The technology of historical themes is changing with each passing day.

Nanometer is a unit of measurement for geometric dimensions, and its length is only one billionth of a meter, which is slightly equal to the scale of 45 atoms. The diameter of a hair is 70,000 to 80,000 nanometers.

The technology of manipulating and processing atoms and molecules in this scale is called nanotechnology. The development of nanotechnology is to produce surgical tools that can treat diseases at the molecular level, computers smaller than human cells, and ultra-efficient micro-machine tools with anti-pollution ability.

Scientists drew a blueprint for us a few years later: ultra-light new materials may make space travel cheap and easy, and even use nanotechnology to create an atmosphere on Mars, as predicted by some writers. If the new "nano-medicine" can produce new cells molecule by molecule when cells age, thus prolonging people's life indefinitely, then it is necessary to emigrate to space. Nanotechnology has created enough small miracles to at least convince some scientific giants that these grand ideas will also come true.

Nano is a unit of length, originally called "nano", that is, 10-9(65438+ billionth of a meter). Nanoscience and technology, sometimes called nanotechnology, is to study the properties and applications of materials with structural dimensions ranging from 1 to 100 nm.

From the specific material, people often use "as thin as hair" to describe slender things. In fact, human hair is generally 20-50 microns in diameter, not thin. A single bacterium is invisible to the naked eye, and the diameter measured by a microscope is 5 microns, which is not too fine. At the extreme, 1 nm is roughly equivalent to the diameter of 4 atoms.

Nanotechnology includes the following four main aspects:

The first aspect is nanomaterials, including preparation and characterization. On the nanometer scale, the emission of electrons (quantum mechanical properties) and the interaction of atoms in matter will be affected by the size. If the nano-scale structure can be obtained, it is possible to control the basic properties of materials such as melting point, magnetism, capacitance and even color. Without changing the chemical composition of the substance. The hardness of ceramics sintered by ultrafine particles can be higher, but it does not crack: inorganic ultrafine particle ash will stick to the end points of polymer molecules after adding rubber, which greatly reduces the wear of tires and has a long service life.

The second aspect is nano-dynamics, mainly micro-machinery and micro-motors, or micro-electromechanical systems (MEMS), which are used as micro-sensors and actuators for transmission machinery, optical fiber communication systems, special electronic equipment, medical and diagnostic instruments, etc. MEMS uses a new technology similar to the design and manufacture of integrated devices. The feature is that the parts are very small, the etching depth often needs tens to hundreds of microns, and the width error is very small. This process can also be used to manufacture three-phase motors, ultra-high-speed centrifuges or gyroscopes. In the research, micro-deformation and micro-friction at quasi-atomic scale should be detected accordingly. Although they have not really entered the nanometer scale at present, they have great potential scientific and economic value.

The third aspect is nano-biology and nano-pharmacology, such as fixing DNA particles on mica surface with colloidal gold with nano-granularity, doing experiments on the interaction between biomolecules with interdigital electrodes on the surface of silicon dioxide, double-layer planar biofilm of phospholipids and fatty acids, and the fine structure of DNA. With nanotechnology, you can also put parts or components into cells through self-assembly to form new materials. About half of the new drugs, even the fine powder of micron particles, are insoluble in water; However, if the particles are nanoscale (i.e. ultrafine particles), they can be dissolved in water.

The fourth aspect is nano-electronics, including nano-electronic devices based on quantum effect, optical/electrical properties of nanostructures, characterization of nano-electronic materials, atomic manipulation and assembly. The current trend of electronic technology requires smaller, faster and colder equipment and systems. "Smaller" means faster response. "Cooler" means that a single device consumes less power. But "smaller" is not infinite.

Nanotechnology is the last frontier of builders, and its influence will be enormous.

1In April 1998, Dr. Neal Lane, the president's science and technology adviser, commented that if someone asked me which science and engineering field would have a breakthrough impact on the future, I would say that the start-up plan was to build a technology called nanotechnology. "Grand Challenge" sponsors interdisciplinary research and education teams, including centers and networks for long-term goals. Some potential breakthroughs include: compressing the data of the entire Library of Congress into a device the size of a cube of sugar, which is achieved by increasing the storage capacity per unit surface by 65,438+0,000 times, and expanding the storage capacity of large storage electronic devices to the level of several megabytes.

Materials and products are from small to large, that is, made up of an atom and a molecule. This method can save raw materials and reduce pollution.

Production strength is 10 times that of steel, and the weight is only a small part of steel, so as to make various lighter and more fuel-efficient land, water and air vehicles.

The speed and efficiency of computers have been improved by millions of times through tiny transistors and memory chips, and today's Pentium III processors have become very slow.

Using genes and drugs to deliver nano-scale MRI contrast agents to find cancer cells or locate human tissues and organs.

Remove the smallest pollutants in water and air to obtain a cleaner environment and drinkable water.

The energy efficiency of solar cells has been tripled.