Principle of Allergen Reaction
Allergy reactions are caused by some people being overly sensitive to the substances (allergens) they come into contact with. When a sensitive individual comes into contact with a foreign, harmless substance (an allergy), the immune system will overreact and the body will produce a type of protein specific to the allergy. These IgE-bound to the high-affinity receptor on mast cells and basophils. When the allergy entered the body again and met with these bound molecules, the form of the immune receptor would change from a dimmer to a monolith. This change in form would lead to the exposure of the protein sites of the relevant signaling pathways, which would activate the downstream signaling pathways, causing allergic reactions such as vasodilation and bronchiectomy. In severe cases, it could cause allergic shock. In an allergic reaction, the affected organs or tissues will be infiltrated by a large number of inflammatory cells (especially those that are not activated), and a high concentration of IgE will appear in the serum. Read more exciting novels for free
Biuret and protein reaction principle
The principle of the reaction between biuret and protein was that biuret could react with copper sulfuric acid to form a purple substance. This might be caused by the peptidic bond structure in the biuret molecules. The nitrogen atom of the peptidic bond would form a purple complex with Cu2 + ions. Because there was also a peptidic bond structure in the protein, such a reaction would also occur. We called the purple reaction between the compound containing the peptidic bond structure and copper sulfuric acid solution "biuret reaction". In other words, as long as the molecules contained a peptidic bond, this characteristic purple reaction would generally occur. It wasn't that biuret reacted directly with the protein, but the reaction between the peptidic bond in the protein and copper ions. It was the same reaction type as biuret and copper ions. It was a " biuret reaction." When carrying out experiments related to the biuret reaction, biuret reagent A was a strong base, and biuret reagent B was copper sulfuric acid. When using it, add A to the protein solution first, shake it up, and then add B. Strong base and copper sulfuric acid can denature the protein, but this does not affect the purple reaction, because the essence of protein degeneration is that the spatial structure is destroyed, causing it to settle and lose its physiological activity. However, the bond structure and the sequence of the protein chain are generally not destroyed. <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>
Reaction Principle of Acid and Nitrite
The principle of the reaction between the two substances was that the reaction between the two substances would produce NaCl2, H2O, NO, and NO2. The reaction equation was 2NaNO2 + 2HQ = 2NaCl2 + H2O + NO + NO2. This was mainly due to the fact that the nitrogen acid was unstable and would decompose quickly. Moreover, nitrogen acid was a weak acid. <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>
Reaction Principle of Toothpaste and Iodine
The components of the toothpaste were composed of zinc-citrate, sodium-glyconate, and sodium-oh. These components could react with the iodine-like substance in the tincture to form the iodine-like substance. Generally, the iodine-like substance was only slightly pale yellow, so when the tincture was dripped into the toothpaste water and stirred, the color of the tincture would disappear. <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>
The Light Reaction Principle of Purple Light
The reaction principle of the purple light was as follows: The fluorescent reaction of a purple light lamp was based on the principle of luminescence. When a violet light (a violet flashlight) shone on certain substances, these substances would selectively absorb the violet light emitted by the violet light. The molecules would be stimulated, and they would emit visible light of the same wavelength and different intensity. When the light stopped, the fluorescence disappeared. When the infrared rays hit the fluorescent substance, there were three general situations: part of the infrared rays were reflected; part of the infrared rays were absorbed by the fluorescent substance; and part of the infrared rays were transmitted. The fluorescence occurred due to the absorption of the fluorescent substance. After the fluorescent substance absorbed the infrared rays, the internal energy state of the molecules changed, showing a transition between different energy levels and releasing fluorescence. For the Lighthouse series of purple lamps, the principle of light was to bombard the special fluorescent material inside the lamp with electric arcs after being energized, and then produce purple spectrum light waves. The violet light could be divided into the UUA band (320 - 400 <anno data-annotation-id ="00000100 - 400a-400a-400a-800a-8000000000000"> wave-length </anno>), the UVP band (275 - 320 </anno>), the UVP band (200 - 275 </anno>), and the UVR band (100 - 200 </anno>). Among them, the fluorescent powder in the purple tube could convert the arc energy into long-wave violet radiation in the UVA-band, such as the UVA-band of 340 - 380 run, and the UVA-band of 365 run was more suitable for checking the fine traces of the collection and fluorescent anti-counterfeit work. <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>
Reaxff reaction force field principle
ReaxFF was a molecular force field based on bond level. It is commonly used in molecular dynamics simulations. Goddard and his collaborators at the California Institute of Technology suggested. In its simplest form, as a bridge between chemical quantum and the experiential force field, it used a set of relatively simple functions to describe the relationship between energy and geometry. For example, it used the EFF method to deal with the simple harmonic-wave equation of the condensed matter system. These equations were used to describe the stretching, compression, and bending of bond angles. However, the current reference materials did not have more in-depth information about its principle, so it was impossible to answer further. <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>
Reaction Principle of Dehydrating Alcohol into Ether
The alcohol group was first protonated, and then the oxygen atom of the other alcohol group attacked the protonated carbon with a pair of electrons, causing an Sn2 reaction, and then deprotonated to give ether. <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>
What is the reaction principle of firing porcelain?
