Li Yulan

Thermodynamics of the Extraction of U(VI) by N,N′-Didecanoylpiperazine

A novel extractant, N, N′-didecanoylpiperazine (DDPEZ), was synthesized for the first time. The extraction of U(VI) by DDPEZ from aqueous nitric acid media in carbon tetrachloride has been studied. The dependence of extraction distribution ratio on concentration of aqueous nitric acid, extractant, salting-out agent and temperature was investigated and the enthalpy of the extraction was calculated.

Spectral line identification of Comet Halley in March–April 1986

Abstract In March–April 1986 when Comet Halley was between 1 and 1.5 AU fron the Sun, we used the 1-metre telescope of Yunnan Observatory and obtained 7 long-slit spectra at a dispersion of 165 A/mm and with a resolution better than 7 A. The results of line identification on 6 of the plates between 3000–5100 A are given here. The main lines are emission lines of the molecules CN, C2, C3, CH, NH, and OH, while NH2, CH+, N and H2CO lines are probably present also. The appearance of the OH (3090 A) line shows incidentally that conditions at Yunnan Observatory are favorable for ultraviolet observations.