Pyridine, 2-bromo-4-fluoro-

Mercury is often made of gold, but its chemical properties are different.
Mercury, under normal conditions, is a liquid. It is the only liquid gold, with white light and vulgar water. Its melting temperature is low, -38.87 ° C, and the boiling temperature is not high, 356.6 ° C. The chemical properties of mercury are determined, and it is often not oxidized under normal conditions. However, it can be oxidized and combined to form mercury oxide. Mercury is soluble in oxidizing acids, such as nitric acid, to form mercury. And mercury can form an alloy with more gold, which is made of mercury.
, which is heavy gold, is gray, and the surface is easily oxidized to form a dark gray film. The melting temperature is 327.5 ° C, and the boiling temperature is 1740 ° C. The chemical properties of mercury are highly reactive, and it is easy to react with oxygen, water and carbon dioxide in the air to form carbonate. It can be slowly soluble in dilute acids, sulfuric acid and nitric acid, and the reaction is stopped due to the formation of soluble sulfuric acid and sulfuric acid on the surface.
In addition, mercury is characterized by its chemical properties of its usual liquid and phase, and its chemical properties and chemical properties are easily oxidized in the air. The difference in chemical properties between the two makes it have different uses in various fields.

2-%E6%BA%B4-4-%E6%B0%9F%E5%90%A1%E5%95%B6%E5%9C%A8%E5%8C%96%E5%AD%A6%E5%8F%8D%E5%BA%94%E4%B8%AD%E5%B8%B8%E7%94%A8%E4%BA%8E%E4%BB%A5%E4%B8%8B%E5%87%A0%E7%A7%8D%E5%9E%8B%E5%BC%8F%E7%9A%84%E5%8F%8D%E5%BA%94%EF%BC%9A
###1. 9-%E9%85%B8%E5%8F%8D%E5%BA%94
9-%E9%85%B8%E5%8F%8D%E5%BA%94%E4%B8%AD%EF%BC%8C2-%E6%BA%B4-4-%E6%B0%9F%E5%90%A1%E5%95%B6%E5%B8%B8%E4%BD%9C%E4%B8%BA%E7%89%B9%E5%AE%9A%E7%9A%84%E9%85%B8%E5%8F%8D%E5%BA%94%E5%8F%82%E4%BD%93%E3%80%82%E5%A6%82%E5%9C%A8%E4%BC%98%E9%85%B8%E5%8F%8D%E5%BA%94%E4%B8%AD%EF%BC%8C%E5%AE%83%E5%8F%AF%E4%BD%9C%E4%B8%BA%E7%89%B9%E5%AE%9A%E9%85%B8%E5%8F%8D%E5%BA%94%E7%9A%84%E6%8C%87%E7%82%B9%E8%B4%A8%E7%89%A9%EF%BC%8C%E5%85%B7%E4%BD%93%E6%96%B9%E5%BC%8F%E5%A6%82%EF%BC%9A
\ [\ text {2 -}\ alpha\ text {- 4 -}\ beta\ text {-}\ text {sterenone}\ xrightarrow [\ text {certain conditions}] {\ text {specific reagents}}\ text {generated products}\]
During this process, the structure of 2 -\ (\ alpha\) - 4 -\ (\ beta\) -sterenone will change, and it will be converted into the target product through a series of reactions. The location and manner of its participation in the reaction are determined by the reaction conditions and the reagents used. In such reactions Its unique structure allows it to precisely guide the reaction in a specific direction, generating products with specific structures and functions, and is often used in the field of organic synthetic chemistry to construct complex steroid compound structures.
###2.5 - 10% E1 elimination reaction
In some systems involving E1 elimination reactions of compounds such as halogenated hydrocarbons or alcohols, 2-\ (\ alpha\) -4-\ (\ beta\) -stenolone can be used as a special additive or reactant environmental modulator. For example, in the E1 elimination reaction of certain halogenated hydrocarbons:
\ [\ text {R-X}\ xrightarrow [\ text {presence of 2 -}\ alpha\ text {-4-}\ beta\ text {-sterenone}] {\ text {heating}}\ text {R-H + X} ^ -\]
2 -\ (\ alpha\) -4-\ (\ beta\) -sterenone may affect the rate and selectivity of the reaction by interacting with reaction intermediates or transition states. It may change the electron cloud distribution of the reaction system, making it easier for halogen ions to leave, or stabilize the generated carbon cation intermediates, thereby promoting the elimination reaction, and affecting the configuration and regioselectivity of the generated olefin products. In some fine organic synthesis, it helps to obtain a specific configuration of olefin products.
###3. Nucleophilic Substitution Reaction
In the nucleophilic substitution reaction scenario, 2 -\ (\ alpha\) -4 -\ (\ beta\) -sterenones can interact with nucleophiles or substrates if they are in the reaction system. For example, when the nucleophilic agent Nu\ (^ -\) attacks the substrate R-L containing the departing group L:
\ [\ text {R-L + Nu} ^ -\ xrightarrow [\ text {presence of 2 -}\ alpha\ text {- 4 -}\ beta\ text {- sterenone}] {\ text {reaction conditions}}\ text {R - Nu + L} ^ -\]
2 -\ (\ alpha\) - 4 -\ (\ beta\) - sterenone can affect the attack of the nucleophilic test agent through spatial or electronic effects Direction and velocity. It may form a weak interaction with the substrate, changing the reactivity check point of the substrate, so that the nucleophilic substitution reaction can selectively occur at a specific location, providing a controlled way for the synthesis of organic compounds with specific substitution modes. In drug synthesis and total synthesis of natural products, it is of great significance for the precise construction of the target molecular structure.

