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For layered oxide cathodes, aluminum doping has widely been shown to improve performance, particularly at high degrees of delithiation. While this has led to increased interest in Al-doped systems, including $\mathrm{LiNi_{0.8}Co_{0.15}Al_{0.05}O_{2}}$ (NCA), the aluminum surface environment has not been thoroughly investigated. Using hard x-ray photoelectron spectroscopy measurements of the Al 1s core region for NCA electrodes, we examined the evolution of the surface aluminum environment under electrochemical and thermal stress. By correlating the aluminum environment to transition metal reduction and electrolyte decomposition, we provide further insight into the cathode-electrolyte interface layer. A remarkable finding is that Al-O coatings in LiPF$_6$ electrolyte mimic the evolution observed for the aluminum surface environment in doped layered oxides. ECS transactions 80(10), 197 - 206 (2017). doi:10.1149/08010.0197ecst Published by Pennington, NJ

Synopsis The biological structures that fill the environment around us are derived from materials produced by organisms. These biological materials are key to the mechanical function of organisms. The pathways and growth processes that produce biological materials can influence the mechanical properties of the materials, which can in turn shape the higher level function of the system into which the materials are incorporated. Characterizing a biological system requires thorough knowledge of the underlying materials, including their mechanical function, diversity, evolution, and sensitivity to the environment. Anthropogenic activity is driving rapid and widespread changes to the natural environment and global climate, which are influencing organismal growth and physiology in myriad ways. Here, we briefly introduce a collection of articles that focus on the intersection of anthropogenic activity and the mechanical function of biological materials, as part of the “Global Change in a Material World” bundle for Integrative and Comparative Biology. In addition, we provide an analysis of the current scientific literature in this field, highlighting an urgent need to better understand how changes to our world, driven by human activity, are influencing the fundamental architecture and mechanical performance of organisms across the globe.

Abstract Biogenic coalbed methane (CBM) is a developing clean energy source. However, it is unclear how the mechanisms of bio-methane production with different sizes of coal. In this work, pulverized coal (PC) and lump coal (LC) were used for methane production by mixed fungi-methanogen microflora. The lower methane production from LC was observed. The aromatic carbon of coal was degraded slightly by 2.17% in LC, while 11.28% in PC. It is attributed to the proportion of lignin-degrading fungi, especially Penicillium, which was reached 67.57% in PC on the 7th day, higher than that of 11.38% in LC. The results suggested that the limited interaction area in LC led to microorganisms hardly utilize aromatics. It also led the accumulation of aromatic organics in the fermentation broth in PC. Increasing the reaction area of coal and facilitating the conversion of aromatic carbon are suggested means to increase methane production in situ.

AbstractWe report a nickel complex for catalytic oxidation of ammonia to dinitrogen under ambient conditions. Using the aryloxyl radical 2,4,6‐tri‐tert‐butylphenoxyl (tBu3ArO⋅) as a H atom acceptor to cleave the N−H bond of a coordinated NH3 ligand up to 56 equiv of N2 per Ni center can be generated. Employing the N‐oxyl radical 2,2,6,6‐(tetramethylpiperidin‐1‐yl)oxyl (TEMPO⋅) as the H‐atom acceptor, up to 15 equiv of N2 per Ni center are formed. A bridging Ni‐hydrazine product identified by isotopic nitrogen (15N) studies and supported by computational models indicates the N−N bond forming step occurs by bimetallic homocoupling of two paramagnetic [Ni]−NH2 fragments. Ni‐mediated hydrazine disproportionation to N2 and NH3 completes the catalytic cycle.

This research provides new techno-economic insights into integrating flexible combined-cycle gas turbines with post-combustion carbon capture and storage (CCGT-CCS) for low-carbon power systems. This study developed a versatile unit-commitment optimisation model of CCGT-CCS. This research highlights the model’s adaptability, accommodating diverse techno-economic configurations, feed gases (e.g., biomethane or fossil natural gas), carbon capture rates, and policy instruments. This generalisation empowers seamless application in various policy and market contexts, making the model a potent tool for researchers and policymakers. While the case study focuses on the UK, the findings are relevant for most low-carbon power systems with variable renewable supplies. Analysing the UK’s net-zero scenarios from 2030 to 2050, the economic viability of flexible CCGT-CCS was highlighted. Intertemporal flexibility proves highly valuable with greater electricity price volatility, with a total ROI range of 81–246 %, surpassing the CCGT-CCS plant’s ROI (7–64 %). A flexible solvent storage solution should be seen in the context of the overall system ‘flexibility’ requirements of a low-carbon power system. On a cost basis, solvent storage represents just a fraction of the capital costs of more “mainstream” energy storage technologies, such as lithium-ion batteries or hydro-pumped storage, while CCGT-CCS offers firm power. Overall, while seen as a rather technical solution, if abated fossil fuel generation is to be part of a future low-carbon power system, having this flexibility adds economic benefits not just to operators but also improves overall system security and complements high shares of variable renewables on the grid.

