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Magnesium alloy as a green material in the 21st century, because of its excellent physical and mechanical properties of metallic materials as an ideal in the automotive industry, electronic industry and aviation, aerospace and other industries[1]. However, poor corrosion resistance of magnesium alloys become an important issue hinder application of magnesium alloys[2]. So magnesium alloy corrosion problems and the current status of research paper reviews several magnesium alloy protection methods at home and abroad, and also highlighted with our latest laser shock (LSP) study of AZ91 magnesium alloy at high strain rates of corrosion resistance results.

Dust particles and organic contaminants in environment can intrude into electronic device interior through the shell and opening holes. The intrusive contaminants can adhere on electric contact interface. Therefore, it can reduce components’ electric connection reliability. Widely it used acoustic dust-proof mesh to protect the mobile phone and other electric devices’ earpieces and speakers from contamination intrusion. This preventing contamination role makes much dust particles and organics adhere on the mesh. It is necessary to evaluate dust-proof mesh ability against contamination. In this paper, actual field contaminated meshes have been taken failure analysis. Then, lab simulation experiments have been established with considering meshes and contaminants’ characters. Finally the influence of mesh’s parameter on contamination has been researched.

The effect of surfactant on improving the leaching rate of uranium was studied under both batch and column experiments. Batch experiments show that surfactant DMSS can improve the leaching rate and the the surface tension is decreased about 55.29%. 70 mg/l DMSS has the highest leaching rate of uranium , which close to the micellar concentration of DMSS. In the column study, with the addition of DMSS, the leaching rate of uranium is improved 8.3%. Thus the surfactant DMSS can accelerate leaching of uranium.

This study investigates the degradation of Nonylphenol. The degradation affecting factors including solution ozone dosage, initial concentration, pH, temperature and ultraviolet. The results indicated that when the ozone contents changes, the Nonylphenols degradation rate changes as well. The higher ozone concentration contribute to the faster degradation; With the increase of initial concentration of Nonylphenol, the removal rate of it decrease on the contrary, while with the initial concentration increases, the quality of unit ozone degradation of Nonylphenol is ascenting and then tend to a constant; The remove rate of Nonylphenol is improving when the pH value vary from 4.86~10.34. The effect of Nonylphenols ozonation in higher temperatures is better than it is in lower temperature; Ultraviolet radiation is also favorable for the removal of Nonylphenol as it can shorten the reaction time as well as reduce the amount of ozone.

This study investigates the degradation of bisphenol A (BPA). The degradation affecting factors including solution ozone dosage, initial concentration, pH, temperature and ultraviolet. The results indicated that when the ozone contents changes, the BPAs degradation rate changes as well. The higher ozone concentration contribute to the faster degradation; With the increase of initial concentration of BPA, the removal rate of it decrease on the contrary, while with the initial concentration increases, the quality of unit ozone degradation of BPA is ascenting and then tend to a constant; The remove rate of BPA is improving when the pH value vary from 4.86~10.34. The effect of BPAs ozonation in higher temperatures is better than it is in lower temperature; Ultraviolet radiation is also favorable for the removal of BPA as it can shorten the reaction time as well as reduce the amount of ozone.

In the current study, on the behavior of dust particle, JIS-11 test particles were used as simulated particles. However, existing particles in the background might have influenced the measurement results of JIS-11 test particles. This study measured and selected particulate matter as dust particle in indoor environment using an experimental box. The concentration of riboflavin shows less effect from the background, therefore, riboflavin particles were used as the dust particulate matter.

Dust particle which includes corpses and feces of the mite, animal dander, cockroaches, and mould spores can reach the lung of human and then trigger asthma disease easily. In this research, experimental studies were carried out in order to examine particle removal efficiency in a room with two ventilation systems: a ceiling exhaust system and a slit exhaust system. The results indicated that there was no clear relationship between removal efficiency and two different outlet locations. Also, from the results after the decay, the particle count in the case of the ceiling exhaust was higher than that in the case of the slit exhaust.

The mineral processing flow sheet and reagent system of flotation copper minerals from a large copper-iron deposit in Yunnan were fully investigated. The results indicate that the optimum conditions for flotation of copper minerals from the material were identified as grinding fineness of 85%, dosage of CaO at 2000g/t , dosage of Na2S at 200 g/t, dosage of butyl xanthate 40g/t. Under such a condition, a copper recovery of 88.17% with a concentrate grade of 26.86% was achieved from the material using a closed circuit flow sheet of "one-stage roughing flotation, one-stage cleaning flotation and one-stage scavenging flotation.

The study attempts to produce iron concentrate from a high-purity pyrite concentrate using oxidizing roasting at industry scale. The effect of key parameters, i.e., roasting temperature, excess air coefficient and roasting intensity on the Fe and S content in the pyrite cinder was fully investigated. The results indicate that the roasting temperature plays a key role in decrease the S content in the pyrite cinder; an increase in the roasting temperature from 800°C to 950°C decreased the S content in the pyrite cinder remarkably from 0.43% to 0.18%. The optimum conditions for produce a high quality iron concentrate from the high-purity pyrite concentrate were identified as roasting temperature around 900 ~ 950°C, excess air coefficient at 1.20 and roasting intensity at 4.36 ~ 5.61 t / m2•day. Under such a condition, high-quality iron concentrate containing 65.11% Fe and 0.21% S was achieved from the pyrite concentrate.

