What are denitrifying bacteria? What is nitrification vs. denitrification?

When the soil is deficient in oxygen, nitrate is reduced to nitrite.

and further reduce nitrite to ammonia and free nitrogen bacteria. Bacteria that can reduce nitrate and produce molecular nitrogen are called denitrifying bacteria.

Such as denitrifying bacillus and so on. The bacteria are widely distributed and are abundant in sewage, soil and manure, and can turn nitrate into ammonia and nitrogen under anoxic conditions.

Discharge cooling is another type of convection cooling. Unlike regenerative cooling, the coolant used for exhaust cooling absorbs heat to the thrust chamber and is discharged out of the combustion chamber instead of entering the combustion chamber to participate in combustion. Direct drain coolant reduces the thrust chamber specific impulse, so the coolant flow for drain cooling needs to be minimized while only using drain cooling at the outlet section of the nozzle that is relatively less heated.

There is also radiative cooling, in which the heat flow is transferred from the combustion products to the thrust chamber, and then the heat is radiated by the thrust chamber wall to the surrounding space. Radiative cooling is characterized by simplicity and small structural mass. It is mainly used in the extension section of large nozzles and the thrust chamber of small thrust engines using high-temperature resistant materials.

When cooling in the thrust chamber of the tissue, a relatively low temperature liquid or gas protective layer is established on the surface of the thrust chamber wall to reduce the heat flow to the thrust chamber wall, reduce the wall temperature, and achieve cooling. Internal cooling is mainly divided into three methods: internal cooling (shield cooling), membrane cooling and diaphoretic cooling of head tissues. After the internal cooling measures are adopted in the thrust chamber, the mixing ratio near the wall of the combustion chamber is different from the optimal mixing ratio in the central area (in most cases, the near-wall layer rich in fuel is used) due to the need to reduce the temperature of the protective layer, resulting in the uneven distribution of the mixing ratio along the cross-section of the combustion chamber, so that the combustion efficiency is reduced to a certain extent.

Membrane cooling is similar to shield cooling in that it cools the thrust chamber wall by establishing a uniform and stable coolant film or air film protective layer near the inner wall surface, except that the coolant used to establish the protective layer is not injected by the injector, but is supplied through a special cooling belt. The cooling band is generally arranged in a cross-section of the combustion chamber or the convergence section of the nozzle. There can be several cooling bands along the length of the combustion chamber.

In order to improve the stability of the membrane, the coolant often flows through the gaps or small holes in the cooling belts, and when sweating is used, the thrust chamber wall or part of the inner wall is made of porous material with a pore diameter of tens of microns. Porous materials are usually sintered with metal powders or pressed with metal mesh. In this case, the number of pores per unit area is increased by making the micropores in the material as evenly distributed as possible.

The liquid coolant penetrates into the inner wall, creating a protective film that reduces the density of the heat transferred to the wall. When the flow rate of liquid coolant used for sweat cooling is above a certain threshold, a liquid film is formed near the wall of the thrust chamber. When the coolant flow rate is below the critical flow, the inner wall temperature will be higher than the coolant boiling point at the current pressure, and some or all of the coolant will evaporate, forming an air film.

In addition to the above thermal protection, there are other thermal protection methods such as: ablation cooling, thermal insulation cooling, hot melt cooling and composite protection of chamber walls. 3. Thermal protection scheme of high enthalpy gas generator Based on the above methods and the actual situation, the thermal protection method of high enthalpy gas generator is obtained.

The combustion chamber of a high-enthalpy gas generator differs from that of a liquid rocket engine, eliminating the front thrust chamber part, making its structure simpler and more effective. Then, the thermal protection involved is the thermal protection part of the combustion chamber wall. As the fuel enters the combustion chamber, it quickly decomposes and releases large quantities.

Nitrification refers to amino acids.

The process of converting the removed ammonia into nitric acid under the action of nitrite bacteria and nitric acid bacteria under aerobic conditions. Denitrification refers to the biochemistry in which bacteria reduce nitrogen (N) in nitrate to nitrogen (N) through a series of intermediate products. Process.

a) Nitrification.

Under aerobic conditions, the process of oxidizing ammonia nitrogen to nitrite nitrogen and nitrate nitrogen through the action of nitrite bacteria and nitrate bacteria is called biological nitrification.

ii) Denitrification.

The process of reducing NO2--N and NO3--N to N2 due to the action of facultative denitrification bacteria (denitrifying bacteria) under hypoxic conditions is called denitrification. The electron donors (hydrogen donors) in the denitrification process are a wide variety of organic substrates (carbon sources).

1. Nitrifying bacteria are a class of aerobic bacteria, including nitrifying bacteria and nitric bacteria. Living in aerobic water or sand plays an important role in the nitrogen cycle water purification process.

2. Nitrifying bacteria preparation is a treatment agent used to control the concentration of self-generated ammonia in aquaculture pond water, which is not only quite convenient to use, but also can play an immediate effect, so it is more and more popular with aquarists. When used, the agent can be directly spread in the pool, and it will soon be able to exert the effect of ammonia removal.

3. Commercially available nitrifying bacteria preparations can be divided into two types: live bacteria and dormant bacteria, and fishermen can choose and use them according to their own needs. The former is made from the living organisms of bacteria, and their activity can be seen under a microscope. The latter are made from dormant bacteria, which cannot be seen to be motile under a microscope.

4. The physiological group of denitrifying bacteria includes a wide range of saprophytic microorganisms. In the case of normal oxidation of organic matter, it relies on the free state of O2, while in the case of respiration of gas, it relies on the bound oxygen of nitrate, which is the acceptor of hydrogen.

5. Denitrifying bacteria can live in the medium of nitrate used as a nitrogen source, and it can use this compound as both energy metabolism and substance metabolism. Denitrifying bacteria reduce nitrate to nitrite and further reduce nitrite to ammonia and free nitrogen under the condition of insufficient oxygen in the soil.

Their enzyme system reduces to NH3, and microorganisms can assimilate this nitrogen to synthesize cellular material.

6. It is made by fermentation of excellent denitrification strains through special technology. The strain has strong denitrification ability, can use nitrous nitrogen and nitrate nitrogen as nitrogen sources, simple activation, rapid reproduction, remarkable effect, and 24-hour visible effect. It has special effects for the situation of high nitrite in aquaculture water;

For the overbloom of algae, the water body can consume a large amount of nitrogen nutrients, cut off the nitrogen nutrients of algae, and maintain a good water color; The strains can survive under both sufficient dissolved oxygen and anaerobic conditions and undergo denitrification reactions to optimize the physical and chemical environment of the substrate.

7. The main function of denitrifying bacteria: reduce nitrite in the water body, make it produce harmless nitrogen, and relieve the harm of nitrite. Depletes nitrogen nutrients, inhibits algae overbloom, and purifies water bodies. Inhibits pathogenic bacteria. Improved substrate.

Summary. What does not belong to denitrifying bacteria is the total nitrogen remover, which is a chemical substance that can effectively convert nitrogen compounds in water into nitrogen, so as to reduce water pollution and improve water quality.

It is a chemical substance that can effectively convert nitrogen compounds in water into nitrogen, so as to reduce water pollution and improve water quality.

Can you tell us more about that?

It is a chemical substance that can effectively convert nitrogen compounds in water into nitrogen, so as to reduce water pollution and improve water quality.