Advanced Materials Research Vols. 239-242

Abstract: Magnetorheological elastomers are a new kind of MR materials, which consist of magnetizable particles and elastomers. Because of the controllable orheological properties, the materials show a widely prospect in engineering application. In this paper, the magnetic-induced modulus under shear-compression mode was studied. Based on the modulus, the relative MR effect and its influence factor were systematically analyzed. The results show that the relative MR effect will increase with the increasing volume fraction of magnetizable particles, the exterior magnetic field strength and compression strain, and decrease with the increasing shear strain and modulus of matrix. For the study of the relative MR effect, it will give useful advices for the design of MR materials and MR devices.

Abstract: This paper studied the mechanical behavior of the filament/staple fiber composite yarn and the pure cotton yarn under the isostress and isostrain of cycling tensile strength with the conditions of small deformation. And it also analyzed the elastic recovery rate, creep rate and stress relaxation rate under the different deformation rate and load. The results show that the mechanical properties of elastic recovery rate, stress relaxation and creep all keep in good range in the experiment of cycling tensile strength with low certain elongation and constant load; as the increase of certain elongation and constant load, the mechanical properties of elastic recovery rate, stress relaxation and creep have much difference, just in terms of the conformality under the cyclic tensile strength, PET/PU/cotton composite yarn shows the best, next is the PU/cotton composite yarn, and then next is the PET /cotton composite yarn, and the pure cotton yarn shows the worst.

Abstract: In this paper, a piezoelectric quartz crystal (PQC) sensor has been developed with a coating material of N, N, N’, N’-tetrakis (2-hydroxyethyl) ethylenediamine (THEED). The active compound was selected from fifty-one adsorptive coating materials and was the most efficient one for sensing of carbon dioxide gas. The coated PQC sensor possessed an excellent linear response range of 0.3738 ~ 31.85% with a sensitivity of 53.81 Hz/% to CO₂ gas after coating with 91.62 μg of THEED. The detection limit for CO₂ gas could reach 100.0 ppm. The sensor also possessed good reproducibility and stability. There were no significant interferences from other gases dissolved in transformer oil such as carbon monoxide, hydrogen, methane, ethane, ethylene, and ethyne. The THEED coated PQC sensor has been successfully applied to the determination of CO₂ samples dissolved in transformer oil, showing its promising application for generation set’s safety evaluation in power industry.

Abstract: Proton exchange membrane is one of the most important components for proton exchange membrane fuel cells (PEMFCs). The preparation of proton exchange membranes based on sulfonated polyimide (SPI) for PEMFCs in recent years was reviewed, and methods of improving the water stability and proton conductivity of such membranes were highlighted. It was suggested that preparation of novel SPI membranes or organic-inorganic composite SPI membranes should be a reasonable approach to strengthen their combination property.

Abstract: BaFe_12-2xMn_xSn_xO₁₉ was synthesized by an improved co-precipitation method. Scanning electron microscopy images were characterised. The synthesis efficiency is discussed from the structure fundaments.

Abstract: HBWSL-1 type photosensitive resin for Stereolithography was prepared with bisphenol A type epoxy diacrylate (EA-612), polyethene glycol (200) diacrylate (PEGDA), ethoxylated trimethyolpropane triacrylate (EO₃TMPTA), cycloaliphatic diepoxide (ERL-4221), polycaprolactone polyol(Polyol-0301), 1-hydroxycyclohexyl phenyl ketone (Irgacure184) and a mixture of triarylsulfonium hexafluoroantimonate salts (UVI-6976). The main parameters of the photosensitive resin were as follows: the penetration depth was 0.15mm, the critical exposure was 16.6mJ/cm², the viscosity at 30°C was 215mPa.s, and the density at 30°C was 1.13g/cm³. With the photosensitive resin as the processing material, cuboid parts and double-cantilever parts were fabricated by using a stereolithography apparatus, and the dimension shrinkage factor and the curl factor were studied. The shrinkage factor was less than 1.00%, and the curl factor was less than 8.00%, which showed that the accuracy of the fabricated parts was high with the photosensitive resin for stereolithography.

Abstract: White organic light emitting devices with the structure of ITO/ MeO-TAD (15 nm) /NPBX(40 nm) /DPVBi(x nm)/ Rubrene(0.3 nm)/DPVBi (20-x) nm /BCP(5 nm) / Alq3 (30 nm) /LiF(0.5 nm) /Al. High-mobility MeO-TAD is added into the region between ITO and NPBX to increase hole injection and transport. The BCP layer was used as the hole blocking layer .In the meanwhile, an effective carrier balance (number of holes is equal to number of electrons) between holes and electrons is considered to be one of the most important factors for improving OLEDs. During the experiment, by modulating the thickness of DPVBi , we can control hole injection and electrons transport to make the carriers reach a high-level balance. The maximum current efficiency was 1.22 cd/A.

Abstract: BaFe_12-2xMn_x/2Co_x/2Sn_xO₁₉ was synthesized by an improved co-precipitation method. Magnetic Properties of the products were characterised.

Abstract: Cr-Fe-ZrO₂ composite coatings were electrodeposited in trivalent chromium chloride electrolyte containing glycine as complexing agent. The effects of electrodeposition parameters such as current density and electroplating time on appearance, surface morphology and composition of the Cr-Fe-ZrO₂ composite coatings were investigated mainly. The obtained Cr-Fe-ZrO₂ composite coatings were characterized by means of scanning electron microscope (SEM) and energy disperse spectroscopy (EDS) techniques; the appearance quality was evaluated by range estimation; and the bonding force was analyzed by bending tests. The SEM results showed that the nano-size ZrO₂ powder were fairly distributed through out in the composite coating, and the composite coating contained only few fine cracks. The EDS results indicated that the composite coating contained chromium, iron, zirconium, oxygen, carbon and chlorine. The deposited coating was glossy and the results of bending tests showed that the bonding between the composite coating and the substrate was good

Abstract: The effects of rare earth elements (RE) on corrosion behavior of Q345B steel at marine atmospheric environment in Compact strip production (CSP) technology was studied using alternate immersion test in this paper. The influences of RE on the microstructure, the components of corrosion products, the corrosion dynamic laws as well as the electrochemical properties were also investigated by optical microscope, SEM, XRD, polarization curve and EIS measurements. The results show that the microstructure of Q345B steel in CSP is finer and the corrosion is mitigated due to relatively compact corrosion products with the addition of RE. The corrosion current density of Q345B steel with RE is lower than that of Q345B steel without RE and the corrosion resistance of Q345B in CSP is improved to a certain extent by RE.