In situ anchor of magnetic Fe304 nanoparticles （NPs） onto the surface of natural maifanite was realized by chemical oxidation coprecipitation in hot alkaline solution. The Fe304/maifanite composites were characteriz...In situ anchor of magnetic Fe304 nanoparticles （NPs） onto the surface of natural maifanite was realized by chemical oxidation coprecipitation in hot alkaline solution. The Fe304/maifanite composites were characterized by XRD, FTIR, SEM, and TEM. These results indicated that polycrystalline Fe304 NPs with inverse spinel structure were formed and tightly dispersed on maifanite surface. Based on the measurement of surface Zeta potential of maifanite at different medium pHs, the possible combination mechanism between natural maifanite and Fe304 NPs was proposed. Then, the as- obtained composites were developed as highly efficient heterogeneous Fenton-like catalyst for the discoloration of an azo dye, Methyl Orange （MO）. The comparative tests on MO discoloration in different systems revealed that Fe304/maifanite composite exhibited much higher Fenton-like catalytic activity than Fe304 NPs and the heterogeneous Fenton- like reaction governed the discoloration of MO. Kinetic results clearly showed that MO discoloration process followed the second-order kinetic model. Fe304/maifanite compo- sites exhibited the typical ferromagnetic property detected by VSM and could be easily separated from solution by an external magnetic field.展开更多
In order to improve the concentration of selenium in the maifanite concentrate, the optimum experimental conditions were obtained by orthogonal experimentas follows: size of maifanite was 10 mesh, concentration of mai...In order to improve the concentration of selenium in the maifanite concentrate, the optimum experimental conditions were obtained by orthogonal experimentas follows: size of maifanite was 10 mesh, concentration of maifanite was 15 (expressed as the quality of maifanite divided by that of water), soaking time was 60 min at room temperature, heating temperature was 70oC, heating time was 20 min, pH value was 6. Under this condition, the concentrations of each element (ppm)determined by ICP-AES were: Fe 0.099, Cu 0.035, Mn 0.051, Zn 0.019, Se 0.028, Al 0.000.a ven in this document.展开更多
Aiming to solve the problem of corrosion and high cost of the conductive fillers, the powders with the properties of anti-oxidation, corrosion resistance and thermal stability should be developed. A new modification t...Aiming to solve the problem of corrosion and high cost of the conductive fillers, the powders with the properties of anti-oxidation, corrosion resistance and thermal stability should be developed. A new modification technology, rare earth gaseous penetration, was applied to enhance the conductivity of maifanite in this paper, and the mechanism for improving the conductivity of maifanite effectively was speculated in detail for the variations of the composition, structure and morphology between the original and Er-penetration maifanite powders. The results of the resistivity show that Er-penetration can really improve the conductivity of maifanite powders. When the penetration temperature is 500 ℃, the resistivity of maifanite surprisingly declines to 93.2 Ω·m. Moreover, XRD and XPS patterns display that the cations in maifanite are substituted by Er^(3+) successfully, resulting in the production of electrons in the system, which is the key reason to heighten the conductivity of maifanite. Most importantly, Erpenetration maifanite, whose price is really low, can replace the expensive conductive powders and be used in the electronic industry to decrease the cost of the electronic devices.展开更多
Maifanite is a nature medicinal stone used in many fields for long time. Theresearch on it showed that there are many trace elements in maifanite. In this paper, 36 traceelements in maifanite were determined by outer ...Maifanite is a nature medicinal stone used in many fields for long time. Theresearch on it showed that there are many trace elements in maifanite. In this paper, 36 traceelements in maifanite were determined by outer cover electrode atomic emission spectrometry, and thedetermination conditions were studied systematically. The results show that the concentrations ofelements, which are beneficial to human health, are higher, and the elements harmful to peoplehealth such as As, Cd, Hg, Cr, and Pb are tiny in maifanite. The precision and the accuracy werealso discussed.展开更多
基金This work was financially supported by the National Natural Science Foundation of China （Grant No. 51404083）, the Program for New Century Excellent Talents in Heilongjiang Provincial Universities （Grant No. 1253-NCET-010）, the Research Development Fund of Nianzishan Institute of Maifanite, Qiqihaer （Grant No. 201406）, and the Natural Science Foundation of Heilongjiang Province, China （Grant No. E2015065）.
文摘In situ anchor of magnetic Fe304 nanoparticles （NPs） onto the surface of natural maifanite was realized by chemical oxidation coprecipitation in hot alkaline solution. The Fe304/maifanite composites were characterized by XRD, FTIR, SEM, and TEM. These results indicated that polycrystalline Fe304 NPs with inverse spinel structure were formed and tightly dispersed on maifanite surface. Based on the measurement of surface Zeta potential of maifanite at different medium pHs, the possible combination mechanism between natural maifanite and Fe304 NPs was proposed. Then, the as- obtained composites were developed as highly efficient heterogeneous Fenton-like catalyst for the discoloration of an azo dye, Methyl Orange （MO）. The comparative tests on MO discoloration in different systems revealed that Fe304/maifanite composite exhibited much higher Fenton-like catalytic activity than Fe304 NPs and the heterogeneous Fenton- like reaction governed the discoloration of MO. Kinetic results clearly showed that MO discoloration process followed the second-order kinetic model. Fe304/maifanite compo- sites exhibited the typical ferromagnetic property detected by VSM and could be easily separated from solution by an external magnetic field.
文摘In order to improve the concentration of selenium in the maifanite concentrate, the optimum experimental conditions were obtained by orthogonal experimentas follows: size of maifanite was 10 mesh, concentration of maifanite was 15 (expressed as the quality of maifanite divided by that of water), soaking time was 60 min at room temperature, heating temperature was 70oC, heating time was 20 min, pH value was 6. Under this condition, the concentrations of each element (ppm)determined by ICP-AES were: Fe 0.099, Cu 0.035, Mn 0.051, Zn 0.019, Se 0.028, Al 0.000.a ven in this document.
基金Project supported by the Projects of Application Technology and Development of Harbin(2016RAXXJ024)
文摘Aiming to solve the problem of corrosion and high cost of the conductive fillers, the powders with the properties of anti-oxidation, corrosion resistance and thermal stability should be developed. A new modification technology, rare earth gaseous penetration, was applied to enhance the conductivity of maifanite in this paper, and the mechanism for improving the conductivity of maifanite effectively was speculated in detail for the variations of the composition, structure and morphology between the original and Er-penetration maifanite powders. The results of the resistivity show that Er-penetration can really improve the conductivity of maifanite powders. When the penetration temperature is 500 ℃, the resistivity of maifanite surprisingly declines to 93.2 Ω·m. Moreover, XRD and XPS patterns display that the cations in maifanite are substituted by Er^(3+) successfully, resulting in the production of electrons in the system, which is the key reason to heighten the conductivity of maifanite. Most importantly, Erpenetration maifanite, whose price is really low, can replace the expensive conductive powders and be used in the electronic industry to decrease the cost of the electronic devices.
文摘Maifanite is a nature medicinal stone used in many fields for long time. Theresearch on it showed that there are many trace elements in maifanite. In this paper, 36 traceelements in maifanite were determined by outer cover electrode atomic emission spectrometry, and thedetermination conditions were studied systematically. The results show that the concentrations ofelements, which are beneficial to human health, are higher, and the elements harmful to peoplehealth such as As, Cd, Hg, Cr, and Pb are tiny in maifanite. The precision and the accuracy werealso discussed.
