Advanced Materials Research Vol. 496

Abstract: Ammonia is one of the most important contaminants affecting the quality of water environment. Magnesium ammonium phosphate (MgNH4PO4·6H2O), which is a slow releasing fertilizer, is one possible way to remove high strength ammonia from the wastewater. The wastewater is collected from the effluent of extraction of rare earth elements factory, the study investigate the influence of pH, magnesium and phosphate dosing molar ratio and reaction time for ammonia removal rate. The results show that: when the pH = 9.2, n (Mg): n (N): n (P) = 2.2:1:2, reaction time t = 20min, ammonia concentration of the wastewater from 4420mg / L down to 1440mg / L , ammonia nitrogen removal rate can reach 67%, the remaining TP = 0.9mg / L; higher Ca2 + concentration will affect the MAP precipitation for removing ammonia, but it help to reduce total phosphorus concentrations of effluent; it is not the longer reaction time the better removal rate, because the MAP-formation will destroy with longer reaction time.

Abstract: By using a mixed-solvent solvothermal process, we report a simple and general approach for the morphology controlled synthesis of well-defined ZnS(en)0.5(en=ethylenediamine) rectangular nanosheets. The structure, and morphology of the as-synthesized products were investigated by using XRD, SEM, and TEM. By continuously adjusting the ratio between ethylenediamine and ethylene glycol, cuboid nanocrystals, nanosheets, short nanorods and nanoparticles have been successfully achieved. This conclusive evidence shows that the ratio of solvents played a key role in the morphology-controlled synthesis process. The UV-vis absorption spectrum shows that the morphology evolution provides us an opportunity to structurally modulate physical property, i.e. the energy gap. This simple approach of modulating the physical property promises future application in applied optics, optoelectronic and luminescent instruments.

Abstract: Based on the CAE analysis. The dual variable gear shaft of the transmission for domestic ZL50 wheel loader was redesigned and the processing technology was optimized. The problem of the hardness of the spline which connects the dual variable gear shaft and the working hydraulic pump can not meet the requirements after heat treatment caused by unreasonable design was solved. The problem of the low geometric tolerance and early wear of the spline were solved. After practical application, the market feedback shows that the failure rate, service life and reliability greatly of new designed shaft were enhanced

Abstract: A sensitive aptasensor for detection of L-histidine based on switching structure of aptamer and elongated tetrahexaheral gold nanocrystals (ETHH Au NCs) is presented. The introduction of L-histidine induced self-cleavage of aptamer on the ETHH Au NCs / glassy carbon electrode (GCE) into the solution and the ferrocene (Fc) moiety approached the electrode surface and produced measurable electrochemical signals. With the enhancement effect of ETHH Au NCs, a linear electrical response was observed for concentrations ranging from 1 pM to 0.1 μM, a lower detection limit was 0.1 pM. The proposed approach exhibited excellent selectivity against other amino acids. Such an aptasensor provides a promising strategy for screening other amino acids and toxic ions at ultratrace levels on line

Abstract: The synthesis of protein-like single molecular nano-particle can be simplified by use fewer but longer monomers, which correspond to several old short monomers. The selection of new long monomer subset is optimized and tested in HP model and other models. Results show 2-3 types new monomer are enough to build stable structure, and long monomers should include integer length of one helix, and with interlaced hydrophobic and polar side-chain, thus can form α-helix like structure.

Abstract: Herein, a novel kind of silver nanocluster is synthesized simply by mixing N-Acetyl-L-cysteine template with silver ions and reduction reagent (NaBH4, here). We used fluorescence assay, MALDI TOF MS, and TEM to characterize the silver nanocluster. The complex can be directly employed into bioimaging HeLa cells. The cell toxicity (3-[4,5-dimethylthiazolyl-2]-2,5-diphenyltetrazolium bromide, MTT) assay demonstrated that the silver nanocluster has only little affect on the cytotoxicity to the cells, which further proves the applicability of the method in tumor cell imaging. Our method displays a promising application space in future cancer researches.

Abstract: In this paper, Old Corrugated Container (OCC) was used as the raw material for making paper. The layer-by-layer (LBL) assembly process of creating highly structured thin films was adopted to modify the surface of OCC fibres. Poly dimethyldiallylammonium chloride (PDADMAC) and hydroxyethyl cellulose (HEC) have been used to build up polyelectrolyte multilayers on OCC fibres under a certain condition. Zeta potential analyzer was used to monitor the dynamic adsorption of PDADMAC and HEC with different amount on OCC fibers. Strength measurements of the sheets including tensile index and bursting index were also determined, showing a significant improvement in physical strength with the increase of adsorbed layer number. Compared with not being processed sheets, tensile index and bursting index of sheets from treated fibre with polyelectrolyte multilayers were raised by 36.65% and 49.50%, respectively. Furthermore, filtration time analysis of OCC fibre suspension showed that the built up of PDADMAC and HEC on OCC fibres could improve the fiber-fiber joint strength of joints from polymer-treated fibers, which made the filtration time decline from 30 s to 10.6 s. In addition, SEM was introduced to observe the morphology of the PDADMAC/HEC multilayers. The images revealed that the surface of OCC fibres structured a film like plastic, which could be ascribed to the adsorption layer of polyelectrolyte.

Abstract: In the paper, unbleached bagasse pulp was oxidized with sodium hypochlorite with catalytic amounts of 2,2,6,6-tetramethylpiperidine-1-oxyl radical (TEMPO) and sodium bromide in water. After the TEMPO-mediated oxidation, the oxidized pulp were collected and characterized in terms of morphology, water retention values, crystallinity and deposition properties. The significant changes in morphology were observed before and after the oxidation. Crystallinity of cellulose I was nearly unchanged during the oxidation. Water retention value of pulp can be increased from 68.9% to 70.7% by the TEMPO-mediated oxidation. The TEMPO- oxidized pulp was homogeneously dispersed in water when the pulp consistency is 0.1%.

Abstract: Wind Power prediction is very important in the wind power grid management. This paper introduces how to use Cerebellar Model Articulation Controller(CMAC) to build a short-term wind power prediction model.CMAC and Back-propagation Artificial Neural Networks(BP) are used respectively to do the short-term prediction with the data from a wind farm in Inner Mongolia. After comparison of the results, CMAC is more stable, accurate and faster with less training data.. CMAC is considered to be more suitable to do the short-term prediction. All of the study are based on applied mechanics, which will be useful for energy engineering and mechanics study.

Abstract: The pure β-NaYF4: Yb3+, Er3+ hexagonal sub-microplates were successfully prepared by the combination of coprecipitation and hydrothermal methods using sodium citrate as chelator. The size of them is about 600 nm × 400 nm (side length × thickness). The obtained sample was divided into two parts and one of them was annealed in nitrogen at 300 °C for 2 hours. The crystal structure of the β-NaYF4: Yb3+, Er3+ hexagonal sub-microplates before and after annealing treatment is hexagonal phase. Under the excitation of 980 nm diode laser, the upconversion luminescence intensity the sample after annealing is much stronger than that of the sample without annealing treatment. High temperature annealing process improved the crystallization of the sample, resulting in the decrease of the nonradiative relaxation and the enhancement of the upconversion luminescence.