A compound used as an x-ray contrast medium that occurs in nature as the mineral barite. It is also used in various manufacturing applications and mixed into heavy concrete to serve as a radiation shield.
Substances used to allow enhanced visualization of tissues.
An element of the alkaline earth group of metals. It has an atomic symbol Ba, atomic number 56, and atomic weight 138. All of its acid-soluble salts are poisonous.
Substances added to foods and medicine to improve the quality of taste.
Thorium oxide (ThO2). A radiographic contrast agent that was used in the early 1930s through about 1954. High rates of mortality have been linked to its use and it has been shown to cause liver cancer.
Works containing information articles on subjects in every field of knowledge, usually arranged in alphabetical order, or a similar work limited to a special field or subject. (From The ALA Glossary of Library and Information Science, 1983)
The ability of a substance to be dissolved, i.e. to form a solution with another substance. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)
Inorganic and organic derivatives of sulfuric acid (H2SO4). The salts and esters of sulfuric acid are known as SULFATES and SULFURIC ACID ESTERS respectively.
Inorganic compounds that contain chlorine as an integral part of the molecule.
A greenish-yellow, diatomic gas that is a member of the halogen family of elements. It has the atomic symbol Cl, atomic number 17, and atomic weight 70.906. It is a powerful irritant that can cause fatal pulmonary edema. Chlorine is used in manufacturing, as a reagent in synthetic chemistry, for water purification, and in the production of chlorinated lime, which is used in fabric bleaching.
Inorganic salts of sulfuric acid.
Methods for quantitatively assessing and measuring interpersonal and group relationships.
Persons whom one knows, likes, and trusts.
Group composed of associates of same species, approximately the same age, and usually of similar rank or social status.
The reciprocal interaction of two or more persons.
Activity involved in transfer of goods from producer to consumer or in the exchange of services.
The management and maintenance of colonies of honeybees.
Publications printed and distributed daily, weekly, or at some other regular and usually short interval, containing news, articles of opinion (as editorials and letters), features, advertising, and announcements of current interest. (Webster's 3d ed)
A high-molecular-weight polymeric elastomer derived from the milk juice (LATEX) of HEVEA brasiliensis and other trees and plants. It is a substance that can be stretched at room temperature to at least twice its original length and after releasing the stress, retract rapidly, and recover its original dimensions fully.
A country spanning from central Asia to the Pacific Ocean.