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- Author or Editor: Y. Fang x
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Abstract
In order to enhance the electrogenerative leaching rate of sphalerite reasonably, the basic principle of generative process was applied to the simultaneous leaching of sphalerite in the presence of MnO2. It was confirmed by experimental results that both mental ions and electric energy could be obtained in the simultaneous electrogenerative leaching process. The leaching cell had the open circuit potential about 1.0 V, about 2000 C of electric quantity was obtained, the optimal leaching ratio of Zn2+ and Mn2+ was 48.5, 39.6% respectively, after electrogenerative leaching for 11 h.
Abstract
Samples of archaic bronze have been investigated by fast neutron activation analysis using both the absolute and relative method. The components Cu, Zn, Sn and Pb have been determined quantitatively. For the detection of lead via the short-lived isomeric state207mPb, cyclic activation and measurement technique was used with pneumatic sample transfer between detector and central irradiation position of the neutron tube. For nondestructive analysis of antique Chinese coins the samples had to be irradiated outside the neutron generator KORONA. The activation reactions, the evaluation of the elemental concentrations and the accuracy of the results are discussed. The data were corrected for 
-ray self-absorption in the samples and summing of coincident -rays in the detector. According to reported typical compositions of Chinese bronze from different dynasties, the age of the samples has been derived from the results obtained.
Abstract
The electrogenerative-leaching of galena activated mechanically in planetary centrifugal mill were studied. A dual cell system was introduced to investigate the leaching process. The experimental results indicated that the mechanical activation improved the galena’s lattice constant, the lattice distortion and the degree of crystal defect, which resulted a decreasing of initial potential of galena electrode and an increasing of output voltage of the leaching cell.
Abstract
Electrochemical reduction of U(VI) in nitric acid-hydrazine solution is greatly influenced by the concentration of nitric acid. In low acidity nitric acid solution such as 0.1M (M=mol/dm3) HNO3, U(VI) was firstly reduced to U(V) and then partially reduced to U(IV). In high acidity nitric acid solution, e.g., 3-6M HNO3, an electrode process of two-electron transfer was involved in the reduction of U(VI). A higher U(IV) yield could be achieved in nitric acid solution with higher concentration. Hydrazine was very effective in suppressing the reduction of concentrated nitric acid, and the optimal concentration of hydrazine added was 0.075 to 0.15M in 6M HNO3
Abstract
The principle for the electro-generative simultaneous leaching (EGSL) is applied to simultaneous leaching of pyrite-MnO2 in this paper. A galvanic system for the bio-electro-generative simultaneous leaching (BEGSL) has been set up. The equation of electric quantity vs. time is used to study the effect of produced sulfur on electro-generative efficiency and quantity. It has been shown that the resistance decreased in the presence of Acidithiobacillus thiooxidans (A. thiooxidans) with the increase of electro-generative efficiency. The effects of temperature and grain size on rate of ferrous extraction from pyrite under the conditions of presence and absence of A. thiooxidans were studied, respectively. The changes in the extraction rate of Fe2+ as particle size in presence of A. thiooxidans were more evident than that in the absence, which indicated that the extraction in bio-electro-generative leaching was affected by particle size remarkably. Around the optimum culture temperature for A. thiooxidans, the bigger change in the conversion rate of Fe2+ was depending on temperature. The transferred charge in BEGSL including part of S0 to sulfate group in the presence of (A. thiooxidans) which is called as biologic electric quantity, and the ratio of biologic electric quantity reached to 58.10% in 72 h among the all-transferred charge.
