To solve the problem of excess molybdenum, a new composite nanomaterial was prepared for adsorption and removal of Mo (VI). Chitosan-modified magnetic nanoparticles (Fe3O4/CTS) were prepared by the method of glutaraldehyde crosslinking. The morphology of the composite nanoparticles was characterized by a scanning electron microscope, and the magnetic properties of the nanoparticles were characterized by an external magnetic field. The content of Mo (VI) was determined by thiocyanate spectrophotometry. The relationship between adsorbent dosage, oscillation velocity, contact time and removal of Mo (VI) was studied. The results showed that when the dosage of Fe3O4/CTS magnetic nanoparticles was 0.4 g, the oscillation speed was 100 r min-1, and the contact time was 10 min, 100 ml of Mo (VI) solution was treated under the condition of initial pH =4, and the removal effect of Fe3O4/CTS magnetic nanoparticles on Mo (VI) was the best. Treatment effluent can reach the comprehensive sewage discharge standard in Liaoning Province. At the same time, it is proved that Fe3O4/CTS magnetic nanoparticles are a kind of adsorbent which is easy to recover, easy to separate magnetically, and has the ability to remove Mo (VI) efficiently.

This paper studied 30 cold-formed steel columns with three different sections and eleven different eccentricities under eccentric compression loading by nonlinear finite element analysis using program ANSYS. Effects of the above parameters on ultimate load-carrying capacity, buckling modes, the distribution of stress and strain, and deflection behavior of channels with complex edge stiffeners under eccentric compression loading were investigated. The result shows that influence of the effective centroid offset on carrying capacity under eccentric compression loading can not be ignored. The maximum of ultimate load-carrying capacity appeared when effective eccentricity was 0mm, and decreased with the increase of the value of effective eccentricity. Sections influence on load-carrying capacity under negative eccentric compression loading. Web stiffening can improve load-carrying capacity which the eccentricity near the web side. Sections influence on buckling modes. web stiffening can effectively avoid local buckling.

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Zn 3 P 2 is an acute and effective rodenticide used widely to protect grains in stores and domestically to kill rodents. This study aims to postpone the time of poisoning symptoms after eating Zn 3 P 2 and improve the effect of killing rodents. Zn 3 P 2/calcium alginate ( Zn 3 P 2/ CA ) was synthesized through the reaction of sodium alginate and calcium chloride by the reversed-phase microemulsion method and then loaded with Zn 3 P 2 technical. It was characterized by X-ray diffractometer, laser particle size analyzer, scanning electron microscope (SEM) and transmission electron microscopy (TEM). The drug loading capacity, slow-controlled release performances and toxic effects were also investigated. The results showed that Zn 3 P 2/ CA was spherical, average particle size was 353.9 nm, and particle dispersion index (PDI) was 0.195. The mass ratios of calcium alginate and Zn 3 P 2 technical ( CA / Zn 3 P 2) had significant impacts to drug loading capacity and slow-controlled release performances of Zn 3 P 2/ CA . The palatability and efficacy of Zn 3 P 2/ CA were significantly improved and enhanced compared with Zn 3 P 2 technical. The results showed that Zn 3 P 2/ CA presented high loading efficiency, commendable sustained-release performance and good environmental compatibility, and this delivery carrier may be extended to other slow-controlled release and high-efficient pesticide formulation in future.

This paper presents finite element analysis on cold-formed steel-section columns with complex edge stiffeners and web holes under axial compression. A total of 18 channel models with different parameters such as length, thickness and flange width are simulated. Failure modes, the ultimate load and the stress distribution around web holes are researched. The analysis results show that, the main failure mode of-section columns with complex edge stiffeners and web holes is distortional buckling. The carrying efficiency is higher as the thickness-width ratio increasing. Because of perforations on the web, the position of the max stress changes from the web near the mid-height of the specimens to the location adjacent to holes.