What is molecular sieve effect, molecular sieve effect noun explanation Introduction to the concept

Molecular sieve. The effect is when a sample solution containing multiple molecular components slowly flows through the gel column.

, each molecule is moving in two different motions at the same time in the column, a vertical downward movement and an undirected diffusion motion.

A gel with pores is a zeolite. The pore size distribution of various molecular sieves has a certain range, with a maximum limit and a minimum limit. If the molecular diameter is larger than the maximum pore diameter of the gel, it will be completely excluded from the gel particles, which is called total exclusion.

Two fully excluded molecules, even if they are different in size, cannot be separated.

Molecules smaller in diameter than the smallest pore diameter of the gel can enter the entire pores of the gel. If both molecules can enter the pores of the gel, even if they differ in size, there will be no good separation. Therefore, a certain molecular sieve has its certain range of use.

1. The molecular sieve effect is that when a sample solution containing a variety of molecular components slowly flows through the gel chromatographic column, each number of imitation molecules carries out two different movements in the column at the same time, vertical downward movement and non-directional diffusion movement. Due to their large diameter, macromolecular substances are not easy to enter the micropores of gel particles, but are distributed between the particles and move faster during elution.

2. In addition to being able to diffuse in the gap between gel particles, small molecule substances can also enter the micropores of gel particles, that is, into the gel phase, potato residual fiber in the process of moving downward, diffuse from one gel to the intergranular space and then enter another gel particle, so that it continues to enter and diffuse, therefore, the downward movement speed of small molecule substances should lag behind the macromolecular substances, so that the large molecules in the sample flow first to destroy the column, the medium molecules flow out, and the smallest molecules flow out last, this phenomenon is called molecular sieve effect.

1. The charge effect is an important basic concept of space charge in semiconductors and the corresponding space charge effect. Problems are often encountered in semiconductor materials and devices, especially in the case of high currents, where space charge plays a decisive role in identification.

2. The molecular sieve effect is when the sample solution containing a variety of molecular components slowly flows through the gel chromatographic column, and each molecule carries out two different movements in the column at the same time, vertical downward movement and non-directional diffusion movement. Due to the large diameter of the macromolecular substance, it is not easy to enter the micropores of the gel particles, but is distributed between the particles, and the speed of movement is faster during elution. In addition to the small molecule substance can diffuse in the gap between the gel particles, can also enter the micropores of the gel particles, that is, into the gel phase, in the process of moving downward, diffuse from one gel to the intergranular space and then enter another gel particle, so that continuously enter and diffuse, therefore, the downward movement speed of the small molecule substance should lag behind the macromolecular substance, so that the large molecule in the sample flows out of the column, the medium molecule flows out later, and the smallest molecule flows out last, and this phenomenon is called the molecular sieve effect.

The main role of molecular sieves:A physical exclusion effect is carried out according to the size of the molecule.

1. Adsorption function: molecular sieve is mainly caused by molecular gravity, which produces a "surface force" on the fixed surface, when the fluid flows, some molecules in the fluid will do irregular movement and collide with the surface of the adsorbent, and the molecular agglomeration is produced on the fixed surface, and the number of molecules is reduced in the overall collision movement, so as to achieve the effect of separation. Because molecular sieves have strong polarity and Coulomb field inside their crystal holes, they show strong adsorption capacity for polar molecules (such as water) and unsaturated molecules.

2. Drying function: There is also strong polarity in the crystal cavity of the molecular sieve, which can have a strong effect with the molecules containing polar groups on the surface of the zeolite molecular sieve, or by inducing the polarization of the polarizable molecules to produce strong adsorption. Because the seiflet has a strong adsorption capacity for water and carbon dioxide, during the desulfurization of the molecular sieve, the molecular sieve has a strong adsorption capacity for small polar molecules such as water.

3. Sieving function: its pore size distribution is very uniform and neat, and when the molecular diameter is less than the diameter of the hole, the substance will enter the inside of the molecular sieve. So as to separate the molecular sieves of each type.

The types of molecular sieves are divided into 3A, 4A, 5A, etc., and when they are used in different industries and fields to achieve different use effects, they should be correctly selected according to the performance of different products.

The molecular sieve only allows substances smaller than its micropores to pass through, and has a barrier effect on large parts of the tardron substances, bacteria, etc. that are larger than its micropores.

A zeolite is an aluminosilicate compound with a cubic lattice. The molecular sieve has a microporous structure of the uniform imitation beam of the oak, its pore diameter is uniform, these holes can adsorb molecules smaller than its diameter to the inside of the pore cavity, and have preferential adsorption capacity for polar molecules and unsaturated molecules, so it can separate molecules with different degrees of polarity, different degrees of saturation, different molecular sizes and different boiling points, that is, it has the role of "sieve" molecules, so it is called molecular sieve.

Molecular sieve effect, biochemistry.

The term "chamber opening" refers to the fact that when a sample solution containing various molecules flows slowly through a gel column, each molecule is moving in two different ways at the same time within the column.

The zeolite effect is when a sample solution containing multiple molecular components slowly flows through the gel column, and each molecule undergoes two different movements in the column at the same time, vertical downward movement and non-directional expansion.

Loose movement. Due to their large diameter, macromolecular substances are not easy to enter the micropores of gel particles, but are distributed between the particles and move faster during elution. Small molecule substances except.

In addition to diffusion in the gap between the gel particles, it can also enter the micropores of the gel particles, that is, enter the gel phase, and in the process of moving downward, diffuse from one gel to the intergranular space and then enter another gel particle, and so on.

and diffusion, therefore, the downward velocity of small molecule substances should lag behind that of large molecules, so that the large molecules in the sample flow first out of the column, and the medium molecules flow out later, and the molecules are smallest.

This phenomenon is called the molecular sieve effect.

As a sample solution containing various molecules flows slowly through a gel column, each molecule moves simultaneously in two different motions within the column: a vertical downward movement and an undirected diffusion movement. Due to its large diameter, macromolecular substances are not easy to enter the micropores of gel particles, but can only be distributed between particles, so they move downward quickly during elution.

In addition to diffusion in the gap between gel particles, small molecule substances can also enter the micropores of gel particles, that is, into the gel phase, in the process of moving downward, from one gel to the particle gap and then into another gel particle, so that the downward movement speed of small molecule substances lags behind that of large molecules, so that the large molecules in the sample flow out of the column first, medium molecules flow out, and small molecules flow out last, this phenomenon is called molecular sieve effect.