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This research used a two-stage fluidized-bed gasifier to investigate the effects of the temperature, equivalence ratio, and steam/biomass ratio on the syngas composition. When the operating temperature in the first stage increased from 700 °C to 900 °C, the proportion of H 2 in the syngas increased significantly. After passing through the second stage (900 °C), the syngas produced from the first stage underwent the thermal reaction again, and the proportion of H 2 was further increased. When the ER value increased from 0.2 to 0.3, the proportion of H 2 in the syngas increased; whereas, when the ER value increased to 0.4, the amount of H 2 produced was reduced. For S/B ratio, an increase to 0.5 enhanced the steam content of the gasifier and accelerated the methane–steam reforming reaction, thus producing more H 2 (up to 52 mol%). Furthermore, when the operating temperature of the fluidized bed reactor at the second stage was set at 900 °C, the proportion of H 2 in the syngas could still be effectively improved to more than 42 mol% although the operating temperature at the first stage was only 700 °C. The proportion of H 2 was enhanced to more than 52 mol% with a combination of appropriate ER and S/B ratio values. [ABSTRACT FROM AUTHOR]

Micro-honeycomb barium titanate (BaTiO 3 ) ceramics, which have uniformly distributed one-dimensional pore channels, were prepared by freeze-casting suspensions of hydrothermally synthesized BaTiO 3 nanopowder with a particle size of 100 nm. The effects of sintering schedules such as sintering temperature and holding time on pore size distribution, porosity, pore wall density and grain size were studied. The grain size on the pore wall of BaTiO 3 is around 1–2 μm after two-step sintering. The crystallographic structure of all samples was tetragonal phase regardless of the sintering schedules. Ferroelectric domains were shaped in a stripe and the domain width obviously increased after polarization. The micro-honeycomb BaTiO 3 sintered at lower temperature or shorter holding time showed larger piezoelectric coefficient d 33 and smaller dielectric constant ε r . [ABSTRACT FROM AUTHOR]

We study the BCS–Bose Einstein Condensation (BEC) crossover of a three-dimensional spin polarized Fermi gas with Rashba spin–orbital coupling (SOC). At finite temperature, the effects of non-condensed pairs due to the thermal excitation are considered based on the G 0 G pair fluctuation theory. These fluctuations generate a pseudogap even persistent above T c . Within this framework, the Sarma state or the spin polarized superfluid state and polarized pseudogap state are explored in detail. The resulting T c curves show that the enhancement of pairing due to the SOC roughly cancels out the suppression of pairing due to the population imbalance. Thus we observed that in a large portion of the parameter space, the polarized superfluid state are stabilized by the SOC. [ABSTRACT FROM AUTHOR]

A novel, mild, inexpensive, nontoxic, and effective, one-pot synthesis of vicinal diamines with benzaldehyde and aniline derivatives mediated by 10% of BiCl 3 and 3 equiv of Zn in ethanol at reflux temperature has been developed and systematically investigated. A wide range of substituted vicinal diamines compounds were obtained in good to excellent yields. The scope and limitations of this reaction have been examined. Steric and electronic effects of reactants have been discussed. [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]

A modfied polyisobutylene succinimide T154) asphaltene dispersant was prepared by modifying PIBSA with hexyl hexanol, and was applied to the preparation of FCC slurry scale inhibitor. The effects of modification temperature, modification time and material mass ratio on asphaltene dispersion and scale inhibitor on FCC slurry were investigated. The results showed that when the modification temperature was 240 °C, the modification time was 4 h,and the mass ratio of polyisobutylene succinimide m) to hexyl hexanol m) was 1u 1,the dispersion performance was better than polyisobutylene succinimide. The product had exceHent thermal stability; when the dosage of scale inhibitor was 150 g/g, the scale inhibition rate was 91.3. [ABSTRACT FROM AUTHOR]

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]

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]

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]

Cubic perovskite–type oxide Li 3/8 Sr 7/16 Hf 1/4 Ta 3/4 O 3 (LSHT) is a promising solid electrolyte material for next–generation Li–ion batteries such as all–solid–state Li batteries and Li–redox flow batteries due to its high room–temperature Li–ion conductivity and good chemical compatibility with commercial organic liquid electrolyte. High relative density is another important requirement for these applications. Here we investigate the influence of sintering additives (Li 3 BO 3 , Li 4 SiO 4 , LiF) on the density, the total Li–ion conductivity, the interfacial conductivity against commercial liquid electrolyte, and the cycling performance of the hybrid Li-ion cells. The results show that comparing with other additives, LSHT sintered with 2 wt% LiF shows the highest Li–ion conductivity (3.3 × 10 −4 S cm −1 ) and the smallest interfacial resistance (125 Ω cm 2 ) against organic electrolyte at room temperature; Li/LiFePO 4 batteries with LSHT pellets fired with 2 wt% LiF have the best cyclability and the highest coulombic efficiency (99.6 ± 0.04%) in 50 cycles. [ABSTRACT FROM AUTHOR]