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              Release date: 2022-12-19 16:39:50

              35 core technologies that China urgently needs to overcome! High pressure plunger pump is one

              Today, a total of 35 "stuck neck" technologies reported by "Science and Technology Daily" are sorted out into a simplified version and shared with you.

              There is only one thing I want to explain: this is just the tip of the iceberg!

              01 Lithography machine

              "These "details" make it difficult for China to see top lithography machines" (Science and Technology Daily, April 19)

              The precision of the photolithography machine used to manufacture chips determines the upper limit of chip performance. In the "Twelfth Five-Year Plan" scientific and technological achievements exhibition, the best lithography machine produced in China has a processing accuracy of 90 nanometers. This is equivalent to the level of the Pentium 4 CPU launched in 2004. And foreign countries have achieved more than ten nanometers.

              There are two work tables that move synchronously in the lithography machine, one with negative film and one with film. The two need to be always in sync with an error of less than 2 nanometers. The two worktables went from static to dynamic, and the acceleration was similar to that of a missile launch. When working, it is equivalent to two large planes going side by side from takeoff to landing. A knife is stretched out from one plane to engrave characters on the rice grains of the other plane, which cannot be damaged.

              02 chip

              "ZTE's "chip" disease, China's heart disease" (Science and Technology Daily, April 20)

              Low-speed optical chips and electrical chips have been domestically produced, but high-speed chips are still all dependent on imports. The mass production accuracy of the most advanced chips in foreign countries is 10 nanometers, while in my country it is only 28 nanometers, which is two generations behind. According to reports, in many fields in computer systems, general electronic systems, communication equipment, memory equipment, and display and video systems, the share of domestic chips in my country is 0.

              03 operating system

              "Losing the opportunity, the pain of a big country without a self-developed operating system" (Science and Technology Daily, April 23)

              Ordinary people see the prosperity of China's IT industry and think that the technology gap is not big, but it is not. Three American companies monopolize the operating systems of mobile phones and personal computers. The data shows that in 2017, the market share of the Android system reached 85.9%, and that of Apple's IOS was 14%. Other systems have only 0.1%. This 0.1% is basically Microsoft Windows and BlackBerry in the United States. Without Google paving the way, smartphones would not be so popular, and the price for Chinese mobile phone manufacturers to use Android for free is that they may be "run out of food" at any time.

              04 Aero engine nacelle

              "No house for the homeless, the difficulty of the nacelle of domestic aero-engines" (Science and Technology Daily, April 24)

              The cabin where the engine is placed on the aircraft, commonly known as the "house", is one of the most important core components of the aviation propulsion system, and its cost accounts for about 1/4 of all engines. The nacelle needs to cover the engine to reduce flight resistance; its air intake must also have anti-icing and deicing capabilities; during flight, the engine must be protected from interference and work normally; on the ground, it is necessary to facilitate engine maintenance and repair , once the nacelle is damaged, it may cause serious engine accidents during flight. The larger the nacelle, the higher the technical difficulty. Our country is still blank in this important field. According to all the public information, there is no specialized agency for independent research and development of nacelles in my country, and the relevant colleges and universities do not seem to have set up relevant disciplines.

              05Tactile sensor

              "Sensor inspection, "domestic touch" by dull robots" (Science and Technology Daily, April 25)

              Tactile sensors are the core components of industrial robots. The strict requirements of precision and stability have prevented most enterprises in our country from moving towards tactile sensors. At present, most domestic sensor enterprises are engaged in the production of gas, temperature and other types of sensors. In an industry with more than 100 companies, there are almost no sensor manufacturers producing tactile sensors. The Japanese array sensor can distribute 100 sensitive elements in a substrate with a size of 10 cm × 10 cm, and the price is 100,000 yuan, while domestic products are mostly one-point type, generally 100 yuan each.

