What is nanotechnology? 1. What is nanotechnology?

Nanoscience and technology is to study the movement and changes of atoms, molecules and other types of substances in the range of one millionth of a meter (10-8) to one millionth of a meter (10-9). At the same time, manipulating and processing atoms and molecules in this scale range is also called nanotechnology.

Atoms are arranged one by one into Chinese characters with the tips of scanning tunneling microscope, and the size of Chinese characters is only a few nanometers.

What is nano? Nanometer is the measurement unit of size or dimension: kilometer (103 )→ meter → centimeter → millimeter → micron → nanometer (10-9), which is four times the atomic size and one tenth of the thickness of hair.

Biotechnology, information technology and nanotechnology are the mainstream of scientific and technological development in the next century. Biotechnology's understanding of genes has produced transgenic biotechnology, which can treat stubborn diseases and create creatures that do not exist in nature. Information technology enables people to know world events at home, and the Internet can almost change people's lifestyle.

Nanoscience is to study the movement and changes of atoms, molecules and other types of substances in the range from one millionth of a meter (10-8) to one millionth of a meter (10-9). At the same time, manipulating and processing atoms and molecules in this scale range is also called nanotechnology.

Reductionism: Simplify the motion of matter to the level of atoms and molecules. Both atomism and quantum mechanics have achieved great success. Organic synthesis; Molecular biology; Genetically modified food, cloned sheep; Atomic spectrum and laser; Solid-state electronic theory and integrated circuits; Geometrical optics to optical fiber communication. The great achievements of classical physics, chemistry and mechanics in the macro world: computers and networks, spaceships, airplanes, automobiles and robots have changed people's lifestyles.

There are blind spots in science and technology, or there are cracks in the construction of human knowledge. One side of the crack is the micro-world with atoms and molecules as the main body, and the other side is the macro-world of human activities. There is no direct and simple connection between the two worlds, and there is a transitional zone-the nano-world.

Example: molecular synthesis ≤ 1.5nm → living microelectronic technology 0.2μm, and microsurgery can only connect large, small and microvessels ≤ PM 10 and PM 1.5 particles. In 1950s, Qian Lao's "Physical Mechanics" was one of the pioneering works trying to connect two worlds.

When ten atoms or molecules or thousands of atoms or molecules are "combined" together, they show properties different from those of a single atom or molecule and a large object. This "combination" is called "supramolecule" or "artificial molecule". The melting point, magnetism, capacitance, conductivity, luminescent dyeing, color and water solubility of supramolecules have all changed greatly. When "supramolecules" continue to grow up, or gather into large pieces of matter in the usual way, they will lose strange properties, such as children who don't grow up.

At the scale of 10nm, the understanding of new laws in the system composed of a few electrons, atoms or molecules and how to manipulate or combine them, detect and apply them are the main problems of nanotechnology.

Materials and preparation: lighter, stronger and designable; Long service life and low maintenance cost; Constructing materials with specific properties or materials that do not exist in nature at the nanometer level with new principles and new structures; Biological materials and bionic materials; Diagnosis and repair of nanometer damage in the process of material failure; Microelectronics and Computer Technology: Chip with 100nm line realized in 20 10 years. The goal of nanotechnology is: the microprocessor with nano-structure will improve its efficiency by one million times; 10 times the bandwidth of high frequency network system; Megabit memory (increased by 1000 times); Integrated nano-sensor system;

Rapid and efficient genome sequencing, gene diagnosis and gene therapy technology; New medication methods and drug' missile' technology; Durable and human-friendly artificial tissues and organs; Devices to restore vision and intelligence; Nanosensor system for early diagnosis of diseases. Computers with low energy consumption, radiation resistance and high performance; Nano-test, control and electronic equipment for micro spacecraft; Nanostructured coating materials have thermal barrier resistance and wear resistance.

Develop green energy and environmental treatment technology, reduce pollution and restore the damaged environment; Nano-porous material with pore size of 65438±0nm is used as the carrier of the catalyst; MCM-4 1 ordered nanoporous material (pore size 10- 100nm) is used to remove dirt; Nanoparticles modified polymer materials. On the nanometer scale, protein, ribose, nucleic acid, etc. Everything with biological activity is prepared according to the predetermined size, symmetry and arrangement. Implanting biomaterials into nano-materials and devices produces comprehensive properties with biological functions and other functions. Biomimetic chemicals and biodegradable materials, gene improvement and treatment of animals and plants, gene chips for DNA determination, etc.

