We created unique interconnected partially graphitic carbon nanosheets (10-30 nm in thickness) with high specific surface area (up to 2287 m(2) g(-1)), significant volume fraction of mesoporosity (up to 58%), and good electrical conductivity (211-226 S m(-1)) from hemp bast fiber. The nanosheets are ideally suited for low (down to 0 °C) through high (100 °C) temperature ionic-liquid-based supercapacitor applications: At 0 °C and a current density of 10 A g(-1), the electrode maintains a remarkable capacitance of 106 F g(-1). At 20, 60, and 100 °C and an extreme current density of 100 A g(-1), there is excellent capacitance retention (72-92%) with the specific capacitances being 113, 144, and 142 F g(-1), respectively. These characteristics favorably place the materials on a Ragone chart providing among the best power-energy characteristics (on an active mass normalized basis) ever reported for an electrochemical capacitor: At a very high power density of 20 kW kg(-1) and 20, 60, and 100 °C, the energy densities are 19, 34, and 40 Wh kg(-1), respectively. Moreover the assembled supercapacitor device yields a maximum energy density of 12 Wh kg(-1), which is higher than that of commercially available supercapacitors. By taking advantage of the complex multilayered structure of a hemp bast fiber precursor, such exquisite carbons were able to be achieved by simple hydrothermal carbonization combined with activation. This novel precursor-synthesis route presents a great potential for facile large-scale production of high-performance carbons for a variety of diverse applications including energy storage.
This study was conducted to evaluate the application of carbon isotope discrimination (CID) as a selection criterion for improving water use efficiency (WUE) and productivity of barley (Hordeum vulgare L.) under field and droughtstress conditions in a greenhouse. A total of 54 genotypes were screened for variability in CID under field conditions, while 23 genotypes were evaluated under water-deficit conditions in the greenhouse. A survey of leaf CID of 54 genotypes at two field locations showed more than 2.14& difference between extreme genotypes. Significant (P £ 0.05) genotypic variation was found in WUE and CID that had a negative strong correlation. There was a negative correlation between leaf CID and aerial biomass in the greenhouse and among six-row genotypes in the field. Correlations between leaf CID across field locations and across irrigation regimes in the greenhouse were significant (experiment 1, r = 0.79 and 0.94 for six-and two-row genotypes), suggesting stability of the CID trait across different environments. Overall, these results indicate the potential of leaf CID as a reliable method for selecting for high WUE and productivity in barley breeding programmes in the Canadian prairies. Further work is currently underway to determine heritability ⁄ genetics of leaf CID and application of molecular marker-assisted selection for the traits in barley breeding programmes.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.