks like a system to specify dependencies for self-replication rather than a simple package fromat for materials and tools for SKDB. At one point, Fenn refers to materials. Bryan thinks it would make more sense to refer to other packages.

Fenn responds by thinking that materials disappear over time. Bryan agrees. This strengthens his argument to refer to packages rather than specify exact materials. They come to agreement that 'a material is a specification, unless it's natural'.

Bryan wants to grab material specifications from materials science journals. A formal and respected source could attact 'some data monkeys or something'. Alternatively, just funding could allow a database to be built by workers.

Fenn thinks a database of materials should be built with a 'wiki approach' using ye or nay votes. The group would come to a consensus about how acceptable the material defintions are. Either way, the work can be sourced.

Bryan suggests that they design measuring machinery. He links to his instrumentation page, which is down at the time. Bryan notes that he doesn't have schematics yet.

Making the file format extendable or scriptable is discussed. The idea being that it would be possible to import libraries for different packages and the general concept of Autogenix/SKDB should actually be computational modelling, since different materials behave differently.

Fenn comments that there's a lot of stick-slip in normal threads which creates uncertainty for measurement. He doesn't know how to apply a large amount of force cheaply and repeatably. This is an example of why he believes the wiki-style approach to autogenix/skdb is the better one.

Bryan's counterargument is that he's not sure how materials would be assembled. The wiki would not allow a simple running of tests. Fenn rebuts by saying it would be a matter of checking computer models to actual measurements to see if they agree.