2. What is nanotechnology

Nanotechnology The basic concept of arranging xenon atoms in IBM nanotechnology, sometimes called nanotechnology, is to study the properties and applications of materials with structural dimensions ranging from 0. 1 to 100 nm.

After the invention of 198 1 year scanning tunneling microscope, a molecular world with a length of 0. 1 to 100 nm was born, and its ultimate goal is to construct products with specific functions directly from atoms or molecules. Therefore, nanotechnology is actually a technology that uses single atoms and molecules to arrange substances.

Nanotechnology is a comprehensive subject with strong cross-cutting, and its research content involves the vast field of modern science and technology. Nano-science and technology mainly includes nano-system physics, nano-chemistry, nano-materials, nano-biology, nano-electronics, nano-processing, nano-mechanics and so on.

These seven relatively independent and interpenetrating disciplines and three research fields: nano-materials, nano-devices and nano-scale detection and characterization. The preparation and research of nano-materials are the basis of the whole nano-technology.

Among them, nano-physics and nano-chemistry are the theoretical basis of nano-technology, and nano-electronics is the most important content of nano-technology. From the current research, there are three concepts about nanotechnology: the first is the molecular nanotechnology put forward by American scientist Dr. drexler in the book "The Machine of Creation" in 1986.

According to this concept, we can make the machine of combining molecules practical, so that we can combine various molecules at will and make any molecular structure. The nanotechnology of this concept has not made significant progress.

The second concept defines nanotechnology as the limit of micromachining technology. That is, the technology of artificially forming nano-scale structures through nano-precision "processing".

This nano-scale processing technology also makes the miniaturization of semiconductors reach the limit. Even if the existing technology continues to develop, it will eventually reach the limit in theory, because if the line width of the circuit is gradually reduced, the insulation film forming the circuit will become extremely thin, destroying the insulation effect.

In addition, there are problems such as fever and trembling. In order to solve these problems, researchers are studying new nanotechnology.

The third concept is put forward from a biological point of view. It turns out that organisms have nano-scale structures in cells and biomembranes.

The development of DNA molecular computer and cell biological computer has become an important part of nanotechnology. Overview of Nanotechnology -technology 1993 The first International Nanotechnology Conference (INTC) was held in the United States, which divided nanotechnology into six branches: nanophysics, nanobiology, nanochemistry, nanoelectronics, nanoprocessing technology and nanometrology, which promoted the development of nanotechnology.

Because of its particularity, magic and universality, this technology has attracted many outstanding scientists from all over the world to work hard for it. Nanotechnology generally refers to nano-scale (0. 1- 100nm) materials, design, manufacture, measurement, control and product technology.

Nanotechnology mainly includes: nanoscale measurement technology: nanoscale surface physical and mechanical properties detection technology: nanoscale processing technology; Preparation technology of nanoparticles; Nanomaterials; Nanobiotechnology; Nanoassembly technology, etc. Nanotechnology-the development history Nanotechnology was inspired by a speech entitled "There is still a lot of room at the bottom" published by the late physicist richard feynman1959.

The professor who teaches at California Institute of Technology put forward a new idea to his colleagues. Since the Stone Age, all human technologies, from sharpening arrows to photoetching chips, have been related to cutting or fusing hundreds of millions of atoms at one time in order to make substances into useful forms.

Fan Man asked, why can't we assemble from a single molecule or even an atom from another angle to meet our requirements? He said: "At least in my opinion, the laws of physics do not rule out the possibility of making things atom by atom." Richard feynman 1990, scientists from almaden Research Center of IBM successfully rearranged single atoms, and a key breakthrough was made in nanotechnology.

They used a device called scanning probe to slowly move 35 atoms to their respective positions, forming three letters of IBM. This proves that Feynman is right. These two letters add up to less than 3 nanometers long.

Soon, scientists can not only manipulate individual atoms, but also "spray atoms". Using molecular beam epitaxy, scientists have learned how to make extremely thin special crystal films, and only one layer of molecules can be made at a time.

