The voltage of carbon-based aqueous supercapacitors is limited by the water splitting reaction occurring in one electrode, generally resulting in the promising but unused potential range of the other electrode. Exploiting this unused potential range provides the possibility for further boosting their energy density. An efficient surface charge control strategy was developed to remarkably enhance the energy density of multiscale porous carbon (MSPC) based aqueous symmetric supercapacitors (SSCs) by controllably tuning the operating potential range of MSPC electrodes. The operating voltage of the SSCs with neutral electrolyte was significantly expanded from 1.4 V to 1.8 V after simple adjustment, enabling the energy density of the optimized SSCs reached twice as much as the original. Such a facile strategy was also demonstrated for the aqueous SSCs with acidic and alkaline electrolytes, and is believed to bring insight in the design of aqueous supercapacitors.

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The poor intrinsic conductivity of MoS2 presents a huge barrier for the exploitation of its versatile properties, especially as an electrochemical capacitor (EC) electrode and hydrogen evolution reaction (HER) catalyst. Toward this challenge, TiN nanorods coated by randomly oriented MoS2 nanosheets (TMSs) are engineered as state-of-the-art electrodes for ECs and HER. In light of the synergistic effects, TMS electrodes show favorable performance as both a binder-free EC electrode and HER catalyst. Importantly, the optimal TMS achieves an areal capacitance of 662.2 mF cm–2 at 1 mA cm–2 with superior rate capability and ultralong cycling stability. As the catalyst for HER in 0.5 M H2SO4, it shows an overpotential of 146 mV at 10 mA cm–2, a favorable Tafel slope, and good electrocatalytic stability. All of the results highlight the favorable integration of TiN and MoS2 and provide clear insight correlating the hybrid structure and the corresponding electrochemical performance.

Data have been collected and physical and statistical models have been constructed to estimate unknown occupational radiation doses among 90,000 members of the U.S. Radiologic Technologists cohort who responded to a baseline questionnaire during the mid-1980s. Since the availability of radiation dose data differed by calendar period, different models were developed and applied for years worked before 1960, 1960- 1976 and 1977-1984. The dose estimation used available film-badge measurements (approximately 350,000) for individual cohort members, information provided by the technologists on their work history and protection practices, and measurement and other data derived from the literature. The dosimetry model estimates annual and cumulative occupational badge doses (personal dose equivalent) for each technologist for each year worked from 1916 through 1984 as well as absorbed doses to organs and tissues including bone marrow, female breast, thyroid, ovary, testes, lung and skin. Assumptions have been made about critical variables including average energy of X rays, use of protective aprons, position of film badges, and minimum detectable doses. Uncertainty of badge and organ doses was characterized for each year of each technologist's working career. Monte Carlo methods were used to generate estimates of cumulative organ doses for preliminary cancer risk analyses. The models and predictions presented here, while continuing to be modified and improved, represent one of the most comprehensive dose reconstructions undertaken to date for a large cohort of medical radiation workers.

Three-dimensional honeycomb-like hierarchical structured carbon was synthesized from high-ash-content sewage sludge and exhibited remarkable specific capacitance and excellent long-term cycling stability for high-performance supercapacitors.In this work we demonstrate that three--dimensional honeycomb--like hierarchical structured carbon (HSC) can be prepared by using high--ash--content sewage sludge as carbon precursor for the first time. The fly--silicon process acts a crucial role in the formation of honeycomb--like hierachical structures. The as--resulted HSC exhibits novel honeycomb--like framework, high specific surface area (2839 m 2 g --1 ), large pore volume (2.65 cm 3 g --1 ), interconnected hierarchical porosity, and excellent electrochemical performance. The high specific capacitance of 379 F g --1 as well as excellent rate capability and outstanding cycling stability (over 90% capacitance retention after 20,000 cycles even at a high current density of 20 A g --1 ), makes it suitable for high--performance supercapacitor electrode materials. The assembled HSC//HSC symmetric supercapacitor presents an enhanced supercapacitive behavior with high energy density of 30.5 Wh kg --1 in aqueous solution. The strategy provides an effective method to achieve high--performance electrode materials derived from other high--ash--content biomass wastes for supercapacitors.