Advanced Materials Research Vols. 396-398

Abstract: Salicylaldehyde azine (SA) were synthesized with salicylaldehyde and hydrazine hydrate as a raw material. The crystal structure was characterized by X-ray diffraction, as well as the total antioxidant capacity and antibacterial activities against Staphylococcus aureus and Escherichia coli were investigated. It was found that SA exhibited significant antibacterial activities and total antioxidant capacity.

Abstract: Normal production of open-pit mine is directly affected by the safety of slope, especially in deep open-pit mine. According to the real conditions of Jinduicheng Molybdenum Open-pit Mine and considering slope stability influential factors such as rock properties and geological structures, slope geometry parameters, groundwater, blasting activities and others, a fuzzy synthetic evaluation model of slope stability is established, which involved membership functions and multi-level weight distribution method. The evaluation model was applied to the slope of Jinduicheng Molybdenum Open-pit Mine, and the results showed that the slope of the mine was general stable at present.

Abstract: The polycarboxylate-type superplasticizers (PCS) modified by sulfonic group were prepared. The influence of sulfonic group content on the performance of cement admixtures when using sulfonic group modified PCS was discussed. Some physical properties such as dispersion, cement paste fluidity, mortar fluidity, compressive strength ratio and flexural strength ratio were investigated. The results show that when using PCS with sulfonic group content 20%~25% (mol/mol of total carboxyl group), the dispersion and fluidity of concrete can be distinctly improved, meanwhile the strength properties can be maintained.

Abstract: Several representative solvents classified in three categories: 1) aprotic apolar solvents: 2) protic solvents; 3) aprotic polar solvents were chosen to investigate the effect on the catalytic activity and selectivity for the selective hydrogenation of 3,4-dichloronitrobenzene (3,4-DCNB) over Pd/C catalyst. The solvent polarity increases the hydrogenation rate apparently, but also increases the selectivity to 3-chloroaniline and 4-chloroaniline from dehalogenation reaction. The solvents with the high polarity and hydrogen-bond donation capability can generate the strong interaction and the H-bond with nitro group of 3,4-DCNB, and then promote the activation and polarization of nitro group. However, on basis of the result of water as solvent, the higher hydrogenation rate in polarity solvents, to a larger extent, may be attributed to the increase of the amount of reactive chemisorbed hydrogen resulting from the dissociative chemisorption of aprotic polar solvents over the activated metal surface. At the same time, this is why the selectivity to 3-chloroaniline and 4-chloroaniline from dehalogenation reaction increase obviously with the increase of solvent polarity, because the amount of reactive chemisorbed hydrogen on the catalytic activated sites exceeds the needs of nitro group reduction and then surplus hydrogen reacts with the C-X bond.

Abstract: _{Subscript text}An adsorbent has been prepared from Heishan coal by chemical activation with KOH, the activated carbon has a BET surface area of 801.53 m2/g, the meso-pore ratio is 89.63%, SEM image shows that it is very rich in pore structure. The activated carbon was used to adsorb malachite green from an aqueous solution in room temperature. The effects of pH, contact time and dosage have been studied. The results show that the adsorption of malachite green from aqueous solution onto Heishan coal-based activated carbon proceeds according to the pseudo-second-order model, the adsorption equilibrium data were better represented by the Langmuir isotherm than Freundlich isotherm.

Abstract: Cedar sawdust (Cedrus deodara), an agricultural by-product abundant in China, was used as an adsorbent for the removal of Cu(II) from aqueous solutions. The extent of adsorption was investigated as a function of pH, contact time, adsorbate concentration and reaction temperature. The Cu(II) removal was pH-dependent, reaching a maximum at pH 5. The adsorption process followed pseudo-second-order kinetics and equilibrium was reached at 60 min. The rate constantly increased with the increase of temperature, indicating the endothermic nature of adsorption. The equilibrium adsorption capacity of Cu(II) determined from the Langmuir equation was 64.52 mg/g at 25°C. The equilibrium data fitted very well to the Freundlich isotherm model as compared to the Langmuir isotherm. The negative ΔGo values at various temperatures confirm that the adsorption processes are spontaneous. Attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR) analysis of cedar sawdust, before and after adsorption of Cu(II), suggested that the main mechanisms involved in the removal of Cu(II) might be the ionic exchange and complexation.

Abstract: The filtration technology is studied through the reproduce of wasted lube. The suitable temperature of the filtration operation is 60°C -90°C for filtering by measuring the temperature-viscosity curve, which provides the basis for wasted lube filtration technology.

Abstract: A novel enrichment and detection method for 6 kinds of main polychlorinated biphenyls(PCBs, PCB 28;2.PCB 52;3.PCB 101;4.PCB 153;5.PCB 101;6.PCB138) monomers was established. Target compounds were extracted by n-hexane/ methylene chloride (v/v,1:1) and methylene chloride, then enriched by rotary evaporator and purified by sulfuric acid. The detection signals were enhanced in the presence of different concentrations for the six kinds of PCBs from1 to 100 ng/mL with the coefficient of derivatives between 0.996 and 0.999. Recoveries of spiked tissues prepared with this method ranged from 76.7% to 106%, and the relative standard deviations (RSD) ranged from 4.0% to 11.1%. The method was used to extract PCBs from fish samples and determination of 6 kinds of main PCBs species with good accuracy and reproducibility.

Abstract: The hydrolysis product was prepared by added-seed thermal hydrolysis method with industrial titanyl sulfate solution. The influences of some factors (such as preheating temperature, sodium hydroxide concentration and activity of seeds) on the particle size and particle size distribution (PSD) of hydrolysis product were studied. The product was characterized by particle size analyzer and filtering property test. The results showed that all these factors had great impacts on PSD of product and its filtering property, the narrowest coefficient of variation (C.V.) was 43.0% and the fewest filtering time was 311s. The optimal conditions were as follows: preheating temperature was 90°C; NaOH concentration was 8.0-8.5%; activity of crystal seeds was 100-140 mL.

Abstract: The inhibitive synergistic effect between a cationic gemini surfactant, 1,2-ethane-bis(dimethyl dodecylammonium bromide) (designed as 12-2-12), and anionic surfactant, sodium dodecyl sulfonate (SDS) for the corrosion inhibition of A3 carbon steel in 1 mol L-1 HCl was investigated by weight loss. The inhibition system composed by 12-2-12 and SDS is efficient. The adsorption mechanism of the 12-2-12 and SDS on steel in acidic medium is discussed on the basis of experimental data and an adsorption model is proposed. Adsorption of inhibitor system on the A3 carbon steel surface in acidic medium obeys Langmuir’s adsorption isotherm.