Advanced Materials Research Vols. 926-930

Abstract: Based on the analysis of the properties of spent catalyst, extract vanadium and molybdenum from spent catalyst by roasting alkaline leaching. Sodium carbonate was leaching agent. The effects of roasting temperature, roasting time, the concentration of sodium carbonate and the number of leaching times on the leaching rate of vanadium and molybdenum were studied. Roasting temperature of 650°C, roasting time of 3h, the concentration of sodium carbonate of 50g/L and once counter-current leaching, under this condition, the leaching of vanadium is 83% and the leaching of molybdenum is 93%.Roasting alkaline leaching has good effect on extracting vanadium and molybdenum from spent catalyst.

Abstract: In bimetallic clusters, the component and position of doping atoms can influence on structures and properties. It may induce irregular physical and chemical properties by tuning the doping atoms. In this study, (PdAg)₃₀₉ clusters with different contents and positions of doping Ag atoms have been investigated by molecular dynamics simulation based on the embedded atom method. It is found that the structure of (PdAg)₃₀₉ clusters transformed from truncated octahedron to icosahedron, and melting in heating processes from 200 K to 1500 K. Results indicated that the temperature of structural transformation and melting are strongly related to the number and position of doping Ag atoms. The melting point decreased with the increased Ag atoms, but there is irregular by doping Ag atoms at different position. The structural transformed temperature from truncated octahedron to icosahedron decreased with the increasing Ag atoms and the outer doping position. This means that the effect of doping Ag atoms can be used to tune the special structures of bimetallic clusters.

Abstract: Co₆₄Fe₄Si_14.5B_14.5 amorphous ribbon was fabricated by the melt-spinning technique. Soft magnetic properties of the ribbon were improved by annealing at 623K for 1 hour with a zero magnetic field, a 50mT longitudinal or transverse external magnetic field comparing with the as-quenched ribbon. The longitudinally driven giant magneto-impedance (LDGMI) effect and its field sensitivity (ξ) have been investigated in the frequency (f) range of 1kHz~1MHz. It is found that at f=51kHz, the LDGMI effect and ξ reach the largest values for the sample annealed with a longitudinal magnetic field.

Abstract: In this paper, low temperature oxygen plasma treatment method was adopted to process the carbon fiber surface. Flexural Strength test method was utilized to represent f composite material flexural strength. This paper observed flexural failure morphology of composite material by aid of SEM, then it compared the mechanical property, hygroscopicitiy and flexural strength retention rate of composite material before and after the plasma treatment. Results showed that the optimum treatment conditions of carbon fiber were 300W treatment power and 15-minute treatment time. Under the condition, the highest flexural strength value be increased by 19.55%.Saturated bibulous is low and bibulous rate is slow, flexural strength retention rate is 94.9%. And at the same time PES-C resin matrix can be strengthened, which will further improve the mechanical properties of composite materials.

Abstract: The magnetic composite microspheres of cassava starch have been prepared by magnetization of one-step oxidation, using cassava starch as natural macromolecule material. The condition effect on magnetic content was evaluated by single factor experiments, such as the mass concentration of starch, reaction temperature, reaction time, stirring speed, initial pH and ferrous solution volume. Preparation conditions were optimized by these evaluation experiments. The prepared magnetic composite microspheres were characterized by infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscope (SEM), and other means.

Abstract: GSY high-water swelling diagenetic powder has properties of good suspension, high flowability, easy to pump, and adjustable initial setting time. It has advantages of high expansion rate and easy for plug drilling comparing to Class G oil well cement through property test. Principles of selecting well for GSY high-water swelling diagenetic powder plugging technology are analyzed in this paper, and aiming at the disadvantages of sealing leakage section above cement top such as the slurry retention quantity is too little to form effective clay plug, and the first time sealing success rate is relatively low, research and application for the multi-slug plugging technology and pre diaphragm, post sealing plugging technology is developed, and good plugging effect is achieved in oilfield.

Abstract: We have established the isentropic compression curve T(P) and educed the W-J parameter of Graphite. A series of rapid compression processes were conducted with Graphite up to 4.58GPa. Pressure jumps and induced temperature increasing were recorded. The temperature change was corrected to exhibit an adiabatic condition. The T(P) curve was fitted with maximum levels of the pressure and temperature, and the W-J parameters was determined by investigating its dependence on temperature and pressure. The results showed that the experimentally measured W-J parameters are increased with increasing pressure.

Abstract: Membrane bioreactor (MBR) has developed rapidly in recent years; however, the membrane fouling problems are affecting its further widespread application. This paper discusses the role of metal ions in the mixture in the mechanism; also on the high-priced metal ions coexist in the mixture when the effects of biological flocculation process; finally, the direction of future research in this area are summarized.

Abstract: We developed a plane-strain crystal plasticity finite element (CPFE) numerical model to predict the tensile behavior of twinning-induced plasticity (TWIP) steel with both slip and mechanical twinning as the main deformation modes. Our CPFE model may not only predict well the tensile stress versus strain (S-S) curve but also capture the variation in the volume fraction of twins with a reasonable accuracy. The nucleation of mechanical twin is obviously controlled by the stress concentration. At the same time, the growth of twin may either lead to a stress relaxation in the matrix or cause a local stress concentration around twin, which depends on the deformation condition.

Abstract: Herein a new crystalline zirconium oxide was prepared by the sol-gel precipitation and calcination methods. TEM analysis proved that the prepared ZrO2 particles are nanosized particles with average size of 10-20nm and XRD further illustrated its crystal pattern in nature. The competition tests also demonstrated its excellent selectivity towards lead ions by comparing D001 resin. Moreover, the resultant ZrO2 particles could be regenerated and reused at least 3 cycles.