The influence of the zeolite framework type (FAU, CHA, MOR, MFI) and the crystallographic position on the acidity of zeolites is investigated. The most stable Brønsted acid sites of the high-silica frameworks are considered: O1-H (FAU), O1-H (CHA), Al4-O2(H)-Si (MOR), and Al7-O17(H)-Si4 (MFI, sinusoidal channel). The latter is compared with the less stable Al12-O24(H)-Si12 position (MFI, channel intersection). Both the heat of the deprotonation and the heat of ammonia adsorption are considered as measures of acid strength. A novel hybrid computational scheme is used that combines the quantum mechanical cluster description (QM) of the active site with interatomic potentials (Pot) for the periodic zeolite framework. Specifically, the Hartree-Fock method (QM) is combined with ab initio shell model potentials (Pot) for the zeolite framework and its interaction with ammonia and ammonium ions. Complete relaxation of the framework is possible within this scheme and long-range corrections to the reaction energies are obtained from the shell model potentials. The total QM-Pot reaction energies are remarkably stable with increasing cluster size. The calculated heats of deprotonation suggest the acidity sequence Y (1171 kJ/mol) > CHA (1190 kJ/mol) > MOR (1195 kJ/mol) > ZSM-5 (1200 kJ/mol), which is neither explained by local structure effects nor by crystal potential effects alone. The calculated heats of NH 3 adsorption suggest the sequence MOR > CHA ≈ Y > ZSM-5. The different order is caused by specific interactions of NH 4 + with the negatively charged catalyst surface. The predicted heats of NH 3 adsorption are -119, -114, -113, and -109 kJ/mol, respectively. Comparison is made with microcalorimetry and TPD data.

Dispersal, the behaviour ensuring gene flow, tends to covary with a number of morphological, ecological and behavioural traits. While species-specific dispersal behaviours are the product of each species' unique evolutionary history, there may be distinct interspecific patterns of covariation between dispersal and other traits ('dispersal syndromes') due to their shared evolutionary history or shared environments. Using dispersal, phylogeny and trait data for 15 terrestrial and semi-terrestrial animal Orders (> 700 species), we tested for the existence and consistency of dispersal syndromes across species. At this taxonomic scale, dispersal increased linearly with body size in omnivores, but decreased above a critical length in herbivores and carnivores. Species life history and ecology significantly influenced patterns of covariation, with higher phylogenetic signal of dispersal in aerial dispersers compared with ground dwellers and stronger evidence for dispersal syndromes in aerial dispersers and ectotherms, compared with ground dwellers and endotherms. Our results highlight the complex role of dispersal in the evolution of species life-history strategies: good dispersal ability was consistently associated with high fecundity and survival, and in aerial dispersers it was associated with early maturation. We discuss the consequences of these findings for species evolution and range shifts in response to future climate change.

The approach used describes the Brønsted site by the Hartree−Fock method and a T(O)DZP basis set, while the periodic zeolite framework and the interaction between the active site and the framework are described by a shell model potential parametrized on the same type of ab initio data for cluster models. It is capable of reproducing the effect of the crystallographic position and of different framework structures on the properties and reactivity of zeolitic Brønsted sites. For H-faujasite (Si/Al = 47) protonation of all four crystallographically different oxygen positons is considered. In agreement with experiment protonation on O(1) and O(3) is preferred. For the orthorhombic form of H-ZSM-5 (Si/Al = 95) protonation of the Al(7)−O(17)H−Si(4) site proves more stable than protonation at the Al(12)−O(24)−Si(12) site located at the channel intersection. In agreement with experiments, the OH vibrational frequency is predicted to decrease according to O(1)H-FAU > H-ZSM-5 > O(3)H-FAU, and the 1H NMR chemical shift to increase in the same sequence. The method also yields absolute and site specific acidity values. The deprotonation energya measure of acidityobtained by this combined scheme is decomposed into the quantum mechanical contribution for the cluster itself and the long-range contribution. The former reflects the structural constraints imposed on the active site by the framework and the latter the influence of the crystal potential. With increasing cluster size the long-range correction decreases slowly, while the total energy stays remarkably stable within a few kJ/mol. For H-ZSM-5 and H-faujasite heats of deprotonation (proton affinities) of 1205 and 1169 kJ/mol, respectively, are calculated. Hence, for the same large Si/Al ratio Brønsted sites in the faujasite lattice are predicted to be more acidic than in the ZSM-5 lattice. This difference is due to differences of both the local structures (including the structure relaxation) and the crystal potentials. No correlation is found between T−O−T bond angles or 1H NMR chemical shifts and heats of deprotonation.

Associations between biological traits of animals and climate are well documented by physiological and local-scale studies. However, whether an ecophysiological phenomenon can affect large-scale biogeographical patterns of insects is largely unknown. Insects absorb energy from the sun to become mobile, and their colouration varies depending on the prevailing climate where they live. Here we show, using data of 473 European butterfly and dragonfly species, that dark-coloured insect species are favoured in cooler climates and light-coloured species in warmer climates. By comparing distribution maps of dragonflies from 1988 and 2006, we provide support for a mechanistic link between climate, functional traits and species that affects geographical distributions even at continental scales. Our results constitute a foundation for better forecasting the effect of climate change on many insect groups.

Summary1. Data on the species richness of phytophagous insects and mites associated with 25 tree genera occurring as natives in Germany were compiled and compared to data for British trees published by Kennedy & Southwood (1984). For tree genera occurring in Germany and Britain patterns of species richness and composition of phytophage faunas were similar. 2. Present abundance of trees, their distributional history during the Holocene, morphological traits and taxonomic isolation were used to explain the variance of species richness and proportion of specialists across tree genera occurring as natives in Germany. Tree genera were either used as independent data points or to calculate phylogenetically independent contrasts. For the latter approach, a phylogeny for the tree genera was generated from published rbc L gene sequences. In general, the conclusions from the two types of analyses were similar. 3. The species richness of phytophages on German tree genera were positively related to present tree abundance, tree height and tree abundance derived from pollen samples. For phylogenetically independent contrasts the length of time a genus was present since the end of the last glaciation also became significant. 4. The proportions of specialists showed a negative relationship with present abundance of trees, a positive relationship with taxonomic isolation as well as the length of time of genus was present since the end of the last glaciation. For phylogenetically independent contrasts only the latter two variables remained significant. 6. Overall the results support the species-area and the coevolutionary hypotheses.