Advanced Materials Research Vols. 634-638

Abstract: The cotton fabrics was treated with the blending of organic fluorine water and oil repellent finishing agent and cross-linking agent. The contact angle to water was over 120°and that to oil was above 110°after the fabrics were washed 20 times, indicating that the water and oil repellent properties and durability of fabrics were excellent. And the technology was optimized as follows: the water and oil repellent finishing agent 50g/L, cross-linking agent 4g/L, curing temperature 150°C and curing time 200s.

Abstract: The effect of polymethyl methacrylate (PMMA) was investigated for the fabrication of polyacrylonitrile (PAN) fiber. At the same time,the content of polymethyl methacrylate, the ratio of PMMA to PAN, the rheological properties of spinning dope，the mechanical properties and thermal performance of original silk were also characterized. Based on the research, when the content of PMMA is 5%, the ratio of PMMA to PAN is 7:3, it’s the suitable condition for spinning, and the original fiber have excellent properties.

Abstract: The problem of hydrogen storage is clearly connected to the necessity of development of reliable and effective methods of hydrogen compression. Efforts have been devoted to these materials to decrease their desorption temperature, enhance the kinetics and cycle life. Film for preparing hydrogen storage materials is a new method developed in recent years. The advantagesof thin film metal hydrides is obvious. For example, thin films provide large surface area, fast charging discharging rate for hydrogen. Mg films and Multilayered Mg films with rare earths, light elements and transition metals have also been studied by many researches. Preparation of Magnesium-based hydrogen storage alloy film and its hydrogen storage performance are summaried in this paper.

Abstract: A new metal-organic complex FeII2FeIII2(cbba)4(L)6 (Hcbba = 2-(4΄-chlorine-benzoyl) benzoic acid, L = 3-(2-pyridyl)pyrazole) 1 has been hydrothermally synthesized and structurally characterized by single-crystal X-ray diffraction, elemental analyses, TG and IR spectroscopy. The compound crystallizes in monoclinic, space group Cc with a = 17.729(5), b = 15.919(5), c = 33.650(5) Å, β = 92.058(5)°, V = 9491(4) Å3, C104H68Cl4Fe4N18O12, Mr = 2126.96, Dc = 1.489 g/cm3, μ(MoKα) = 0.786 mm1, F(000) = 4344, Z = 4, the final R = 0.0559 and wR = 0.1122 for 12093 observed reflections (I > 2(I)).

Abstract: Under dry argon atmosphere, the colourless and transparent ionic liquid [C₂mim][GaCl₄] was synthesized. Using [C2mim][GaCl₄] as solvent, a solution of GaCl₃ with molarity 5.227×10-3 mol/cm3 was prepared at 303.15 K and there is a equilibrum between the solute and the solvent: GaCl₃ + [C₂mim][GaCl₄] → [C₂mim][Ga₂Cl₇]. The cyclic voltammogram of the solution had been carried out relative to Al/Al³⁺ reference electrode, with GC working electrode and Ga counter electrode, with various scan rates from 30 to 700mV/s, in a temperature range of 303.15 to 343.15 K, respectively. The results indicated that (1) there were two processes: Ga(Ⅲ)→Ga(I)→Ga(0), which corresponded to the double reduction peaks in the cyclic voltammogram; (2) the first reduction process was a diffusion controlled and quasi-reversible process. Plotting current density of the peak vs the square root of scan rate, a series of straight lines were obtained, then the diffusion coefficients were obtained according to Randles-Sevcik equation in various temperature. The values of diffusion coefficient were fitted to Arrhenius equation with least-square method and value of diffusion activation energy, ED = 41.5 kJ/mol, was obtained from Arrhenius slope.

Abstract: A new coordination polymer based on cadmium nitrate and 2-（4-pyridyl-1H-benzimidazole- 5,6-dicarboxylate (H2pbd) , namely [Cd( pbd)2•(H2O)2]n•n(H2O)2, have been synthesized under hydrothermal conditions and characterized by elemental analysis, IR spectroscopy, and single crystal X-ray diffraction. The crystal of the complex crystallizes in triclinic, space group P-1 with a = 7.7200 Å, b = 8.1029Å, c = 13.0801Å, α= 96.1270(10) º, β = 102.1280(10)º, γ= 112.479(2) º, V = 723.15(12) Å3, Z =1, C28 H22 Cd N6 O12 and F(000) = 376.0. The H2pbd ligands links the Cd(II) atoms into a double stranded chain.

Abstract: The idea of non-uniform film was applied: the multilayer uniform films could be equivalent to a non-uniform film layer so that the non-uniform film system could be converted to the uniform film system and the index of refraction of each layer could be gotten by the equivalent method. The relevant design and reasonable optimization for the film system were conducted through computer so as to get a film system whose transmittance is greater than 95% with the incidence angle within 520-640 and wavelength at 420-670nm.

Abstract: A steady thermal conduction model was presented to study the temperature field and thermal stress distribution in film irradiated by continuous wave laser. The thermal effects may arise from either the absorbing inclusions or the intrinsic absorption of film. Based on the plane thermal conduction assumption, the characteristics of damage resulted from local melting or evaporation and thermal stress were discussed. The damage region resulted from local melting or evaporation smaller than that from thermal stress. The circumferential stress σ_θ is the main cause accounting for the stress damage. The normal stress perpendicular to the interface between film and substrate is the direct cause of drum type damage. The characteristics of damage in unsteady thermal conduction caused by pulse laser can be analyzed qualitatively by means of this model.

Abstract: LiFePO₄ was spinning with cellulose derivatives by electrostatic spinning for the first time. Processing conditions were adjusted to the solution concentration of 15%, an applied voltage of 25KV, the quality of mixed solvent with 4:1, and then about 0.1μm nano-fibrous non-woven fabrics can be obtained. FTIR showed that the CMCAB was synthesized successfully. Coulomb efficiency of electrode materials before and after the modification was maintained at about 100%, specific capacity of the battery in 2C of discharge rate, it was the first time that discharge specific capacity had increased from the unmodified 147.6 mAh.g^-1 to the modified 160.6 mAh.g-1^{Superscript text}. After 200 weeks' cycle, the capacity loss decreased from 11.38% to 5.11%.

Abstract: LiMn0.7Fe0.3PO4/C composite cathode material was prepared by using a solid state reaction method. The effects of annealing temperatures on the structural and electrochemical performance of LiMn0.7Fe0.3PO4/C were investigated by using X-ray diffraction (XRD), scanning electron microscope (SEM), charge–discharge tests and electrochemical impedance spectra (EIS). The results showed that all of samples have pure ordered olivine phase with orthorhombic Pnma structure. The electrochemical performance of LiMn0.7Fe0.3PO4/C can be improved remarkably with increasing temperature from 550oC to 650 oC due to increased crystallization, cation-order and decreased charge transfer resistance. However, increase temperature to 700 oC leads to bigger crystal particle size and decreased cation-order, thus higher resistance and deteriorated electrochemical properties. The sample prepared at optimized temperature of 650 oC presents a remarkable improved electrochemical performance. It delivers an initial capacity of 125.1 mAhg-1 at 0.2C, 95 mAhg-1 at 5C, and a capacity retention of 98.0% after 30 cycles.