No abstract

Nanocomposites of blends of poly(vinylidene fluoride) (PVDF) and poly(methyl methacrylate) (PMMA) with multiwalled carbon nanotubes (CNTs) were prepared by melt mixing and hot press molding followed by quenching or annealing (120 C, 24 h). PMMA-rich nanocomposites showed higher electrical conductivity than PVDF-rich samples at identical CNT loading. At a specific composition, the quenched nanocomposites showed electrical conductivity values three to four orders of magnitude higher than those observed in annealed samples. Measurement of the dielectric constants also supported the electrical conductivity results. In the annealed samples, agglomerated CNTs located mainly in the PVDF crystalline phase were observed. Addition of CNTs promoted the crystallization, and especially, the formation of b-crystals, which was confirmed by X-ray diffraction. The thermal behavior of nanocomposites from differential scanning calorimetry (DSC) analysis was explained in terms of the three-phase model involving the presence of the rigid amorphous fraction, the mobile amorphous fraction, and the crystalline phase. POLYM. COMPOS., 36:1195-1204

This study investigates the improvement of the CO 2 sequestration percentage of a ground granulated blast furnace slag (GGBF-slag) with surface modification using a NaOH solution. The amount of CO 2 sequestration of the GGBF slag increased via the surface modification with the NaOH solution in the direct carbonation method. The increase of the carbonation percentage of the GGBF slag resulted from the increase in the hydraulic activity of the GGBF-slag. The carbonation percentage on the basis of the total calcium oxide of the GGBF slag was approximately 10 times larger than that of the GGBF-slag without the surface-modification. The carbonation rate depended on the morphology of the calcium carbonates formed on the surface of the GGBF-slag.

In this research, in order to develop technology/country-specific emission factors of methane (CH4) and nitrous oxide (N2O), a total of 585 samples from eight gas-fired turbine combined cycle (GTCC) power plants were measured and analyzed. The research found that the emission factor for CH4 stood at “0.82 kg/TJ”, which was an 18 % lower than the emission factor for liquefied natural gas (LNG) GTCC “1 kg/TJ” presented by Intergovernmental Panel on Climate Change (IPCC). The result was 8 % up when compared with the emission factor of Japan which stands at “0.75 kg/TJ”. The emission factor for N2O was “0.65 kg/TJ”, which is significantly lower than “3 kg/TJ” of the emission factor for LNG GTCC presented by IPCC, but over six times higher than the default N2O emission factor of LNG. The evaluation of uncertainty was conducted based on the estimated non-CO2 emission factors, and the ranges of uncertainty for CH4 and N2O were between −12.96 and +13.89 %, and −11.43 and +12.86 %, respectively, which is significantly lower than uncertainties presented by IPCC. These differences proved that non-CO2 emissions can change depending on combustion technologies; therefore, it is vital to establish country/technology-specific emission factors.

No abstract