At present, this technology is used to manufacture computer hard disk read-write heads. Richard feynman, a famous physicist and Nobel Prize winner, predicted that human beings can make smaller machines with small machines, and eventually they will arrange atoms one by one according to human wishes to make products. This is the earliest dream about nanotechnology. In 1970s, scientists began to put forward ideas about nanotechnology from different angles. 1974, scientist Donnie Gucci first used the term nanotechnology to describe precision machining. 1982, scientists invented the scanning tunneling microscope, an important tool for studying nanotechnology, which revealed a visible atomic and molecular world for us and played a positive role in promoting the development of nanotechnology. 1990 in July, the first international nanotechnology conference was held in Baltimore, USA, marking the official birth of nanotechnology. 199 1 year, carbon nanotubes were discovered by humans. Their mass is one sixth of that of steel with the same volume, but their strength is 10 times that of steel, which has become the focus of nanotechnology research. Professor smalley, winner of the Nobel Prize in Chemistry, believes that carbon nanotubes will be the first choice for the best fibers in the future, and will also be widely used in ultramicro wires, ultramicro switches and nanoelectronic circuits. 1993, following 1989, when Stanford University moved the atomic group to "write" Stanford University's English, and 1990, when IBM expelled "IBM" from the nickel surface with 36 xenon atoms, the Beijing Vacuum Physics Laboratory of Chinese Academy of Sciences manipulated the atoms freely and successfully wrote the word "China", which marked the beginning of China's international nanotechnology field. 1997, American scientists successfully used single electrons to move single electrons for the first time. It is predicted that after 20 years, a quantum computer with thousands of times higher speed and storage capacity will be developed.

3. What is nanotechnology

Nanotechnology is a kind of science and technology that uses a single atom and molecule to make substances. It studies the properties and applications of materials with structural dimensions ranging from 1 to 100 nm.

Nanotechnology is based on many modern advanced science and technology, including dynamics science and modern science (chaotic physics, intelligent quantum, quantum mechanics, mesoscopic physics, molecular biology).

Modern technology (computer technology, microelectronics and scanning tunneling microscope technology, nuclear analysis technology) and nanotechnology will trigger a series of new science and technology, such as nano-physics, nano-biology, nano-chemistry, nano-electronics, nano-processing technology and nano-metrology.

Extended data:

1, nanometer is the unit of measurement for geometric dimensions, 1 nanometer = one millionth of a millimeter.

2. Nanotechnology has promoted the technological revolution.

3. Drugs made by nanotechnology can block capillaries and "starve" cancer cells.

4. If nano-integrated devices are used on the satellite, the satellite will be smaller and easier to launch.

Nanotechnology is a synthesis of many sciences, and some goals take a long time to achieve.

6. Nanotechnology, information science and technology and life science and technology are the mainstream of current scientific development, and their development will make human society, living environment and science and technology itself better.

7. Nanotechnology can observe the pathological changes and conditions of cancer cells in patients, so that doctors can prescribe the right medicine.

References:

Baidu encyclopedia-nanotechnology

4. What is nano?

For some time, nanotechnology has appeared frequently in the media, and the advantages of nanotechnology, nanomaterials and products manufactured by nanotechnology have also been widely publicized.

So, what is nanotechnology? This paper introduces this knowledge for beginners' reference. . Nanometer is the unit of length, and the symbol is nm.

1nm =1nm = 10 m (billionth of a meter), which is about the length of10 atoms. Suppose that a hair has a diameter of 0.05 mm and is divided into 50,000 hairs on average in the radial direction, and the thickness of each hair is about 1nm.

. 1, the significance of nanotechnology. The so-called nanotechnology refers to a brand-new technology to study the motion laws and characteristics of electrons, atoms and molecules in the scale of 0. 1~ 100 nanometers. In the process of studying the composition of matter, scientists found that several or dozens of countable atoms or molecules isolated on the nanometer scale show many new characteristics, and the technology of manufacturing equipment with specific functions by using these characteristics is called nanotechnology.

The main differences between nanotechnology and microelectronics are: nanotechnology studies the realization of specific functions of equipment by controlling single atoms and molecules, and it works by using the fluctuation of electrons; Microelectronics technology mainly realizes its function by controlling the population of electrons and works by using the particle nature of electrons. The purpose of people's research and development of nanotechnology is to achieve effective control of the entire micro-world.

Nanotechnology is a comprehensive subject with strong cross-cutting, and its research content involves the vast field of modern science and technology. From 65438 to 0993, the International Steering Committee of Nanotechnology divided nanotechnology into six sub-disciplines: nanoelectronics, nanophysics, nanochemistry, nanobiology, nanofabrication and nanometrology.