              06 Vacuum evaporation machine

              "Shortage of Vacuum Evaporation Machines: Shadows on High-End Displays" (Science and Technology Daily, April 26)

              The "heart" of OLED panel manufacturing. Japan's Canon Tokki monopolizes the high-end market and holds the throat of the industry. The industry's annual output forecast for it is usually between a few units and a dozen units. Money can't buy it, that's what it is. Canon Tokki can control the error of evaporating organic light-emitting materials onto the substrate within 5 microns (1 micron is equivalent to 1% of the diameter of a hair), and no other company's evaporation machine can achieve this accuracy. At present, there is no enterprise producing vapor deposition machines in our country, and we have no right to speak in this field.

              07 Mobile phone radio frequency devices

              "Radio Frequency Devices: The Embarrassment of Mobile Phones" (Science and Technology Daily, May 7)

              On the motherboard of a mobile phone, 1/3 of the space is radio frequency circuits. The development trend of mobile phones is thinner and lighter, with less power consumption, more frequency bands, and greater bandwidth, which poses challenges to radio frequency chips. Radio frequency chips convert digital signals into electromagnetic waves. 4G mobile phones must support more than a dozen frequency bands, and the information bandwidth is tens of megabytes. In 2018, the RF chip market was US$15 billion; the high-end market was basically monopolized by Skyworks, Qorvo and Broadcom, and Qualcomm also had a place. Another key component of radio frequency devices - filters, the gap between domestic and foreign is even greater. The multi-billion dollar market for high-end filters used in mobile phones is entirely owned by foreign RF device giants such as Qorvo. China is the world's largest mobile phone producer, but it cannot manufacture high-end mobile phone radio frequency devices. This requires solid accumulation of materials, craftsmanship and design experience.

              08iCLIP technology

              ""Targets" are hard to find, and domestic innovative drugs are very confusing" (Science and Technology Daily, May 8)

              iCLIP is an emerging experimental technology and one of the most critical technologies for the development of innovative drugs. Its invention allows people to abandon sophisticated observation instruments, but also determine where RNA (ribonucleic acid) and protein "intersect", and even read the "code" of the site. iCLIP technology is difficult, just like finding a person in a sea of thousands of people. It is necessary to find one or several definite binding points from billions of base pairs, and the accuracy can be imagined. Foreign research teams have launched a "technical competition" in this field, and research papers are staged in turn every few months. Domestic laboratories have very little mature experience.

              09 Heavy duty gas turbine

              "The Decline of the Gate of Life", the Death of the Blades of Heavy-duty Gas Turbines" (Science and Technology Daily, May 9)

              Gas turbines are widely used in ships, trains and large power plants. my country has the capability of self-governing light-duty gas turbines; however, refueling still basically relies on the introduction. The world's largest re-ignition manufacturers are mainly GE of the United States, Mitsubishi of Japan, Siemens of Germany, and Ansaldo of Italy. The cooperation with China comes with strict conditions: the design technology is not transferred, and the core hot-end component manufacturing technology is not transferred, and only non-core components are allowed to be manufactured locally in the form of licenses. The lack of autonomy means that an important part of my country's energy security is still controlled by others, and there is a risk of being "stuck".

              10

              lidar

              "Lidar is stunned, making automatic driving very tangled" (Science and Technology Daily, May 10)

              Lidar is a sensor with its own light source that actively emits laser light to sense the surrounding environment, just like bats use ultrasonic positioning. It is an essential component of self-driving cars and determines the evolution level of the self-driving industry. But in this field, domestic products have almost no right to speak. Among the self-driving cars that can go on the road at present, almost all those involving lidar are products of Velodyne of the United States. Its lidar products are the industry standard, accounting for more than 80% of the market share.

