Advanced Materials Research Vols. 881-883

Abstract: The dynamic characteristics of the piezoelectric materials are demonstrated by the ANSYS finite element techniques. Based on the analyses of the modeling results of the monolayer piezoelectric materials, the dynamic characteristics of the multi-layer piezoelectric pile are further investigated. For piezoelectric materials with a certain thickness, it is found that the resulting stroke and output increases with the decrease of the layer thickness which is attributed by the increased layers and substantially unchanged overall-stiffness.

Abstract: Organic light emitting diodes (OLEDs) have the potential to compete with other rivals in applications of lighting and small size displays because of low power consumption. To achieve commercial standard, however, the luminance efficiency and device lifetime of the OLEDs still need to be improved. This work characterizes the performance of OLEDs improved by Poly (3,4-ethylenedioxythiophene) poly (styrenesulfonate) (PEDOT:PSS). PEDOT:PSS films are deposited on ITO glass by spin coating at the first, and then the hole transporting layer and electron transporting layer of the OLED materials N, N '-bis (naphthalene-1-yl)-N, N '-bis (phenyl) benzidine/tris-(8-hydroxyquinoline) aluminum (NPB/Alq₃) are thermally evaporated with 1 Å/s deposition rate. The thickness effects of the PEDOT:PSS on the OLED performance are studied. The result shows that PEDOT:PSS effectively improves the luminance of the OLEDs, where 40 nm thick PEDOT:PSS increases 12% and 30 nm thick increases 31% luminance, respectively. Furthermore, the effects of the PEDOT:PSS on the mechanical properties of the OLED are also studied.

Abstract: The calcium peroxide microparticles were synthesized and evaluated as an innovative oxidant to pretreat glyphosate wastewater. The CaO₂ microparticles were 0.1-0.3 μm in diameter and the average CaO₂ content was 80%. Experiments were performed to investigate the influence of m(CaO₂ :COD_Cr), n(CaO₂:FeSO₄·7H₂O), pH and contact time of solution on the removal efficiency of TP and COD_Cr. Under the optimal condition (m(CaO₂ :COD_Cr) =1:1, n(CaO₂:FeSO₄·7H₂O)=4:1, pH=3.0,contact time =30min), the removal efficiency of TP and COD_Cr reached 94.2% and 62.1% respectively. These results suggested that CaO₂ microparticles may be used to develop a simple and efficient pretreatment method for glyphosate wastewater.

Abstract: It is an effective solution to the problem of agglomeration using the magnetic composite SiO₂/(γ-Fe₂O₃- SiO₂) instead of traditional magnetic particles Fe₃O₄ as the core of molecular sieve. The traditional hydrothermal method was utilized by means of adding the magnetic composite particles SiO₂/(γ-Fe₂O₃- SiO₂) into the pre-made crystallization liquid. Then, a series of magnetic 4A zeolites with varying contents of SiO₂/(γ-Fe₂O₃- SiO₂) were synthesized under the condition of ultrasonic crystallization for 6 hours with the power of 100W and temperature of 70 °C . Afterwards, the characterization tests such as XRD,SEM,TG,IR were carried out; the final result showed that the performance of 4A zeolite molecular sieve with SiO₂/(γ-Fe₂O₃- SiO₂) is basically identical with the pure 4A zeolite molecular sieve. The absorption rate was 13.5927μg/g by using the 4A zeolite molecular sieve with SiO₂/(γ-Fe₂O₃- SiO₂) for the absorption of mercury. Key words: 4A zeolite molecular sieve; magnetic composite; silver loaded;Demercuration

Abstract: Chitosan (CS) film prepared by casting-evaporation method, was processed by alkali leaching. Structural characterizations of CS film before and after alkali leaching were measured by Fourier transform infrared reflectance spectroscopy, X-ray diffraction. Effect of alkali leaching to thickness, mechanical properties, water contact angle, water-solubility and swelling index of CS film were investigated. The results manifested that CS acetate was converted to CS through alkali leaching. Vibration intensities of covalent bonds was decreased by alkali leaching. After alkali leaching, thickness, water-solubility and swelling index of CS film decreased, meanwhile tensile strength, elongation at break and water contact angle of CS film increased. Mechanical properties and waterproofness of CS film was improved by alkali leaching. The research results could provide theoretical basis for the application of CS film after alkali leaching.