Among them, nano-physics and nano-chemistry are the theoretical basis of nano-technology, and nano-electronics is the most important content of nano-technology. . 2. Characteristics of nano-electronic devices. The performance of electronic devices manufactured by nanotechnology is much better than that of traditional electronic devices. The working speed of nano-electronic devices is 65,438+0,000 times that of silicon devices, so the product performance can be greatly improved.

Low power consumption, the power consumption of nano-electronic devices is only11000 of that of silicon devices. There is a lot of information storage. A 5-inch CD less than the palm of your hand can store all the books of at least 30 Beijing libraries.

Small size and light weight can greatly reduce the size and weight of various electronic products. For some time, nanotechnology has appeared frequently in the media, and the advantages of nanotechnology, nanomaterials and products manufactured by nanotechnology have also been widely publicized.

So, what is nanotechnology? This paper introduces this knowledge for beginners' reference. . Nanometer is the unit of length, and the symbol is nm.

1nm =1nm = 10 m (billionth of a meter), which is about the length of10 atoms. Suppose that a hair has a diameter of 0.05 mm and is divided into 50,000 hairs on average in the radial direction, and the thickness of each hair is about 1nm.

. 1, the significance of nanotechnology. The so-called nanotechnology refers to a brand-new technology to study the motion laws and characteristics of electrons, atoms and molecules in the scale of 0. 1~ 100 nanometers. In the process of studying the composition of matter, scientists found that several or dozens of countable atoms or molecules isolated on the nanometer scale show many new characteristics, and the technology of manufacturing equipment with specific functions by using these characteristics is called nanotechnology.

The main differences between nanotechnology and microelectronics are: nanotechnology studies the realization of specific functions of equipment by controlling single atoms and molecules, and it works by using the fluctuation of electrons; Microelectronics technology mainly realizes its function by controlling the population of electrons and works by using the particle nature of electrons. The purpose of people's research and development of nanotechnology is to achieve effective control of the entire micro-world.

Nanotechnology is a comprehensive subject with strong cross-cutting, and its research content involves the vast field of modern science and technology. From 65438 to 0993, the International Steering Committee of Nanotechnology divided nanotechnology into six sub-disciplines: nanoelectronics, nanophysics, nanochemistry, nanobiology, nanofabrication and nanometrology.

Among them, nano-physics and nano-chemistry are the theoretical basis of nano-technology, and nano-electronics is the most important content of nano-technology. . 2. Characteristics of nano-electronic devices. The performance of electronic devices manufactured by nanotechnology is much better than that of traditional electronic devices. The working speed of nano-electronic devices is 65,438+0,000 times that of silicon devices, so the product performance can be greatly improved.

Low power consumption, the power consumption of nano-electronic devices is only11000 of that of silicon devices. There is a lot of information storage. A 5-inch CD less than the palm of your hand can store all the books of at least 30 Beijing libraries.

Small size and light weight can greatly reduce the size and weight of various electronic products.

5. What is nanotechnology

Nanotechnology, also known as nanotechnology, is a technology to study the properties and applications of materials with structural dimensions ranging from 1 nm to 100 nm.

After the invention of 198 1 year scanning tunneling microscope, a molecular world with the length of 1 to 100 nm was born, and its ultimate goal was to construct products with specific functions directly from atoms or molecules. Therefore, nanotechnology is actually a technology of making substances with single atoms and molecules.

From the current research, there are three concepts about nanotechnology:

1 yes 1986 American scientist Dr. drexler put forward a molecular nanotechnology in his book The Machine of Creation. According to this concept, we can make the machine of combining molecules practical, so that we can combine various molecules at will and make any molecular structure. The nanotechnology of this concept has not made significant progress.

2. Nanotechnology is positioned as the limit of micromachining technology. That is, the technology of artificially forming nano-scale structures through nano-precision "processing". This nano-scale processing technology also makes the miniaturization of semiconductors reach the limit.

Even if the existing technology continues to develop, it will eventually reach the limit in theory, because if the line width of the circuit is gradually reduced, the insulation film forming the circuit will become extremely thin, destroying the insulation effect. In addition, there are problems such as fever and trembling. In order to solve these problems, researchers are studying new nanotechnology.

