Advanced Materials Research Vols. 912-914

Abstract: The quality of waterproof and cohesive layer determines the service life of bridge deck pavement. Conventional modified bitumen bonding layer exits some deficiencies that its shear strength is low, construction process is complexity and it need to spread gravel. In order to solve the problem, the new type of waterproof and cohesive layer called PCMA is developed and researched. Through the indoor test study on road performance of the PCMA, the results shows that PCMAs shear strength, drawing stress and fatigue life are significantly higher than other waterproof and cohesive layer. It is especially suitable for hot and humid regions.

Abstract: KH₂PO₄-WO₃/γ-Al₂O₃ solid acid catalyst was prepared by the method of impregnation. According to the lactic acid dehydration production of acrylic acid reaction, some parameters including the load of WO₃ on γ-Al₂O₃, the calcination temperature, the reaction temperature and lactic acid concentration were investigated. The results show that the conversion of lactic acid was 92%, and the selectivity of acrylic acid was 29% under the optimized preparation conditions.

Abstract: Ni_0.8Co_0.1Mn_0.1(OH)₂ precursors prepared by co-precipitation method were served to synthesize LiNi_0.8Co_0.1Mn_0.10₂ cathode materials by sintering with LiOH·H₂O at high temperature. It is shown from XRD analysis and electrochemical measurements that these precursors synthesized at different aging time are all composed of two phases, α-Ni (OH)₂ and β-Ni (OH)₂.With aging process lasting longer,relatively content of α-Ni (OH)₂ in precursors increase , peak intensity ratios of I₍₀₀₃₎/I₍₁₀₄₎ in LiNi_0.8Co_0.1Mn_0.10₂ get larger, the more complete of layer structure, the lower of Li⁺/Ni²⁺cation mixing. Results indicate that the existence and content increase of α-Ni (OH)₂ phase with aging process lasting can inhibit the cation mixing efficaciously. LiNi_0.8Co_0.1Mn_0.10₂ obtained from precursor aged 12h has a good cyclic performance, capacity retention rate reaches 92.8% after 30 cycles.

Abstract: Stone Matrix Asphalt (SMA) is a gap-graded mix that is gaining popularity worldwide. Various types of fibers are used as additions in SMA asphalt mixture. However, there is not sufficient information available for the selection of different fibers with regard to different applications of SMA pavement. In this paper, SMA-13 using three different fibers: lignin fiber, polyester fiber and basalt mineral fiber, is used as an example. Based on the Marshall test, Schellenberg Binder Drainage test, Cantabro test, Residential stability test, Freezethaw cycle test, Rutting test and Bending test of small beam of the mixtures, the influences of different fibers on road performance of SMA mixture were investigated. The results show that SMA-13 mixtures using mineral fibers exhibit optimal high temperature and low temperature stability; while SMA mixtures using lignin fibers exhibit optimal water stability.

Abstract: The influence of heat treatment parameters, i.e. solution temperature, solution time, aging temperature and aging treatment on the mechanical properties and crashworthiness of crash boxes produced with 6101 aluminum alloy were studied. The optimal heat treatment processing was obtained as follows: 510°C×45min+175°C×7h. The crash boxes were treated under different heat treatments, i.e. T1 temper,T4 temper and T6 temper and then compressed under static pressure. The results indicate that the energy absorption of crash box can after T6 treatment is significantly higher than the samples under T1temper and T4 temper, which have similar energy absorption. The peak force of static pressure crash boxes treated under T6 temper is obviously higher than the other two tempers.

Abstract: The influence of heat-treatment on mechanical properties and wear resistance of ultra-high Mn steel was studied, micro-structure and fracture surface were analyzed by optical microscope (OM) and selected electron microscope (SEM). According to the results, optimized heat-treatment makes improvement in mechanical properties, and dispersed tiny carbides precipitate on Austenite matrix instead of grain boundary contributes to the excellent mechanical properties and wear resistance.

Abstract: LiMn₂O₄ and LiNi_0.5-xCr_2xMn_1.5-xO₄(x=0, 0.05) cathode materials of spinel structure were prepared via co-precipitation derived precursors and subsequent high-temperature sintering between the precursors and LiOH. XRD, SEM and electrochemical tests were performed for the characterization of the as-prepared samples. The results show that the substitutions of Ni and Cr for Mn can not prevent Mn²⁺from being oxidized into Mn³⁺ in solution process, yet do not change their final crystal structures of spinel with or without substitution, and after substitution the first charge and discharge capacities decrease but its cyclic capability is improved significantly, especially for the Ni and Cr co-substitution

Abstract: GaN films were deposited on metal Ni substrates using electron cyclotron resonance plasma-enhanced metal organic chemical vapour deposition system (ECR-PEMOCVD). The nitridation time dependent structural and morphological characteristics of GaN films were systematically investigated by reflection high energy electron diffraction (RHEED), X-ray diffraction (XRD), and scanning electron microscope (SEM) analysis. The results indicate that it is feasible to deposit GaN films on Ni metal substrate under the proper deposition procedures. The high quality GaN films with c-axis preferred orientation and dense and uniform microstructure are successfully obtained under the optimized nitridation time. The GaN/Ni structure has great potential for the improvement of short-wavelength optical devices with excellent heat dissipation.

Abstract: The study was designed to observethe protective effect of taurine(Tau) against doxorubicin-induced cardiotoxicity in rats.Doxorubicin were administered at the dosage of 2.5 mg·kg^-1 oncea week, ip for a period of 4 consecutive weeks. Taurine were administered atthe dosages of400,200and 100 mg·kg^-1·d^-1, poby gavage for 30 consecutive days. Taurine at the doses of 400 and 200 mg·kg^-1significantly reduced CK-MB, GOT and LDH and increased SOD levelsin the doxorubicin-treated animals. Thus, taurine ameliorated doxorubicin-induced cardiotoxicity by reducingoxidative stress, abnormal cellular morphology in rat. The study show the protective effect oftaurine against doxorubicin-induced cardiotoxicity.

Abstract: In this article, classification methods using mathematical morphology are used to generate the internal and external contours of an image of a natural fiber, "Rhektophyllum camerunense" taken by an epifluorescent electron microscope. The presence of impulse noise in the captured image and the presence of an almost identical texture characterized by the heterogeneity of the basic cells whose microstructure composes the fiber, make it difficult to use conventional methods of image analysis. As the fiber of R. camerunense consists of basic cells interconnected by cellulosic hemicellulose, their delineation is possible by detecting the contour of the lumens. To distinguish the regions of basic cells, binarization is performed after application of a 3 × 3 median filter. The results obtained allow development of a method for calculating the geometrical parameters of the cross section of the fiber R. camerunense and generation of the basic structure of the cross section by Voronoi diagram.