“ion exchange”的概念、定义、翻译、参考文献-科学参考

ion exchange

Physics

The exchange of ions of the same charge between a solution (usually aqueous) and a solid in contact with it. The process occurs widely in nature, especially in the absorption and retention of water-soluble fertilizers by soil. For example, if a potassium salt is dissolved in water and applied to soil, potassium ions are absorbed by the soil and sodium and calcium ions are released from it.

The soil, in this case, is acting as an ion exchanger. Synthetic ion-exchange resins consist of various copolymers having a cross-linked three-dimensional structure to which ionic groups have been attached. An anionic resin has negative ions built into its structure and therefore exchanges positive ions. A cationic resin has positive ions built in and exchanges negative ions. Ion-exchange resins, which are used in sugar refining to remove salts, are synthetic organic polymers containing side groups that can be ionized. In anion exchange, the side groups are ionized basic groups, such as −NH₃⁺ to which anions X⁻ are attached. The exchange reaction is one in which different anions in the solution displace the X⁻ from the solid. Similarly, cation exchange occurs with resins that have ionized acidic side groups such as −COO⁻ or −SO₂O⁻, with positive ions M⁺ attached.

Ion exchange also occurs with inorganic polymers such as zeolites, in which positive ions are held at sites in the silicate lattice. These are used for water-softening, in which Ca²⁺ ions in solution displace Na⁺ ions in the zeolite. The zeolite can be regenerated with sodium chloride solution. Ion-exchange membranes are used as separators in electrolytic cells to remove salts from sea water and in producing deionized water. Ion-exchange resins are also used as the stationary phase in ion-exchange chromatography.

Chemistry

The exchange of ions of the same charge between a solution (usually aqueous) and a solid in contact with it. The process occurs widely in nature, especially in the absorption and retention of water-soluble fertilizers by soil. For example, if a potassium salt is dissolved in water and applied to soil, potassium ions are absorbed by the soil and sodium and calcium ions are released from it.
The soil, in this case, is acting as an ion exchanger. Synthetic ion-exchange resins consist of various copolymers having a cross-linked three-dimensional structure to which ionic groups have been attached. An anionic resin has negative ions built into its structure and therefore exchanges positive ions. A cationic resin has positive ions built in and exchanges negative ions. Ion-exchange resins, which are used in sugar refining to remove salts, are synthetic organic polymers containing side groups that can be ionized. In anion exchange, the side groups are ionized basic groups, such as –NH₃⁺ to which anions X⁻ are attached. The exchange reaction is one in which different anions in the solution displace the X⁻ from the solid. Similarly, cation exchange occurs with resins that have ionized acidic side groups such as –COO⁻ or –SO₂O⁻, with positive ions M⁺ attached.
Ion exchange also occurs with inorganic polymers such as zeolites, in which positive ions are held at sites in the silicate lattice. These are used for water-softening, in which Ca²⁺ ions in solution displace Na⁺ ions in the zeolite. The zeolite can be regenerated with sodium chloride solution. Ion-exchange membranes are used as separators in electrolytic cells to remove salts from sea water and in producing deionized water. Ion-exchange resins are also used as the stationary phase in ion-exchange chromatography.

Chemical Engineering

The process involving the adsorption of ions in a solution on a surface of particles or gels accompanied by the simultaneous desorption of ions of like charge. An ion exchange resin is a synthetic polymeric resin that is able to exchange ions on the surface of a polymeric molecular network that possesses functional groups that carry an ionic charge. The extent of the exchange is dependent on the nature of the resin and the type of exchanging ions. Ion exchange is used in water treatment to remove calcium and magnesium ions, and replace them with soluble sodium ions. Ion exchange equipment consists of a fixed bed of the resin down through which the water for ion exchange passes. The ion exchange resin may be naturally occurring such as zeolites, aluminosilicates, or synthetic such as cross-linked polystyrene.

Biology

The exchange of ions of the same charge between a solution (usually aqueous) and a solid in contact with it. The process occurs widely in nature, especially in the absorption and retention of water-soluble fertilizers by soil. For example, if a potassium salt is dissolved in water and applied to soil, potassium ions are absorbed by the soil and sodium and calcium ions are released from it. The soil, in this case, is acting as an ion exchanger. Synthetic ion-exchange resins consist of various copolymers having a cross-linked three-dimensional structure to which ionic groups have been attached. An anionic resin has negative ions built into its structure and therefore exchanges positive ions. A cationic resin has positive ions built in and exchanges negative ions. Ion-exchange resins are used as the stationary phase in ion-exchange chromatography.

Geology and Earth Sciences

Reversible exchange of ions in a crystal for other ions in solution, without disturbance of the crystal lattice or its electrical neutrality. This occurs by diffusion, particularly in crystals where weakly bonded ions form one- or two-dimensional channelways. Natural zeolites are used to capture anions and cations from solution. Artificial ion-exchange resins with three-dimensional hydrocarbon networks are commonly used (e.g. in water softeners; for separating isotopes; in desalination; and in the chemical extraction of elements from ores).

