Determination of trace elements in maifanite by outer cover electrode atomic emission spectrometry

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.

Applied Orthogonal Experiment Design for the Optimum Extraction Conditions of High Concentration Selenium from Maifanite

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.

Protective effect of maifanite against cadmium-induced oxidative stress to rats hippocampus by regulating the balance and metabolism of metals

In this paper, the author reported the effect of maifanite on the learning and memory of rats suffering Cd poisoning by step-down and step-through test, analyzed the content of MDA, MT, SOD, and GSH-Px in the hippocampus of rats respectively, and assayed the content of Fe, Cu, Zn, Mn, Se, and Cd in the hippocampus of rats. In the step-down test, it is found that maifanite can reduce the number of electric shock, prolong step-down latency, and cut down error times when rats are exposed to Cd 24 h. In the step-through test, maifanite can obviously prolong the latency of entering the dark cabin of rats suffering Cd poisoning. The exogenous Cd can lead to the decrease of SOD and GSH-Px activity and the increase of MDA and MT content. The alternation of maifanite and Cd by the gavage can significantly increase the SOD and GSH-Px activity as well as MT content, while lessening the MDA content. The accumulation of exogenous Cd in hippocampus causes the increase of Zn, Fe, Mn, and Cd content, and the decrease of Cu and Se content. The intake of maifanite can regulate the imbalance of metals content and make its content near to the of level control group. The research shows that maifanite can improve the ability of learning and memory of rats suffering Cd poisoning, increase MT formation and lower hyperoxidative damage. Maifanite has the function of balancing the content of trace elements in rats suffering Cd poisoning, and meanwhile can alleviate the toxicity of Cd effectively.

In situ anchor of magnetic Fe304 nanoparticles onto natural maifanite as efficient heterogeneous Fenton-like catalyst

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.

A novel inexpensive conductive material:Er-modified maifanite by gaseous penetration technology

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.