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Abstract  

This study characterized the removal of strontium from an aqueous solution via co-precipitation followed by microfiltration (CPMF) on a lab-scale. Sodium carbonate was used as the precipitating agent. Ferric chloride was added to a settler at a dosage of 20 mg/L to improve strontium removal, and it was added to a membrane separator at a dosage of 10 mg/L to reduce membrane fouling. The concentration of strontium in the raw water used in this study was about 5 mg/L. In two intermittent tests, where dosages of sodium carbonate were 2000 mg/L and 1000 mg/L, the mean decontamination factors (DFs) were 237 and 158 and the mean concentration factors (CFs) were 288 and 462, respectively. Although the mean DF value was lower when the sodium carbonate dosage was 1000 mg/L instead of 2000 mg/L, the rate at which the specific flux (SF) of the membrane declined decreased as the amount of the effluent treated increased. The problem of strontium release at the beginning of the operation was controlled by a continuous test in which the dosage of sodium carbonate still was 1000 mg/L and the other parameters were the same as in the other tests. The results showed that the mean DF and CF were 157 and 480, respectively.

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Abstract  

The liquid-liquid extraction behavior of octyldodecylsulfoxide (ODoSO) towards uranium(VI), contained in nitric acid aqueous solution, has been investigated. It was found that the extraction increased with increasing nitric acid concentration up to 2.0 mol/l and then decreased. Extraction also increases with increasing extractant concentration. The extracted species appears to be UO2(NO3)2 .2ODoSO. The influences of temperature, sodium nitrate and oxalate concentrations on the extraction were also investigated and the thermodynamic functions of the extraction reaction were obtained.

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Journal of Radioanalytical and Nuclear Chemistry
Authors:
Jun Tang
,
Gengmei Xing
,
Hui Yuan
,
Xingfa Gao
,
Long Jing
,
Shukuan Wang
,
Yue Cheng
, and
Yuliang Zhao

Abstract  

The electronic properties of the metal atoms encaged in a fullerence cage were investigated using synchrotron X-ray photoelectron spectroscopy. Systematic variations in photoemission of valence band of Gd@C82, Gd@C82(OH)12, and Gd@C82(OH)22 were observed in Gd 5p levels. The results suggest that the electronic properties of the inner metal atom can be efficiently modulated by surface chemistry of the fullerene cage.

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Abstract  

The liquid-liquid extraction behavior of uranium(VI) from aqueous nitric acid with bis(octylsulfinyl)ethane (BOSE) in 1,1,2,2-tetrachloroethane has been studied over a wide range of conditions. The extracted species appears to be UO2(NO3)2·2BOSE. It was found that the extraction increases with increasing nitric acid concentration up to 7 mol/l and then decreased. Extraction also increases with increasing extractant concentration. The influence of temperature and salting-out agent concentration on the extraction equilibrium and stripping of uranium(VI) was also investigated and the enthalpy of the extraction reaction was obtained.

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Journal of Thermal Analysis and Calorimetry
Authors:
Cheng-Li Jiao
,
Li-Fang Song
,
Chun-Hong Jiang
,
Jian Zhang
,
Xiao-Liang Si
,
Shu-Jun Qiu
,
Shuang Wang
,
Li-Xian Sun
,
Fen Xu
,
Fen Li
, and
Ji-Jun Zhao

Abstract

The low-temperature molar heat capacity of crystalline Mn3(HEDTA)2·10H2O was measured by temperature-modulated differential scanning calorimetry (TMDSC) for the first time. The thermodynamic parameters such as entropy and enthalpy relative to 298.15 K were calculated based on the above molar heat capacity data. The compound was characterized by powder XRD, FT-IR spectrum. Moreover, the thermal decomposition characteristics of Mn3(HEDTA)2·10H2O were investigated by thermogravimetry–mass spectrometer (TG–MS). The experimental result through TG measurement shows that a three-step mass loss process exists. H2O, CO2, NO, and NO2 were observed as products for oxidative degradation of Mn3(HEDTA)2·10H2O from the MS curves.

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Abstract

A rapid and simple method for the determination of stearic acid and 12-hydroxystearic acid in PEG-60 hydrogenated castor oil by high performance liquid chromatography with evaporative light scattering detection was established. The oil sample was first pretreated by alkaline hydrolysis. The analysis was performed on a Zhongpu Develop XD-C18 column (250 mm × 4.6 mm, 5 µm) with gradient elution of methanol and 1% acetic acid aqueous solution at a flow rate of 1.2 mL·min−1 and a column temperature of 40 °C. The drift tube temperature of the evaporative light scattering detection system was set at 40 °C, and the pressure of carrier gas (N2) was 337 kPa. The regression equation revealed a good linear relation (r = 0.9993–0.9995) during the test ranges (119.1–1190.7 μg·mL−1 for 12-hydroxystearic acid, 10.7–107.4 μg·mL−1 for stearic acid). The detection limits of 12-hydroxystearic acid and stearic acid were 1.1 and 2.5 μg·mL−1, the limits of quantitation were 3.2 and 7.4 μg·mL−1, respectively. And the mean recoveries were 101.5 and 101.0%, the corresponding relative standard deviations (RSDs) were 2.1 and 2.8%, respectively. The RSDs corresponding to repeatability (n = 6) were both less than 1.7% in terms of precision. As to the stability, the test results remained stable after 8 h at room temperature (RSDs were both less than 2.6%). The developed method showed high sensitivity, recovery, repeatability and stability, which indicated that the method could be applied as a quality evaluation method for the determination of stearic acid and 12-hydroxyoctadecanoic acid in PEG-60 hydrogenated castor oil.

