Papers by Keyword: Dipping Method

Abstract: Waste coal fly ash was used, as a cheap and handy material, to synthesize zeolite.The synthesized zeolite was then taken, as a carrier, to load CuO by dipping method for heterogeneous catalytic wet oxidation of acid bright red GR wastewater. The optimal process parameters of CuO loading were determined by orthogonal test. The comparison of XRD patterns of zeolite and CuO/zeolite displayed that CuO was successfully loaded on the zeolite.The SEM morphology of CuO/zeolite revealed that the cotton shape structure with more loose surface of CuO/zeolite was obtained compared with the SEM morphologies of fly ash and synthesized zeolite. The experimental results of water treatment showed that high COD_Cr and chroma removal rates of 88.27% and 99.97% were achieved by the prepared CuO/zeolite sample,respectively.

Abstract: In this study, an effect of leaching treatment on the mechanical properties of natural rubber latex (NRL) products was investigated. The products were prepared by compounding the NRL dispersion system with modified kaolin as fillers then it was formed by dipping method. It was found that incorporation of fillers in NRL would result in lowering mechanical properties of vulcanizates when the leaching was performed. The results were confirmed further by characterization of Fourier-Transform Infra-Red (FTIR) and Scanning Electron Microscopy (SEM).

Abstract: Ribbon silicon material is specially designed for solar cell wafers. In this paper, a novel ribbon silicon material “dipping method” has been designed in order to lower the cost of solar cell. The principle and procedure of dipping method were described. In addition, the diffusion of impurities in the silicon wafer and its influence on the efficiency of solar cells were investigated. The photovoltaic performance of polycrystalline silicon solar cells which were based on the metallurgical grade silicon substrate with the thickness of 600μm, was simulated by AMPS1-D software. And some import parameters were obtained including I-V characteristic, 17.004% conversion efficiency. This artic is provided theoretical support to the industrial production of solar cells by dipping method, and it will open a new road to production low cost solar cell.

Abstract: Solution growth was performed using a free-standing (001) 3C-SiC epilayer as a seed crystal at a growth temperature of 1700°C. The seed crystal was prepared by a CVD method on the undulated Si substrate. 3C-SiC stably grew on the (001) seed crystal. However, dark stripes from the seed crystal to the grown crystal along {111} planes were clearly observed. The stripes were due to the high-density stacking faults extended from the stacking faults in the 3C-SiC epilayer that were induced during the CVD growth on Si substrate.

Abstract: Mullite film was formed on ß-SiAlON (Si6-zAlzOzN8-z, z = 3) ceramics by reaction of Al2O3 films with silica formed on oxidation to improve a high temperature water vapor corrosion resistance. Sintered ß-SiAlON was fabricated by hot pressing of ß-sialon (z = 3) powder without additive at 1900°C and at 24 MPa for 4 h in N2. The Al2O3 film was deposited on polished ß-SiAlON ceramics by a dip coating process of Al2O3 precursor sols prepared from the alkoxide solution and aluminum sol. The Al2O3 coated sample was heated in Ar/O2 (95/5 vol.%) at 1300°C for 2 h, resulting in the formation of mullite by reaction with silica produced from sialon. The resulting mullite-coated sample was corroded in H2O/Ar/O2 (90/8/2 vol.%) at 1200°C for 2 ~ 100 h. The corroded samples were characterized by XRD and SEM-EDS for the evaluation of the corrosion resistance of mullite-coated sialon.

Abstract: Stents are special metallic or polymer endoprostheses of meshed structure and tube shape. Their function is to prevent restenosis in the arteries. Stents can be coated or uncoated. In the expanded part of the artery the chance of restenosis is bigger even without a stent so it is practical to coat the stents. The aim of this work is to present the results of the coating experiments made on the coronary stents. Three types of commercially available polyurethanes were used for these experiments. The coatings were produced by a dipping method. Electro-polished and non-electro-polished metallic sheets and stents were used for these experiments. Contact angle measurements were done to examine the wetting properties of the three different polyurethane coatings. The quality and the changing of the coatings were examined by different methods (stereomicroscope, scanning electron microscope and energy dispersive spectrometry).

Abstract: For the investigation of high aspect ratio structures with Atomic Force Microscope (AFM), the cantilevers with very sharp and long tips are useful. Electron beam induced deposited(EBID) tips can be simply fabricated by aligning the electron beam directly down the vertical axis of Si cantilever and then irradiating a single spot on the cantilever for a proper time in the dominant atmosphere of residual gases generated by the oil of the diffusion pump of the Scanning Electron Microscope (SEM). However, the EBID tips cannot grow over 1&m in the residual gas atmosphere since there is a little carbon source. We could enhance the height of tips by dipping the cantilever into the organic solvents, drying it in the vacuum chamber and irradiating electron beam on it. With this process, we could acquire the tip whose base diameter is 180nm and effective length is 3.18&m. In addition, we observed that the growth behaviors of the tips are different in accordance with the species of the solvents and we will discuss the effects of the organic solvents on the growth of the tips.