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Developing thermoelectric (TE) performance is impeded by the compromise of TE parameters, resulting in inadequate conversion efficiency of heat to electricity. Herein, this work reports that Mo is a particularly effective additive in Mg3Sb2‐based alloys with significantly improved electronic transport via grain‐boundary engineering and band‐structure regulation synergy. In addition, phonon transport is simultaneously suppressed by employing multiple effects, lattice imperfection scattering, reduced phonon group velocity, and enhanced atomic disorder, leading to a minimum κlat = 0.52 W m−1 K−1 at 723 K. As a result, an outstanding ZT peak of ≈1.84 at 723 K and ZTav = 1.34 within 323–723 K are achieved in Mg3Sb2‐based alloys, and the corresponding fabricated single‐leg TE module shows an exceptionally high conversion efficiency of ≈12% under a hot‐side temperature of 450 °C. These results demonstrate the great potential for advancing mid‐temperature heat harvesting in Mg3Sb2‐based materials. [ABSTRACT FROM AUTHOR]

The construction of a household integrated energy system will reduce greenhouse gas emissions and promote sustainable development. Firstly, a household energy system is proposed, which consists of a photovoltaic, wind turbine, electrolysis cell, hydrogen storage tank, and hydrogen‐fired gas turbine. The proposed system is modelled as a bi‐objective optimization problem in which the minimum daily system economic cost, and the minimum loss of energy supply probability. Secondly, a novel multi‐objective egret swarm optimization algorithm with strong search capability and fast convergence is proposed. Thirdly, a household load corresponding to a typical day in spring is chosen as the study case. The optimization results show that the daily system economic cost with the optimal number of devices is 97.48 RMB, and the loss of energy supply probability is 8.33% at the lowest. Finally, to validate the efficiency of the proposed method, the proposed method is compared with NSGA‐II (a widely used multi‐objective evolutionary algorithm). The comparison indicates that the proposed method has a better diversity due to the random searchability. As a consequence, the proposed method can be used in the optimization capacity design of the integrated energy system. [ABSTRACT FROM AUTHOR]

Wetland emergent plants are considered a good source of biochar materials, which have proven to be an effective alternative to activated carbon for water treatment and soil amendment purposes. In this work, physicochemical properties of biochar made from the root, stem, and leaf of Zizania caduciflora (ZCR, ZCS, and ZCL) under the same pyrolysis condition were compared to evaluate their ability on adsorbing cadmium (Cd) in aqueous solutions. Batch experiments exhibited that the maximum adsorption capacities of Cd(II) by different organs were in the order of ZCL (59.8 mg/g) > ZCS (40.6 mg/g) > ZCR (36.2 mg/g), which have shown some advantages in relevant scientific researches. The adsorption trends at different temperatures were determined and fitted using Langmuir and Freundlich models. The best‐fitted adsorption isotherm was found to be the Langmuir isotherm. Two different kinetic models, pseudo‐first‐order and pseudo‐second‐order, were used to fit the kinetics data, with the latter best describing the experimental data (R2 > 0.989). Statistical analyses showed that ionic strength played an important role in controlling the sorption of Cd(II) onto the ZCR, ZCS, and ZCL. Concerning the mechanism, the adsorption of cadmium on biochar is recognized to be a chemical process as surface complexation and metal ions exchange, while it also exhibits some physisorption features due to the porous and defective structure. [ABSTRACT FROM AUTHOR]

