Authors:X. Liu, H. Zhang, Z. Tan, K. Han, and L. Sun
The isoquinoline alkaloids were isolated from traditional Chinese drugs of Phellodendri Cortex, Radix Stephaniae Tetrandrae,
Corydalis Yanhusuo and Corydalis Bungeana. The power-time curves of growth of E. coli at different concentrations of isoquinoline alkaloid at 37�C were determined by a 2277 Thermal Activity Monitor. The rate
constant of bacteriostastic activity was calculated. The relationship between growth rate constant and concentration was established.
The optimum bacteriostastic concentration was determined. Experimental results have indicated that all the isoquinoline alkaloids
isolated from the four kinds of traditional Chinese drugs have bacteriostastic activity and the order is Phellodendri Cortex>Radix
Stephaniae Tetrandrae>Corydalis Yanhusuo>Corydalis Bungeana.
Authors:Yingjie Li, Rongyue Sun, Jianli Zhao, Kuihua Han, and Chunmei Lu
The calcination characteristics, sulfation conversion, and sulfation kinetics of a white mud from paper manufacture at fluidized bed combustion temperatures were investigated in a thermogravimetric analyzer. Also, the comparison between the white mud and the limestone in sulfation behavior and microstructure was made. Although the white mud and the limestone both contain lots of CaCO3, they are different in the alkali metal ions content and microstructure. It results in a marked difference in sulfation behavior between the white mud and the limestone. The CaO derived from white mud achieves the maximum sulfation conversion of 83% at about 940 °C which is 1.7 times higher than that derived from limestone at about 880 °C. The shrinking unreacted core model is appropriate to analyze the sulfation kinetics of the white mud. The chemical reaction activation energy Ea and the activation energy for product layer diffusion Ep for the sulfation of the white mud are 44.94 and 55.61 kJ mol−1, respectively. Ep for the limestone is 2.8 times greater than that for the white mud. The calcined white mud possesses higher surface area than the calcined limestone. Moreover, the calcined white mud has more abundant pores in 4–24 nm range which is almost optimum pore size for sulfation. It indicates that the microstructure of the white mud is beneficial for SO2 removal.
Authors:Guo-Xin Sun, Jing-Tian Han, Bo-Rong Bao, and Si-Xiu Sun
N,N-dialkylamides having ethyl (DEDOA), butyl (DBDOA) and octyl (DODOA) groups as the alkyl substituents were synthesized
in order to investigate their selectivity and capability in the extraction from acidic nitrate media in nuclear reprocessing.
The extraction distribution coefficients of U(VI) with the amides in toluene decrease in the order of DODOA>DBDOA>DEDOA. The
structure of the extracted species was suggested from the dependence of the distribution ratio on the concentration of the
extractant, with the aid of FT-IR spectra. The structural effect on the extraction capability of U(VI) was discussed in terms
of the molecular modelling. The effects of temperature on the distribution ratios were also considered, and the extraction
reaction enthalpy was calculated.
Authors:Shao Hua, Han Jing-Tian, Sun Guo-Xin, Bao Bo-Rong, and Sun Si-Xiu
The extraction of uranium(VI) from nitric acid by N-octanoylpiperidine (OPPD) in toluene has been investigated at varying concentrations of nitric acid, extractant, salting-out agent LiNO3 and at different temperatures. The mechanism of extraction is discussed in the light of the results obtained. The extracted species have also been investigated using FT-IR spectrometry. The related thermodynamic functions were calculated.
Authors:Hua Shao, Jing-Tian Han, Guo-Xin Sun, Bo-Rong Bao, Yong-Hui Yang, and Si-Xiu Sun
The extraction performance of uranium(VI) from nitric acid with N-octanoylpiperidine (OPPD) in series of diluents has been investigated. The dependence of extraction distribution on the concentrations of aqueous nitric acid and OPPD and also the temperature has been studied. The experimental results showed that the decreasing order of extraction ability of OPPD is as follows: benzene, dimethyl benzene (DMB), toluene, 1,2-dichloroethene, n-octane, carbon tetrachloride, cyclohexane, chloroform. It cannot be interpreted only on the basis of polarity of the diluents. The interaction between extractant or extracted species and diluent is discussed.
Authors:Han Jing-Tian, Sun Guo-Xin, Fang Jian-Hui, and Bao Bo-Rong
The extraction of uranium (VI) from nitric acid by N-octanoylpyrrolidine (OPOD) in toluene has been investigated at varying
concentrations of nitric acid, extractant, salting-out agent LiNO3 and at different temperatures. The mechanism of extraction is discussed in the light of the obtained results.
Authors:Sun Guo-Xin, Cui Yu, Han Jing-Tian, Shao Hua, and Bao Bo-Rong
The extraction of U(VI) from nitric acid solutions with di-(1-methylheptyl) phosphoric acid has been investigated. The dependence on nitric acid concentration, DMHPA concentration and temperature has been considered and the infra-red spectra of extracted species and extractant were recorded. The mechanism of extraction is discussed in the light of the results obtained.
Authors:Han Jing-Tian, Sun Guo-Xin, Shao Hua, Chen Shu-Feng, and Bao Bo-Rong
A new bifunctional extractant named phenyl-N,N-dibutylcarbamoylmethyl sulfoxide (PCMSO) is synthesized and characterized in
order to investigate its selectivity and capability in the extraction from acidic nitrate media in nuclear reprocessing. The
extraction of uranium (VI) with PCMSO in toluene has been studied at various concentrations of nitric acid, extractant and
salting-out agent (LiNO3). The mechanism of extraction is discussed in the light of the results obtained. The extracted species has also been investigated
using FT-IR spectrometry. The related thermodynamic functions were calculated. The IR spectral study was also made of the
Authors:Yang Yan-Zhao, Liu Wen-Tao, Han Jian, Zeng Shan, and Sun Si-Xiu
The kinetics and mechanism of uranium(VI) extraction from nitric acid solution by bis(octylsulfinyl)methane (BOSM) are studied
with the method of stationary interface cell. The effects of temperature, extractant and nitric acid concentrations are discussed.
The results showed that the extraction process is controlled by the following reaction: UO2(NO3)2 + BOSM(i)⇄k1k-1UO2(NO3)2BOSM(i). The variation of enthalpy associated with the extraction is -22.1±2.1 kJ/mol.
Authors:Chang Lee, Myung Lee, Sun Han, Yeoung-Keong Ha, and Kyuseok-Song
A simple and rapid separation procedure was systemized for the determination of 99Tc, 90Sr, 94Nb, 55Fe and 59,63Ni in low and intermediate level radioactive wastes. The integrated procedure involves precipitation, anion exchange and extraction
chromatography for the separation and purification of individual radionuclide from sample matrix elements and from other radionuclides.
After separating Re (as a surrogate of 99Tc) on an anion change resin column, Sr, Nb, Fe and Ni were sequentially separated as follows; Sr was separated as Sr (Ca-oxalate)
co-precipitates from Nb, Fe and Ni followed by purification using Sr-Spec extraction chromatographic resin. Nb was separated
from Fe and Ni by anion exchange chromatography. Fe was separated from Ni by anion exchange chromatography. Ni was separated
as Ni-dimethylglyoxime precipitates after the removal of 134,137Cs and 110mAg by Cs-phosphotungstate and AgCl precipitation, respectively. Finally, the radionuclide sources were prepared by precipitation
for their radioactivity measurements. The reliability of the procedure was evaluated by measuring the recovery of chemical
carriers added to a synthetic radioactive waste solution.