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lubrication

(Encyclopedia)lubrication, introduction of a substance between the contact surfaces of moving parts to reduce friction and to dissipate heat. A lubricant may be oil, grease, graphite, or any substance—gas, liquid...

rubber

(Encyclopedia)CE5 Basic molecules in rubber rubber, any solid substance that upon vulcanization becomes elastic; the term includes natural rubber (caoutchouc) and synthetic rubber. The term elastomer is sometim...

Alba, Fernando Álvarez de Toledo, duque de

(Encyclopedia)Alba or Alva, Fernando Álvarez de Toledo, duque de ălˈbə, ălˈvə, Span. both: fārnänˈdō älˈvärāth dā tōlāˈᵺō do͞oˈkā dā älˈvä [key], b. 1507 or 1508, d. 1582, Spanish gener...

intermolecular forces

(Encyclopedia)intermolecular forces, forces that are exerted by molecules on each other and that, in general, affect the macroscopic properties of the material of which the molecules are a part. Such forces may be ...

hassium

(Encyclopedia)hassium hăsˈēəm, häsˈ– [key], artificially produced radioactive chemical element; symbol Hs; at. no. 108; mass number of most stable isotope 277; m.p., b.p., sp. gr., and valence unknown. Situ...

Hoboken, city, United States

(Encyclopedia)Hoboken hōˈbōkən, –bəkən [key], city (2020 pop. 60,419), Hudson co., NE N.J.,...

hardening

(Encyclopedia)hardening, in metallurgy, treatment of metals to increase their resistance to penetration. A metal is harder when it has small grains, which result when the metal is cooled rapidly. Sometimes small ar...

gadolinium

(Encyclopedia)gadolinium gădəlĭnˈēəm [key], metallic chemical element; symbol Gd; at. no. 64; at. wt. 157.25; m.p. 1,312℃; b.p. 3,233℃; sp. gr. 7.898 at 25℃; valence +3. Gadolinium is a malleable, ducti...

gallium

(Encyclopedia)gallium gălˈēəm [key], metallic chemical element; symbol Ga; at. no. 31; at. wt. 69.723; m.p. 29.78℃; b.p. 2,403℃; sp. gr. 5.904 at 29.6℃ (solid), 6.095 at 29.8℃ (liquid); valence +2 or +3...

microelectronics

(Encyclopedia)microelectronics, branch of electronic technology devoted to the design and development of extremely small electronic devices that consume very little electric power. Although the term is sometimes us...