Advanced Materials Research Vols. 798-799

Abstract: The SENKIN subroutine package of CHEMKIN chemical kinetics package was used to analyze the gas explosion at three initial temperatures of 1000K, 1050K and 1100K in restricted space, based on the detailed chemical kinetics mechanism of methane combustion. The changes of explosion temperature, explosion pressure and free radicals O, H and OH generated were discussed. The results show that with elevated initial temperature, the explosion temperature increases, while the explosion pressure decreases, and the ignition delay time is shortened. Moreover, the higher the initial temperature is, the higher the mole fraction of free radicals is.

Abstract: Freestanding ultralong (900 μm) aligned carbon nanotube (ACNT) films were studied as both an electrode material and a dry adhesive binder with the current collector in lithium ion batteries. Results revealed the formation of a solid electrolyte interface (SEI). The amazingly large initial discharge capacity (1836 mAh g^-1) indicated that the ACNT electrode we utilized had great potential for the intercalation of Li ions resulted from extremely large surface area of ACNT films. And electrochemical performances also exhibited excellent cycling stability for this ACNT electrode because of the presence of SEI and the unique structure of the electrode itself.

Abstract: With the aim of invesgating effect of the two polymer phases of ABS on improved fire performance of ABS filled with magnesium hydroxide, we have prepared ABS filled with surface-treated magnesium hydroxide (MH) via compounding poly (styrene-acrylonitrile) (SAN) and polybutadiene filled with MH as well as by compounding ABS and MH. These ABS filled with MH were compared with unfilled ABS by investigating their fire performance and thermal degradation with LOI test, UL-94 test, DSC and FTIR. The dehydration of MH did not effectively increase fire performance and thermal stability of ABS filled with 60.0wt% MH when MH resided in SAN of ABS due to compounding of ABS and MH. The dehydration of MH was clearly able to change the decomposition behavior of the two polymer phases of ABS in ABS filled with 60.0wt% MH when MH resided in the polybutadiene of ABS, resulting in an efficient enhancement of fire performance.

Abstract: A theoretical study on Ru_1-xPd_xZr solid solutions has been carried out by means of periodic density functional theory (DFT) at generalized gradient approximation (GGA) level. Stability and martensite transformation analysis were performed based on the formation energy and electronic structures. The results show that the ternary phase Ru₂Pd₆Zr₈ is stable because the de-mixing energy of Ru₂Pd₆Zr₈ is-0.05eV. The calculated cohesive energy, bond length and density of states showed that the orthorhombic-Ru₂Pd₆Zr₈ is more stable than bcc-Ru₂Pd₆Zr₈, for the martensite transformation occurs when about 70% of the Ru atoms are replaced by Pd atoms. The studies provide a theoretical basis to the development and application of Ru_1-xPd_xZr solid solution.

Abstract: A new soil water characteristic curve (SWCC) model considering urea concentration is presented in the paper. Two assumptions are used to obtain the model. One is SWCC which could be described by exponential functions in the experiments. Another is relationship between the parameters of exponential functions and urea concentration which is linear based on experimental data. In the research, we have carried out some experiments of SWCC and obtained some valuable data which could affect urea concentration. By using linear fitting, an exponential function between water content and suction and urea concentration is established.

Abstract: Abstract. The article established electrospun nanofibers as extraction medium to enrich and purify salidroside and detected the content changes by high performance liquid chromatography. 4 g polystyrene was dissolved in 20 mL butanone for spinning. The electrospun nanofibers was processed and loaded into solid extraction column. 3 mL sample was injected and eluted by 10 mL methanol at the speed of 2 mL/min, collecting the elution for the HPLC analysis. The results show that the relative content of solidroside increased from 24% to 55% and the extraction recovery was above 92%. The method is simple and convenient. It can replace traditional solid phase extraction to enrich solidroside.

Abstract: A new series of hydrophobic-hydrophilic multiblock copolymers derived from fluorine terminated poly (arylene ether ketone) as hydrophobic blocks and phenoxide terminated sulfonated poly (arylene ether sulfone) as hydrophilic blocks were successfully synthesized and evaluated for use as proton exchange membranes (PEMs). All the hydrophobic and hydrophilic oligomers were synthesized via molecular-weight controlled step growth polymerization of the monomers. ¹H NMR spectra were used as characterization tool to determine the telechelic oligomers molecular weight and multiblock copolymers structure. The morphologies of multiblock copolymers were investigated by transmission electron microscopy (TEM), which showed they had a clear microphase-separated structure between the hydrophilic domains and hydrophobic domains. All the sulfonated poly (arylene ether sulfone)-b-poly (arylene ether ketone) copolymers can easily be cast into tough membranes for applications in proton exchange membrane.

Abstract: In this paper, the high temperature was adopted to treat the composited photocatalysts. The effects of different heat treatment temperature, rare-earth and concentration rare-earth on photocatalytic activity were investigated. The results showed that the photocatalytic activity was better when potassium titanate whiskers were calcinated at 600 0C without rare-earth doping. The effect of potassium titanate whiskers doped neodymium ion was the best, the degradation rate could increase to 59.0%. When neodymium nitrate was 0.04g, the degradation rate of composites photocatalysts was the best. The photodegradation rate could reach 74.02%. And the degradation rate of 10 mg/L tetracycline at 20 0C could increase to 86.31%.

Abstract: The reaction kinetics of the dehydrogenation of isobutane over V-K-O /ZSM5 catalyst was investigated. The powerfunction model was established;The isobutane dehydrogenation reaction tests were carried out between 833-863K and reaction pressure to atmospheric pressure by changing the contact time(w/F=0.464-0.532gh/mol) ,through the experimental data the kinetics of model parameters were analyzed.The results show that the power-function kinetic model is reasonable,the apparent activation energy is 177.7492KJ/mol.

Abstract: To study water stability of Sasobit warm mix drainage asphalt (WMDA) and improve it, OGFC-13 WMA is primarily prepared with polyester fibre and Sasobit. According to the test results of specimens, formed at 5 different compaction temperatures by marshall tests, the optimal compaction temperature is determined. Then, general water stability tests were used to test the water stability performance of 4 kinds of asphalt mixtures, which were porous asphalt mixture of hot mix (OGFC-1),Sasobit WMDA without any anti-stripping agents (OGFC-2), Sasobit WMDA added hydrate lime (OGFC-3) and Sasobit WMDA added hydrated lime with quick lime (OGFC-4).Test results show that optimal compaction temperature is 150°C; water stability order (OGFC-3>OGFC-1>OGFC-2>OGFC-4) shows that using hydrated lime has beneficial yet limited effects to it. Hydrated lime with quick lime should be avoided for its adverse effect.1.5% hydrated lime shows best water stability.