If you want to make tools for two canals and four rivers, there are three methods. The first is the method of dredging canals. As recorded in "Tiangong Kaiwu", water conservancy is at stake, and smooth river channels are essential. When the farm is idle, gather the men to use shovels and hoes to dredge the canals. First measure the depth and width of the river channel, and mark the blockage. The men are divided into several teams, from the upstream to the bottom, and clean up section by section. The silt and sundries at the bottom of the river are dug up and transported to other places for proper placement to prevent pollution. In this way, the river can be guaranteed to flow smoothly, reduce water damage, and facilitate water transportation.
The second is the method of building embankments. The embankment is firm, so that the river can be protected. Select solid materials such as clay, sand and gravel, and build them in layers according to the topography. At the beginning of the construction of the embankment, the baseline should be determined first, and the rope and ink should be used as the degree to make the embankment straight. Each layer of filling is about a foot thick, and it is compacted with pestles and mortars, until the soil layer is as solid as stone. The embankment depends on the depth of the river and the fluctuation of the water, and it is probably several feet higher than the normal water level. And plant willows and grass on the embankment, its roots can fix the soil, and the leaves can be bermed to prevent wind and waves from eroding.
The third is the method of making the gate. The gate is used to open and close the water, and the water can be adjusted. The foundation is made of boulders, and it is cemented with lime, glutinous rice juice, etc., to make it strong and abnormal. The gate is made of solid wood, and it is outsourced with iron sheet to prevent corrosion. The opening and closing of Set up a gate at the intersection of the river and at the turning point of the terrain. When it is dry, the gate will be opened to divert water for irrigation, and when it is flooded, the gate will be closed for flood control. In this way, both water transportation and irrigation can be properly adapted.
All these three methods complement each other. Dredging the canal makes the water smooth, building the embankment to ensure the safety of the river, and regulating the water conservancy by making the gate. According to this, the two canals and four rivers can be completed, the flood can be eliminated, and the benefits of water transportation irrigation can be prosperous.

2-% mercury-4-deuterium is toxic to its market application field. It is liquid at room temperature and has a metallic luster. It is useful in many fields.
First, in the chemical industry, mercury and its compounds are often catalysts. In the chlor-alkali industry in the past, mercury cathodic method was used to electrolyze salt water, and mercury could help generate chlorine gas and caustic soda. However, due to its toxicity, it is gradually replaced by ion membrane method.
Second, in the instrument manufacturing industry, mercury is often placed in thermometers and barometers due to the characteristics of thermal expansion and contraction. Look at the change of temperature or air pressure, and the rise and fall of mercury columns to show the number. However, due to its toxicity, it accidentally breaks the mercury-containing meter, and mercury evaporates in the air, causing harm to the human body. Today, there are many alternative products.
Third, in the metallurgical industry, mercury can be used to refine precious metals such as gold and silver. Using mercury to form amalgams with gold and silver, the precious metals in ores are separated, and then the amalgam is heated to evaporate the mercury and obtain pure precious metals.
As for deuterium, it is an isotope of hydrogen. In the field of nuclear energy, heavy water (a compound of deuterium and oxygen) is used as a decelerator and coolant for nuclear reactors, which can slow down neutrons and maintain the stability of nuclear reactions. In the field of chemical research, deuterium is used to label compounds to track the process of chemical reactions and clarify the reaction mechanism. And in the medical field, the research and development of deuterium-containing drugs is gradually emerging, and may have unique pharmacological properties and efficacy.
When using mercury, caution should be taken, because its toxicity can cause damage to human nerves, immunity, reproduction and other systems. The application of deuterium also needs to be in accordance with scientific norms to ensure safety and efficiency.

Mercury is a liquid metal at room temperature. It is silver-white and has a metallic luster. Its density is quite high, reaching 13.59 g/cm ³. Its melting and boiling points are very different from those of ordinary matter. The melting point is -38.87 ° C, and the boiling point is 356.6 ° C. Mercury has good electrical conductivity, but its thermal conductivity is slightly inferior. Its surface tension is high, so it often aggregates into small balls in the plane.
And 4-hydrogen, this may refer to the water composed of deuterium (² H) and oxygen (heavy water, D _ 2O O), the appearance of heavy water is similar to that of ordinary water. They are both colorless, odorless, and odorless liquids, but the physical properties are slightly different. The density of heavy water is higher than that of ordinary water, about 1.107 g/cm ³, the melting point is 3.82 ° C, and the boiling point is 101.42 ° C.
The chemical properties of mercury are relatively stable, and it is not easy to react with oxygen at room temperature. However, when heated, it can combine with oxidation to form mercury oxide. Mercury can form amalgam with various metals. The chemical properties of heavy water are similar to that of ordinary water, and it can participate in many chemical reactions, but the reaction rate may be different from that of ordinary water. Because the mass of deuterium is greater than that of hydrogen, the relevant chemical bond energy is different from that of ordinary water. In the nuclear industry, heavy water is often used as a decelerator and coolant for reactors to adjust the speed of neutrons and ensure the smooth progress of nuclear reactions.