              11 airworthiness standards

              "Airworthiness Standards: Another difficult hurdle for domestic aviation development" (Science and Technology Daily, May 11)

              In order to obtain a flight certificate for an aero-engine, it must pass a very strict "airworthiness" standard system verification, covering design, manufacturing, verification and management. But at present, in the international arena, the airworthiness certification of FAA and European Aviation Safety Agency (EASA) has the greatest influence and the highest recognition. Although China is basically consistent with the FAA in terms of regulatory requirements, due to the lack of domestic aero-engine models and the lack of practical engineering experience, my country's airworthiness regulations lack corresponding technical support. The airworthiness verification work of the actual model has become a pass that is stuck outside the airspace of other countries.

              12 high-end capacitor resistor

              "Without these tricks, we can't reach high-end capacitors and resistors" (Science and Technology Daily, May 14)

              Capacitors and resistors are golden supporting roles in the electronics industry. China is the largest market for basic electronic components, which consumes trillions of resistors and capacitors a year. But the best consumer grade capacitors and resistors, come from Japan. The capacitor market is more than 20 billion U.S. dollars a year, and the resistance is also on the order of tens of billions of U.S. dollars. The so-called high-end capacitor resistance, the most important thing is that the same batch should be as consistent as possible. Japan has done the best in this regard, and there is a big gap between domestic companies. The products of domestic enterprises are mostly low-end products, and they are relatively weak in technology, materials and quality control.

              13 Core Industrial Software

              "Core Industrial Software: China's "No Man's Land" for Intelligent Manufacturing" (Science and Technology Daily, May 17)

              China's core industrial software field is basically "no man's land". The absence of industrial software has brought troubles to smart manufacturing. When the industrial system is complex to a certain extent, it is necessary to replace human brain calculation with computer-aided industrial software. For example, the "essential artifact" EDA industrial software for chip design and production. Compared with domestic EDA tools and mainstream EDA tools in the United States, there is no difference in design principles, but there is a big gap in software performance, which is mainly reflected in the lack of support for advanced technologies and processes. , There is a "generation gap" between the foreign advanced EDA tools. The three foreign EDA giants, Cadence, Synopsys and Mentor, account for 70% of the global annual total revenue of this industry. It is urgent to develop independent industrial operating system + independent industrial software system.

              14ITO target

              "Can't burn large target materials, flat panel display manufacturing depends on others" (Science and Technology Daily, May 18)

              ITO targets are not only used to make liquid crystal displays, flat panel displays, plasma displays, touch screens, electronic paper, organic light-emitting diodes, but also used in solar cells, antistatic coatings, transparent conductive coatings for EMI shielding, etc., and have a wide range of markets around the world. The thickness of the ITO film varies according to functional requirements, generally ranging from 30 nanometers to 200 nanometers. On the issue of size, domestic ITO target material companies have rarely made breakthroughs, and back-end flat panel display manufacturers have to rely on others. Sintering large-size ITO targets requires a large sintering furnace. Foreign countries can make a single target with a width of 1,200 mm and a length of nearly 3,000 mm, but domestic targets can only be manufactured with a width of no more than 800 mm. In terms of output efficiency, the monthly output of Japanese-style equipment can reach 30 to 50 tons, while our annual output is only 30 tons—and the price of importing a piece of equipment costs 10 million yuan, which is tantamount to sky-high prices for small domestic companies .

              The annual consumption of ITO targets in my country exceeds 1,000 tons, about half of which are imported for the production of high-end products.

              15 core algorithms

              "Algorithms are not good, domestic industrial robots are a bit "stupid"" (Science and Technology Daily, May 22)

              China has become the world's largest robot application market for five consecutive years, but high-end robots still rely on imports. Due to the lack of mastery of the core algorithm, the key indicators of domestic industrial robots such as stability, failure rate, and ease of use are far inferior to those of the "Four Families" of industrial robots: FANUC (Japan), ABB (Switzerland), Yaskawa (Japan), and KUKA ( Germany) product. The core algorithm gap is too large, which leads to poor stability of domestic robots and high failure rate. The gap in the algorithm is not only reflected in the core controller, but also slows down the response speed of the servo system.

