pyridine-3-thiol

The main use of gypsum is for the needs of all things. According to the "Tiangong Kaiwu", the use of gypsum is quite extensive.
First, in the agricultural mulberry industry, gypsum benefits the soil. It can improve the soil quality, make the soil fertile, and help the growth of crops. Farmers sprinkle gypsum in the field, which can make the soil harmonious, and the crops can be nourished and flourished. In the genus of rice and wheat, it is used properly and the harvest is quite abundant.
Second, in metallurgy, gypsum is also used. When smelting, gypsum can be used as a mold material. Using gypsum to make molds can make the shape of the cast precise and the texture fine. Such as the casting of a bell tripod, with plaster as the mold, the cast thing is beautifully shaped and does not lose its rules.
Third, in the construction of houses, plaster is also indispensable. It can be made into plaster and used to apply walls. With plaster plaster plaster on the walls, the walls are smooth and moisture-proof. Inside the house, it is decorated with it, which is both beautiful and practical.
Fourth, in the way of medicine, plaster is also a good medicine. Its cold nature can clear away heat and purge fire. In the case of fever and thirst, plaster is often used by doctors to relieve the disease of the patient.
All these uses are the main use of plaster. It is of great benefit to agriculture, industry, medicine, and other things, and it is indeed a good material in the world.

Borax is cold and salty in nature. Its quality has several characteristics in physics.
The color of borax is often white, like frost and snow, delicate and shiny, and pure and flawless in appearance. Its shape is mostly crystalline, with distinct particles or lumps. The texture is relatively solid, and it feels cool to the touch, as if it contains a little cold meaning.
In terms of its solubility, borax is soluble in water. When placed in water, it gradually dissolves and fuses with water. However, the speed of dissolution is not instantaneous, and it takes a few hours to completely dissolve. When dissolved, it seems to change the temperature of the water slightly, but this change is not very significant.
Furthermore, borax has a certain degree of stability. Under normal temperature and environment, its properties are quite stable, and it is not easy to undergo chemical changes on its own, and it can maintain its own form and properties for a long time. However, if it encounters specific chemical substances, or under special temperature, pressure and other conditions, it will also occur corresponding chemical reactions, showing different characteristics.
Borax also has certain fusibility. In many fields such as metallurgy, it can play its role. When co-located with metals and other substances in a furnace, borax can reduce the melting point of metals, making them easier to melt. It is like paving a smooth way for the melting of metals, helping them to turn into liquids at relatively low temperatures and facilitating subsequent casting, processing, and other processes.

One night, my friend and I were discussing the physical properties of chemistry and whether the chemical properties of its -3-phosphoric acid are stable.
My friend was the first to say: "Those who are exposed to its -3-phosphoric acid may be unstable. The genus of phosphoric acid is mostly active and easy to combine with other substances to form new substances. And the state of -3 may change the structure of its electron cloud and increase its activity, so it is difficult to stabilize."
I thought about the difference and said: "Otherwise. The environment in which its -3-phosphoric acid is located is also the key. If the temperature and pressure are appropriate, and there is no strong reaction to the matter, it may be stable. Looking at many chemical examples, the properties of a substance are not only determined by its own structure, but also greatly influenced by external conditions. "
Friends retorted:" Although external conditions are involved, the essential structure is fundamental. The structure of its -3-phosphoric acid makes its electron distribution unusual. This innate difference makes the activity difficult to suppress. Even if the outside world is peaceful, it may not be stable for a long time. "
I also insist on my own opinion:" The wonders of chemistry are complex and changeable. There may be unknown factors that can help it stabilize. And the proof of the experiment is not clear, and Aneng only imagines that it is unstable based on the structure? "
After finishing speaking, my friends and I looked at each other and laughed. To cover the mystery of chemistry, we still need to study more experiments and investigate the physical properties in detail before we can obtain the true solution. The debate at this moment is just a matter of reason. Only after future evidence can we know whether the chemical properties of -3-phosphoric acid are stable or not.

The stone chalk is widely used in the process of synthesis.
First, in the pottery industry, the stone chalk is indispensable. "Kaogong Ji" says: "In the case of potters, the black grave is used for pestle, and the red one is used for short." The stone chalk is combined with various soils, and the soil properties can be adjusted. Make the viscosity and plasticity of the pottery suitable, so that the device can be regular and dense in texture. And the stone chalk can increase the fire resistance of the pottery, and it can be calcined without cracking through intense fire, so that it becomes a fine pottery.
Second, in the art of metallurgy, the stone chalk is also very useful. In ancient smelting, the ore often contained impurities, and the stone chalk was put into the furnace to synthesize with impurities. " Tiangong Kaiwu Hardware "contains:" Where iron furnaces use salt as a slag-making medium, stone chalk is used to build furnaces. "Stone chalk and impurities form slag, which floats on the molten iron, which is easy to separate, obtain the quality of fine iron, improve the purity of metal, and lay the foundation for casting good weapons.
Third, in the construction of buildings, stone chalk is an important material. The ancients relied on stone chalk to build walls and paint walls. The" Construction French "says:" Lime is used most today, or it is used for building walls, or it is used for painting walls. "The stone chalk is mixed with water, sand, etc. into mortar to strengthen the wall, making it difficult for wind and rain to invade. And after painting the wall, the wall is flat and white, which has a beautiful effect.
Fourth, in the path of medicine, chalk is also occasionally used. "Compendium of Materia Medica" records: "Chalk has a pungent, warm, and non-toxic smell. It is used to treat women's blood and gas cold pain, sore scabies and other diseases." Although it is not the main medicine, it can play the role of reconciling medicinal properties and assisting in the treatment of diseases in some prescriptions.
Therefore, in the synthesis of stone chalk, it involves pottery, metallurgy, architecture, medicine and many other fields, and has a deep impact on the production and life of the ancients.

The method of making cannons has been known in ancient times, and has been refined in the past generations. The first thing to make cannons is the material. If you want to make a cannon, you need to know the quality of the cannon, and the quality of the cannon is good, so that the cannon can be fired without cracking.
One is the need for smelting. The method of smelting is often used in ancient times. The method of smelting with a crucible is high-temperature melting with charcoal fire. The craftsman inspects the heat and waits for the water to boil, and the cannon floats up, skimming off the floating foam and lifting.
The second is the type of cannon. Use mud or wood cannon molds to refine. The shape and size of the mold determine the performance of the cannon. The mold wall needs to be smooth to prevent uneven water attachment to the wall of the cannon, causing defects in the gun body. < Br >
Third, polish the gun body. When the gun is formed, use tools such as grinding and grinding to repair the gun body. Make the gun bore smooth and the muzzle is straight. The gun bore is smooth, and the shot is shot out of the gun, and the range can be increased. The gun mouth is correct, and the road is fixed, and the hit is more accurate.
Fourth, the gun is broken. The new gun is completed, and the cannon is made in the field. First, a small amount of fire is fired, and the gun body is shaken and cracked. Increasing the fire volume, range and accuracy one by one. If the gun body is broken, it will be repaired or repaired immediately.
Fifth, accessories are matched. The aiming, mounting and other accessories of the cannon are also required. The aiming and positioning of the cannon seeks to be active and precise, and can be adjusted at high and low levels, left and right angles, and different eyes. The mounting needs to be fixed, and it can support the reaction force of the gun body.
Of course, building a cannon requires careful work by craftsmen, and each person can control it. Only then can we obtain excellent cannons, protect our territory, and protect our prestige.