A quantitative structure−property relationship (QSPR) treatment of the normal boiling points was performed for a structurally wide variety of organic compounds using the CODESSA (comprehensive descriptors for structural and statistical analysis) technique. A highly significant two-parameter correlation (R 2 = 0.9544, s = 16.2 K) employs just two molecular parameters, a bulk cohesiveness descriptor, G I 1/3, and the area-weighted surface charge of the hydrogen-bonding donor atom(s) in the molecule. A more refined QSPR model (with R 2 = 0.9732 and s = 12.4 K) includes, in addition, the most negative atomic partial charge and the number of the chlorine atoms in the molecule. The four-parameter equation offers an average predicted error of 2.3% for a standard set of compounds with an average experimental error of 2.1%. The QSPR equations developed allow remarkably accurate predictions of the normal boiling points for a number of simple inorganic compounds, including water.

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QSPR correlation equations were developed for the prediction of the solubilities of organic gases and vapors in water. A two-parameter correlation with the squared correlation coefficient R 2 ) 0.977 gives excellent predictions for 95 alkanes, cycloalkanes, alkenes, alkylarenes, and alkynes. A satisfactory description (R 2 ) 0.941) of the gas solubilities of 406 organic compounds with a large structural variablity was obtained using a five-parameter QSPR equation. Notably, all the parameters involved in these equations can be derived solely from the chemical structure of the compounds which makes them very useful for the prediction of the solubilities of unknown or unavailable compounds.

Biodiversity is thought to help regulate the impacts of disease through the dilution effect, where biodiversity among potential host species helps limit the impacts of pathogens. However, our knowledge is fragmentary about the direction and magnitude of the effects of plant species richness on disease impact. Here, we gathered data from 145 comparisons presented in 21 papers to conduct a systematic meta‐analysis on the effect of plant species richness on aboveground plant disease impact. We estimated the effect size using Pearson's correlation coefficient (r) with Fisher's z‐transformation. We evaluated how the magnitude of effect size varies between systems, including ecosystem type (grassland versus forest), pathogen taxon (virus versus fungus), study design (observational versus manipulative), parasite life history (biotroph versus necrotroph) and kinds of symptoms associated with the disease. We also tested whether there was a latitudinal trend of the effect size. We found there was a significant overall dilution effect in plant communities, but the magnitude varied among systems. Studies based on manipulative experiments and those in grassland ecosystems showed a significant dilution effect, as did both viral and fungal pathogens. Furthermore, obligate biotrophic pathogens but not necrotrophs showed a significant dilution effect. Diseases with different kinds of symptom manifestation differed, but not in a consistent pattern to the life history of the pathogens. The dilution effect was notably stronger at lower latitudes in the mid‐temperate region than at higher latitudes. This latitudinal trend existed in forest ecosystems, both observational and manipulative experiments, and necrotrophs. Dilution effects occur prevalently in plant communities, although the magnitude depends on ecosystem type, pathogen life history and kinds of symptoms associated with the disease. In conclusion, this study shows the importance of preserving the biodiversity of plants for maintaining ecosystem health.

Invasive alien plants are likely to be released from specialist herbivores and at the same time encounter biotic resistance from resident generalist herbivores in their new ranges. The Shifting Defense hypothesis predicts that this will result in evolution of decreased defense against specialist herbivores and increased defense against generalist herbivores. To test this, we performed a comprehensive meta-analysis of 61 common garden studies that provide data on resistance and/or tolerance for both introduced and native populations of 32 invasive plant species. We demonstrate that introduced populations, relative to native populations, decreased their resistance against specialists, and increased their resistance against generalists. These differences were significant when resistance was measured in terms of damage caused by the herbivore, but not in terms of performance of the herbivore. Furthermore, we found the first evidence that the magnitude of resistance differences between introduced and native populations depended significantly on herbivore origin (i.e., whether the test herbivore was collected from the native or non-native range of the invasive plant). Finally, tolerance to generalists was found to be higher in introduced populations, while neither tolerance to specialists nor that to simulated herbivory differed between introduced and native plant populations. We conclude that enemy release from specialist herbivores and biotic resistance from generalist herbivores have contrasting effects on resistance evolution in invasive plants. Our results thus provide strong support for the Shifting Defense hypothesis.

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Solar-driven catalytic oxidation of 5-hydroxymethylfurfural (HMF) into 2,5-diformylfuran (DFF) coupled with H2 evolution has been considered a promising approach. The exploration of an active and stable photocatalyst still remains challenging work. Herein, we found that the flexible ultrathin graphitic carbon nitride (UCNT) could be an ideal candidate. The UCNT exhibits photocatalytic performance in selective oxidation of HMF into DFF coupled with H2 evolution with activities of 95.0 and 92.0 μmol g–1 h–1 under visible light irradiation. Importantly, the UCNT also demonstrates high DFF selectivity (95%) and good cycling stability. The activity may be ascribed to the strong specific interaction between HMF and UCNT. Solid-state nuclear magnetic resonance (NMR) and density functional theory (DFT) results reveal that the twisted structure of HMF molecules could form a strong interaction between HMF and UCNT, reducing the dehydrogenation energy barrier for HMF oxidation. In addition, mechanistic studies reveal that •C6H4O3 is the key radical intermediate during the HMF oxidation process by a in situ electron spin resonance (ESR) trapping test. Our work clarifies the interaction of complex biomass molecules on the flexible catalyst surface and provides views on the further development of heterogeneous catalytic biomass conversion.