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  • Author or Editor: Yan Sun x
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Abstract  

The liquid-liquid extraction of uranium(VI) from aqueous nitric acid with n-octyldecylsulfoxide (ODSO) in toluene has been studied over a wide range of conditions. The extracted species appears to be UO2(NO3)2·2ODSO. The extraction increased with increasing nitric acid concentration up to 2.0 mol/l and then decreased. Extraction also increased with increasing extractant concentration. The influence of temperature, salting-out agent concentration and complex anion concentration on the extraction equilibrium were also investigated, and the enthalpy of the extraction reaction was calculated.

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Authors: L. Wang, S. Jiao, Y. Jiang, H. Yan, D. Su, G. Sun, X. Yan and L. Sun

Genetic structure of 142 parent lines of sorghum [Sorghum bicolor (L.) Moench] was analyzed using model-based approach based on SSR markers. Forty-one selected from 103 SSR markers were used to analyze the parent lines, which generated 189 alleles revealed by each marker ranging from 2 to 11 with an average of 4.6 per marker. The polymorphic information content (PIC) value was 0.543 with a range of 0.089 to 0.850. All the parent lines were assigned to 7 subgroups, named Kafir, Kaoliang, Feterita, Shallu, Hegari, Milo and Durra. Parent lines without clear pedigree record were clustered into their corresponding groups, and genetic components of each line were estimated by Q-values. Information of this study would be useful for breeders to conclude their genetic background and select appropriate parents for germplasm improvement and hybrid breeding, and thus improve the efficiency of breeding programs.

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Authors: Wu Yanbo, Fu Jie, Zeng Sisi, Sun Peng and Yan Yingchun

Abstract

Thermal pyrolysis of pharmaceutical wastewater sludge, brown coal, and sludge-coal blends were studied by TG dynamic runs carried out at 20 °C min−1 in the temperature range from 25 to 850 °C. Different possible kinetic models of thermal decomposition have been considered. The best models of mechanism function for brown coal, pharmaceutical wastewater sludge, and coal–sludge blends are a first-order reaction, a N-dimensional nucleation, and growth reactions with N = 2 and 4, respectively. The Arrhenius kinetic parameters for brown coal, pharmaceutical wastewater sludge, and coal–sludge blends are proposed.

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Abstract  

The liquid-liquid extraction behavior of 2-ethylhexyltolylsulfoxide (EHTSO) towards uranium(VI) contained in nitric acid aqueous solution has been investigated. It was found that the extraction increases with increasing nitric acid concentration up to 5.0 mol/l and then decreases. Extraction also increases with increasing extractant concentration. The extracted species appears to be UO2(NO3)2 .2EHTSO. The influences of temperature, NH4NO3 and Na2C2O4 concentrations on the extraction equilibrium were also investigated and the thermodynamic functions of the extraction reaction were obtained.

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Authors: Hui Zhao, Huaxiao Yan, Congwang Zhang, Binbin Sun, Yan Zhang, Shuangshuang Dong, Yanhui Xue and Song Qin

Abstract

The pyrolytic characteristics and kinetics of wetland plant Phragmites australis was investigated using thermogravimetric method from 50 to 800 °C in an inert argon atmosphere at different heating rates of 5, 10, 25, 30, and 50 °C min−1. The kinetic parameters of activation energy and frequency factor were deduced by appropriate methods. The results showed that three stages appeared in the thermal degradation process. The most probable mechanism functions were described, and the average apparent activation energy was deduced as 291.8 kJ mol−1, and corresponding pre-exponential factors were determined as well. The results suggested that the most probable reaction mechanisms could be described by different models within different temperature ranges. It showed that the apparent activation energies and the corresponding pre-exponential factors could be obtained at different conversion rates. The results suggested that the experimental results and kinetic parameters provided useful information for the design of pyrolytic processing system using P. australis as feedstock.