3. From a biological point of view. It turns out that organisms have nano-scale structures in cells and biomembranes. The development of DNA molecular computer and cell biological computer has become an important part of nanotechnology.

Extended data:

Application field:

At present, the research and application of nanotechnology are mainly in the fields of materials and preparation, microelectronics and computer technology, medicine and health, aerospace and aviation, environment and energy, biotechnology and agricultural products. The equipment made of nano-materials has lighter weight, stronger hardness, longer service life, lower maintenance cost and more convenient design.

Nano-materials can also be used to make materials with specific properties or materials that do not exist in nature, and to make biological materials and bionic materials.

1, nanometer is the unit of measurement for geometric dimensions, 1 nanometer = one millionth of a millimeter.

2. Nanotechnology has promoted the technological revolution.

3. Drugs made by nanotechnology can block capillaries and "starve" cancer cells.

4. If nano-integrated devices are used on the satellite, the satellite will be smaller and easier to launch.

Nanotechnology is a synthesis of many sciences, and some goals take a long time to achieve.

6. Nanotechnology, information science and technology and life science and technology are the mainstream of current scientific development, and their development will make human society, living environment and science and technology itself better.

7. Nanotechnology can observe the pathological changes and conditions of cancer cells in patients, so that doctors can prescribe the right medicine.

Extended data:

Baidu encyclopedia-nanotechnology

6. What is nanotechnology?

"Nano-materials" and "nano-technology" are terms that often appear in science and technology newspapers in 1990s. What is "nanomaterial"? In layman's terms, it is a substance composed of tiny particles with a size of only a few nanometers. 1 nanometer is 1 billionth of a meter, which is invisible to the naked eye. However, materials made of nanoparticles have many special properties. Therefore, scientists also call it "ultrafine particle" material and "new material of 2 1 century". Nanomaterials didn't appear recently. The most primitive nano-materials appeared in China in12nd century BC, that is, Four Treasures of the Study-Mexico in China, and its important component was smoke. In fact, smoke is formed by many ultra-fine carbon blacks, and the process of making smoke and ink includes so-called nanotechnology.

1984, Gleiter, a German scientist, used a special method to press some extremely fine invisible metal powder into a small metal block, and studied the internal structure and properties of this small metal block in detail. It turns out that this metal has many incredible and specific metal properties and internal structures. The particularity of this material he made is that the general physical concept holds that the ordered arrangement of crystals is the main body of matter, and the defects and impurities in it are secondary and should be removed as much as possible. Gleiter grinds a substance into tiny particles and then combines them. In fact, he regards the defects on the interface as the main body of the entity. The metal block pressed by fine particles is a two-component material, which has a crystalline component and an interface component, and the interface component accounts for 50%. In the crystalline component, atoms are still in the original ordered arrangement, while in the interfacial component, there are a lot of defects on the interface, and the arrangement order of atoms changes. When the two-component material is made into nanometer scale, this special structure.

1987, Germany and the United States reported the successful preparation of titanium dioxide nano-ceramics (particle size: 12 nm), and its deformability and toughness were much better than those of single crystal and coarse crystal titanium dioxide ceramics. For example, nano-ceramics can be bent at 180℃ without cracks, and even if nano-ceramic parts have cracks at first, the cracks will not expand after a certain degree of bending deformation. 1989, scientists of American Business Machines Corporation (IBM) used the scanning tunneling microscope (STM) invented only in 1980s to move xenon atoms, and then used them to spell out three letters of IBM, and then arranged 48 iron atoms into Chinese characters "atoms". From 65438 to 0990, the first nanotechnology conference was successfully held in the United States, which marked the formal birth of a new discipline-nanotechnology, which closely combined micro-basic theory with contemporary high technology. 199 1 year, IBM scientists made a xenon atomic switch with a speed of 20 billion times per second. From 65438 to 0996, IBM's research institute in Zurich developed the world's smallest "abacus". The beads of this "abacus" are only nanometer in size and are made of the famous "carbon" bucky ball C60.

7. What does "nanotechnology" mean?

For some time, nanotechnology has appeared frequently in the media, and the advantages of nanotechnology, nanomaterials and products manufactured by nanotechnology have also been widely publicized. So, what is nanotechnology? This paper introduces this knowledge for beginners' reference.