              Every time the robot completes an action, it needs the core controller, servo driver and servo motor to cooperate. For a single servo system, domestic robots have high dynamic and static precision, but high-end robots generally have more than 6 servo systems at the same time, and it is difficult to achieve good control effects with traditional control methods.

              16 aviation steel

              "Aviation steel is not too hard, and domestic large aircraft take off and land without evidence" (Science and Technology Daily, May 23)

              Regardless of takeoff or landing, the landing gear is the only part that supports the aircraft, especially during the landing phase of the aircraft, the load it carries not only comes from the weight of the fuselage, but also the huge vertical momentum of the aircraft. Therefore, the material strength of the landing gear must be excellent, and it can only rely on special steel. At present, the 300M steel in the United States is the most widely used. This material adopts vacuum heat treatment technology, which avoids hydrogen permeation, brightens the surface of parts, and has no defects such as oxidative decarburization, carburization, and grain boundary oxidation, and improves the surface quality. However, the domestic super-strength steel used to make landing gear sometimes has problems such as point defects, sulfide inclusions, coarse grains, internal cracks, and hydrogen penetration during heat treatment. These problems are all related to insufficient purity during the smelting process. Therefore, there is still a big gap between my country and the United States in terms of high-purity smelting technology, and there is a lot of room for improvement.

              17 milling cutter

              "For high-speed rail rails, domestic milling cutters are embarrassing tasks" (Science and Technology Daily, May 24)

              With the rapid construction of high-speed rail in my country in recent years, the problem of rail maintenance has become more and more worrying for industry experts. If the maintenance is not in place, not only will the life cycle be damaged, but there will also be high risks. The dual-power electric drive milling and grinding maintenance robot equipment independently developed by our country - the milling and grinding vehicle known as the rail "emergency vehicle" can "escort" the rails. However, the milling cutter, the core component of the milling and grinding machine, still needs to be imported from abroad. The material of the milling cutter is a superhard alloy material. We already know the metal components in it, but we just don't know how they are mixed and synthesized, just like wondering about the secret recipe of a certain traditional Chinese medicine and the proportion of various medicinal materials.

              18 high-end bearing steel

              "High-end bearing steel, a short board in China's manufacturing industry that is difficult to fill" (Science and Technology Daily, May 25)

              As an indispensable core component in mechanical equipment, bearings support the mechanical rotating body, reduce its friction coefficient, and ensure its rotation accuracy. Regardless of whether it is an airplane, an automobile, a high-speed rail, or a high-precision machine tool or instrument, bearings are needed. This places high demands on its precision, performance, lifetime and reliability. While my country's shaft-making technology is close to the world's top level, but the material—that is, the steel for high-end bearings is almost entirely dependent on imports.

              The R&D, manufacturing and sales of high-end bearing steel are basically monopolized by the world's bearing giants Timken of the United States and SKF of Sweden. A few years ago, they established bases in Yantai and Jinan, Shandong respectively, purchased low-end materials in China, used their core technology to make high-end bearings, and sold them to the Chinese market at ten times the price. The addition of rare earths in the steelmaking process can make the original high-quality steel stronger. But how to add, this is the core secret of the world's bearing giants.

              19 high pressure plunger pump

              "High pressure plunger pump, a thorn in the throat of China's equipment manufacturing industry" (Science and Technology Daily, May 28)

              The hydraulic system is one of the key components of the equipment manufacturing industry. All engineering fields, where there are mechanical equipment, cannot do without the hydraulic system. The high-pressure plunger pump is the core component of high-end hydraulic equipment, known as the "heart" of the hydraulic system. The scale of China's hydraulic industry has become the second in the world in 2017, but the industry is large but not strong, especially high-pressure plunger pumps with a rated pressure of 35MPa and above, and 90% and above rely on imports. Compared with foreign brands, domestically produced hydraulic plunger pumps have a large gap in technological advancement, working reliability, service life, variable mechanism control functions, and dynamic and static performance indicators, which are basically equivalent to those of foreign countries in the early 1990s. Level.

