6-BROMO-PYRIDINE-3-CARBALDEHYDE

Mercury is a highly toxic substance, and its use is crucial in the art of alchemy. In the ancient field of alchemy covered in "Tiangong Kaiwu", the use of mercury has many aspects.
First, mercury is a metal with active chemical properties and is often used as the basic raw material for alchemy. The ancients believed that through a specific refining process, mercury can be combined with other medicines to generate pills with miraculous effects. For example, when refining some outer alchemy, mercury will be co-refined with lead, sulfur and other substances. Mercury and sulfur easily combine to form mercury sulfide, which is Dan Sha. In the eyes of alchemists, Dan Sha is an important medicinal ingredient. They believe that after many refinements, Dan Sha can remove toxicity, retain its essence, and prolong life after taking it, and become immortal.
Second, due to its fluidity and metallic luster, mercury symbolizes a mysterious power in the concept of alchemy. The ancients held the idea of "the unity of heaven and man" and "the symmetry of all things", and felt that the characteristics of mercury echo some mysterious forces between heaven and earth. During the refining process, the state of mercury changes, such as heating and turning into gas, and then condensing into liquid after cooling, just like the cycle and change of life. Alchemists hope to simulate natural creation and refine medicinal pills containing mysterious forces of the universe.
Third, mercury can also be used as a medium in the process of alchemy. Some drugs that are difficult to synthesize directly can be synthesized by the action of mercury. Mercury can dissolve some metals and form amalgam. During alchemy, different metals can be evenly mixed in the form of amalgam, which is more conducive to refining medicinal pills with uniform composition and high quality.
However, it needs to be understood that although the ancients had high hopes for the role of mercury in alchemy, modern science has proved that mercury and its compounds are toxic. Long-term consumption of mercury-containing medicinal pills will not prolong life, but will seriously damage human health, lead to mercury poisoning, and cause many diseases.

The method of making mercury has existed in ancient times. There are many methods, and each has its own subtlety.
One of them is the method of burning Dan sand. For Dan sand, that is, mercury sulfide. "Baopuzi Inner Chapter" says: "Dan sand is burned into mercury, and the accumulation changes into Dan sand." The method is to take Dan sand and place it in a closed vessel and calcine it with fire. Dan sand is decomposed by heat, sulfur and oxygen combine to form sulfur dioxide and escape, and mercury precipitates. This is the use of the chemical properties of Dan sand to obtain mercury through chemical reaction.

The second is the method of bile alum. Gallalum, that is, copper sulfate pentahydrate. Co-dispose of bile alum with metals such as iron. Because the metal activity of iron is stronger than that of copper, a displacement reaction occurs, and copper is replaced. At the same time, an appropriate amount of mercury-containing minerals or mercury salts are added to the reaction system, and mercury can be obtained through complex chemical reactions.
The third is the heating cinnabar method. Cinnabar is also a mineral form of mercury sulfide. The cinnabar is placed in a special furnace to be heated in a suitable heat. The cinnabar is decomposed by heat, and the mercury is volatilized, and mercury can be obtained by condensation collection. This requires precise control of temperature and heat. If the temperature is too low, the decomposition of cinnabar is incomplete; if the temperature is too high, mercury is easily lost.
The fourth is hydrometallurgy. The mercury-containing ore is leached in a specific solution, and the mercury is dissolved in the solution in the form of ions. After precipitation, replacement and other processes, mercury ions are converted into metallic mercury and precipitated. This process requires fine regulation of solution composition, concentration and reaction conditions to obtain pure mercury.
All kinds of production methods rely on the wisdom and practice of the ancients. Although the technical conditions were limited at that time, its achievements were remarkable, laying the foundation for the development of later chemistry.

