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The garnet-type solid Li-ion conductor, Li6.4La3Zr1.4Ta0.6O12, is viewed as a promising solid-state electrolyte for the next-generation high-performance Li-ion battery because of its high ionic conductivity and stability. The previous researches, in order to avoid Li volatilization loss during solid-state reaction of sintering, mother powder with the same composition as green bodies was usually used to cover the samples, it would waste the expensive raw materials and increase the fabrication cost. In this study, a new method was proposed to prepare the Li6.4La3Zr1.4Ta0.6O12 ceramic solid-state electrolyte where the Li loss is compensated by the outside Li2CO3. Samples prepared by this method have pure garnet phase and compact micromorphology with few pores. These samples have a high Li-ion conductivity of 2.9×10−4 S/cm and a low activation energy of 0.37 eV at room temperature. The electronic conductivity is 1.08×10−8 S/cm, which can be neglected for solid-state electrolyte. [ABSTRACT FROM AUTHOR]

Pure anorthite porous ceramics have been fabricated using γ-Al2O3, CaCO3, and SiO2 as raw materials through foam-gelcasting method. XRD, thermal analysis, SEM, and TEM were used to study the synthesis and grain growth of anorthite during the in situ process. The results indicated that the initiator (ammonium presulfate) took part in the chemical reaction to form CaSO4, which played an effective role during synthesis of anorthite. Besides, CaO and CaSiO2 were the other intermediate phase during synthesis. Anorthite first occurred at 1050°C, and it was the only phase after it sintered over 1260°C. With sintering temperature increasing from 1300°C to 1450°C, the large sphere pore wall got denser and the anorthite grains obviously showed platelike. It was deduced that the preferential growth of anorthite crystals was parallel to the (004) plane. [ABSTRACT FROM AUTHOR]

Porous YSZ ceramics were prepared by a gel-casting method using tert-butyl alcohol (TBA) as solvent and Al2O3 fiber as reinforcement. Effects of sintering temperature, soaking time and Al2O3 fiber content on porosity, microstructure, compressive strength, and fracture toughness of the porous ceramics were studied. Compressive strength of porous YSZ ceramics was improved while the porosity decreased with the increase of sintering temperature and soaking time. Addition of Al2O3 fibers significantly strengthened and toughened porous YSZ ceramics; however, the laws of strengthening and toughening were different. The strength of the porous YSZ ceramics reached maximum at the addition of 10vol% Al2O3 fibers, and the corresponding compressive strength and flexural strength were 100.2±25.4MPa and 61.5±11.3MPa, respectively. Fracture toughness of the porous YSZ ceramics monotonically increased with increasing of Al2O3 fibers, and could be improved from 0.5MPam1/2 to 1.2MPam1/2 (improved by 140%). The strengthening and toughening mechanisms of Al2O3 fibers were discussed. [ABSTRACT FROM AUTHOR]

Abstract: In order to explore and improve the applicability of FireFOAM which is a new fire modeling code on the numerical simulation of spread simulation over the solid surface, the single-wall corrugated board is selected to evaluate the influence on the flame spread with different board width, heat release rate of fire source and the board located angle. Six cases are used and the simulation results can reflect the change trend of probe temperate and the flame spread rate with the three variables, generally aligning with the rules from previous experiments. Moreover, further studies are needed to evaluate and improve the current FireFOAM code further. [Copyright &y& Elsevier]

Abstract: The multi-component fuel based eddy dissipation concept(EDC) model, PaSR based soot model and grey gas based FvDOM radiation model etc in ExfireFoam is further extended to simulate a 30cm × 30cm ethanol-gasoline square pool fire. The predictions achieved good agreement with the measurements for flame height and the radial temperature profiles at different heights, demonstrating the good potential of the ExfireFoam for predicting the combustion process of pool fires from multi-component fuels. [Copyright &y& Elsevier]

This study shows that C can degrade pBR322 plasmid DNA at room temperature without photoactivation. The degradation was enhanced by increasing incubation temperature, reaction time or C concentration. We also found that superoxide radical anions (O) were formed in the C solution. Superoxide dismutase significantly inhibited DNA cleavage and O generation induced by C. These results suggest that DNA cleavage was caused by the formation of reactive oxygen species induced by C at room temperature. Furthermore, we demonstrate that the DNA degradation was significantly inhibited by acid amide chemicals such as formamide, and by increased ionic strength of the reaction solution. These results indicate that the DNA conformation stability and the surface properties of C are important factors regulating DNA degradation. We propose that C can bind DNA, decrease DNA conformation stability, and induce the formation of reactive oxygen species and DNA cleavage at room temperature. Our results provide a possible explanation for the genotoxicity of C, which should be considered in future use of this particular nano-material. [ABSTRACT FROM AUTHOR]

