Subject: Space-tech Digest #89 Contents: Bob Munck Re: Tubular Carbon Microfilaments John Roberts Re: Tubular Carbon Microfilaments Bob Munck Re: Tubular Carbon Microfilaments John Burger Discursus: Origin of ``buckyball'' Gordon Pusch Origin of Name "Buckyballs" Paul Dietz 3He at lunar poles? John Roberts Re: 3He at lunar poles? ------------------------------------------------------------ To: space-tech@cs.cmu.edu Subject: Re: Tubular Carbon Microfilaments Reply-To: munck@STARS.Reston.Unisys.COM Date: Mon, 25 Nov 91 17:22:32 -0500 From: Bob Munck >The most (?) recent issue of Nature {also Sci. Am.} (says) > Some Japanese scientists >have found that they can make short (~ 1 micron) carbon fibers that >consist of multiple concentric layers of graphite bent into tubes. >Kind of like the fullerenes, but very elongated. ... >These fibers, if they can be made longer, should be much stronger >than conventional graphite fibers. Interesting implications for >high strength composites and high tensile strength cables. I take a certain pride in having suggested something like this in this forum a month ago: "buckyball chains" henry@zoo said at the time that "*making* such a material is very non-trivial" which apparently turns out not to be the case; it sounds like it grows spontaneously under the right conditions. (I suppose that's actually true of just about everything.) What I want to know is what kind of strength we're talking about. If they can grow them to visible size, say millimeters, and the cost is on the order of that of the raw material, are we approaching the strength needed for an Earth beanstalk? Can we make a cable out of very strong filaments, given that they probably slide over each other with the kind of friction that graphite shows? What else would a super-strength cable make possible? Lofstrom Loops? My earth-circumfrance hula-hoop? Henry speculated that stiffness would be high; is that important? Bob Munck ------------------------------ Date: Mon, 25 Nov 91 22:07:42 EST From: John Roberts Disclaimer: Opinions expressed are those of the sender and do not reflect NIST policy or agreement. To: space-tech@cs.cmu.edu Subject: Re: Tubular Carbon Microfilaments >To: space-tech@cs.cmu.edu >Subject: Re: Tubular Carbon Microfilaments >Date: Mon, 25 Nov 91 17:22:32 -0500 >From: Bob Munck >>The most (?) recent issue of Nature {also Sci. Am.} (says) >> Some Japanese scientists >>have found that they can make short (~ 1 micron) carbon fibers that >>consist of multiple concentric layers of graphite bent into tubes. >>Kind of like the fullerenes, but very elongated. ... >>These fibers, if they can be made longer, should be much stronger >>than conventional graphite fibers. Interesting implications for >>high strength composites and high tensile strength cables. >I take a certain pride in having suggested something like this in this forum >a month ago: "buckyball chains" henry@zoo said at the time that "*making* >such a material is very non-trivial" which apparently turns out not to be >the case; it sounds like it grows spontaneously under the right conditions. >(I suppose that's actually true of just about everything.) It was about the same for buckminsterfullerine - proposed several years ago, it was only around this year that it was found to be easy to make. By the way, I strongly disapprove of the term "buckyball" - it totally loses the "point" of the original name. I believe the nickname was cooked up by a science fiction writer to make a story more "cute". (I don't remember the name of the story or the author, however.) John Roberts roberts@cmr.ncsl.nist.gov ------------------------------ To: space-tech@cs.cmu.edu Subject: Re: Tubular Carbon Microfilaments Reply-To: munck@STARS.Reston.Unisys.COM Return-Receipt-To: munck@Stars.Reston.Unisys.COM Date: Tue, 26 Nov 91 09:50:58 -0500 From: Bob Munck >By the way, I strongly disapprove of the term "buckyball" - it totally >loses the "point" of the original name. I talked with Bucky for a total of maybe six hours on several occasions (99.99% him talking, 0.01% me saying "Huh? How do you figure that?"). Based on this and the reading of all of his books, I believe that he would have approved of the term "buckyball" (and, if it comes to that, "buckyrod"). Bob Munck ------------------------------ Full-Name: John D. Burger Posted-Date: Tue, 26 Nov 91 10:04:52 EST To: space-tech@cs.cmu.edu Subject: Discursus: Origin of ``buckyball'' Date: Tue, 26 Nov 91 10:04:52 EST From: john@linus.mitre.org Re: By the way, I strongly disapprove of the term "buckyball" - it totally loses the "point" of the original name. I believe the nickname was cooked up by a science fiction writer to make a story more "cute". (I don't remember the name of the story or the author, however.) John Roberts roberts@cmr.ncsl.nist.gov How does the nickname ``lose the `point' ''? Everybody called Richard Buckminster Fuller ``Bucky'', and the basic fullerene does indeed have the shape of a ball. I'm pretty sure that some of the original researchers came up with the nickname, not a science fiction author. Fullerenes doped with non-carbon atoms are generically called ``dopyballs''. Richard Smalley (Rice University) uses ``sillyball'' to refer to buckyballs modified with silicon, while Fred Wahl (UC, Santa Cruz) calls another variety ``hairyballs''. (I think these are fullerenes with extra atoms sticking out, giving the appearance of cilia.) John Burger john@mitre.org ------------------------------ Date: Tue, 26 Nov 1991 10:28 EST From: "GORDON D. PUSCH" Subject: Origin of Name "Buckyballs" To: space-tech@cs.cmu.edu X-VMS-To: SPACE-TECH X-VMS-Cc: PUSCHG >By the way, I strongly disapprove of the term "buckyball" - it totally >loses the "point" of the original name. I believe the nickname was cooked >up by a science fiction writer to make a story more "cute". (I don't >remember the name of the story or the author, however.) > >John Roberts >roberts@cmr.ncsl.nist.gov The first time I remember reading the term "buckyball" *was* in an SF story by Charles Sheffield; don't remember story title but it was the very last story in his collection _The_McAndrew_Chronicles_ ... Gordon D. Pusch < puschg@crl.aecl.ca > ------------------------------ Date: Tue, 3 Dec 91 09:15:05 EST From: dietz@cs.rochester.edu To: space-tech@cs.cmu.edu Subject: 3He at lunar poles? The recent discussion of lunar polar volatiles and a related discussion of 3He in lunar regolith makes me wonder: could there be larger concentrations of 3He at the lunar poles? Of course, helium cannot condense there, but perhaps the rate of diffusion of implanted helium is much lower at reduced temperature. This might increase the equilibrium concentration of 3He in the regolith. Paul F. Dietz dietz@cs.rochester.edu ------------------------------ Date: Tue, 3 Dec 91 12:29:25 EST From: John Roberts Disclaimer: Opinions expressed are those of the sender and do not reflect NIST policy or agreement. To: space-tech@cs.cmu.edu Subject: Re: 3He at lunar poles? My understanding is that 3He comes from the solar wind. What is the proposed mechanism for its deposit on the lunar surface? Does it require high-speed impact to "stick"? Would the fact that the polar regions are shaded from sunlight also mean that they don't get as much of a deposit of 3He, or might interaction with Earth's magnetic field cause some to "swirl" around and be deposited there? Does 3He once deposited tend to stay there, or is there an equillibrium, such that if no further deposition occurs, what's there eventually evaporates? Finally, at what rate is it deposited? (I seem to recall reading that the moon's axis of rotation was once different from what it is now, but I don't remember whether that was a studied conclusion or a wild hypothesis.) Hm, just more questions. Not much help (unless somebody knows the answers). John Roberts roberts@cmr.ncsl.nist.gov ------------------------------ End of Space-tech Digest #89 *******************