Alpha functions are of critical importance to the cubic equations of state (EOSs) while most existing alpha functions are correlations in the empirical/semi-empirical formulations and limited to the bulk phase calculations. In this study, a new analytical alpha function and its nanoscale-extended formulation, which considers the strong intermolecular interactions under confinement effects, are developed based on the virial EOS and statistical thermodynamics. The proposed alpha functions, coupled with a nanoscale-extended EOS, are validated for a general use and be accurate to calculate the phase and thermodynamic properties of a wide variety of components in bulk phase and nanopores.
Increasing attention has been paid to anaerobic ammonium oxidation (anammox) in river ecosystems due to their special role in the global nitrogen cycle from land to the ocean. This study have revealed the spatial patterns of anammox bacterial response to geographic characteristics and dam operation along the Yangtze River, using N-15 tracers and molecular analyses of microbial communities in sediment samples over a 4300 km continuum. Here we found a significant temperature-related increase in anammox bacterial abundance and alpha diversity from mountainous area in the upper, fluvial plain area in the middle and lower reach, to the river mouth. In contrast, an opposite trend in anammox contribution to N-2 production (ra) was observed down the Yangtze River due to enhanced denitrification induced by spatial heterogeneity of total organic carbon. Interestingly, the Three Gorges Dam resulted in an intensive erosion and thus a change from muddy to sandy sediments within 400 km downstream the dam, which readjusted the anammox community characterized with a decreased bacterial diversity and enhanced anammox contribution to nitrogen loss. Our study highlights the importance of natural and anthropogenic impacts on anammox bacterial community and function in a complex large river ecosystem. (c) 2019 Published by Elsevier B.V.
ABSTRACT Argumentation, the act of defending one's inherent knowledge or views through speech expression, is a kind of widespread information expression and communication behavior. In this poster, we aim to explore the characteristics and patterns of argumentation in social media to examine basic rules the patterns follow by conducting content analysis of the transcript of a WeChat Group Chat. We build a theoretical model of argumentation behavior in mobile social media using the inductive coding and find that social media has a great influence on argumentation.
The airborne occurrence, isomer profiles, and phase distribution of perfluoroalkyl acids (PFAAs), including perfluoroalkyl carboxylates (PFCAs) and sulfonates (PFSAs), have received little scientific attention to date. Here we collected gaseous and particulate phase (PM2.5) samples in China, between June and November 2013, using alkalized annular denuders and downstream filters toavoid sampling artefacts associated with traditional air sampling. We analysed the concentrations of 18 linear PFAAs and the branched isomers of perfluorooctanoate (PFOA) and perfluorooctane sulfonate (PFOS). Concentra- tions of total PFAAs were dominated by PFCAs, with a range of 6.6e610 pg/m3 in the gaseous phase and 2.3e290 pg/m3 in the particulate phase. Concentrations of total PFCAs were higher in summer than winter in both phases. Branched PFOA isomers accounted for 10e22% of total PFOA in the gaseous phase and 13e24% in the particulate phase, which is close to, but slightly lower than, their abundance in the commercial PFOA mixtures manufactured using the electrochemical fluorination (ECF) process. In con- tract, branched PFOS isomers accounted for 26-63% of total PFOS in the gaseous phase and 39-77% in the particulate phase, which is much higher than their abundance in commercial PFOS mixtures manufac- tured by ECF. Most PFCAs had mean particle-associated fractions (F) higher than 0.5. PFHxS had a much higher mean F (0.65) than linear PFOS (0.31). We hypothesise that PFAAs observed in Beijing air may originate from the local water bodies through processes such as aerosol generation, although trans- formation of precursors also contribute.
We derive the definition of the Berry phase for adiabatic transport of a composite Fermion (CF) in a half-filled composite Fermi-liquid (CFL). It is found to be different from that adopted in previous investigations by Geraedts et al. With the definition, the numerical evaluation of the Berry phase becomes robust and free of extraneous phase factors. We show that the two forms of microscopic wave-functions of the CFL, i.e., the Jain-Kamilla type wave function and the standard CF wave function, yield different distributions of the Berry curvature in the momentum space. For the former, the Berry curvature has a continuous distribution inside the Fermi sea and vanishes outside, whereas for the latter, the Berry curvature is uniform in the whole momentum space. To facilitate an analytic derivation for the latter, we reveal a simple structure of standard CF wave functions by establishing their connections to the Segal-Bargmann transform. We conclude that the CF with respect to both the microscopic wave-functions is not a massless Dirac particle.
Abstract Identifying hotspots of species richness/rarity is the most commonly used approach worldwide for defining areas of high conservation importance. However, the use of the hotspot method limits one's ability to protect or exclude particular species as all species are treated equally. Particularly, range-restricted species require high conservation attention because they are more vulnerable than common species. However, the efficiency of the hotspot method in capturing range-restricted species is yet to be explored, although it is known that this method provides low species coverage. Here, using a comprehensive database of Chinese woody plants, we mapped the diversity pattern of 11,405 species at the spatial resolution of 50 × 50 km2 and identified hotspot areas using 1, 2.5, 5, 10, 25, and 50% thresholds. We then evaluated the proportion of range-restricted versus common species captured/missed by each hotspot threshold. We found that the commonly used hotspot thresholds (5 and 10%) failed to capture 41–45% of range-restricted species, which indicates that using the hotspot method for conservation prioritization exposes range-restricted species to high extinction risk. Relying entirely on the hotspot method to prioritize conservation areas, therefore, can be risky not only because it provides low species coverage but also because the missed species are mostly range-restricted species. We advocate adopting more efficient methods, such as systematic conservation planning, rather than the hotspot method, to increase the coverage of range-restricted species in designated priority areas and balance the needs of biodiversity conservation and economic development.