Papers by Keyword: Iron

Abstract: The objective of this research was to develop a new form of clad layer by producing a Silicon Carbide (SiC) particle reinforce Metal Matrix Composite (MMC) using the iron based alloys as the matrix material. A 1.2kW continuous wave CO₂ laser was used in this research. A gravity feed system was used with one powder feed which contained different percentages of SiC particles and iron based powder. Experimental results showed that the decomposition of SiC particles was observed and only a few SiC particles were found in the clad matrix. High micro hardness values were found in the SiC clad which were in excess of 1000 HV. However, most of the SiC were evaporated which created porosity in the melt pool. Therefore, blown powder technique is recommended for overcome this problem.

Abstract: Through designing orthogonal tests, the influence mechanism of iron to the growth of fresh water algae was studied. The results indicated that the initial Fe concentration of 0.3mg/L or above can lead to high algae relative growth rate while the initial Fe concentration under 0.3mg/L can only generate low algae relative growth rate. The consumption of iron in Group LNLP under low initial Fe concentration and Group HNHP under high initial Fe concentration was in synchronism with the consumption of nitrogen and phosphorus. However, in Group HNHP under low initial Fe concentration and Group LNLP under high initial Fe concentration the concentration of iron decreased with the increase of algal biomass before reaching the peak value of algal biomass and it increased after reaching the peak value in contrary. Among all those 25 groups the order of the peak value of algal biomass from big to small is as follows:All-rich Group>Nitrogen-lacked Group>Phosphorus-lacked Group>Iron-lacked Group>All-lacked Group. The lack of Fe content will restrain the growth of algae. In certain concentration rage algal biomass increased with the increasing of Fe content while Fe content will restrain the growth of algae in contrary if beyond the concentration rage.

Abstract: According to the present situation of lack of systemic analysis for manufacturing resources optimization operation for iron and steel enterprise in domestic and overseas, a resource input/output frame about steel and iron manufacturing unit was established to analyze the resource consumption situation, and the main line of steel green manufacturing resources was built, which is based on the theory and method of green manufacturing and the operation law of iron and steel enterprise. And manufacturing resources optimization operation strategies were put forward for iron and steel enterprises, considering the resource transformation and consumption from the whole steel product life cycle. The operation strategies can provide guidance ideas for the iron and steel enterprises the most efficient use of material resources and the least energy consumption in the steel manufacturing process.

Abstract: A layered structure of different iron oxides was produced by thermal oxidation of iron. The structure and microstructure of different layers were examined using scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Selected area electron diffraction (SAED) was used to identify the structures of the different oxide layers. Two different structures of Fe₂O₃ were found to co-exist. Based on our observation, a possible oxidation mechanism for iron was proposed. The results shed light on the oxidation process of metals and provide insight into the synthesis of iron oxides.

Abstract: An ultraviolet (UV) shielding agent based on Fe-doped zinc oxide nanorods (ZnONRs) was synthesized by ex-situdoping using spray pyrolysis technique. These Fe-doped ZnO NRs could reduce the inherent photocatalytic activity of zinc oxide while still maintaining their ultraviolet filtering capability. In this work, the effect of doping duration by spray pyrolysis technique on the optical property and photocatalytic efficiency of ZnO NRs was studied. The room temperature photoluminescence (PL) analysis on the Fe-doped ZnO NRs indicates the red-shift of violet emission peak, i.e. from 378.97 nm (undoped) to 381.86 nm (60 mins.doping). Besides, the reduction of I_UV/_Vis ratio of PL reveals that the ex-situ Fe doping deteriorated the crystal quality of ZnO NRs. The photocatalytic study shows that the rate constant of Fe-doped ZnO NRs was smaller than the undoped ZnO NRs. It means that the Fe-doped ZnO NRs were less effective in degrading the RhB solution.

Abstract: This study presents the development of an in-situ analyzer, ‘IonConExplorer’, which can detect iron concentration in deep seawater at maximum 4000 meters with the method of spectrophotometry coupling with liquid waveguide capillary cell. The detection of limit is 27.25nM (n=20) for Fe(II) at 562nm, while the linear range is 100 nM - 1 μM. On the whole linear range, relative standard deviation of the seven replicate measurements is less than 2%. IonConExplorer is composed of pressure house and equipressure house containing control unit and fluid system, respectively. Via TCP protocol of network communication protocol(TCP/IP) when connecting to the ocean observing network, IonConExplorer transfers abundant real time data instantly to the shore-based station, demonstrating high temporal and spatial distribution resolution of iron.

