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Anonymous users2024-02-08Single crystal. Solid substances are divided into crystalline and amorphous. Crystals are divided into single crystals, polycrystals.
Single crystal. Refers to the molecules (atoms or ions) contained in the sample in three-dimensional space.
It is a state of solids that is arranged in a regular, periodic manner. Active pharmaceutical ingredients in chemical drugs.
Generally consists of a single component) recrystallized in a suitable solvent system.
A single crystal sample suitable for X-ray diffraction can be obtained, and its size is about 05 mm. For example: snowflakes, small particles of table salt, etc. Single crystal is an important material in semiconductor science and technology.
Crystal: Crystals have three characteristics: (1) crystals have a certain geometric shape; (2) The crystal has a fixed melting point; (3) Crystals are anisotropic.
features: A single crystal is a crystal with the same atomic arrangement and the same lattice position. For example: monocrystalline silicon.
Polycrystalline is composed of many small grains with the same arrangement but inconsistent orientation, and is called polycrystalline. For example: commonly used metals.
A single crystal has three characteristics of a crystal.
Polycrystals have the first two characteristics but are isotropic.
features: Polycrystalline.
The whole object is made up of a number of small crystals arranged in a haphazard manner, such an object is called.
Polycrystalline. For example: commonly used metals. The atoms are not arranged according to uniform rules in the whole crystal, and there is no definite shape and physical properties.
Same in all directions.
For example, table salt is made up of many single crystals of table salt stuck together to form large chunks.
Polycrystals have a definite melting point.
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Anonymous users2024-02-07Crystals have fixed melting and freezing points; Amorphous does not have a fixed melting and freezing point;
Both monocrystals and polycrystals belong to crystals, that is, they both have fixed melting and freezing points;
A crystal in which the entire substance is arranged periodically by atoms or molecules according to a certain law is called a single crystal.
The whole object is made up of many small crystals arranged in a haphazard manner, and such an object is called polycrystalline.
That is to say, each grain is a single crystal, and the same grain is regularly arranged to form a single crystal; Conversely, the disordered and chaotic arrangement of the same grain constitutes polycrystalline. For example, a NaCl molecule is a single crystal, and many NaCl molecules are mixed together to form a polycrystal.
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Anonymous users2024-02-06Monocrystalline, polycrystalline, and amorphous are the three forms of compounds, if there is a use, it is to see the three-dimensional configuration of the compound, if it is monocrystalline, polycrystalline then it has a regular geometric configuration, if it is amorphous, it does not have a regular geometric configuration.
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Anonymous users2024-02-05The difference between crystalline, polycrystalline, and amorphous.
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Anonymous users2024-02-041. The spatial structure is different
1) A single crystal is a whole crystal composed of a single grain, or can be used with a spatial lattice pattern to run through the entire crystal. The molecules (atoms or ions) contained in a single crystal sample are in three-dimensional space.
It is a state of solids that is arranged in a regular, periodic manner.
2) Polycrystals are composed of many small grains arranged in the same way but in different directions. For example: commonly used metals. Polycrystals consist of a large number of grains in a single crystal, or cannot be covered by a spatial lattice pattern.
2. The crystal characteristics are different
1) Single crystal has a certain geometric shape; has a fixed melting point; There is anisotropy.
features: 2) Polycrystals have a certain geometric shape; There is a fixed melting point, and polycrystals are isotropic.
features: <>
Crystal characteristics: 1) The crystals formed by natural condensation and without external interference have neat and regular geometric shapes, that is, the self-normity of crystals.
2) The crystal has a fixed melting point, and the temperature crystallinity remains constant during the melting process.
3) Single crystals are anisotropic.
4) Crystals can cause regular diffraction of X-rays.
Whether X-ray diffraction can be produced on a macroscopic scale is the main method for determining whether a substance is a crystal or not.
5) The crystal plane corresponding to the crystal.
The angles are equal and are called conservation of crystal plane angles.
You can take the blue equipment to Norton and disassemble it, and then a colored crystal will be produced. That is, it could be one of the blue, red, white, and black. But there may be a lot of outbreaks. >>>More
Near-body implant surgery is generally chosen only for ultra-high myopia, which is generally above 1025 degrees. 800 degrees is not recommended. In addition, it is best to supplement the eyes with more eye vision nutrients to control the increase in myopia first.
It should cost more than 10,000 yuan, the specific is not very clear, ICL lens implantation is the most advanced method of high myopia, so it is more expensive, but the effect is not bad, and the economy allows it to be used.
There are two types of intraocular lens implantation, ICL lens implantation, which is the best new option for patients with high and ultra-high myopia, and TICL lens implantation, which is a T-optimized correction surgery using TICL lens, which can correct high myopia and astigmatism at the same time.
Purple Sands is certainly not a crystal, and has nothing to do with it. >>>More