This study evaluated the degree of conversion (DC) and polymerization shrinkage (PS) of contemporary bulk-fill resin-based composites (RBCs) including giomer materials. Two giomer bulk-fill (Beautifil Bulk Restorative [BBR], Beautifil Bulk Flowable [BBF]), two nongiomer bulk-fill (Tetric N-Ceram Bulk-fill [TNB], Smart Dentin Replacement [SDR]), and three conventional non-bulk-fill (Beautifil II [BT], Beautifil Flow Plus [BF], Tetric N-Ceram [TN]) RBCs were selected for the study. To evaluate the DC, disc-shaped specimens of 5-mm diameter and 2-mm, 4-mm, and 6-mm thickness were fabricated using customized Teflon molds. The molds were bulk filled with the various RBCs and cured for 20 seconds using a light-emitting diode curing light with an irradiance of 950 mW/cm. The DC (n=3) was determined by attenuated total reflectance Fourier transform infrared spectroscopy by computing the spectra of cured and uncured specimens. PS (n=3) was measured with the Acuvol volumetric shrinkage analyzer by calculating specimen volumes before and after light curing. The mean DC for the various materials ranged from 46.03% to 69.86%, 45.94% to 69.38%, and 30.65% to 67.85% for 2 mm, 4 mm, and 6 mm, respectively. For all depths, SDR had the highest DC. While no significant difference in DC was observed between depths of 2 mm and 4 mm for the bulk-fill RBCs, DC at 2 mm was significantly greater than 6 mm. For the conventional RBCs, DC at 2 mm was significantly higher than at 4 mm and 6 mm. Mean PS ranged from 1.48% to 4.26% for BBR and BF, respectively. The DC at 2 mm and PS of bulk-fill RBCs were lower than their conventional counterparts. At 4 mm, the DC of giomer bulk-fill RBCs was lower than that of nongiomer bulk-fill materials.

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Porous carbon with a large specific surface area, high electrical conductivity and suitable pore sizes possesses large potential for electrochemical capacitance. Herein, a 3D hierarchical porous carbon materials (PC) were synthesized through in-situ molten salt template route by using the renewable biomass waste palm shell as carbon source. The unique structures endow the synthetic PC excellent capacitive performance. As electrode for supercapacitors, the typical PC-1-700 sample showed excellent electrochemical capacitance (up to 326 F g À1 at 0.5 A g À1 ), cycling stability (99 % retention of its initial capacity) and perfect rate performance in 6 M KOH electrolyte. For security considerations, we have chosen the aqueous and the ionic liquid as the electrolyte in two-electrode cells. For the two-electrode symmetric supercapacitors, the maximum energy densities could be 10.4 Wh kg À1 in aqueous electrolytes, while it can deliver as high as 42.5 Wh kg À1 in ionic liquid electrolyte. The supercapacitor was capable of lighting a LED light bulb (3 V). The strategy holds great promise for preparing functional carbon materials from natural resources for fulfilling the demand in different areas.[a] J.

The effects of temperature on electricity performance and microbial activity were investigated in single-chamber microbial fuel cell with proton exchange membrane (S-PEM-MFC) using glucose as substrate with phosphate buffer solution(PBS). The results showed that S-PEM-MFC able to adapt to a wide temperature range of 11, 18, 25, 30 and 35°C. The open circuit voltage, polarization, power density and microbial activity of S-PEM-MFC were increased with increasing temperature from 11 to 30°C. The maximum power density were 193.8mW∙m-3 at 30°C. Compared to 30°C, the battery open circuit voltage increased by only 4.8% at 35°C, while the polarization and power density is almost the same. These results demonstrate that according to the principle of economy which 30°C should be the optimal operating temperature of S-PEM-MFC.