Abstract: Iron has been viewed as a promised biodegradable metal for temporary implants but its slow degradation is considered as the main limitation. Some works have been done to improve its degradation rate including by alloying and by processing through powder metallurgy. This work presents new approach to accelerate the degradation rate of iron by infiltrating biodegradable polymer into the pores of bulk iron foam. Solution of poly(L-lactic-co-glycolic acid) or PLGA was infiltrated into the iron foam by vacuum infiltration method to form PLGA-infiltrated porous iron (PIPI). It was found that the existence of PLGA in the iron foam maintained the mechanical property as that of iron foam. Degradation test has shown that the PLGA lead the degradation in PIPI samples. This preliminary work has shown the potentiality of the incorporation of biodegradable polymers into biodegradable metals for tailoring their degradation rate.

Abstract: Zero-valent iron nanoparticles( nano-Fe0) were applied as a treatment tactics for a uranium-containing mine wastewater taken from Shaoguan, Guangdong, China. Different factors including pH value, nano-Fe0 dosage,reaction time were introduced to study the effect posed by those factors.Results indicated that those factors have significant effect on uranium removal rate.The best removal effect happened when pH=5~6, nano-Fe0 iron dosage is 2g/l,reaction time is 1h.It is also demonstrated that nano-Fe0may be an effective material for treatment of complex uranium-contaminated effluent.

Abstract: AC magnetic heating of superparamagnetic Co and Fe nanoparticles for application in hyperthermia was measured to find a size of nanoparticles that would result in an optimal heating for given amplitude and frequency of ac externally applied magnetic field. To measure it, a custom-made power supply connected to a 20-turn insulated copper coil in the shape of a spiral solenoid cooled with water was used. A fiber-optic temperature sensor has been used to measure the temperature with an accuracy of 0.0001 K. The magnetic field with magnitude of 20.6 μT and a frequency of oscillation equal to 348 kHz was generated inside the coil to heat magnetic nanoparticles. The maximum specific power loss or the highest heating rate for Co magnetic nanoparticles was achieved for nanoparticles of 8.2 nm in diameter. The maximum heating rate for coated Fe was found for nanoparticles with diameter of 18.61 nm.

Abstract: In this paper, the soil simulation pot experiment was carried out to study the impacts of trace elements iron (Fe) and zinc (Zn) on availability of cadmium (Cd) and lead (Pb). The self-made Cd and Pb compound contaminated soil was taken as the test soil, and wheat was taken as the test plant. The results show that with the increase in Fe dosage, overground dry weight, root dry weight, and total dry weight of wheat gradually increase; the application of Zn reduces overground dry weight, root dry weight, and total dry weight of wheat. Meanwhile, wheat biomass under Cd and Pb combined pollution is smaller than that under single Cd pollution or single Pb pollution. The application of Fe fertilizer increases Cd absorption of various parts of wheat. In the single Cd pollution treatment, with the increase in Fe dosage, Cd concentrations in roots, stems and leaves of wheat will first be increased, then decreased; in Cd and Pb combined pollution treatment, with the increase in Fe, Cd concentrations in roots, stems and leaves of wheat will also be increased. The application of Fe promotes the Pb absorption of wheat. With the increase in Fe dosage, Pb concentrations in roots, stems and leaves of wheat will first be increased, then decreased slightly. Compared with Zn0, Cd concentrations of different parts of wheat after Zn1 and Zn2 treatment increase significantly. In addition, with the increase in Zn dosage, Cd concentrations of different parts of wheat will first increase, then decrease. Regardless of single Pb pollution treatment or Cd and Pb combined pollution treatment, Pb concentrations of different parts of wheat decrease as Zn dosage increases. Under different Fe and Zn levels, and when Cd and Pb coexist, Pb can promote Cd absorption of plant, but Cd inhibits Pb absorption of plant.