The climatic effects of aerosols derived from dimethyl sulfide (DMS) (e.g., methanesulfonic acid [MSA]) have long been of concern, particularly in the rapidly warming Arctic Ocean. Melting sea ice and increase in primary productivity can result in increased DMS emissions and MSA. However, the processes affecting MSA are complex. In addition to local sources, atmospheric chemistry processes, deposition, long‐distance transport, and regional heterogeneities influence MSA. This study used aerosol samples from the Chinese Polar Research Expedition during the summer of 2010–2016 and divided them into the Chukchi Sea (CS), high Arctic Ocean (HAO), and sea near Greenland (NG) to study the factors that influence the changes in MSA. For CS, MSA concentrations were primarily influenced by long‐distance transport from the Bering Sea air mass. Moreover, owing to the North Atlantic Oscillation, an increase in the Bering Sea temperature and a decrease in rainfall during air mass transport led to a significant increase in the concentration of MSA in the CS in 2016. When the sea ice concentration was between 0.2 and 0.6, high solar radiation likely promoted MSA formation in the HAO. For NG, the sources, rainfall and atmospheric chemical processes influenced the variations in MSA. This study highlights the importance of MSA transport in the CS and sea ice for MSA in the HAO under global warming. Plain Language Summary: The Arctic is the most sensitive region in the world to climate change. Melting sea ice and rising temperatures are affecting the ecosystems of the Arctic Ocean. Methanesulfonic acid (MSA) are generated by the oxidation of dimethyl sulfide (DMS) produced by marine phytoplankton after being released into the atmosphere. DMS‐derived aerosols in the Arctic Ocean substantially contribute to regional new particle formation and cloud condensation nuclei formation. This could have implications for climate in the Arctic Ocean. As MSA is a good indicator of DMS‐derived aerosols, comprehensively understanding how environmental changes influence MSA concentrations is crucial to clarify how emission sources and aerosol‐cloud interactions. This study demonstrates that the spatial and temporal distribution characteristics of MSA and their major influencing factors during summer in different sea areas of Arctic Ocean. The findings highlight that although the Chukchi Sea is one of the regions where the Arctic Ocean has warmed and marine primary productivity has increased significantly, the interannual variability of the MSA in this region is mainly influenced by the long‐distance transport from the Bering Sea. However, for the High Arctic Ocean regions, sea ice contributes significantly to local MSA concentrations. Key Points: The significant increase in methanesulfonic acid (MSA) in the Chukchi Sea is primarily influenced by the long‐distance transport of air masses from the Bering SeaWhen the sea ice concentration is between 0.2 and 0.6, high solar radiation may promote MSA formation in the high Arctic OceanSources, air temperature and rainfall mainly influenced the variations in MSA in the sea near Greenland [ABSTRACT FROM AUTHOR]

Global warming, increases in sea surface temperatures (SST), and reductions in sea ice may lead to changes in the distribution of global sea salt aerosol (SSA) concentrations, which may in turn affect the global climate. However, there are few global‐scale observations of SSA over marine environments. Here, we report SSA mass concentrations observed along the cruise tracks of the Chinese Polar Research Expedition in summer 2008–2018. We found the following: (1) There are significant differences between SSA concentrations in sea areas at different latitudes, and that of the Arctic Ocean was significantly lower than other sea areas; (2) over the last 10 years, the SSA concentrations in the Bering Sea were significantly higher in 2016 than in 2012, and trends from the Arctic Ocean and Southern Ocean are similar, as both showed a minimum in 2014; (3) the sea‐air temperature differences among the various marine regions studied may contribute to the different distribution of SSA concentrations; (4) sea ice fraction and SST are probably the main factors controlling the interannual changes in SSA concentrations in the Arctic Ocean and Bering Sea, respectively; and (5) The large sea‐air temperature difference in the Southern Ocean may promote the emission of SSA. Therefore, the SST parameterization of GEOS Chem model in the low SST sea area (the Southern Ocean) may have an excessively large effect on suppressing SSA emission resulting in a significant underestimation of the GEOS‐Chem model in the Southern Ocean (−62%). Key Points: Distribution patterns of sea salt aerosol mass concentrations differed significantly between sea areas at different latitudesInter‐annual changes in sea salt aerosol concentrations in different sea areas were not synchronizedGEOS‐Chem using a single sea surface temperature scale to correct the sea salt emission led to underestimation in the Southern Ocean [ABSTRACT FROM AUTHOR]

Thermoelectric cooling materials based on Bi2Te3 have a long history of unsurpassed performance near room temperature. Recently, research into price‐competitive Mg3(Bi, Sb)2‐based materials are focused on replacing traditional cooling materials. Here, the thermoelectric properties of Mg3.2Bi1.998−xSbxTe0.002Cu0.005 (x = 0.0, 0.1, 0.2, 0.3, 0.4, and 0.5) polycrystalline compounds are investigated. In all temperature regions, electrical resistivity and Seebeck coefficient are increased with Sb concentration. The electronic transport properties of Sb‐alloyed compounds are maximized by synergistically combined band engineering approaches such as band structure change caused by lattice strain, increased electronic density of states, and chemical potential shift, leading to exceptionally high‐power factor values of over 3.0 mW m−1 K−2 at room temperature. Furthermore, with increasing Sb content, thermal conductivity values are systematically reduced due to the promotion of alloy scattering of phonons and suppression of the bipolar contribution. Consequently, these multiple approaches significantly enhance thermoelectric performance, resulting in an enhancement of thermoelectric figure‐of‐merit zT above 1.1 at 348–423 K. Additionally, a zTavg of 1.1 is recorded at 300–450 K, making it an unrivaled value among the reported n‐type Mg3Bi2‐based thermoelectric materials. Overall, this work demonstrates that Mg3Bi2‐based materials are more promising for thermoelectric cooling applications compared to Bi2Te3‐based materials. [ABSTRACT FROM AUTHOR]