Lead and mercury are the beauty of hardware, the finest in heaven and earth, and comparable to extraordinary things. Lead is heavy in quality, black in color and brilliant in essence, feminine in nature, but it has the ability to accumulate. "Joining the Agreement" says: "When Hu Fan is thrown into the fire, the bad color is still lead." This is the characteristic of lead. It can be restored to its original truth in case of fire, which seems to be a wonderful way to return to the original.
Mercury, shaped like a flowing bead, is white and shining, and has an extremely agile nature. It is yang and fickle. It often shuttles between things with its lively state. "Baopuzi" says that mercury "can digest gold and silver and turn it into mud, and those who paint the body can eliminate all diseases", which shows the miraculous effect of the god of mercury.
The two of lead and mercury are interdependent and mutually restricting. Lead is the house of mercury, and mercury is the soul of lead. The gravity of lead can make the flying of mercury, and the agility of mercury can open the occlusion of lead. In the way of alchemy, the combination of lead and mercury can become a great medicine.
And the nature of lead and mercury is not limited to alchemy. It also has deep meaning in the human body. In the human body, the kidney belongs to water, which hides essence, and the lead-like submersion; the heart belongs to fire, which hides the spirit, and the agility of mercury-like. The heart and kidney intersect, like lead and mercury, and the body and mind are congenial, and the life is double cultivation.
The physical properties of lead and mercury, the heavy color of lead is black, the flowing color of mercury is white, a static and a moving, a yin and a yang, mutual symmetry, is the most wonderful thing between heaven and earth, and its implication is far-reaching and infinite. It has a crucial position in various fields such as Dan Dao and health preservation. It is sincerely a treasure of heaven and earth and a god of nature.

Lead and mercury are the heroine of hardware, the spirit of heaven and earth. Its nature is the strongest, its quality is the strongest, but it also has many chemical characteristics. It is related to the way of alchemy and ingestion, and this is what you describe.
Lead, black and dignified in color, has a sinking nature. "Baopuzi" says: "Lead is white in nature, and red is thought of as Dan; red is thought of as Dan, and white is thought of as lead." When lead is smelted by fire, it initially melts into a liquid, like mercury, but black and heavy in color. If it is smelted by charcoal fire for a long time, lead can oxidize with the air, while the oxide of raw lead turns yellow in color, and it is refined again, or it is a red pill. Its nature is hot and dry, and it has the ability to remove evil and yin.
Mercury, at room temperature, flows into liquid, dazzling, and extraordinary agility, so it is also called mercury. Mercury is lively and volatile. If it enters the air, it will be inhaled or harmed. It is very important in the art of alchemy. Mercury can be fused with many metals to form amalgam, which is one of the major characteristics of mercury. In ancient alchemy, mercury was often used as a medium to make various medicines merge. If combined with lead, it can be formed into an amalgam of lead and amalgam. This alloy can change wonderfully under the regulation of heat.
The combination of lead and mercury requires precise control of the heat. If the heat is too high, the mercury is easy to evaporate and dissipate; if the heat is not high, the lead and mercury are difficult to melt, and the medicine cannot be used. " According to the Agreement of Participation: "Gold enters the fire, and its color does not lose its essence. Since its establishment, the sun and the moon have not lost their brightness, and gold has not lost its weight, and the sun and the moon have the same shape as usual." This is based on the ratio of gold to lead and mercury, which means that in the process of alchemy, although it is refined by fire, its essence should be kept, and it can become a pill.
The chemical characteristics of lead and mercury, for the ancient alchemists, are the mystery of exploring longevity. Although lead and mercury are very toxic in today's view, the experience accumulated by the ancients in the process of alchemy is also the germ of chemical knowledge, and has its own unique value and significance in the history of traditional Chinese science and technology.

The price of a shark varies according to time, place and quality.
In time, the season changes, and the price fluctuates. When it is abundant, the sea race is concentrated, and the city is numerous, and the number of sharks is abundant in the city. The price is flat, or it has dropped. This is the reason why the price is abundant and the price is low. If it is worth the time when its production is thin, there are many seekers and few suppliers, and the price must rise to meet the changes in supply and demand.
In the land, the distance between land and water, the difference between near and far, is also the key to the price. In the coastal land, the sharks are easy to obtain, and the fishing cost is small, so the price is flat. However, if it is transported inland, the journey is long and it is difficult to keep it fresh, and the cost, such as the transportation of boats and carts, and the preservation of fresh-keeping tools, are all tired of the price, so the price is double that of the seashore.
For those who are of high quality, the size, fat, and fresh rot of the nail shark are all related to the price. Those who are big and fat, have thick meat and taste, and everyone is competing for it, and the price is high. Those who are small and barren, have little taste and thin meat, and there are few buyers, so the price must be low. As for freshness, fresh nail sharks are delicious and abundant, and what people want is also expensive; if they are slightly rotten, no one will care, and even if they are sold cheaply, it may be difficult to get.
Therefore, if you want to know the price of a shark in the market, you must judge the time and the place, and distinguish its quality. The time is smooth and the place is appropriate, and the price is high if the quality is excellent; when the place is far away, the price is low if the quality is poor. The price of the market is inseparable from the balance between supply and demand and quality.