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potentiometer

(Encyclopedia)potentiometer. 1 Manually adjustable, variable, electrical resistor. It has a resistance element that is attached to the circuit by three contacts, or terminals. The ends of the resistance element are...

ayahuasca

(Encyclopedia)ayahuasca or yagé, drink made by boiling various South American plants, used for centuries by shamans of traditional societies in the Amazon region in religious and healing ceremonies. It is usually ...

ammonium nitrate

(Encyclopedia)ammonium nitrate, chemical compound, NH4NO3, that exists as colorless, rhombohedral crystals at room temperature but changes to monoclinic crystals when heated above 32℃. It is extremely soluble in ...

isopropanol

(Encyclopedia)isopropanol, isopropyl alcohol, or 2-propanol īˌsəprōˈpənōl, īˌsəprōˈpĭl [key], (CH3)2CHOH, a colorless liquid that is miscible with water. It melts at −89℃ and boils at 82.3℃. It ...

dolomite

(Encyclopedia)dolomite dōˈləmītˌ, dŏlˈə– [key]. 1 Mineral, calcium magnesium carbonate, CaMg (CO3)2. It is commonly crystalline and is white, gray, brown, or reddish in color with a vitreous to pearly lus...

anhydride

(Encyclopedia)anhydride ănhīˈdrīd, –drĭd [key] [Gr.,=without water], chemical compound formed by removing water, H2O, from another compound; the anhydride can also react with water to form the original compo...

Suzuki, Akira

(Encyclopedia)Suzuki, Akira, 1930–, Japanese chemist, Ph.D. Hokkaido Univ., Sapporo, 1959. He was a professor at Hokkaido from 1963 until his retirement in 1994. Since then, he has taught for short periods at Oka...

skin patch

(Encyclopedia)skin patch, transdermal patch, or transdermal delivery system, adhesive patch used to deliver a controlled dose of a drug through the skin over a period of time. A skin patch uses a special membrane ...

agar, substance obtained from seaweed

(Encyclopedia)agar äˈgär, āˈ–, ăgˈär [key], product obtained from several species of red algae, or seaweed, chiefly from the Ceylon, or Jaffna, moss (Gracilaria lichenoides) and species of Gelidium, harve...

pen-based computer

(Encyclopedia)pen-based computer, computer that uses software to enable it to accept handwriting or drawing as a form of input. A stylus, which may contain special electronic circuitry, may be used to write on the ...