. Nanometer is the unit of length, and the symbol is nm. 1nm =1nm = 10 m (billionth of a meter), which is about the length of10 atoms. Suppose that a hair has a diameter of 0.05 mm and is divided into 50,000 hairs on average in the radial direction, and the thickness of each hair is about 1nm.

. 1, the meaning of nanotechnology

The so-called nanotechnology refers to a brand-new technology to study the motion laws and characteristics of electrons, atoms and molecules in the scale of 0. 1~ 100 nanometers. In the process of studying the composition of matter, scientists found that several or dozens of countable atoms or molecules isolated on the nanometer scale show many new characteristics, and the technology of manufacturing equipment with specific functions by using these characteristics is called nanotechnology.

The main differences between nanotechnology and microelectronics are: nanotechnology studies the realization of specific functions of equipment by controlling single atoms and molecules, and it works by using the fluctuation of electrons; Microelectronics technology mainly realizes its function by controlling the population of electrons and works by using the particle nature of electrons. The purpose of people's research and development of nanotechnology is to achieve effective control of the entire micro-world.

Nanotechnology is a comprehensive subject with strong cross-cutting, and its research content involves the vast field of modern science and technology. From 65438 to 0993, the International Steering Committee of Nanotechnology divided nanotechnology into six sub-disciplines: nanoelectronics, nanophysics, nanochemistry, nanobiology, nanofabrication and nanometrology. Among them, nano-physics and nano-chemistry are the theoretical basis of nano-technology, and nano-electronics is the most important content of nano-technology.

.2, the characteristics of nano-electronic devices

The performance of electronic devices manufactured by nanotechnology is much better than that of traditional electronic devices.

The working speed is fast, and the working speed of nano-electronic devices is 1000 times that of silicon devices, so the product performance can be greatly improved. Low power consumption, the power consumption of nano-electronic devices is only11000 of that of silicon devices. There is a lot of information storage. A 5-inch CD less than the palm of your hand can store all the books of at least 30 Beijing libraries. Small size and light weight can greatly reduce the size and weight of various electronic products.

8. What is nanotechnology

For some time, nanotechnology has appeared frequently in the media, and the advantages of nanotechnology, nanomaterials and products manufactured by nanotechnology have also been widely publicized. So, what is nanotechnology? This paper introduces this knowledge for beginners' reference.

. Nanometer is the unit of length, and the symbol is nm. 1nm =1nm = 10 m (billionth of a meter), which is about the length of10 atoms. Suppose that a hair has a diameter of 0.05 mm and is divided into 50,000 hairs on average in the radial direction, and the thickness of each hair is about 1nm.

. 1, the meaning of nanotechnology

The so-called nanotechnology refers to a brand-new technology to study the motion laws and characteristics of electrons, atoms and molecules in the scale of 0. 1~ 100 nanometers. In the process of studying the composition of matter, scientists found that several or dozens of countable atoms or molecules isolated on the nanometer scale show many new characteristics, and the technology of manufacturing equipment with specific functions by using these characteristics is called nanotechnology.

The main differences between nanotechnology and microelectronics are: nanotechnology studies the realization of specific functions of equipment by controlling single atoms and molecules, and it works by using the fluctuation of electrons; Microelectronics technology mainly realizes its function by controlling the population of electrons and works by using the particle nature of electrons. The purpose of people's research and development of nanotechnology is to achieve effective control of the entire micro-world.

Nanotechnology is a comprehensive subject with strong cross-cutting, and its research content involves the vast field of modern science and technology. From 65438 to 0993, the International Steering Committee of Nanotechnology divided nanotechnology into six sub-disciplines: nanoelectronics, nanophysics, nanochemistry, nanobiology, nanofabrication and nanometrology. Among them, nano-physics and nano-chemistry are the theoretical basis of nano-technology, and nano-electronics is the most important content of nano-technology.

.2, the characteristics of nano-electronic devices

The performance of electronic devices manufactured by nanotechnology is much better than that of traditional electronic devices.

The working speed is fast, and the working speed of nano-electronic devices is 1000 times that of silicon devices, so the product performance can be greatly improved. Low power consumption, the power consumption of nano-electronic devices is only11000 of that of silicon devices. There is a lot of information storage. A 5-inch CD less than the palm of your hand can store all the books of at least 30 Beijing libraries. Small size and light weight can greatly reduce the size and weight of various electronic products.