Advanced Materials Research Vol. 502

Abstract: To study the influence of structure parameters on moisture permeability of fabric woven by fine pp fiber with star section, nine fabrics with different structure and tightness had been woven for experiment, and a moisture permeability test with moisture absorbtion method was performed and compared for these fabrics. Some conclusions are obtained: the moisture permeability showed direct correlation with fabric texture and tightness. It will be improved as the the float of weave get longer. Moreover it will decline with the increasing of fabric tightness and showed significant correlation with Polynomial function when the results fitted with it.

Abstract: The polyaniline(PANI)-poly(vinyl alcoho1)(PVA) composite films with the doping of hydrochloride (HCl), dodecylbenzenesulfonic acid (DBSA) or aminosulfonic acid (NH2SO3H ) were prepared by in-situ polymerization. Effects of PVA content, HC1 content, oxidant ammonium persulfate(APS)dosage, reaction time and film drying temperature on tensile strength of the HCl-PANI-PVA composite film were studied. The conductivity of PANI-PVA composite film with the doping of HCl is the highest of 13.2S.cm-1 among them. The tensile strength of the film is improved greatly due to effective mixture of PANI and PVA. The tensile strength of the composite film substantially depended upon the mass fraction of PVA. The tensile strength of the HC1-PANI-PVA composite film reaches the maximum of 60.8 MPa, in case the PVA content is 40%, the C(HC1)=1.0 mol/L，reaction time is 4.0 h, the n(APS/An)=1.0, and film drying temperature is 80°C.

Abstract: Ammonia water has strong absorption ability for CO2, so ammonia absorption method became an important research direction and has a good application prospect. In this study we designed a simple measurement method and measuring device for carbon dioxide absorption capacity by ammonia. The device is commonly used by a simple instrument assembly and modified. The measurement method is simple and convenient, has strong adaptability, no risk, the data is stability, the results are clear.

Abstract: This study assesses dyeing performance of reactive dyes with monofluorotriazine and modified cvinyl-sulfone bifunctional reactive groups in alkaline/acid denaturalization bath to the soybean fibers. It has been shown that 3~4 of the dyeing pH value, 60 minutes and 70°C of dyeing time and temperature were selected for denatured bath. The denaturalization bath can dramatically improve exhaustion and fixation and significantly decrease the chromaticity of the dyeing effluent. Besides, colorimetric properties, fastness and mechanical strength of the dyed fabrics were evaluated to indicate applicability of this dyeing process of soybean protein fibers.

Abstract: A new red-emitting Rare-earth silicon carbonitrides phosphor, Y₂Si₄N₆C, was prepared by a carbothermal reduction and nitridation method. X-ray powder diffraction (XRD), the photoluminescence excitation and emission spectra, temperature dependent was measured. The emission spectrum obtained by excitation into 410 nm contains exclusively the characteristic emission of Sm3+ at 568, 607 and 654 nm which correspond to the transitions from ⁴G_5/2 to ⁶H_5/2, ⁶H_7/2, and ⁶H_9/2 of Sm³⁺, respectively. The strongest one is located at 606 nm due to ⁴G_5/2 to ⁶H_7/2 transition of Sm³⁺ .

Abstract: The mixture calculation of producing stainless steel crude melts by chromium ore smelting reduction in a 150 t converter is carried out by use of the empirical data and the calculation method of refining plain carbon steel in a converter, according to the blowing conditions of 185 t smelting reduction converter of No.4 steelmaking shop in Chiba Works of JFE Steel. The calculation results show that the required total consumption of chrome ore, coke and limestone in the smelting reduction process is 224.942 kg, 154.9 kg and 99.223 kg, respectively, under the conditions of this calculation. The total amount of slag includes the amounts of hot metal elements oxidation into slag, lining erosion into slag and chromium ore, coke and adding flux into the slag, which is calculated respectively according to the basic raw data and the set values of process parameters. The slag component is confirmed, namely, the actual basicity w(CaO)/w(SiO2)=2.6, the percentage of CaF2 in slag is 3~4 wt%, and the calculated w(MgO)/w(Al2O3)=0.7. In the actual production, the addition of chrome ore, coke and flux is increased by 3%, 2% and 1%, respectively.

Abstract: Microarc oxidation (MAO) coatings were prepared on AZ91D magnesium alloy in a novel dual electrolyte containing various concentrations of sodium citrate (C₆H₅Na₃O₇). The surface and cross-sectional morphologies, coating thickness and surface roughness were characterized by scanning electron microscopy (SEM), layer thickness meter and digital microscope, respectively. The corrosion resistance of coatings was evaluated by electrochemical impedance spectroscopy (EIS). The results showed that both the striking voltage and final voltage decreased gradually with the increase of C₆H₅Na₃O₇ concentration. When the C₆H₅Na₃O₇ concentration increased, surface roughness increased gradually, while thickness of the coating increased at first and then decreased. The coating formed in the electrolyte containing 5g/L C₆H₅Na₃O₇ had a much more uniform and compact microstructure with less micropores and micro-cracks. EIS test showed that the concentration of C₆H₅Na₃O₇ mainly affected the corrosion resistance of inner dense layer, and the coating with best corrosion resistance was obtained in the electrolyte containing 5g/L C₆H₅Na₃O₇.

Abstract: This paper introduces the application of EPC process to the inline-four diesel engine cylinder block production. It includes the make and assembles of foam shape mould, mould design, the choice of sand and modeling, and the design of gating system, etc.

Abstract: At present, the exploited crude oil is about 80% in the presence of crude oil emulsion in the world. More and more research to study stability of the crude oil is developed. Firstly, the basal knowledge of the crude oil emulsion and interfacial film are introduced in this paper. The main reason that crude oil can come into being stable emulsion is it has natural emulsifiers, which can form interfacial film, then the author emphasizes on four natural emulsifiers of the crude oil’s components: asphaltenes, gelatine, paraffine and solid particles, which play very important role in the crude oil emulsion’s stability. The natural emulsifiers, such as asphaltenes, gelatine, can be absorbed between water and oil to form interfacial film that has some visco-elasticity. The stronger is interfacial film, the more stable is the crude oil emulsion.

Abstract: Based on fluid mechanics, the filling process of magnesium alloy step-plate casting molten metal was analyzed, and the filling characteristics were studied by numerical simulating. The results show the filling velocity and the wall thickness of casting have a great effect on the filling characteristics of magnesium alloy. When the filling velocity is less than 0.3 m/s, the liquid frontier of molten metal and the fluid level of thick upper surface fluctuate greatly, and the defects of air entrainment and oxide impurities will appear. When the filling velocity is more than 0.58 m/s, the molten metal fills in turbulent way, and the defects of sputter and air entrainment will appear. The correlation between the wall thickness of casting and the critical filling velocity presented in this paper can be used for the optimization of filling velocity.