5-bromopyridine-3-carbonitrile

"Tiangong Kaiwu" has a saying: "Where gunpowder, sulfur is pure yang, and nitrate is pure yin". Among them, sulfur is sulfur. In gunpowder, the main function of sulfur is extraordinary.
First, sulfur is flammable and can provide basic conditions for gunpowder combustion. When given a certain amount of energy from the outside world, sulfur is ignited first, and its combustion generates heat, which prompts the surrounding temperature to rise, creating a suitable thermal environment for the reaction of other ingredients in gunpowder, such as saltpeter and charcoal, just like igniting the fuze for subsequent reactions, triggering a chain reaction.
Second, sulfur can reduce the ignition point of gunpowder. The temperature required for the direct reaction of saltpeter and charcoal is quite high, and the existence of sulfur reduces the energy threshold required to start the reaction. This is like opening up a smoother path on a difficult mountain road, allowing gunpowder to react violently at relatively low temperatures, greatly enhancing the convenience and practicality of gunpowder use. In military, civilian and other fields, gunpowder can play a role without complicated conditions.
Third, sulfur has a profound impact on the reaction speed and stability of gunpowder. It can adjust the internal reaction process of gunpowder to make the reaction proceed more evenly and stably. In military applications, it can ensure that gunpowder provides a continuous and stable thrust at the moment of weapon launch, allowing projectiles such as projectiles to obtain the ideal initial speed and range; in civilian blasting, etc., it can also ensure the accuracy and reliability of the blasting effect, and avoid accidents caused by too fast or too slow reaction.
Therefore, sulfur occupies a key position in the composition of gunpowder, making gunpowder one of the core elements of important inventions in many fields of the world.

If you want to make the meat of the three animals in Wuxin sauce, there are various methods, which are described in detail as follows.
First, the selection of ingredients needs to be refined. For the three animals, cattle, sheep, and pigs are also. When choosing cattle, take their tendon meat, the meat is firm and the texture is delicate; sheep choose ribs, fat and thin, and the fat and fragrant meat is tender; pigs should choose pork belly, which is well-layered and rich in taste. Excellent selection of ingredients is the foundation of deliciousness.
Second, it is well-matched. Cut the selected meat into thin slices or small pieces, with uniform size and uniform thickness. The beef tendon meat can be cut into thin slices, about two points thick, which is convenient for tasting; the lamb ribs are cut into small pieces, which are easy to ripen and do not lose their shape; the pork belly is cut into small pieces, which can be evenly penetrated when stewed.
Third, marinate and taste. Prepare a large urn, with onion and ginger, pepper, star anise, cinnamon, fragrant leaves and other spices, accompanied by salt, sugar, cooking wine, light soy sauce and other seasonings, and mix evenly. Place the cut meat in the urn and rub it repeatedly to make the seasonings fully contact with the meat. Marinate for more than two hours, so that the meat can absorb the flavor of the spices.
Fourth, the method of making sauce. In another large kettle, add an appropriate amount of water, and then boil the marinated meat. First cook it over high heat, skim off the floating foam, wait for the meat to turn white, then turn to low heat and simmer slowly. In the meantime, chop up the five spices, that is, scallions, garlic, ginger, chives, and coriander. When the meat is cooked, add the five spices, stir well, and continue to cook for a while, so that the taste of the five spices can be integrated into the meat. Then add sweet noodle sauce, bean paste and other sauces according to the taste, stir and boil until the sauce is thick, the meat is wrapped in the sauce, and the aroma is overflowing, and you are done. The five spices sauce and three animals meat prepared in this way have a mellow taste and a tangy aroma. It can be used as a delicacy or a wonderful food to accompany meals.

