No abstract

No abstract

Global marine fisheries are currently underperforming, largely due to overfishing. An analysis of global databases finds that resource rent net of subsidies from rebuilt world fisheries could increase from the current negative US$13 billion to positive US$54 billion per year, resulting in a net gain of US$600 to US$1,400 billion in present value over fifty years after rebuilding. To realize this gain, governments need to implement a rebuilding program at a cost of about US$203 (US$130–US$292) billion in present value. We estimate that it would take just 12 years after rebuilding begins for the benefits to surpass the cost. Even without accounting for the potential boost to recreational fisheries, and ignoring ancillary and non-market values that would likely increase, the potential benefits of rebuilding global fisheries far outweigh the costs.

In this study, Bi was selected to dope PbTe nanocubes to develop high performance n-type PbTebased thermoelectric materials via nanostructure engineering using a facile solvothermal method. Bi dopants effectively improve the electrical transport properties of the as-sintered PbTe nanomaterials by tuning the carrier concentrations, achieving promising electrical conductivity and Seebeck coefficient which are comparable to bulk materials. Moreover, a low lattice thermal conductivity has been secured in the sintered Bi-doped PbTe nanomaterials, which is remarkably lower than its bulk counterparts. Extensive experimental and theoretical evidences reveal that such low lattice thermal conductivity is attributed to the enhanced phonon scattering by the high density of grain boundaries and dislocations, in turn, leading to an enhanced peak ZT ~1.35 at 675 K for n-type Pb 0.99 Bi 0.01 Te.

Chemistry-related software, or chemistry “apps”, on hand-held and portable touch-controlled computers such as smartphones and iPods are seeing dramatic growth with increasing adoption rates. This review covers about 30 popular and mostly free apps that can be used to learn chemistry and to serve as reference or research tools. The target audience includes students in high school, college, and graduate school, chemical professionals, and teachers.