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solder

(Encyclopedia)solder sŏdˈər [key], metal alloy used in the molten state as a metallic binder. The type of solder to be used is determined by the metals to be united. Soft solders are commonly composed of lead an...

silver nitrate

(Encyclopedia)silver nitrate nīˈtrāt [key], chemical compound, AgNO3, a colorless crystalline material that is very soluble in water. The most important compound of silver, it is used in the preparation of silve...

potassium nitrate

(Encyclopedia)potassium nitrate, chemical compound, KNO3, occurring as colorless, prismatic crystals or as a white powder; it is found pure in nature as the mineral saltpeter, or niter. (The name saltpeter is also ...

nitrogen

(Encyclopedia)nitrogen nīˈtrəjən [key], gaseous chemical element; symbol N; at. no. 7; interval in which at. wt. ranges 14.00643–14.00728; m.p. −209.86℃; b.p. −195.8℃; density 1.25 grams per liter at ...

disinfectant

(Encyclopedia)disinfectant, agent that destroys disease-causing microorganisms and their spores. Disinfectants, or germicides, are sometimes considered to be substances applied to inanimate bodies, whereas antisept...

clubroot

(Encyclopedia)clubroot, disease of cabbages, turnips, radishes, and other plants belonging to the family Cruciferae (or Brassicaceae; mustard family). It is induced by a plasmodial slime mold that attacks the roots...

ferrous sulfate

(Encyclopedia)ferrous sulfate or iron (II) sulfate, chemical compound, FeSO4. It is known as the monohydrate, FeSO4·H2O; the tetrahydrate, FeSO4·4H2O; the pentahydrate, FeSO4·5H2O; and the heptahydrate, FeSO4·7...

Huaynaputina

(Encyclopedia)Huaynaputina, volcano, 15,912 ft (4,850 m) high, Moquegua region, S Peru, in the central Andes. A stratovolcano, it lies on the W rim of the Río Tambo canyon and has several ash cones within its crat...

Holley, Robert William

(Encyclopedia)Holley, Robert William, 1922–93, American biochemist, b. Urbana, Ill., Ph.D. Cornell, 1947. He was a professor at Cornell (1948–68) before he joined (1968) the Salk Institute, and he continued an ...

Anfinsen, Christian Boehmer

(Encyclopedia)Anfinsen, Christian Boehmer, 1916–95, American biochemist, b. Monessen, Pa., Ph.D. Harvard Medical School, 1943. He spent the early years of his career in brief research and fellowship positions at ...