Lead and mercury, the beauty of hardware, the finest of heaven and earth, its quality is strong, and its nature is soft. Lead, the essence of water in the north, black and heavy in color, its shape is round, and its nature is heavy. Mercury, the essence of fire in the south, red and light in color, its shape is flowing, and its nature is flying.
The quality of lead, as strong as stone, melts in case of fire, turns into a liquid, like the flow of water, and then after condensation, it returns to firm. Its specific gravity is quite large, and it can often fall when placed on top of other things. And lead has good ductility, which can be beaten into thin sheets or pulled into thin threads for the manufacture of many utensils. And lead can shield radiation, can be used as a protective material, and is of great use in medicine and engineering.
Mercury is different from lead, it is often liquid, like the luster of silver, so it is also called mercury. Mercury is agile, flows indeterminately, and is elusive. Its boiling point is low, and it is easy to turn into steam when heated, and soars into the air. Mercury is also toxic and should not be eaten by touch. However, mercury also has unique uses in alchemy and medicine. Ancient alchemists often used mercury to make alchemy, hoping to seek the medicine of longevity.
The two lead and mercury, one is rigid and the other is soft, one sinks and the other flies, one is black and the other is red, seemingly contradictory, but in fact they are interdependent and transformed into each other. In the way of alchemy, the combination of lead and mercury is the most important method. Lead can make mercury fly, mercury can make lead rigid, the two complement each other, to become the magic of medicinal pills. This is the physical nature of lead and mercury, between heaven and earth, each has wonders, and is an important foundation for all kinds of skills and alchemy.

In "Tiangong Kaiwu", it goes: "The genus of hardware has different types and functions. Lead is wet and heavy in nature, black in color and can produce mercury. Zinc is strong and brittle in nature, white in color and can be made of copper." In the case of lead and mercury today, among hardware, the chemical properties of lead are quite unique.
Lead is heavy and soft in quality, and has a color like ink. At room temperature, lead is stable but rarely changes, but it gradually melts when heated, like ice disappears in the warm sun. Lead is easy to oxidize, and its surface often rusts to protect it. When lead meets acid, the reaction is slow, but when it encounters strong acid, it melts into salt and escapes hydrogen.
As for mercury, it is the only metal that is liquid at room temperature. It is as agile as silver beads, slippery and difficult to catch. When it encounters lead and mercury, it can make mercury flow, causing it to gather and not disperse. This is the beauty of lead. The ancient alchemists, alchemy and pharmaceuticals, often used lead and mercury as the key, taking lead to make mercury, and seeking the medicine of longevity. Although it is much false, it can also be seen that lead and mercury are related.
Lead is also very useful in alloys. It is combined with tin to form solder, which has a low melting temperature and can be joined to metals; when combined with antimony, it can obtain hard lead, which is strong and durable, and can be used as a bearing. Lead compounds are also widely used, such as lead Dan, which is red and bright, and can be used as a pigment; and lead acid, which can be used in batteries to store electricity for energy.
Although lead is useful, it is also toxic. It enters the human body, accumulates and is difficult to discharge, and harms the nervous, blood, and digestive systems. Therefore, when using lead, be careful to prevent its harm and use its benefits, in order to be the best way.

In today's world, the market is unpredictable, and the prices of grains and fruits often fluctuate. As for the prices of 5-hydroxytryptamine and 3-methionine in the market, it is difficult to determine the exact value range.
Looking at the ancient city, the value of things often depends on the situation of supply and demand, the abundance of years, the distance of origin, and the difficulty of transshipment. Today's 5-hydroxytryptamine and 3-methionine follow this principle. < Br >
5-Hydroxytryptamine, or used in medical treatment, or involved in scientific research, its production requires technology and resources. If the supply is less than the demand, the price will increase; on the contrary, if the production is abundant and the demand is small, the price may drop. However, its production technology and strict quality control all affect its price.
3-methionine is useful in animal husbandry, medicine and other industries. Its price changes also depend on the price of raw materials, the difficulty of craftsmanship, and the degree of market demand.
Or those with close production areas, fine craftsmanship, and high production capacity may have relatively easy prices; if the origin is far away, the craftsmanship is poor, and the output is small, the price will be high.
If you want to know the exact price range of the two, you should visit various pharmaceutical shops and chemical shops in person, or consult informed people in the industry, or observe the reports of business information, so that you can get a near-real price. The market is impermanent, and only by observing it in real time can you know where the price is.