Could graphene be the impetus for electromagnetic ...

2009-07-09T08:34:08.659-07:00

Could graphene be the impetus for electromagnetic propulsion and the actual electro-framework for an aviation device such as a so-called "flying saucer"?
DaveSalcido@gmail.com

Discussion of materials for shielding against ioni...

2008-08-04T12:18:00.000-07:00

Discussion of materials for shielding against ionizing radiation. The more hydrogen in the materials the better the radiation shielding.

Lithium hydride is a popular shield material for nuclear power reactors, but is generally not useful for other functions. The graphite nanofiber materials heavily impregnated with hydrogen or any composite thereof may well represent a viable multifunctional component in future space structures. In this case study of the graphite nanofiber, hydrogen content is ~ 68% wt while in laboratory in single-walled carbon nanotubes (SWNT) hydrogen storage has been achieved ~ 10% wt.

So hydrogen added to graphite and graphene would be good regular physical shielding material. Probably not that helpful for widespread use but for some hardened sites it could be affordable and helpful.

Revolutionary methods of radiation shielding

A discussion about how much magnetic and other electric fields are needed to stop radiation.

(1) Active (electromagnetic) shield concepts:
• Electric fields.
• Magnetic fields (attached coils).
• Magnetic fields (deployed large-diameter coils or shields bearing magnets).
• Plasma methods (expand magnetic field, produce electric field).
Common elements:
• Many previous studies of physics for most; some studies of engineering.
• Requires space power to develop fields; requires superconducting magnets.
• To shield against GCRs one must have either very high fields or very extended fields.
• ∫ L BXdl
> 1,000 G km or V > 10**10 V.
Proposed figures of merit/discriminators:
• ∫ L BXdl
> 1,000 G km or V > 10**10 V.
• Smallest stored energies in field.
• Minimized effects of fields on crew and equipment (<2,000 G).
• Perceived practicality.
• Hazards.

(3) Novel materials concepts:
• Quasi-crystal H absorbers.
• Palladium, alloys as H absorbers.
• Carbon nano-material absorbers.
• Solid H.
• Metal hydrides.
• Borated CH2 and other compounds.
Common elements:
• Mass shielding.
• Goal is lowest average atomic mass achievable (polyethylene, CH2 is current “standard”).
• Dual use would modify the lowest average atomic mass rule.
• Neutron absorption.
• Structural or other use.
• Volumetric considerations.
Proposed figures of merit/discriminators:
• Average atomic mass number.
• Mass fraction of H.
• Dual use as construction material, neutron absorber, fuel, etc.
• Perceived practicality (fabrication, mechanical properties).
• Hazards.

I wonder how successfully this substance can be ad...

2008-08-03T18:38:00.000-07:00

I wonder how successfully this substance can be added to polyethylene-based (plastic) structural siding and roofing materials? I would think the increased thermal insulation (and to a lessor extent electrical as well) achieved, along with the increased structural strength, would be considered a positive factor, even at some appreciable added cost over traditional materials.

In light of your recent post on radioactivity protection from structural design and materials Brian, any information as to graphene's radiocative shielding qualities?

Comments on Next Big Future: Graphene enhanced plastics

Could graphene be the impetus for electromagnetic ...

Discussion of materials for shielding against ioni...

I wonder how successfully this substance can be ad...