Synopsis Marine organisms have complex life histories. For broadcast spawners, successful continuation of the population requires their small gametes to make contact in the water column for sufficiently long periods for fertilization to occur. Anthropogenic climate change has been shown to impact fertilization success in various marine invertebrates, including sea urchins, which are key grazers in their habitats. Gamete performance of both sexes declined when exposed to elevated temperatures and/or pCO2 levels. Examples of reduced performance included slower sperm swimming speed and thinning egg jelly coat. However, such responses to climate change stress were not uniform between individuals. Such variations could serve as the basis for selection. Fertilization kinetics have long been modeled as a particle collision process. Here, we present a modified fertilization kinetics model that incorporates individual variations in performance in a more environmentally relevant regime, and which the performance of groups with different traits can be separately tracked in a mixture. Numerical simulations highlight that fertilization outcomes are influenced by changes in gamete traits as they age in sea water and the presence of competition groups (multiple dams or sires). These results highlight the importance of considering multiple individuals and at multiple time points during in vivo assays. We also applied our model to show that interspecific variation in climate stress vulnerabilities elevates the risk of hybridization. By making a numerical model open-source, we aim to help us better understand the fate of organisms in the face of climate change by enabling the community to consider the mean and variance of the response to capture adaptive potential.

Synopsis A central question in ecology is to what extent do trophic interactions govern the structure and function of communities? This question is becoming more pressing as trophic interactions shift with rapid climate change. Sea urchins and abalone are key invertebrates in the habitats where they reside. Sea urchins are critical members of exemplar trophic cascades in kelp forests due to their impact on kelp establishment and maintenance; yet their populations are controlled by predators, such as sea otters and sunflower sea stars. Abalone compete with urchins for macroalgal food resources and therefore can help regulate urchin populations in kelp forests. Given that both urchin tests and abalone shells used for predator defense are comprised of calcium carbonate, much research has been conducted on the impacts of ocean acidification (OA) on these calcified structures. A growing body of literature has shown that urchin tests are less calcified and break with less force under OA conditions. Less is known about abalone, but their shells also appear to respond negatively to OA. Using kelp forest communities as exemplar ecosystems, we discuss the morphological, biomechanical, and physiological responses to OA in urchins and abalone and consider how these individual level responses scale to trophic interactions and ultimately whole ecosystem processes. Although the impacts of OA on the calcified structures used for defense have been well studied, calcified mechanisms for food consumption, such as the Aristotle's lantern of urchins, are much less understood. Thus, examining both the feeding and defense sides of trophic interactions would greatly improve our understanding of OA responses across individual to ecosystem scales. More generally, measurements of morphological, biomechanical, and physiological responses to OA can be made in individuals to help predict higher level ecological responses, which would greatly contribute to broader predictions of whole ecosystem responses to OA.

Synopsis Cities, through the generation of urban heat islands, provide a venue for exploring contemporary convergent evolution to climatic warming. We quantified how repeatable the evolution of heat tolerance, cold tolerance, and body size was among diverse lineages in response to urban heat islands. Our study revealed significant shifts toward higher heat tolerance and diminished cold tolerance among urban populations. We further found that the magnitude of trait divergence was significantly and positively associated with the magnitude of the urban heat island, suggesting that temperature played a major role in the observed divergence in thermal tolerance. Despite these trends, the magnitude of trait responses lagged behind environmental warming. Heat tolerance responses exhibited a deficit of 0.84°C for every 1°C increase in warming, suggesting limits on adaptive evolution and consequent adaptational lags. Other moderators were predictive of greater divergence in heat tolerance, including lower baseline tolerance and greater divergence in body size. Although terrestrial species did not exhibit systematic shifts toward larger or smaller body size, aquatic species exhibited significant shifts toward smaller body size in urban habitats. Our study demonstrates how cities can be used to address long-standing questions in evolutionary biology regarding the repeatability of evolution. Importantly, this work also shows how cities can be used as forecasting tools by quantifying adaptational lags and by developing trait-based associations with responses to contemporary warming.