The purpose of this dictionary is to provide rapid reference tools for translators, abstractors, and research analysts concerned with scientific and technical materials in Mainland China. This dictionary contains about 28000 terms selected from sources published in Mainland China. The terms included relate not only to general physics, nuclear physics, reactor physics, isotope technology, etc., but incorporate vocabulary from the basic sciences and the auxiliary technologies closely associated with the fields of physics, such as chemistry, engineering, mechanics, mineralogy, etc. The special features of this dictionary are Mainland Chinese practice in regard to: (1) terminology; (2) style of characters; and (3) complete alphabetic lookup by means of the 'pinyin' spelling. Characters in some of the terms have been regrouped for optimum clearness and suitability for computer processing.