Advanced Materials Research Vols. 239-242

Abstract: Due to similar publication in another journal the authors have withdrawn the paper.

Abstract: New Cr-Ni-ZrO₂ composite coatings are prepared by composite electrodeposition. The morphology, composition and corrosion resistance of as-deposited Cr-Ni-ZrO₂ coatings are systematically characterized by means of SEM, EDS. The hardness of as deposited and annealed Cr-Ni-ZrO₂ coatings are also discussed. The electrochemical corrosion tests are conducted by means of Tafel plots. Results of SEM and EDS show that Cr-Ni-ZrO₂ composite coatings with homogeneous and crack-free morphology have been prepared successfully; the mass proportion of Zr in the as-deposited coatings is up to 7.85%. The hardness values of Cr-Ni-ZrO₂ coatings are higher than that of Cr-Ni alloy coatings. Furthermore, the hardness values increase and then decrease with the temperature increasing when annealed. Analysis of Tafel plots demonstrates that Cr-Ni-ZrO₂ coatings have much better corrosion resistance than that of Cr-Ni coatings.

Abstract: Titanium dioxide (TiO₂) thin film has been successfully synthesized deposited on glass substrates by the sol–gel dip-coating method using freeze drying technique. The precursor and TiO₂ film were characterized using thermogravimetric and differential scanning calorimetric (TG-DSC), X-ray diffraction (XRD) and atomic force microscopy (AFM) analysis technology. The preparation of the precursor sols and TiO₂ film were described in detail. The XRD result demonstrates that the TiO₂ film is well crystallized and consists of anatase phase only with (101) plane. The morphology of the nanoparticles of TiO₂ thin film is spherical shape with grain size of 30.1 nm in average diameter and the surface of the TiO₂ film is smooth. The freeze drying technique offers a novel process route in treating thin film for commercial applications

Abstract: A novel series of hydroxyl terminated bisphenol-A type novolac epoxy resins modified with propionic acid (MEP) were prepared by one-step ring-opening reaction process in the presence of tetramethylammonium bromide catalyst. The obtained MEP was characterized using FTIR, ¹HNMR analyses. In addition, Intercross-linked epoxy-polyurethane composites networks were also obtained by curing reaction among MEP, cross linker polyisocyanate IL1351 and phthalic anhydride. The thermal characteristics of the epoxy-polyurethane composites were determined by thermogravimetric analysis (TGA). The thermal stability of the cured MEP with different ring-opening rate and cured alkyd polyol A450 were compared. The results showed that the obtained epoxy-polyurethane composites had much better thermal stability than the conventional polyurethane system A450/IL1351, and the thermal stability of them was correlated to the content of MEP.

Abstract: Ionic liquid-functionalized SBA-15 (IL-SBA-15) was prepared by cocondensation of functionalized ionic liquid (IL) and tetraethoxysilane. IL was firstly synthesized using microwave and the experimental parameters were optimized. Furthermore, IL-SBA-15 was introduced into the fabrication of electrochemical sensors. It was found that these sensors exhibited good performance to the simultaneous determination of dihydroxybenzene isomers or metal ions. The good sensitivity and stability presented the promising application of IL-SBA-15 in the application of electrochemistry.

Abstract: Transparent conductive Cu-In-O thin films were deposited by reactive DC magnetron sputtering. Two types of targets were used. The first was In target covered with a fan-shaped Cu plate of the same radius and the second was Cu target on which six In grains of 1.5mm was placed with equal distance between each other. The samples were characterized with scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), UV/VIS spectrophotometer, four-probe measurement etc. SEM shows that the surfaces of all the samples are very smooth. EDX shows that the samples contain Cu, In as well as O, and different targets result in different atomic ratios of Cu to In. A diffraction peak related to rhombohedra-centered In₂O₃ (012) is observed in the XRD spectra of all the samples. For both the two targets, the transmittance decreases with the increase of O₂ flow rates. The direct optical band gap of all the samples is also estimated according to the transmittance curve. For both the two targets, different O₂ flow rates result in different sheet resistances and conductivities. The target of Cu on In shows more controllability in the composition and properties of Cu-In-O films.

Abstract: Copper and copper alloys had various applications in tremendous areas due to their unique properties, such as good conductivity, good thermal conductivity and so on. However, applications of copper and copper alloys were severely restricted as the result of the limited strength at room temperature and poor wear-resistance at high temperature. In this paper, we investigated the preparation of Cu-Cr-Zr/AlN nanocomposites by mechanical alloying process and then powder metallurgy technology. XRD and SEM were performed for the phase and morphology characterization. The conductivity properties were also tested and the results showed that Cu-Cr-Zr/AlN nanocomposites exhibited excellent conductivity behavior.

Abstract: In allusion to the shortage of the traditional multilayer structure of urea reactor, a new type of the integrated multilayer wounded structure with a stainless alloy lining was put forward. The characteristics of this new type of urea reactor structure was recounted, the manufacture and development as well as its main achievements were narrated simply. Moreover, its manufactural process and the examples in engineering applications were introduced, and the reliability and foreground in urea industrial production were also analyzed and forecasted.

Abstract: Polysiloxanes containing cyanoethyl groups (PDMS-CN) is a useful functional polysiloxanes. In this paper a new method was employed to prepare the polysiloxane with various number average molecular weight (Mn) and cyanoethyl groups. Mns of PDMS-CN were determined by GPC and the relationships between the instrinsic viscosity ([η]) and Mn of PDMS-CN were given. The contents of cyanoethyl groups were determined by FT-IR and ¹H NMR.

Abstract: Since phase change energy storage exchanger has two functions of heat exchange and heat energy storage, it is an important component of heat energy storage technique with phase change materials, its research has been thought highly by people, and great achievements have been obtained during the recent years. A review on its various structures and their research and development was made in this paper, and its further research and applications were also analyzed and forecasted.