Materials Science Forum Vols. 610-613

Abstract: The method of wettability of solid-liquid interface is used to examine the differences of the liquid membranes formed by hydrophilic or hydrophobic membranes with different size and different materials, the influence of the characteristics of membrane modules in the process of desulfurization is studied. The method of accelerating the renewing rate of liquid membrane is proposed. The results show that the hydrophobic liquid membrane leads to higher renewing rate and absorption efficiency of sulfur dioxide and the hollow fiber membrane of polypropylene has higher adsorption efficiency. The dynamic contact angle of the same hollow fiber membrane is increasing with the number of the fibers leading to the increase of the diffusing resistance of liquid between the fibers. In order to accelerate the renewing rate of the liquid membrane, the concentration of the medium should be decreased under the condition of high absorption capacity.

Abstract: Water Storage and Controlled-release Film (WSCF) material is a kind of composite film which can form a “small reservoir” in the soil to meet the need of plant growth when packed with water and embedded in soil around tree roots. Coated water-transmitting fiber is a kind of functional fiber which has effect of transmitting water in WSCF material. Different coated water-transmitting fibers were prepared by treating natural fiber using colloidal composite materials made of polyvinyl alcohol and inorganic clay such as Common clay, Kaolin or Bentonite. Furthermore, the water-transmitting capacity and surface morphology of coated water-transmitting fibers were studied by thermal multi-analyzer, instrument for quick moisture measure and SEM. The results show that coated water-transmitting fiber with continuous and compact surface has better water-transmitting capacity than those with uneven surface and the addition amount of clay also can affect the water-transmitting capacity of coated fiber. Additionally, coated water-transmitting fibers can regulate water transferring according to the variation of temperature or soil humidity.

Abstract: This paper aims to design a sort of aqueous atomization absorbing material which can absorb mine gas under coal mine to decrease the methane concentration and reduce the explosion hazard. The material was composed of water as matrix, Span 80 as methane absorbent, and inorganic salt as additive. Methane the main component of mine gas was used as model of mine gas. The influence of concentration of inorganic salt on absorption and the effect of different compound materials made of Span 80 and inorganic salt on absorption were studied using Head Space Gas Chromatography to determine the content of methane absorbed. Explosion chamber was used as experiment system to simulate mine gas explosion. The explosion suppression effects of absorbing materials were studied preliminarily in explosion chamber using the maximum explosion pressure and residual methane content after explosion as parameters. The results indicate that the absorbing material can absorb more methane than water and can partly inhibit the explosion of the mixture of methane and air.

Abstract: To evaluate the acute lung toxicity of intratracheally instilled nano-titanium dioxide (TiO2) in Kunming mice, healthy adult Kunming mice were randomly grouped by their body weights (5 mice in each group). The lungs of mice were intratracheally instilled with 1 mg/kg•bw or 10 mg/kg•bw of nm-TiO2. The control group was intratracheally instilled the same volume physiological brine. After exposure of 1, 7, 14 and 28 days, the bronchoalveolar lavage (BAL) fluid and lung tissue were collected. The indexes in BAL fluid were examined. Lung tissues were assessed by histopathology. The results showed that all indexes of 10mg/kg•bw groups were obviously higher than those of the control group and the group of nano-1mg/kg•bw. Activities of LDH on the 1st, 7th, 14th and 28th day post-exposure (pe), contents of MDA on the 1st, 7th and, 14th day pe and TP on the 1st and 7th day pe as well as the amount of leukocyte on the 1st and 7th day pe of 10mg/kg•bw groups were significantly different compared with control groups (P<0.05).There were no obvious changes observed in the activity of ATP within groups (P>0.05). Histopathology found that lungs of 10mg/kg•bw groups presented great increase in pulmonary inflammation. Many TiO2 particles were still clearly found in the interstitium at 28 days pe. In contrast, low-dose instillation had a low risk potential for producing adverse pulmonary health effects. We conclude that the inflammatory reaction gradually eased after 28 days pe. Under the same experimental condition, the effect of lung injury was severer in high-dose nano-TiO2 than low-dose nano-TiO2.