              20 Aeronautical Design Software

              "Aviation software embarrassment, domestic aircraft design wears a "curse"" (Science and Technology Daily, May 30)

              Since the 1980s, the world's aviation industry has entered a new stage of digital design, and now it has reached a high degree of dependence that cannot be designed without software. Designing an aircraft requires at least a dozen kinds of professional software, all of which are products of European and American countries. Domestic design units not only have to invest huge sums of money to purchase software, but also wear steel rings on their heads. Once the "tightening spell" is recited, the entire aviation industry will be paralyzed. According to media reports, when designing the J-10 aircraft, the entire metal part of the main load-bearing structure of the main landing gear was commissioned to be manufactured abroad. However, after the production was completed, there was a problem with the retraction and retraction of the landing gear, and there was an error of 5 mm, so we had to order and manufacture again. Just this little error affected the delay of the first flight of the J-10 for eight or nine months. Without all-digital software support, any slight error may become a manufacturing nightmare.

              21 photoresist

              "China's semiconductor industry loses color due to photoresist" (Science and Technology Daily, May 31)

              Although my country has become the world's largest producer of semiconductors, the overall industrial chain of the panel industry is still relatively backward. At present, almost all photoresists used in LCD rely on imports, and the core technology has been monopolized by Japanese companies such as TOK, JSR, Sumitomo Chemical, and Shin-Etsu Chemical. Take BOE, which has certain international competitiveness, as an example. It has established 17 panel display production bases, 16 of which have been put into production. However, the photoresist used by BOE for high-end panels is still provided by foreign companies. The main components of photoresist are polymer resin, color paste, monomer, photoinitiator, solvent and additives. There are many technical difficulties involved in the development. Screening and control of monomers, control and stability of color paste fineness, product formulation design and optimization, product production process optimization and stability, end-use condition matching and tolerance adjustment, etc. Therefore, it is very difficult to develop and produce independently.

              22 high pressure common rail system

              "High-pressure common rail is useless, and domestic diesel engines are very hurt" (Science and Technology Daily, June 4)

              The electronically controlled diesel high-pressure common rail system is equivalent to the "heart" and "brain" of a diesel engine, and its quality will seriously affect the use of the engine. The diesel engine industry is an important equipment foundation to promote a country's economic growth and social operation. China is the main market and production country of diesel engines in the world, and in the domestic high-pressure common rail system market for electronically controlled diesel engines, companies such as Germany, the United States and Japan occupy a large share. Compared with the products of foreign advanced companies, the domestic high-pressure common rail system still has a certain gap in performance, function, quality and consistency, and the cost advantage is not obvious.

              23 transmission electron microscope

              "Our protein 3D high-definition photos rely on imported transmission electron microscopes" (Science and Technology Daily, June 6)

              The cryo-electron microscope can take high-definition 3D "color photos" of the microstructure, which is a powerful tool for life science research. The production capacity of the transmission electron microscope is one of the foundations of the cryo-electron microscope's manufacturing capacity. At present, there are only three manufacturers producing transmission electron microscopes in the world, namely JEOL, Hitachi, and FEI. There is no domestic enterprise producing transmission electron microscopes. The tools used to match the cryo-electron microscope all need to be original. If the parts are broken, no one can find someone to repair them. We can only wait for the parts to be mailed and replaced after they arrive. For Chinese cryo-electron microscope users, such an experience may last for a long time.

              24 roadheader main bearing

              "My own roadheader has to use other people's main bearings" (Science and Technology Daily, June 7)

              The main bearing, known as the "heart" of the full-section tunnel boring machine, bears the main load during the operation of the tunnel boring machine and is a key component of the cutter head drive system, and the working conditions are very harsh. Compared with the traditional rolling bearing with a diameter of only a few hundred millimeters, the diameter of the main bearing of the roadheader is generally a few meters, which is the most complex bearing, and the manufacture requires hundreds of processes. As far as the manufacturing capacity of the roadheader is concerned, the domestic roadheader is close to the world's most advanced level, but the most critical main bearings are all dependent on imports. Germany's Rothe Erde, IMO, FAG and Sweden's SKF occupy the market.