Greenway construction theory originates in western countries. At first, more emphasis was attached on the landscape function, which is the combination of artificial landscape and natural landscape. As the theory and practice develop, the green way construction is on its way to sophistication and maturity. Nowadays, it has become an essential way to improve the urban ecological environment and the urban life quality. This essay mainly reviews the origin of the greenway construction in foreign countries, the definition, phase classification, planning issues and functions etc and takes the experience of western countries as reference, hoping to shed some light on the theoretical innovation and practice of greenway construction in China.

The effect of CaO-B2O3-SiO2 glass on the densification, microstructure and microwave dielectric properties of Ba4Nd9.33Ti18O54 ceramics was investigated in this work. It was found that the addition of a few amount of glass (≤2%) could effectively decrease the sintering temperature owing to the viscous sintering. However, locally porous structures were formed when overmuch glass was added because of enwrapped air bubbles and rapid grain growth. In addition, the amount of remaining glass after sintering could be decreased due to the re-crystallization of CaO-B2O3-SiO2 glass. Sol-gel derived Ba4Nd9.33Ti18O54 ceramics containing 2 wt% glass can be well densified at 950°C and exhibit good microwave dielectric properties of εr=68 and Q×f=7400 GHz.

Six specimens of abnormal interior joints were tested under reversed cyclic loading. Experimental studies were carried out to investigate the influence of joint core dimensions and axial compression ratio on crack resistance of abnormal joints. The results showed that the crack resistance capacity was mainly provided by the minor core concrete (determined by the top column and the small beam) , and the minor core concrete was in elastic stage before cracks appeared. Furthermore, axial compression ratio was a significant parameter to increase the crack resistance capacity. Based on the test results, a theoretical formula of crack resistance capacity was proposed. The calculated crack resistance capacities of 11 abnormal interior joints were compared with the experimental results, and a good agreement was obtained.

Iron ore tailings and waste rock are solid waste during mining in the steel industry. This paper presents the study on sintered wall materials made use of iron tailings and waste rock. The process parameters through chemical analysis and thermal analysis to determine the feasibility of using iron ore tailings and rock on sintered wall material. Plasticity index, firing shrinkage, water absorption, apparent porosity and bulk density are tested, and the proportion of these two materials are also determined. The results show that iron tailings and waste rock can be used to sinter MU15 wall materials, with the sintering temperature ranges 850-950°C, but shrinkage of the specimen (diameter and height shrinkage) of 2.5%-5.0%, and the apparent porosity 42% or more. This technology not only use both waste as raw material, furthermore, because of the higher iron content in iron ore tailings and waste rock, the products reduce the sintering temperature, decreased energy consumption. The technology uses waste as raw material, furthermore, due to the high iron content in the ore tailings and waste rock, the sintering temperature is decreased, which saves energy.

Compressive strength, setting time, hydration heat and hydration product were investigated to evaluate the effects of Zn2+ ion concentrations and the anion of zinc salts on the hydration characteristics of Portland cement paste. The results show that the hydration characteristics of zinc-doped cement pastes depend on Zn2+ ion concentrations and the anion of salts. With the incorporation of ZnCl2, the hydration heat, exothermic rate and the early-age strength of cement pastes were reduced, the arrival time of the highest temperature was delayed, and little negative influences on the compressive strength at 28 days were observed. The total hydration did not decrease incorporating ZnSO4; the hydration exothermic process was delayed. There were little negative influences on the compressive strength of the samples at 3 days and 28 days. Moreover, for the samples with the same Zn concentration, the retardation effect of ZnCl2 samples was stronger than that of ZnSO4 samples.

The electric contact is one of the most primary elements to affect the reliability of the electric systems. Gold finish can maintain high contact reliability but increase the manufacture cost. In this paper, the effects of one sided gold plated contacts with various thickness of gold finish on the contact reliability were investigated. The failure mechanism of the one sided gold plated contacts under fretting conditions was analyzed. The contact life and the optimum thickness of the one sided gold finish under fretting conditions was achieved and compared. The effect of the curvature of the probes on the contact life was also discussed.

The mesoporous molecular sieve MCM-41 was synthesized by hydrothermal synthesis method with iron ore tailings as starting material, and CTAB as appendage. The properties, kinetics and thermodynamics of Ni2+ from water adsorption process on MCM-41 residue were studied. The data demonstrated that the products possess typical properties of molecular sieve MCM-41, with specific surface area of 576 m2/ g, and the average pore size is 5.53 nm; the adsorption of MCM-41 residue to Ni2+ was decalescence reaction and the relationship between adsorbing capacity and equilibrium mass concentration is in accordance with the isothermal adsorption equations of Langmuir, and the removal rate of Ni2+ increases with the increasing of pH.