Talking about the phenomenon of static electricity
Static electricity(Static Electricity) is a static electric charge, an objective natural phenomenon, produced in many ways, such as contact, friction, induction between electrical appliances, rush current, etc. The basic process of its production can be summarized as: contact → charge → transfer → even electric layer formation → charge separation.
Matter is composed of molecules, which are composed of atoms, and atoms are composed of negatively charged electrons and positively charged protons. Under normal conditions, the number of protons and electrons of an atom are the same, and the positive and negative balances are balanced, so it appears uncharged to the outside. However, the electrons surround the nucleus and depart from the orbit by external force, leave the original atom A and invade other atoms B. The phenomenon that A atoms are positively charged due to lack of electrons is called a cation. It is a negatively charged phenomenon, called anion. When the electron transfer lacks or too many electrons can create an electric field, this electric field is static electricity. The amount of electrostatic field generated depends on the friction or separation of the substance, the amount of friction or separation, and the relative humidity of the surrounding environment. The reason for the unbalanced electron distribution is that the electrons depart from the orbit by an external force. This external force contains various energies (such as kinetic energy, potential energy, thermal energy, chemical energy, etc.).
Materials that easily transfer electrons (or charges) between atoms are called conductors, and those that cannot transfer electrons (or charges) are called insulators. Both conductors and insulators can be charged under the action of static electricity. Usually most static electricity is caused by friction and separation. Friction causes heat to activate the molecules inside the material. Then the two substances are separated, and the transfer of electrons from one substance to the other may occur. Static electricity has the characteristics of high voltage, low power, low current and short action time.
The static leakage is slow because the resistivity of the materials accumulating static electricity is very high, which causes the static leakage on it to be very slow. The generation and accumulation of static electricity are affected by factors such as materials, impurities, material characteristics, process equipment (such as geometry, contact area) and process parameters (such as operating speed), humidity and temperature, and electrification history.
Static electricity is ubiquitous in daily life. The human body's own actions or contact, separation, friction or induction with other objects can generate thousands of volts or even tens of thousands of volts of static electricity on the human body. For example, when people walk through chemical fiber carpets, they can generate about 35,000V of static electricity; flipping through the plastic manual can generate about 7000V of static electricity. Usually when a piece of plastic film is peeled from an object, it is a typical "contact separation" electrification, and the static electricity generated by taking off clothes in daily life is also "contact separation" electrification.
Solids, liquids and even gases will be electrostatically charged due to contact separation. This is because gas is also composed of molecules and atoms. When air flows, molecules and atoms will also "contact and separate" and become electrified. Solid static up to 20*104Above V, liquid static electricity and powder static electricity can reach tens of thousands of volts, and gas and vapor static electricity can reach more than 1000OV.
The essence of triboelectricity is a process of contact and separation resulting in an imbalance of positive and negative charges. Friction is a process of constant contact andThe process of separation. Therefore, friction electrification is essentially contact separation electrification. In daily life, all kinds of objects may beStatic electricity is generated by movement or friction. Another common type of electrification is induction electrification. When a charged object is close to an uncharged object, it willBoth ends of the charged conductor induce negative and positive electricity respectively.
In the dry and windy autumn, in daily life, we often encounter this phenomenon: before going to bed at night, turn off the light, take off the blended sweater (or wool nitrile pullover) in the dark, you will see flickering Sparks were accompanied by a "crack" sound. When people meet and shake hands, they will suddenly feel the needle tingling as soon as their fingers touch each other; when they wake up and comb their hair in the morning, their hair will often "float" and become more messy; when you pull door handles or turn on the tap, you will get an electric shock. , Often make a "pop, pop" sound, this is the static electricity that occurs in the human body. The above-mentioned phenomena are the result of the external "discharge" of static electricity in the human body.
When the human body is moving, the friction between the skin and clothes and between clothes and clothes will generate static electricity. With the increase of household appliances and the chemical fiber clothes people wear in winter, the static charge generated by household appliances will be absorbed by the human body and accumulated. In addition, the walls and floors in the living room are mostly insulators, and the air is dry, so they are more susceptible to static electricity.
Static electricity is the result of the loss of balance between positive and negative charges in a local area. It is a kind of electrical energy that remains on the surface of an object. In an environment without anti-static treatment, the relationship between the intensity of static electricity and humidity generated in people's daily work and life is shown below surface.
It can be seen from the above table that increasing the humidity of the working environment can reduce the electrostatic voltage. The main measures of static control include: static leakage and dissipation, static neutralization, static shielding and grounding, and humidification.