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Abstract

Background and aims

The working memory (WM) ability of internet addicts and the topology underlying the WM processing in internet addiction (IA) are poorly understood. In this study, we employed a graph theoretical framework to characterize the topological properties of the IA brain network in the source cortical space during WM task.

Methods

A sample of 24 subjects with IA and 23 matched healthy controls (HCs) performed visual 2-back task. Exact Low Resolution Electromagnetic Tomography was adopted to project the pre-processed EEG signals into source space. Subsequently, Lagged phase synchronization was calculated between all pairs of Brodmann areas, the graph theoretical approaches were then employed to estimate the brain topological properties of all participants during the WM task.

Results

We found better WM behavioral performance in IA subjects compared with the HCs. Moreover, compared to the HC group, more integrated and hierarchical brain network was revealed in the IA subjects in alpha band. And altered regional centrality was mainly resided in frontal and limbic lobes. In addition, significant relationships between the IA severity and the significant altered graph indices were found.

Conclusions

In conclusion, these findings provide evidence to support the notion that altered topological configuration may underline changed WM function observed in IA.

Open access
Authors: Guo Jin-xin, Sun Xuan, Yin Zhi-lei, Li Xue-mei, Yu Hai-yun, Yang Yan-zhao and Sun Si-xiu

Abstract  

The mechanism of solvent extraction of gold(III) in hydrochloric acid media with quaternary ammonium salt octadecyl dimethyl benzyl ammonium chloride dissolved in chloroform was studied. The influences of temperature, NaCl and HCl concentraction on the extraction equilibrium were also investigated. The extraction reaction is exothermic ( H° = -28.53±0.15 kJ/mol) and log K ex = 5.47±0.04.

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Temperature uniformity and heating rate subjected to radio frequency (RF) heating have major impact on the quality of treated low moisture foods. The objective of this paper was to analyse the influence of electrode distance on the heating behaviour of RF on condition that the sample shape, size, and location between the electrodes were defined. Considering peanut butter (PB) and wheat flour (WF) as sample food, a 3D computer simulation model was developed using COMSOL, which was experimentally validated by a RF machine (27.12 MHz, 6 kW). Specifically, the electrode distances were selected as 84, 89, 93, 99 and 89, 93, 98, 103 (mm) for RF heating of PB and WF, respectively. Results showed that the simulated results and experimental data agreed well; the temperature-time histories of the RF heating of PB and WF were approximate straight lines; both the temperature uniformity index and the heating rate decreased with the increase of the electrode distance; the heating rate had a negative logarithmic linear relationship with the electrode distance, which was independent of the types, geometry shapes and sizes of low moisture foods.

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Authors: Yang Yan-Zhao, Yang Yong-Hui, Jiang Xu-Chuan, Sun Si-Xiu and Bao Bo-Rong

Abstract  

The effect of diluents on the extraction of uranium(VI) with petroleum sulfoxides (PSO) was studied. The decreasing order of extraction ability of PSO is as follows: benzene, toluene, cyclohexane, heptane, kerosene, carbon tetrachloride and chloroform. The effect of temperature on the extraction equilibrium was also investigated and enthalpy of the extraction was obtained. The relationship between the extraction equilibrium constantsK ex and the physical parameters of diluents can be derived.

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Authors: Yang Yan-Zhao, Sun Si-Xiu, Zhang Lei, Yang Yong-Hui and Bao Bo-Rong

Abstract  

The liquid-liquid extraction of uranium(VI) from aqueous nitric acid with bis(octylsulfinyl)methane (BOSM) has been studied over a wide range of conditions. The extracted species appear to be UO2(NO3)2·2BOSM. It was found that the extraction increased with increasing nitric acid concentration up to 8.5 mol/l and then descreased. Extraction also increased with increasing extractant concentration. The influence of temperature and salting-out agent concentration on the extraction equilibrium has also been investigated, and the enthalpy of the extraction reaction was estimated.

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