French chemist and physicist who isolated the element boron(1809) and formulated a law that explains the behavior of a gas under constant pressure. 蓋魯薩克，約瑟夫·路易斯1778－1850法國化學(xué)家和物理學(xué)家，析出硼元素(1809年), 并且確切陳述了解釋氣體在固定壓力下的表現方式的定律
A variable that is given a constant value for a specified application and that may denote the application. 一種為專(zhuān)用應用程序而給定一個(gè)常數值的變量，而且它可以表示該應用程序。
A constant, variable, function name, or expression. 一種常數、變量、函數名或表達式。
A letter or symbol that represents a particular constant or number, known or unknown, and is not programmer-defined. 文字代表一特定常量或數字的可知或未知的字母或符號，非編程者所規定