Abstract: Polymeric compounds are of great interest as corrosion inhibitors in acidic environment due to their inherent stability. Polymeric film is effectively used for the protection of metals partly owing to their capacity to act as a physical barrier between the metal surface and the corrosive environment. In this paper, a cation polyelectrolyte inhibitor (Quaternary Polyethyleneimine, QPEI) was prepared. The quality and inhibition efficiency of QPEI self-adsorbed films were studied by polarization curve and electrochemical impedance spectroscopy, respectively. The compositions and morphologies of the polymer film on the steel surface were examined with the aids of SEM and XPS, respectively. The results showed that QPEI could greatly retard the corrosion of iron in sulfuric acid, which was attributed mainly to the protective QPEI film formed on the surface. Meanwhile, the inhibition of QPEI could be supposed as a mixed process, in which both cathodic and anodic corrosions were simultaneously restrained. Based on the results of XPS and SEM, it could be evidenced that the QPEI can form a protective polymer layer on the metal surface by adsorption.

Abstract: This presented a route to utilize the Tungsten Molybdenum Bismuth Polymetallic Tailings in Shizhuyuan of Hunan province to fabricate Ca-substitued α-Sialon eco-materials. The reaction mechanism in carbothermal reduction nitridation process was widely studied by separately considering the effect of sintering temperature and soaking time. Based on the optimized conditions, a composite containing 78% Ca-based α-Sialon has been fabricated at 1600°C for 8h.

Abstract: Titanium dioxide (TiO2) thin film was fabricated on the surface of glass monolayers at room temperature, using KH-550 as self-assembled monolayers (SAMs). The TiO2 gel precursor was characterized with differential scanning calorimetry – thermogravimetry (DSC-TG), and the TiO2 powder was analyzed with X-ray diffraction (XRD). The TiO2 thin film was tested with X-ray fluorescence spectroscopy (XRF). With the application of atomic force microscope (AFM) the surface topography of siloxane layer and TiO2 film were studied. Their hydrophilicities were measured. The transmittance of TiO2 film was detected by using dual beam ultraviolet - visible spectrophotometer. The results show that the TiO2 thin film is in monolayer with nanometer level, the deposition is the anatase structure. TiO2 is deposited on the surface instead of channel or gap of siloxane, the hydrophilicities of TiO2 monolayer film are perfect, and TiO2 monolayer film has a good transmissivity in the visible light area.

Abstract: The effect of the thermal treated red mud on mechanical properties of loess –containing aluminosilicate based cementitious materials is investigated. And the characteristic of hydration production is tested using XRD, SEM and EDAX methods. The results show that the thermal treated red mud not only has excellent cementitious properties but also can improve the mechanical properties of loess –containing aluminosilicate based cementitious materials. Moreover when the content of red mud is 5%, the improved effect is optimal. On the one hand, the alkaline ingredients of red mud can promote abundant ettringites to produce at early ages. And the ettringites contribute to early strength of the cementitious material. On the other hand, the content of red mud is too high to improve the long-term strength.

Abstract: A ferric stearate electrode was made by doctor-blade methods using the Fluorine tin oxide (FTO) conductive glass. The electrochemical behavior of ferric stearate electrode was studied by the cyclic voltammetry. The electro-catalytic effects of ferric stearate on H2O2 were also investigated by cyclic voltammetry.

Abstract: Surface modification is very important to industrial application of the magnesium hydroxide (MDH) powder, which is used as a kind of environment-friendly flame-retardant. In this paper, a kind of MDH powder surface-modified with silicane coupling agent and stearic acid is synthesized, and its potential usage in the flame-retardant treatment of flexible PVC is studied. The influence of the surface treatment to the dispersion of the powder in PVC, the flame-retardant and other physical properties of the MDH flame-retardant treated flexible PVC are discussed in detail. The surface modification mechanism of MDH is studied by the FTIR analysis, and then the surface modification model is established. Results show that molecules between the surface of the particle and these two modifiers form stable chemical bonds, and this kind of surface modification can improve the MDH’s dispersion and the compatibility of the flexible PVC. When the flame-retardant flexible PVC is produced according to the mass composition of PVC/DOP/MDH=100:50:80 and a few other additives, its oxygen index is 31.5, the elongation at break is 240%, the tensile strength is 13.0MPa, the hypothermia tendering is +30/-0, the volume resistivity at 20°C is 3.2×1011Ω•m. These index are just correspondent with requires of the halogen-free fire-retardant flexible PVC.