问答题Practice 3　　The shotgun marriage of chemistry and engineering called “Nanotechnology” is ushering in the era of serf-replicating machinery and serf-assembling consumer goods made from cheap raw atoms.　　Nanotechnology is molecular manufacturing or, more

Practice 3　　The shotgun marriage of chemistry and engineering called “Nanotechnology” is ushering in the era of serf-replicating machinery and serf-assembling consumer goods made from cheap raw atoms.　　Nanotechnology is molecular manufacturing or, more simply, building things one atom or molecule at a time with programmed baroscopic robot arms. A nanometer is one billionth of a meter (3-4 atoms wide).　　Utilizing the well understood chemical properties of atoms and molecules (how they “stick” together), nanotechnology proposes the construction of novel molecular devices possessing extraordinary properties. The trick is to manipulate atoms individually and place them exactly where needed to produce the desired structure. This ability is almost in our grasp. The anticipated payoff for mastering this technology is far beyond any human accomplishment so far.　　By treating atoms as discrete, bit-like objects, molecular manufacturing will bring a digital revolution to the production of material objects. Working at the resolution limit of matter, it will enable the ultimate in miniaturization and performance. By starting with cheap, abundant components-molecules-and processing them with small, high-frequency, high-productivity machines, it will make products inexpensive. Design computers that each executes more instructions per second than all of the semiconductor CPUs in the world combined.　　Nanotechnology will reverse the harm done by the industrial revolution. Imagine being able to cure cancer by drinking a medicine stirred into your favorite fruit juice. Imagine a supercomputer no bigger than a human cell Imagine a four-person, surface-to-orbit spacecraft no larger or more expensive than the family car. These are just a few products expected from nanotechnology.　　Humanity will be faced with a powerful, accelerated social revolution as a result of nanotechnology. In the near future, a team of scientists will succeed in constructing the first nano-sized robot capable of self-replication. Within a few short years, and five billion trillion nano-robots later, virtually all present industrial processes will be obsolete as well as our contemporary concept of labor. Consumer goods will become plentiful, inexpensive, smart, and durable. Medicine will take a quantum leap forward, space travel and colonization will become safe and affordable.　　For these and other reasons, global life styles will change radically and human behavior will be drastically impacted. The world is on the brink of a new technological revolution beyond any human experience. A new, more powerful industrial revolution capable of bringing wealth, health, and education, without pollution, to every person on the planet. No longer will forest need to be cut or smoke spewed into the air. This is the promise of nanotechnology.　　A nanometer is one billionth of a meter. That’s a thousand, million times smaller than a meter. If you blew up a baseball to the size of the earth, the atoms would become visible, about the size of grapes. Some 3-4 atoms fit lined up inside a nanometer.