              25 microspheres

              "Microspheres: The Unbearable Lightness of National Industry" (Science and Technology Daily, June 12)

              Microspheres, one-thirtieth the thickness of a human hair. In the screen of a mobile phone, one hundred microspheres are used per square millimeter to prop up two glass panels, which are equivalent to a skeleton, and liquid crystals are poured into the gap between the two glass panels. Without it, the LCD screen you're staring at wouldn't be productive. Without microspheres, chip production, food safety testing, disease diagnosis, biopharmaceuticals, environmental monitoring... many industries will be in trouble. In the field of microelectronics alone, China imports microspheres worth tens of billions of yuan every year. In 2017, the LCD panel shipments in mainland China reached 33% in the world, and the industry scale is about 100 billion US dollars, ranking first in the world. But the key materials in this panel-spacer microspheres and conductive gold balls can only be provided by one or two Japanese companies in the world. These materials are also like chips, which are stuck in the neck.

              26 underwater connector

              "Underwater connection lacks domestic sharp weapons, and the submarine observation network is close to the fence" (Science and Technology Daily, June 13)

              In addition to ships and remote sensing satellites, the submarine observation network has become the third ocean observation platform - through which, humans can go deep into the water to observe and understand the ocean. If various cable observation platforms are compared to arms and legs, underwater connectors are like joints, which play an irreplaceable role in the construction, operation and maintenance of the submarine observation network system. At present, my country's underwater connector market is basically monopolized by foreign countries. Once the connector becomes a contraband, the construction and operation of the entire submarine observation network will be interrupted.

              27 Fuel Cell Key Materials

              "Without Three Key Materials, Commercialization of Fuel Cells Can't Be an Article" (Science and Technology Daily, June 14)

              Foreign fuel cell vehicles have achieved mass production, but my country's vehicle fuel cells are still in the stage of technical verification. The status quo of fuel cells for vehicles in my country is that there are almost no component manufacturers, no production companies for vehicle stacks, and only a very small number of fuel cell vehicles in commercial operation. A number of key materials determine the life and performance of fuel cells. These materials are not completely absent in our country, and some laboratory results have even reached the international level. However, there is no mass production line, and the fuel cell industry chain is still blocked. The key materials have been dependent on foreign countries for a long time. Once they encounter a sales ban, my country's fuel cell industry will have no basic support.

              28 high-end welding power supply

              "Domestic welding power supply is "dumb", and the robot's underwater operation is powerless" (Science and Technology Daily, June 20)

              my country is a big ocean country, with more than 3 million square kilometers of sea area, and is vigorously developing high-end marine resource development and marine rights protection equipment. Once the equipment in the sea has cracks or other failures, it needs to be repaired with welding equipment known as the "sewing machine" in industrial manufacturing. The realization of deep-sea welding depends on underwater robots. Although my country is the world's largest manufacturing base of welding power sources, with an annual production capacity of more than 10 million sets, high-end welding power sources are still basically monopolized by foreign countries. my country's underwater robot welding technology has been difficult to improve, because the high-end welding power supply technology is restricted by others. The full digital control technology of welding power source in foreign countries is relatively mature, while the domestic one is still dominated by analog control technology.

              29 lithium battery diaphragm

              "One layer of diaphragm, two heavens: domestic lithium batteries still need to see the sun" (Science and Technology Daily, June 21)

              As the "heart" of new energy vehicles, domestic lithium-ion batteries (hereinafter referred to as lithium batteries) are currently not "jumping" stably enough. Among the four core materials of the battery, the positive and negative electrode materials and the electrolyte have been localized, but the diaphragm is still a shortcoming. High-end diaphragm technology has a very high threshold. Not only does it require huge investment, but it also requires a strong R&D and production team, skilled technology and high-level production lines. High-end diaphragms are still heavily dependent on imports.

