2,3-pyridinediamine, 6-chloro-

Among the many materials and processes involved in "Tiangong Kaiwu", "2.3 - to the second aperture, 6 - halogen -" refers to the method of salt production.
The production of salt is related to people's livelihood, and it has been a long time. In the art of salt production, the treatment of brine is particularly critical. In the text, "to the second aperture", or the way of introducing brine. In the place of salt production, there are many specific facilities to attract brine. Or dig a well to extract underground brine, and above the wellhead, set up an aperture to allow the brine to flow out smoothly and guide the subsequent salt production process. This two aperture may be the key to controlling the flow and velocity of brine, so that the brine can enter the place of evaporation and crystallization in an orderly manner. < Br >
And "brine", that is, brine. Brine, an aqueous solution with a very high salt content. Its sources are diverse, including those that gush out from the ground, and seawater is evaporated and concentrated. In the salt making process, brine is the initial raw material. After brine is introduced into a specific place "to its two orifices", the key step of salt making is started. Or by natural evaporation of sunlight and wind, the water is gradually lost and the salt concentration is increased; or by fire, it accelerates the evaporation of water and promotes the precipitation of salt crystals.
Brine is as fundamental to salt making as ore is to metallurgy. Its quality and the amount of impurities it contains have a great impact on the quality of the final salt. Those who are good at salt making must be good at controlling brine. Check its concentration, distinguish its composition, and apply appropriate methods according to the characteristics of brine to obtain high-quality salt. Therefore, "brine" plays a pivotal role in the process of salt making, and "going to the second hole" is a key measure to guide brine in the initial steps of salt making, so that it can enter the subsequent process in an orderly manner, and start the process of salt generation.

Mercury is like mercury, which flows but does not stagnate. It is a liquid metal. Its color is silver-white, with a metallic luster, shining and eye-catching.
The density of mercury is quite high, about 13.6 times that of water. If you put something into mercury, everything floats on its surface, just like a boat on water. Its melting point is extremely low, minus 39 degrees Celsius, so at room temperature, mercury is in a flowing state, just like smart water. The boiling point is not very high, only 357 degrees Celsius. When heated, it easily turns into a gaseous state and escapes.
Mercury has good electrical conductivity and can flow current smoothly in circuit conduction, making electrical things operate as usual. However, it is also toxic. If you inadvertently inhale mercury vapor, or accidentally eat something containing mercury, it will poison your organs, injure your body, and cause illness. Mercury can slowly oxidize in the air to form mercury oxide, which is red in color and adheres to the surface.
The chemical properties of mercury are active and stable. It can form an alloy with many metals, called amalgam, which is widely used in metallurgy and other industries. And mercury can quickly combine with sulfur powder to form mercury sulfide. This property can be used for the treatment of mercury leakage. Sulfur powder is coated on mercury to make it into a non-toxic substance to avoid poisoning.

2% 2C3 points to its dioxin, which is a chemical substance, the scientific name is tricarbon dioxide. 6-Xenon - has unique chemical properties.
Tricarbon dioxide is a colorless gas with high reactivity. Its structure is like three carbons are connected, and one oxygen is connected at each end, in the shape of O = C = C = O. Due to its special molecular structure and poor stability, it is easy to participate in many chemical reactions under specific conditions. In case of active reagents, it can often exhibit electrophilic or nucleophilic reaction characteristics, or many reactions such as addition and decomposition occur.
As for xenon, it is a group of rare gases. In the past, everyone thought that the chemical properties of rare gases were stable and difficult to react. However, with the progress of science, starting with Bartlett, it was found that xenon can form many compounds. The chemical properties of xenon are slightly active in rare gases, and can combine with elements with high electronegativity such as fluorine and oxygen. Like xenon hexafluoride (XeF), xenon tetrafluoride (XeF) and xenon trioxide (XeO 🥰). Xenon hexafluoride is a colorless crystal with strong oxidation and fluorination ability; xenon tetrafluoride is also a colorless crystal that can fluorinate many substances; xenon trioxide is an unstable compound that is prone to explosion in case of vibration or heat, and also has strong oxidation.
One is a highly active oxide, and the other is a slightly active xenon in rare gases. Its chemical properties are of unique research value in the field of chemistry, adding a colorful touch to the road of chemical exploration.

The production method involved in "February to March, go to its axillary, irrigation every six days" in "Tiangong Kaiwu" is a key link in the cultivation of young bamboo in the process of bamboo paper manufacturing.
In the initial stage of bamboo paper manufacturing, it is necessary to carefully cultivate young bamboo. From February to March, the growth of young bamboo is in a specific period, and at this time it is operated "to its axillary". The meaning of "to its axillary" is to deal with the axillary part of young bamboo accordingly. Bamboo axillary is where the bamboo joints are connected to the branches. Proper operation of it can promote the better growth of young bamboo and lay the foundation for the subsequent acquisition of papermaking raw materials. This may be to treat the bamboo axils such as thinning buds and fertilizing to adjust the nutrient distribution and growth trend of young bamboo.
"Irrigation every six days" is related to the irrigation link in the growth process of young bamboo. Irrigation is carried out every six days to provide suitable water for the growth of young bamboo. Water is extremely critical to the growth of young bamboo, and reasonable irrigation can ensure that the root system of young bamboo can fully absorb water and maintain its normal physiological metabolism and growth and development. Too frequent or too little irrigation is not conducive to the growth of tender bamboo. The frequency of irrigation every six days is a result of long-term practice, which can enable tender bamboo to obtain just the right amount of water nourishment at this growth stage and ensure its thriving growth, thus producing high-quality and high-fiber tender bamboo, providing high-quality raw materials for subsequent bamboo paper manufacturing. These production methods contain the accurate grasp and clever application of plant growth laws by the ancients in papermaking practice.

I think what you are asking is about the price range of dialum and hexaboron in the market. However, what is recorded in "Tiangong Kaiwu" is mostly the craftsmanship and products at that time. At the current price, there may be no direct correspondence in the book.
In the past, "Tiangong Kaiwu" was written, focusing on the technical process and the origin of the product, and the price change was not recorded in detail. Because of the price, it often moves with the world, supply and demand, and region.
In today's market, the prices of dialum and hexaboron vary according to their purity, quality, origin, and market supply and demand. For dialum, or used in chemical, printing and dyeing industries, the price may vary due to fluctuations in process costs and market demand. Hexaboron is also widely used, common in electronics, metallurgy and other fields, and its price is also affected by many factors.
If you want to know the exact price range, when you look at today's chemical market information, industry reports, or ask industry businesspeople and experts. They often involve market transactions and can know the approximate current price. Or you can check the chemical product trading platform, which has real-time price display, so you can get the current price range of dialum and hexaboron in the market. However, the price is volatile, so you must explore it at any time.