Abstract: Florida mandarin oil-chitosan composite films were prepared with chitosan (CS), Florida mandarin oil (FMO) by casting-evaporation-alkali leaching method. Influences of FMO to mechanical properties, water contact angle, water-solubility of films were evaluated. The results demonstrated that decrease of film tensile strength was caused by addition of FMO. When FMO content was 4%, elongation at break reached the maximum (2.81±0.01%). Water contact angle and solubility of film increased with increase of FMO content, maximums were 81.80±0.09° and 1.51±0.02 mg/100 g H₂O, respectively.

Abstract: Cation and anion exchange membranes were prepared by radiation-induced graft polymerization of ethyl styrenesulfonate and chloromethyl styrene, respectively, onto poly (ethylene-alt-tetrafluoroethylene) (ETFE) films, followed by hydrolysis in the former case and quaternization in the latter case. The degree of grafting as well as the ion exchange capacity (IEC) and the conductivity of the prepared membranes were investigated. Furthermore, the cation and anion exchange membranes were tested in an electrodialysis cell using CsNO₃ aqueous solution in the dilute compartment. It was found that the high-IEC membranes enhanced the electrodialysis speed, while the low-IEC membranes showed the high percent removal.

Abstract: The physical and chemical properties of stalk fiber extracted by different method was important for the characters of the product. And the research laid the foundation for the complex utilization of eggplant stalk.Morphology of eggplant stalk fiber was determined by Feica microscope, the length, width and length to wide ratio were analyzed by SPSS 17.0. Chemical compositions different analysisof eggplant stalk fiber extracted by mechanical process were analyzed by applying Block test method with Design-expert 6.0.10.The result present that length, width, and length to wide ratio of stalk fiber were 11 mm,1338 um,20,respectively. Cellulose content of eggplant stalk was 34.31 %, hemi-cellulose content was 11.03%, lignin content was10.69 %.Cellulose content of eggplant stalk fiber was 36.2 %, hemi-cellulose content was18.55 %,lignin content was 17.49%.Hemi-cellulose increased by 7.52 %, cellulose increased by1.89 %, lignin increased by 6.8 %.The composition of fiber had significant difference.Beating degree was positively correlated with the beating time, beating time and wet weight were a negative correlation. Strength of stalk fiber was positively with the gramme, and strength was8.3N when gramme was 60 g/m2.

Abstract: The present paper focused on the use of the salt of rare earth cerium as corrosion inhibitor of Zinc by using cathodic electrolytic passivation method. The corrosion resistance and the microphology of the cerium passivation film were studied by the methods of electrochemical method, scanning electron microscopy (SEM). From the results, it was shown that good corrosion resistance of cerium-based trivalent chromium conversion coating was obtained when the compositions were as follows: Ce (SO₄)₂, 6g/L; Cr₂(SO₄)₃, 18.9g/L and NaNO₃; current density, 2A/dm²; temperature, 40 oC; time, 60s. SEM revealed that the cerium trivalent chromium conversion coatings formed uniform cerium hydroxide and chrimuim hydroxide deposition on the surface of Zinc.

Abstract: The effect of season factor on the performances of poly (vinyl alcohol)/rice straw (PVA/RS) composites prepared by hot-pressing was studied. Two forms of RS, including shortcut RS and RS wires, were used to prepare composite. For PVA/ shortcut RS composites, samples of winter showed higher tensile strength and strength at tensile fracture at different PVA contents than that of summer. When PVA content is 50%, tensile strength of winter sample is 136% higher than that of summer sample and strength at tensile fracture of winter sample is 320% higher than that of summer sample. In addition, samples of winter showed lower tensile stretch and higher hardness at different PVA contents than that of summer. For PVA/RS wire composites, the comparison results are similar. These indicated that season is an important factor for preparing plant based composite with PVA as adhesive.