Abstract: Porous yttria-stabilized zirconia (YSZ) ceramics were fabricated by tert-butyl alcohol (TBA)-based gel-casting method for potential applications in heat-insulation materials. The effect of sintering temperature on compressive strength of porous YSZ ceramics was investigated on the basis of measurements linear shrinkage, porosity and pore size. As the sintering temperature increased from 1350 to 1550°C, a decrease of porosity from 77 to 65%, a decrease of average pore size from and an increase of linear shrinkage from 15.4 to 31.8% were observed. The compressive strength increased remarkably from 3 to 27MPa with increasing sintering temperature from 1350 to 1550°C, which was related to the corresponding change of linear shrinkage, porosity, pore size and microstructure. A remarkable decrease of compressive strength with increasing porosity was observed. The compressive strength decreased also with increasing pore size. [Copyright &y& Elsevier]

Abstract: Silver nanoparticles and nanoplates were prepared at the air/AgNO3 aqueous solution interfaces under poly(9-vinylcarbazole) (PVK) monolayers when illuminated by UV-light at room temperature and elevated temperatures, respectively. When the illuminated films at the air/water interfaces were covered by carbon-coated copper grids, nanoplates were formed even at room temperature, and the size of the nanoplates was much larger than those formed at the air/water interface under the same experimental conditions, indicating that copper took part in the formation of Ag nanoplates through the galvanic displacement reaction between Cu and Ag+ ions with the help of carbon layer to conduct electrons. It was found that the basal plane of these nanoplates is the (111) face of a face-centered cubic (fcc) Ag crystal. Although platelike structure can be formed at the carbon-coated copper grid/AgNO3 aqueous solution interface without PVK film, it shows different features from those with PVK films, indicating that PVK film plays an important role in the formation of regular large nanoplates. Further observations indicate that special restrained microenvironment, adsorption of PVK molecules on a specific crystal face, anisotropic growth and attachment of the nanoparticles are responsible for the formation of the nanoplates. [Copyright &y& Elsevier]

Abstract: The garnet-related oxide with nominal formula Li7La3Zr2O12 prepared by the sol–gel method is cubic, space group Ia-3d with lattice parameter a =12.9720Å at room temperature. The occupancies of three lithium positions (24d, 48g, 96h) and the position of a small amount of Al3+ (ca 0.61wt%) inside the grains were determined by neutron diffraction. The occupancy of the 24d Li sites was reduced to 36.0% by the Al3+ occupying the 48g sites. The bulk and total Li+-ion conductivity at 25°C was 3.1×10−4 Scm−1 and 1.4×10−4 Scm−1 with an activation energy 0.34eV in the temperature range 25–160°C. [Copyright &y& Elsevier]

Boron carbide submicron powder was synthesized with boron oxide and graphene as starting materials by gas-solid reaction method using two different apparatuses. The effects of calcination temperature and holding time, apparatus type and B 2 O 3 /C ratio of the starting materials on the phase composition and morphology of the synthesized powders were evaluated. A newly formed residual carbon morphology distinct from original graphene were present in samples synthesized at a higher B 2 O 3 /C ratio or temperature. The synthesis temperature of ∼1500 °C was found to be more suitable to obtain boron carbide powder without the existence of residual carbon. The new type of apparatus enabled the synthesis of boron carbide phase at a relatively lower temperature, due to its more efficient use of B 2 O 3 vapor. [ABSTRACT FROM AUTHOR]

The NASICON oxides with general formula Li1+x Y x Zr2−x (PO4)3 (0.1 ≤ x ≤ 0.2) are prepared by conventional solid-state reaction. The samples are characterized by XRD, SEM, electrochemical impedance spectroscopy and 7Li MAS NMR measurements. The structures are refined by the Rietveld method from powder X-ray diffraction data. With the introduction of Y3+, the volume of the large M1 cavity is reduced and the rhombohedral NASICON phase is stabilized at room temperature. The bulk and total Li+ conductivities of Li1.15Y0.15Zr1.85(PO4)3 sintered by SPS are 1.4 × 10−4 and 0.71 × 10−4 S cm−1 at 25 °C, respectively; the activation energy is about 0.39 eV in the temperature range 300–473 K. [ABSTRACT FROM AUTHOR]

Abstract: The activity coefficients at infinite dilution, , for both polar and non-polar solutes in the ionic liquid 1-ethyl-3-methylimidazolium tetracyanoborate [EMIM][TCB] have been determined by gas–liquid chromatography at the temperatures from (303 to 343)K. The partial molar excess enthalpies at infinite dilution of the solutes in the ionic liquid were also calculated from the temperature dependence of the values. The selectivity for the hexane/benzene and cyclohexane/benzene separation problems was calculated from experimental infinite dilution activity coefficient values and compared to the other ionic liquids, taken from the recent literature. [Copyright &y& Elsevier]