              30 medical imaging equipment components

              "Clumsy detectors blur medical images" (Science and Technology Daily, June 25)

              At present, most components of domestic medical imaging equipment rely on imports, and it will take at least 10 or 20 years to reach the current level of others. In traditional medical imaging (CT, MRI, etc.), the earliest patents in China are on average 20 years later than in the United States. In terms of the number of patents, the United States is 10 times that of my country. This means that the entire industry is completely in the hands of foreign companies. All intellectual property rights, all original achievements, and all scientific research accumulation are abroad, and China only accounts for a small part.

              31 ultra-precision polishing process

              "The road to the top of ultra-precision polishing technology is long and difficult" (Science and Technology Daily, June 26)

              How important the ultra-precision polishing process is in modern manufacturing, its application fields can directly explain the problem: integrated circuit manufacturing, medical equipment, auto parts, digital parts, precision molds, aerospace. "It is the soul of technology". The United States and Japan have firmly grasped the initiative in the global market, and their material composition and production process have always been a mystery. In other words, buying and using their products does not mean that their products can be imitated or even copied.

              32 epoxy resin

              "Epoxy Resin Insufficient Toughness, Domestic Carbon Fiber Lacks Strength" (Science and Technology Daily, June 27)

              The quality of carbon fiber is lighter than metal aluminum, but its strength is higher than that of steel. It also has the characteristics of high temperature resistance, corrosion resistance, fatigue resistance, and creep resistance. One of the key composite auxiliary materials is epoxy resin. But at present, the epoxy resin used in the high-end carbon fiber produced in China is all imported. At present, my country has been able to produce higher-end carbon fibers such as T800, but Japan's Toray mastered this technology in the 1990s. Compared with carbon fiber, my country's high-end epoxy resin industry lags behind the international situation more seriously.

              33 high strength stainless steel

              "The Rocket Engine "Rust Disease" That Can't Be Removed" (Science and Technology Daily, June 28)

              Steel materials used in rocket engines need to have various properties, among which high strength is an important indicator that must be met. However, the strength and anti-rust performance of stainless steel are contradictory bodies that are difficult to have at the same time. If the rocket engine material is seriously rusted, it will have a great impact. Relying entirely on the material itself to achieve both high strength and anti-rust performance is a worldwide problem. At present, most of my country's aerospace materials are foreign materials used in the 1960s and 1970s. Developed countries will strictly control the content of impurities in the production process. If the purity does not meet the standard, they will be returned to the furnace, but domestic manufacturers often lack this rigorous manner.

              34 Database Management System

              "Database Management System: China is still looking for the "correct way to open"" (Science and Technology Daily, July 2)

              At present, the two most popular database management systems in the world are Oracle and MySQL, both of which are products of Oracle Corporation. Competitors include products from IBM and Microsoft. Several American companies, Oracle, IBM, Microsoft and Teradata, account for most of the market share. Domestic products of database management systems also have a market share, but only a fraction, and their stability and performance cannot convince the market. Banks, telecommunications, electric power and other companies that require extreme safety will not consider domestic products.

              35 SEM

              "Scanning electron microscope "amblyopia", industrial manufacturing is difficult to see clearly" (Science and Technology Daily, July 3)

              Scanning electron microscope, a high-end electron optical instrument, is widely used in various research fields and industrial sectors such as materials, biology, medicine, metallurgy, chemistry and semiconductors. It is called "microscopic camera". At present, my country's scientific research and industrial sectors The scanning electron microscopes used are heavily dependent on imports. Among the hundreds of scanning electron microscopes purchased by my country at a cost of more than 100 million U.S. dollars each year, they are mainly produced in the United States, Japan, Germany and the Czech Republic. Domestic scanning electron microscopes only account for about 5%-10%.

              Source: Science and Technology Daily

              Author: Liu Yadong (Chief Editor of Science and Technology Daily)

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