HS code-based risk profiling for exporters

List of the contents of this article:

• 1, Please explain the principle of Pauli incompatibility
• 2, What are the dangers of non-sine periodic waves in the power supply system? How did it come about?
• 3、 What are the reasons for the abnormal waveform of the ignition system?
• 4. LightningA typical system of magnetic wave application

Please explain the Pauli incompatibility principle

1. In an atomic orbit, it can only accommodate up to 2 electrons, and their spin states are opposite. , this principle is called the Pauli principle.

2. The Pauli incompatibility principle refers to the inability of electrons with exactly the same motion state in atoms. It is also known as the Pauli atomic and incompatibility principle. In 1925, by Austrian physicist W. Pauli proposed. It is impossible for an atom to have two electrons in an electron layer, an electron sublayer, an electron cloud stretching direction and a spin direction exactly the same.

3. Pauli incompatibility principle, energy minimum principle, Hunt's rule is as follows: PauliThe principle is that each track (such as 1s track, px in 2p track) can only accommodate at most two electrons with opposite spins. The Pauli incompatibility principle belongs to the modern word, which refers to electrons that cannot accommodate exactly the same state of motion in an atom.

What are the dangers of non-sine periodic waves in the power supply system? How did it come about?

Geating harmonics: The waveform of non-sine current is not completely straight, but produces harmonics on the waveform, which will interfere with the AC circuit and affect the performance and stability of the circuit.

Because the sinusoidal voltage is pressurized on the nonlinear load, the base wave current is distorted to produce harmonics. The main nonlinear loads include UPS, switching power supply, rectifier, frequency converter, inverter, etc.

Harmonics generated in the transmission and distribution process. The power transformer is the main source of harmonics in the transmission and distribution process. Because the design of the transformer needs to consider economy, the magnetization curve of its iron core is in a nonlinear saturation state, so that the magnetization current at work is a spire-shaped waveform, thus generating odd harmonics.

The application of voltage-DC power transmission, the emergence of a large number of nonlinear loads and the nonlinear components in the power supply system itself have made the voltage waveform distortion in the system more and more serious, causing great harm to the power system, such as increasing the component loss in the power supply system and reducing the use of electrical equipment. Service life, interference with the communication system, etc.

In the power system, the root cause of harmonics is caused by nonlinear loads. When the current flows through the load, it is not linearly related to the applied voltage, forming a non-sine current, that is, harmonics are generated in the circuit.

Harmonic component refers to the integer multiple of the number of times greater than 1 in the Fourier series of periodic electrical quantities. The harmonics of the power grid are mainly caused by three aspects: power generation equipment (power supply), power transmission and distribution equipment, and nonlinear load of the power system. Including: (1) Harmonics generated by the power supply.

What are the reasons for the abnormal waveform of the ignition system?

The first oscillation wave is less, indicating that the resistance in the primary circuit is too large. ; The first oscillation wave is large, indicating that the capacity of the primary circuit is too large or the impedance of the secondary circuit of the ignition system is large. ; A small redundant waveform appears before the second oscillation wave, indicating that the conduction condition of the primary circuit is not good enough at the moment of tying, so a small redundant waveform appears.

Among the failures of the ignition system, the main faults are no ignition, lack of fire, random fire, weak fire, and inaccurate ignition.These failures will cause the engine to fail to start or work abnormally. The faulty part of the ignition system can be divided into two parts: low-voltage line and high-voltage line.

Insufficient battery storage; poor wire connection or disorder; poor battery ironing; damaged distributor or Hall sensor; damaged ignition switch or poor wiring; damaged or poor wiring of transistor ignition control unit. Most of the diagnostic methods for low-voltage circuit faults are to check the ammeter or voltmeter line by line to eliminate the fault points.

Low-voltage and high-voltage circuit failures. The sequence of faults that may be encountered in the electronic ignition system include common faults in low-voltage and high-voltage circuits, and insufficient battery storage.

Common faults and causes of ignition system 1 Spark plug failure (1) Fault phenomenon: spark plug carbonization, oil pollution and overheating, etc.Like, (2) Cause of failure: Spark plug carbon: The end of the insulator, electrode and spark plug shell are often covered with a fairly thick layer of black-gray powder-like soft scale.

There is a problem with the ignition system or fuel supply system. After this situation, it is recommended to check the ignition system and fuel supply system. Correctly distinguish between normal sound and abnormal sound.

Typical system of electromagnetic wave application

Communication: Electromagnetic waves such as radio waves and microwaves are widely used in television, radio, mobile communication and other communication fields; optical communication uses visible light or infrared (belonging to electromagnetic radiation) as Information carriers are widely used in home and office LANs, etc.

Radio waves: radar, radio station, television transmission, mobile communication, telegram.

Infrared is used for remote control, thermal imager, infrared guided missile, etc. Visible light is the basis used by all living things to observe things. Ultraviolet rays are used for medical disinfection, verifying counterfeit banknotes, measuring distance, engineering flaw detection, etc. X-rays are used for CT imaging. Gamma rays are used for treatment, causing atoms to jump to produce new rays, etc.

Electromagnetic waves are generated by LC oscillation circuits, which are widely used in communication, radio, radar and other fields. Radar uses electromagnetic waves to send signals to determine the target position after reflection. Radio broadcasting Radio broadcasting uses electromagnetic waves to spread information.

It was found that Maxwell predicted the existence of electromagnetic waves. Hertz proved the existence of electromagnetic waves. 2 The electromagnetic spectrum applied is radio waves, microwaves, infrared rays., visible light, ultraviolet light, Renchen X-ray, gamma-ray first, radio waves are used for communication, etc., microwaves are used for microwaves, infrared rays are used for remote control and other visible light.

Electromagnetic waves are transverse waves, which can be used for detection, positioning, communication, etc. Electromagnetic waves are radio waves, microwaves, infrared rays, visible light, ultraviolet rays, Renchen rays and gamma rays.