Abstract
Research on extracted 90Y with di(2-ethylhexyl) orthophosphoric acid (P204) in lipiodol for liver cancer was made to evaluate the stability of extracted 90Y with P204 in lipiodol (90Y-P204-lipiodol) in serum of newly-born cattle and human’s blood. At first, P204 (extractant) was dissolved in lipiodol (organic phase). Secondly, 90Y was extracted to organic phase after adding 90Y solution into test tube with P204 and lipiodol in it. The extracting efficiency with 0.01 mol/l P204 could reach 99.4%. The stability of 90Y-P204-lipiodol has been experimented in physiological saline solution as preparation for further stability experiment. The result indicated that the extracted 90Y lost 0.02%–0.36% in physiological saline solution. The results of further stability experiment showed that loss efficiencies of extracted 90Y after adding newly-born cattle serum 1 hour, 1 day, 3 and 7 days are 3.38%, 3.12%, 4.29% and 6.62%, respectively, and loss efficiencies of extracted 90Y after adding human’s blood 1 hour, 1 day, 3 and 7 days are 2.55%, 5.91%, 7.88% and 5.63%, respectively. Our data also indicated that 90Y is the most possible radioisotope for being extracted with P204 in lipiodol to treat hepatocellular carcinoma, particularly in cases of unresectable liver tumors, since 90Y is available from several commercial sources in clinical quality. We conclude that the stability of 90Y-P204-lipiodol tested with newly-born cattle serum and human’s blood attained great results. 90Y-P204-lipiodol is a kind of potential and exciting pharmaceutical in inerventional therapy for liver cancer and we can carry on the further animal test and clinical trial.
Summary
To control the quality of Euonymus fortunei (Turcz.) Hand.-Mazz., a simple and reliable method of high-performance liquid chromatography (HPLC) coupled with photodiode array detector (PAD) was developed for both fingerprint analysis and quantitative determination. Four representative flavonoids, namely, kaempferol-3-O-β-D-glucopyranosyl-(1→4)-α-L-rhamnopyranosyl-7-O-β-D-glucopyranosyl-(1→4)-α-L-rhamnopyranoside (I), kaempferol-3,7-O-α-dirhamnopyranoside (II), apigenin-7-O-β-D-glucopyranoside (III), and kaempferol-3-(4″-O-acetyl)-O-α-L-rhamnopyranoside-7-O-α-L-r hamnopyranoside (IV) isolated from E. fortunei, were used as reference compounds and simultaneously determined by the validated HPLC method. The unique properties of the chromatographic fingerprint were validated by analyzing 11 batches of E. fortunei, E. japonicus, E. laxiflorus, E. myrianthus, and E. hamiltonianus samples. Our results revealed that the chromatographic fingerprint combined with similarity measurement could efficiently identify and distinguish E. fortunei from the other investigated Euonymus species.
Abstract
A dual cell system was used to study the electrogenerative leaching sphalerite-MnO2 under the conditions of presence and absence of Acidithiobacillus ferrooxidans (A. ferrooxidans). The polarization of anode and cathode, and the relationship between the electric quantity (Q) and some factors, such as the dissolved Zn2+, Fe2+, the time in the bio-electro-generating simultaneous leaching (BEGSL) and electro-generating simultaneous leaching (EGSL), were studied. The results show that the dissolved Zn2+ in the presence of A. ferrooxidans is nearly 60% higher than that in the absence of A. ferrooxidans; the electrogenerative quantity in the former is about 134% more than that in the latter. A three-electrode system was applied to study anodic and cathodic self-corrosion current, which was inappreciable compared with the galvanic current between sphalerite and MnO2. The accumulated sulfur on the surface of sulfides produced in the electrogenerative leaching process could be oxidized in the presence of A. ferrooxidans, and the ratio of biological electric quantity reached to 31.72% in 72 h.
Abstract
The paper presents the results of determination of extractable organohalogens (EOX) by instrumental neutron activation analysis (INAA), and polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) by gas chromatography (GC), in atmospheric precipitation in Shanghai, China, from January to August 2005. The results showed that EOCI was the major component of organohalogens in precipitation. A significant correlation between the concentrations of EOBr and EOI was observed (r 2 = 0.75), which suggested that EOBr and EOI in precipitation might mainly come from the same sources. There were no clear seasonal trends for the concentrations of EOX. The concentrations of ΣPCBs ranged from 0.2–2.8 ng/l, with the dominant PCBs containing 3 to 5 chlorine atoms. HCH was the predominant pesticide in precipitation, accounting for over 80% of total OCPs, in which β-HCH took 28%–72% of total HCH. Also, there may be an evidence for significantly historical usage of DDT.
