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Global aquaculture makes an important contribution to food security directly (by increasing food availability and accessibility) and indirectly (as a driver of economic development). in order to enable sustainable expansion of aquaculture, we need to understand aquaculture's contribution to global greenhouse gas (GHG) emissions and how it can be mitigated. This study quantifies the global GHG emissions from aquaculture (excluding the farming of aquatic plants), with a focus on using modern, commercial feed formulations for the main species groups and geographic regions. Here we show that global aquaculture accounted for approximately 0.49% of anthropogenic GHG emissions in 2017, which is similar in magnitude to the emissions from sheep production. The modest emissions reflect the low emissions intensity of aquaculture, compared to terrestrial livestock (in particular cattle, sheep and goats), which is due largely to the absence of enteric cH 4 in aquaculture, combined with the high fertility and low feed conversion ratios of finfish and shellfish.

We report a method to fabricate carbon nanotube reinforced Nylon filaments through an extrusion process. In this process, Nylon 6 and multiwalled carbon nanotubes (MWCNT) are first dry mixed and then extruded in the form of continuous filaments by a single screw extrusion method. Thermo gravimetric analysis (TGA) and differential scanning calorimetry (DSC) studies have indicated that there is a moderate increase in Tg without a discernible shift in the melting endotherm. Tensile tests on single filaments have demonstrated that Young’s modulus and strength of the nanophased filaments have increased by 220% and 164%, respectively with the addition of only 1wt.% MWCNTs. SEM studies and micromechanics based calculations have shown that the alignment of MWCNTs in the filaments, and high interfacial shear strength between the matrix and the nanotube reinforcement was responsible for such a dramatic improvement in properties.

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Using a PVT apparatus for high pressure and temperature combined with a magnetic suspension balance, the solubility of carbon dioxide in linear and branched polypropylene (PP) was measured at temperatures from (453 to 493) K and at pressures of up to 31 MPa. The solubility of CO2 in both molten polymers increased linearly with pressure and decreased with temperature. However, above 20 MPa, the solubility−pressure relationship was no longer linear. This might be due to a significant hydrostatic effect on the swelling of the polymer that results from gas absorption above 20 MPa, so that swelling is no longer linearly related to pressure. At a high pressure, swelling significantly affects solubility, which is then no longer linearly related to pressure. It was noted that linear PP absorbs more gas than branched PP, due to the branched PP’s chain entanglement. The solubility of CO2 in the PP melts was compared with semiempirical data (determined by empirically measuring gas uptake and theoretically predicting swelling) and theoretical values calculated from the Simha−Somcynsky (SS) and Sanchez−Lacombe (SL) equations of state (EOSs). The Simha−Somcynsky equation of state (SS-EOS) was observed to have a better prediction capacity of the swelling effect and to thus provide better solubility predictions for both semiempirical and theoretical cases than the Sanchez−Lacombe equation of state (SL-EOS).