Search results for "fossil"
showing 10 items of 412 documents
LCA of a solar heating and cooling system equipped with a small water–ammonia absorption chiller
2012
The development of renewable energy technologies is a critical tool for reducing climate change and the reliance on fossil fuels. However, renewable energy technologies cannot be considered totally clean because they require energy consumption and have environmental impacts that cannot be neglected during their life cycle. In this paper, the life cycle assessment methodology was applied to assess resource use and other environmental burdens related to the entire life-cycle steps of a solar cooling plant. The investigated system works with an absorption chiller assisted by a solar plant. Two back-up configurations (hot back-up and cold back-up) were examined in two localities: Palermo (south…
Introduction of Offshore Wave, Wind and Solar Energies in Vietnam
2020
In Vietnam, the energy demand shows an ever-increasing trend. To limit the utilization of fossil fuels and the following consequences for the environment, renewable energy sources must be adopted. In this context, the paper assesses the utilization of offshore wind and sea wave, by considering a commercial wind turbine and a prototypical wave energy converter. Solar energy can be optionally also collected by this device. An algorithm is introduced to find the best composition of the three sources able to cover a desired share of energy demand. The approach is applied to Ca Mau, a province in the southern part of Vietnam. Finally, the results encourage the adoption of these energy sources th…
Formation of high added value chemicals by photocatalytic treatment of biomass
2020
The depletion of fossil fuel requires the search for alternative renewable feedstock and environmentally friendly methods for the production of high value-added compounds and fuels. In this context, the efficient use of biomass has emerged as a significant research field as it represents an alternative green and renewable carbon source. Various technologies have been explored for this purpose and heterogeneous photocatalysis represents a valid alternative to the catalytic methods since it can be carried out under mild experimental conditions without the addition of harmful oxidizing agents. Different biomass components have been used as the starting materials, and many valuable chemicals h…
Sexual dimorphism in primates: Where are we and where do we go from here?
1986
There are currently several debates taking place in palaeoanthropological circles in which the issue of sexual dimorphism is crucial. During the 60th Jubilee of the discovery of the TaungAustralopithecus skull, the authors concurred that much of the debate was due to differences in perception concerning dimorphism, and it was suggested that a study session dealing principally with sexual dimorphism in Primates should be organised with a view to determining what, if anything, could be observed in extant primates that might be utilised for determining the existence of dimorphism in fossil species. An advertisement was placed in the Journal of Human Evolution, calling for papers. Response was …
On the hidden significance of differing micro-sites on tree-ring based climate reconstructions
2015
Tree-ring chronologies are commonly extended back in time by combining samples from living trees with relict material preserved in man-made structures or natural archives (e.g. lakes). Although spatially close, these natural archives and living-tree-sites often comprise different micro-climates. Inhomogeneous growth conditions among these habitats, which may yield offsets in growth-rates, require caution in data processing. Here we assess species-specific growth dynamics in two micro-habitats and their potential effects on long chronologies by combining tree-ring data from different living-tree-sites with an âartificialâ subfossil dataset. Well replicated (nâ>â80) Norway spruce (…
Ventastega curonica and the origin of tetrapod morphology.
2008
The gap in our understanding of the evolutionary transition from fish to tetrapod is beginning to close thanks to the discovery of new intermediate forms such as Tiktaalik roseae. Here we narrow it further by presenting the skull, exceptionally preserved braincase, shoulder girdle and partial pelvis of Ventastega curonica from the Late Devonian of Latvia, a transitional intermediate form between the 'elpistostegids' Panderichthys and Tiktaalik and the Devonian tetrapods (limbed vertebrates) Acanthostega and Ichthyostega. Ventastega is the most primitive Devonian tetrapod represented by extensive remains, and casts light on a part of the phylogeny otherwise only represented by fragmentary ta…
An assessment of energy vulnerability in Small Island Developing States
2020
Abstract Small Island Developing States (SIDS) suffer from several structural characteristics that jeopardize their ability to achieve a sustainable energy future. Their reliance on imported fossil fuels exacerbates their exposure to external threats on international energy markets. Their energy systems are also exposed to internal disturbances that disrupt the proper production, transmission and distribution of energy. The aim of this paper is to investigate the extent to which island energy systems are vulnerable to shocks and internal dysfunctions over which they have no control. For this purpose, we build a composite index of energy vulnerability using the Multi-Layer Benefit-of-the-Dou…
Syphilis 2001 a palaeopathological reappraisal
2002
The origin and subsequent spread of the treponematoses, especially that of venereal syphilis, has been the subject of considerable scientific attention. Various theories were put forth and palaeopathological specimens were used for their validation in recent times. One influential contribution was the paper by Baker & Armelagos in 1988. Numerous new findings and results on both sides of the Atlantic call for a new evaluation of the available osseous material. A review of the recent literature leads to the suggestion of a worldwide distribution of non-venereal treponemal disease since the emergence of Homo and to a first epidemic outbreak of venereal syphilis in Europe of the late 15th and t…
Optimization and Multicriteria Evaluation of District Heat Production and Storage
2019
Climate change mitigation policy requires reducing dependence on fossil fuels and transition to low carbon energy production in district heating (DH). We study here inclusion of two kinds of renewable energy to a CHP based DH system in Finland: solar heat and ground source heat. In addition, we apply heat storages to balance the gap between production and fluctuating demand. The optimal operation of the extended systems is determined by a simulation and optimization model to minimize the operating costs. We evaluate the different possible extensions in terms of multiple economic, technical and environmental criteria using Stochastic Multicriteria Acceptability Analysis (SMAA). The results s…
First record of Anisian deposits in the Betic External Zone of southern Spain and its paleogeographical implications
2023
In the External Zones of the Betic Cordillera (S Spain), upper Muschelkalk (Ladinian) facies have been known for decades; however, so far there is no stratigraphic record of Anisian deposits. In the present study, new biostratigraphic data from a carbonate succession in the easternmost Subbetic domain reveal a Pelsonian-Illyrian (Anisian) age. The nautiloids Germanonautilus salinarius and Germanonautilus saharonicus are documented for the first time in the Iberian Peninsula, and together with the brachiopod Tetractinella trigonella and the bivalves Neoschizodus orbicularis and Myophoria vulgaris they represent marker fossils of Anisian deposits previously described from many other basins, b…