Piezomechanochemistry backpressure pane

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This article is a stub. It needs to be expanded.

In mechanosynthesis cores and Chemomechanical converter cores
there is the need to provide sufficient counter-forces
for advanced piezomechanochemistry to be possible.

Negative back-pressure

Note that required back-pressure can often be negative too.
While VdW forces can support these too, stiffness may be lower.
So it might be desirable to provide back-pressure from the sides such
that compression and tension both face the same stiffness.

Friction losses

Disclaimer:
Note that minimizing friction losses is only sensible
if losses in piezomechanochemistry can be made so small
that they no longer massively dominate. This may or many not be possible.
(TODO: Investigate how far efficiency in piezomechanochemistry can be driven. This was not done in Nanosystems beyond very very crude levels.)

Options:
To minimize friction losses from sliding over back-pressure panes
there seem to be two options:

  • reduce the contact area
  • reduce contact time

Reduce contact area

As a crude first approximation: Half contact area gives half dynamic nanoscale friction.
There are limits to this though.
Fist stiffness falls potentially degrading efficiency in piezomechanochemistry
potentially causing much bigger losses than gained by less contact area.
Second for very small contact areas the atomic waviness may not average out well increasing losses again.
See: Friction in gem-gum technology

Reduce contact time

The idea is to bring the back-pressure pane only in contact with the workpiece holding attachment chain when needed.
So there is intermittent contact. If the attachment chain is not moving during contact then there is no sliding at all.
Well, except in the mechanism that periodically establishes and removes contact.
Also the chain needs to do periodic full stops.
Or the backpressure-panes match speed with the chain and reciprocate. Complicated.

Of peculiar concern may be that establishing and removing contact when done naively
leads to energy turnover as VdW bonds are established and removed.
Losses from this must be smaller than gains from the avoidance of sliding.
Otherwise there's no point.
One option for a less naive design may be VdW contactswap energyreplacement

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