Metallurgy refers to the process and process of extracting metals or metal compounds from minerals and making metals into metal materials with certain properties by various processing methods. Metallurgy has a long history of development, from the Stone Age to the subsequent Bronze Age, and then to the large-scale development of modern steel smelting. The history of human development is fused with the history of metallurgy.
Electricity is an energy source powered by electrical energy. Discovered in the 1870s, the discovery and application of electricity set off a second wave of industrialization. It has become one of the three scientific and technological revolutions in the world since the 18th century in human history, and science and technology have changed people''s lives since then. The emergence of large-scale power systems in the 20th century is one of the most important achievements in the history of human engineering science.
Cement, powdered hydraulic inorganic cementing material. After mixing with water, the slurry can be hardened in air or in water, and can firmly bond sand, stone and other materials together. The mixture of early lime and volcanic ash and modern lime and volcanic cement, which is used to bond the concrete made of crushed stone, not only has higher strength after hardening, but also can resist the erosion of fresh water or salt water.
It is an important part of the chemical industry, plays an important role in the development of the national economy, and is one of the pillar industrial sectors in our country. Petrochemical refers to the processing industry that uses oil and natural gas as raw materials to produce petroleum products and petrochemical products. Petroleum products, also known as oil products, mainly include a variety of fuel oils (gasoline, kerosene, diesel, etc.) and lubricants, as well as liquefied petroleum gas, petroleum coke.
Mine refers to an independent production and management unit with a certain mining boundary. The mine mainly includes one or more mining workshops (or pits, mines, open-pit stopes, etc.) and some auxiliary workshops, and most mines also include beneficiation plants (coal washing plants). The size of the mine scale should be commensurate with the economic and reasonable service life of the mine, only in this way can capital construction costs be saved.
Papermaking is one of the four great inventions of China. In the Western Han Dynasty, people already understood the basic method of making paper. In the Eastern Han Dynasty, the eunuch CAI Lun summed up the experience of his predecessors, improved the papermaking process, and used plant fibers such as bark, hemp heads, rags, and old fish nets as raw materials to make paper, which greatly improved the quality of paper.
Due to the harsh working conditions of petroleum underground, many downhole tools bear the load for a long time and are used in the working conditions of corrosion and wear, resulting in premature failure and failure, and thus shortening their life. For example: oil plunger, large rotor journal, sleeve, bearing bush, oil drill collar, wear plate, wear band, etc., but these parts are often very expensive.
Wind power generation refers to the conversion of wind kinetic energy into electrical energy. Wind energy is a clean and pollution-free renewable energy, which has long been used by people mainly through windmills to pump water, grinding, etc. People are interested in how to use wind to generate electricity. The use of wind power is very environmentally friendly and the amount of wind energy is huge, so it is increasingly valued by countries around the world.
Water industry refers to the industrial chain composed of raw water, water supply, water saving, drainage, sewage treatment and water resource recycling. Water industry is one of the most important urban basic service industries in China and even in all countries and regions in the world, and daily production and life are inseparable from urban water supply.
Shipbuilding is a specialized profession that predates recorded history. Ship building and ship repair is a mixed industry of commerce and military, generally referred to as the "maritime industry", in the early primitive society, primitive ancestors lived on fishing, hunting and fishing, and the scope of activity was limited to the area very close to the water.