2-pyridinemethanol, 3-fluoro-

2-% to his grandfather, what are the physical properties of the 3-river? This question is related to the principles of nature, and I will explain it in detail.
Water is the source of all things, its nature is very soft, but it can pierce stones. The water of the Wanfu River always flows endlessly, and its shape changes with the device, whether it is square or round, it can be adapted. This is the sign of its flexibility. The Tao Te Ching says: "The highest good is like water, and water is good for all things without dispute." The virtue of saying water can also be seen in its pliability.
Water is fluid, which is its remarkable physical property. In the river, the water runs down from the top, rushing forward without hindrance. Its flow speed varies according to the terrain and drop. When it encounters high hills, it will circle, and when it encounters low valleys, it will gather, and eventually return to the sea. This fluidity enables water to nourish all things, transport nutrients, and cycle back and forth between heaven and earth to maintain vitality.
Furthermore, water has buoyancy. Boats can be carried on the water, and people and goods depend on the buoyancy of water. The "Kaogong Ji" says: "To make a boat is to travel on the water." The ancients knew the buoyancy of water well, so they built boats to facilitate transportation. The buoyancy of objects in water is related to the amount of water discharged. This is a rule of physics.
The density of water is also its important property. Under normal conditions, the density of water is one gram per cubic centimeter, and this density keeps water in a specific state in the natural environment. When water freezes in winter, the density decreases, and the ice floats on the water, so that underwater life can survive, which is a wonder of nature.
The boiling point of water is 100 degrees, and the freezing point is zero degrees. When heated to the boiling point, the water turns into steam and rises into the air; when cooled to the freezing point, the water condenses into ice, which is as hard as stone. This change in temperature and the transformation of the state of water are not uncommon in life and natural phenomena.
The water of rivers, which combines many physical properties, plays a crucial role in the world. Its softness, flow, buoyancy, density, boiling point, freezing point and other properties, or nourish all things, or affect the climate, or for human use, are really natural treasures, worthy of our generation to explore in detail.

Mercury is the most overcast and good at flowing away. It is also a thing, white as silver, liquid at room temperature, agile and lively, like mercury spraying into the ground, all-pervasive.
Mercury has unique chemical properties. It has a certain metal activity, but compared with common metals, it has many peculiarities. When heated, it is easy to evaporate, curl up, and turn into gaseous mercury. This gas is invisible and colorless, but it is toxic. If inhaled into the human body, it will cause great harm.
Mercury can form alloys with a variety of metals, which are called amalgams. If it meets sodium, the two can combine and change each other's physical and chemical properties. In chemical reactions, mercury can often play a special role, either as a catalyst to accelerate the process of the reaction; or participate in the reaction to form novel compounds.
When mercury meets sulfur, the two combine rapidly to form mercury sulfide. This mercury sulfide is relatively stable in nature and has a vermilion color. In ancient times, it was often used in the production of pigments. This reaction is also one of the methods to deal with mercury pollution, which makes mercury change from an active state to a relatively stable state and reduces its harm.
Although mercury has many properties, its toxicity cannot be underestimated. In the natural environment, if mercury escapes, it will be transported along the food chain through biological enrichment, and eventually endanger human health. Therefore, when using mercury, be careful to prevent its harm.

2-%E5%90%A1%E5%95%B6%E7%94%B2%E9%86%87 is the essence of heaven and earth, born of the essence of the world, and the beauty of the world. Its shape is like a human being, and the gods are very special, often living in deep mountains and valleys, or in the fairy caves of the spring. The nature is very clear, I like the company of the sun, the moon and the stars, I suck the essence of heaven and earth, and I am in the mountains and rivers. Its life is long, and it can be used for a thousand years without decline. The world is full of mulberry, and I understand the wonders of creation.
3-% E6% B0% 9F, the source of things, the dependence of life. It flows endlessly, like the sky, and it is illusory. The nature of water is soft, and it can pierce stones. It is tangible in shape and weak. Its functions are many, and it is the foundation of people's livelihood. Irrigation of fertile fields, nourishing the life of things. In this way, it can nourish the five and six internal organs, and the spirit of the spirit; bathing, it can remove the body, and pass the blood.
And the water is also in the boat, so that the things can be connected to the four directions. Because of this, business is easy to travel, and culture is exchanged and integrated because of it. Rivers, lakes and seas, the water is extracted, and the water is hidden and hidden, so that there are many creatures. Water is in the world, like a mother is in her children. It is privately offered without seeking return.
Furthermore, the water is clear, and the world is declining. The water is clear, and the things are prosperous, and the people live in peace; the water is still in the water, and the coal is produced. Therefore, the people rule the water, and the Lord is sparse, so that the water can be used in the way, and it flows constantly. To keep one side of the water and soil safe, and to promote the symbiosis of things and things. The importance of water can be ignored!

