What does ac mean?

1, alternating current (alternating current? Current) refers to the current whose magnitude and direction change periodically, which is widely used in power transmission (namely AC power transmission) at present. After michael faraday discovered electromagnetic induction, the principle of alternating current has been revealed. 189 1 year, nikola tesla obtained the patent of "high frequency" (15000 Hz) alternator.

2. Acoustic time difference curve. In porosity logging, acoustic time difference is used to reflect the curve data of lithology and rock structure. Because sound waves can be written as acoustic, AC is used to refer to this data.

3, attenuation coefficient (attenuation? Coefficient), also known as attenuation constant and attenuation coefficient, refers to the change or loss of a certain substance or physical quantity (light, sound, electricity, heat, pollutants in water, etc.). ) under the influence of other physical phenomena (medium density, humidity, temperature, etc.). ) under a unit measurement.

4. Acetate, also known as acetate, is a product formed after the carboxyl proton (H+ hydrogen ion) of acetic acid is replaced by other metal cations, such as sodium acetate (NaAc). Meanwhile, acetic acid itself can also be written as HAc. Acetate, the acid ion of acetate, with the molecular formula of CH3COO- or [C2H3O2]-, belongs to a kind of carboxylate ion.

5. Acetyl is an acyl functional group composed of methyl and carbonyl in organic chemistry. The molecular formula is CH3-C=O-R or CH3C(O)-, which is also commonly called Ac-. The chemical reaction of introducing acetyl groups into molecules with acetylating reagents (such as acetyl chloride or acetic anhydride) is called acetylation.