proof that Raymond Damadian was a true visionary, one could find it
here.
Damadian even envisioned a truly advanced MRI machine
capable of not only detecting cancer, but of killing cancerous cells
outright. These machines would excite not hydrogen atoms, but
phosphorus atoms, common in cancer-damaged DNA. Damadian
speculated that certain Larmor frequencies in phosphorus might be
specific to cancerous tissue; if that were the case, then it might be
possible to pump enough energy into those phosphorus nuclei so that
they actually shivered loose from the cancer cell's DNA, destroying the
cancer cell's ability to function, and eventually killing it.
That's an amazing thought -- a science-fictional vision right out
of the Gernback Continuum. Step inside the booth -- drop a quarter --
and have your incipient cancer not only diagnosed, but painlessly
obliterated by invisible Magnetic Healing Rays.
Who the heck could believe a visionary scenario like that?
Some things are unbelievable until you see them with your own
eyes. Until the vision is sitting right there in front of you. Where it
can no longer be denied that they're possible.
A vision like the inside of your own brain, for instance.
SUPERGLUE
This is the Golden Age of Glue.
For thousands of years, humanity got by with natural glues like
pitch, resin, wax, and blood; products of hoof and hide and treesap
and tar. But during the past century, and especially during the past
thirty years, there has been a silent revolution in adhesion.
This stealthy yet steady technological improvement has been
difficult to fully comprehend, for glue is a humble stuff, and the
better it works, the harder it is to notice. Nevertheless, much of the
basic character of our everyday environment is now due to advanced
adhesion chemistry.
Many popular artifacts from the pre-glue epoch look clunky
and almost Victorian today. These creations relied on bolts, nuts,
rivets, pins, staples, nails, screws, stitches, straps, bevels, knobs, and
bent flaps of tin. No more. The popular demand for consumer
objects ever lighter, smaller, cheaper, faster and sleeker has led to
great changes in the design of everyday things.
Glue determines much of the difference between our
grandparent's shoes, with their sturdy leather soles, elaborate
stitching, and cobbler's nails, and the eerie-looking modern jogging-
shoe with its laminated plastic soles, fabric uppers and sleek foam
inlays. Glue also makes much of the difference between the big
family radio cabinet of the 1940s and the sleek black hand-sized
clamshell of a modern Sony Walkman.
Glue holds this very magazine together. And if you happen to
be reading this article off a computer (as you well may), then you
are even more indebted to glue; modern microelectronic assembly
would be impossible without it.
Glue dominates the modern packaging industry. Glue also has
a strong presence in automobiles, aerospace, electronics, dentistry,
medicine, and household appliances of all kinds. Glue infiltrates
grocery bags, envelopes, books, magazines, labels, paper cups, and
cardboard boxes; there are five different kinds of glue in a common
filtered cigarette. Glue lurks invisibly in the structure of our
shelters, in ceramic tiling, carpets, counter tops, gutters, wall siding,
ceiling panels and floor linoleum. It's in furniture, cooking utensils,
and cosmetics. This galaxy of applications doesn't even count the
vast modern spooling mileage of adhesive tapes: package tape,
industrial tape, surgical tape, masking tape, electrical tape, duct tape,
plumbing tape, and much, much more.
Glue is a major industrial industry and has been growing at
twice the rate of GNP for many years, as adhesives leak and stick
into areas formerly dominated by other fasteners. Glues also create
new markets all their own, such as Post-it Notes (first premiered in
April 1980, and now omnipresent in over 350 varieties).
The global glue industry is estimated to produce about twelve
billion pounds of adhesives every year. Adhesion is a $13 billion
market in which every major national economy has a stake. The
adhesives industry has its own specialty magazines, such as
Adhesives Age andSAMPE Journal; its own trade groups, like the
Adhesives Manufacturers Association, The Adhesion Society, and the
Adhesives and Sealant Council; and its own seminars, workshops and
technical conferences. Adhesives corporations like 3M, National
Starch, Eastman Kodak, Sumitomo, and Henkel are among the world's
most potent technical industries.
Given all this, it's amazing how little is definitively known
about how glue actually works -- the actual science of adhesion.
There are quite good industrial rules-of-thumb for creating glues;
industrial technicians can now combine all kinds of arcane
ingredients to design glues with well-defined specifications:
qualities such as shear strength, green strength, tack, electrical
conductivity, transparency, and impact resistance. But when it
comes to actually describing why glue is sticky, it's a different
matter, and a far from simple one.
A good glue has low surface tension; it spreads rapidly and
thoroughly, so that it will wet the entire surface of the substrate.
Good wetting is a key to strong adhesive bonds; bad wetting leads
to problems like "starved joints," and crannies full of trapped air,
moisture, or other atmospheric contaminants, which can weaken the
bond.
But it is not enough just to wet a surface thoroughly; if that
were the case, then water would be a glue. Liquid glue changes
form; it cures, creating a solid interface between surfaces that
becomes a permanent bond.
The exact nature of that bond is pretty much anybody's guess.
There are no less than four major physico-chemical theories about
what makes things stick: mechanical theory, adsorption theory,
electrostatic theory and diffusion theory. Perhaps molecular strands
of glue become physically tangled and hooked around irregularities
in the surface, seeping into microscopic pores and cracks. Or, glue
molecules may be attracted by covalent bonds, or acid-base
interactions, or exotic van der Waals forces and London dispersion
forces, which have to do with arcane dipolar resonances between
magnetically imbalanced molecules. Diffusion theorists favor the
idea that glue actually blends into the top few hundred molecules of
the contact surface.
Different glues and different substrates have very different
chemical constituents. It's likely that all of these processes may have
something to do with the nature of what we call "stickiness" -- that
everybody's right, only in different ways and under different
circumstances.
In 1989 the National Science Foundation formally established
the Center for Polymeric Adhesives and Composites. This Center's
charter is to establish "a coherent philosophy and systematic
methodology for the creation of new and advanced polymeric
adhesives" -- in other words, to bring genuine detailed scientific
understanding to a process hitherto dominated by industrial rules of
thumb. The Center has been inventing new adhesion test methods
involving vacuum ovens, interferometers, and infrared microscopes,
and is establishing computer models of the adhesion process. The
Center's corporate sponsors -- Amoco, Boeing, DuPont, Exxon,
Hoechst Celanese, IBM, Monsanto, Philips, and Shell, to name a few of