单词	ion exchange
释义	ion exchange Physics The exchange of ions of the same charge between a solution (usually aqueous) and a solid in contact with it. The process occurs widely in nature, especially in the absorption and retention of water-soluble fertilizers by soil. For example, if a potassium salt is dissolved in water and applied to soil, potassium ions are absorbed by the soil and sodium and calcium ions are released from it. The soil, in this case, is acting as an ion exchanger. Synthetic ion-exchange resins consist of various copolymers having a cross-linked three-dimensional structure to which ionic groups have been attached. An anionic resin has negative ions built into its structure and therefore exchanges positive ions. A cationic resin has positive ions built in and exchanges negative ions. Ion-exchange resins, which are used in sugar refining to remove salts, are synthetic organic polymers containing side groups that can be ionized. In anion exchange, the side groups are ionized basic groups, such as −NH₃⁺ to which anions X⁻ are attached. The exchange reaction is one in which different anions in the solution displace the X⁻ from the solid. Similarly, cation exchange occurs with resins that have ionized acidic side groups such as −COO⁻ or −SO₂O⁻, with positive ions M⁺ attached. Ion exchange also occurs with inorganic polymers such as zeolites, in which positive ions are held at sites in the silicate lattice. These are used for water-softening, in which Ca²⁺ ions in solution displace Na⁺ ions in the zeolite. The zeolite can be regenerated with sodium chloride solution. Ion-exchange membranes are used as separators in electrolytic cells to remove salts from sea water and in producing deionized water. Ion-exchange resins are also used as the stationary phase in ion-exchange chromatography. Chemistry The exchange of ions of the same charge between a solution (usually aqueous) and a solid in contact with it. The process occurs widely in nature, especially in the absorption and retention of water-soluble fertilizers by soil. For example, if a potassium salt is dissolved in water and applied to soil, potassium ions are absorbed by the soil and sodium and calcium ions are released from it. The soil, in this case, is acting as an ion exchanger. Synthetic ion-exchange resins consist of various copolymers having a cross-linked three-dimensional structure to which ionic groups have been attached. An anionic resin has negative ions built into its structure and therefore exchanges positive ions. A cationic resin has positive ions built in and exchanges negative ions. Ion-exchange resins, which are used in sugar refining to remove salts, are synthetic organic polymers containing side groups that can be ionized. In anion exchange, the side groups are ionized basic groups, such as –NH₃⁺ to which anions X⁻ are attached. The exchange reaction is one in which different anions in the solution displace the X⁻ from the solid. Similarly, cation exchange occurs with resins that have ionized acidic side groups such as –COO⁻ or –SO₂O⁻, with positive ions M⁺ attached. Ion exchange also occurs with inorganic polymers such as zeolites, in which positive ions are held at sites in the silicate lattice. These are used for water-softening, in which Ca²⁺ ions in solution displace Na⁺ ions in the zeolite. The zeolite can be regenerated with sodium chloride solution. Ion-exchange membranes are used as separators in electrolytic cells to remove salts from sea water and in producing deionized water. Ion-exchange resins are also used as the stationary phase in ion-exchange chromatography. Chemical Engineering The process involving the adsorption of ions in a solution on a surface of particles or gels accompanied by the simultaneous desorption of ions of like charge. An ion exchange resin is a synthetic polymeric resin that is able to exchange ions on the surface of a polymeric molecular network that possesses functional groups that carry an ionic charge. The extent of the exchange is dependent on the nature of the resin and the type of exchanging ions. Ion exchange is used in water treatment to remove calcium and magnesium ions, and replace them with soluble sodium ions. Ion exchange equipment consists of a fixed bed of the resin down through which the water for ion exchange passes. The ion exchange resin may be naturally occurring such as zeolites, aluminosilicates, or synthetic such as cross-linked polystyrene. Biology The exchange of ions of the same charge between a solution (usually aqueous) and a solid in contact with it. The process occurs widely in nature, especially in the absorption and retention of water-soluble fertilizers by soil. For example, if a potassium salt is dissolved in water and applied to soil, potassium ions are absorbed by the soil and sodium and calcium ions are released from it. The soil, in this case, is acting as an ion exchanger. Synthetic ion-exchange resins consist of various copolymers having a cross-linked three-dimensional structure to which ionic groups have been attached. An anionic resin has negative ions built into its structure and therefore exchanges positive ions. A cationic resin has positive ions built in and exchanges negative ions. Ion-exchange resins are used as the stationary phase in ion-exchange chromatography. Geology and Earth Sciences Reversible exchange of ions in a crystal for other ions in solution, without disturbance of the crystal lattice or its electrical neutrality. This occurs by diffusion, particularly in crystals where weakly bonded ions form one- or two-dimensional channelways. Natural zeolites are used to capture anions and cations from solution. Artificial ion-exchange resins with three-dimensional hydrocarbon networks are commonly used (e.g. in water softeners; for separating isotopes; in desalination; and in the chemical extraction of elements from ores).
随便看	guided missile guidepost cell guider guide star guide telescope guideword Guidoni, Umberto (1954– ) guild guild((in ecology)) Guillaume, Charles Edouard Guillemin effect Guillemin line Guillemin, Roger guillemot guillotine guilt/shame guiltware Guinea Guinea-Bissau Guinea current guineafowl guinea pig Guiscard, Robert (1015–85) Guise Guizot, François Pierre Guillaume (1787–1874)