21 research outputs found
Ternary thiophene\u2013X\u2013thiophene semiconductor building blocks (X = fluorene, carbazole, phenothiazine): Modulating electronic properties and electropolymerization ability by tuning the X core
To achieve rationalization criteria for target-oriented molecular design of Th\u2013X\u2013Th (Th = thiophene)
semiconductor building blocks, we have carried out an extensive investigation on the effects of the X
core (X = fluorene, carbazole or phenothiazine) on the electronic properties and polymerization ability
of Th\u2013X\u2013Th monomers and on the electronic and structural properties of the corresponding periodic
conducting polymers \u2013(Th\u2013X\u2013Th)n\u2013, obtained by electropolymerization and, for comparison\u2019s sake, by
FeCl3-catalyzed polymerization and/or Suzuki coupling. The effects of molecule bending and of solubilising
bulky alkyl substituents have also been considered. The systematic, exhaustive template sequence
combined with a rigorous, multitechnique investigation protocol affords a unique data library and a
complete set of reliable interpretative/predictive guidelines
Notulae to the Italian native vascular flora: 8
In this contribution, new data concerning the distribution of native vascular flora in Italy are presented. It includes new records, confirmations, exclusions, and status changes to the Italian administrative regions for taxa in the genera Ajuga, Chamaemelum, Clematis, Convolvulus, Cytisus, Deschampsia, Eleocharis, Epi- pactis, Euphorbia, Groenlandia, Hedera, Hieracium, Hydrocharis, Jacobaea, Juncus, Klasea, Lagurus, Leersia, Linum, Nerium, Onopordum, Persicaria, Phlomis, Polypogon, Potamogeton, Securigera, Sedum, Soleirolia, Stachys, Umbilicus, Valerianella, and Vinca. Nomenclatural and distribution updates, published elsewhere, and corrigenda are provided as Suppl. material
Notulae to the Italian native vascular flora: 8.
In this contribution, new data concerning the distribution of native vascular flora in Italy are presented.
It includes new records, confirmations, exclusions, and status changes to the Italian administrative regions
for taxa in the genera Ajuga, Chamaemelum, Clematis, Convolvulus, Cytisus, Deschampsia, Eleocharis, Epipactis,
Euphorbia, Groenlandia, Hedera, Hieracium, Hydrocharis, Jacobaea, Juncus, Klasea, Lagurus, Leersia,
Linum, Nerium, Onopordum, Persicaria, Phlomis, Polypogon, Potamogeton, Securigera, Sedum, Soleirolia,
Stachys, Umbilicus, Valerianella, and Vinca. Nomenclatural and distribution updates, published elsewhere,
and corrigenda are provided as Suppl. material 1
Lake sediment fecal and biomass burning biomarkers provide direct evidence for prehistoric human-lit fires in New Zealand
Deforestation associated with the initial settlement of New Zealand is a dramatic example of how humans can alter landscapes through fire. However, evidence linking early human presence and land-cover change is inferential in most continental sites. We employed a multi-proxy approach to reconstruct anthropogenic land use in New Zealand’s South Island over the last millennium using fecal and plant sterols as indicators of human activity and monosaccharide anhydrides, polycyclic aromatic hydrocarbons, charcoal and pollen as tracers of fire and vegetation change in lake-sediment cores. Our data provide a direct record of local human presence in Lake Kirkpatrick and Lake Diamond watersheds at the time of deforestation and a new and stronger case of human agency linked with forest clearance. The first detection of human presence matches charcoal and biomarker evidence for initial burning at c. AD 1350. Sterols decreased shortly after to values suggesting the sporadic presence of people and then rose to unprecedented levels after the European settlement. Our results confirm that initial human arrival in New Zealand was associated with brief and intense burning activities. Testing our approach in a context of well-established fire history provides a new tool for understanding cause-effect relationships in more complex continental reconstructions