Firing porcelain was a complicated process that involved many reaction principles. First of all, he needed to choose suitable raw materials, such as clay, porcelain stone, Quartz, etc., and crush and grind them into powder or granules. Then, it was molded. The common molding methods included manual molding (such as kneading, wheel molding) and mechanical molding (such as injection molding, squeezing). The molded product needs to be dried to remove moisture. It can be naturally dried or heated. The dried product entered the firing process, which could be divided into several stages, such as pre-firing, firing, and cooling. In the pre-burning stage, the organic matter and moisture in the product gradually burned and evaporated, and the crystallization and chemical reactions in the raw materials began to occur. During the firing stage, the temperature gradually increased, and the ceramic raw materials were agglomerated. As the temperature increased, the powder particles with a larger specific surface and higher surface energy in the green body changed in the direction of lowering the surface energy, and the material continued to migrate. The grain boundaries moved, the pores were gradually eliminated, and the particles were compressed. The particles combined with each other to form a dense structure. During this process, the green body would be densified at high temperatures. The driving force of the process was the surface energy. Smelting could be divided into two types: liquid phase and pure solid phase. Finally, in the cooling stage, the fired product should be slowly cooled to avoid internal stress and cracking. The control of temperature, time, and atmosphere during the entire firing process was very important. Different ceramic materials and products required different firing conditions. <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>
Principle and Phenomenon of the Reaction between Acid and Acid
The principle of the reaction between the two was that there was a lone pair of electrons in the nitrogen atom. When the nitrogen atom reacted with the acid, the lone pair of electrons of the nitrogen atom formed a coordination bond with the hydrogen ion in the acid to form an aminium salt. Take the reaction between hydrogen and hydrogen as an example. The reaction phenomenon is the production of a large amount of white smoke. The ion equation of the reaction was: [NH3 + H^+ = NH4 ^+]. From a microscopic point of view, the lone pair of electrons on the nitrogen atom in the nitrogen atom combined with hydrogen ions to form an amine ion. From a macro point of view, the reaction of the reaction of the formation of small white solid particles, dispersed in the air to form white smoke. <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>
The meaning of tempering into steel and the principle of chemical reaction
"Tempered into steel" meant to become very strong after a long period of training. The principle of the chemical reaction was to use pig iron as raw material for smelting steel. The carbon content of pig iron was higher (2% - 4.3%), while the carbon content of steel was between 0.03% - 2%. During the smelting process, the carbon in the pig iron reacted with oxygen to form carbon dioxide (C+O <2>= CO <2>), thereby reducing the carbon content in the pig iron. The excess carbon and other impurities contained in the pig iron were converted into gas or slag to be removed. In this way, the pig iron was refined into steel.
What is the principle of the reaction between a hydrogen and a hydrogen?
The reaction mechanism between alkyls and halos was a substitution reaction of free radical. In the reaction, the halo (such as pure chorine, pure bromine, and not chorine water or bromine water) under the conditions of light/heat/free radical initiator, X-X was split into two X-free radical, X -and the HX-H on the alkyls formed hydrogen halo, and the alkyls left the alkyls free radical, which then reacted with X-X to form X -, and the cycle reaction could continue. The reaction between an aromatic compound (such as alkyne and alkyne) and a hydrogen atom was mainly an addition reaction. The double bond in an aromatic compound was a sigma-bond and a pi-bond. The pi-bond was more unstable and easy to break. The double bond opened to become a single bond, and the broken small half bond formed a covalent-bond with the hydrogen atom. In addition, the addition reaction of the hydrogen atom with the unsatured carbon could also be carried out. Aromatic compounds could only be substituted with a catalyst (such as iron trihalide, aluminum trihalide, iron powder, etc.), except for very active compounds (such as aromatic amine, vitamins, etc.). Fatty acid could only be substituted with a catalyst of red phosphorus, which generally produced an alpha substituted product. <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>