If you want to make dienes, you can ask them. As for the synthesis of alkenes, there are many methods, which are described by you today.
First, the dehalogenation of halogenated hydrocarbons. Take halogenated hydrocarbons and heat them together with the alcohol solution of the strong base. The halogen atom and the hydrogen atom on the orthocarbon are removed in the form of hydrogen halide to form an ethylene. In this reaction, the structure of the halogenated hydrocarbon is very critical. If there is no hydrogen on the orthocarbon, it is difficult to form an ethylene. For example, 1-chloropropane is co-heated with an ethanol solution of potassium hydroxide to obtain propylene.
Second, alcohol is dehydrated. Using alcohol as raw material and concentrated sulfuric acid as a catalyst, heating is used to remove a part of water from Usually, the control of the reaction temperature is very important, and the temperature required for different alcohols is different. For example, ethanol is dehydrated to form ethylene at 170 ° C under the catalysis of concentrated sulfuric acid. If the temperature is not appropriate, such as at 140 ° C, the intermolecular dehydration of ethanol produces ether instead of ethylene.
Third, the partial hydrogenation of alkynes. Under the action of a specific catalyst, alkynes can be partially hydrogenated to alkenes. Commonly used catalysts include lindela catalysts. This method can selectively convert alkynes to cis-olefins. For example, acetylene is hydrogenated under the action of lindela catalysts to obtain ethylene; if liquid ammonia is used as a solvent and sodium is used as a reducing agent, alkynes can be reduced to trans-olefins. < Br >
Fourth, metathesis reaction of olefins. This is a relatively novel method. Using metal carbene as a catalyst, two olefin molecules exchange groups at the ends of the carbon-carbon double bond with each other and recombine to form a new olefin. This reaction condition is relatively mild, and the atomic utilization rate is high, so it is widely used in organic synthesis.
The above methods have their own scope of application and conditions, and should be selected according to the actual required olefin structure, raw material availability and reaction conditions and other factors.

The old man asked the craftsman: "When the copper of a sword is hidden or lost, what should be paid attention to?" The craftsman said: "When the copper of a sword is hidden, its quality is the first thing to be paid attention to. Pure copper must be selected, without impurities and flaws, and it can be the foundation of a good sword. If the copper is not pure, it is mixed with lead and tin. Although it has been refined, it is difficult to become a sharp weapon in the end. The hiding place should be dry and ventilated to avoid moisture and prevent it from rusting. If the copper is invaded by moisture, the surface is green and rust, and its quality is damaged, there will be many twists and turns when the sword is cast.
As for the time of losing, it is related to the way of transportation. Copper is heavy, and when handling, you need to be careful not to collide. If there is a bump, it will damage its appearance, or damage its internal quality. And the transportation equipment should be firm and smooth to prevent bumps on the way and damage to the copper material. Furthermore, when traveling, choose a safe path to avoid rough and difficult places, so as not to damage the copper material on the road.
Also, at the time of handover, check in detail. According to its quantity, check its quality, and match the specified specifications one by one. If there is any discrepancy, it should be identified immediately, and it should not be confused. A slight mistake will affect the casting of swords, and the quality of swords is also related to this. Therefore, the possession and transportation of copper should not be ignored. Pay attention to each section. Fang Bao's casting materials are appropriate, and the casting of good swords is expected.