Fingerprinting sulfur speciation in aprotic electrolytes is a key to understand fundamental chemistry and design well-performing lithium–sulfur(Li–S)batteries.Lithium polysulfide(LiPS)dissolution and deposition in ether-based electrolytes during redox reactions have been probed and established by spectroscopy and microscopy.However,detailed LiPS structure and solvation properties influenced by conventional and newly developed electrolytes remain elusive,which exert fundamental challenges and practical difficulties in decoupling battery performance from electrolyte volume.This perspective aims to provide timely information to uncover underlying mechanisms that rein in sulfur speciation by considering the charge density of LiPSs and the coordination strength of solvents/salts.The discussion starts with unlocking the baseline electrolyte formulation to investigate its role in LiPS formation and compatibility.After that,the term coordination strength is used instead of donor number and dielectric constant to describe interactions between solvents and LiPSs and to reveal LiPS structure evolution.This work is expected to encourage the discovery of new electrolyte working mechanisms to develop energy-dense and power-intensive Li–S batteries.
Atmospheric iron has crucial effects on biogeochemical cycles,atmospheric processing,global climate,and human health.In this study,atmospheric dustfall samples were collected from six functional areas in Xi'an,China,from 2020 to 2021.The spatiotemporal distributions and deposition fluxes of total and water-soluble(ws)Fe as well as the speciation and potential sources of ws-Fe were characterized.Industrial areas had the highest concentrations of total Fe and ws-Fe,which were mainly due to copious emissions of heavy metals during manufacturing.The total Fe concentrations peaked in spring,primarily due to the substantial input of crustal dust,which also led to the lowest Fe solubility in this season.By contrast,the highest levels of ws-Fe occurred during winter due to an increase in biomass combustion.Among the water-soluble forms,ws-Fe(II)was dominant and accounted for 74.8%of the total amount of ws-Fe.Crustal dust was the main contributor to total Fe,whereas biomass burning primarily contributed to peak ws-Fe concentrations.The average total and ws-Fe deposition fluxes in Xi'an were the highest in spring and lowest in autumn,which were related to the distributions of the dustfall deposition fluxes and their Fe contents during these periods.Our study provided a broader and comprehensive understanding of atmospheric iron deposition in Chinese urban area,which is of positive significance for understanding atmospheric chemistry and global climate change.
Species is a fundamental concept in evolutionary biology and biodiversity.However,existing species definitions are often influenced by artificial factors or are challenging in practical application,leading to confusion in species classification.Due to uncertain environmental changes and random genetic drift,the fitness expectations of a population may shift,causing species to evolve to a new evolutionary state based on their current instantaneous fitness within a dynamic fitness landscape.This contrasts with the classic static fitness landscape,where fitness expectations are constant.In a dynamic fitness landscape,speciation may exhibit path dependence,where the evolution of traits follows a probabilistic path,creating feedback that shapes evolutionary trajectories.The path-dependent evolutionary mechanism suggests that species survival within an ecosystem is not directly determined by their fitness but by the probability of their evolutionary pathways.This model also indicates that species can coexist with varying probabilities under limited environmental pressures.Consequently,new species,cryptic species,or sympatric species may emerge via path-dependent evolutionary processes.Within this framework,we developed a mathematical species concept,which may guide future species classification methodologies.
Hybridization and polyploidization have made great contributions to speciation,heterosis,and agricultural production within plants,but there is still limited understanding and utilization in animals.Subgenome structure and expression reorganization and cooperation post hybridization and polyploidization are essential for speciation and allopolyploid success.However,the mechanisms have not yet been comprehensively assessed in animals.Here,we produced a high-fidelity reference genome sequence for common carp,a typical allotetraploid fish species cultured worldwide.This genome enabled in-depth analysis of the evolution of subgenome architecture and expression responses.Most genes were expressed with subgenome biases,with a trend of transition from the expression of subgenome A during the early stages to that of subgenome B during the late stages of embryonic development.While subgenome A evolved more rapidly,subgenome B contributed to a greater level of expression during development and under stressful conditions.Stable dominant patterns for homoeologous gene pairs both during development and under thermal stress suggest a potential fixed heterosis in the allotetraploid genome.Preferentially expressing either copy of a homoeologous gene at higher levels to confer development and response to stress indicates the dominant effect of heterosis.The plasticity of subgenomes and their shifting of dominant expression during early development,and in response to stressful conditions,provide novel insights into the molecular basis of the successful speciation,evolution,and heterosis of the allotetraploid common carp.