Open access
Journal of Radioanalytical and Nuclear Chemistry
Authors:
Yan Chen
,
Zhi-yuan Chang
,
Yong-gang Zhao
,
Ji-long Zhang
,
Jing-huai Li
, and
Fu-jun Shu

Abstract  

An isotope dilution multicollector inductive coupled plasma mass spectrometry (ID-MC-ICP-MS) method for determining age of trace Pu through measuring 241Pu/241Am, 240Pu/236U ratio was established. At the same time, other two methods-α-spectrometry combined with MC-ICP-MS and liquid scintillator combined with α-spectrometry through measuring 241Pu/241Am ratio to determine the age of trace Pu were also studied. The techniques were explored for the age determination of nanogram grade Pu sample on the basis of Pu/Am, Pu/U separation. The ages of two Pu samples—one with known and the other with unknown age—were determined by the three methods. The determined ages by the three methods were all in agreement with the reference value. The established methods for determining the age of trace Pu could be adopted in the verification activities of nuclear safeguards and nuclear arms control.

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Journal of Radioanalytical and Nuclear Chemistry
Authors:
Wenbin Cao
,
Xingfa Gao
,
Li Qu
,
Zhenlin Chen
,
Genmei Xing
,
Jun Tang
,
Huan Meng
,
Zhen Chen
, and
Yuliang Zhao

Abstract  

It was found that Sc2@C84 or Sc2O3 could be “kicked” into the cavities of single wall carbon nanotubes (SWNTs) by reactor neutrons. Neutron irradiation also efficiently induces coalescing reactions between two fullerene cages with an atom-spacer, forming a C2m =C=C2n type of carbon nanomaterials. This process provides a new subject of studying interactions (and their consequences) of neutrons with nanoparticles, which may put new insights for neutron sciences.

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JPC - Journal of Planar Chromatography - Modern TLC
Authors:
Kit-leong Cheong
,
Ding-tao Wu
,
De-jun Hu
,
Jing Zhao
,
Kai-yue Cao
,
Chun-feng Qiao
,
Bang-xing Han
, and
Shao-ping Li

Multiple species of ginseng are well-known Chinese medicinal herbs. The glycome of Panax species has various beneficial effects; however, studies related to their systematic profiling are very limited. Therefore, the systematic profiling of the glycome of Panax species was investigated in this study. The sugars from different locations and different species of Panax (Panax ginseng, Panax quinquefolium, and Panax notoginseng) were prepared by microwave-assisted extraction. Free mono- and oligo-saccharides were identified by high-performance thin-layer chromatography (HPTLC). Furthermore, polysaccharides were compared and characterized by using saccharide mapping based on HPTLC analysis. The results showed that the mono- and oligo-saccharide in Panax species were similar, including the glucan and pectin type of polysaccharides in different locations and different species of Panax, respectively. The data are helpful to better understand the glycome of different species of Panax and may contribute to rational usage of polysaccharides from Panax species.

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Abstract

Atractylodis macrocephalae rhizome (AMR) belongs to medicine food homology. Its' clinical application of invigorating the spleen-stomach of AMR was applied to various diseases. In this research, a UPLC-QTOF-MS method was developed for qualitative and quantitative analysis of AMR, simultaneously. A Waters Acquity BEH C18 column (2.1 mm × 100 mm, 1.7 μm particle size) was used for separation of AMR multi-components. The column was eluted with a mobile phase of 0.1% formic acid-water and 0.1% formic acid-acetonitrile. Electron spray ionization with positive-ion mode and external standard method was utilized for quantifying the nine analytes in AMR. Constituents of AMR were scanned by UPLC-QTOF-MS and then identified by mass fragments and chromatographic information compared with the published literature and reference standards. Under positive mode, a total of 61 chemical compositions including 16 terpenoids, 8 polyacetylenes, 6 aromatics, 5 flavonoids, 5 coumarins, 5 organic acids, 4 amino acids, 3 fatty acids, 3 aliphatics, 2 steroids, and 2 alkenes, a nucleoside and an aldehyde were identified. Simultaneously, the contents of three amino acids (L-tyrosine, L-phenylalanine, and L-tryptophan), three sesquiterpenoids (atractylenolide Ⅲ, atractylenolide Ⅱ, and atractylenolide Ⅰ), a flavonoid (rutin), an organic acid (ferulic acid), and a pentacyclic triterpenoid (oleanolic acid) were determined in seventeen AMR batches. Amino acids and triterpenoid were quantified for the first time in AMR. The UPLC-QTOF-MS method developed in this article was reliable, practical, and useful for qualitative and quantitative evaluation of AMR multi-components.

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