Advanced Materials Research Vols. 690-693

Abstract: In this paper, LiOH·H₂O and Li₂CO₃, which were widely used in industry and (Mn_0.533Co_0.233Ni_0.233) (OH)₂ prepared by ourselves selected as starting materials, series materials of lithium-rich layered material Li [Li_0.2Mn_0.44Ni_0.18Co_0.18]O₂ were obtained by a molten salt method. Their structures and properties of the materials were investigated by X-ray diffraction (XRD), Brunauer-Emmett-Teller (BET) and constant current charge/discharge methods. The effects of different LiOH and Li₂CO₃ molar ratios on the Li [Li_0.2Mn_0.44Ni_0.18Co_0.18]O₂ structures and properties were characterized. The results of the experiments indicate that The structures of the material such as crystal structure, the specific area, particle size distribution, tap densities were controlled by adjusting the proportion of the two lithium sources. Forthermore , when the molar ratio of LiOH and Li₂CO₃ was 3:7, the maximum discharge capacity (214.77 mAhg^-1 ) of the cathode was obtained.

Abstract: This paper presents two kinds of direct methanol fuel cell (μDMFC) stack in planar array. The silicon-based DMFC stack is designed in a flip-flop configuration using MEMS technology, and the stainless steel stack is fabricated using stamping technology. Compared to stainless steel stack, the flip-flop silicon-based stack may reduce the connection space and lower the contact resistance between the membrane electrode assembly and the plates. The electrical characterization of this μDMFC stack was carried out by tests. The experimental results showed the prototype was able to generate an open-circuit voltage of 2.7V and a maximum power density of 2.2mW/cm² at room temperature, demonstrating the feasibility of this new configuration. Application of μDMFC stacks as portable power sources were demonstrated using small electric devices powered by this stack.

Abstract: Membrane electrode assemblies (MEA) is the key component of a direct methanol fuel cell (DMFC) and its structure and fabrication technology influenced the performance of DMFC a lot. A novel structured MEA including a hydrophilic inner thin catalyst layer and a traditional outer catalyst layer, provide higher performance. To optimize the combination of the two catalysts layer a mathematical model based on Tafel type kinetics and semi-empirical mass transport coefficient was applied. The simulation of cathode overpotential results showed a DMFC with a 5μm thick inner Pt Blk catalyst layer and an 8μm thick outer 40wt%Pt/C catalyst layer as cathode electrode was the best.

Abstract: Fiber is a new and efficient water treatment and environmental protection material. The key to improve the filtration efficiency of fiber materials is that water pass through the fiber bed, the porous structures of fiber in-depth bed is controlled by the internal construction, fiber arrangement, and fiber zigzag degree. This study presented a method to improve the removal capacity of fiber filtration materials. There are three kinds of porous structures discovered here: Tubular water passage hole (T-pass), Curvilinear water passage hole (C-pass), Labyrinth water passage hole (L-pass). The T-pass let water more easily go through but less sediment and rush strongly off suspensions deposit on the surface of filter materials. The L-pass has resistance to flow and suspension intend to deposit at backside area of filter materials, where not advantage to rush but sediment easily. The function of C-pass is between that of T-pass and L-pass. The experiment shows that C-pass filter bed is the idea structure which can be increased the efficiency of 5-10 times than others.

Abstract: Laccase was selected totreat linen fabric. Such properties of linenfabric were analyzed as weight loss rate, whiteness, breakagestrength, capillary effect, flexural stiffness. The orthogonal test was designedabout pH value, temperature, time and concentration. The factorswere discussed on hemp fabric performance. The optimal process of laccase treatment on hemp fabricis: 50°C, pH4, 25ml/300ml, 50min. Underthe best conditions, hemp fabric weight lossrate 1.87%, breakingstrength 674.7N, whiteness 60.7,flexural stiffness 703.7, capillary effect 8.08cm,wrinkle recovery angle174 º. And the hempfiber’s microstructure changed.

Abstract: The peanut shell was used as the adsorbent of Cr⁶⁺ in this paper. A series experiences have been discussed and studied through the following three aspects, which were the adsorption time, modification effect and contact area. The results showed that the peanut shell for the removal rate of Cr⁶⁺ presented increasing tendency over time. In condition of 25°C, 1.0g unmodified peanut shell,50mL 30mg·L^-1 Cr⁶⁺ solution, the initial pH value 1.0 and contact time 300min, the adsorption rate of Cr⁶⁺ was only 71%. In the same conditions, the removal rate of modified peanut shell was 75%, compared to the unmodified increasing by 4%. Thus modified treatment for peanut shell has no significant effect on the adsorption effect. And In condition of 25°C, 50mL 30mg·L^-1 Cr⁶⁺ solution, the initial pH value 1.0 and contact time 270min, the removal rate of 1.0g modified peanut shell was 75%, but the modified peanut shell powders removal rate was 99%, representing an increase of 25% before crushing, thus to increase the contact area can improve the adsorption effect.

Abstract: Good bonding at the interface between HDPE (High density polyethylene) and wood flour was achieved by adding MA (Maleic anhydride) as surface-reactive additive and WD-50 (3-aminopropyltriethoxysilane) as coupling agent products. HDPE-g-MA was prepared by melt grafting polymerization in the presence of DCP (Dicumyl peroxide) using a Hakke Rheocord. The FTIR spectra conformed that MA was successfully grafted onto HDPE and the effects of DCP and MA contents on grafting reaction were also studied. The effects of silane coupling agent (WD-50), wood flour and HDPE-g-MA contents on the mechanical properties of the HDPE-based wood-plastic composites were investigated by electronic tensile tester and impact test enginery. The results indicated that WD-50 (with the content of 2 wt%) and HDPE-g-MA (with the content of 10 wt%) effectively improved mechanical properties of the composite materials.

Abstract: Calcium sulfate whisker (CSW) was prepared through the method of cooling recrystallization. In an attempt to develop its new application in environmental protection, we investigated the effect of calcination on the material properties and arsenic uptake performance of calcium sulfate whisker anhydrate (CSAW), which was obtained from CSW calcined at 600 °C for 2 h. Moreover, XRD, SEM, optical microscope, and FT-IR were used to characterize CSW samples. It was found that calcination played an important role in the whisker structure through changing the content of crystal water and the morphology. The CSAW material exhibited a high removal rate of As³⁺/As⁵⁺ under strongly alkaline condition.

Abstract: Coal fly ash (CFA) modified by sulfuric acid treatment was used as a low-cost adsorbent for removing natural organic matter (NOM) in an artificial lake. The specific surface areas and SEM images of modified coal fly ash (MCFA) and CFA were observed. Two equilibrium models were compared to evaluate NOM removal process with a better fitting using the Freundlich model. Kinetic studies were also carried out to fit the experimental data. The pseudo second-order provided the highest coefficients of determination.

Abstract: Biomass materials are the best substitute for those made of plastic packaging materials all over the world. Widespread application of these materials can control or eliminate the increase of white pollution problem effectively. In this paper, the analysis model of biomass 450 ml lunch box was established based on Life Cycle Assessment, and then the environment Friendliness of the box, such as resource consumption, environment quality and human health, was analyzed. The results have shown that the resource consumption, environment quality and human health of biomass products were 26.6mPt, 6.23mPt, 16mPt, and these parameters of plastic products were 291mPt, 12.1mPt, 74.1mPt. Therefore, the biomass products have better environmental Friendliness than plastic products.