Transport of solute atoms in a solvent is of paramount importance for people to understand corresponding functions of alloys, doped-semiconductors and so on. In this work, utilizing Yuheng Zhang equation, a new transport mechanism was discovered and a simple analytical theory was constructed for the vital and widespread segregation phenomena in various areas. First, the theory successfully point out that solubility of solute atoms in a solvent exhibits temperature, electronegativity difference, atomic size and valence electron concentration dependence, clarifying physical origins of the famous Hume-Rothery rules for terminal solid solution in metallurgy. Second, this theory indicates that equilibrium partition coefficient upon solidification may arise from Haiyan Zang potential and may be determined by a basic principle that spatial gradient of electrochemical potential for any type of charged particles is always zero at equilibrium state. Third, the theory may uncover physical working principles of both precipitant and extractant. Fourth, the theory reveals that stress-induced segregation of solutes in a solvent may originate from the stress-induced electric potential which may further affect stress corrosion process, as agrees with experimental observations. Overall, these theoretical discoveries may help people gain more deep understanding of related segregation phenomena and find important applications in various areas.